This commit introduces basic netlink support with family registration/unregistration functionalities and stub pre/post-doit.

More importantly it introduces the YAML uAPI description along with its auto-generated files: - include/uapi/linux/ovpn.h - drivers/net/ovpn/netlink-gen.c - drivers/net/ovpn/netlink-gen.h

Cc: donald.hunter@gmail.com Signed-off-by: Antonio Quartulli antonio@openvpn.net --- Documentation/netlink/specs/ovpn.yaml | 372 ++++++++++++++++++++++++++++++++++ MAINTAINERS | 2 + drivers/net/ovpn/Makefile | 2 + drivers/net/ovpn/main.c | 17 +- drivers/net/ovpn/main.h | 14 ++ drivers/net/ovpn/netlink-gen.c | 213 +++++++++++++++++++ drivers/net/ovpn/netlink-gen.h | 41 ++++ drivers/net/ovpn/netlink.c | 156 ++++++++++++++ drivers/net/ovpn/netlink.h | 15 ++ drivers/net/ovpn/ovpnstruct.h | 25 +++ include/uapi/linux/ovpn.h | 111 ++++++++++ 11 files changed, 967 insertions(+), 1 deletion(-)

diff --git a/Documentation/netlink/specs/ovpn.yaml b/Documentation/netlink/specs/ovpn.yaml new file mode 100644 index 0000000000000000000000000000000000000000..d34b4fdff22171b0793204095859f6fce096e457 --- /dev/null +++ b/Documentation/netlink/specs/ovpn.yaml @@ -0,0 +1,372 @@ +# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) +# +# Author: Antonio Quartulli antonio@openvpn.net +# +# Copyright (c) 2024, OpenVPN Inc. +# + +name: ovpn + +protocol: genetlink + +doc: Netlink protocol to control OpenVPN network devices + +definitions: + - + type: const + name: nonce-tail-size + value: 8 + - + type: enum + name: cipher-alg + entries: [ none, aes-gcm, chacha20-poly1305 ] + - + type: enum + name: del-peer-reason + entries: + - teardown + - admindown + - userspace + - expired + - transport-error + - transport-disconnect + - + type: enum + name: key-slot + entries: [ primary, secondary ] + +attribute-sets: + - + name: peer + attributes: + - + name: id + type: u32 + doc: | + The unique ID of the peer in the device context. To be used to identify + peers during operations for a specific device + checks: + max: 0xFFFFFF + - + name: remote-ipv4 + type: u32 + doc: The remote IPv4 address of the peer + byte-order: big-endian + display-hint: ipv4 + - + name: remote-ipv6 + type: binary + doc: The remote IPv6 address of the peer + display-hint: ipv6 + checks: + exact-len: 16 + - + name: remote-ipv6-scope-id + type: u32 + doc: The scope id of the remote IPv6 address of the peer (RFC2553) + - + name: remote-port + type: u16 + doc: The remote port of the peer + byte-order: big-endian + checks: + min: 1 + - + name: socket + type: u32 + doc: The socket to be used to communicate with the peer + - + name: socket-netnsid + type: s32 + doc: The ID of the netns the socket assigned to this peer lives in + - + name: vpn-ipv4 + type: u32 + doc: The IPv4 address assigned to the peer by the server + byte-order: big-endian + display-hint: ipv4 + - + name: vpn-ipv6 + type: binary + doc: The IPv6 address assigned to the peer by the server + display-hint: ipv6 + checks: + exact-len: 16 + - + name: local-ipv4 + type: u32 + doc: The local IPv4 to be used to send packets to the peer (UDP only) + byte-order: big-endian + display-hint: ipv4 + - + name: local-ipv6 + type: binary + doc: The local IPv6 to be used to send packets to the peer (UDP only) + display-hint: ipv6 + checks: + exact-len: 16 + - + name: local-port + type: u16 + doc: The local port to be used to send packets to the peer (UDP only) + byte-order: big-endian + checks: + min: 1 + - + name: keepalive-interval + type: u32 + doc: | + The number of seconds after which a keep alive message is sent to the + peer + - + name: keepalive-timeout + type: u32 + doc: | + The number of seconds from the last activity after which the peer is + assumed dead + - + name: del-reason + type: u32 + doc: The reason why a peer was deleted + enum: del-peer-reason + - + name: vpn-rx-bytes + type: uint + doc: Number of bytes received over the tunnel + - + name: vpn-tx-bytes + type: uint + doc: Number of bytes transmitted over the tunnel + - + name: vpn-rx-packets + type: uint + doc: Number of packets received over the tunnel + - + name: vpn-tx-packets + type: uint + doc: Number of packets transmitted over the tunnel + - + name: link-rx-bytes + type: uint + doc: Number of bytes received at the transport level + - + name: link-tx-bytes + type: uint + doc: Number of bytes transmitted at the transport level + - + name: link-rx-packets + type: u32 + doc: Number of packets received at the transport level + - + name: link-tx-packets + type: u32 + doc: Number of packets transmitted at the transport level + - + name: keyconf + attributes: + - + name: peer-id + type: u32 + doc: | + The unique ID of the peer in the device context. To be used to + identify peers during key operations + checks: + max: 0xFFFFFF + - + name: slot + type: u32 + doc: The slot where the key should be stored + enum: key-slot + - + name: key-id + doc: | + The unique ID of the key in the peer context. Used to fetch the + correct key upon decryption + type: u32 + checks: + max: 7 + - + name: cipher-alg + type: u32 + doc: The cipher to be used when communicating with the peer + enum: cipher-alg + - + name: encrypt-dir + type: nest + doc: Key material for encrypt direction + nested-attributes: keydir + - + name: decrypt-dir + type: nest + doc: Key material for decrypt direction + nested-attributes: keydir + - + name: keydir + attributes: + - + name: cipher-key + type: binary + doc: The actual key to be used by the cipher + checks: + max-len: 256 + - + name: nonce-tail + type: binary + doc: | + Random nonce to be concatenated to the packet ID, in order to + obtain the actual cipher IV + checks: + exact-len: nonce-tail-size + - + name: ovpn + attributes: + - + name: ifindex + type: u32 + doc: Index of the ovpn interface to operate on + - + name: ifname + type: string + doc: Name of the ovpn interface + - + name: peer + type: nest + doc: | + The peer object containing the attributed of interest for the specific + operation + nested-attributes: peer + - + name: keyconf + type: nest + doc: Peer specific cipher configuration + nested-attributes: keyconf + +operations: + list: + - + name: peer-new + attribute-set: ovpn + flags: [ admin-perm ] + doc: Add a remote peer + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - peer + - + name: peer-set + attribute-set: ovpn + flags: [ admin-perm ] + doc: modify a remote peer + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - peer + - + name: peer-get + attribute-set: ovpn + flags: [ admin-perm ] + doc: Retrieve data about existing remote peers (or a specific one) + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - peer + reply: + attributes: + - peer + dump: + request: + attributes: + - ifindex + reply: + attributes: + - peer + - + name: peer-del + attribute-set: ovpn + flags: [ admin-perm ] + doc: Delete existing remote peer + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - peer + - + name: peer-del-ntf + doc: Notification about a peer being deleted + notify: peer-get + mcgrp: peers + + - + name: key-new + attribute-set: ovpn + flags: [ admin-perm ] + doc: Add a cipher key for a specific peer + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - keyconf + - + name: key-get + attribute-set: ovpn + flags: [ admin-perm ] + doc: Retrieve non-sensitive data about peer key and cipher + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - keyconf + reply: + attributes: + - keyconf + - + name: key-swap + attribute-set: ovpn + flags: [ admin-perm ] + doc: Swap primary and secondary session keys for a specific peer + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - keyconf + - + name: key-swap-ntf + notify: key-get + doc: | + Notification about key having exhausted its IV space and requiring + renegotiation + mcgrp: peers + - + name: key-del + attribute-set: ovpn + flags: [ admin-perm ] + doc: Delete cipher key for a specific peer + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - keyconf + +mcast-groups: + list: + - + name: peers diff --git a/MAINTAINERS b/MAINTAINERS index 18747e90f9ff580cb068c265c8fe3cccf7e05615..726da67bb550f8882215f08f784c071283760f3a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17561,7 +17561,9 @@ L: openvpn-devel@lists.sourceforge.net (subscribers-only) L: netdev@vger.kernel.org S: Supported T: git https://github.com/OpenVPN/linux-kernel-ovpn.git +F: Documentation/netlink/specs/ovpn.yaml F: drivers/net/ovpn/ +F: include/uapi/linux/ovpn.h

OPENVSWITCH M: Pravin B Shelar pshelar@ovn.org diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index ae19cf445b29367da680e226f06a341c42c892c2..19305a39e57eede2dc391aa0423702c5321649a6 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -8,3 +8,5 @@

obj-$(CONFIG_OVPN) := ovpn.o ovpn-y += main.o +ovpn-y += netlink.o +ovpn-y += netlink-gen.o diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c index 72c56e73771cdece22e50645b29c79962f06caf3..3475dab4b40f3edd882e05dbdf8badd03d7c78a3 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -7,9 +7,15 @@ * James Yonan james@openvpn.net */

+#include <linux/genetlink.h> #include <linux/module.h> #include <linux/netdevice.h> #include <net/rtnetlink.h> +#include <uapi/linux/ovpn.h> + +#include "ovpnstruct.h" +#include "main.h" +#include "netlink.h"

static const struct net_device_ops ovpn_netdev_ops = { }; @@ -20,7 +26,7 @@ static const struct net_device_ops ovpn_netdev_ops = { * * Return: whether the netdevice is of type 'ovpn' */ -static bool ovpn_dev_is_valid(const struct net_device *dev) +bool ovpn_dev_is_valid(const struct net_device *dev) { return dev->netdev_ops == &ovpn_netdev_ops; } @@ -89,8 +95,16 @@ static int __init ovpn_init(void) goto unreg_netdev; }

+ err = ovpn_nl_register(); + if (err) { + pr_err("ovpn: can't register netlink family: %d\n", err); + goto unreg_rtnl; + } + return 0;

+unreg_rtnl: + rtnl_link_unregister(&ovpn_link_ops); unreg_netdev: unregister_netdevice_notifier(&ovpn_netdev_notifier); return err; @@ -98,6 +112,7 @@ static int __init ovpn_init(void)

static __exit void ovpn_cleanup(void) { + ovpn_nl_unregister(); rtnl_link_unregister(&ovpn_link_ops); unregister_netdevice_notifier(&ovpn_netdev_notifier);

diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h new file mode 100644 index 0000000000000000000000000000000000000000..1a0e83fe1649459289ebec8184c45e757f055dc2 --- /dev/null +++ b/drivers/net/ovpn/main.h @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_MAIN_H_ +#define _NET_OVPN_MAIN_H_ + +bool ovpn_dev_is_valid(const struct net_device *dev); + +#endif /* _NET_OVPN_MAIN_H_ */ diff --git a/drivers/net/ovpn/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c new file mode 100644 index 0000000000000000000000000000000000000000..d0e150bbd5cc4a6f43856a58c845af159acda49c --- /dev/null +++ b/drivers/net/ovpn/netlink-gen.c @@ -0,0 +1,213 @@ +// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/ovpn.yaml */ +/* YNL-GEN kernel source */ + +#include <net/netlink.h> +#include <net/genetlink.h> + +#include "netlink-gen.h" + +#include <uapi/linux/ovpn.h> + +/* Integer value ranges */ +static const struct netlink_range_validation ovpn_a_peer_id_range = { + .max = 16777215ULL, +}; + +static const struct netlink_range_validation ovpn_a_keyconf_peer_id_range = { + .max = 16777215ULL, +}; + +/* Common nested types */ +const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1] = { + [OVPN_A_KEYCONF_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_keyconf_peer_id_range), + [OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1), + [OVPN_A_KEYCONF_KEY_ID] = NLA_POLICY_MAX(NLA_U32, 7), + [OVPN_A_KEYCONF_CIPHER_ALG] = NLA_POLICY_MAX(NLA_U32, 2), + [OVPN_A_KEYCONF_ENCRYPT_DIR] = NLA_POLICY_NESTED(ovpn_keydir_nl_policy), + [OVPN_A_KEYCONF_DECRYPT_DIR] = NLA_POLICY_NESTED(ovpn_keydir_nl_policy), +}; + +const struct nla_policy ovpn_keydir_nl_policy[OVPN_A_KEYDIR_NONCE_TAIL + 1] = { + [OVPN_A_KEYDIR_CIPHER_KEY] = NLA_POLICY_MAX_LEN(256), + [OVPN_A_KEYDIR_NONCE_TAIL] = NLA_POLICY_EXACT_LEN(OVPN_NONCE_TAIL_SIZE), +}; + +const struct nla_policy ovpn_peer_nl_policy[OVPN_A_PEER_LINK_TX_PACKETS + 1] = { + [OVPN_A_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_peer_id_range), + [OVPN_A_PEER_REMOTE_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_REMOTE_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID] = { .type = NLA_U32, }, + [OVPN_A_PEER_REMOTE_PORT] = NLA_POLICY_MIN(NLA_BE16, 1), + [OVPN_A_PEER_SOCKET] = { .type = NLA_U32, }, + [OVPN_A_PEER_SOCKET_NETNSID] = { .type = NLA_S32, }, + [OVPN_A_PEER_VPN_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_VPN_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_LOCAL_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_LOCAL_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_LOCAL_PORT] = NLA_POLICY_MIN(NLA_BE16, 1), + [OVPN_A_PEER_KEEPALIVE_INTERVAL] = { .type = NLA_U32, }, + [OVPN_A_PEER_KEEPALIVE_TIMEOUT] = { .type = NLA_U32, }, + [OVPN_A_PEER_DEL_REASON] = NLA_POLICY_MAX(NLA_U32, 5), + [OVPN_A_PEER_VPN_RX_BYTES] = { .type = NLA_UINT, }, + [OVPN_A_PEER_VPN_TX_BYTES] = { .type = NLA_UINT, }, + [OVPN_A_PEER_VPN_RX_PACKETS] = { .type = NLA_UINT, }, + [OVPN_A_PEER_VPN_TX_PACKETS] = { .type = NLA_UINT, }, + [OVPN_A_PEER_LINK_RX_BYTES] = { .type = NLA_UINT, }, + [OVPN_A_PEER_LINK_TX_BYTES] = { .type = NLA_UINT, }, + [OVPN_A_PEER_LINK_RX_PACKETS] = { .type = NLA_U32, }, + [OVPN_A_PEER_LINK_TX_PACKETS] = { .type = NLA_U32, }, +}; + +/* OVPN_CMD_PEER_NEW - do */ +static const struct nla_policy ovpn_peer_new_nl_policy[OVPN_A_PEER + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, + [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy), +}; + +/* OVPN_CMD_PEER_SET - do */ +static const struct nla_policy ovpn_peer_set_nl_policy[OVPN_A_PEER + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, + [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy), +}; + +/* OVPN_CMD_PEER_GET - do */ +static const struct nla_policy ovpn_peer_get_do_nl_policy[OVPN_A_PEER + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, + [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy), +}; + +/* OVPN_CMD_PEER_GET - dump */ +static const struct nla_policy ovpn_peer_get_dump_nl_policy[OVPN_A_IFINDEX + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, +}; + +/* OVPN_CMD_PEER_DEL - do */ +static const struct nla_policy ovpn_peer_del_nl_policy[OVPN_A_PEER + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, + [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy), +}; + +/* OVPN_CMD_KEY_NEW - do */ +static const struct nla_policy ovpn_key_new_nl_policy[OVPN_A_KEYCONF + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, + [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy), +}; + +/* OVPN_CMD_KEY_GET - do */ +static const struct nla_policy ovpn_key_get_nl_policy[OVPN_A_KEYCONF + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, + [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy), +}; + +/* OVPN_CMD_KEY_SWAP - do */ +static const struct nla_policy ovpn_key_swap_nl_policy[OVPN_A_KEYCONF + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, + [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy), +}; + +/* OVPN_CMD_KEY_DEL - do */ +static const struct nla_policy ovpn_key_del_nl_policy[OVPN_A_KEYCONF + 1] = { + [OVPN_A_IFINDEX] = { .type = NLA_U32, }, + [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy), +}; + +/* Ops table for ovpn */ +static const struct genl_split_ops ovpn_nl_ops[] = { + { + .cmd = OVPN_CMD_PEER_NEW, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_peer_new_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_peer_new_nl_policy, + .maxattr = OVPN_A_PEER, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = OVPN_CMD_PEER_SET, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_peer_set_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_peer_set_nl_policy, + .maxattr = OVPN_A_PEER, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = OVPN_CMD_PEER_GET, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_peer_get_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_peer_get_do_nl_policy, + .maxattr = OVPN_A_PEER, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = OVPN_CMD_PEER_GET, + .dumpit = ovpn_nl_peer_get_dumpit, + .policy = ovpn_peer_get_dump_nl_policy, + .maxattr = OVPN_A_IFINDEX, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DUMP, + }, + { + .cmd = OVPN_CMD_PEER_DEL, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_peer_del_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_peer_del_nl_policy, + .maxattr = OVPN_A_PEER, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = OVPN_CMD_KEY_NEW, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_key_new_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_key_new_nl_policy, + .maxattr = OVPN_A_KEYCONF, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = OVPN_CMD_KEY_GET, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_key_get_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_key_get_nl_policy, + .maxattr = OVPN_A_KEYCONF, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = OVPN_CMD_KEY_SWAP, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_key_swap_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_key_swap_nl_policy, + .maxattr = OVPN_A_KEYCONF, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = OVPN_CMD_KEY_DEL, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_key_del_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_key_del_nl_policy, + .maxattr = OVPN_A_KEYCONF, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, +}; + +static const struct genl_multicast_group ovpn_nl_mcgrps[] = { + [OVPN_NLGRP_PEERS] = { "peers", }, +}; + +struct genl_family ovpn_nl_family __ro_after_init = { + .name = OVPN_FAMILY_NAME, + .version = OVPN_FAMILY_VERSION, + .netnsok = true, + .parallel_ops = true, + .module = THIS_MODULE, + .split_ops = ovpn_nl_ops, + .n_split_ops = ARRAY_SIZE(ovpn_nl_ops), + .mcgrps = ovpn_nl_mcgrps, + .n_mcgrps = ARRAY_SIZE(ovpn_nl_mcgrps), +}; diff --git a/drivers/net/ovpn/netlink-gen.h b/drivers/net/ovpn/netlink-gen.h new file mode 100644 index 0000000000000000000000000000000000000000..66a4e4a0a055b4477b67801ded825e9ec068b0e6 --- /dev/null +++ b/drivers/net/ovpn/netlink-gen.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */ +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/ovpn.yaml */ +/* YNL-GEN kernel header */ + +#ifndef _LINUX_OVPN_GEN_H +#define _LINUX_OVPN_GEN_H + +#include <net/netlink.h> +#include <net/genetlink.h> + +#include <uapi/linux/ovpn.h> + +/* Common nested types */ +extern const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1]; +extern const struct nla_policy ovpn_keydir_nl_policy[OVPN_A_KEYDIR_NONCE_TAIL + 1]; +extern const struct nla_policy ovpn_peer_nl_policy[OVPN_A_PEER_LINK_TX_PACKETS + 1]; + +int ovpn_nl_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb, + struct genl_info *info); +void +ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb, + struct genl_info *info); + +int ovpn_nl_peer_new_doit(struct sk_buff *skb, struct genl_info *info); +int ovpn_nl_peer_set_doit(struct sk_buff *skb, struct genl_info *info); +int ovpn_nl_peer_get_doit(struct sk_buff *skb, struct genl_info *info); +int ovpn_nl_peer_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb); +int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info); +int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info); +int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info); +int ovpn_nl_key_swap_doit(struct sk_buff *skb, struct genl_info *info); +int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info); + +enum { + OVPN_NLGRP_PEERS, +}; + +extern struct genl_family ovpn_nl_family; + +#endif /* _LINUX_OVPN_GEN_H */ diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c new file mode 100644 index 0000000000000000000000000000000000000000..c91368408b805d2bf4f12d64d5c55f4ed6d81343 --- /dev/null +++ b/drivers/net/ovpn/netlink.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#include <linux/netdevice.h> +#include <net/genetlink.h> + +#include <uapi/linux/ovpn.h> + +#include "ovpnstruct.h" +#include "main.h" +#include "netlink.h" +#include "netlink-gen.h" + +MODULE_ALIAS_GENL_FAMILY(OVPN_FAMILY_NAME); + +/** + * ovpn_get_dev_from_attrs - retrieve the ovpn private data from the netdevice + * a netlink message is targeting + * @net: network namespace where to look for the interface + * @info: generic netlink info from the user request + * + * Return: the ovpn private data, if found, or an error otherwise + */ +static struct ovpn_priv * +ovpn_get_dev_from_attrs(struct net *net, const struct genl_info *info) +{ + struct ovpn_priv *ovpn; + struct net_device *dev; + int ifindex; + + if (GENL_REQ_ATTR_CHECK(info, OVPN_A_IFINDEX)) + return ERR_PTR(-EINVAL); + + ifindex = nla_get_u32(info->attrs[OVPN_A_IFINDEX]); + + rcu_read_lock(); + dev = dev_get_by_index_rcu(net, ifindex); + if (!dev) { + rcu_read_unlock(); + NL_SET_ERR_MSG_MOD(info->extack, + "ifindex does not match any interface"); + return ERR_PTR(-ENODEV); + } + + if (!ovpn_dev_is_valid(dev)) { + rcu_read_unlock(); + NL_SET_ERR_MSG_MOD(info->extack, + "specified interface is not ovpn"); + NL_SET_BAD_ATTR(info->extack, info->attrs[OVPN_A_IFINDEX]); + return ERR_PTR(-EINVAL); + } + + ovpn = netdev_priv(dev); + netdev_hold(dev, &ovpn->dev_tracker, GFP_KERNEL); + rcu_read_unlock(); + + return ovpn; +} + +int ovpn_nl_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb, + struct genl_info *info) +{ + struct ovpn_priv *ovpn = ovpn_get_dev_from_attrs(genl_info_net(info), + info); + + if (IS_ERR(ovpn)) + return PTR_ERR(ovpn); + + info->user_ptr[0] = ovpn; + + return 0; +} + +void ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb, + struct genl_info *info) +{ + struct ovpn_priv *ovpn = info->user_ptr[0]; + + if (ovpn) + netdev_put(ovpn->dev, &ovpn->dev_tracker); +} + +int ovpn_nl_peer_new_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_peer_set_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_peer_get_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_peer_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_key_swap_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +/** + * ovpn_nl_register - perform any needed registration in the NL subsustem + * + * Return: 0 on success, a negative error code otherwise + */ +int __init ovpn_nl_register(void) +{ + int ret = genl_register_family(&ovpn_nl_family); + + if (ret) { + pr_err("ovpn: genl_register_family failed: %d\n", ret); + return ret; + } + + return 0; +} + +/** + * ovpn_nl_unregister - undo any module wide netlink registration + */ +void ovpn_nl_unregister(void) +{ + genl_unregister_family(&ovpn_nl_family); +} diff --git a/drivers/net/ovpn/netlink.h b/drivers/net/ovpn/netlink.h new file mode 100644 index 0000000000000000000000000000000000000000..9e87cf11d1e9813b7a75ddf3705ab7d5fabe899f --- /dev/null +++ b/drivers/net/ovpn/netlink.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_NETLINK_H_ +#define _NET_OVPN_NETLINK_H_ + +int ovpn_nl_register(void); +void ovpn_nl_unregister(void); + +#endif /* _NET_OVPN_NETLINK_H_ */ diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h new file mode 100644 index 0000000000000000000000000000000000000000..b4e37e922fe5a5659e030174f1e42b3935967ca0 --- /dev/null +++ b/drivers/net/ovpn/ovpnstruct.h @@ -0,0 +1,25 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2019-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_OVPNSTRUCT_H_ +#define _NET_OVPN_OVPNSTRUCT_H_ + +#include <net/net_trackers.h> + +/** + * struct ovpn_priv - per ovpn interface state + * @dev: the actual netdev representing the tunnel + * @dev_tracker: reference tracker for associated dev + */ +struct ovpn_priv { + struct net_device *dev; + netdevice_tracker dev_tracker; +}; + +#endif /* _NET_OVPN_OVPNSTRUCT_H_ */ diff --git a/include/uapi/linux/ovpn.h b/include/uapi/linux/ovpn.h new file mode 100644 index 0000000000000000000000000000000000000000..8ee54aa2f6ebcc949ce9094746c03c1577ea0ea7 --- /dev/null +++ b/include/uapi/linux/ovpn.h @@ -0,0 +1,111 @@ +/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */ +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/ovpn.yaml */ +/* YNL-GEN uapi header */ + +#ifndef _UAPI_LINUX_OVPN_H +#define _UAPI_LINUX_OVPN_H + +#define OVPN_FAMILY_NAME "ovpn" +#define OVPN_FAMILY_VERSION 1 + +#define OVPN_NONCE_TAIL_SIZE 8 + +enum ovpn_cipher_alg { + OVPN_CIPHER_ALG_NONE, + OVPN_CIPHER_ALG_AES_GCM, + OVPN_CIPHER_ALG_CHACHA20_POLY1305, +}; + +enum ovpn_del_peer_reason { + OVPN_DEL_PEER_REASON_TEARDOWN, + OVPN_DEL_PEER_REASON_ADMINDOWN, + OVPN_DEL_PEER_REASON_USERSPACE, + OVPN_DEL_PEER_REASON_EXPIRED, + OVPN_DEL_PEER_REASON_TRANSPORT_ERROR, + OVPN_DEL_PEER_REASON_TRANSPORT_DISCONNECT, +}; + +enum ovpn_key_slot { + OVPN_KEY_SLOT_PRIMARY, + OVPN_KEY_SLOT_SECONDARY, +}; + +enum { + OVPN_A_PEER_ID = 1, + OVPN_A_PEER_REMOTE_IPV4, + OVPN_A_PEER_REMOTE_IPV6, + OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID, + OVPN_A_PEER_REMOTE_PORT, + OVPN_A_PEER_SOCKET, + OVPN_A_PEER_SOCKET_NETNSID, + OVPN_A_PEER_VPN_IPV4, + OVPN_A_PEER_VPN_IPV6, + OVPN_A_PEER_LOCAL_IPV4, + OVPN_A_PEER_LOCAL_IPV6, + OVPN_A_PEER_LOCAL_PORT, + OVPN_A_PEER_KEEPALIVE_INTERVAL, + OVPN_A_PEER_KEEPALIVE_TIMEOUT, + OVPN_A_PEER_DEL_REASON, + OVPN_A_PEER_VPN_RX_BYTES, + OVPN_A_PEER_VPN_TX_BYTES, + OVPN_A_PEER_VPN_RX_PACKETS, + OVPN_A_PEER_VPN_TX_PACKETS, + OVPN_A_PEER_LINK_RX_BYTES, + OVPN_A_PEER_LINK_TX_BYTES, + OVPN_A_PEER_LINK_RX_PACKETS, + OVPN_A_PEER_LINK_TX_PACKETS, + + __OVPN_A_PEER_MAX, + OVPN_A_PEER_MAX = (__OVPN_A_PEER_MAX - 1) +}; + +enum { + OVPN_A_KEYCONF_PEER_ID = 1, + OVPN_A_KEYCONF_SLOT, + OVPN_A_KEYCONF_KEY_ID, + OVPN_A_KEYCONF_CIPHER_ALG, + OVPN_A_KEYCONF_ENCRYPT_DIR, + OVPN_A_KEYCONF_DECRYPT_DIR, + + __OVPN_A_KEYCONF_MAX, + OVPN_A_KEYCONF_MAX = (__OVPN_A_KEYCONF_MAX - 1) +}; + +enum { + OVPN_A_KEYDIR_CIPHER_KEY = 1, + OVPN_A_KEYDIR_NONCE_TAIL, + + __OVPN_A_KEYDIR_MAX, + OVPN_A_KEYDIR_MAX = (__OVPN_A_KEYDIR_MAX - 1) +}; + +enum { + OVPN_A_IFINDEX = 1, + OVPN_A_IFNAME, + OVPN_A_PEER, + OVPN_A_KEYCONF, + + __OVPN_A_MAX, + OVPN_A_MAX = (__OVPN_A_MAX - 1) +}; + +enum { + OVPN_CMD_PEER_NEW = 1, + OVPN_CMD_PEER_SET, + OVPN_CMD_PEER_GET, + OVPN_CMD_PEER_DEL, + OVPN_CMD_PEER_DEL_NTF, + OVPN_CMD_KEY_NEW, + OVPN_CMD_KEY_GET, + OVPN_CMD_KEY_SWAP, + OVPN_CMD_KEY_SWAP_NTF, + OVPN_CMD_KEY_DEL, + + __OVPN_CMD_MAX, + OVPN_CMD_MAX = (__OVPN_CMD_MAX - 1) +}; + +#define OVPN_MCGRP_PEERS "peers" + +#endif /* _UAPI_LINUX_OVPN_H */

An ovpn interface configured in MP mode will keep carrier always on and let the user decide when to bring it administratively up and down.

This way a MP node (i.e. a server) will keep its interface always up and running, even when no peer is connected.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/main.c | 9 +++++++++ 1 file changed, 9 insertions(+)

diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c index 60954c5b2b9254db1d24d01ac383935765c7ce5b..274d6166741ef2d6275a252d0c042bc66f8f41f7 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -23,6 +23,15 @@

static int ovpn_net_open(struct net_device *dev) { + struct ovpn_priv *ovpn = netdev_priv(dev); + + /* carrier for P2P interfaces is switched on and off when + * the peer is added or deleted. + * + * in case of P2MP interfaces we just keep the carrier always on + */ + if (ovpn->mode == OVPN_MODE_MP) + netif_carrier_on(dev); netif_tx_start_all_queues(dev); return 0; }

This specific structure is used in the ovpn kernel module to wrap and carry around a standard kernel socket.

ovpn takes ownership of passed sockets and therefore an ovpn specific objects is attached to them for status tracking purposes.

Initially only UDP support is introduced. TCP will come in a later patch.

Cc: willemdebruijn.kernel@gmail.com Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/Makefile | 2 + drivers/net/ovpn/socket.c | 119 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/socket.h | 48 +++++++++++++++++++ drivers/net/ovpn/udp.c | 65 +++++++++++++++++++++++++ drivers/net/ovpn/udp.h | 17 +++++++ include/uapi/linux/udp.h | 1 + 6 files changed, 252 insertions(+)

diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index ce13499b3e1775a7f2a9ce16c6cb0aa088f93685..56bddc9bef83e0befde6af3c3565bb91731d7b22 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -13,3 +13,5 @@ ovpn-y += io.o ovpn-y += netlink.o ovpn-y += netlink-gen.o ovpn-y += peer.o +ovpn-y += socket.o +ovpn-y += udp.o diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c new file mode 100644 index 0000000000000000000000000000000000000000..0abac02e13fb4ef1e212dacae075d5b58e872d34 --- /dev/null +++ b/drivers/net/ovpn/socket.c @@ -0,0 +1,119 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/udp.h> + +#include "ovpnstruct.h" +#include "main.h" +#include "io.h" +#include "peer.h" +#include "socket.h" +#include "udp.h" + +static void ovpn_socket_detach(struct socket *sock) +{ + if (!sock) + return; + + sockfd_put(sock); +} + +/** + * ovpn_socket_release_kref - kref_put callback + * @kref: the kref object + */ +void ovpn_socket_release_kref(struct kref *kref) +{ + struct ovpn_socket *sock = container_of(kref, struct ovpn_socket, + refcount); + + ovpn_socket_detach(sock->sock); + kfree_rcu(sock, rcu); +} + +static bool ovpn_socket_hold(struct ovpn_socket *sock) +{ + return kref_get_unless_zero(&sock->refcount); +} + +static struct ovpn_socket *ovpn_socket_get(struct socket *sock) +{ + struct ovpn_socket *ovpn_sock; + + rcu_read_lock(); + ovpn_sock = rcu_dereference_sk_user_data(sock->sk); + if (WARN_ON(!ovpn_socket_hold(ovpn_sock))) + ovpn_sock = NULL; + rcu_read_unlock(); + + return ovpn_sock; +} + +static int ovpn_socket_attach(struct socket *sock, struct ovpn_peer *peer) +{ + int ret = -EOPNOTSUPP; + + if (!sock || !peer) + return -EINVAL; + + if (sock->sk->sk_protocol == IPPROTO_UDP) + ret = ovpn_udp_socket_attach(sock, peer->ovpn); + + return ret; +} + +/** + * ovpn_socket_new - create a new socket and initialize it + * @sock: the kernel socket to embed + * @peer: the peer reachable via this socket + * + * Return: an openvpn socket on success or a negative error code otherwise + */ +struct ovpn_socket *ovpn_socket_new(struct socket *sock, struct ovpn_peer *peer) +{ + struct ovpn_socket *ovpn_sock; + int ret; + + ret = ovpn_socket_attach(sock, peer); + if (ret < 0 && ret != -EALREADY) + return ERR_PTR(ret); + + /* if this socket is already owned by this interface, just increase the + * refcounter and use it as expected. + * + * Since UDP sockets can be used to talk to multiple remote endpoints, + * openvpn normally instantiates only one socket and shares it among all + * its peers. For this reason, when we find out that a socket is already + * used for some other peer in *this* instance, we can happily increase + * its refcounter and use it normally. + */ + if (ret == -EALREADY) { + /* caller is expected to increase the sock refcounter before + * passing it to this function. For this reason we drop it if + * not needed, like when this socket is already owned. + */ + ovpn_sock = ovpn_socket_get(sock); + sockfd_put(sock); + return ovpn_sock; + } + + ovpn_sock = kzalloc(sizeof(*ovpn_sock), GFP_KERNEL); + if (!ovpn_sock) + return ERR_PTR(-ENOMEM); + + ovpn_sock->ovpn = peer->ovpn; + ovpn_sock->sock = sock; + kref_init(&ovpn_sock->refcount); + + rcu_assign_sk_user_data(sock->sk, ovpn_sock); + + return ovpn_sock; +} diff --git a/drivers/net/ovpn/socket.h b/drivers/net/ovpn/socket.h new file mode 100644 index 0000000000000000000000000000000000000000..904814d2b9e9f2b0773bf942372bcbe904ef5474 --- /dev/null +++ b/drivers/net/ovpn/socket.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_SOCK_H_ +#define _NET_OVPN_SOCK_H_ + +#include <linux/net.h> +#include <linux/kref.h> +#include <net/sock.h> + +struct ovpn_priv; +struct ovpn_peer; + +/** + * struct ovpn_socket - a kernel socket referenced in the ovpn code + * @ovpn: ovpn instance owning this socket (UDP only) + * @sock: the low level sock object + * @refcount: amount of contexts currently referencing this object + * @rcu: member used to schedule RCU destructor callback + */ +struct ovpn_socket { + struct ovpn_priv *ovpn; + struct socket *sock; + struct kref refcount; + struct rcu_head rcu; +}; + +void ovpn_socket_release_kref(struct kref *kref); + +/** + * ovpn_socket_put - decrease reference counter + * @sock: the socket whose reference counter should be decreased + */ +static inline void ovpn_socket_put(struct ovpn_socket *sock) +{ + kref_put(&sock->refcount, ovpn_socket_release_kref); +} + +struct ovpn_socket *ovpn_socket_new(struct socket *sock, + struct ovpn_peer *peer); + +#endif /* _NET_OVPN_SOCK_H_ */ diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c new file mode 100644 index 0000000000000000000000000000000000000000..c00e07f148d72ff737e732028fd73f82a507fb57 --- /dev/null +++ b/drivers/net/ovpn/udp.c @@ -0,0 +1,65 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2019-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#include <linux/netdevice.h> +#include <linux/socket.h> +#include <linux/udp.h> +#include <net/udp.h> + +#include "ovpnstruct.h" +#include "main.h" +#include "socket.h" +#include "udp.h" + +/** + * ovpn_udp_socket_attach - set udp-tunnel CBs on socket and link it to ovpn + * @sock: socket to configure + * @ovpn: the openvp instance to link + * + * After invoking this function, the sock will be controlled by ovpn so that + * any incoming packet may be processed by ovpn first. + * + * Return: 0 on success or a negative error code otherwise + */ +int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_priv *ovpn) +{ + struct ovpn_socket *old_data; + int ret = 0; + + /* make sure no pre-existing encapsulation handler exists */ + rcu_read_lock(); + old_data = rcu_dereference_sk_user_data(sock->sk); + if (!old_data) { + /* socket is currently unused - we can take it */ + rcu_read_unlock(); + return 0; + } + + /* socket is in use. We need to understand if it's owned by this ovpn + * instance or by something else. + * In the former case, we can increase the refcounter and happily + * use it, because the same UDP socket is expected to be shared among + * different peers. + * + * Unlikely TCP, a single UDP socket can be used to talk to many remote + * hosts and therefore openvpn instantiates one only for all its peers + */ + if ((READ_ONCE(udp_sk(sock->sk)->encap_type) == UDP_ENCAP_OVPNINUDP) && + old_data->ovpn == ovpn) { + netdev_dbg(ovpn->dev, + "provided socket already owned by this interface\n"); + ret = -EALREADY; + } else { + netdev_dbg(ovpn->dev, + "provided socket already taken by other user\n"); + ret = -EBUSY; + } + rcu_read_unlock(); + + return ret; +} diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h new file mode 100644 index 0000000000000000000000000000000000000000..3c48a06f15eed624aec0a2a7b871f0e7f3004137 --- /dev/null +++ b/drivers/net/ovpn/udp.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2019-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_UDP_H_ +#define _NET_OVPN_UDP_H_ + +struct ovpn_priv; +struct socket; + +int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_priv *ovpn); + +#endif /* _NET_OVPN_UDP_H_ */ diff --git a/include/uapi/linux/udp.h b/include/uapi/linux/udp.h index d85d671deed3c78f6969189281b9083dcac000c6..edca3e430305a6bffc34e617421f1f3071582e69 100644 --- a/include/uapi/linux/udp.h +++ b/include/uapi/linux/udp.h @@ -43,5 +43,6 @@ struct udphdr { #define UDP_ENCAP_GTP1U 5 /* 3GPP TS 29.060 */ #define UDP_ENCAP_RXRPC 6 #define TCP_ENCAP_ESPINTCP 7 /* Yikes, this is really xfrm encap types. */ +#define UDP_ENCAP_OVPNINUDP 8 /* OpenVPN traffic */

#endif /* _UAPI_LINUX_UDP_H */

Packets sent over the ovpn interface are processed and transmitted to the connected peer, if any.

Implementation is UDP only. TCP will be added by a later patch.

Note: no crypto/encapsulation exists yet. Packets are just captured and sent.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/Kconfig | 1 + drivers/net/ovpn/io.c | 129 +++++++++++++++++++++++++- drivers/net/ovpn/peer.c | 35 ++++++++ drivers/net/ovpn/peer.h | 4 + drivers/net/ovpn/skb.h | 55 ++++++++++++ drivers/net/ovpn/udp.c | 234 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/udp.h | 5 ++ 7 files changed, 462 insertions(+), 1 deletion(-)

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index d6c1810f042e222143f53563a8d8df4bc9df27ed..f4f985fc003373ddc14dc18f8b3f73295a3ae0a6 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -119,6 +119,7 @@ config OVPN tristate "OpenVPN data channel offload" depends on NET && INET select DST_CACHE + select NET_UDP_TUNNEL help This module enhances the performance of the OpenVPN userspace software by offloading the data channel processing to kernelspace. diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index ad3813419c33cbdfe7e8ad6f5c8b444a3540a69f..2a3dbc723813a14070159318097755cc7ea3f216 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -9,14 +9,141 @@

#include <linux/netdevice.h> #include <linux/skbuff.h> +#include <net/gso.h>

#include "io.h" +#include "ovpnstruct.h" +#include "peer.h" +#include "udp.h" +#include "skb.h" +#include "socket.h" + +static void ovpn_encrypt_post(struct sk_buff *skb, int ret) +{ + struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer; + + if (unlikely(ret < 0)) + goto err; + + skb_mark_not_on_list(skb); + + switch (peer->sock->sock->sk->sk_protocol) { + case IPPROTO_UDP: + ovpn_udp_send_skb(peer, skb); + break; + default: + /* no transport configured yet */ + goto err; + } + /* skb passed down the stack - don't free it */ + skb = NULL; +err: + if (unlikely(skb)) + dev_core_stats_tx_dropped_inc(peer->ovpn->dev); + ovpn_peer_put(peer); + kfree_skb(skb); +} + +static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb) +{ + ovpn_skb_cb(skb)->peer = peer; + + /* take a reference to the peer because the crypto code may run async. + * ovpn_encrypt_post() will release it upon completion + */ + if (unlikely(!ovpn_peer_hold(peer))) { + DEBUG_NET_WARN_ON_ONCE(1); + return false; + } + + ovpn_encrypt_post(skb, 0); + return true; +} + +/* send skb to connected peer, if any */ +static void ovpn_send(struct ovpn_priv *ovpn, struct sk_buff *skb, + struct ovpn_peer *peer) +{ + struct sk_buff *curr, *next; + + /* this might be a GSO-segmented skb list: process each skb + * independently + */ + skb_list_walk_safe(skb, curr, next) { + if (unlikely(!ovpn_encrypt_one(peer, curr))) { + dev_core_stats_tx_dropped_inc(ovpn->dev); + kfree_skb(curr); + } + } + + ovpn_peer_put(peer); +}

/* Send user data to the network */ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev) { + struct ovpn_priv *ovpn = netdev_priv(dev); + struct sk_buff *segments, *curr, *next; + struct sk_buff_head skb_list; + struct ovpn_peer *peer; + __be16 proto; + int ret; + + /* reset netfilter state */ + nf_reset_ct(skb); + + /* verify IP header size in network packet */ + proto = ovpn_ip_check_protocol(skb); + if (unlikely(!proto || skb->protocol != proto)) + goto drop; + + if (skb_is_gso(skb)) { + segments = skb_gso_segment(skb, 0); + if (IS_ERR(segments)) { + ret = PTR_ERR(segments); + net_err_ratelimited("%s: cannot segment payload packet: %d\n", + netdev_name(dev), ret); + goto drop; + } + + consume_skb(skb); + skb = segments; + } + + /* from this moment on, "skb" might be a list */ + + __skb_queue_head_init(&skb_list); + skb_list_walk_safe(skb, curr, next) { + skb_mark_not_on_list(curr); + + curr = skb_share_check(curr, GFP_ATOMIC); + if (unlikely(!curr)) { + net_err_ratelimited("%s: skb_share_check failed for payload packet\n", + netdev_name(dev)); + dev_core_stats_tx_dropped_inc(ovpn->dev); + continue; + } + + __skb_queue_tail(&skb_list, curr); + } + skb_list.prev->next = NULL; + + /* retrieve peer serving the destination IP of this packet */ + peer = ovpn_peer_get_by_dst(ovpn, skb); + if (unlikely(!peer)) { + net_dbg_ratelimited("%s: no peer to send data to\n", + netdev_name(ovpn->dev)); + goto drop; + } + + ovpn_send(ovpn, skb_list.next, peer); + + return NETDEV_TX_OK; + +drop: + dev_core_stats_tx_dropped_inc(ovpn->dev); skb_tx_error(skb); - kfree_skb(skb); + kfree_skb_list(skb); return NET_XMIT_DROP; } diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index 427276dd910f4658dd0bfb272b13631976df622d..d89c82aae2c7646f8c40cdde5bfe364c8b46c659 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -16,6 +16,7 @@ #include "main.h" #include "netlink.h" #include "peer.h" +#include "socket.h"

/** * ovpn_peer_new - allocate and initialize a new peer object @@ -253,6 +254,38 @@ struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id) return peer; }

+/** + * ovpn_peer_get_by_dst - Lookup peer to send skb to + * @ovpn: the private data representing the current VPN session + * @skb: the skb to extract the destination address from + * + * This function takes a tunnel packet and looks up the peer to send it to + * after encapsulation. The skb is expected to be the in-tunnel packet, without + * any OpenVPN related header. + * + * Assume that the IP header is accessible in the skb data. + * + * Return: the peer if found or NULL otherwise. + */ +struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn, + struct sk_buff *skb) +{ + struct ovpn_peer *peer = NULL; + + /* in P2P mode, no matter the destination, packets are always sent to + * the single peer listening on the other side + */ + if (ovpn->mode == OVPN_MODE_P2P) { + rcu_read_lock(); + peer = rcu_dereference(ovpn->peer); + if (unlikely(peer && !ovpn_peer_hold(peer))) + peer = NULL; + rcu_read_unlock(); + } + + return peer; +} + /** * ovpn_peer_add_p2p - add peer to related tables in a P2P instance * @ovpn: the instance to add the peer to @@ -318,6 +351,8 @@ static void ovpn_peer_remove(struct ovpn_peer *peer, }

peer->delete_reason = reason; + if (peer->sock) + ovpn_socket_put(peer->sock);

/* reference from ovpn->peer or hashtable dropped */ ovpn_peer_put(peer); diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index c3458732b2cfcd439644423ec8cd77595f9ed5f3..24de7a69e371a521bed48a8ef3116350ea3e9560 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -19,6 +19,7 @@ * @vpn_addrs: IP addresses assigned over the tunnel * @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel * @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel + * @sock: the socket being used to talk to this peer * @dst_cache: cache for dst_entry used to send to peer * @bind: remote peer binding * @delete_reason: why peer was deleted (i.e. timeout, transport error, ..) @@ -34,6 +35,7 @@ struct ovpn_peer { struct in_addr ipv4; struct in6_addr ipv6; } vpn_addrs; + struct ovpn_socket *sock; struct dst_cache dst_cache; struct ovpn_bind __rcu *bind; enum ovpn_del_peer_reason delete_reason; @@ -74,5 +76,7 @@ void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn, struct sk_buff *skb); struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id); +struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn, + struct sk_buff *skb);

#endif /* _NET_OVPN_OVPNPEER_H_ */ diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h new file mode 100644 index 0000000000000000000000000000000000000000..af7b1f5b0ee6033ce980978667c3ee99a90e1d1b --- /dev/null +++ b/drivers/net/ovpn/skb.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + * James Yonan james@openvpn.net + */ + +#ifndef _NET_OVPN_SKB_H_ +#define _NET_OVPN_SKB_H_ + +#include <linux/in.h> +#include <linux/in6.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/skbuff.h> +#include <linux/socket.h> +#include <linux/types.h> + +struct ovpn_cb { + struct ovpn_peer *peer; +}; + +static inline struct ovpn_cb *ovpn_skb_cb(struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(struct ovpn_cb) > sizeof(skb->cb)); + return (struct ovpn_cb *)skb->cb; +} + +/* Return IP protocol version from skb header. + * Return 0 if protocol is not IPv4/IPv6 or cannot be read. + */ +static inline __be16 ovpn_ip_check_protocol(struct sk_buff *skb) +{ + __be16 proto = 0; + + /* skb could be non-linear, + * make sure IP header is in non-fragmented part + */ + if (!pskb_network_may_pull(skb, sizeof(struct iphdr))) + return 0; + + if (ip_hdr(skb)->version == 4) { + proto = htons(ETH_P_IP); + } else if (ip_hdr(skb)->version == 6) { + if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr))) + return 0; + proto = htons(ETH_P_IPV6); + } + + return proto; +} + +#endif /* _NET_OVPN_SKB_H_ */ diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c index c00e07f148d72ff737e732028fd73f82a507fb57..c0e7aa289ad3345fcd91e7c890f70961300c356f 100644 --- a/drivers/net/ovpn/udp.c +++ b/drivers/net/ovpn/udp.c @@ -7,15 +7,249 @@ */

#include <linux/netdevice.h> +#include <linux/inetdevice.h> +#include <linux/skbuff.h> #include <linux/socket.h> #include <linux/udp.h> +#include <net/addrconf.h> +#include <net/dst_cache.h> +#include <net/route.h> +#include <net/ipv6_stubs.h> #include <net/udp.h> +#include <net/udp_tunnel.h>

#include "ovpnstruct.h" #include "main.h" +#include "bind.h" +#include "io.h" +#include "peer.h" #include "socket.h" #include "udp.h"

+/** + * ovpn_udp4_output - send IPv4 packet over udp socket + * @peer: the destination peer + * @bind: the binding related to the destination peer + * @cache: dst cache + * @sk: the socket to send the packet over + * @skb: the packet to send + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_udp4_output(struct ovpn_peer *peer, struct ovpn_bind *bind, + struct dst_cache *cache, struct sock *sk, + struct sk_buff *skb) +{ + struct rtable *rt; + struct flowi4 fl = { + .saddr = bind->local.ipv4.s_addr, + .daddr = bind->remote.in4.sin_addr.s_addr, + .fl4_sport = inet_sk(sk)->inet_sport, + .fl4_dport = bind->remote.in4.sin_port, + .flowi4_proto = sk->sk_protocol, + .flowi4_mark = sk->sk_mark, + }; + int ret; + + local_bh_disable(); + rt = dst_cache_get_ip4(cache, &fl.saddr); + if (rt) + goto transmit; + + if (unlikely(!inet_confirm_addr(sock_net(sk), NULL, 0, fl.saddr, + RT_SCOPE_HOST))) { + /* we may end up here when the cached address is not usable + * anymore. In this case we reset address/cache and perform a + * new look up + */ + fl.saddr = 0; + spin_lock_bh(&peer->lock); + bind->local.ipv4.s_addr = 0; + spin_unlock_bh(&peer->lock); + dst_cache_reset(cache); + } + + rt = ip_route_output_flow(sock_net(sk), &fl, sk); + if (IS_ERR(rt) && PTR_ERR(rt) == -EINVAL) { + fl.saddr = 0; + spin_lock_bh(&peer->lock); + bind->local.ipv4.s_addr = 0; + spin_unlock_bh(&peer->lock); + dst_cache_reset(cache); + + rt = ip_route_output_flow(sock_net(sk), &fl, sk); + } + + if (IS_ERR(rt)) { + ret = PTR_ERR(rt); + net_dbg_ratelimited("%s: no route to host %pISpc: %d\n", + netdev_name(peer->ovpn->dev), + &bind->remote.in4, + ret); + goto err; + } + dst_cache_set_ip4(cache, &rt->dst, fl.saddr); + +transmit: + udp_tunnel_xmit_skb(rt, sk, skb, fl.saddr, fl.daddr, 0, + ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport, + fl.fl4_dport, false, sk->sk_no_check_tx); + ret = 0; +err: + local_bh_enable(); + return ret; +} + +#if IS_ENABLED(CONFIG_IPV6) +/** + * ovpn_udp6_output - send IPv6 packet over udp socket + * @peer: the destination peer + * @bind: the binding related to the destination peer + * @cache: dst cache + * @sk: the socket to send the packet over + * @skb: the packet to send + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_udp6_output(struct ovpn_peer *peer, struct ovpn_bind *bind, + struct dst_cache *cache, struct sock *sk, + struct sk_buff *skb) +{ + struct dst_entry *dst; + int ret; + + struct flowi6 fl = { + .saddr = bind->local.ipv6, + .daddr = bind->remote.in6.sin6_addr, + .fl6_sport = inet_sk(sk)->inet_sport, + .fl6_dport = bind->remote.in6.sin6_port, + .flowi6_proto = sk->sk_protocol, + .flowi6_mark = sk->sk_mark, + .flowi6_oif = bind->remote.in6.sin6_scope_id, + }; + + local_bh_disable(); + dst = dst_cache_get_ip6(cache, &fl.saddr); + if (dst) + goto transmit; + + if (unlikely(!ipv6_chk_addr(sock_net(sk), &fl.saddr, NULL, 0))) { + /* we may end up here when the cached address is not usable + * anymore. In this case we reset address/cache and perform a + * new look up + */ + fl.saddr = in6addr_any; + spin_lock_bh(&peer->lock); + bind->local.ipv6 = in6addr_any; + spin_unlock_bh(&peer->lock); + dst_cache_reset(cache); + } + + dst = ipv6_stub->ipv6_dst_lookup_flow(sock_net(sk), sk, &fl, NULL); + if (IS_ERR(dst)) { + ret = PTR_ERR(dst); + net_dbg_ratelimited("%s: no route to host %pISpc: %d\n", + netdev_name(peer->ovpn->dev), + &bind->remote.in6, ret); + goto err; + } + dst_cache_set_ip6(cache, dst, &fl.saddr); + +transmit: + udp_tunnel6_xmit_skb(dst, sk, skb, skb->dev, &fl.saddr, &fl.daddr, 0, + ip6_dst_hoplimit(dst), 0, fl.fl6_sport, + fl.fl6_dport, udp_get_no_check6_tx(sk)); + ret = 0; +err: + local_bh_enable(); + return ret; +} +#endif + +/** + * ovpn_udp_output - transmit skb using udp-tunnel + * @peer: the destination peer + * @cache: dst cache + * @sk: the socket to send the packet over + * @skb: the packet to send + * + * rcu_read_lock should be held on entry. + * On return, the skb is consumed. + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_udp_output(struct ovpn_peer *peer, struct dst_cache *cache, + struct sock *sk, struct sk_buff *skb) +{ + struct ovpn_bind *bind; + int ret; + + /* set sk to null if skb is already orphaned */ + if (!skb->destructor) + skb->sk = NULL; + + /* always permit openvpn-created packets to be (outside) fragmented */ + skb->ignore_df = 1; + + rcu_read_lock(); + bind = rcu_dereference(peer->bind); + if (unlikely(!bind)) { + net_warn_ratelimited("%s: no bind for remote peer %u\n", + netdev_name(peer->ovpn->dev), peer->id); + ret = -ENODEV; + goto out; + } + + switch (bind->remote.in4.sin_family) { + case AF_INET: + ret = ovpn_udp4_output(peer, bind, cache, sk, skb); + break; +#if IS_ENABLED(CONFIG_IPV6) + case AF_INET6: + ret = ovpn_udp6_output(peer, bind, cache, sk, skb); + break; +#endif + default: + ret = -EAFNOSUPPORT; + break; + } + +out: + rcu_read_unlock(); + return ret; +} + +/** + * ovpn_udp_send_skb - prepare skb and send it over via UDP + * @peer: the destination peer + * @skb: the packet to send + */ +void ovpn_udp_send_skb(struct ovpn_peer *peer, struct sk_buff *skb) +{ + struct socket *sock; + int ret = -1; + + skb->dev = peer->ovpn->dev; + /* no checksum performed at this layer */ + skb->ip_summed = CHECKSUM_NONE; + + /* get socket info */ + sock = peer->sock->sock; + if (unlikely(!sock)) { + net_warn_ratelimited("%s: no sock for remote peer %u\n", + netdev_name(peer->ovpn->dev), peer->id); + goto out; + } + + /* crypto layer -> transport (UDP) */ + ret = ovpn_udp_output(peer, &peer->dst_cache, sock->sk, skb); +out: + if (unlikely(ret < 0)) { + kfree_skb(skb); + return; + } +} + /** * ovpn_udp_socket_attach - set udp-tunnel CBs on socket and link it to ovpn * @sock: socket to configure diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h index 3c48a06f15eed624aec0a2a7b871f0e7f3004137..44ebeb82325dc4d172da7e29fb36f21a5609ea8d 100644 --- a/drivers/net/ovpn/udp.h +++ b/drivers/net/ovpn/udp.h @@ -9,9 +9,14 @@ #ifndef _NET_OVPN_UDP_H_ #define _NET_OVPN_UDP_H_

+#include <net/sock.h> + +struct ovpn_peer; struct ovpn_priv; struct socket;

int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_priv *ovpn);

+void ovpn_udp_send_skb(struct ovpn_peer *peer, struct sk_buff *skb); + #endif /* _NET_OVPN_UDP_H_ */

This change implements encryption/decryption and encapsulation/decapsulation of OpenVPN packets.

Support for generic crypto state is added along with a wrapper for the AEAD crypto kernel API.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/Kconfig | 4 + drivers/net/ovpn/Makefile | 3 + drivers/net/ovpn/crypto.c | 152 +++++++++++++++++ drivers/net/ovpn/crypto.h | 139 ++++++++++++++++ drivers/net/ovpn/crypto_aead.c | 366 +++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/crypto_aead.h | 31 ++++ drivers/net/ovpn/io.c | 149 +++++++++++++++-- drivers/net/ovpn/io.h | 3 + drivers/net/ovpn/peer.c | 29 ++++ drivers/net/ovpn/peer.h | 6 + drivers/net/ovpn/pktid.c | 129 +++++++++++++++ drivers/net/ovpn/pktid.h | 87 ++++++++++ drivers/net/ovpn/proto.h | 32 ++++ drivers/net/ovpn/skb.h | 4 + 14 files changed, 1123 insertions(+), 11 deletions(-)

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index f4f985fc003373ddc14dc18f8b3f73295a3ae0a6..7d274ec48983f0ec460094ec81dc177c56f37ffe 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -120,6 +120,10 @@ config OVPN depends on NET && INET select DST_CACHE select NET_UDP_TUNNEL + select CRYPTO + select CRYPTO_AES + select CRYPTO_GCM + select CRYPTO_CHACHA20POLY1305 help This module enhances the performance of the OpenVPN userspace software by offloading the data channel processing to kernelspace. diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index 56bddc9bef83e0befde6af3c3565bb91731d7b22..ccdaeced1982c851475657860a005ff2b9dfbd13 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -8,10 +8,13 @@

obj-$(CONFIG_OVPN) := ovpn.o ovpn-y += bind.o +ovpn-y += crypto.o +ovpn-y += crypto_aead.o ovpn-y += main.o ovpn-y += io.o ovpn-y += netlink.o ovpn-y += netlink-gen.o ovpn-y += peer.o +ovpn-y += pktid.o ovpn-y += socket.o ovpn-y += udp.o diff --git a/drivers/net/ovpn/crypto.c b/drivers/net/ovpn/crypto.c new file mode 100644 index 0000000000000000000000000000000000000000..fabc19994ba34260753911ac7d3e50b643b9b89f --- /dev/null +++ b/drivers/net/ovpn/crypto.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#include <linux/types.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <uapi/linux/ovpn.h> + +#include "ovpnstruct.h" +#include "main.h" +#include "pktid.h" +#include "crypto_aead.h" +#include "crypto.h" + +static void ovpn_ks_destroy_rcu(struct rcu_head *head) +{ + struct ovpn_crypto_key_slot *ks; + + ks = container_of(head, struct ovpn_crypto_key_slot, rcu); + ovpn_aead_crypto_key_slot_destroy(ks); +} + +void ovpn_crypto_key_slot_release(struct kref *kref) +{ + struct ovpn_crypto_key_slot *ks; + + ks = container_of(kref, struct ovpn_crypto_key_slot, refcount); + call_rcu(&ks->rcu, ovpn_ks_destroy_rcu); +} + +/* can only be invoked when all peer references have been dropped (i.e. RCU + * release routine) + */ +void ovpn_crypto_state_release(struct ovpn_crypto_state *cs) +{ + struct ovpn_crypto_key_slot *ks; + + ks = rcu_access_pointer(cs->slots[0]); + if (ks) { + RCU_INIT_POINTER(cs->slots[0], NULL); + ovpn_crypto_key_slot_put(ks); + } + + ks = rcu_access_pointer(cs->slots[1]); + if (ks) { + RCU_INIT_POINTER(cs->slots[1], NULL); + ovpn_crypto_key_slot_put(ks); + } +} + +/* Reset the ovpn_crypto_state object in a way that is atomic + * to RCU readers. + */ +int ovpn_crypto_state_reset(struct ovpn_crypto_state *cs, + const struct ovpn_peer_key_reset *pkr) +{ + struct ovpn_crypto_key_slot *old = NULL, *new; + u8 idx; + + if (pkr->slot != OVPN_KEY_SLOT_PRIMARY && + pkr->slot != OVPN_KEY_SLOT_SECONDARY) + return -EINVAL; + + new = ovpn_aead_crypto_key_slot_new(&pkr->key); + if (IS_ERR(new)) + return PTR_ERR(new); + + spin_lock_bh(&cs->lock); + idx = cs->primary_idx; + switch (pkr->slot) { + case OVPN_KEY_SLOT_PRIMARY: + old = rcu_replace_pointer(cs->slots[idx], new, + lockdep_is_held(&cs->lock)); + break; + case OVPN_KEY_SLOT_SECONDARY: + old = rcu_replace_pointer(cs->slots[!idx], new, + lockdep_is_held(&cs->lock)); + break; + } + spin_unlock_bh(&cs->lock); + + if (old) + ovpn_crypto_key_slot_put(old); + + return 0; +} + +void ovpn_crypto_key_slot_delete(struct ovpn_crypto_state *cs, + enum ovpn_key_slot slot) +{ + struct ovpn_crypto_key_slot *ks = NULL; + u8 idx; + + if (slot != OVPN_KEY_SLOT_PRIMARY && + slot != OVPN_KEY_SLOT_SECONDARY) { + pr_warn("Invalid slot to release: %u\n", slot); + return; + } + + spin_lock_bh(&cs->lock); + idx = cs->primary_idx; + switch (slot) { + case OVPN_KEY_SLOT_PRIMARY: + ks = rcu_replace_pointer(cs->slots[idx], NULL, + lockdep_is_held(&cs->lock)); + break; + case OVPN_KEY_SLOT_SECONDARY: + ks = rcu_replace_pointer(cs->slots[!idx], NULL, + lockdep_is_held(&cs->lock)); + break; + } + spin_unlock_bh(&cs->lock); + + if (!ks) { + pr_debug("Key slot already released: %u\n", slot); + return; + } + + pr_debug("deleting key slot %u, key_id=%u\n", slot, ks->key_id); + ovpn_crypto_key_slot_put(ks); +} + +/* this swap is not atomic, but there will be a very short time frame where the + * old_secondary key won't be available. This should not be a big deal as most + * likely both peers are already using the new primary at this point. + */ +void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs) +{ + const struct ovpn_crypto_key_slot *old_primary, *old_secondary; + u8 idx; + + spin_lock_bh(&cs->lock); + idx = cs->primary_idx; + old_primary = rcu_dereference_protected(cs->slots[idx], + lockdep_is_held(&cs->lock)); + old_secondary = rcu_dereference_protected(cs->slots[!idx], + lockdep_is_held(&cs->lock)); + /* perform real swap by switching the index of the primary key */ + cs->primary_idx = !cs->primary_idx; + + pr_debug("key swapped: (old primary) %d <-> (new primary) %d\n", + old_primary ? old_primary->key_id : -1, + old_secondary ? old_secondary->key_id : -1); + + spin_unlock_bh(&cs->lock); +} diff --git a/drivers/net/ovpn/crypto.h b/drivers/net/ovpn/crypto.h new file mode 100644 index 0000000000000000000000000000000000000000..b1b77c38ffe68dc21079e3a5354cc0695caa9cf3 --- /dev/null +++ b/drivers/net/ovpn/crypto.h @@ -0,0 +1,139 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_OVPNCRYPTO_H_ +#define _NET_OVPN_OVPNCRYPTO_H_ + +#include "pktid.h" +#include "proto.h" + +/* info needed for both encrypt and decrypt directions */ +struct ovpn_key_direction { + const u8 *cipher_key; + size_t cipher_key_size; + const u8 *nonce_tail; /* only needed for GCM modes */ + size_t nonce_tail_size; /* only needed for GCM modes */ +}; + +/* all info for a particular symmetric key (primary or secondary) */ +struct ovpn_key_config { + enum ovpn_cipher_alg cipher_alg; + u8 key_id; + struct ovpn_key_direction encrypt; + struct ovpn_key_direction decrypt; +}; + +/* used to pass settings from netlink to the crypto engine */ +struct ovpn_peer_key_reset { + enum ovpn_key_slot slot; + struct ovpn_key_config key; +}; + +struct ovpn_crypto_key_slot { + u8 key_id; + + struct crypto_aead *encrypt; + struct crypto_aead *decrypt; + u8 nonce_tail_xmit[OVPN_NONCE_TAIL_SIZE]; + u8 nonce_tail_recv[OVPN_NONCE_TAIL_SIZE]; + + struct ovpn_pktid_recv pid_recv ____cacheline_aligned_in_smp; + struct ovpn_pktid_xmit pid_xmit ____cacheline_aligned_in_smp; + struct kref refcount; + struct rcu_head rcu; +}; + +struct ovpn_crypto_state { + struct ovpn_crypto_key_slot __rcu *slots[2]; + u8 primary_idx; + + /* protects primary and secondary slots */ + spinlock_t lock; +}; + +static inline bool ovpn_crypto_key_slot_hold(struct ovpn_crypto_key_slot *ks) +{ + return kref_get_unless_zero(&ks->refcount); +} + +static inline void ovpn_crypto_state_init(struct ovpn_crypto_state *cs) +{ + RCU_INIT_POINTER(cs->slots[0], NULL); + RCU_INIT_POINTER(cs->slots[1], NULL); + cs->primary_idx = 0; + spin_lock_init(&cs->lock); +} + +static inline struct ovpn_crypto_key_slot * +ovpn_crypto_key_id_to_slot(const struct ovpn_crypto_state *cs, u8 key_id) +{ + struct ovpn_crypto_key_slot *ks; + u8 idx; + + if (unlikely(!cs)) + return NULL; + + rcu_read_lock(); + idx = cs->primary_idx; + ks = rcu_dereference(cs->slots[idx]); + if (ks && ks->key_id == key_id) { + if (unlikely(!ovpn_crypto_key_slot_hold(ks))) + ks = NULL; + goto out; + } + + ks = rcu_dereference(cs->slots[idx ^ 1]); + if (ks && ks->key_id == key_id) { + if (unlikely(!ovpn_crypto_key_slot_hold(ks))) + ks = NULL; + goto out; + } + + /* when both key slots are occupied but no matching key ID is found, ks + * has to be reset to NULL to avoid carrying a stale pointer + */ + ks = NULL; +out: + rcu_read_unlock(); + + return ks; +} + +static inline struct ovpn_crypto_key_slot * +ovpn_crypto_key_slot_primary(const struct ovpn_crypto_state *cs) +{ + struct ovpn_crypto_key_slot *ks; + + rcu_read_lock(); + ks = rcu_dereference(cs->slots[cs->primary_idx]); + if (unlikely(ks && !ovpn_crypto_key_slot_hold(ks))) + ks = NULL; + rcu_read_unlock(); + + return ks; +} + +void ovpn_crypto_key_slot_release(struct kref *kref); + +static inline void ovpn_crypto_key_slot_put(struct ovpn_crypto_key_slot *ks) +{ + kref_put(&ks->refcount, ovpn_crypto_key_slot_release); +} + +int ovpn_crypto_state_reset(struct ovpn_crypto_state *cs, + const struct ovpn_peer_key_reset *pkr); + +void ovpn_crypto_key_slot_delete(struct ovpn_crypto_state *cs, + enum ovpn_key_slot slot); + +void ovpn_crypto_state_release(struct ovpn_crypto_state *cs); + +void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs); + +#endif /* _NET_OVPN_OVPNCRYPTO_H_ */ diff --git a/drivers/net/ovpn/crypto_aead.c b/drivers/net/ovpn/crypto_aead.c new file mode 100644 index 0000000000000000000000000000000000000000..dade83aad09b2d79ad65152ce867a961aeec01bd --- /dev/null +++ b/drivers/net/ovpn/crypto_aead.c @@ -0,0 +1,366 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#include <crypto/aead.h> +#include <linux/skbuff.h> +#include <net/ip.h> +#include <net/ipv6.h> +#include <net/udp.h> + +#include "ovpnstruct.h" +#include "main.h" +#include "io.h" +#include "pktid.h" +#include "crypto_aead.h" +#include "crypto.h" +#include "peer.h" +#include "proto.h" +#include "skb.h" + +#define AUTH_TAG_SIZE 16 + +#define ALG_NAME_AES "gcm(aes)" +#define ALG_NAME_CHACHAPOLY "rfc7539(chacha20,poly1305)" + +static int ovpn_aead_encap_overhead(const struct ovpn_crypto_key_slot *ks) +{ + return OVPN_OPCODE_SIZE + /* OP header size */ + sizeof(u32) + /* Packet ID */ + crypto_aead_authsize(ks->encrypt); /* Auth Tag */ +} + +int ovpn_aead_encrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks, + struct sk_buff *skb) +{ + const unsigned int tag_size = crypto_aead_authsize(ks->encrypt); + struct aead_request *req; + struct sk_buff *trailer; + struct scatterlist *sg; + u8 iv[OVPN_NONCE_SIZE]; + int nfrags, ret; + u32 pktid, op; + + ovpn_skb_cb(skb)->peer = peer; + ovpn_skb_cb(skb)->ks = ks; + + /* Sample AEAD header format: + * 48000001 00000005 7e7046bd 444a7e28 cc6387b1 64a4d6c1 380275a... + * [ OP32 ] [seq # ] [ auth tag ] [ payload ... ] + * [4-byte + * IV head] + */ + + /* check that there's enough headroom in the skb for packet + * encapsulation + */ + if (unlikely(skb_cow_head(skb, OVPN_HEAD_ROOM))) + return -ENOBUFS; + + /* get number of skb frags and ensure that packet data is writable */ + nfrags = skb_cow_data(skb, 0, &trailer); + if (unlikely(nfrags < 0)) + return nfrags; + + if (unlikely(nfrags + 2 > (MAX_SKB_FRAGS + 2))) + return -ENOSPC; + + ovpn_skb_cb(skb)->sg = kmalloc(sizeof(*ovpn_skb_cb(skb)->sg) * + (nfrags + 2), GFP_ATOMIC); + if (unlikely(!ovpn_skb_cb(skb)->sg)) + return -ENOMEM; + + sg = ovpn_skb_cb(skb)->sg; + + /* sg table: + * 0: op, wire nonce (AD, len=OVPN_OP_SIZE_V2+OVPN_NONCE_WIRE_SIZE), + * 1, 2, 3, ..., n: payload, + * n+1: auth_tag (len=tag_size) + */ + sg_init_table(sg, nfrags + 2); + + /* build scatterlist to encrypt packet payload */ + ret = skb_to_sgvec_nomark(skb, sg + 1, 0, skb->len); + if (unlikely(nfrags != ret)) { + ret = -EINVAL; + goto free_sg; + } + + /* append auth_tag onto scatterlist */ + __skb_push(skb, tag_size); + sg_set_buf(sg + nfrags + 1, skb->data, tag_size); + + /* obtain packet ID, which is used both as a first + * 4 bytes of nonce and last 4 bytes of associated data. + */ + ret = ovpn_pktid_xmit_next(&ks->pid_xmit, &pktid); + if (unlikely(ret < 0)) + goto free_sg; + + /* concat 4 bytes packet id and 8 bytes nonce tail into 12 bytes + * nonce + */ + ovpn_pktid_aead_write(pktid, ks->nonce_tail_xmit, iv); + + /* make space for packet id and push it to the front */ + __skb_push(skb, OVPN_NONCE_WIRE_SIZE); + memcpy(skb->data, iv, OVPN_NONCE_WIRE_SIZE); + + /* add packet op as head of additional data */ + op = ovpn_opcode_compose(OVPN_DATA_V2, ks->key_id, peer->id); + __skb_push(skb, OVPN_OPCODE_SIZE); + BUILD_BUG_ON(sizeof(op) != OVPN_OPCODE_SIZE); + *((__force __be32 *)skb->data) = htonl(op); + + /* AEAD Additional data */ + sg_set_buf(sg, skb->data, OVPN_OPCODE_SIZE + OVPN_NONCE_WIRE_SIZE); + + req = aead_request_alloc(ks->encrypt, GFP_ATOMIC); + if (unlikely(!req)) { + ret = -ENOMEM; + goto free_sg; + } + + ovpn_skb_cb(skb)->req = req; + + /* setup async crypto operation */ + aead_request_set_tfm(req, ks->encrypt); + aead_request_set_callback(req, 0, ovpn_encrypt_post, skb); + aead_request_set_crypt(req, sg, sg, + skb->len - ovpn_aead_encap_overhead(ks), iv); + aead_request_set_ad(req, OVPN_OPCODE_SIZE + OVPN_NONCE_WIRE_SIZE); + + /* encrypt it */ + return crypto_aead_encrypt(req); +free_sg: + kfree(ovpn_skb_cb(skb)->sg); + ovpn_skb_cb(skb)->sg = NULL; + return ret; +} + +int ovpn_aead_decrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks, + struct sk_buff *skb) +{ + const unsigned int tag_size = crypto_aead_authsize(ks->decrypt); + int ret, payload_len, nfrags; + unsigned int payload_offset; + struct aead_request *req; + struct sk_buff *trailer; + struct scatterlist *sg; + u8 iv[OVPN_NONCE_SIZE]; + unsigned int sg_len; + + payload_offset = OVPN_OPCODE_SIZE + OVPN_NONCE_WIRE_SIZE + tag_size; + payload_len = skb->len - payload_offset; + + ovpn_skb_cb(skb)->payload_offset = payload_offset; + ovpn_skb_cb(skb)->peer = peer; + ovpn_skb_cb(skb)->ks = ks; + + /* sanity check on packet size, payload size must be >= 0 */ + if (unlikely(payload_len < 0)) + return -EINVAL; + + /* Prepare the skb data buffer to be accessed up until the auth tag. + * This is required because this area is directly mapped into the sg + * list. + */ + if (unlikely(!pskb_may_pull(skb, payload_offset))) + return -ENODATA; + + /* get number of skb frags and ensure that packet data is writable */ + nfrags = skb_cow_data(skb, 0, &trailer); + if (unlikely(nfrags < 0)) + return nfrags; + + if (unlikely(nfrags + 2 > (MAX_SKB_FRAGS + 2))) + return -ENOSPC; + + ovpn_skb_cb(skb)->sg = kmalloc(sizeof(*ovpn_skb_cb(skb)->sg) * + (nfrags + 2), GFP_ATOMIC); + if (unlikely(!ovpn_skb_cb(skb)->sg)) + return -ENOMEM; + + sg = ovpn_skb_cb(skb)->sg; + + /* sg table: + * 0: op, wire nonce (AD, len=OVPN_OPCODE_SIZE+OVPN_NONCE_WIRE_SIZE), + * 1, 2, 3, ..., n: payload, + * n+1: auth_tag (len=tag_size) + */ + sg_init_table(sg, nfrags + 2); + + /* packet op is head of additional data */ + sg_len = OVPN_OPCODE_SIZE + OVPN_NONCE_WIRE_SIZE; + sg_set_buf(sg, skb->data, sg_len); + + /* build scatterlist to decrypt packet payload */ + ret = skb_to_sgvec_nomark(skb, sg + 1, payload_offset, payload_len); + if (unlikely(nfrags != ret)) { + ret = -EINVAL; + goto free_sg; + } + + /* append auth_tag onto scatterlist */ + sg_set_buf(sg + nfrags + 1, skb->data + sg_len, tag_size); + + /* copy nonce into IV buffer */ + memcpy(iv, skb->data + OVPN_OPCODE_SIZE, OVPN_NONCE_WIRE_SIZE); + memcpy(iv + OVPN_NONCE_WIRE_SIZE, ks->nonce_tail_recv, + OVPN_NONCE_TAIL_SIZE); + + req = aead_request_alloc(ks->decrypt, GFP_ATOMIC); + if (unlikely(!req)) { + ret = -ENOMEM; + goto free_sg; + } + + ovpn_skb_cb(skb)->req = req; + + /* setup async crypto operation */ + aead_request_set_tfm(req, ks->decrypt); + aead_request_set_callback(req, 0, ovpn_decrypt_post, skb); + aead_request_set_crypt(req, sg, sg, payload_len + tag_size, iv); + + aead_request_set_ad(req, OVPN_NONCE_WIRE_SIZE + OVPN_OPCODE_SIZE); + + /* decrypt it */ + return crypto_aead_decrypt(req); +free_sg: + kfree(ovpn_skb_cb(skb)->sg); + ovpn_skb_cb(skb)->sg = NULL; + return ret; +} + +/* Initialize a struct crypto_aead object */ +struct crypto_aead *ovpn_aead_init(const char *title, const char *alg_name, + const unsigned char *key, + unsigned int keylen) +{ + struct crypto_aead *aead; + int ret; + + aead = crypto_alloc_aead(alg_name, 0, 0); + if (IS_ERR(aead)) { + ret = PTR_ERR(aead); + pr_err("%s crypto_alloc_aead failed, err=%d\n", title, ret); + aead = NULL; + goto error; + } + + ret = crypto_aead_setkey(aead, key, keylen); + if (ret) { + pr_err("%s crypto_aead_setkey size=%u failed, err=%d\n", title, + keylen, ret); + goto error; + } + + ret = crypto_aead_setauthsize(aead, AUTH_TAG_SIZE); + if (ret) { + pr_err("%s crypto_aead_setauthsize failed, err=%d\n", title, + ret); + goto error; + } + + /* basic AEAD assumption */ + if (crypto_aead_ivsize(aead) != OVPN_NONCE_SIZE) { + pr_err("%s IV size must be %d\n", title, OVPN_NONCE_SIZE); + ret = -EINVAL; + goto error; + } + + pr_debug("********* Cipher %s (%s)\n", alg_name, title); + pr_debug("*** IV size=%u\n", crypto_aead_ivsize(aead)); + pr_debug("*** req size=%u\n", crypto_aead_reqsize(aead)); + pr_debug("*** block size=%u\n", crypto_aead_blocksize(aead)); + pr_debug("*** auth size=%u\n", crypto_aead_authsize(aead)); + pr_debug("*** alignmask=0x%x\n", crypto_aead_alignmask(aead)); + + return aead; + +error: + crypto_free_aead(aead); + return ERR_PTR(ret); +} + +void ovpn_aead_crypto_key_slot_destroy(struct ovpn_crypto_key_slot *ks) +{ + if (!ks) + return; + + crypto_free_aead(ks->encrypt); + crypto_free_aead(ks->decrypt); + kfree(ks); +} + +struct ovpn_crypto_key_slot * +ovpn_aead_crypto_key_slot_new(const struct ovpn_key_config *kc) +{ + struct ovpn_crypto_key_slot *ks = NULL; + const char *alg_name; + int ret; + + /* validate crypto alg */ + switch (kc->cipher_alg) { + case OVPN_CIPHER_ALG_AES_GCM: + alg_name = ALG_NAME_AES; + break; + case OVPN_CIPHER_ALG_CHACHA20_POLY1305: + alg_name = ALG_NAME_CHACHAPOLY; + break; + default: + return ERR_PTR(-EOPNOTSUPP); + } + + if (kc->encrypt.nonce_tail_size != OVPN_NONCE_TAIL_SIZE || + kc->decrypt.nonce_tail_size != OVPN_NONCE_TAIL_SIZE) + return ERR_PTR(-EINVAL); + + /* build the key slot */ + ks = kmalloc(sizeof(*ks), GFP_KERNEL); + if (!ks) + return ERR_PTR(-ENOMEM); + + ks->encrypt = NULL; + ks->decrypt = NULL; + kref_init(&ks->refcount); + ks->key_id = kc->key_id; + + ks->encrypt = ovpn_aead_init("encrypt", alg_name, + kc->encrypt.cipher_key, + kc->encrypt.cipher_key_size); + if (IS_ERR(ks->encrypt)) { + ret = PTR_ERR(ks->encrypt); + ks->encrypt = NULL; + goto destroy_ks; + } + + ks->decrypt = ovpn_aead_init("decrypt", alg_name, + kc->decrypt.cipher_key, + kc->decrypt.cipher_key_size); + if (IS_ERR(ks->decrypt)) { + ret = PTR_ERR(ks->decrypt); + ks->decrypt = NULL; + goto destroy_ks; + } + + memcpy(ks->nonce_tail_xmit, kc->encrypt.nonce_tail, + OVPN_NONCE_TAIL_SIZE); + memcpy(ks->nonce_tail_recv, kc->decrypt.nonce_tail, + OVPN_NONCE_TAIL_SIZE); + + /* init packet ID generation/validation */ + ovpn_pktid_xmit_init(&ks->pid_xmit); + ovpn_pktid_recv_init(&ks->pid_recv); + + return ks; + +destroy_ks: + ovpn_aead_crypto_key_slot_destroy(ks); + return ERR_PTR(ret); +} diff --git a/drivers/net/ovpn/crypto_aead.h b/drivers/net/ovpn/crypto_aead.h new file mode 100644 index 0000000000000000000000000000000000000000..77ee8141599bc06b0dc664c5b0a4dae660a89238 --- /dev/null +++ b/drivers/net/ovpn/crypto_aead.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_OVPNAEAD_H_ +#define _NET_OVPN_OVPNAEAD_H_ + +#include "crypto.h" + +#include <asm/types.h> +#include <linux/skbuff.h> + +struct crypto_aead *ovpn_aead_init(const char *title, const char *alg_name, + const unsigned char *key, + unsigned int keylen); + +int ovpn_aead_encrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks, + struct sk_buff *skb); +int ovpn_aead_decrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks, + struct sk_buff *skb); + +struct ovpn_crypto_key_slot * +ovpn_aead_crypto_key_slot_new(const struct ovpn_key_config *kc); +void ovpn_aead_crypto_key_slot_destroy(struct ovpn_crypto_key_slot *ks); + +#endif /* _NET_OVPN_OVPNAEAD_H_ */ diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 9f5c6b06c79681048f750fce89e9683da41ea642..124292a49cd251a3b5021dc8828813941c187e54 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -7,6 +7,7 @@ * Antonio Quartulli antonio@openvpn.net */

+#include <crypto/aead.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <net/gro_cells.h> @@ -15,6 +16,9 @@ #include "ovpnstruct.h" #include "peer.h" #include "io.h" +#include "bind.h" +#include "crypto.h" +#include "crypto_aead.h" #include "netlink.h" #include "proto.h" #include "udp.h" @@ -44,7 +48,7 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb) skb_set_queue_mapping(skb, 0); skb_scrub_packet(skb, true);

- skb_reset_network_header(skb); + /* network header reset in ovpn_decrypt_post() */ skb_reset_transport_header(skb); skb_reset_inner_headers(skb);

@@ -56,33 +60,140 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb) dev_sw_netstats_rx_add(peer->ovpn->dev, pkt_len); }

-static void ovpn_decrypt_post(struct sk_buff *skb, int ret) +void ovpn_decrypt_post(void *data, int ret) { - struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer; + struct ovpn_crypto_key_slot *ks; + unsigned int payload_offset = 0; + struct sk_buff *skb = data; + struct ovpn_peer *peer; + __be16 proto; + __be32 *pid; + + /* crypto is happening asynchronously. this function will be called + * again later by the crypto callback with a proper return code + */ + if (unlikely(ret == -EINPROGRESS)) + return; + + payload_offset = ovpn_skb_cb(skb)->payload_offset; + ks = ovpn_skb_cb(skb)->ks; + peer = ovpn_skb_cb(skb)->peer; + + /* crypto is done, cleanup skb CB and its members */ + + if (likely(ovpn_skb_cb(skb)->sg)) + kfree(ovpn_skb_cb(skb)->sg); + + if (likely(ovpn_skb_cb(skb)->req)) + aead_request_free(ovpn_skb_cb(skb)->req);

if (unlikely(ret < 0)) goto drop;

+ /* PID sits after the op */ + pid = (__force __be32 *)(skb->data + OVPN_OPCODE_SIZE); + ret = ovpn_pktid_recv(&ks->pid_recv, ntohl(*pid), 0); + if (unlikely(ret < 0)) { + net_err_ratelimited("%s: PKT ID RX error for peer %u: %d\n", + netdev_name(peer->ovpn->dev), peer->id, + ret); + goto drop; + } + + /* point to encapsulated IP packet */ + __skb_pull(skb, payload_offset); + + /* check if this is a valid datapacket that has to be delivered to the + * ovpn interface + */ + skb_reset_network_header(skb); + proto = ovpn_ip_check_protocol(skb); + if (unlikely(!proto)) { + /* check if null packet */ + if (unlikely(!pskb_may_pull(skb, 1))) { + net_info_ratelimited("%s: NULL packet received from peer %u\n", + netdev_name(peer->ovpn->dev), + peer->id); + goto drop; + } + + net_info_ratelimited("%s: unsupported protocol received from peer %u\n", + netdev_name(peer->ovpn->dev), peer->id); + goto drop; + } + skb->protocol = proto; + + /* perform Reverse Path Filtering (RPF) */ + if (unlikely(!ovpn_peer_check_by_src(peer->ovpn, skb, peer))) { + if (skb->protocol == htons(ETH_P_IPV6)) + net_dbg_ratelimited("%s: RPF dropped packet from peer %u, src: %pI6c\n", + netdev_name(peer->ovpn->dev), + peer->id, &ipv6_hdr(skb)->saddr); + else + net_dbg_ratelimited("%s: RPF dropped packet from peer %u, src: %pI4\n", + netdev_name(peer->ovpn->dev), + peer->id, &ip_hdr(skb)->saddr); + goto drop; + } + ovpn_netdev_write(peer, skb); /* skb is passed to upper layer - don't free it */ skb = NULL; drop: if (unlikely(skb)) dev_core_stats_rx_dropped_inc(peer->ovpn->dev); - ovpn_peer_put(peer); + if (likely(peer)) + ovpn_peer_put(peer); + if (likely(ks)) + ovpn_crypto_key_slot_put(ks); kfree_skb(skb); }

/* RX path entry point: decrypt packet and forward it to the device */ void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb) { - ovpn_skb_cb(skb)->peer = peer; - ovpn_decrypt_post(skb, 0); + struct ovpn_crypto_key_slot *ks; + u8 key_id; + + /* get the key slot matching the key ID in the received packet */ + key_id = ovpn_key_id_from_skb(skb); + ks = ovpn_crypto_key_id_to_slot(&peer->crypto, key_id); + if (unlikely(!ks)) { + net_info_ratelimited("%s: no available key for peer %u, key-id: %u\n", + netdev_name(peer->ovpn->dev), peer->id, + key_id); + dev_core_stats_rx_dropped_inc(peer->ovpn->dev); + kfree_skb(skb); + ovpn_peer_put(peer); + return; + } + + memset(ovpn_skb_cb(skb), 0, sizeof(struct ovpn_cb)); + ovpn_decrypt_post(skb, ovpn_aead_decrypt(peer, ks, skb)); }

-static void ovpn_encrypt_post(struct sk_buff *skb, int ret) +void ovpn_encrypt_post(void *data, int ret) { - struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer; + struct ovpn_crypto_key_slot *ks; + struct sk_buff *skb = data; + struct ovpn_peer *peer; + + /* encryption is happening asynchronously. This function will be + * called later by the crypto callback with a proper return value + */ + if (unlikely(ret == -EINPROGRESS)) + return; + + ks = ovpn_skb_cb(skb)->ks; + peer = ovpn_skb_cb(skb)->peer; + + /* crypto is done, cleanup skb CB and its members */ + + if (likely(ovpn_skb_cb(skb)->sg)) + kfree(ovpn_skb_cb(skb)->sg); + + if (likely(ovpn_skb_cb(skb)->req)) + aead_request_free(ovpn_skb_cb(skb)->req);

if (unlikely(ret < 0)) goto err; @@ -102,13 +213,28 @@ static void ovpn_encrypt_post(struct sk_buff *skb, int ret) err: if (unlikely(skb)) dev_core_stats_tx_dropped_inc(peer->ovpn->dev); - ovpn_peer_put(peer); + if (likely(peer)) + ovpn_peer_put(peer); + if (likely(ks)) + ovpn_crypto_key_slot_put(ks); kfree_skb(skb); }

static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb) { - ovpn_skb_cb(skb)->peer = peer; + struct ovpn_crypto_key_slot *ks; + + if (unlikely(skb->ip_summed == CHECKSUM_PARTIAL && + skb_checksum_help(skb))) { + net_warn_ratelimited("%s: cannot compute checksum for outgoing packet for peer %u\n", + netdev_name(peer->ovpn->dev), peer->id); + return false; + } + + /* get primary key to be used for encrypting data */ + ks = ovpn_crypto_key_slot_primary(&peer->crypto); + if (unlikely(!ks)) + return false;

/* take a reference to the peer because the crypto code may run async. * ovpn_encrypt_post() will release it upon completion @@ -118,7 +244,8 @@ static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb) return false; }

- ovpn_encrypt_post(skb, 0); + memset(ovpn_skb_cb(skb), 0, sizeof(struct ovpn_cb)); + ovpn_encrypt_post(skb, ovpn_aead_encrypt(peer, ks, skb)); return true; }

diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h index b3830b787e16f3bdcaaff94e5bbe89be3e1006fe..5f9c7eba37b132bcf8c0ebad60af9171e46bf3e8 100644 --- a/drivers/net/ovpn/io.h +++ b/drivers/net/ovpn/io.h @@ -23,4 +23,7 @@ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev);

void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb);

+void ovpn_encrypt_post(void *data, int ret); +void ovpn_decrypt_post(void *data, int ret); + #endif /* _NET_OVPN_OVPN_H_ */ diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index d89c82aae2c7646f8c40cdde5bfe364c8b46c659..456fd70ccd2a7e37f0ad1732ca9f5a07f2f54a97 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -12,6 +12,8 @@

#include "ovpnstruct.h" #include "bind.h" +#include "pktid.h" +#include "crypto.h" #include "io.h" #include "main.h" #include "netlink.h" @@ -42,6 +44,7 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id) peer->vpn_addrs.ipv6 = in6addr_any;

RCU_INIT_POINTER(peer->bind, NULL); + ovpn_crypto_state_init(&peer->crypto); spin_lock_init(&peer->lock); kref_init(&peer->refcount);

@@ -80,7 +83,10 @@ static void ovpn_peer_release_rcu(struct rcu_head *head) */ static void ovpn_peer_release(struct ovpn_peer *peer) { + ovpn_crypto_state_release(&peer->crypto); + spin_lock_bh(&peer->lock); ovpn_bind_reset(peer, NULL); + spin_unlock_bh(&peer->lock); netdev_put(peer->ovpn->dev, &peer->ovpn->dev_tracker); call_rcu(&peer->rcu, ovpn_peer_release_rcu); } @@ -286,6 +292,29 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn, return peer; }

+/** + * ovpn_peer_check_by_src - check that skb source is routed via peer + * @ovpn: the openvpn instance to search + * @skb: the packet to extract source address from + * @peer: the peer to check against the source address + * + * Return: true if the peer is matching or false otherwise + */ +bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb, + struct ovpn_peer *peer) +{ + bool match = false; + + if (ovpn->mode == OVPN_MODE_P2P) { + /* in P2P mode, no matter the destination, packets are always + * sent to the single peer listening on the other side + */ + match = (peer == rcu_access_pointer(ovpn->peer)); + } + + return match; +} + /** * ovpn_peer_add_p2p - add peer to related tables in a P2P instance * @ovpn: the instance to add the peer to diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 24de7a69e371a521bed48a8ef3116350ea3e9560..1b427870df2cf972e0f572e046452378358f245a 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -12,6 +12,8 @@

#include <net/dst_cache.h>

+#include "crypto.h" + /** * struct ovpn_peer - the main remote peer object * @ovpn: main openvpn instance this peer belongs to @@ -20,6 +22,7 @@ * @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel * @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel * @sock: the socket being used to talk to this peer + * @crypto: the crypto configuration (ciphers, keys, etc..) * @dst_cache: cache for dst_entry used to send to peer * @bind: remote peer binding * @delete_reason: why peer was deleted (i.e. timeout, transport error, ..) @@ -36,6 +39,7 @@ struct ovpn_peer { struct in6_addr ipv6; } vpn_addrs; struct ovpn_socket *sock; + struct ovpn_crypto_state crypto; struct dst_cache dst_cache; struct ovpn_bind __rcu *bind; enum ovpn_del_peer_reason delete_reason; @@ -78,5 +82,7 @@ struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn, struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id); struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn, struct sk_buff *skb); +bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb, + struct ovpn_peer *peer);

#endif /* _NET_OVPN_OVPNPEER_H_ */ diff --git a/drivers/net/ovpn/pktid.c b/drivers/net/ovpn/pktid.c new file mode 100644 index 0000000000000000000000000000000000000000..0707a0489863d710fee05915007e4747f5bb4fa5 --- /dev/null +++ b/drivers/net/ovpn/pktid.c @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + * James Yonan james@openvpn.net + */ + +#include <linux/atomic.h> +#include <linux/jiffies.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/types.h> + +#include "ovpnstruct.h" +#include "main.h" +#include "pktid.h" + +void ovpn_pktid_xmit_init(struct ovpn_pktid_xmit *pid) +{ + atomic64_set(&pid->seq_num, 1); +} + +void ovpn_pktid_recv_init(struct ovpn_pktid_recv *pr) +{ + memset(pr, 0, sizeof(*pr)); + spin_lock_init(&pr->lock); +} + +/* Packet replay detection. + * Allows ID backtrack of up to REPLAY_WINDOW_SIZE - 1. + */ +int ovpn_pktid_recv(struct ovpn_pktid_recv *pr, u32 pkt_id, u32 pkt_time) +{ + const unsigned long now = jiffies; + int ret; + + /* ID must not be zero */ + if (unlikely(pkt_id == 0)) + return -EINVAL; + + spin_lock_bh(&pr->lock); + + /* expire backtracks at or below pr->id after PKTID_RECV_EXPIRE time */ + if (unlikely(time_after_eq(now, pr->expire))) + pr->id_floor = pr->id; + + /* time changed? */ + if (unlikely(pkt_time != pr->time)) { + if (pkt_time > pr->time) { + /* time moved forward, accept */ + pr->base = 0; + pr->extent = 0; + pr->id = 0; + pr->time = pkt_time; + pr->id_floor = 0; + } else { + /* time moved backward, reject */ + ret = -ETIME; + goto out; + } + } + + if (likely(pkt_id == pr->id + 1)) { + /* well-formed ID sequence (incremented by 1) */ + pr->base = REPLAY_INDEX(pr->base, -1); + pr->history[pr->base / 8] |= (1 << (pr->base % 8)); + if (pr->extent < REPLAY_WINDOW_SIZE) + ++pr->extent; + pr->id = pkt_id; + } else if (pkt_id > pr->id) { + /* ID jumped forward by more than one */ + const unsigned int delta = pkt_id - pr->id; + + if (delta < REPLAY_WINDOW_SIZE) { + unsigned int i; + + pr->base = REPLAY_INDEX(pr->base, -delta); + pr->history[pr->base / 8] |= (1 << (pr->base % 8)); + pr->extent += delta; + if (pr->extent > REPLAY_WINDOW_SIZE) + pr->extent = REPLAY_WINDOW_SIZE; + for (i = 1; i < delta; ++i) { + unsigned int newb = REPLAY_INDEX(pr->base, i); + + pr->history[newb / 8] &= ~BIT(newb % 8); + } + } else { + pr->base = 0; + pr->extent = REPLAY_WINDOW_SIZE; + memset(pr->history, 0, sizeof(pr->history)); + pr->history[0] = 1; + } + pr->id = pkt_id; + } else { + /* ID backtrack */ + const unsigned int delta = pr->id - pkt_id; + + if (delta > pr->max_backtrack) + pr->max_backtrack = delta; + if (delta < pr->extent) { + if (pkt_id > pr->id_floor) { + const unsigned int ri = REPLAY_INDEX(pr->base, + delta); + u8 *p = &pr->history[ri / 8]; + const u8 mask = (1 << (ri % 8)); + + if (*p & mask) { + ret = -EINVAL; + goto out; + } + *p |= mask; + } else { + ret = -EINVAL; + goto out; + } + } else { + ret = -EINVAL; + goto out; + } + } + + pr->expire = now + PKTID_RECV_EXPIRE; + ret = 0; +out: + spin_unlock_bh(&pr->lock); + return ret; +} diff --git a/drivers/net/ovpn/pktid.h b/drivers/net/ovpn/pktid.h new file mode 100644 index 0000000000000000000000000000000000000000..ab38c59b6174074b8deb23e3e9ce47e96016ba94 --- /dev/null +++ b/drivers/net/ovpn/pktid.h @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + * James Yonan james@openvpn.net + */ + +#ifndef _NET_OVPN_OVPNPKTID_H_ +#define _NET_OVPN_OVPNPKTID_H_ + +#include "proto.h" + +/* If no packets received for this length of time, set a backtrack floor + * at highest received packet ID thus far. + */ +#define PKTID_RECV_EXPIRE (30 * HZ) + +/* Packet-ID state for transmitter */ +struct ovpn_pktid_xmit { + atomic64_t seq_num; +}; + +/* replay window sizing in bytes = 2^REPLAY_WINDOW_ORDER */ +#define REPLAY_WINDOW_ORDER 8 + +#define REPLAY_WINDOW_BYTES BIT(REPLAY_WINDOW_ORDER) +#define REPLAY_WINDOW_SIZE (REPLAY_WINDOW_BYTES * 8) +#define REPLAY_INDEX(base, i) (((base) + (i)) & (REPLAY_WINDOW_SIZE - 1)) + +/* Packet-ID state for receiver. + * Other than lock member, can be zeroed to initialize. + */ +struct ovpn_pktid_recv { + /* "sliding window" bitmask of recent packet IDs received */ + u8 history[REPLAY_WINDOW_BYTES]; + /* bit position of deque base in history */ + unsigned int base; + /* extent (in bits) of deque in history */ + unsigned int extent; + /* expiration of history in jiffies */ + unsigned long expire; + /* highest sequence number received */ + u32 id; + /* highest time stamp received */ + u32 time; + /* we will only accept backtrack IDs > id_floor */ + u32 id_floor; + unsigned int max_backtrack; + /* protects entire pktd ID state */ + spinlock_t lock; +}; + +/* Get the next packet ID for xmit */ +static inline int ovpn_pktid_xmit_next(struct ovpn_pktid_xmit *pid, u32 *pktid) +{ + const s64 seq_num = atomic64_fetch_add_unless(&pid->seq_num, 1, + 0x100000000LL); + /* when the 32bit space is over, we return an error because the packet + * ID is used to create the cipher IV and we do not want to reuse the + * same value more than once + */ + if (unlikely(seq_num == 0x100000000LL)) + return -ERANGE; + + *pktid = (u32)seq_num; + + return 0; +} + +/* Write 12-byte AEAD IV to dest */ +static inline void ovpn_pktid_aead_write(const u32 pktid, + const u8 nt[], + unsigned char *dest) +{ + *(__force __be32 *)(dest) = htonl(pktid); + BUILD_BUG_ON(4 + OVPN_NONCE_TAIL_SIZE != OVPN_NONCE_SIZE); + memcpy(dest + 4, nt, OVPN_NONCE_TAIL_SIZE); +} + +void ovpn_pktid_xmit_init(struct ovpn_pktid_xmit *pid); +void ovpn_pktid_recv_init(struct ovpn_pktid_recv *pr); + +int ovpn_pktid_recv(struct ovpn_pktid_recv *pr, u32 pkt_id, u32 pkt_time); + +#endif /* _NET_OVPN_OVPNPKTID_H_ */ diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h index 34a812869b2e92e8bab0ebb87d46b67c3bbccf9f..9809e6cf752db4722659d201d58f221d83def2b8 100644 --- a/drivers/net/ovpn/proto.h +++ b/drivers/net/ovpn/proto.h @@ -83,4 +83,36 @@ static inline u32 ovpn_peer_id_from_skb(const struct sk_buff *skb, u16 offset) return FIELD_GET(OVPN_OPCODE_PEERID_MASK, opcode); }

+/** + * ovpn_key_id_from_skb - extract key ID from the skb head + * @skb: the packet to extract the key ID code from + * + * Note: this function assumes that the skb head was pulled enough + * to access the first byte. + * + * Return: the key ID + */ +static inline u8 ovpn_key_id_from_skb(const struct sk_buff *skb) +{ + u32 opcode = be32_to_cpu(*(__be32 *)skb->data); + + return FIELD_GET(OVPN_OPCODE_KEYID_MASK, opcode); +} + +/** + * ovpn_opcode_compose - combine OP code, key ID and peer ID to wire format + * @opcode: the OP code + * @key_id: the key ID + * @peer_id: the peer ID + * + * Return: a 4 bytes integer obtained combining all input values following the + * OpenVPN wire format. This integer can then be written to the packet header. + */ +static inline u32 ovpn_opcode_compose(u8 opcode, u8 key_id, u32 peer_id) +{ + return FIELD_PREP(OVPN_OPCODE_PKTTYPE_MASK, opcode) | + FIELD_PREP(OVPN_OPCODE_KEYID_MASK, key_id) | + FIELD_PREP(OVPN_OPCODE_PEERID_MASK, peer_id); +} + #endif /* _NET_OVPN_OVPNPROTO_H_ */ diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h index af7b1f5b0ee6033ce980978667c3ee99a90e1d1b..fd19cc3081227e01c4c1ef25155de614b2dc2795 100644 --- a/drivers/net/ovpn/skb.h +++ b/drivers/net/ovpn/skb.h @@ -20,6 +20,10 @@

struct ovpn_cb { struct ovpn_peer *peer; + struct ovpn_crypto_key_slot *ks; + struct aead_request *req; + struct scatterlist *sg; + unsigned int payload_offset; };

static inline struct ovpn_cb *ovpn_skb_cb(struct sk_buff *skb)

Byte/packet counters for in-tunnel and transport streams are now initialized and updated as needed.

To be exported via netlink.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/Makefile | 1 + drivers/net/ovpn/io.c | 12 +++++++++++- drivers/net/ovpn/peer.c | 2 ++ drivers/net/ovpn/peer.h | 5 +++++ drivers/net/ovpn/stats.c | 21 +++++++++++++++++++++ drivers/net/ovpn/stats.h | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 87 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index ccdaeced1982c851475657860a005ff2b9dfbd13..d43fda72646bdc7644d9a878b56da0a0e5680c98 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -17,4 +17,5 @@ ovpn-y += netlink-gen.o ovpn-y += peer.o ovpn-y += pktid.o ovpn-y += socket.o +ovpn-y += stats.o ovpn-y += udp.o diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 124292a49cd251a3b5021dc8828813941c187e54..286611bd5c63b704a8cc4eb32c0418c524c04304 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -12,6 +12,7 @@ #include <linux/skbuff.h> #include <net/gro_cells.h> #include <net/gso.h> +#include <net/ip.h>

#include "ovpnstruct.h" #include "peer.h" @@ -55,9 +56,11 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb) /* cause packet to be "received" by the interface */ pkt_len = skb->len; ret = gro_cells_receive(&peer->ovpn->gro_cells, skb); - if (likely(ret == NET_RX_SUCCESS)) + if (likely(ret == NET_RX_SUCCESS)) { /* update RX stats with the size of decrypted packet */ + ovpn_peer_stats_increment_rx(&peer->vpn_stats, pkt_len); dev_sw_netstats_rx_add(peer->ovpn->dev, pkt_len); + } }

void ovpn_decrypt_post(void *data, int ret) @@ -155,6 +158,8 @@ void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb) struct ovpn_crypto_key_slot *ks; u8 key_id;

+ ovpn_peer_stats_increment_rx(&peer->link_stats, skb->len); + /* get the key slot matching the key ID in the received packet */ key_id = ovpn_key_id_from_skb(skb); ks = ovpn_crypto_key_id_to_slot(&peer->crypto, key_id); @@ -177,6 +182,7 @@ void ovpn_encrypt_post(void *data, int ret) struct ovpn_crypto_key_slot *ks; struct sk_buff *skb = data; struct ovpn_peer *peer; + unsigned int orig_len;

/* encryption is happening asynchronously. This function will be * called later by the crypto callback with a proper return value @@ -199,6 +205,7 @@ void ovpn_encrypt_post(void *data, int ret) goto err;

skb_mark_not_on_list(skb); + orig_len = skb->len;

switch (peer->sock->sock->sk->sk_protocol) { case IPPROTO_UDP: @@ -208,6 +215,8 @@ void ovpn_encrypt_post(void *data, int ret) /* no transport configured yet */ goto err; } + + ovpn_peer_stats_increment_tx(&peer->link_stats, orig_len); /* skb passed down the stack - don't free it */ skb = NULL; err: @@ -326,6 +335,7 @@ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev) goto drop; }

+ ovpn_peer_stats_increment_tx(&peer->vpn_stats, skb->len); ovpn_send(ovpn, skb_list.next, peer);

return NETDEV_TX_OK; diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index 456fd70ccd2a7e37f0ad1732ca9f5a07f2f54a97..0d625f065255c4947a18ae475b04c27f0cf6bb32 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -47,6 +47,8 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id) ovpn_crypto_state_init(&peer->crypto); spin_lock_init(&peer->lock); kref_init(&peer->refcount); + ovpn_peer_stats_init(&peer->vpn_stats); + ovpn_peer_stats_init(&peer->link_stats);

ret = dst_cache_init(&peer->dst_cache, GFP_KERNEL); if (ret < 0) { diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 1b427870df2cf972e0f572e046452378358f245a..61c54fb864d990ff3d746f18c9a06d4c950bd1ac 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -13,6 +13,7 @@ #include <net/dst_cache.h>

#include "crypto.h" +#include "stats.h"

/** * struct ovpn_peer - the main remote peer object @@ -25,6 +26,8 @@ * @crypto: the crypto configuration (ciphers, keys, etc..) * @dst_cache: cache for dst_entry used to send to peer * @bind: remote peer binding + * @vpn_stats: per-peer in-VPN TX/RX stays + * @link_stats: per-peer link/transport TX/RX stats * @delete_reason: why peer was deleted (i.e. timeout, transport error, ..) * @lock: protects binding to peer (bind) * @refcount: reference counter @@ -42,6 +45,8 @@ struct ovpn_peer { struct ovpn_crypto_state crypto; struct dst_cache dst_cache; struct ovpn_bind __rcu *bind; + struct ovpn_peer_stats vpn_stats; + struct ovpn_peer_stats link_stats; enum ovpn_del_peer_reason delete_reason; spinlock_t lock; /* protects bind */ struct kref refcount; diff --git a/drivers/net/ovpn/stats.c b/drivers/net/ovpn/stats.c new file mode 100644 index 0000000000000000000000000000000000000000..a383842c3449b73694c318837b0b92eb9afaec22 --- /dev/null +++ b/drivers/net/ovpn/stats.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#include <linux/atomic.h> + +#include "stats.h" + +void ovpn_peer_stats_init(struct ovpn_peer_stats *ps) +{ + atomic64_set(&ps->rx.bytes, 0); + atomic64_set(&ps->rx.packets, 0); + + atomic64_set(&ps->tx.bytes, 0); + atomic64_set(&ps->tx.packets, 0); +} diff --git a/drivers/net/ovpn/stats.h b/drivers/net/ovpn/stats.h new file mode 100644 index 0000000000000000000000000000000000000000..868f49d25eaa8fef04a02a61c363d95f9c9ef80a --- /dev/null +++ b/drivers/net/ovpn/stats.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + * Lev Stipakov lev@openvpn.net + */ + +#ifndef _NET_OVPN_OVPNSTATS_H_ +#define _NET_OVPN_OVPNSTATS_H_ + +/* one stat */ +struct ovpn_peer_stat { + atomic64_t bytes; + atomic64_t packets; +}; + +/* rx and tx stats combined */ +struct ovpn_peer_stats { + struct ovpn_peer_stat rx; + struct ovpn_peer_stat tx; +}; + +void ovpn_peer_stats_init(struct ovpn_peer_stats *ps); + +static inline void ovpn_peer_stats_increment(struct ovpn_peer_stat *stat, + const unsigned int n) +{ + atomic64_add(n, &stat->bytes); + atomic64_inc(&stat->packets); +} + +static inline void ovpn_peer_stats_increment_rx(struct ovpn_peer_stats *stats, + const unsigned int n) +{ + ovpn_peer_stats_increment(&stats->rx, n); +} + +static inline void ovpn_peer_stats_increment_tx(struct ovpn_peer_stats *stats, + const unsigned int n) +{ + ovpn_peer_stats_increment(&stats->tx, n); +} + +#endif /* _NET_OVPN_OVPNSTATS_H_ */

With this change ovpn is allowed to communicate to peers also via TCP. Parsing of incoming messages is implemented through the strparser API.

Note that ovpn redefines sk_prot and sk_socket->ops for the TCP socket used to communicate with the peer. For this reason it needs to access inet6_stream_ops, which is declared as extern in the IPv6 module, but it is not fully exported. Therefore this patch is also adding EXPORT_SYMBOL_GPL(inet6_stream_ops) to net/ipv6/af_inet6.c.

Cc: dsahern@kernel.org Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/Kconfig | 1 + drivers/net/ovpn/Makefile | 1 + drivers/net/ovpn/io.c | 4 + drivers/net/ovpn/main.c | 3 + drivers/net/ovpn/ovpnstruct.h | 1 + drivers/net/ovpn/peer.h | 39 +++ drivers/net/ovpn/socket.c | 49 +++- drivers/net/ovpn/socket.h | 9 +- drivers/net/ovpn/tcp.c | 578 ++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/tcp.h | 33 +++ drivers/net/ovpn/udp.c | 9 + net/ipv6/af_inet6.c | 1 + 12 files changed, 721 insertions(+), 7 deletions(-)

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 7d274ec48983f0ec460094ec81dc177c56f37ffe..755e79d424a5ef015054a09abce4c2817c948e1e 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -124,6 +124,7 @@ config OVPN select CRYPTO_AES select CRYPTO_GCM select CRYPTO_CHACHA20POLY1305 + select STREAM_PARSER help This module enhances the performance of the OpenVPN userspace software by offloading the data channel processing to kernelspace. diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index d43fda72646bdc7644d9a878b56da0a0e5680c98..f4d4bd87c851c8dd5b81e357315c4b22de4bd092 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -18,4 +18,5 @@ ovpn-y += peer.o ovpn-y += pktid.o ovpn-y += socket.o ovpn-y += stats.o +ovpn-y += tcp.o ovpn-y += udp.o diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 286611bd5c63b704a8cc4eb32c0418c524c04304..24a6f04b9f1cecf43e845bc948f6b9c09d0a9502 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -22,6 +22,7 @@ #include "crypto_aead.h" #include "netlink.h" #include "proto.h" +#include "tcp.h" #include "udp.h" #include "skb.h" #include "socket.h" @@ -211,6 +212,9 @@ void ovpn_encrypt_post(void *data, int ret) case IPPROTO_UDP: ovpn_udp_send_skb(peer, skb); break; + case IPPROTO_TCP: + ovpn_tcp_send_skb(peer, skb); + break; default: /* no transport configured yet */ goto err; diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c index c27e4c190f5bdf061a71c516344551ef7cd31496..b09e98080737cbb6c446d00cfaad6d2e0c716327 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -22,6 +22,7 @@ #include "io.h" #include "peer.h" #include "proto.h" +#include "tcp.h"

static int ovpn_net_init(struct net_device *dev) { @@ -229,6 +230,8 @@ static int __init ovpn_init(void) goto unreg_rtnl; }

+ ovpn_tcp_init(); + return 0;

unreg_rtnl: diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h index 1cca91d869d9e3c722a0933a426255f05daf8097..7af1f21bb5a76acb34269693bcba5ce8f832137f 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -10,6 +10,7 @@ #ifndef _NET_OVPN_OVPNSTRUCT_H_ #define _NET_OVPN_OVPNSTRUCT_H_

+#include <linux/workqueue.h> #include <net/gro_cells.h> #include <net/net_trackers.h> #include <uapi/linux/if_link.h> diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 61c54fb864d990ff3d746f18c9a06d4c950bd1ac..02e7e53792dcd69fb3d8371e9a447c6dc7aef016 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -11,6 +11,7 @@ #define _NET_OVPN_OVPNPEER_H_

#include <net/dst_cache.h> +#include <net/strparser.h>

#include "crypto.h" #include "stats.h" @@ -23,6 +24,19 @@ * @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel * @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel * @sock: the socket being used to talk to this peer + * @tcp: keeps track of TCP specific state + * @tcp.strp: stream parser context (TCP only) + * @tcp.tx_work: work for deferring outgoing packet processing (TCP only) + * @tcp.user_queue: received packets that have to go to userspace (TCP only) + * @tcp.out_queue: packets on hold while socket is taken by user (TCP only) + * @tcp.tx_in_progress: true if TX is already ongoing (TCP only) + * @tcp.out_msg.skb: packet scheduled for sending (TCP only) + * @tcp.out_msg.offset: offset where next send should start (TCP only) + * @tcp.out_msg.len: remaining data to send within packet (TCP only) + * @tcp.sk_cb.sk_data_ready: pointer to original cb (TCP only) + * @tcp.sk_cb.sk_write_space: pointer to original cb (TCP only) + * @tcp.sk_cb.prot: pointer to original prot object (TCP only) + * @tcp.sk_cb.ops: pointer to the original prot_ops object (TCP only) * @crypto: the crypto configuration (ciphers, keys, etc..) * @dst_cache: cache for dst_entry used to send to peer * @bind: remote peer binding @@ -42,6 +56,31 @@ struct ovpn_peer { struct in6_addr ipv6; } vpn_addrs; struct ovpn_socket *sock; + + /* state of the TCP reading. Needed to keep track of how much of a + * single packet has already been read from the stream and how much is + * missing + */ + struct { + struct strparser strp; + struct work_struct tx_work; + struct sk_buff_head user_queue; + struct sk_buff_head out_queue; + bool tx_in_progress; + + struct { + struct sk_buff *skb; + int offset; + int len; + } out_msg; + + struct { + void (*sk_data_ready)(struct sock *sk); + void (*sk_write_space)(struct sock *sk); + struct proto *prot; + const struct proto_ops *ops; + } sk_cb; + } tcp; struct ovpn_crypto_state crypto; struct dst_cache dst_cache; struct ovpn_bind __rcu *bind; diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c index e10590924e3f9fe605309989be84866e2e508944..312f0c19acf1548b4d44bed35e221ce94c91a8fa 100644 --- a/drivers/net/ovpn/socket.c +++ b/drivers/net/ovpn/socket.c @@ -16,6 +16,7 @@ #include "io.h" #include "peer.h" #include "socket.h" +#include "tcp.h" #include "udp.h"

static void ovpn_socket_detach(struct socket *sock) @@ -25,10 +26,26 @@ static void ovpn_socket_detach(struct socket *sock)

if (sock->sk->sk_protocol == IPPROTO_UDP) ovpn_udp_socket_detach(sock); + else if (sock->sk->sk_protocol == IPPROTO_TCP) + ovpn_tcp_socket_detach(sock);

sockfd_put(sock); }

+static void ovpn_socket_release_work(struct work_struct *work) +{ + struct ovpn_socket *sock = container_of(work, struct ovpn_socket, work); + + ovpn_socket_detach(sock->sock); + kfree_rcu(sock, rcu); +} + +static void ovpn_socket_schedule_release(struct ovpn_socket *sock) +{ + INIT_WORK(&sock->work, ovpn_socket_release_work); + schedule_work(&sock->work); +} + /** * ovpn_socket_release_kref - kref_put callback * @kref: the kref object @@ -38,8 +55,7 @@ void ovpn_socket_release_kref(struct kref *kref) struct ovpn_socket *sock = container_of(kref, struct ovpn_socket, refcount);

- ovpn_socket_detach(sock->sock); - kfree_rcu(sock, rcu); + ovpn_socket_schedule_release(sock); }

static bool ovpn_socket_hold(struct ovpn_socket *sock) @@ -53,7 +69,7 @@ static struct ovpn_socket *ovpn_socket_get(struct socket *sock)

rcu_read_lock(); ovpn_sock = rcu_dereference_sk_user_data(sock->sk); - if (WARN_ON(!ovpn_socket_hold(ovpn_sock))) + if (!ovpn_sock || WARN_ON(!ovpn_socket_hold(ovpn_sock))) ovpn_sock = NULL; rcu_read_unlock();

@@ -69,6 +85,8 @@ static int ovpn_socket_attach(struct socket *sock, struct ovpn_peer *peer)

if (sock->sk->sk_protocol == IPPROTO_UDP) ret = ovpn_udp_socket_attach(sock, peer->ovpn); + else if (sock->sk->sk_protocol == IPPROTO_TCP) + ret = ovpn_tcp_socket_attach(sock, peer);

return ret; } @@ -130,14 +148,33 @@ struct ovpn_socket *ovpn_socket_new(struct socket *sock, struct ovpn_peer *peer) }

ovpn_sock = kzalloc(sizeof(*ovpn_sock), GFP_KERNEL); - if (!ovpn_sock) - return ERR_PTR(-ENOMEM); + if (!ovpn_sock) { + ret = -ENOMEM; + goto err; + }

- ovpn_sock->ovpn = peer->ovpn; ovpn_sock->sock = sock; kref_init(&ovpn_sock->refcount);

+ /* TCP sockets are per-peer, therefore they are linked to their unique + * peer + */ + if (sock->sk->sk_protocol == IPPROTO_TCP) { + ovpn_sock->peer = peer; + ovpn_peer_hold(peer); + } else { + /* in UDP we only link the ovpn instance since the socket is + * shared among multiple peers + */ + ovpn_sock->ovpn = peer->ovpn; + netdev_hold(peer->ovpn->dev, &peer->ovpn->dev_tracker, + GFP_KERNEL); + } + rcu_assign_sk_user_data(sock->sk, ovpn_sock);

return ovpn_sock; +err: + ovpn_socket_detach(sock); + return ERR_PTR(ret); } diff --git a/drivers/net/ovpn/socket.h b/drivers/net/ovpn/socket.h index 904814d2b9e9f2b0773bf942372bcbe904ef5474..6805277853814c85c0292d3c1d2bf10e5b2e60bb 100644 --- a/drivers/net/ovpn/socket.h +++ b/drivers/net/ovpn/socket.h @@ -20,14 +20,21 @@ struct ovpn_peer; /** * struct ovpn_socket - a kernel socket referenced in the ovpn code * @ovpn: ovpn instance owning this socket (UDP only) + * @peer: unique peer transmitting over this socket (TCP only) * @sock: the low level sock object * @refcount: amount of contexts currently referencing this object + * @work: member used to schedule release routine (it may block) * @rcu: member used to schedule RCU destructor callback */ struct ovpn_socket { - struct ovpn_priv *ovpn; + union { + struct ovpn_priv *ovpn; + struct ovpn_peer *peer; + }; + struct socket *sock; struct kref refcount; + struct work_struct work; struct rcu_head rcu; };

diff --git a/drivers/net/ovpn/tcp.c b/drivers/net/ovpn/tcp.c new file mode 100644 index 0000000000000000000000000000000000000000..c9b9df206e53d17692dc717aad301ab1c0294ab7 --- /dev/null +++ b/drivers/net/ovpn/tcp.c @@ -0,0 +1,578 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2019-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#include <linux/skbuff.h> +#include <net/hotdata.h> +#include <net/inet_common.h> +#include <net/ipv6.h> +#include <net/tcp.h> +#include <net/transp_v6.h> +#include <net/route.h> +#include <trace/events/sock.h> + +#include "ovpnstruct.h" +#include "main.h" +#include "io.h" +#include "peer.h" +#include "proto.h" +#include "skb.h" +#include "tcp.h" + +static struct proto ovpn_tcp_prot __ro_after_init; +static struct proto_ops ovpn_tcp_ops __ro_after_init; +static struct proto ovpn_tcp6_prot __ro_after_init; +static struct proto_ops ovpn_tcp6_ops __ro_after_init; + +static int ovpn_tcp_parse(struct strparser *strp, struct sk_buff *skb) +{ + struct strp_msg *rxm = strp_msg(skb); + __be16 blen; + u16 len; + int err; + + /* when packets are written to the TCP stream, they are prepended with + * two bytes indicating the actual packet size. + * Here we read those two bytes and move the skb data pointer to the + * beginning of the packet + */ + + if (skb->len < rxm->offset + 2) + return 0; + + err = skb_copy_bits(skb, rxm->offset, &blen, sizeof(blen)); + if (err < 0) + return err; + + len = be16_to_cpu(blen); + if (len < 2) + return -EINVAL; + + return len + 2; +} + +/* queue skb for sending to userspace via recvmsg on the socket */ +static void ovpn_tcp_to_userspace(struct ovpn_peer *peer, struct sock *sk, + struct sk_buff *skb) +{ + skb_set_owner_r(skb, sk); + memset(skb->cb, 0, sizeof(skb->cb)); + skb_queue_tail(&peer->tcp.user_queue, skb); + peer->tcp.sk_cb.sk_data_ready(sk); +} + +static void ovpn_tcp_rcv(struct strparser *strp, struct sk_buff *skb) +{ + struct ovpn_peer *peer = container_of(strp, struct ovpn_peer, tcp.strp); + struct strp_msg *msg = strp_msg(skb); + size_t pkt_len = msg->full_len - 2; + size_t off = msg->offset + 2; + u8 opcode; + + /* ensure skb->data points to the beginning of the openvpn packet */ + if (!pskb_pull(skb, off)) { + net_warn_ratelimited("%s: packet too small for peer %u\n", + netdev_name(peer->ovpn->dev), peer->id); + goto err; + } + + /* strparser does not trim the skb for us, therefore we do it now */ + if (pskb_trim(skb, pkt_len) != 0) { + net_warn_ratelimited("%s: trimming skb failed for peer %u\n", + netdev_name(peer->ovpn->dev), peer->id); + goto err; + } + + /* we need the first byte of data to be accessible + * to extract the opcode and the key ID later on + */ + if (!pskb_may_pull(skb, 1)) { + net_warn_ratelimited("%s: packet too small to fetch opcode for peer %u\n", + netdev_name(peer->ovpn->dev), peer->id); + goto err; + } + + /* DATA_V2 packets are handled in kernel, the rest goes to user space */ + opcode = ovpn_opcode_from_skb(skb, 0); + if (unlikely(opcode != OVPN_DATA_V2)) { + if (opcode == OVPN_DATA_V1) { + net_warn_ratelimited("%s: DATA_V1 detected on the TCP stream\n", + netdev_name(peer->ovpn->dev)); + goto err; + } + + /* The packet size header must be there when sending the packet + * to userspace, therefore we put it back + */ + skb_push(skb, 2); + ovpn_tcp_to_userspace(peer, strp->sk, skb); + return; + } + + /* hold reference to peer as required by ovpn_recv(). + * + * NOTE: in this context we should already be holding a reference to + * this peer, therefore ovpn_peer_hold() is not expected to fail + */ + if (WARN_ON(!ovpn_peer_hold(peer))) + goto err; + + ovpn_recv(peer, skb); + return; +err: + dev_core_stats_rx_dropped_inc(peer->ovpn->dev); + kfree_skb(skb); + ovpn_peer_del(peer, OVPN_DEL_PEER_REASON_TRANSPORT_ERROR); +} + +static int ovpn_tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, + int flags, int *addr_len) +{ + int err = 0, off, copied = 0, ret; + struct ovpn_socket *sock; + struct ovpn_peer *peer; + struct sk_buff *skb; + + rcu_read_lock(); + sock = rcu_dereference_sk_user_data(sk); + if (!sock || !sock->peer) { + rcu_read_unlock(); + return -EBADF; + } + /* we take a reference to the peer linked to this TCP socket, because + * in turn the peer holds a reference to the socket itself. + * By doing so we also ensure that the peer stays alive along with + * the socket while executing this function + */ + ovpn_peer_hold(sock->peer); + peer = sock->peer; + rcu_read_unlock(); + + skb = __skb_recv_datagram(sk, &peer->tcp.user_queue, flags, &off, &err); + if (!skb) { + if (err == -EAGAIN && sk->sk_shutdown & RCV_SHUTDOWN) { + ret = 0; + goto out; + } + ret = err; + goto out; + } + + copied = len; + if (copied > skb->len) + copied = skb->len; + else if (copied < skb->len) + msg->msg_flags |= MSG_TRUNC; + + err = skb_copy_datagram_msg(skb, 0, msg, copied); + if (unlikely(err)) { + kfree_skb(skb); + ret = err; + goto out; + } + + if (flags & MSG_TRUNC) + copied = skb->len; + kfree_skb(skb); + ret = copied; +out: + ovpn_peer_put(peer); + return ret; +} + +void ovpn_tcp_socket_detach(struct socket *sock) +{ + struct ovpn_socket *ovpn_sock; + struct ovpn_peer *peer; + + if (!sock) + return; + + rcu_read_lock(); + ovpn_sock = rcu_dereference_sk_user_data(sock->sk); + + if (!ovpn_sock->peer) { + rcu_read_unlock(); + return; + } + + peer = ovpn_sock->peer; + strp_stop(&peer->tcp.strp); + + skb_queue_purge(&peer->tcp.user_queue); + + /* restore CBs that were saved in ovpn_sock_set_tcp_cb() */ + sock->sk->sk_data_ready = peer->tcp.sk_cb.sk_data_ready; + sock->sk->sk_write_space = peer->tcp.sk_cb.sk_write_space; + sock->sk->sk_prot = peer->tcp.sk_cb.prot; + sock->sk->sk_socket->ops = peer->tcp.sk_cb.ops; + /* drop reference to peer */ + rcu_assign_sk_user_data(sock->sk, NULL); + + rcu_read_unlock(); + + /* before canceling any ongoing work we must ensure that CBs + * have been reset to prevent workers from being re-armed + */ + barrier(); + + cancel_work_sync(&peer->tcp.tx_work); + strp_done(&peer->tcp.strp); + skb_queue_purge(&peer->tcp.out_queue); + + ovpn_peer_put(peer); +} + +static void ovpn_tcp_send_sock(struct ovpn_peer *peer) +{ + struct sk_buff *skb = peer->tcp.out_msg.skb; + + if (!skb) + return; + + if (peer->tcp.tx_in_progress) + return; + + peer->tcp.tx_in_progress = true; + + do { + int ret = skb_send_sock_locked(peer->sock->sock->sk, skb, + peer->tcp.out_msg.offset, + peer->tcp.out_msg.len); + if (unlikely(ret < 0)) { + if (ret == -EAGAIN) + goto out; + + net_warn_ratelimited("%s: TCP error to peer %u: %d\n", + netdev_name(peer->ovpn->dev), + peer->id, ret); + + /* in case of TCP error we can't recover the VPN + * stream therefore we abort the connection + */ + ovpn_peer_del(peer, + OVPN_DEL_PEER_REASON_TRANSPORT_ERROR); + break; + } + + peer->tcp.out_msg.len -= ret; + peer->tcp.out_msg.offset += ret; + } while (peer->tcp.out_msg.len > 0); + + if (!peer->tcp.out_msg.len) + dev_sw_netstats_tx_add(peer->ovpn->dev, 1, skb->len); + + kfree_skb(peer->tcp.out_msg.skb); + peer->tcp.out_msg.skb = NULL; + peer->tcp.out_msg.len = 0; + peer->tcp.out_msg.offset = 0; + +out: + peer->tcp.tx_in_progress = false; +} + +static void ovpn_tcp_tx_work(struct work_struct *work) +{ + struct ovpn_peer *peer; + + peer = container_of(work, struct ovpn_peer, tcp.tx_work); + + lock_sock(peer->sock->sock->sk); + ovpn_tcp_send_sock(peer); + release_sock(peer->sock->sock->sk); +} + +static void ovpn_tcp_send_sock_skb(struct ovpn_peer *peer, struct sk_buff *skb) +{ + if (peer->tcp.out_msg.skb) + ovpn_tcp_send_sock(peer); + + if (peer->tcp.out_msg.skb) { + dev_core_stats_rx_dropped_inc(peer->ovpn->dev); + kfree_skb(skb); + return; + } + + peer->tcp.out_msg.skb = skb; + peer->tcp.out_msg.len = skb->len; + peer->tcp.out_msg.offset = 0; + ovpn_tcp_send_sock(peer); +} + +void ovpn_tcp_send_skb(struct ovpn_peer *peer, struct sk_buff *skb) +{ + u16 len = skb->len; + + *(__be16 *)__skb_push(skb, sizeof(u16)) = htons(len); + + bh_lock_sock(peer->sock->sock->sk); + if (sock_owned_by_user(peer->sock->sock->sk)) { + if (skb_queue_len(&peer->tcp.out_queue) >= + READ_ONCE(net_hotdata.max_backlog)) { + dev_core_stats_rx_dropped_inc(peer->ovpn->dev); + kfree_skb(skb); + goto unlock; + } + __skb_queue_tail(&peer->tcp.out_queue, skb); + } else { + ovpn_tcp_send_sock_skb(peer, skb); + } +unlock: + bh_unlock_sock(peer->sock->sock->sk); +} + +static void ovpn_tcp_release(struct sock *sk) +{ + struct sk_buff_head queue; + struct ovpn_socket *sock; + struct ovpn_peer *peer; + struct sk_buff *skb; + + rcu_read_lock(); + sock = rcu_dereference_sk_user_data(sk); + if (!sock) { + rcu_read_unlock(); + goto release; + } + + peer = sock->peer; + + /* during initialization this function is called before + * assigning sock->peer + */ + if (unlikely(!peer || !ovpn_peer_hold(peer))) { + rcu_read_unlock(); + goto release; + } + rcu_read_unlock(); + + __skb_queue_head_init(&queue); + skb_queue_splice_init(&peer->tcp.out_queue, &queue); + + while ((skb = __skb_dequeue(&queue))) + ovpn_tcp_send_sock_skb(peer, skb); + + ovpn_peer_put(peer); +release: + tcp_release_cb(sk); +} + +static int ovpn_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) +{ + struct ovpn_socket *sock; + int ret, linear = PAGE_SIZE; + struct ovpn_peer *peer; + struct sk_buff *skb; + + rcu_read_lock(); + sock = rcu_dereference_sk_user_data(sk); + peer = sock->peer; + if (unlikely(!ovpn_peer_hold(peer))) { + rcu_read_unlock(); + return -EIO; + } + rcu_read_unlock(); + + lock_sock(peer->sock->sock->sk); + + if (msg->msg_flags & ~MSG_DONTWAIT) { + ret = -EOPNOTSUPP; + goto peer_free; + } + + if (peer->tcp.out_msg.skb) { + ret = -EAGAIN; + goto peer_free; + } + + if (size < linear) + linear = size; + + skb = sock_alloc_send_pskb(sk, linear, size - linear, + msg->msg_flags & MSG_DONTWAIT, &ret, 0); + if (!skb) { + net_err_ratelimited("%s: skb alloc failed: %d\n", + netdev_name(sock->peer->ovpn->dev), ret); + goto peer_free; + } + + skb_put(skb, linear); + skb->len = size; + skb->data_len = size - linear; + + ret = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size); + if (ret) { + kfree_skb(skb); + net_err_ratelimited("%s: skb copy from iter failed: %d\n", + netdev_name(sock->peer->ovpn->dev), ret); + goto peer_free; + } + + ovpn_tcp_send_sock_skb(sock->peer, skb); + ret = size; +peer_free: + release_sock(peer->sock->sock->sk); + ovpn_peer_put(peer); + return ret; +} + +static void ovpn_tcp_data_ready(struct sock *sk) +{ + struct ovpn_socket *sock; + + trace_sk_data_ready(sk); + + rcu_read_lock(); + sock = rcu_dereference_sk_user_data(sk); + strp_data_ready(&sock->peer->tcp.strp); + rcu_read_unlock(); +} + +static void ovpn_tcp_write_space(struct sock *sk) +{ + struct ovpn_socket *sock; + + rcu_read_lock(); + sock = rcu_dereference_sk_user_data(sk); + schedule_work(&sock->peer->tcp.tx_work); + sock->peer->tcp.sk_cb.sk_write_space(sk); + rcu_read_unlock(); +} + +static void ovpn_tcp_build_protos(struct proto *new_prot, + struct proto_ops *new_ops, + const struct proto *orig_prot, + const struct proto_ops *orig_ops); + +/* Set TCP encapsulation callbacks */ +int ovpn_tcp_socket_attach(struct socket *sock, struct ovpn_peer *peer) +{ + struct strp_callbacks cb = { + .rcv_msg = ovpn_tcp_rcv, + .parse_msg = ovpn_tcp_parse, + }; + int ret; + + /* make sure no pre-existing encapsulation handler exists */ + if (sock->sk->sk_user_data) + return -EBUSY; + + /* sanity check */ + if (sock->sk->sk_protocol != IPPROTO_TCP) { + net_err_ratelimited("%s: provided socket is not TCP as expected\n", + netdev_name(peer->ovpn->dev)); + return -EINVAL; + } + + /* only a fully connected socket are expected. Connection should be + * handled in userspace + */ + if (sock->sk->sk_state != TCP_ESTABLISHED) { + net_err_ratelimited("%s: provided TCP socket is not in ESTABLISHED state: %d\n", + netdev_name(peer->ovpn->dev), + sock->sk->sk_state); + return -EINVAL; + } + + lock_sock(sock->sk); + + ret = strp_init(&peer->tcp.strp, sock->sk, &cb); + if (ret < 0) { + DEBUG_NET_WARN_ON_ONCE(1); + release_sock(sock->sk); + return ret; + } + + INIT_WORK(&peer->tcp.tx_work, ovpn_tcp_tx_work); + __sk_dst_reset(sock->sk); + skb_queue_head_init(&peer->tcp.user_queue); + skb_queue_head_init(&peer->tcp.out_queue); + + /* save current CBs so that they can be restored upon socket release */ + peer->tcp.sk_cb.sk_data_ready = sock->sk->sk_data_ready; + peer->tcp.sk_cb.sk_write_space = sock->sk->sk_write_space; + peer->tcp.sk_cb.prot = sock->sk->sk_prot; + peer->tcp.sk_cb.ops = sock->sk->sk_socket->ops; + + /* assign our static CBs and prot/ops */ + sock->sk->sk_data_ready = ovpn_tcp_data_ready; + sock->sk->sk_write_space = ovpn_tcp_write_space; + + if (sock->sk->sk_family == AF_INET) { + sock->sk->sk_prot = &ovpn_tcp_prot; + sock->sk->sk_socket->ops = &ovpn_tcp_ops; + } else { + sock->sk->sk_prot = &ovpn_tcp6_prot; + sock->sk->sk_socket->ops = &ovpn_tcp6_ops; + } + + /* avoid using task_frag */ + sock->sk->sk_allocation = GFP_ATOMIC; + sock->sk->sk_use_task_frag = false; + + /* enqueue the RX worker */ + strp_check_rcv(&peer->tcp.strp); + + release_sock(sock->sk); + return 0; +} + +static void ovpn_tcp_close(struct sock *sk, long timeout) +{ + struct ovpn_socket *sock; + + rcu_read_lock(); + sock = rcu_dereference_sk_user_data(sk); + + strp_stop(&sock->peer->tcp.strp); + + tcp_close(sk, timeout); + + ovpn_peer_del(sock->peer, OVPN_DEL_PEER_REASON_TRANSPORT_ERROR); + rcu_read_unlock(); +} + +static __poll_t ovpn_tcp_poll(struct file *file, struct socket *sock, + poll_table *wait) +{ + __poll_t mask = datagram_poll(file, sock, wait); + struct ovpn_socket *ovpn_sock; + + rcu_read_lock(); + ovpn_sock = rcu_dereference_sk_user_data(sock->sk); + if (!skb_queue_empty(&ovpn_sock->peer->tcp.user_queue)) + mask |= EPOLLIN | EPOLLRDNORM; + rcu_read_unlock(); + + return mask; +} + +static void ovpn_tcp_build_protos(struct proto *new_prot, + struct proto_ops *new_ops, + const struct proto *orig_prot, + const struct proto_ops *orig_ops) +{ + memcpy(new_prot, orig_prot, sizeof(*new_prot)); + memcpy(new_ops, orig_ops, sizeof(*new_ops)); + new_prot->recvmsg = ovpn_tcp_recvmsg; + new_prot->sendmsg = ovpn_tcp_sendmsg; + new_prot->close = ovpn_tcp_close; + new_prot->release_cb = ovpn_tcp_release; + new_ops->poll = ovpn_tcp_poll; +} + +/* Initialize TCP static objects */ +void __init ovpn_tcp_init(void) +{ + ovpn_tcp_build_protos(&ovpn_tcp_prot, &ovpn_tcp_ops, &tcp_prot, + &inet_stream_ops); + +#if IS_ENABLED(CONFIG_IPV6) + ovpn_tcp_build_protos(&ovpn_tcp6_prot, &ovpn_tcp6_ops, &tcpv6_prot, + &inet6_stream_ops); +#endif +} diff --git a/drivers/net/ovpn/tcp.h b/drivers/net/ovpn/tcp.h new file mode 100644 index 0000000000000000000000000000000000000000..994c18fd95468141dc4adfe5ff3e7eeade0bdbd4 --- /dev/null +++ b/drivers/net/ovpn/tcp.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2019-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_TCP_H_ +#define _NET_OVPN_TCP_H_ + +#include <linux/net.h> +#include <linux/skbuff.h> +#include <linux/types.h> + +#include "peer.h" +#include "skb.h" +#include "socket.h" + +void __init ovpn_tcp_init(void); + +int ovpn_tcp_socket_attach(struct socket *sock, struct ovpn_peer *peer); +void ovpn_tcp_socket_detach(struct socket *sock); + +/* Prepare skb and enqueue it for sending to peer. + * + * Preparation consist in prepending the skb payload with its size. + * Required by the OpenVPN protocol in order to extract packets from + * the TCP stream on the receiver side. + */ +void ovpn_tcp_send_skb(struct ovpn_peer *peer, struct sk_buff *skb); + +#endif /* _NET_OVPN_TCP_H_ */ diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c index 5932f8b5dfad1004e9e76e5fabfbb71bd9a94d4d..c7d083b2526987c1479f69a342fdbb264213c5cc 100644 --- a/drivers/net/ovpn/udp.c +++ b/drivers/net/ovpn/udp.c @@ -383,6 +383,15 @@ int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_priv *ovpn) void ovpn_udp_socket_detach(struct socket *sock) { struct udp_tunnel_sock_cfg cfg = { }; + struct ovpn_priv *ovpn; + + rcu_read_lock(); + ovpn = ovpn_from_udp_sock(sock->sk); + if (ovpn) + /* drop reference to netdev held in sk_user_data */ + netdev_put(ovpn->dev, &ovpn->dev_tracker); + rcu_read_unlock();

setup_udp_tunnel_sock(sock_net(sock->sk), sock, &cfg); + rcu_assign_sk_user_data(sock->sk, NULL); } diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index f60ec8b0f8ea40b2d635d802a3bc4f9b9d844417..3e812187e125cec7deac88413b85a35dd5b22a2d 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -715,6 +715,7 @@ const struct proto_ops inet6_stream_ops = { #endif .set_rcvlowat = tcp_set_rcvlowat, }; +EXPORT_SYMBOL_GPL(inet6_stream_ops);

const struct proto_ops inet6_dgram_ops = { .family = PF_INET6,

With this change an ovpn instance will be able to stay connected to multiple remote endpoints.

This functionality is strictly required when running ovpn on an OpenVPN server.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/main.c | 67 ++++++++++++++++- drivers/net/ovpn/ovpnstruct.h | 16 ++++ drivers/net/ovpn/peer.c | 166 ++++++++++++++++++++++++++++++++++++++++-- drivers/net/ovpn/peer.h | 9 +++ 4 files changed, 249 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c index b09e98080737cbb6c446d00cfaad6d2e0c716327..bd0d791cf9ccad7563f89e96b9c443d52b34e8bf 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -24,6 +24,13 @@ #include "proto.h" #include "tcp.h"

+static void ovpn_priv_free(struct net_device *net) +{ + struct ovpn_priv *ovpn = netdev_priv(net); + + kfree(ovpn->peers); +} + static int ovpn_net_init(struct net_device *dev) { struct ovpn_priv *ovpn = netdev_priv(dev); @@ -99,6 +106,8 @@ static void ovpn_setup(struct net_device *dev)

dev->netdev_ops = &ovpn_netdev_ops;

+ dev->priv_destructor = ovpn_priv_free; + dev->hard_header_len = 0; dev->addr_len = 0; dev->mtu = ETH_DATA_LEN - OVPN_HEAD_ROOM; @@ -120,12 +129,50 @@ static void ovpn_setup(struct net_device *dev) SET_NETDEV_DEVTYPE(dev, &ovpn_type); }

+static int ovpn_mp_alloc(struct ovpn_priv *ovpn) +{ + struct in_device *dev_v4; + int i; + + if (ovpn->mode != OVPN_MODE_MP) + return 0; + + dev_v4 = __in_dev_get_rtnl(ovpn->dev); + if (dev_v4) { + /* disable redirects as Linux gets confused by ovpn + * handling same-LAN routing. + * This happens because a multipeer interface is used as + * relay point between hosts in the same subnet, while + * in a classic LAN this would not be needed because the + * two hosts would be able to talk directly. + */ + IN_DEV_CONF_SET(dev_v4, SEND_REDIRECTS, false); + IPV4_DEVCONF_ALL(dev_net(ovpn->dev), SEND_REDIRECTS) = false; + } + + /* the peer container is fairly large, therefore we allocate it only in + * MP mode + */ + ovpn->peers = kzalloc(sizeof(*ovpn->peers), GFP_KERNEL); + if (!ovpn->peers) + return -ENOMEM; + + for (i = 0; i < ARRAY_SIZE(ovpn->peers->by_id); i++) { + INIT_HLIST_HEAD(&ovpn->peers->by_id[i]); + INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_vpn_addr[i], i); + INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_transp_addr[i], i); + } + + return 0; +} + static int ovpn_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { struct ovpn_priv *ovpn = netdev_priv(dev); enum ovpn_mode mode = OVPN_MODE_P2P; + int err;

if (data && data[IFLA_OVPN_MODE]) { mode = nla_get_u8(data[IFLA_OVPN_MODE]); @@ -136,6 +183,10 @@ static int ovpn_newlink(struct net *src_net, struct net_device *dev, ovpn->mode = mode; spin_lock_init(&ovpn->lock);

+ err = ovpn_mp_alloc(ovpn); + if (err < 0) + return err; + /* turn carrier explicitly off after registration, this way state is * clearly defined */ @@ -184,14 +235,26 @@ static int ovpn_netdev_notifier_call(struct notifier_block *nb, netif_carrier_off(dev); ovpn->registered = false;

- if (ovpn->mode == OVPN_MODE_P2P) + switch (ovpn->mode) { + case OVPN_MODE_P2P: ovpn_peer_release_p2p(ovpn, OVPN_DEL_PEER_REASON_TEARDOWN); + break; + case OVPN_MODE_MP: + ovpn_peers_free(ovpn, OVPN_DEL_PEER_REASON_TEARDOWN); + break; + } break; case NETDEV_DOWN: - if (ovpn->mode == OVPN_MODE_P2P) + switch (ovpn->mode) { + case OVPN_MODE_P2P: ovpn_peer_release_p2p(ovpn, OVPN_DEL_PEER_REASON_ADMINDOWN); + break; + case OVPN_MODE_MP: + ovpn_peers_free(ovpn, OVPN_DEL_PEER_REASON_ADMINDOWN); + break; + } break; case NETDEV_POST_INIT: case NETDEV_GOING_DOWN: diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h index 7af1f21bb5a76acb34269693bcba5ce8f832137f..bca13e8e4439c2f217ae17896f114347e8aefd06 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -16,6 +16,20 @@ #include <uapi/linux/if_link.h> #include <uapi/linux/ovpn.h>

+/** + * struct ovpn_peer_collection - container of peers for MultiPeer mode + * @by_id: table of peers index by ID + * @by_vpn_addr: table of peers indexed by VPN IP address (items can be + * rehashed on the fly due to peer IP change) + * @by_transp_addr: table of peers indexed by transport address (items can be + * rehashed on the fly due to peer IP change) + */ +struct ovpn_peer_collection { + DECLARE_HASHTABLE(by_id, 12); + struct hlist_nulls_head by_vpn_addr[1 << 12]; + struct hlist_nulls_head by_transp_addr[1 << 12]; +}; + /** * struct ovpn_priv - per ovpn interface state * @dev: the actual netdev representing the tunnel @@ -23,6 +37,7 @@ * @registered: whether dev is still registered with netdev or not * @mode: device operation mode (i.e. p2p, mp, ..) * @lock: protect this object + * @peers: data structures holding multi-peer references * @peer: in P2P mode, this is the only remote peer * @gro_cells: pointer to the Generic Receive Offload cell */ @@ -32,6 +47,7 @@ struct ovpn_priv { bool registered; enum ovpn_mode mode; spinlock_t lock; /* protect writing to the ovpn_priv object */ + struct ovpn_peer_collection *peers; struct ovpn_peer __rcu *peer; struct gro_cells gro_cells; }; diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index 0d625f065255c4947a18ae475b04c27f0cf6bb32..9f213ccacfaf8170b9c23730498f156360774d7e 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -9,6 +9,7 @@

#include <linux/skbuff.h> #include <linux/list.h> +#include <linux/hashtable.h>

#include "ovpnstruct.h" #include "bind.h" @@ -317,6 +318,89 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb, return match; }

+#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ + typeof(_tbl) *__tbl = &(_tbl); \ + (&(*__tbl)[jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl)]); }) \ + +/** + * ovpn_peer_add_mp - add peer to related tables in a MP instance + * @ovpn: the instance to add the peer to + * @peer: the peer to add + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_peer_add_mp(struct ovpn_priv *ovpn, struct ovpn_peer *peer) +{ + struct sockaddr_storage sa = { 0 }; + struct hlist_nulls_head *nhead; + struct sockaddr_in6 *sa6; + struct sockaddr_in *sa4; + struct ovpn_bind *bind; + struct ovpn_peer *tmp; + size_t salen; + int ret = 0; + + spin_lock_bh(&ovpn->lock); + /* do not add duplicates */ + tmp = ovpn_peer_get_by_id(ovpn, peer->id); + if (tmp) { + ovpn_peer_put(tmp); + ret = -EEXIST; + goto out; + } + + bind = rcu_dereference_protected(peer->bind, true); + /* peers connected via TCP have bind == NULL */ + if (bind) { + switch (bind->remote.in4.sin_family) { + case AF_INET: + sa4 = (struct sockaddr_in *)&sa; + + sa4->sin_family = AF_INET; + sa4->sin_addr.s_addr = bind->remote.in4.sin_addr.s_addr; + sa4->sin_port = bind->remote.in4.sin_port; + salen = sizeof(*sa4); + break; + case AF_INET6: + sa6 = (struct sockaddr_in6 *)&sa; + + sa6->sin6_family = AF_INET6; + sa6->sin6_addr = bind->remote.in6.sin6_addr; + sa6->sin6_port = bind->remote.in6.sin6_port; + salen = sizeof(*sa6); + break; + default: + ret = -EPROTONOSUPPORT; + goto out; + } + + nhead = ovpn_get_hash_head(ovpn->peers->by_transp_addr, &sa, + salen); + hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead); + } + + hlist_add_head_rcu(&peer->hash_entry_id, + ovpn_get_hash_head(ovpn->peers->by_id, &peer->id, + sizeof(peer->id))); + + if (peer->vpn_addrs.ipv4.s_addr != htonl(INADDR_ANY)) { + nhead = ovpn_get_hash_head(ovpn->peers->by_vpn_addr, + &peer->vpn_addrs.ipv4, + sizeof(peer->vpn_addrs.ipv4)); + hlist_nulls_add_head_rcu(&peer->hash_entry_addr4, nhead); + } + + if (!ipv6_addr_any(&peer->vpn_addrs.ipv6)) { + nhead = ovpn_get_hash_head(ovpn->peers->by_vpn_addr, + &peer->vpn_addrs.ipv6, + sizeof(peer->vpn_addrs.ipv6)); + hlist_nulls_add_head_rcu(&peer->hash_entry_addr6, nhead); + } +out: + spin_unlock_bh(&ovpn->lock); + return ret; +} + /** * ovpn_peer_add_p2p - add peer to related tables in a P2P instance * @ovpn: the instance to add the peer to @@ -359,17 +443,35 @@ static int ovpn_peer_add_p2p(struct ovpn_priv *ovpn, struct ovpn_peer *peer) int ovpn_peer_add(struct ovpn_priv *ovpn, struct ovpn_peer *peer) { switch (ovpn->mode) { + case OVPN_MODE_MP: + return ovpn_peer_add_mp(ovpn, peer); case OVPN_MODE_P2P: return ovpn_peer_add_p2p(ovpn, peer); - default: - return -EOPNOTSUPP; } + + return -EOPNOTSUPP; }

+/** + * ovpn_peer_remove - remove peer from internal state + * @peer: the peer to remove + * @reason: the delete reason to attach to the peer + * + * This function assumes that the peer is part of the ovpn peer + * collection and it will decrease the reference counter at the end + */ static void ovpn_peer_remove(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason) { + lockdep_assert_held(&peer->ovpn->lock); + switch (peer->ovpn->mode) { + case OVPN_MODE_MP: + hlist_del_init_rcu(&peer->hash_entry_id); + hlist_nulls_del_init_rcu(&peer->hash_entry_addr4); + hlist_nulls_del_init_rcu(&peer->hash_entry_addr6); + hlist_nulls_del_init_rcu(&peer->hash_entry_transp_addr); + break; case OVPN_MODE_P2P: RCU_INIT_POINTER(peer->ovpn->peer, NULL); /* in P2P mode the carrier is switched off when the peer is @@ -377,8 +479,6 @@ static void ovpn_peer_remove(struct ovpn_peer *peer, */ netif_carrier_off(peer->ovpn->dev); break; - default: - return; }

peer->delete_reason = reason; @@ -389,6 +489,33 @@ static void ovpn_peer_remove(struct ovpn_peer *peer, ovpn_peer_put(peer); }

+/** + * ovpn_peer_del_mp - delete peer from related tables in a MP instance + * @peer: the peer to delete + * @reason: reason why the peer was deleted (sent to userspace) + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_peer_del_mp(struct ovpn_peer *peer, + enum ovpn_del_peer_reason reason) +{ + struct ovpn_peer *tmp; + int ret = -ENOENT; + + lockdep_assert_held(&peer->ovpn->lock); + + tmp = ovpn_peer_get_by_id(peer->ovpn, peer->id); + if (tmp == peer) { + ovpn_peer_remove(peer, reason); + ret = 0; + } + + if (tmp) + ovpn_peer_put(tmp); + + return ret; +} + /** * ovpn_peer_del_p2p - delete peer from related tables in a P2P instance * @peer: the peer to delete @@ -442,10 +569,35 @@ void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, */ int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason) { + int ret = -EOPNOTSUPP; + + spin_lock_bh(&peer->ovpn->lock); switch (peer->ovpn->mode) { + case OVPN_MODE_MP: + ret = ovpn_peer_del_mp(peer, reason); + break; case OVPN_MODE_P2P: - return ovpn_peer_del_p2p(peer, reason); - default: - return -EOPNOTSUPP; + ret = ovpn_peer_del_p2p(peer, reason); + break; } + spin_unlock_bh(&peer->ovpn->lock); + return ret; +} + +/** + * ovpn_peers_free - free all peers in the instance + * @ovpn: the instance whose peers should be released + * @reason: the reason for releasing all peers + */ +void ovpn_peers_free(struct ovpn_priv *ovpn, + enum ovpn_del_peer_reason reason) +{ + struct hlist_node *tmp; + struct ovpn_peer *peer; + int bkt; + + spin_lock_bh(&ovpn->lock); + hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id) + ovpn_peer_remove(peer, reason); + spin_unlock_bh(&ovpn->lock); } diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 02e7e53792dcd69fb3d8371e9a447c6dc7aef016..636245521f9502ce9139affd7b90d3ba918d1ea6 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -23,6 +23,10 @@ * @vpn_addrs: IP addresses assigned over the tunnel * @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel * @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel + * @hash_entry_id: entry in the peer ID hashtable + * @hash_entry_addr4: entry in the peer IPv4 hashtable + * @hash_entry_addr6: entry in the peer IPv6 hashtable + * @hash_entry_transp_addr: entry in the peer transport address hashtable * @sock: the socket being used to talk to this peer * @tcp: keeps track of TCP specific state * @tcp.strp: stream parser context (TCP only) @@ -55,6 +59,10 @@ struct ovpn_peer { struct in_addr ipv4; struct in6_addr ipv6; } vpn_addrs; + struct hlist_node hash_entry_id; + struct hlist_nulls_node hash_entry_addr4; + struct hlist_nulls_node hash_entry_addr6; + struct hlist_nulls_node hash_entry_transp_addr; struct ovpn_socket *sock;

/* state of the TCP reading. Needed to keep track of how much of a @@ -120,6 +128,7 @@ int ovpn_peer_add(struct ovpn_priv *ovpn, struct ovpn_peer *peer); int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason); void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, enum ovpn_del_peer_reason reason); +void ovpn_peers_free(struct ovpn_priv *ovpn, enum ovpn_del_peer_reason reason);

struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn, struct sk_buff *skb);

OpenVPN supports configuring a periodic keepalive packet. message to allow the remote endpoint detect link failures.

This change implements the keepalive sending and timer expiring logic.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/io.c | 77 +++++++++++++++++ drivers/net/ovpn/io.h | 5 ++ drivers/net/ovpn/main.c | 3 + drivers/net/ovpn/ovpnstruct.h | 2 + drivers/net/ovpn/peer.c | 190 ++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/peer.h | 23 ++++- 6 files changed, 296 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 24a6f04b9f1cecf43e845bc948f6b9c09d0a9502..0bab35fab06b4399c57e49732453df2fc12e9334 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -27,6 +27,33 @@ #include "skb.h" #include "socket.h"

+const unsigned char ovpn_keepalive_message[OVPN_KEEPALIVE_SIZE] = { + 0x2a, 0x18, 0x7b, 0xf3, 0x64, 0x1e, 0xb4, 0xcb, + 0x07, 0xed, 0x2d, 0x0a, 0x98, 0x1f, 0xc7, 0x48 +}; + +/** + * ovpn_is_keepalive - check if skb contains a keepalive message + * @skb: packet to check + * + * Assumes that the first byte of skb->data is defined. + * + * Return: true if skb contains a keepalive or false otherwise + */ +static bool ovpn_is_keepalive(struct sk_buff *skb) +{ + if (*skb->data != ovpn_keepalive_message[0]) + return false; + + if (skb->len != OVPN_KEEPALIVE_SIZE) + return false; + + if (!pskb_may_pull(skb, OVPN_KEEPALIVE_SIZE)) + return false; + + return !memcmp(skb->data, ovpn_keepalive_message, OVPN_KEEPALIVE_SIZE); +} + /* Called after decrypt to write the IP packet to the device. * This method is expected to manage/free the skb. */ @@ -104,6 +131,9 @@ void ovpn_decrypt_post(void *data, int ret) goto drop; }

+ /* keep track of last received authenticated packet for keepalive */ + WRITE_ONCE(peer->last_recv, ktime_get_real_seconds()); + /* point to encapsulated IP packet */ __skb_pull(skb, payload_offset);

@@ -121,6 +151,13 @@ void ovpn_decrypt_post(void *data, int ret) goto drop; }

+ if (ovpn_is_keepalive(skb)) { + net_dbg_ratelimited("%s: ping received from peer %u\n", + netdev_name(peer->ovpn->dev), + peer->id); + goto drop_nocount; + } + net_info_ratelimited("%s: unsupported protocol received from peer %u\n", netdev_name(peer->ovpn->dev), peer->id); goto drop; @@ -146,6 +183,7 @@ void ovpn_decrypt_post(void *data, int ret) drop: if (unlikely(skb)) dev_core_stats_rx_dropped_inc(peer->ovpn->dev); +drop_nocount: if (likely(peer)) ovpn_peer_put(peer); if (likely(ks)) @@ -221,6 +259,8 @@ void ovpn_encrypt_post(void *data, int ret) }

ovpn_peer_stats_increment_tx(&peer->link_stats, orig_len); + /* keep track of last sent packet for keepalive */ + WRITE_ONCE(peer->last_sent, ktime_get_real_seconds()); /* skb passed down the stack - don't free it */ skb = NULL; err: @@ -350,3 +390,40 @@ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev) kfree_skb_list(skb); return NET_XMIT_DROP; } + +/** + * ovpn_xmit_special - encrypt and transmit an out-of-band message to peer + * @peer: peer to send the message to + * @data: message content + * @len: message length + * + * Assumes that caller holds a reference to peer + */ +void ovpn_xmit_special(struct ovpn_peer *peer, const void *data, + const unsigned int len) +{ + struct ovpn_priv *ovpn; + struct sk_buff *skb; + + ovpn = peer->ovpn; + if (unlikely(!ovpn)) + return; + + skb = alloc_skb(256 + len, GFP_ATOMIC); + if (unlikely(!skb)) + return; + + skb_reserve(skb, 128); + skb->priority = TC_PRIO_BESTEFFORT; + __skb_put_data(skb, data, len); + + /* increase reference counter when passing peer to sending queue */ + if (!ovpn_peer_hold(peer)) { + netdev_dbg(ovpn->dev, + "cannot hold peer reference for sending special packet\n"); + kfree_skb(skb); + return; + } + + ovpn_send(ovpn, skb, peer); +} diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h index 5f9c7eba37b132bcf8c0ebad60af9171e46bf3e8..1186bb6a5f1b0411a825a295d0e6e21c32972e84 100644 --- a/drivers/net/ovpn/io.h +++ b/drivers/net/ovpn/io.h @@ -19,9 +19,14 @@ /* max padding required by encryption */ #define OVPN_MAX_PADDING 16

+#define OVPN_KEEPALIVE_SIZE 16 +extern const unsigned char ovpn_keepalive_message[OVPN_KEEPALIVE_SIZE]; + netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev);

void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb); +void ovpn_xmit_special(struct ovpn_peer *peer, const void *data, + const unsigned int len);

void ovpn_encrypt_post(void *data, int ret); void ovpn_decrypt_post(void *data, int ret); diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c index bd0d791cf9ccad7563f89e96b9c443d52b34e8bf..6b3a59e75e5aa918b28957c073990be9fb1d2124 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -182,6 +182,7 @@ static int ovpn_newlink(struct net *src_net, struct net_device *dev, ovpn->dev = dev; ovpn->mode = mode; spin_lock_init(&ovpn->lock); + INIT_DELAYED_WORK(&ovpn->keepalive_work, ovpn_peer_keepalive_work);

err = ovpn_mp_alloc(ovpn); if (err < 0) @@ -235,6 +236,8 @@ static int ovpn_netdev_notifier_call(struct notifier_block *nb, netif_carrier_off(dev); ovpn->registered = false;

+ cancel_delayed_work_sync(&ovpn->keepalive_work); + switch (ovpn->mode) { case OVPN_MODE_P2P: ovpn_peer_release_p2p(ovpn, diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h index bca13e8e4439c2f217ae17896f114347e8aefd06..95469ff96da9fb939d064af9ebb97220ccb4566c 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -40,6 +40,7 @@ struct ovpn_peer_collection { * @peers: data structures holding multi-peer references * @peer: in P2P mode, this is the only remote peer * @gro_cells: pointer to the Generic Receive Offload cell + * @keepalive_work: struct used to schedule keepalive periodic job */ struct ovpn_priv { struct net_device *dev; @@ -50,6 +51,7 @@ struct ovpn_priv { struct ovpn_peer_collection *peers; struct ovpn_peer __rcu *peer; struct gro_cells gro_cells; + struct delayed_work keepalive_work; };

#endif /* _NET_OVPN_OVPNSTRUCT_H_ */ diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index f1763fb3d044aa87fde7f877cf3e83ea1e19ae11..7908a4025352094b9c1ad5a75e1e9e2dfb86cb78 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -22,6 +22,46 @@ #include "peer.h" #include "socket.h"

+/** + * ovpn_peer_keepalive_set - configure keepalive values for peer + * @peer: the peer to configure + * @interval: outgoing keepalive interval + * @timeout: incoming keepalive timeout + */ +void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout) +{ + time64_t now = ktime_get_real_seconds(); + + netdev_dbg(peer->ovpn->dev, + "scheduling keepalive for peer %u: interval=%u timeout=%u\n", + peer->id, interval, timeout); + + peer->keepalive_interval = interval; + WRITE_ONCE(peer->last_sent, now); + peer->keepalive_xmit_exp = now + interval; + + peer->keepalive_timeout = timeout; + WRITE_ONCE(peer->last_recv, now); + peer->keepalive_recv_exp = now + timeout; + + /* now that interval and timeout have been changed, kick + * off the worker so that the next delay can be recomputed + */ + mod_delayed_work(system_wq, &peer->ovpn->keepalive_work, 0); +} + +static void ovpn_peer_keepalive_send(struct work_struct *work) +{ + struct ovpn_peer *peer = container_of(work, struct ovpn_peer, + keepalive_work); + + local_bh_disable(); + ovpn_xmit_special(peer, ovpn_keepalive_message, + sizeof(ovpn_keepalive_message)); + local_bh_enable(); + ovpn_peer_put(peer); +} + /** * ovpn_peer_new - allocate and initialize a new peer object * @ovpn: the openvpn instance inside which the peer should be created @@ -51,6 +91,7 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id) kref_init(&peer->refcount); ovpn_peer_stats_init(&peer->vpn_stats); ovpn_peer_stats_init(&peer->link_stats); + INIT_WORK(&peer->keepalive_work, ovpn_peer_keepalive_send);

ret = dst_cache_init(&peer->dst_cache, GFP_KERNEL); if (ret < 0) { @@ -882,3 +923,152 @@ void ovpn_peers_free(struct ovpn_priv *ovpn, ovpn_peer_remove(peer, reason); spin_unlock_bh(&ovpn->lock); } + +static time64_t ovpn_peer_keepalive_work_single(struct ovpn_peer *peer, + time64_t now) +{ + time64_t last_recv, last_sent, next_run1, next_run2; + unsigned long timeout, interval; + bool expired; + + spin_lock_bh(&peer->lock); + /* we expect both timers to be configured at the same time, + * therefore bail out if either is not set + */ + if (!peer->keepalive_timeout || !peer->keepalive_interval) { + spin_unlock_bh(&peer->lock); + return 0; + } + + /* check for peer timeout */ + expired = false; + timeout = peer->keepalive_timeout; + last_recv = READ_ONCE(peer->last_recv); + if (now < last_recv + timeout) { + peer->keepalive_recv_exp = last_recv + timeout; + next_run1 = peer->keepalive_recv_exp; + } else if (peer->keepalive_recv_exp > now) { + next_run1 = peer->keepalive_recv_exp; + } else { + expired = true; + } + + if (expired) { + /* peer is dead -> kill it and move on */ + spin_unlock_bh(&peer->lock); + netdev_dbg(peer->ovpn->dev, "peer %u expired\n", + peer->id); + ovpn_peer_remove(peer, OVPN_DEL_PEER_REASON_EXPIRED); + return 0; + } + + /* check for peer keepalive */ + expired = false; + interval = peer->keepalive_interval; + last_sent = READ_ONCE(peer->last_sent); + if (now < last_sent + interval) { + peer->keepalive_xmit_exp = last_sent + interval; + next_run2 = peer->keepalive_xmit_exp; + } else if (peer->keepalive_xmit_exp > now) { + next_run2 = peer->keepalive_xmit_exp; + } else { + expired = true; + next_run2 = now + interval; + } + spin_unlock_bh(&peer->lock); + + if (expired) { + /* a keepalive packet is required */ + netdev_dbg(peer->ovpn->dev, + "sending keepalive to peer %u\n", + peer->id); + if (schedule_work(&peer->keepalive_work)) + ovpn_peer_hold(peer); + } + + if (next_run1 < next_run2) + return next_run1; + + return next_run2; +} + +static time64_t ovpn_peer_keepalive_work_mp(struct ovpn_priv *ovpn, + time64_t now) +{ + time64_t tmp_next_run, next_run = 0; + struct hlist_node *tmp; + struct ovpn_peer *peer; + int bkt; + + lockdep_assert_held(&ovpn->lock); + + hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id) { + tmp_next_run = ovpn_peer_keepalive_work_single(peer, now); + if (!tmp_next_run) + continue; + + /* the next worker run will be scheduled based on the shortest + * required interval across all peers + */ + if (!next_run || tmp_next_run < next_run) + next_run = tmp_next_run; + } + + return next_run; +} + +static time64_t ovpn_peer_keepalive_work_p2p(struct ovpn_priv *ovpn, + time64_t now) +{ + struct ovpn_peer *peer; + time64_t next_run = 0; + + lockdep_assert_held(&ovpn->lock); + + peer = rcu_dereference_protected(ovpn->peer, + lockdep_is_held(&ovpn->lock)); + if (peer) + next_run = ovpn_peer_keepalive_work_single(peer, now); + + return next_run; +} + +/** + * ovpn_peer_keepalive_work - run keepalive logic on each known peer + * @work: pointer to the work member of the related ovpn object + * + * Each peer has two timers (if configured): + * 1. peer timeout: when no data is received for a certain interval, + * the peer is considered dead and it gets killed. + * 2. peer keepalive: when no data is sent to a certain peer for a + * certain interval, a special 'keepalive' packet is explicitly sent. + * + * This function iterates across the whole peer collection while + * checking the timers described above. + */ +void ovpn_peer_keepalive_work(struct work_struct *work) +{ + struct ovpn_priv *ovpn = container_of(work, struct ovpn_priv, + keepalive_work.work); + time64_t next_run = 0, now = ktime_get_real_seconds(); + + spin_lock_bh(&ovpn->lock); + switch (ovpn->mode) { + case OVPN_MODE_MP: + next_run = ovpn_peer_keepalive_work_mp(ovpn, now); + break; + case OVPN_MODE_P2P: + next_run = ovpn_peer_keepalive_work_p2p(ovpn, now); + break; + } + spin_unlock_bh(&ovpn->lock); + + /* prevent rearming if the interface is being destroyed */ + if (next_run > 0 && ovpn->registered) { + netdev_dbg(ovpn->dev, + "scheduling keepalive work: now=%llu next_run=%llu delta=%llu\n", + next_run, now, next_run - now); + schedule_delayed_work(&ovpn->keepalive_work, + (next_run - now) * HZ); + } +} diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 636245521f9502ce9139affd7b90d3ba918d1ea6..4316051a12f0b8ada5110dd7aa71afedf29a0c2d 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -44,13 +44,19 @@ * @crypto: the crypto configuration (ciphers, keys, etc..) * @dst_cache: cache for dst_entry used to send to peer * @bind: remote peer binding + * @keepalive_interval: seconds after which a new keepalive should be sent + * @keepalive_xmit_exp: future timestamp when next keepalive should be sent + * @last_sent: timestamp of the last successfully sent packet + * @keepalive_timeout: seconds after which an inactive peer is considered dead + * @keepalive_recv_exp: future timestamp when the peer should expire + * @last_recv: timestamp of the last authenticated received packet * @vpn_stats: per-peer in-VPN TX/RX stays * @link_stats: per-peer link/transport TX/RX stats * @delete_reason: why peer was deleted (i.e. timeout, transport error, ..) - * @lock: protects binding to peer (bind) + * @lock: protects binding to peer (bind) and keepalive* fields * @refcount: reference counter * @rcu: used to free peer in an RCU safe way - * @delete_work: deferred cleanup work, used to notify userspace + * @keepalive_work: used to schedule keepalive sending */ struct ovpn_peer { struct ovpn_priv *ovpn; @@ -92,13 +98,19 @@ struct ovpn_peer { struct ovpn_crypto_state crypto; struct dst_cache dst_cache; struct ovpn_bind __rcu *bind; + unsigned long keepalive_interval; + unsigned long keepalive_xmit_exp; + time64_t last_sent; + unsigned long keepalive_timeout; + unsigned long keepalive_recv_exp; + time64_t last_recv; struct ovpn_peer_stats vpn_stats; struct ovpn_peer_stats link_stats; enum ovpn_del_peer_reason delete_reason; - spinlock_t lock; /* protects bind */ + spinlock_t lock; /* protects bind and keepalive* */ struct kref refcount; struct rcu_head rcu; - struct work_struct delete_work; + struct work_struct keepalive_work; };

/** @@ -138,4 +150,7 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn, bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb, struct ovpn_peer *peer);

+void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout); +void ovpn_peer_keepalive_work(struct work_struct *work); + #endif /* _NET_OVPN_OVPNPEER_H_ */

A peer connected via UDP may change its IP address without reconnecting (float).

Add support for detecting and updating the new peer IP/port in case of floating.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/bind.c | 9 +- drivers/net/ovpn/io.c | 4 + drivers/net/ovpn/peer.c | 243 ++++++++++++++++++++++++++++++++++++------------ drivers/net/ovpn/peer.h | 3 +- 4 files changed, 193 insertions(+), 66 deletions(-)

diff --git a/drivers/net/ovpn/bind.c b/drivers/net/ovpn/bind.c index b4d2ccec2ceddf43bc445b489cc62a578ef0ad0a..c8ca340cca936a357409e9458807f27831511975 100644 --- a/drivers/net/ovpn/bind.c +++ b/drivers/net/ovpn/bind.c @@ -48,11 +48,8 @@ struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *ss) */ void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *new) { - struct ovpn_bind *old; + lockdep_assert_held(&peer->lock);

- spin_lock_bh(&peer->lock); - old = rcu_replace_pointer(peer->bind, new, true); - spin_unlock_bh(&peer->lock); - - kfree_rcu(old, rcu); + kfree_rcu(rcu_replace_pointer(peer->bind, new, + lockdep_is_held(&peer->lock)), rcu); } diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 0bab35fab06b4399c57e49732453df2fc12e9334..8162b12f7a36b897d685c70f1befd87d774826a1 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -134,6 +134,10 @@ void ovpn_decrypt_post(void *data, int ret) /* keep track of last received authenticated packet for keepalive */ WRITE_ONCE(peer->last_recv, ktime_get_real_seconds());

+ if (peer->sock->sock->sk->sk_protocol == IPPROTO_UDP) + /* check if this peer changed local or remote endpoint */ + ovpn_peer_endpoints_update(peer, skb); + /* point to encapsulated IP packet */ __skb_pull(skb, payload_offset);

diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index bcc7ffdd7a02774999f96b50232d18bf9db72280..3a794750a226b4e1bd0b683d5910b03d250cfb47 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -107,6 +107,191 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id) return peer; }

+/** + * ovpn_peer_reset_sockaddr - recreate binding for peer + * @peer: peer to recreate the binding for + * @ss: sockaddr to use as remote endpoint for the binding + * @local_ip: local IP for the binding + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_peer_reset_sockaddr(struct ovpn_peer *peer, + const struct sockaddr_storage *ss, + const u8 *local_ip) +{ + struct ovpn_bind *bind; + size_t ip_len; + + lockdep_assert_held(&peer->lock); + + /* create new ovpn_bind object */ + bind = ovpn_bind_from_sockaddr(ss); + if (IS_ERR(bind)) + return PTR_ERR(bind); + + if (local_ip) { + if (ss->ss_family == AF_INET) { + ip_len = sizeof(struct in_addr); + } else if (ss->ss_family == AF_INET6) { + ip_len = sizeof(struct in6_addr); + } else { + net_dbg_ratelimited("%s: invalid family %u for remote endpoint for peer %u\n", + netdev_name(peer->ovpn->dev), + ss->ss_family, peer->id); + kfree(bind); + return -EINVAL; + } + + memcpy(&bind->local, local_ip, ip_len); + } + + /* set binding */ + ovpn_bind_reset(peer, bind); + + return 0; +} + +/* variable name __tbl2 needs to be different from __tbl1 + * in the macro below to avoid confusing clang + */ +#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \ + typeof(_tbl) *__tbl2 = &(_tbl); \ + jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \ +}) + +#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ + typeof(_tbl) *__tbl1 = &(_tbl); \ + &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\ +}) + +/** + * ovpn_peer_endpoints_update - update remote or local endpoint for peer + * @peer: peer to update the remote endpoint for + * @skb: incoming packet to retrieve the source/destination address from + */ +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb) +{ + struct hlist_nulls_head *nhead; + struct sockaddr_storage ss; + const u8 *local_ip = NULL; + struct sockaddr_in6 *sa6; + struct sockaddr_in *sa; + struct ovpn_bind *bind; + size_t salen = 0; + + spin_lock_bh(&peer->lock); + bind = rcu_dereference_protected(peer->bind, + lockdep_is_held(&peer->lock)); + if (unlikely(!bind)) + goto unlock; + + switch (skb->protocol) { + case htons(ETH_P_IP): + /* float check */ + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) { + if (bind->remote.in4.sin_family == AF_INET) + local_ip = (u8 *)&bind->local; + sa = (struct sockaddr_in *)&ss; + sa->sin_family = AF_INET; + sa->sin_addr.s_addr = ip_hdr(skb)->saddr; + sa->sin_port = udp_hdr(skb)->source; + salen = sizeof(*sa); + break; + } + + /* local endpoint update */ + if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) { + net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n", + netdev_name(peer->ovpn->dev), + peer->id, &bind->local.ipv4.s_addr, + &ip_hdr(skb)->daddr); + bind->local.ipv4.s_addr = ip_hdr(skb)->daddr; + } + break; + case htons(ETH_P_IPV6): + /* float check */ + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) { + if (bind->remote.in6.sin6_family == AF_INET6) + local_ip = (u8 *)&bind->local; + sa6 = (struct sockaddr_in6 *)&ss; + sa6->sin6_family = AF_INET6; + sa6->sin6_addr = ipv6_hdr(skb)->saddr; + sa6->sin6_port = udp_hdr(skb)->source; + sa6->sin6_scope_id = ipv6_iface_scope_id(&ipv6_hdr(skb)->saddr, + skb->skb_iif); + salen = sizeof(*sa6); + } + + /* local endpoint update */ + if (unlikely(!ipv6_addr_equal(&bind->local.ipv6, + &ipv6_hdr(skb)->daddr))) { + net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n", + netdev_name(peer->ovpn->dev), + peer->id, &bind->local.ipv6, + &ipv6_hdr(skb)->daddr); + bind->local.ipv6 = ipv6_hdr(skb)->daddr; + } + break; + default: + goto unlock; + } + + /* if the peer did not float, we can bail out now */ + if (likely(!salen)) + goto unlock; + + if (unlikely(ovpn_peer_reset_sockaddr(peer, + (struct sockaddr_storage *)&ss, + local_ip) < 0)) + goto unlock; + + net_dbg_ratelimited("%s: peer %d floated to %pIScp", + netdev_name(peer->ovpn->dev), peer->id, &ss); + + spin_unlock_bh(&peer->lock); + + /* rehashing is required only in MP mode as P2P has one peer + * only and thus there is no hashtable + */ + if (peer->ovpn->mode == OVPN_MODE_MP) { + spin_lock_bh(&peer->ovpn->lock); + spin_lock_bh(&peer->lock); + bind = rcu_dereference_protected(peer->bind, + lockdep_is_held(&peer->lock)); + if (unlikely(!bind)) { + spin_unlock_bh(&peer->lock); + spin_unlock_bh(&peer->ovpn->lock); + return; + } + + /* his function may be invoked concurrently, therefore another + * float may have happened in parallel: perform rehashing + * using the peer->bind->remote directly as key + */ + + switch (bind->remote.in4.sin_family) { + case AF_INET: + salen = sizeof(*sa); + break; + case AF_INET6: + salen = sizeof(*sa6); + break; + } + + /* remove old hashing */ + hlist_nulls_del_init_rcu(&peer->hash_entry_transp_addr); + /* re-add with new transport address */ + nhead = ovpn_get_hash_head(peer->ovpn->peers->by_transp_addr, + &bind->remote, salen); + hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead); + spin_unlock_bh(&peer->lock); + spin_unlock_bh(&peer->ovpn->lock); + } + return; +unlock: + spin_unlock_bh(&peer->lock); +} + /** * ovpn_peer_release_rcu - RCU callback performing last peer release steps * @head: RCU member of the ovpn_peer @@ -210,19 +395,6 @@ static struct in6_addr ovpn_nexthop_from_skb6(struct sk_buff *skb) return rt->rt6i_gateway; }

-/* variable name __tbl2 needs to be different from __tbl1 - * in the macro below to avoid confusing clang - */ -#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \ - typeof(_tbl) *__tbl2 = &(_tbl); \ - jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \ -}) - -#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ - typeof(_tbl) *__tbl1 = &(_tbl); \ - &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\ -}) - /** * ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address * @ovpn: the openvpn instance to search @@ -466,51 +638,6 @@ struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id) return peer; }

-/** - * ovpn_peer_update_local_endpoint - update local endpoint for peer - * @peer: peer to update the endpoint for - * @skb: incoming packet to retrieve the destination address (local) from - */ -void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer, - struct sk_buff *skb) -{ - struct ovpn_bind *bind; - - rcu_read_lock(); - bind = rcu_dereference(peer->bind); - if (unlikely(!bind)) - goto unlock; - - spin_lock_bh(&peer->lock); - switch (skb->protocol) { - case htons(ETH_P_IP): - if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) { - net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n", - netdev_name(peer->ovpn->dev), - peer->id, &bind->local.ipv4.s_addr, - &ip_hdr(skb)->daddr); - bind->local.ipv4.s_addr = ip_hdr(skb)->daddr; - } - break; - case htons(ETH_P_IPV6): - if (unlikely(!ipv6_addr_equal(&bind->local.ipv6, - &ipv6_hdr(skb)->daddr))) { - net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n", - netdev_name(peer->ovpn->dev), - peer->id, &bind->local.ipv6, - &ipv6_hdr(skb)->daddr); - bind->local.ipv6 = ipv6_hdr(skb)->daddr; - } - break; - default: - break; - } - spin_unlock_bh(&peer->lock); - -unlock: - rcu_read_unlock(); -} - /** * ovpn_peer_get_by_dst - Lookup peer to send skb to * @ovpn: the private data representing the current VPN session diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index d12fbced1252f84665b084f7a24b6d515bed833d..361068a0a40fd11cd4d3d347f83352ed3d46048e 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -153,7 +153,6 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb, void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout); void ovpn_peer_keepalive_work(struct work_struct *work);

-void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer, - struct sk_buff *skb); +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb);

#endif /* _NET_OVPN_OVPNPEER_H_ */

This change introduces the netlink commands needed to add, get, delete and swap keys for a specific peer.

Userspace is expected to use these commands to create, inspect (non sensitive data only), destroy and rotate session keys for a specific peer.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/crypto.c | 40 ++++++ drivers/net/ovpn/crypto.h | 4 + drivers/net/ovpn/crypto_aead.c | 17 +++ drivers/net/ovpn/crypto_aead.h | 2 + drivers/net/ovpn/netlink.c | 301 ++++++++++++++++++++++++++++++++++++++++- 5 files changed, 360 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ovpn/crypto.c b/drivers/net/ovpn/crypto.c index fabc19994ba34260753911ac7d3e50b643b9b89f..6fccd73c6cf7d2566d1b819cb6d5d7b2ea98e81d 100644 --- a/drivers/net/ovpn/crypto.c +++ b/drivers/net/ovpn/crypto.c @@ -150,3 +150,43 @@ void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs)

spin_unlock_bh(&cs->lock); } + +/** + * ovpn_crypto_config_get - populate keyconf object with non-sensible key data + * @cs: the crypto state to extract the key data from + * @slot: the specific slot to inspect + * @keyconf: the output object to populate + * + * Return: 0 on success or a negative error code otherwise + */ +int ovpn_crypto_config_get(struct ovpn_crypto_state *cs, + enum ovpn_key_slot slot, + struct ovpn_key_config *keyconf) +{ + struct ovpn_crypto_key_slot *ks; + int idx; + + switch (slot) { + case OVPN_KEY_SLOT_PRIMARY: + idx = cs->primary_idx; + break; + case OVPN_KEY_SLOT_SECONDARY: + idx = !cs->primary_idx; + break; + default: + return -EINVAL; + } + + rcu_read_lock(); + ks = rcu_dereference(cs->slots[idx]); + if (!ks) { + rcu_read_unlock(); + return -ENOENT; + } + + keyconf->cipher_alg = ovpn_aead_crypto_alg(ks); + keyconf->key_id = ks->key_id; + rcu_read_unlock(); + + return 0; +} diff --git a/drivers/net/ovpn/crypto.h b/drivers/net/ovpn/crypto.h index b1b77c38ffe68dc21079e3a5354cc0695caa9cf3..05ca312765a4551b3493dc6a27228e8ad48e99f6 100644 --- a/drivers/net/ovpn/crypto.h +++ b/drivers/net/ovpn/crypto.h @@ -136,4 +136,8 @@ void ovpn_crypto_state_release(struct ovpn_crypto_state *cs);

void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs);

+int ovpn_crypto_config_get(struct ovpn_crypto_state *cs, + enum ovpn_key_slot slot, + struct ovpn_key_config *keyconf); + #endif /* _NET_OVPN_OVPNCRYPTO_H_ */ diff --git a/drivers/net/ovpn/crypto_aead.c b/drivers/net/ovpn/crypto_aead.c index dade83aad09b2d79ad65152ce867a961aeec01bd..b48b4df271bdec37de2996d2b88ecf7766380525 100644 --- a/drivers/net/ovpn/crypto_aead.c +++ b/drivers/net/ovpn/crypto_aead.c @@ -364,3 +364,20 @@ ovpn_aead_crypto_key_slot_new(const struct ovpn_key_config *kc) ovpn_aead_crypto_key_slot_destroy(ks); return ERR_PTR(ret); } + +enum ovpn_cipher_alg ovpn_aead_crypto_alg(struct ovpn_crypto_key_slot *ks) +{ + const char *alg_name; + + if (!ks->encrypt) + return OVPN_CIPHER_ALG_NONE; + + alg_name = crypto_tfm_alg_name(crypto_aead_tfm(ks->encrypt)); + + if (!strcmp(alg_name, ALG_NAME_AES)) + return OVPN_CIPHER_ALG_AES_GCM; + else if (!strcmp(alg_name, ALG_NAME_CHACHAPOLY)) + return OVPN_CIPHER_ALG_CHACHA20_POLY1305; + else + return OVPN_CIPHER_ALG_NONE; +} diff --git a/drivers/net/ovpn/crypto_aead.h b/drivers/net/ovpn/crypto_aead.h index 77ee8141599bc06b0dc664c5b0a4dae660a89238..fb65be82436edd7ff89b171f7a89c9103b617d1f 100644 --- a/drivers/net/ovpn/crypto_aead.h +++ b/drivers/net/ovpn/crypto_aead.h @@ -28,4 +28,6 @@ struct ovpn_crypto_key_slot * ovpn_aead_crypto_key_slot_new(const struct ovpn_key_config *kc); void ovpn_aead_crypto_key_slot_destroy(struct ovpn_crypto_key_slot *ks);

+enum ovpn_cipher_alg ovpn_aead_crypto_alg(struct ovpn_crypto_key_slot *ks); + #endif /* _NET_OVPN_OVPNAEAD_H_ */ diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c index 9cc072a9e818dce97cc7dc1b48fb256a6039298f..f82057a4d1a9e6fd698698a4652d50c59d901bfa 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -17,6 +17,7 @@ #include "netlink.h" #include "netlink-gen.h" #include "bind.h" +#include "crypto.h" #include "peer.h" #include "socket.h"

@@ -740,24 +741,316 @@ int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info) return ret; }

+static int ovpn_nl_get_key_dir(struct genl_info *info, struct nlattr *key, + enum ovpn_cipher_alg cipher, + struct ovpn_key_direction *dir) +{ + struct nlattr *attrs[OVPN_A_KEYDIR_MAX + 1]; + int ret; + + ret = nla_parse_nested(attrs, OVPN_A_KEYDIR_MAX, key, + ovpn_keydir_nl_policy, info->extack); + if (ret) + return ret; + + switch (cipher) { + case OVPN_CIPHER_ALG_AES_GCM: + case OVPN_CIPHER_ALG_CHACHA20_POLY1305: + if (NL_REQ_ATTR_CHECK(info->extack, key, attrs, + OVPN_A_KEYDIR_CIPHER_KEY) || + NL_REQ_ATTR_CHECK(info->extack, key, attrs, + OVPN_A_KEYDIR_NONCE_TAIL)) + return -EINVAL; + + dir->cipher_key = nla_data(attrs[OVPN_A_KEYDIR_CIPHER_KEY]); + dir->cipher_key_size = nla_len(attrs[OVPN_A_KEYDIR_CIPHER_KEY]); + + /* These algorithms require a 96bit nonce, + * Construct it by combining 4-bytes packet id and + * 8-bytes nonce-tail from userspace + */ + dir->nonce_tail = nla_data(attrs[OVPN_A_KEYDIR_NONCE_TAIL]); + dir->nonce_tail_size = nla_len(attrs[OVPN_A_KEYDIR_NONCE_TAIL]); + break; + default: + NL_SET_ERR_MSG_MOD(info->extack, "unsupported cipher"); + return -EINVAL; + } + + return 0; +} + +/** + * ovpn_nl_key_new_doit - configure a new key for the specified peer + * @skb: incoming netlink message + * @info: genetlink metadata + * + * This function allows the user to install a new key in the peer crypto + * state. + * Each peer has two 'slots', namely 'primary' and 'secondary', where + * keys can be installed. The key in the 'primary' slot is used for + * encryption, while both keys can be used for decryption by matching the + * key ID carried in the incoming packet. + * + * The user is responsible for rotating keys when necessary. The user + * may fetch peer traffic statistics via netlink in order to better + * identify the right time to rotate keys. + * The renegotiation follows these steps: + * 1. a new key is computed by the user and is installed in the 'secondary' + * slot + * 2. at user discretion (usually after a predetermined time) 'primary' and + * 'secondary' contents are swapped and the new key starts being used for + * encryption, while the old key is kept around for decryption of late + * packets. + * + * Return: 0 on success or a negative error code otherwise. + */ int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info) { - return -EOPNOTSUPP; + struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1]; + struct ovpn_priv *ovpn = info->user_ptr[0]; + struct ovpn_peer_key_reset pkr; + struct ovpn_peer *peer; + u32 peer_id; + int ret; + + if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF)) + return -EINVAL; + + ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX, + info->attrs[OVPN_A_KEYCONF], + ovpn_keyconf_nl_policy, info->extack); + if (ret) + return ret; + + if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_PEER_ID)) + return -EINVAL; + + if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_SLOT) || + NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_KEY_ID) || + NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_CIPHER_ALG) || + NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_ENCRYPT_DIR) || + NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_DECRYPT_DIR)) + return -EINVAL; + + pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]); + pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]); + pkr.key.cipher_alg = nla_get_u16(attrs[OVPN_A_KEYCONF_CIPHER_ALG]); + + ret = ovpn_nl_get_key_dir(info, attrs[OVPN_A_KEYCONF_ENCRYPT_DIR], + pkr.key.cipher_alg, &pkr.key.encrypt); + if (ret < 0) + return ret; + + ret = ovpn_nl_get_key_dir(info, attrs[OVPN_A_KEYCONF_DECRYPT_DIR], + pkr.key.cipher_alg, &pkr.key.decrypt); + if (ret < 0) + return ret; + + peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]); + peer = ovpn_peer_get_by_id(ovpn, peer_id); + if (!peer) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "no peer with id %u to set key for", + peer_id); + return -ENOENT; + } + + ret = ovpn_crypto_state_reset(&peer->crypto, &pkr); + if (ret < 0) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "cannot install new key for peer %u", + peer_id); + goto out; + } + + netdev_dbg(ovpn->dev, "new key installed (id=%u) for peer %u\n", + pkr.key.key_id, peer_id); +out: + ovpn_peer_put(peer); + return ret; +} + +static int ovpn_nl_send_key(struct sk_buff *skb, const struct genl_info *info, + u32 peer_id, enum ovpn_key_slot slot, + const struct ovpn_key_config *keyconf) +{ + struct nlattr *attr; + void *hdr; + + hdr = genlmsg_put(skb, info->snd_portid, info->snd_seq, &ovpn_nl_family, + 0, OVPN_CMD_KEY_GET); + if (!hdr) + return -ENOBUFS; + + attr = nla_nest_start(skb, OVPN_A_KEYCONF); + if (!attr) + goto err; + + if (nla_put_u32(skb, OVPN_A_KEYCONF_PEER_ID, peer_id)) + goto err; + + if (nla_put_u32(skb, OVPN_A_KEYCONF_SLOT, slot) || + nla_put_u32(skb, OVPN_A_KEYCONF_KEY_ID, keyconf->key_id) || + nla_put_u32(skb, OVPN_A_KEYCONF_CIPHER_ALG, keyconf->cipher_alg)) + goto err; + + nla_nest_end(skb, attr); + genlmsg_end(skb, hdr); + + return 0; +err: + genlmsg_cancel(skb, hdr); + return -EMSGSIZE; }

int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info) { - return -EOPNOTSUPP; + struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1]; + struct ovpn_priv *ovpn = info->user_ptr[0]; + struct ovpn_key_config keyconf = { 0 }; + enum ovpn_key_slot slot; + struct ovpn_peer *peer; + struct sk_buff *msg; + u32 peer_id; + int ret; + + if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF)) + return -EINVAL; + + ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX, + info->attrs[OVPN_A_KEYCONF], + ovpn_keyconf_nl_policy, info->extack); + if (ret) + return ret; + + if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_PEER_ID)) + return -EINVAL; + + if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_SLOT)) + return -EINVAL; + + peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]); + peer = ovpn_peer_get_by_id(ovpn, peer_id); + if (!peer) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "cannot find peer with id %u", peer_id); + return -ENOENT; + } + + slot = nla_get_u32(attrs[OVPN_A_KEYCONF_SLOT]); + + ret = ovpn_crypto_config_get(&peer->crypto, slot, &keyconf); + if (ret < 0) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "cannot extract key from slot %u for peer %u", + slot, peer_id); + goto err; + } + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) { + ret = -ENOMEM; + goto err; + } + + ret = ovpn_nl_send_key(msg, info, peer->id, slot, &keyconf); + if (ret < 0) { + nlmsg_free(msg); + goto err; + } + + ret = genlmsg_reply(msg, info); +err: + ovpn_peer_put(peer); + return ret; }

int ovpn_nl_key_swap_doit(struct sk_buff *skb, struct genl_info *info) { - return -EOPNOTSUPP; + struct ovpn_priv *ovpn = info->user_ptr[0]; + struct nlattr *attrs[OVPN_A_PEER_MAX + 1]; + struct ovpn_peer *peer; + u32 peer_id; + int ret; + + if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF)) + return -EINVAL; + + ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX, + info->attrs[OVPN_A_KEYCONF], + ovpn_keyconf_nl_policy, info->extack); + if (ret) + return ret; + + if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_PEER_ID)) + return -EINVAL; + + peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]); + peer = ovpn_peer_get_by_id(ovpn, peer_id); + if (!peer) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "no peer with id %u to swap keys for", + peer_id); + return -ENOENT; + } + + ovpn_crypto_key_slots_swap(&peer->crypto); + ovpn_peer_put(peer); + + return 0; }

int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info) { - return -EOPNOTSUPP; + struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1]; + struct ovpn_priv *ovpn = info->user_ptr[0]; + enum ovpn_key_slot slot; + struct ovpn_peer *peer; + u32 peer_id; + int ret; + + if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF)) + return -EINVAL; + + ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX, + info->attrs[OVPN_A_KEYCONF], + ovpn_keyconf_nl_policy, info->extack); + if (ret) + return ret; + + if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_PEER_ID)) + return -EINVAL; + + if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_SLOT)) + return -EINVAL; + + peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]); + slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]); + + peer = ovpn_peer_get_by_id(ovpn, peer_id); + if (!peer) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "no peer with id %u to delete key for", + peer_id); + return -ENOENT; + } + + ovpn_crypto_key_slot_delete(&peer->crypto, slot); + ovpn_peer_put(peer); + + return 0; }

/**

Whenever a peer is deleted, send a notification to userspace so that it can react accordingly.

This is most important when a peer is deleted due to ping timeout, because it all happens in kernelspace and thus userspace has no direct way to learn about it.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/netlink.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/netlink.h | 1 + drivers/net/ovpn/peer.c | 1 + 3 files changed, 57 insertions(+)

diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c index 0e68f023e95e6dcb41d07f960ea032292b28d0af..5b6a3566e5cd287720ae16a963c7623c06ff4add 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -1053,6 +1053,61 @@ int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info) return 0; }

+/** + * ovpn_nl_peer_del_notify - notify userspace about peer being deleted + * @peer: the peer being deleted + * + * Return: 0 on success or a negative error code otherwise + */ +int ovpn_nl_peer_del_notify(struct ovpn_peer *peer) +{ + struct sk_buff *msg; + struct nlattr *attr; + int ret = -EMSGSIZE; + void *hdr; + + netdev_info(peer->ovpn->dev, "deleting peer with id %u, reason %d\n", + peer->id, peer->delete_reason); + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); + if (!msg) + return -ENOMEM; + + hdr = genlmsg_put(msg, 0, 0, &ovpn_nl_family, 0, OVPN_CMD_PEER_DEL_NTF); + if (!hdr) { + ret = -ENOBUFS; + goto err_free_msg; + } + + if (nla_put_u32(msg, OVPN_A_IFINDEX, peer->ovpn->dev->ifindex)) + goto err_cancel_msg; + + attr = nla_nest_start(msg, OVPN_A_PEER); + if (!attr) + goto err_cancel_msg; + + if (nla_put_u8(msg, OVPN_A_PEER_DEL_REASON, peer->delete_reason)) + goto err_cancel_msg; + + if (nla_put_u32(msg, OVPN_A_PEER_ID, peer->id)) + goto err_cancel_msg; + + nla_nest_end(msg, attr); + + genlmsg_end(msg, hdr); + + genlmsg_multicast_netns(&ovpn_nl_family, sock_net(peer->sock->sock->sk), + msg, 0, OVPN_NLGRP_PEERS, GFP_KERNEL); + + return 0; + +err_cancel_msg: + genlmsg_cancel(msg, hdr); +err_free_msg: + nlmsg_free(msg); + return ret; +} + /** * ovpn_nl_key_swap_notify - notify userspace peer's key must be renewed * @peer: the peer whose key needs to be renewed diff --git a/drivers/net/ovpn/netlink.h b/drivers/net/ovpn/netlink.h index 33390b13c8904d40b629662005a9eb92ff617c3b..4ab3abcf23dba11f6b92e3d69e700693adbc671b 100644 --- a/drivers/net/ovpn/netlink.h +++ b/drivers/net/ovpn/netlink.h @@ -12,6 +12,7 @@ int ovpn_nl_register(void); void ovpn_nl_unregister(void);

+int ovpn_nl_peer_del_notify(struct ovpn_peer *peer); int ovpn_nl_key_swap_notify(struct ovpn_peer *peer, u8 key_id);

#endif /* _NET_OVPN_NETLINK_H_ */ diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index ed450be2d2379664a7fe0f17a9af527829474174..7e0de795b389e85e49bcae19d906e7a57ef31690 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -995,6 +995,7 @@ static void ovpn_peer_remove(struct ovpn_peer *peer, }

peer->delete_reason = reason; + ovpn_nl_peer_del_notify(peer); if (peer->sock) ovpn_socket_put(peer->sock);

The ovpn-cli tool can be compiled and used as selftest for the ovpn kernel module.

[NOTE: it depends on libmedtls for decoding base64-encoded keys]

ovpn-cli implements the netlink and RTNL APIs and can thus be integrated in any script for more automated testing.

Along with the tool, 4 scripts are provided that perform basic functionality tests by means of network namespaces. These scripts take part to the kselftest automation.

The output of the scripts, which will appear in the kselftest reports, is a list of steps performed by the scripts plus some output coming from the execution of `ping`, `iperf` and `ovpn-cli` itself. In general it is useful only in case of failure, in order to understand which step has failed and why.

Cc: linux-kselftest@vger.kernel.org Signed-off-by: Antonio Quartulli antonio@openvpn.net Reviewed-by: Shuah Khan skhan@linuxfoundation.org --- MAINTAINERS | 1 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/net/ovpn/.gitignore | 2 + tools/testing/selftests/net/ovpn/Makefile | 17 + tools/testing/selftests/net/ovpn/config | 10 + tools/testing/selftests/net/ovpn/data64.key | 5 + tools/testing/selftests/net/ovpn/ovpn-cli.c | 2366 ++++++++++++++++++++ tools/testing/selftests/net/ovpn/tcp_peers.txt | 5 + .../testing/selftests/net/ovpn/test-chachapoly.sh | 9 + tools/testing/selftests/net/ovpn/test-float.sh | 9 + tools/testing/selftests/net/ovpn/test-tcp.sh | 9 + tools/testing/selftests/net/ovpn/test.sh | 182 ++ tools/testing/selftests/net/ovpn/udp_peers.txt | 5 + 13 files changed, 2621 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS index 726da67bb550f8882215f08f784c071283760f3a..4c7110b3955690350693ce65e28f8b2b913d5d02 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17564,6 +17564,7 @@ T: git https://github.com/OpenVPN/linux-kernel-ovpn.git F: Documentation/netlink/specs/ovpn.yaml F: drivers/net/ovpn/ F: include/uapi/linux/ovpn.h +F: tools/testing/selftests/net/ovpn/

OPENVSWITCH M: Pravin B Shelar pshelar@ovn.org diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 2401e973c35963c415c1041bc622f06c8a7ec251..e8363c21074c5f4f1cf4140369e7e1c15ec470bf 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -68,6 +68,7 @@ TARGETS += net/hsr TARGETS += net/mptcp TARGETS += net/netfilter TARGETS += net/openvswitch +TARGETS += net/ovpn TARGETS += net/packetdrill TARGETS += net/rds TARGETS += net/tcp_ao diff --git a/tools/testing/selftests/net/ovpn/.gitignore b/tools/testing/selftests/net/ovpn/.gitignore new file mode 100644 index 0000000000000000000000000000000000000000..ee44c081ca7c089933659689303c303a9fa9713b --- /dev/null +++ b/tools/testing/selftests/net/ovpn/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0+ +ovpn-cli diff --git a/tools/testing/selftests/net/ovpn/Makefile b/tools/testing/selftests/net/ovpn/Makefile new file mode 100644 index 0000000000000000000000000000000000000000..c76d8fd953c5674941c8c2787813063b1bce180f --- /dev/null +++ b/tools/testing/selftests/net/ovpn/Makefile @@ -0,0 +1,17 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020-2024 OpenVPN, Inc. +# +CFLAGS = -pedantic -Wextra -Wall -Wl,--no-as-needed -g -O0 -ggdb $(KHDR_INCLUDES) +CFLAGS += $(shell pkg-config --cflags libnl-3.0 libnl-genl-3.0) + +LDFLAGS = -lmbedtls -lmbedcrypto +LDFLAGS += $(shell pkg-config --libs libnl-3.0 libnl-genl-3.0) + +TEST_PROGS = test.sh \ + test-chachapoly.sh \ + test-tcp.sh \ + test-float.sh + +TEST_GEN_FILES = ovpn-cli + +include ../../lib.mk diff --git a/tools/testing/selftests/net/ovpn/config b/tools/testing/selftests/net/ovpn/config new file mode 100644 index 0000000000000000000000000000000000000000..71946ba9fa175c191725e369eb9b973503d9d9c4 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/config @@ -0,0 +1,10 @@ +CONFIG_NET=y +CONFIG_INET=y +CONFIG_STREAM_PARSER=y +CONFIG_NET_UDP_TUNNEL=y +CONFIG_DST_CACHE=y +CONFIG_CRYPTO=y +CONFIG_CRYPTO_AES=y +CONFIG_CRYPTO_GCM=y +CONFIG_CRYPTO_CHACHA20POLY1305=y +CONFIG_OVPN=m diff --git a/tools/testing/selftests/net/ovpn/data64.key b/tools/testing/selftests/net/ovpn/data64.key new file mode 100644 index 0000000000000000000000000000000000000000..a99e88c4e290f58b12f399b857b873f308d9ba09 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/data64.key @@ -0,0 +1,5 @@ +jRqMACN7d7/aFQNT8S7jkrBD8uwrgHbG5OQZP2eu4R1Y7tfpS2bf5RHv06Vi163CGoaIiTX99R3B +ia9ycAH8Wz1+9PWv51dnBLur9jbShlgZ2QHLtUc4a/gfT7zZwULXuuxdLnvR21DDeMBaTbkgbai9 +uvAa7ne1liIgGFzbv+Bas4HDVrygxIxuAnP5Qgc3648IJkZ0QEXPF+O9f0n5+QIvGCxkAUVx+5K6 +KIs+SoeWXnAopELmoGSjUpFtJbagXK82HfdqpuUxT2Tnuef0/14SzVE/vNleBNu2ZbyrSAaah8tE +BofkPJUBFY+YQcfZNM5Dgrw3i+Bpmpq/gpdg5w== diff --git a/tools/testing/selftests/net/ovpn/ovpn-cli.c b/tools/testing/selftests/net/ovpn/ovpn-cli.c new file mode 100644 index 0000000000000000000000000000000000000000..7686801516337a5bbbe6b6bb2f31b8071fb4dc01 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c @@ -0,0 +1,2366 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel accelerator + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#include <stdio.h> +#include <inttypes.h> +#include <stdbool.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <arpa/inet.h> +#include <net/if.h> +#include <netinet/in.h> +#include <time.h> + +#include <linux/ovpn.h> +#include <linux/types.h> +#include <linux/netlink.h> + +#include <netlink/socket.h> +#include <netlink/netlink.h> +#include <netlink/genl/genl.h> +#include <netlink/genl/family.h> +#include <netlink/genl/ctrl.h> + +#include <mbedtls/base64.h> +#include <mbedtls/error.h> + +#include <sys/socket.h> + +/* defines to make checkpatch happy */ +#define strscpy strncpy +#define __always_unused __attribute__((__unused__)) + +/* libnl < 3.5.0 does not set the NLA_F_NESTED on its own, therefore we + * have to explicitly do it to prevent the kernel from failing upon + * parsing of the message + */ +#define nla_nest_start(_msg, _type) \ + nla_nest_start(_msg, (_type) | NLA_F_NESTED) + +uint64_t nla_get_uint(struct nlattr *attr) +{ + if (nla_len(attr) == sizeof(uint32_t)) + return nla_get_u32(attr); + else + return nla_get_u64(attr); +} + +typedef int (*ovpn_nl_cb)(struct nl_msg *msg, void *arg); + +enum ovpn_key_direction { + KEY_DIR_IN = 0, + KEY_DIR_OUT, +}; + +#define KEY_LEN (256 / 8) +#define NONCE_LEN 8 + +#define PEER_ID_UNDEF 0x00FFFFFF + +struct nl_ctx { + struct nl_sock *nl_sock; + struct nl_msg *nl_msg; + struct nl_cb *nl_cb; + + int ovpn_dco_id; +}; + +enum ovpn_cmd { + CMD_INVALID, + CMD_NEW_IFACE, + CMD_DEL_IFACE, + CMD_LISTEN, + CMD_CONNECT, + CMD_NEW_PEER, + CMD_NEW_MULTI_PEER, + CMD_SET_PEER, + CMD_DEL_PEER, + CMD_GET_PEER, + CMD_NEW_KEY, + CMD_DEL_KEY, + CMD_GET_KEY, + CMD_SWAP_KEYS, + CMD_LISTEN_MCAST, +}; + +struct ovpn_ctx { + enum ovpn_cmd cmd; + + __u8 key_enc[KEY_LEN]; + __u8 key_dec[KEY_LEN]; + __u8 nonce[NONCE_LEN]; + + enum ovpn_cipher_alg cipher; + + sa_family_t sa_family; + + unsigned long peer_id; + unsigned long lport; + + union { + struct sockaddr_in in4; + struct sockaddr_in6 in6; + } remote; + + union { + struct sockaddr_in in4; + struct sockaddr_in6 in6; + } peer_ip; + + bool peer_ip_set; + + unsigned int ifindex; + char ifname[IFNAMSIZ]; + enum ovpn_mode mode; + bool mode_set; + + int socket; + int cli_socket; + + __u32 keepalive_interval; + __u32 keepalive_timeout; + + enum ovpn_key_direction key_dir; + enum ovpn_key_slot key_slot; + int key_id; + + const char *peers_file; +}; + +static int ovpn_nl_recvmsgs(struct nl_ctx *ctx) +{ + int ret; + + ret = nl_recvmsgs(ctx->nl_sock, ctx->nl_cb); + + switch (ret) { + case -NLE_INTR: + fprintf(stderr, + "netlink received interrupt due to signal - ignoring\n"); + break; + case -NLE_NOMEM: + fprintf(stderr, "netlink out of memory error\n"); + break; + case -NLE_AGAIN: + fprintf(stderr, + "netlink reports blocking read - aborting wait\n"); + break; + default: + if (ret) + fprintf(stderr, "netlink reports error (%d): %s\n", + ret, nl_geterror(-ret)); + break; + } + + return ret; +} + +static struct nl_ctx *nl_ctx_alloc_flags(struct ovpn_ctx *ovpn, int cmd, + int flags) +{ + struct nl_ctx *ctx; + int err, ret; + + ctx = calloc(1, sizeof(*ctx)); + if (!ctx) + return NULL; + + ctx->nl_sock = nl_socket_alloc(); + if (!ctx->nl_sock) { + fprintf(stderr, "cannot allocate netlink socket\n"); + goto err_free; + } + + nl_socket_set_buffer_size(ctx->nl_sock, 8192, 8192); + + ret = genl_connect(ctx->nl_sock); + if (ret) { + fprintf(stderr, "cannot connect to generic netlink: %s\n", + nl_geterror(ret)); + goto err_sock; + } + + /* enable Extended ACK for detailed error reporting */ + err = 1; + setsockopt(nl_socket_get_fd(ctx->nl_sock), SOL_NETLINK, NETLINK_EXT_ACK, + &err, sizeof(err)); + + ctx->ovpn_dco_id = genl_ctrl_resolve(ctx->nl_sock, OVPN_FAMILY_NAME); + if (ctx->ovpn_dco_id < 0) { + fprintf(stderr, "cannot find ovpn_dco netlink component: %d\n", + ctx->ovpn_dco_id); + goto err_free; + } + + ctx->nl_msg = nlmsg_alloc(); + if (!ctx->nl_msg) { + fprintf(stderr, "cannot allocate netlink message\n"); + goto err_sock; + } + + ctx->nl_cb = nl_cb_alloc(NL_CB_DEFAULT); + if (!ctx->nl_cb) { + fprintf(stderr, "failed to allocate netlink callback\n"); + goto err_msg; + } + + nl_socket_set_cb(ctx->nl_sock, ctx->nl_cb); + + genlmsg_put(ctx->nl_msg, 0, 0, ctx->ovpn_dco_id, 0, flags, cmd, 0); + + if (ovpn->ifindex > 0) + NLA_PUT_U32(ctx->nl_msg, OVPN_A_IFINDEX, ovpn->ifindex); + + return ctx; +nla_put_failure: +err_msg: + nlmsg_free(ctx->nl_msg); +err_sock: + nl_socket_free(ctx->nl_sock); +err_free: + free(ctx); + return NULL; +} + +static struct nl_ctx *nl_ctx_alloc(struct ovpn_ctx *ovpn, int cmd) +{ + return nl_ctx_alloc_flags(ovpn, cmd, 0); +} + +static void nl_ctx_free(struct nl_ctx *ctx) +{ + if (!ctx) + return; + + nl_socket_free(ctx->nl_sock); + nlmsg_free(ctx->nl_msg); + nl_cb_put(ctx->nl_cb); + free(ctx); +} + +static int ovpn_nl_cb_error(struct sockaddr_nl (*nla)__always_unused, + struct nlmsgerr *err, void *arg) +{ + struct nlmsghdr *nlh = (struct nlmsghdr *)err - 1; + struct nlattr *tb_msg[NLMSGERR_ATTR_MAX + 1]; + int len = nlh->nlmsg_len; + struct nlattr *attrs; + int *ret = arg; + int ack_len = sizeof(*nlh) + sizeof(int) + sizeof(*nlh); + + *ret = err->error; + + if (!(nlh->nlmsg_flags & NLM_F_ACK_TLVS)) + return NL_STOP; + + if (!(nlh->nlmsg_flags & NLM_F_CAPPED)) + ack_len += err->msg.nlmsg_len - sizeof(*nlh); + + if (len <= ack_len) + return NL_STOP; + + attrs = (void *)((uint8_t *)nlh + ack_len); + len -= ack_len; + + nla_parse(tb_msg, NLMSGERR_ATTR_MAX, attrs, len, NULL); + if (tb_msg[NLMSGERR_ATTR_MSG]) { + len = strnlen((char *)nla_data(tb_msg[NLMSGERR_ATTR_MSG]), + nla_len(tb_msg[NLMSGERR_ATTR_MSG])); + fprintf(stderr, "kernel error: %*s\n", len, + (char *)nla_data(tb_msg[NLMSGERR_ATTR_MSG])); + } + + if (tb_msg[NLMSGERR_ATTR_MISS_NEST]) { + fprintf(stderr, "missing required nesting type %u\n", + nla_get_u32(tb_msg[NLMSGERR_ATTR_MISS_NEST])); + } + + if (tb_msg[NLMSGERR_ATTR_MISS_TYPE]) { + fprintf(stderr, "missing required attribute type %u\n", + nla_get_u32(tb_msg[NLMSGERR_ATTR_MISS_TYPE])); + } + + return NL_STOP; +} + +static int ovpn_nl_cb_finish(struct nl_msg (*msg)__always_unused, + void *arg) +{ + int *status = arg; + + *status = 0; + return NL_SKIP; +} + +static int ovpn_nl_cb_ack(struct nl_msg (*msg)__always_unused, + void *arg) +{ + int *status = arg; + + *status = 0; + return NL_STOP; +} + +static int ovpn_nl_msg_send(struct nl_ctx *ctx, ovpn_nl_cb cb) +{ + int status = 1; + + nl_cb_err(ctx->nl_cb, NL_CB_CUSTOM, ovpn_nl_cb_error, &status); + nl_cb_set(ctx->nl_cb, NL_CB_FINISH, NL_CB_CUSTOM, ovpn_nl_cb_finish, + &status); + nl_cb_set(ctx->nl_cb, NL_CB_ACK, NL_CB_CUSTOM, ovpn_nl_cb_ack, &status); + + if (cb) + nl_cb_set(ctx->nl_cb, NL_CB_VALID, NL_CB_CUSTOM, cb, ctx); + + nl_send_auto_complete(ctx->nl_sock, ctx->nl_msg); + + while (status == 1) + ovpn_nl_recvmsgs(ctx); + + if (status < 0) + fprintf(stderr, "failed to send netlink message: %s (%d)\n", + strerror(-status), status); + + return status; +} + +static int ovpn_parse_key(const char *file, struct ovpn_ctx *ctx) +{ + int idx_enc, idx_dec, ret = -1; + unsigned char *ckey = NULL; + __u8 *bkey = NULL; + size_t olen = 0; + long ckey_len; + FILE *fp; + + fp = fopen(file, "r"); + if (!fp) { + fprintf(stderr, "cannot open: %s\n", file); + return -1; + } + + /* get file size */ + fseek(fp, 0L, SEEK_END); + ckey_len = ftell(fp); + rewind(fp); + + /* if the file is longer, let's just read a portion */ + if (ckey_len > 256) + ckey_len = 256; + + ckey = malloc(ckey_len); + if (!ckey) + goto err; + + ret = fread(ckey, 1, ckey_len, fp); + if (ret != ckey_len) { + fprintf(stderr, + "couldn't read enough data from key file: %dbytes read\n", + ret); + goto err; + } + + olen = 0; + ret = mbedtls_base64_decode(NULL, 0, &olen, ckey, ckey_len); + if (ret != MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL) { + char buf[256]; + + mbedtls_strerror(ret, buf, sizeof(buf)); + fprintf(stderr, "unexpected base64 error1: %s (%d)\n", buf, + ret); + + goto err; + } + + bkey = malloc(olen); + if (!bkey) { + fprintf(stderr, "cannot allocate binary key buffer\n"); + goto err; + } + + ret = mbedtls_base64_decode(bkey, olen, &olen, ckey, ckey_len); + if (ret) { + char buf[256]; + + mbedtls_strerror(ret, buf, sizeof(buf)); + fprintf(stderr, "unexpected base64 error2: %s (%d)\n", buf, + ret); + + goto err; + } + + if (olen < 2 * KEY_LEN + NONCE_LEN) { + fprintf(stderr, + "not enough data in key file, found %zdB but needs %dB\n", + olen, 2 * KEY_LEN + NONCE_LEN); + goto err; + } + + switch (ctx->key_dir) { + case KEY_DIR_IN: + idx_enc = 0; + idx_dec = 1; + break; + case KEY_DIR_OUT: + idx_enc = 1; + idx_dec = 0; + break; + default: + goto err; + } + + memcpy(ctx->key_enc, bkey + KEY_LEN * idx_enc, KEY_LEN); + memcpy(ctx->key_dec, bkey + KEY_LEN * idx_dec, KEY_LEN); + memcpy(ctx->nonce, bkey + 2 * KEY_LEN, NONCE_LEN); + + ret = 0; + +err: + fclose(fp); + free(bkey); + free(ckey); + + return ret; +} + +static int ovpn_parse_cipher(const char *cipher, struct ovpn_ctx *ctx) +{ + if (strcmp(cipher, "aes") == 0) + ctx->cipher = OVPN_CIPHER_ALG_AES_GCM; + else if (strcmp(cipher, "chachapoly") == 0) + ctx->cipher = OVPN_CIPHER_ALG_CHACHA20_POLY1305; + else if (strcmp(cipher, "none") == 0) + ctx->cipher = OVPN_CIPHER_ALG_NONE; + else + return -ENOTSUP; + + return 0; +} + +static int ovpn_parse_key_direction(const char *dir, struct ovpn_ctx *ctx) +{ + int in_dir; + + in_dir = strtoll(dir, NULL, 10); + switch (in_dir) { + case KEY_DIR_IN: + case KEY_DIR_OUT: + ctx->key_dir = in_dir; + break; + default: + fprintf(stderr, + "invalid key direction provided. Can be 0 or 1 only\n"); + return -1; + } + + return 0; +} + +static int ovpn_socket(struct ovpn_ctx *ctx, sa_family_t family, int proto) +{ + struct sockaddr_storage local_sock = { 0 }; + struct sockaddr_in6 *in6; + struct sockaddr_in *in; + int ret, s, sock_type; + size_t sock_len; + + if (proto == IPPROTO_UDP) + sock_type = SOCK_DGRAM; + else if (proto == IPPROTO_TCP) + sock_type = SOCK_STREAM; + else + return -EINVAL; + + s = socket(family, sock_type, 0); + if (s < 0) { + perror("cannot create socket"); + return -1; + } + + switch (family) { + case AF_INET: + in = (struct sockaddr_in *)&local_sock; + in->sin_family = family; + in->sin_port = htons(ctx->lport); + in->sin_addr.s_addr = htonl(INADDR_ANY); + sock_len = sizeof(*in); + break; + case AF_INET6: + in6 = (struct sockaddr_in6 *)&local_sock; + in6->sin6_family = family; + in6->sin6_port = htons(ctx->lport); + in6->sin6_addr = in6addr_any; + sock_len = sizeof(*in6); + break; + default: + return -1; + } + + int opt = 1; + + ret = setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)); + + if (ret < 0) { + perror("setsockopt for SO_REUSEADDR"); + return ret; + } + + ret = setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(opt)); + if (ret < 0) { + perror("setsockopt for SO_REUSEPORT"); + return ret; + } + + if (family == AF_INET6) { + opt = 0; + if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &opt, + sizeof(opt))) { + perror("failed to set IPV6_V6ONLY"); + return -1; + } + } + + ret = bind(s, (struct sockaddr *)&local_sock, sock_len); + if (ret < 0) { + perror("cannot bind socket"); + goto err_socket; + } + + ctx->socket = s; + ctx->sa_family = family; + return 0; + +err_socket: + close(s); + return -1; +} + +static int ovpn_udp_socket(struct ovpn_ctx *ctx, sa_family_t family) +{ + return ovpn_socket(ctx, family, IPPROTO_UDP); +} + +static int ovpn_listen(struct ovpn_ctx *ctx, sa_family_t family) +{ + int ret; + + ret = ovpn_socket(ctx, family, IPPROTO_TCP); + if (ret < 0) + return ret; + + ret = listen(ctx->socket, 10); + if (ret < 0) { + perror("listen"); + close(ctx->socket); + return -1; + } + + return 0; +} + +static int ovpn_accept(struct ovpn_ctx *ctx) +{ + socklen_t socklen; + int ret; + + socklen = sizeof(ctx->remote); + ret = accept(ctx->socket, (struct sockaddr *)&ctx->remote, &socklen); + if (ret < 0) { + perror("accept"); + goto err; + } + + fprintf(stderr, "Connection received!\n"); + + switch (socklen) { + case sizeof(struct sockaddr_in): + case sizeof(struct sockaddr_in6): + break; + default: + fprintf(stderr, "error: expecting IPv4 or IPv6 connection\n"); + close(ret); + ret = -EINVAL; + goto err; + } + + return ret; +err: + close(ctx->socket); + return ret; +} + +static int ovpn_connect(struct ovpn_ctx *ovpn) +{ + socklen_t socklen; + int s, ret; + + s = socket(ovpn->remote.in4.sin_family, SOCK_STREAM, 0); + if (s < 0) { + perror("cannot create socket"); + return -1; + } + + switch (ovpn->remote.in4.sin_family) { + case AF_INET: + socklen = sizeof(struct sockaddr_in); + break; + case AF_INET6: + socklen = sizeof(struct sockaddr_in6); + break; + default: + return -EOPNOTSUPP; + } + + ret = connect(s, (struct sockaddr *)&ovpn->remote, socklen); + if (ret < 0) { + perror("connect"); + goto err; + } + + fprintf(stderr, "connected\n"); + + ovpn->socket = s; + + return 0; +err: + close(s); + return ret; +} + +static int ovpn_new_peer(struct ovpn_ctx *ovpn, bool is_tcp) +{ + struct nlattr *attr; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_NEW); + if (!ctx) + return -ENOMEM; + + attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_SOCKET, ovpn->socket); + + if (!is_tcp) { + switch (ovpn->remote.in4.sin_family) { + case AF_INET: + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_REMOTE_IPV4, + ovpn->remote.in4.sin_addr.s_addr); + NLA_PUT_U16(ctx->nl_msg, OVPN_A_PEER_REMOTE_PORT, + ovpn->remote.in4.sin_port); + break; + case AF_INET6: + NLA_PUT(ctx->nl_msg, OVPN_A_PEER_REMOTE_IPV6, + sizeof(ovpn->remote.in6.sin6_addr), + &ovpn->remote.in6.sin6_addr); + NLA_PUT_U32(ctx->nl_msg, + OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID, + ovpn->remote.in6.sin6_scope_id); + NLA_PUT_U16(ctx->nl_msg, OVPN_A_PEER_REMOTE_PORT, + ovpn->remote.in6.sin6_port); + break; + default: + fprintf(stderr, + "Invalid family for remote socket address\n"); + goto nla_put_failure; + } + } + + if (ovpn->peer_ip_set) { + switch (ovpn->peer_ip.in4.sin_family) { + case AF_INET: + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_VPN_IPV4, + ovpn->peer_ip.in4.sin_addr.s_addr); + break; + case AF_INET6: + NLA_PUT(ctx->nl_msg, OVPN_A_PEER_VPN_IPV6, + sizeof(struct in6_addr), + &ovpn->peer_ip.in6.sin6_addr); + break; + default: + fprintf(stderr, "Invalid family for peer address\n"); + goto nla_put_failure; + } + } + + nla_nest_end(ctx->nl_msg, attr); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_set_peer(struct ovpn_ctx *ovpn) +{ + struct nlattr *attr; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_SET); + if (!ctx) + return -ENOMEM; + + attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_KEEPALIVE_INTERVAL, + ovpn->keepalive_interval); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_KEEPALIVE_TIMEOUT, + ovpn->keepalive_timeout); + nla_nest_end(ctx->nl_msg, attr); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_del_peer(struct ovpn_ctx *ovpn) +{ + struct nlattr *attr; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_DEL); + if (!ctx) + return -ENOMEM; + + attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id); + nla_nest_end(ctx->nl_msg, attr); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_handle_peer(struct nl_msg *msg, void (*arg)__always_unused) +{ + struct nlattr *pattrs[OVPN_A_PEER_MAX + 1]; + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *attrs[OVPN_A_MAX + 1]; + __u16 rport = 0, lport = 0; + + nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL); + + if (!attrs[OVPN_A_PEER]) { + fprintf(stderr, "no packet content in netlink message\n"); + return NL_SKIP; + } + + nla_parse(pattrs, OVPN_A_PEER_MAX, nla_data(attrs[OVPN_A_PEER]), + nla_len(attrs[OVPN_A_PEER]), NULL); + + if (pattrs[OVPN_A_PEER_ID]) + fprintf(stderr, "* Peer %u\n", + nla_get_u32(pattrs[OVPN_A_PEER_ID])); + + if (pattrs[OVPN_A_PEER_SOCKET_NETNSID]) + fprintf(stderr, "\tsocket NetNS ID: %d\n", + nla_get_s32(pattrs[OVPN_A_PEER_SOCKET_NETNSID])); + + if (pattrs[OVPN_A_PEER_VPN_IPV4]) { + char buf[INET_ADDRSTRLEN]; + + inet_ntop(AF_INET, nla_data(pattrs[OVPN_A_PEER_VPN_IPV4]), + buf, sizeof(buf)); + fprintf(stderr, "\tVPN IPv4: %s\n", buf); + } + + if (pattrs[OVPN_A_PEER_VPN_IPV6]) { + char buf[INET6_ADDRSTRLEN]; + + inet_ntop(AF_INET6, nla_data(pattrs[OVPN_A_PEER_VPN_IPV6]), + buf, sizeof(buf)); + fprintf(stderr, "\tVPN IPv6: %s\n", buf); + } + + if (pattrs[OVPN_A_PEER_LOCAL_PORT]) + lport = ntohs(nla_get_u16(pattrs[OVPN_A_PEER_LOCAL_PORT])); + + if (pattrs[OVPN_A_PEER_REMOTE_PORT]) + rport = ntohs(nla_get_u16(pattrs[OVPN_A_PEER_REMOTE_PORT])); + + if (pattrs[OVPN_A_PEER_REMOTE_IPV6]) { + void *ip = pattrs[OVPN_A_PEER_REMOTE_IPV6]; + char buf[INET6_ADDRSTRLEN]; + int scope_id = -1; + + if (pattrs[OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID]) { + void *p = pattrs[OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID]; + + scope_id = nla_get_u32(p); + } + + inet_ntop(AF_INET6, nla_data(ip), buf, sizeof(buf)); + fprintf(stderr, "\tRemote: %s:%hu (scope-id: %u)\n", buf, rport, + scope_id); + + if (pattrs[OVPN_A_PEER_LOCAL_IPV6]) { + void *ip = pattrs[OVPN_A_PEER_LOCAL_IPV6]; + + inet_ntop(AF_INET6, nla_data(ip), buf, sizeof(buf)); + fprintf(stderr, "\tLocal: %s:%hu\n", buf, lport); + } + } + + if (pattrs[OVPN_A_PEER_REMOTE_IPV4]) { + void *ip = pattrs[OVPN_A_PEER_REMOTE_IPV4]; + char buf[INET_ADDRSTRLEN]; + + inet_ntop(AF_INET, nla_data(ip), buf, sizeof(buf)); + fprintf(stderr, "\tRemote: %s:%hu\n", buf, rport); + + if (pattrs[OVPN_A_PEER_LOCAL_IPV4]) { + void *p = pattrs[OVPN_A_PEER_LOCAL_IPV4]; + + inet_ntop(AF_INET, nla_data(p), buf, sizeof(buf)); + fprintf(stderr, "\tLocal: %s:%hu\n", buf, lport); + } + } + + if (pattrs[OVPN_A_PEER_KEEPALIVE_INTERVAL]) { + void *p = pattrs[OVPN_A_PEER_KEEPALIVE_INTERVAL]; + + fprintf(stderr, "\tKeepalive interval: %u sec\n", + nla_get_u32(p)); + } + + if (pattrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT]) + fprintf(stderr, "\tKeepalive timeout: %u sec\n", + nla_get_u32(pattrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT])); + + if (pattrs[OVPN_A_PEER_VPN_RX_BYTES]) + fprintf(stderr, "\tVPN RX bytes: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_VPN_RX_BYTES])); + + if (pattrs[OVPN_A_PEER_VPN_TX_BYTES]) + fprintf(stderr, "\tVPN TX bytes: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_VPN_TX_BYTES])); + + if (pattrs[OVPN_A_PEER_VPN_RX_PACKETS]) + fprintf(stderr, "\tVPN RX packets: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_VPN_RX_PACKETS])); + + if (pattrs[OVPN_A_PEER_VPN_TX_PACKETS]) + fprintf(stderr, "\tVPN TX packets: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_VPN_TX_PACKETS])); + + if (pattrs[OVPN_A_PEER_LINK_RX_BYTES]) + fprintf(stderr, "\tLINK RX bytes: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_LINK_RX_BYTES])); + + if (pattrs[OVPN_A_PEER_LINK_TX_BYTES]) + fprintf(stderr, "\tLINK TX bytes: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_LINK_TX_BYTES])); + + if (pattrs[OVPN_A_PEER_LINK_RX_PACKETS]) + fprintf(stderr, "\tLINK RX packets: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_LINK_RX_PACKETS])); + + if (pattrs[OVPN_A_PEER_LINK_TX_PACKETS]) + fprintf(stderr, "\tLINK TX packets: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_LINK_TX_PACKETS])); + + return NL_SKIP; +} + +static int ovpn_get_peer(struct ovpn_ctx *ovpn) +{ + int flags = 0, ret = -1; + struct nlattr *attr; + struct nl_ctx *ctx; + + if (ovpn->peer_id == PEER_ID_UNDEF) + flags = NLM_F_DUMP; + + ctx = nl_ctx_alloc_flags(ovpn, OVPN_CMD_PEER_GET, flags); + if (!ctx) + return -ENOMEM; + + if (ovpn->peer_id != PEER_ID_UNDEF) { + attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id); + nla_nest_end(ctx->nl_msg, attr); + } + + ret = ovpn_nl_msg_send(ctx, ovpn_handle_peer); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_new_key(struct ovpn_ctx *ovpn) +{ + struct nlattr *keyconf, *key_dir; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_NEW); + if (!ctx) + return -ENOMEM; + + keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_KEY_ID, ovpn->key_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_CIPHER_ALG, ovpn->cipher); + + key_dir = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF_ENCRYPT_DIR); + NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_CIPHER_KEY, KEY_LEN, ovpn->key_enc); + NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_NONCE_TAIL, NONCE_LEN, ovpn->nonce); + nla_nest_end(ctx->nl_msg, key_dir); + + key_dir = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF_DECRYPT_DIR); + NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_CIPHER_KEY, KEY_LEN, ovpn->key_dec); + NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_NONCE_TAIL, NONCE_LEN, ovpn->nonce); + nla_nest_end(ctx->nl_msg, key_dir); + + nla_nest_end(ctx->nl_msg, keyconf); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_del_key(struct ovpn_ctx *ovpn) +{ + struct nlattr *keyconf; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_DEL); + if (!ctx) + return -ENOMEM; + + keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot); + nla_nest_end(ctx->nl_msg, keyconf); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_handle_key(struct nl_msg *msg, void (*arg)__always_unused) +{ + struct nlattr *kattrs[OVPN_A_KEYCONF_MAX + 1]; + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *attrs[OVPN_A_MAX + 1]; + + nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL); + + if (!attrs[OVPN_A_KEYCONF]) { + fprintf(stderr, "no packet content in netlink message\n"); + return NL_SKIP; + } + + nla_parse(kattrs, OVPN_A_KEYCONF_MAX, nla_data(attrs[OVPN_A_KEYCONF]), + nla_len(attrs[OVPN_A_KEYCONF]), NULL); + + if (kattrs[OVPN_A_KEYCONF_PEER_ID]) + fprintf(stderr, "* Peer %u\n", + nla_get_u32(kattrs[OVPN_A_KEYCONF_PEER_ID])); + if (kattrs[OVPN_A_KEYCONF_SLOT]) { + fprintf(stderr, "\t- Slot: "); + switch (nla_get_u32(kattrs[OVPN_A_KEYCONF_SLOT])) { + case OVPN_KEY_SLOT_PRIMARY: + fprintf(stderr, "primary\n"); + break; + case OVPN_KEY_SLOT_SECONDARY: + fprintf(stderr, "secondary\n"); + break; + default: + fprintf(stderr, "invalid (%u)\n", + nla_get_u32(kattrs[OVPN_A_KEYCONF_SLOT])); + break; + } + } + if (kattrs[OVPN_A_KEYCONF_KEY_ID]) + fprintf(stderr, "\t- Key ID: %u\n", + nla_get_u32(kattrs[OVPN_A_KEYCONF_KEY_ID])); + if (kattrs[OVPN_A_KEYCONF_CIPHER_ALG]) { + fprintf(stderr, "\t- Cipher: "); + switch (nla_get_u32(kattrs[OVPN_A_KEYCONF_CIPHER_ALG])) { + case OVPN_CIPHER_ALG_NONE: + fprintf(stderr, "none\n"); + break; + case OVPN_CIPHER_ALG_AES_GCM: + fprintf(stderr, "aes-gcm\n"); + break; + case OVPN_CIPHER_ALG_CHACHA20_POLY1305: + fprintf(stderr, "chacha20poly1305\n"); + break; + default: + fprintf(stderr, "invalid (%u)\n", + nla_get_u32(kattrs[OVPN_A_KEYCONF_CIPHER_ALG])); + break; + } + } + + return NL_SKIP; +} + +static int ovpn_get_key(struct ovpn_ctx *ovpn) +{ + struct nlattr *keyconf; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_GET); + if (!ctx) + return -ENOMEM; + + keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot); + nla_nest_end(ctx->nl_msg, keyconf); + + ret = ovpn_nl_msg_send(ctx, ovpn_handle_key); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_swap_keys(struct ovpn_ctx *ovpn) +{ + struct nl_ctx *ctx; + struct nlattr *kc; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_SWAP); + if (!ctx) + return -ENOMEM; + + kc = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id); + nla_nest_end(ctx->nl_msg, kc); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +/* Helper function used to easily add attributes to a rtnl message */ +static int ovpn_addattr(struct nlmsghdr *n, int maxlen, int type, + const void *data, int alen) +{ + int len = RTA_LENGTH(alen); + struct rtattr *rta; + + if ((int)(NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len)) > maxlen) { + fprintf(stderr, "%s: rtnl: message exceeded bound of %d\n", + __func__, maxlen); + return -EMSGSIZE; + } + + rta = nlmsg_tail(n); + rta->rta_type = type; + rta->rta_len = len; + + if (!data) + memset(RTA_DATA(rta), 0, alen); + else + memcpy(RTA_DATA(rta), data, alen); + + n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len); + + return 0; +} + +static struct rtattr *ovpn_nest_start(struct nlmsghdr *msg, size_t max_size, + int attr) +{ + struct rtattr *nest = nlmsg_tail(msg); + + if (ovpn_addattr(msg, max_size, attr, NULL, 0) < 0) + return NULL; + + return nest; +} + +static void ovpn_nest_end(struct nlmsghdr *msg, struct rtattr *nest) +{ + nest->rta_len = (uint8_t *)nlmsg_tail(msg) - (uint8_t *)nest; +} + +#define RT_SNDBUF_SIZE (1024 * 2) +#define RT_RCVBUF_SIZE (1024 * 4) + +/* Open RTNL socket */ +static int ovpn_rt_socket(void) +{ + int sndbuf = RT_SNDBUF_SIZE, rcvbuf = RT_RCVBUF_SIZE, fd; + + fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (fd < 0) { + fprintf(stderr, "%s: cannot open netlink socket\n", __func__); + return fd; + } + + if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &sndbuf, + sizeof(sndbuf)) < 0) { + fprintf(stderr, "%s: SO_SNDBUF\n", __func__); + close(fd); + return -1; + } + + if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, + sizeof(rcvbuf)) < 0) { + fprintf(stderr, "%s: SO_RCVBUF\n", __func__); + close(fd); + return -1; + } + + return fd; +} + +/* Bind socket to Netlink subsystem */ +static int ovpn_rt_bind(int fd, uint32_t groups) +{ + struct sockaddr_nl local = { 0 }; + socklen_t addr_len; + + local.nl_family = AF_NETLINK; + local.nl_groups = groups; + + if (bind(fd, (struct sockaddr *)&local, sizeof(local)) < 0) { + fprintf(stderr, "%s: cannot bind netlink socket: %d\n", + __func__, errno); + return -errno; + } + + addr_len = sizeof(local); + if (getsockname(fd, (struct sockaddr *)&local, &addr_len) < 0) { + fprintf(stderr, "%s: cannot getsockname: %d\n", __func__, + errno); + return -errno; + } + + if (addr_len != sizeof(local)) { + fprintf(stderr, "%s: wrong address length %d\n", __func__, + addr_len); + return -EINVAL; + } + + if (local.nl_family != AF_NETLINK) { + fprintf(stderr, "%s: wrong address family %d\n", __func__, + local.nl_family); + return -EINVAL; + } + + return 0; +} + +typedef int (*ovpn_parse_reply_cb)(struct nlmsghdr *msg, void *arg); + +/* Send Netlink message and run callback on reply (if specified) */ +static int ovpn_rt_send(struct nlmsghdr *payload, pid_t peer, + unsigned int groups, ovpn_parse_reply_cb cb, + void *arg_cb) +{ + int len, rem_len, fd, ret, rcv_len; + struct sockaddr_nl nladdr = { 0 }; + struct nlmsgerr *err; + struct nlmsghdr *h; + char buf[1024 * 16]; + struct iovec iov = { + .iov_base = payload, + .iov_len = payload->nlmsg_len, + }; + struct msghdr nlmsg = { + .msg_name = &nladdr, + .msg_namelen = sizeof(nladdr), + .msg_iov = &iov, + .msg_iovlen = 1, + }; + + nladdr.nl_family = AF_NETLINK; + nladdr.nl_pid = peer; + nladdr.nl_groups = groups; + + payload->nlmsg_seq = time(NULL); + + /* no need to send reply */ + if (!cb) + payload->nlmsg_flags |= NLM_F_ACK; + + fd = ovpn_rt_socket(); + if (fd < 0) { + fprintf(stderr, "%s: can't open rtnl socket\n", __func__); + return -errno; + } + + ret = ovpn_rt_bind(fd, 0); + if (ret < 0) { + fprintf(stderr, "%s: can't bind rtnl socket\n", __func__); + ret = -errno; + goto out; + } + + ret = sendmsg(fd, &nlmsg, 0); + if (ret < 0) { + fprintf(stderr, "%s: rtnl: error on sendmsg()\n", __func__); + ret = -errno; + goto out; + } + + /* prepare buffer to store RTNL replies */ + memset(buf, 0, sizeof(buf)); + iov.iov_base = buf; + + while (1) { + /* + * iov_len is modified by recvmsg(), therefore has to be initialized before + * using it again + */ + iov.iov_len = sizeof(buf); + rcv_len = recvmsg(fd, &nlmsg, 0); + if (rcv_len < 0) { + if (errno == EINTR || errno == EAGAIN) { + fprintf(stderr, "%s: interrupted call\n", + __func__); + continue; + } + fprintf(stderr, "%s: rtnl: error on recvmsg()\n", + __func__); + ret = -errno; + goto out; + } + + if (rcv_len == 0) { + fprintf(stderr, + "%s: rtnl: socket reached unexpected EOF\n", + __func__); + ret = -EIO; + goto out; + } + + if (nlmsg.msg_namelen != sizeof(nladdr)) { + fprintf(stderr, + "%s: sender address length: %u (expected %zu)\n", + __func__, nlmsg.msg_namelen, sizeof(nladdr)); + ret = -EIO; + goto out; + } + + h = (struct nlmsghdr *)buf; + while (rcv_len >= (int)sizeof(*h)) { + len = h->nlmsg_len; + rem_len = len - sizeof(*h); + + if (rem_len < 0 || len > rcv_len) { + if (nlmsg.msg_flags & MSG_TRUNC) { + fprintf(stderr, "%s: truncated message\n", + __func__); + ret = -EIO; + goto out; + } + fprintf(stderr, "%s: malformed message: len=%d\n", + __func__, len); + ret = -EIO; + goto out; + } + + if (h->nlmsg_type == NLMSG_DONE) { + ret = 0; + goto out; + } + + if (h->nlmsg_type == NLMSG_ERROR) { + err = (struct nlmsgerr *)NLMSG_DATA(h); + if (rem_len < (int)sizeof(struct nlmsgerr)) { + fprintf(stderr, "%s: ERROR truncated\n", + __func__); + ret = -EIO; + goto out; + } + + if (err->error) { + fprintf(stderr, "%s: (%d) %s\n", + __func__, err->error, + strerror(-err->error)); + ret = err->error; + goto out; + } + + ret = 0; + if (cb) { + int r = cb(h, arg_cb); + + if (r <= 0) + ret = r; + } + goto out; + } + + if (cb) { + int r = cb(h, arg_cb); + + if (r <= 0) { + ret = r; + goto out; + } + } else { + fprintf(stderr, "%s: RTNL: unexpected reply\n", + __func__); + } + + rcv_len -= NLMSG_ALIGN(len); + h = (struct nlmsghdr *)((uint8_t *)h + + NLMSG_ALIGN(len)); + } + + if (nlmsg.msg_flags & MSG_TRUNC) { + fprintf(stderr, "%s: message truncated\n", __func__); + continue; + } + + if (rcv_len) { + fprintf(stderr, "%s: rtnl: %d not parsed bytes\n", + __func__, rcv_len); + ret = -1; + goto out; + } + } +out: + close(fd); + + return ret; +} + +struct ovpn_link_req { + struct nlmsghdr n; + struct ifinfomsg i; + char buf[256]; +}; + +static int ovpn_new_iface(struct ovpn_ctx *ovpn) +{ + struct rtattr *linkinfo, *data; + struct ovpn_link_req req = { 0 }; + int ret = -1; + + fprintf(stdout, "Creating interface %s with mode %u\n", ovpn->ifname, + ovpn->mode); + + req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i)); + req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL; + req.n.nlmsg_type = RTM_NEWLINK; + + if (ovpn_addattr(&req.n, sizeof(req), IFLA_IFNAME, ovpn->ifname, + strlen(ovpn->ifname) + 1) < 0) + goto err; + + linkinfo = ovpn_nest_start(&req.n, sizeof(req), IFLA_LINKINFO); + if (!linkinfo) + goto err; + + if (ovpn_addattr(&req.n, sizeof(req), IFLA_INFO_KIND, OVPN_FAMILY_NAME, + strlen(OVPN_FAMILY_NAME) + 1) < 0) + goto err; + + if (ovpn->mode_set) { + data = ovpn_nest_start(&req.n, sizeof(req), IFLA_INFO_DATA); + if (!data) + goto err; + + if (ovpn_addattr(&req.n, sizeof(req), IFLA_OVPN_MODE, + &ovpn->mode, sizeof(uint8_t)) < 0) + goto err; + + ovpn_nest_end(&req.n, data); + } + + ovpn_nest_end(&req.n, linkinfo); + + req.i.ifi_family = AF_PACKET; + + ret = ovpn_rt_send(&req.n, 0, 0, NULL, NULL); +err: + return ret; +} + +static int ovpn_del_iface(struct ovpn_ctx *ovpn) +{ + struct ovpn_link_req req = { 0 }; + + fprintf(stdout, "Deleting interface %s ifindex %u\n", ovpn->ifname, + ovpn->ifindex); + + req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i)); + req.n.nlmsg_flags = NLM_F_REQUEST; + req.n.nlmsg_type = RTM_DELLINK; + + req.i.ifi_family = AF_PACKET; + req.i.ifi_index = ovpn->ifindex; + + return ovpn_rt_send(&req.n, 0, 0, NULL, NULL); +} + +static int nl_seq_check(struct nl_msg (*msg)__always_unused, + void (*arg)__always_unused) +{ + return NL_OK; +} + +struct mcast_handler_args { + const char *group; + int id; +}; + +static int mcast_family_handler(struct nl_msg *msg, void *arg) +{ + struct mcast_handler_args *grp = arg; + struct nlattr *tb[CTRL_ATTR_MAX + 1]; + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *mcgrp; + int rem_mcgrp; + + nla_parse(tb, CTRL_ATTR_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL); + + if (!tb[CTRL_ATTR_MCAST_GROUPS]) + return NL_SKIP; + + nla_for_each_nested(mcgrp, tb[CTRL_ATTR_MCAST_GROUPS], rem_mcgrp) { + struct nlattr *tb_mcgrp[CTRL_ATTR_MCAST_GRP_MAX + 1]; + + nla_parse(tb_mcgrp, CTRL_ATTR_MCAST_GRP_MAX, + nla_data(mcgrp), nla_len(mcgrp), NULL); + + if (!tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME] || + !tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]) + continue; + if (strncmp(nla_data(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]), + grp->group, nla_len(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]))) + continue; + grp->id = nla_get_u32(tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]); + break; + } + + return NL_SKIP; +} + +static int mcast_error_handler(struct sockaddr_nl (*nla)__always_unused, + struct nlmsgerr *err, void *arg) +{ + int *ret = arg; + + *ret = err->error; + return NL_STOP; +} + +static int mcast_ack_handler(struct nl_msg (*msg)__always_unused, void *arg) +{ + int *ret = arg; + + *ret = 0; + return NL_STOP; +} + +static int ovpn_handle_msg(struct nl_msg *msg, void *arg) +{ + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *attrs[OVPN_A_MAX + 1]; + struct nlmsghdr *nlh = nlmsg_hdr(msg); + //enum ovpn_del_peer_reason reason; + char ifname[IF_NAMESIZE]; + int *ret = arg; + __u32 ifindex; + + fprintf(stderr, "received message from ovpn-dco\n"); + + *ret = -1; + + if (!genlmsg_valid_hdr(nlh, 0)) { + fprintf(stderr, "invalid header\n"); + return NL_STOP; + } + + if (nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL)) { + fprintf(stderr, "received bogus data from ovpn-dco\n"); + return NL_STOP; + } + + if (!attrs[OVPN_A_IFINDEX]) { + fprintf(stderr, "no ifindex in this message\n"); + return NL_STOP; + } + + ifindex = nla_get_u32(attrs[OVPN_A_IFINDEX]); + if (!if_indextoname(ifindex, ifname)) { + fprintf(stderr, "cannot resolve ifname for ifindex: %u\n", + ifindex); + return NL_STOP; + } + + switch (gnlh->cmd) { + case OVPN_CMD_PEER_DEL_NTF: + /*if (!attrs[OVPN_A_DEL_PEER_REASON]) { + * fprintf(stderr, "no reason in DEL_PEER message\n"); + * return NL_STOP; + *} + * + *reason = nla_get_u8(attrs[OVPN_A_DEL_PEER_REASON]); + *fprintf(stderr, + * "received CMD_DEL_PEER, ifname: %s reason: %d\n", + * ifname, reason); + */ + fprintf(stdout, "received CMD_PEER_DEL_NTF\n"); + break; + case OVPN_CMD_KEY_SWAP_NTF: + fprintf(stdout, "received CMD_KEY_SWAP_NTF\n"); + break; + default: + fprintf(stderr, "received unknown command: %d\n", gnlh->cmd); + return NL_STOP; + } + + *ret = 0; + return NL_OK; +} + +static int ovpn_get_mcast_id(struct nl_sock *sock, const char *family, + const char *group) +{ + struct nl_msg *msg; + struct nl_cb *cb; + int ret, ctrlid; + struct mcast_handler_args grp = { + .group = group, + .id = -ENOENT, + }; + + msg = nlmsg_alloc(); + if (!msg) + return -ENOMEM; + + cb = nl_cb_alloc(NL_CB_DEFAULT); + if (!cb) { + ret = -ENOMEM; + goto out_fail_cb; + } + + ctrlid = genl_ctrl_resolve(sock, "nlctrl"); + + genlmsg_put(msg, 0, 0, ctrlid, 0, 0, CTRL_CMD_GETFAMILY, 0); + + ret = -ENOBUFS; + NLA_PUT_STRING(msg, CTRL_ATTR_FAMILY_NAME, family); + + ret = nl_send_auto_complete(sock, msg); + if (ret < 0) + goto nla_put_failure; + + ret = 1; + + nl_cb_err(cb, NL_CB_CUSTOM, mcast_error_handler, &ret); + nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, mcast_ack_handler, &ret); + nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, mcast_family_handler, &grp); + + while (ret > 0) + nl_recvmsgs(sock, cb); + + if (ret == 0) + ret = grp.id; + nla_put_failure: + nl_cb_put(cb); + out_fail_cb: + nlmsg_free(msg); + return ret; +} + +static int ovpn_listen_mcast(void) +{ + struct nl_sock *sock; + struct nl_cb *cb; + int mcid, ret; + + sock = nl_socket_alloc(); + if (!sock) { + fprintf(stderr, "cannot allocate netlink socket\n"); + goto err_free; + } + + nl_socket_set_buffer_size(sock, 8192, 8192); + + ret = genl_connect(sock); + if (ret < 0) { + fprintf(stderr, "cannot connect to generic netlink: %s\n", + nl_geterror(ret)); + goto err_free; + } + + mcid = ovpn_get_mcast_id(sock, OVPN_FAMILY_NAME, OVPN_MCGRP_PEERS); + if (mcid < 0) { + fprintf(stderr, "cannot get mcast group: %s\n", + nl_geterror(mcid)); + goto err_free; + } + + ret = nl_socket_add_membership(sock, mcid); + if (ret) { + fprintf(stderr, "failed to join mcast group: %d\n", ret); + goto err_free; + } + + ret = 1; + cb = nl_cb_alloc(NL_CB_DEFAULT); + nl_cb_set(cb, NL_CB_SEQ_CHECK, NL_CB_CUSTOM, nl_seq_check, NULL); + nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, ovpn_handle_msg, &ret); + nl_cb_err(cb, NL_CB_CUSTOM, ovpn_nl_cb_error, &ret); + + while (ret == 1) { + int err = nl_recvmsgs(sock, cb); + + if (err < 0) { + fprintf(stderr, + "cannot receive netlink message: (%d) %s\n", + err, nl_geterror(-err)); + ret = -1; + break; + } + } + + nl_cb_put(cb); +err_free: + nl_socket_free(sock); + return ret; +} + +static void usage(const char *cmd) +{ + fprintf(stderr, + "Usage %s <command> <iface> [arguments..]\n", + cmd); + fprintf(stderr, "where <command> can be one of the following\n\n"); + + fprintf(stderr, "* new_iface <iface> [mode]: create new ovpn interface\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tmode:\n"); + fprintf(stderr, "\t\t- P2P for peer-to-peer mode (i.e. client)\n"); + fprintf(stderr, "\t\t- MP for multi-peer mode (i.e. server)\n"); + + fprintf(stderr, "* del_iface <iface>: delete ovpn interface\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + + fprintf(stderr, + "* listen <iface> <lport> <peers_file> [ipv6]: listen for incoming peer TCP connections\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tlport: TCP port to listen to\n"); + fprintf(stderr, + "\tpeers_file: file containing one peer per line: Line format:\n"); + fprintf(stderr, "\t\t<peer_id> <vpnaddr>\n"); + fprintf(stderr, + "\tipv6: whether the socket should listen to the IPv6 wildcard address\n"); + + fprintf(stderr, + "* connect <iface> <peer_id> <raddr> <rport> [key_file]: start connecting peer of TCP-based VPN session\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the connecting peer\n"); + fprintf(stderr, "\traddr: peer IP address to connect to\n"); + fprintf(stderr, "\trport: peer TCP port to connect to\n"); + fprintf(stderr, + "\tkey_file: file containing the symmetric key for encryption\n"); + + fprintf(stderr, + "* new_peer <iface> <peer_id> <lport> <raddr> <rport> [vpnaddr]: add new peer\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tlport: local UDP port to bind to\n"); + fprintf(stderr, + "\tpeer_id: peer ID to be used in data packets to/from this peer\n"); + fprintf(stderr, "\traddr: peer IP address\n"); + fprintf(stderr, "\trport: peer UDP port\n"); + fprintf(stderr, "\tvpnaddr: peer VPN IP\n"); + + fprintf(stderr, + "* new_multi_peer <iface> <lport> <peers_file>: add multiple peers as listed in the file\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tlport: local UDP port to bind to\n"); + fprintf(stderr, + "\tpeers_file: text file containing one peer per line. Line format:\n"); + fprintf(stderr, "\t\t<peer_id> <raddr> <rport> <vpnaddr>\n"); + + fprintf(stderr, + "* set_peer <iface> <peer_id> <keepalive_interval> <keepalive_timeout>: set peer attributes\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n"); + fprintf(stderr, + "\tkeepalive_interval: interval for sending ping messages\n"); + fprintf(stderr, + "\tkeepalive_timeout: time after which a peer is timed out\n"); + + fprintf(stderr, "* del_peer <iface> <peer_id>: delete peer\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to delete\n"); + + fprintf(stderr, "* get_peer <iface> [peer_id]: retrieve peer(s) status\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, + "\tpeer_id: peer ID of the peer to query. All peers are returned if omitted\n"); + + fprintf(stderr, + "* new_key <iface> <peer_id> <slot> <key_id> <cipher> <key_dir> <key_file>: set data channel key\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, + "\tpeer_id: peer ID of the peer to configure the key for\n"); + fprintf(stderr, "\tslot: either 1 (primary) or 2 (secondary)\n"); + fprintf(stderr, "\tkey_id: an ID from 0 to 7\n"); + fprintf(stderr, + "\tcipher: cipher to use, supported: aes (AES-GCM), chachapoly (CHACHA20POLY1305)\n"); + fprintf(stderr, + "\tkey_dir: key direction, must 0 on one host and 1 on the other\n"); + fprintf(stderr, "\tkey_file: file containing the pre-shared key\n"); + + fprintf(stderr, + "* del_key <iface> <peer_id> [slot]: erase existing data channel key\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n"); + fprintf(stderr, "\tslot: slot to erase. PRIMARY if omitted\n"); + + fprintf(stderr, + "* get_key <iface> <peer_id> <slot>: retrieve non sensible key data\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to query\n"); + fprintf(stderr, "\tslot: either 1 (primary) or 2 (secondary)\n"); + + fprintf(stderr, + "* swap_keys <iface> <peer_id>: swap content of primary and secondary key slots\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n"); + + fprintf(stderr, + "* listen_mcast: listen to ovpn netlink multicast messages\n"); +} + +static int ovpn_parse_remote(struct ovpn_ctx *ovpn, const char *host, + const char *service, const char *vpnip) +{ + int ret; + struct addrinfo *result; + struct addrinfo hints = { + .ai_family = ovpn->sa_family, + .ai_socktype = SOCK_DGRAM, + .ai_protocol = IPPROTO_UDP + }; + + if (host) { + ret = getaddrinfo(host, service, &hints, &result); + if (ret == EAI_NONAME || ret == EAI_FAIL) + return -1; + + if (!(result->ai_family == AF_INET && + result->ai_addrlen == sizeof(struct sockaddr_in)) && + !(result->ai_family == AF_INET6 && + result->ai_addrlen == sizeof(struct sockaddr_in6))) { + ret = -EINVAL; + goto out; + } + + memcpy(&ovpn->remote, result->ai_addr, result->ai_addrlen); + } + + if (vpnip) { + ret = getaddrinfo(vpnip, NULL, &hints, &result); + if (ret == EAI_NONAME || ret == EAI_FAIL) + return -1; + + if (!(result->ai_family == AF_INET && + result->ai_addrlen == sizeof(struct sockaddr_in)) && + !(result->ai_family == AF_INET6 && + result->ai_addrlen == sizeof(struct sockaddr_in6))) { + ret = -EINVAL; + goto out; + } + + memcpy(&ovpn->peer_ip, result->ai_addr, result->ai_addrlen); + ovpn->sa_family = result->ai_family; + + ovpn->peer_ip_set = true; + } + + ret = 0; +out: + freeaddrinfo(result); + return ret; +} + +static int ovpn_parse_new_peer(struct ovpn_ctx *ovpn, const char *peer_id, + const char *raddr, const char *rport, + const char *vpnip) +{ + ovpn->peer_id = strtoul(peer_id, NULL, 10); + if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + return ovpn_parse_remote(ovpn, raddr, rport, vpnip); +} + +static int ovpn_parse_key_slot(const char *arg, struct ovpn_ctx *ovpn) +{ + int slot = strtoul(arg, NULL, 10); + + if (errno == ERANGE || slot < 1 || slot > 2) { + fprintf(stderr, "key slot out of range\n"); + return -1; + } + + switch (slot) { + case 1: + ovpn->key_slot = OVPN_KEY_SLOT_PRIMARY; + break; + case 2: + ovpn->key_slot = OVPN_KEY_SLOT_SECONDARY; + break; + } + + return 0; +} + +static int ovpn_send_tcp_data(int socket) +{ + uint16_t len = htons(1000); + uint8_t buf[1002]; + int ret; + + memcpy(buf, &len, sizeof(len)); + memset(buf + sizeof(len), 0x86, sizeof(buf) - sizeof(len)); + + ret = send(socket, buf, sizeof(buf), 0); + + fprintf(stdout, "Sent %u bytes over TCP socket\n", ret); + + return ret > 0 ? 0 : ret; +} + +static int ovpn_recv_tcp_data(int socket) +{ + uint8_t buf[1002]; + uint16_t len; + int ret; + + ret = recv(socket, buf, sizeof(buf), 0); + + if (ret < 2) { + fprintf(stderr, ">>>> Error while reading TCP data: %d\n", ret); + return ret; + } + + memcpy(&len, buf, sizeof(len)); + len = ntohs(len); + + fprintf(stdout, ">>>> Received %u bytes over TCP socket, header: %u\n", + ret, len); + +/* int i; + * for (i = 2; i < ret; i++) { + * fprintf(stdout, "0x%.2x ", buf[i]); + * if (i && !((i - 2) % 16)) + * fprintf(stdout, "\n"); + * } + * fprintf(stdout, "\n"); + */ + return 0; +} + +static enum ovpn_cmd ovpn_parse_cmd(const char *cmd) +{ + if (!strcmp(cmd, "new_iface")) + return CMD_NEW_IFACE; + + if (!strcmp(cmd, "del_iface")) + return CMD_DEL_IFACE; + + if (!strcmp(cmd, "listen")) + return CMD_LISTEN; + + if (!strcmp(cmd, "connect")) + return CMD_CONNECT; + + if (!strcmp(cmd, "new_peer")) + return CMD_NEW_PEER; + + if (!strcmp(cmd, "new_multi_peer")) + return CMD_NEW_MULTI_PEER; + + if (!strcmp(cmd, "set_peer")) + return CMD_SET_PEER; + + if (!strcmp(cmd, "del_peer")) + return CMD_DEL_PEER; + + if (!strcmp(cmd, "get_peer")) + return CMD_GET_PEER; + + if (!strcmp(cmd, "new_key")) + return CMD_NEW_KEY; + + if (!strcmp(cmd, "del_key")) + return CMD_DEL_KEY; + + if (!strcmp(cmd, "get_key")) + return CMD_GET_KEY; + + if (!strcmp(cmd, "swap_keys")) + return CMD_SWAP_KEYS; + + if (!strcmp(cmd, "listen_mcast")) + return CMD_LISTEN_MCAST; + + return CMD_INVALID; +} + +static int ovpn_run_cmd(struct ovpn_ctx *ovpn) +{ + char peer_id[10], vpnip[INET6_ADDRSTRLEN], raddr[128], rport[10]; + int n, ret; + FILE *fp; + + switch (ovpn->cmd) { + case CMD_NEW_IFACE: + ret = ovpn_new_iface(ovpn); + break; + case CMD_DEL_IFACE: + ret = ovpn_del_iface(ovpn); + break; + case CMD_LISTEN: + ret = ovpn_listen(ovpn, ovpn->sa_family); + if (ret < 0) { + fprintf(stderr, "cannot listen on TCP socket\n"); + return ret; + } + + fp = fopen(ovpn->peers_file, "r"); + if (!fp) { + fprintf(stderr, "cannot open file: %s\n", + ovpn->peers_file); + return -1; + } + + while ((n = fscanf(fp, "%s %s\n", peer_id, vpnip)) == 2) { + struct ovpn_ctx peer_ctx = { 0 }; + + peer_ctx.ifindex = ovpn->ifindex; + peer_ctx.sa_family = ovpn->sa_family; + + peer_ctx.socket = ovpn_accept(ovpn); + if (peer_ctx.socket < 0) { + fprintf(stderr, "cannot accept connection!\n"); + return -1; + } + + /* store the socket of the first peer to test TCP I/O */ + if (ovpn->cli_socket < 0) + ovpn->cli_socket = peer_ctx.socket; + + ret = ovpn_parse_new_peer(&peer_ctx, peer_id, NULL, + NULL, vpnip); + if (ret < 0) { + fprintf(stderr, "error while parsing line\n"); + return -1; + } + + ret = ovpn_new_peer(&peer_ctx, true); + if (ret < 0) { + fprintf(stderr, + "cannot add peer to VPN: %s %s\n", + peer_id, vpnip); + return ret; + } + } + + if (ovpn->cli_socket >= 0) + ret = ovpn_recv_tcp_data(ovpn->cli_socket); + + break; + case CMD_CONNECT: + ret = ovpn_connect(ovpn); + if (ret < 0) { + fprintf(stderr, "cannot connect TCP socket\n"); + return ret; + } + + ret = ovpn_new_peer(ovpn, true); + if (ret < 0) { + fprintf(stderr, "cannot add peer to VPN\n"); + close(ovpn->socket); + return ret; + } + + if (ovpn->cipher != OVPN_CIPHER_ALG_NONE) { + ret = ovpn_new_key(ovpn); + if (ret < 0) { + fprintf(stderr, "cannot set key\n"); + return ret; + } + } + + ret = ovpn_send_tcp_data(ovpn->socket); + break; + case CMD_NEW_PEER: + ret = ovpn_udp_socket(ovpn, AF_INET6); //ovpn->sa_family ? + if (ret < 0) + return ret; + + ret = ovpn_new_peer(ovpn, false); + break; + case CMD_NEW_MULTI_PEER: + ret = ovpn_udp_socket(ovpn, AF_INET6); + if (ret < 0) + return ret; + + fp = fopen(ovpn->peers_file, "r"); + if (!fp) { + fprintf(stderr, "cannot open file: %s\n", + ovpn->peers_file); + return -1; + } + + while ((n = fscanf(fp, "%s %s %s %s\n", peer_id, raddr, rport, + vpnip)) == 4) { + struct ovpn_ctx peer_ctx = { 0 }; + + peer_ctx.ifindex = ovpn->ifindex; + peer_ctx.socket = ovpn->socket; + peer_ctx.sa_family = AF_UNSPEC; + + ret = ovpn_parse_new_peer(&peer_ctx, peer_id, raddr, + rport, vpnip); + if (ret < 0) { + fprintf(stderr, "error while parsing line\n"); + return -1; + } + + ret = ovpn_new_peer(&peer_ctx, false); + if (ret < 0) { + fprintf(stderr, + "cannot add peer to VPN: %s %s %s %s\n", + peer_id, raddr, rport, vpnip); + return ret; + } + } + break; + case CMD_SET_PEER: + ret = ovpn_set_peer(ovpn); + break; + case CMD_DEL_PEER: + ret = ovpn_del_peer(ovpn); + break; + case CMD_GET_PEER: + if (ovpn->peer_id == PEER_ID_UNDEF) + fprintf(stderr, "List of peers connected to: %s\n", + ovpn->ifname); + + ret = ovpn_get_peer(ovpn); + break; + case CMD_NEW_KEY: + ret = ovpn_new_key(ovpn); + break; + case CMD_DEL_KEY: + ret = ovpn_del_key(ovpn); + break; + case CMD_GET_KEY: + ret = ovpn_get_key(ovpn); + break; + case CMD_SWAP_KEYS: + ret = ovpn_swap_keys(ovpn); + break; + case CMD_LISTEN_MCAST: + ret = ovpn_listen_mcast(); + break; + case CMD_INVALID: + break; + } + + return ret; +} + +static int ovpn_parse_cmd_args(struct ovpn_ctx *ovpn, int argc, char *argv[]) +{ + int ret; + + /* no args required for LISTEN_MCAST */ + if (ovpn->cmd == CMD_LISTEN_MCAST) + return 0; + + /* all commands need an ifname */ + if (argc < 3) + return -EINVAL; + + strscpy(ovpn->ifname, argv[2], IFNAMSIZ - 1); + ovpn->ifname[IFNAMSIZ - 1] = '\0'; + + /* all commands, except NEW_IFNAME, needs an ifindex */ + if (ovpn->cmd != CMD_NEW_IFACE) { + ovpn->ifindex = if_nametoindex(ovpn->ifname); + if (!ovpn->ifindex) { + fprintf(stderr, "cannot find interface: %s\n", + strerror(errno)); + return -1; + } + } + + switch (ovpn->cmd) { + case CMD_NEW_IFACE: + if (argc < 4) + break; + + if (!strcmp(argv[3], "P2P")) { + ovpn->mode = OVPN_MODE_P2P; + } else if (!strcmp(argv[3], "MP")) { + ovpn->mode = OVPN_MODE_MP; + } else { + fprintf(stderr, "Cannot parse iface mode: %s\n", + argv[3]); + return -1; + } + ovpn->mode_set = true; + break; + case CMD_DEL_IFACE: + break; + case CMD_LISTEN: + if (argc < 5) + return -EINVAL; + + ovpn->lport = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->lport > 65535) { + fprintf(stderr, "lport value out of range\n"); + return -1; + } + + ovpn->peers_file = argv[4]; + + if (argc > 5 && !strcmp(argv[5], "ipv6")) + ovpn->sa_family = AF_INET6; + break; + case CMD_CONNECT: + if (argc < 6) + return -EINVAL; + + ovpn->sa_family = AF_INET; + + ret = ovpn_parse_new_peer(ovpn, argv[3], argv[4], argv[5], + NULL); + if (ret < 0) { + fprintf(stderr, "Cannot parse remote peer data\n"); + return -1; + } + + if (argc > 6) { + ovpn->key_slot = OVPN_KEY_SLOT_PRIMARY; + ovpn->key_id = 0; + ovpn->cipher = OVPN_CIPHER_ALG_AES_GCM; + ovpn->key_dir = KEY_DIR_OUT; + + ret = ovpn_parse_key(argv[6], ovpn); + if (ret) + return -1; + } + break; + case CMD_NEW_PEER: + if (argc < 7) + return -EINVAL; + + ovpn->lport = strtoul(argv[4], NULL, 10); + if (errno == ERANGE || ovpn->lport > 65535) { + fprintf(stderr, "lport value out of range\n"); + return -1; + } + + const char *vpnip = (argc > 7) ? argv[7] : NULL; + + ret = ovpn_parse_new_peer(ovpn, argv[3], argv[5], argv[6], + vpnip); + if (ret < 0) + return -1; + break; + case CMD_NEW_MULTI_PEER: + if (argc < 5) + return -EINVAL; + + ovpn->lport = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->lport > 65535) { + fprintf(stderr, "lport value out of range\n"); + return -1; + } + + ovpn->peers_file = argv[4]; + break; + case CMD_SET_PEER: + if (argc < 6) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ovpn->keepalive_interval = strtoul(argv[4], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, + "keepalive interval value out of range\n"); + return -1; + } + + ovpn->keepalive_timeout = strtoul(argv[5], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, + "keepalive interval value out of range\n"); + return -1; + } + break; + case CMD_DEL_PEER: + if (argc < 4) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + break; + case CMD_GET_PEER: + ovpn->peer_id = PEER_ID_UNDEF; + if (argc > 3) { + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + } + break; + case CMD_NEW_KEY: + if (argc < 9) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ret = ovpn_parse_key_slot(argv[4], ovpn); + if (ret) + return -1; + + ovpn->key_id = strtoul(argv[5], NULL, 10); + if (errno == ERANGE || ovpn->key_id > 2) { + fprintf(stderr, "key ID out of range\n"); + return -1; + } + + ret = ovpn_parse_cipher(argv[6], ovpn); + if (ret < 0) + return -1; + + ret = ovpn_parse_key_direction(argv[7], ovpn); + if (ret < 0) + return -1; + + ret = ovpn_parse_key(argv[8], ovpn); + if (ret) + return -1; + break; + case CMD_DEL_KEY: + if (argc < 4) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ret = ovpn_parse_key_slot(argv[4], ovpn); + if (ret) + return ret; + break; + case CMD_GET_KEY: + if (argc < 5) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ret = ovpn_parse_key_slot(argv[4], ovpn); + if (ret) + return ret; + break; + case CMD_SWAP_KEYS: + if (argc < 4) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + break; + case CMD_LISTEN_MCAST: + break; + case CMD_INVALID: + break; + } + + return 0; +} + +int main(int argc, char *argv[]) +{ + struct ovpn_ctx ovpn; + int ret; + + if (argc < 2) { + usage(argv[0]); + return -1; + } + + memset(&ovpn, 0, sizeof(ovpn)); + ovpn.sa_family = AF_INET; + ovpn.cipher = OVPN_CIPHER_ALG_NONE; + ovpn.cli_socket = -1; + + ovpn.cmd = ovpn_parse_cmd(argv[1]); + if (ovpn.cmd == CMD_INVALID) { + fprintf(stderr, "Error: unknown command.\n\n"); + usage(argv[0]); + return -1; + } + + ret = ovpn_parse_cmd_args(&ovpn, argc, argv); + if (ret < 0) { + fprintf(stderr, "Error: invalid arguments.\n\n"); + if (ret == -EINVAL) + usage(argv[0]); + return ret; + } + + ret = ovpn_run_cmd(&ovpn); + if (ret) + fprintf(stderr, "Cannot execute command: %s (%d)\n", + strerror(-ret), ret); + + return ret; +} diff --git a/tools/testing/selftests/net/ovpn/tcp_peers.txt b/tools/testing/selftests/net/ovpn/tcp_peers.txt new file mode 100644 index 0000000000000000000000000000000000000000..d753eebe8716ed3588334ad766981e883ed2469a --- /dev/null +++ b/tools/testing/selftests/net/ovpn/tcp_peers.txt @@ -0,0 +1,5 @@ +1 5.5.5.2 +2 5.5.5.3 +3 5.5.5.4 +4 5.5.5.5 +5 5.5.5.6 diff --git a/tools/testing/selftests/net/ovpn/test-chachapoly.sh b/tools/testing/selftests/net/ovpn/test-chachapoly.sh new file mode 100755 index 0000000000000000000000000000000000000000..79788f10d33b9682ed27590a48d136eb50b2202c --- /dev/null +++ b/tools/testing/selftests/net/ovpn/test-chachapoly.sh @@ -0,0 +1,9 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +ALG="chachapoly" + +source test.sh diff --git a/tools/testing/selftests/net/ovpn/test-float.sh b/tools/testing/selftests/net/ovpn/test-float.sh new file mode 100755 index 0000000000000000000000000000000000000000..93e1b729861d6b3f9f3f2e19d84e524c293ee3cf --- /dev/null +++ b/tools/testing/selftests/net/ovpn/test-float.sh @@ -0,0 +1,9 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +FLOAT="1" + +source test.sh diff --git a/tools/testing/selftests/net/ovpn/test-tcp.sh b/tools/testing/selftests/net/ovpn/test-tcp.sh new file mode 100755 index 0000000000000000000000000000000000000000..7542f595cc5696396513ed029cb96fe3b922d0e4 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/test-tcp.sh @@ -0,0 +1,9 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +PROTO="TCP" + +source test.sh diff --git a/tools/testing/selftests/net/ovpn/test.sh b/tools/testing/selftests/net/ovpn/test.sh new file mode 100755 index 0000000000000000000000000000000000000000..addbc1f68168473cf4a49e1b34f2bd27091f090d --- /dev/null +++ b/tools/testing/selftests/net/ovpn/test.sh @@ -0,0 +1,182 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020-2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +#set -x +set -e + +UDP_PEERS_FILE=${UDP_PEERS_FILE:-udp_peers.txt} +TCP_PEERS_FILE=${TCP_PEERS_FILE:-tcp_peers.txt} +OVPN_CLI=${OVPN_CLI:-./ovpn-cli} +ALG=${ALG:-aes} +PROTO=${PROTO:-UDP} +FLOAT=${FLOAT:-0} + +create_ns() { + ip netns add peer${1} +} + +setup_ns() { + MODE="P2P" + + if [ ${1} -eq 0 ]; then + MODE="MP" + for p in $(seq 1 ${NUM_PEERS}); do + ip link add veth${p} netns peer0 type veth peer name veth${p} netns peer${p} + + ip -n peer0 addr add 10.10.${p}.1/24 dev veth${p} + ip -n peer0 link set veth${p} up + + ip -n peer${p} addr add 10.10.${p}.2/24 dev veth${p} + ip -n peer${p} link set veth${p} up + done + fi + + ip netns exec peer${1} ${OVPN_CLI} new_iface tun${1} $MODE + ip -n peer${1} addr add ${2} dev tun${1} + ip -n peer${1} link set tun${1} up +} + +add_peer() { + if [ "${PROTO}" == "UDP" ]; then + if [ ${1} -eq 0 ]; then + ip netns exec peer0 ${OVPN_CLI} new_multi_peer tun0 1 ${UDP_PEERS_FILE} + + for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 1 0 ${ALG} 0 \ + data64.key + done + else + ip netns exec peer${1} ${OVPN_CLI} new_peer tun${1} ${1} 1 10.10.${1}.1 1 + ip netns exec peer${1} ${OVPN_CLI} new_key tun${1} ${1} 1 0 ${ALG} 1 \ + data64.key + fi + else + if [ ${1} -eq 0 ]; then + (ip netns exec peer0 ${OVPN_CLI} listen tun0 1 ${TCP_PEERS_FILE} && { + for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 1 0 \ + ${ALG} 0 data64.key + done + }) & + sleep 5 + else + ip netns exec peer${1} ${OVPN_CLI} connect tun${1} ${1} 10.10.${1}.1 1 \ + data64.key + fi + fi +} + +cleanup() { + # first test peers disconnect on down event + for p in $(seq 0 10); do + ip -n peer${p} link set tun${p} down 2>/dev/null || true + done + for p in $(seq 1 10); do + ip -n peer0 link del veth${p} 2>/dev/null || true + done + for p in $(seq 0 10); do + ip netns exec peer${p} ${OVPN_CLI} del_iface tun${p} 2>/dev/null || true + ip netns del peer${p} 2>/dev/null || true + done +} + +if [ "${PROTO}" == "UDP" ]; then + NUM_PEERS=${NUM_PEERS:-$(wc -l ${UDP_PEERS_FILE} | awk '{print $1}')} +else + NUM_PEERS=${NUM_PEERS:-$(wc -l ${TCP_PEERS_FILE} | awk '{print $1}')} +fi + +cleanup + +modprobe -q ovpn || true + +for p in $(seq 0 ${NUM_PEERS}); do + create_ns ${p} +done + +for p in $(seq 0 ${NUM_PEERS}); do + setup_ns ${p} 5.5.5.$((${p} + 1))/24 +done + +for p in $(seq 0 ${NUM_PEERS}); do + add_peer ${p} +done + +for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} set_peer tun0 ${p} 60 120 + ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 60 120 +done + +for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ping -qfc 1000 -w 5 5.5.5.$((${p} + 1)) +done + +if [ "$FLOAT" == "1" ]; then + # make clients float.. + for p in $(seq 1 ${NUM_PEERS}); do + ip -n peer${p} addr del 10.10.${p}.2/24 dev veth${p} + ip -n peer${p} addr add 10.10.${p}.3/24 dev veth${p} + done + for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer${p} ping -qfc 1000 -w 5 5.5.5.1 + done +fi + +ip netns exec peer0 iperf3 -1 -s & +sleep 1 +ip netns exec peer1 iperf3 -Z -t 3 -c 5.5.5.1 + +echo "Adding secondary key and then swap:" +for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 2 1 ${ALG} 0 data64.key + ip netns exec peer${p} ${OVPN_CLI} new_key tun${p} ${p} 2 1 ${ALG} 1 data64.key + ip netns exec peer${p} ${OVPN_CLI} swap_keys tun${p} ${p} +done + +sleep 1 +echo "Querying all peers:" +ip netns exec peer0 ${OVPN_CLI} get_peer tun0 +ip netns exec peer1 ${OVPN_CLI} get_peer tun1 + +echo "Querying peer 1:" +ip netns exec peer0 ${OVPN_CLI} get_peer tun0 1 + +echo "Querying non-existent peer 10:" +ip netns exec peer0 ${OVPN_CLI} get_peer tun0 10 || true + +echo "Deleting peer 1:" +ip netns exec peer0 ${OVPN_CLI} del_peer tun0 1 +ip netns exec peer1 ${OVPN_CLI} del_peer tun1 1 + +echo "Querying keys:" +for p in $(seq 2 ${NUM_PEERS}); do + ip netns exec peer${p} ${OVPN_CLI} get_key tun${p} ${p} 1 + ip netns exec peer${p} ${OVPN_CLI} get_key tun${p} ${p} 2 +done + +echo "Deleting keys:" +for p in $(seq 2 ${NUM_PEERS}); do + ip netns exec peer${p} ${OVPN_CLI} del_key tun${p} ${p} 1 + ip netns exec peer${p} ${OVPN_CLI} del_key tun${p} ${p} 2 +done + +echo "Setting timeout to 5s MP:" +for p in $(seq 2 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} set_peer tun0 ${p} 5 5 || true + ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 0 0 +done +# wait for peers to timeout +sleep 7 + +echo "Setting timeout to 5s P2P:" +for p in $(seq 2 ${NUM_PEERS}); do + ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 5 5 +done +sleep 7 + +cleanup + +modprobe -r ovpn || true diff --git a/tools/testing/selftests/net/ovpn/udp_peers.txt b/tools/testing/selftests/net/ovpn/udp_peers.txt new file mode 100644 index 0000000000000000000000000000000000000000..32f14bd9347a63e58438311b6d880b9fef768aa2 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/udp_peers.txt @@ -0,0 +1,5 @@ +1 10.10.1.2 1 5.5.5.2 +2 10.10.2.2 1 5.5.5.3 +3 10.10.3.2 1 5.5.5.4 +4 10.10.4.2 1 5.5.5.5 +5 10.10.5.2 1 5.5.5.6