OpenVPN is a userspace software existing since around 2005 that allows users to create secure tunnels.

So far OpenVPN has implemented all operations in userspace, which implies several back and forth between kernel and user land in order to process packets (encapsulate/decapsulate, encrypt/decrypt, rerouting..).

With `ovpn` we intend to move the fast path (data channel) entirely in kernel space and thus improve user measured throughput over the tunnel.

`ovpn` is implemented as a simple virtual network device driver, that can be manipulated by means of the standard RTNL APIs. A device of kind `ovpn` allows only IPv4/6 traffic and can be of type: * P2P (peer-to-peer): any packet sent over the interface will be encapsulated and transmitted to the other side (typical OpenVPN client or peer-to-peer behaviour); * P2MP (point-to-multipoint): packets sent over the interface are transmitted to peers based on existing routes (typical OpenVPN server behaviour).

After the interface has been created, OpenVPN in userspace can configure it using a new Netlink API. Specifically it is possible to manage peers and their keys.

The OpenVPN control channel is multiplexed over the same transport socket by means of OP codes. Anything that is not DATA_V2 (OpenVPN OP code for data traffic) is sent to userspace and handled there. This way the `ovpn` codebase is kept as compact as possible while focusing on handling data traffic only (fast path).

Any OpenVPN control feature (like cipher negotiation, TLS handshake, rekeying, etc.) is still fully handled by the userspace process.

When userspace establishes a new connection with a peer, it first performs the handshake and then passes the socket to the `ovpn` kernel module, which takes ownership. From this moment on `ovpn` will handle data traffic for the new peer. When control packets are received on the link, they are forwarded to userspace through the same transport socket they were received on, as userspace is still listening to them.

Some events (like peer deletion) are sent to a Netlink multicast group.

Although it wasn't easy to convince the community, `ovpn` implements only a limited number of the data-channel features supported by the userspace program.

Each feature that made it to `ovpn` was attentively vetted to avoid carrying too much legacy along with us (and to give a clear cut to old and probalby-not-so-useful features).

Notably, only encryption using AEAD ciphers (specifically ChaCha20Poly1305 and AES-GCM) was implemented. Supporting any other cipher out there was not deemed useful.

Both UDP and TCP sockets ae supported.

As explained above, in case of P2MP mode, OpenVPN will use the main system routing table to decide which packet goes to which peer. This implies that no routing table was re-implemented in the `ovpn` kernel module.

This kernel module can be enabled by selecting the CONFIG_OVPN entry in the networking drivers section.

NOTE: this first patch introduces the very basic framework only. Features are then added patch by patch, however, although each patch will compile and possibly not break at runtime, only after having applied the full set it is expected to see the ovpn module fully working.

Cc: steffen.klassert@secunet.com Cc: antony.antony@secunet.com Signed-off-by: Antonio Quartulli antonio@openvpn.net --- MAINTAINERS | 8 ++++ drivers/net/Kconfig | 14 ++++++ drivers/net/Makefile | 1 + drivers/net/ovpn/Makefile | 11 +++++ drivers/net/ovpn/io.c | 22 ++++++++++ drivers/net/ovpn/io.h | 15 +++++++ drivers/net/ovpn/main.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/main.h | 15 +++++++ include/uapi/linux/udp.h | 1 + 9 files changed, 196 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS index e71d066dc919404231446f8adfb291494e392883..0f02c9e1664fddb5ad45232e46b02c42aa27f1b6 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17448,6 +17448,14 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs.git F: Documentation/filesystems/overlayfs.rst F: fs/overlayfs/

+OPENVPN DATA CHANNEL OFFLOAD +M: Antonio Quartulli antonio@openvpn.net +L: openvpn-devel@lists.sourceforge.net (moderated for non-subscribers) +L: netdev@vger.kernel.org +S: Maintained +T: git https://github.com/OpenVPN/linux-kernel-ovpn.git +F: drivers/net/ovpn/ + P54 WIRELESS DRIVER M: Christian Lamparter chunkeey@googlemail.com L: linux-wireless@vger.kernel.org diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 9920b3a68ed1582ab3af1cf9d4f6ae7bfd68ba7a..0055bcd2356c70bd9cfd8a944f549817dab8154f 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -115,6 +115,20 @@ config WIREGUARD_DEBUG

Say N here unless you know what you're doing.

+config OVPN + tristate "OpenVPN data channel offload" + depends on NET && INET + select NET_UDP_TUNNEL + select DST_CACHE + select CRYPTO + 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. + config EQUALIZER tristate "EQL (serial line load balancing) support" help diff --git a/drivers/net/Makefile b/drivers/net/Makefile index 13743d0e83b5fde479e9b30ad736be402d880dee..5152b3330e28da7eaec821018a26c973bb33ce0c 100644 --- a/drivers/net/Makefile +++ b/drivers/net/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_IPVLAN) += ipvlan/ obj-$(CONFIG_IPVTAP) += ipvlan/ obj-$(CONFIG_DUMMY) += dummy.o obj-$(CONFIG_WIREGUARD) += wireguard/ +obj-$(CONFIG_OVPN) += ovpn/ obj-$(CONFIG_EQUALIZER) += eql.o obj-$(CONFIG_IFB) += ifb.o obj-$(CONFIG_MACSEC) += macsec.o diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile new file mode 100644 index 0000000000000000000000000000000000000000..53fb197027d787d6683e9056d3d341abf6ed38e4 --- /dev/null +++ b/drivers/net/ovpn/Makefile @@ -0,0 +1,11 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# ovpn -- OpenVPN data channel offload in kernel space +# +# Copyright (C) 2020-2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +obj-$(CONFIG_OVPN) := ovpn.o +ovpn-y += main.o +ovpn-y += io.o diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c new file mode 100644 index 0000000000000000000000000000000000000000..ad3813419c33cbdfe7e8ad6f5c8b444a3540a69f --- /dev/null +++ b/drivers/net/ovpn/io.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2019-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#include <linux/netdevice.h> +#include <linux/skbuff.h> + +#include "io.h" + +/* Send user data to the network + */ +netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev) +{ + skb_tx_error(skb); + kfree_skb(skb); + return NET_XMIT_DROP; +} diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h new file mode 100644 index 0000000000000000000000000000000000000000..aa259be66441f7b0262f39da12d6c3dce0a9b24c --- /dev/null +++ b/drivers/net/ovpn/io.h @@ -0,0 +1,15 @@ +/* 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_OVPN_H_ +#define _NET_OVPN_OVPN_H_ + +netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev); + +#endif /* _NET_OVPN_OVPN_H_ */ diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c new file mode 100644 index 0000000000000000000000000000000000000000..2a9a8e11c5111eb36fab1fb47d6c4c6dfdf56a78 --- /dev/null +++ b/drivers/net/ovpn/main.c @@ -0,0 +1,109 @@ +// 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/module.h> +#include <linux/netdevice.h> +#include <linux/version.h> +#include <net/rtnetlink.h> + +#include "main.h" +#include "io.h" + +/* Driver info */ +#define DRV_DESCRIPTION "OpenVPN data channel offload (ovpn)" +#define DRV_COPYRIGHT "(C) 2020-2024 OpenVPN, Inc." + +/** + * ovpn_dev_is_valid - check if the netdevice is of type 'ovpn' + * @dev: the interface to check + * + * Return: whether the netdevice is of type 'ovpn' + */ +bool ovpn_dev_is_valid(const struct net_device *dev) +{ + return dev->netdev_ops->ndo_start_xmit == ovpn_net_xmit; +} + +static struct rtnl_link_ops ovpn_link_ops = { + .kind = "ovpn", + .netns_refund = false, + .dellink = unregister_netdevice_queue, +}; + +static int ovpn_netdev_notifier_call(struct notifier_block *nb, + unsigned long state, void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + + if (!ovpn_dev_is_valid(dev)) + return NOTIFY_DONE; + + switch (state) { + case NETDEV_REGISTER: + /* add device to internal list for later destruction upon + * unregistration + */ + break; + case NETDEV_UNREGISTER: + /* can be delivered multiple times, so check registered flag, + * then destroy the interface + */ + break; + case NETDEV_POST_INIT: + case NETDEV_GOING_DOWN: + case NETDEV_DOWN: + case NETDEV_UP: + case NETDEV_PRE_UP: + default: + return NOTIFY_DONE; + } + + return NOTIFY_OK; +} + +static struct notifier_block ovpn_netdev_notifier = { + .notifier_call = ovpn_netdev_notifier_call, +}; + +static int __init ovpn_init(void) +{ + int err = register_netdevice_notifier(&ovpn_netdev_notifier); + + if (err) { + pr_err("ovpn: can't register netdevice notifier: %d\n", err); + return err; + } + + err = rtnl_link_register(&ovpn_link_ops); + if (err) { + pr_err("ovpn: can't register rtnl link ops: %d\n", err); + goto unreg_netdev; + } + + return 0; + +unreg_netdev: + unregister_netdevice_notifier(&ovpn_netdev_notifier); + return err; +} + +static __exit void ovpn_cleanup(void) +{ + rtnl_link_unregister(&ovpn_link_ops); + unregister_netdevice_notifier(&ovpn_netdev_notifier); + + rcu_barrier(); +} + +module_init(ovpn_init); +module_exit(ovpn_cleanup); + +MODULE_DESCRIPTION(DRV_DESCRIPTION); +MODULE_AUTHOR(DRV_COPYRIGHT); +MODULE_LICENSE("GPL"); diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h new file mode 100644 index 0000000000000000000000000000000000000000..a3215316c49bfcdf2496590bac878f145b8b27fd --- /dev/null +++ b/drivers/net/ovpn/main.h @@ -0,0 +1,15 @@ +/* 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_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/include/uapi/linux/udp.h b/include/uapi/linux/udp.h index 1a0fe8b151fb33543429d1f59167a9021b458e20..f9f8ffddfd0c8b5583bb99b1406c77ddfcbc69d1 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 */

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 | 387 ++++++++++++++++++++++++++++++++++ MAINTAINERS | 2 + drivers/net/ovpn/Makefile | 2 + drivers/net/ovpn/main.c | 15 +- drivers/net/ovpn/netlink-gen.c | 224 ++++++++++++++++++++ drivers/net/ovpn/netlink-gen.h | 42 ++++ drivers/net/ovpn/netlink.c | 158 ++++++++++++++ drivers/net/ovpn/netlink.h | 15 ++ drivers/net/ovpn/ovpnstruct.h | 21 ++ include/uapi/linux/ovpn.h | 116 ++++++++++ 10 files changed, 981 insertions(+), 1 deletion(-)

diff --git a/Documentation/netlink/specs/ovpn.yaml b/Documentation/netlink/specs/ovpn.yaml new file mode 100644 index 0000000000000000000000000000000000000000..36983f293ecbd59532114808a20737005e91ad72 --- /dev/null +++ b/Documentation/netlink/specs/ovpn.yaml @@ -0,0 +1,387 @@ +# 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 + value-start: 0 + entries: [ none, aes-gcm, chacha20-poly1305 ] + - + type: enum + name: del-peer-reason + value-start: 0 + entries: [ teardown, userspace, expired, transport-error, transport-disconnect ] + - + type: enum + name: key-slot + value-start: 0 + entries: [ primary, secondary ] + - + type: enum + name: mode + value-start: 0 + entries: [ p2p, mp ] + +attribute-sets: + - + name: peer + attributes: + - + name: id + type: u32 + doc: | + The unique ID of the peer. To be used to identify peers during + operations + 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: 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. 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. 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 actua 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 that is being created + - + name: mode + type: u32 + enum: mode + doc: | + Oper mode instructing an interface to act as Point2Point or + MultiPoint + - + 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: dev-new + attribute-set: ovpn + flags: [ admin-perm ] + doc: Create a new interface of type ovpn + do: + request: + attributes: + - ifname + - mode + reply: + attributes: + - ifname + - ifindex + - + name: dev-del + attribute-set: ovpn + flags: [ admin-perm ] + doc: Delete existing interface of type ovpn + do: + pre: ovpn-nl-pre-doit + post: ovpn-nl-post-doit + request: + attributes: + - ifindex + - + 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-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-new + 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 0f02c9e1664fddb5ad45232e46b02c42aa27f1b6..f753060d4e2467a786778ddd4f835861a603ce02 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17455,6 +17455,8 @@ L: netdev@vger.kernel.org S: Maintained T: git https://github.com/OpenVPN/linux-kernel-ovpn.git F: drivers/net/ovpn/ +F: include/uapi/linux/ovpn.h +F: Documentation/netlink/spec/ovpn.yaml

P54 WIRELESS DRIVER M: Christian Lamparter chunkeey@googlemail.com diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index 53fb197027d787d6683e9056d3d341abf6ed38e4..201dc001419f1d99ae95c0ee0f96e68f8a4eac16 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -9,3 +9,5 @@ obj-$(CONFIG_OVPN) := ovpn.o ovpn-y += main.o ovpn-y += io.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 2a9a8e11c5111eb36fab1fb47d6c4c6dfdf56a78..0274ddddbcd25080d7f85347f79aad0259771508 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -7,12 +7,16 @@ * James Yonan james@openvpn.net */

+#include <linux/genetlink.h> #include <linux/module.h> #include <linux/netdevice.h> #include <linux/version.h> #include <net/rtnetlink.h> +#include <uapi/linux/ovpn.h>

+#include "ovpnstruct.h" #include "main.h" +#include "netlink.h" #include "io.h"

/* Driver info */ @@ -31,7 +35,7 @@ bool ovpn_dev_is_valid(const struct net_device *dev) }

static struct rtnl_link_ops ovpn_link_ops = { - .kind = "ovpn", + .kind = OVPN_FAMILY_NAME, .netns_refund = false, .dellink = unregister_netdevice_queue, }; @@ -86,8 +90,16 @@ 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; @@ -95,6 +107,7 @@ 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/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c new file mode 100644 index 0000000000000000000000000000000000000000..9912706a2d68282e7d483404002cd0eeb1140ba6 --- /dev/null +++ b/drivers/net/ovpn/netlink-gen.c @@ -0,0 +1,224 @@ +// 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_U32, }, + [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_U16, 1), + [OVPN_A_PEER_SOCKET] = { .type = NLA_U32, }, + [OVPN_A_PEER_VPN_IPV4] = { .type = NLA_U32, }, + [OVPN_A_PEER_VPN_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_LOCAL_IPV4] = { .type = NLA_U32, }, + [OVPN_A_PEER_LOCAL_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_LOCAL_PORT] = NLA_POLICY_MIN(NLA_U16, 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, 4), + [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_DEV_NEW - do */ +static const struct nla_policy ovpn_dev_new_nl_policy[OVPN_A_MODE + 1] = { + [OVPN_A_IFNAME] = { .type = NLA_NUL_STRING, }, + [OVPN_A_MODE] = NLA_POLICY_MAX(NLA_U32, 1), +}; + +/* OVPN_CMD_DEV_DEL - do */ +static const struct nla_policy ovpn_dev_del_nl_policy[OVPN_A_IFINDEX + 1] = { + [OVPN_A_IFINDEX] = { .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_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_DEV_NEW, + .doit = ovpn_nl_dev_new_doit, + .policy = ovpn_dev_new_nl_policy, + .maxattr = OVPN_A_MODE, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = OVPN_CMD_DEV_DEL, + .pre_doit = ovpn_nl_pre_doit, + .doit = ovpn_nl_dev_del_doit, + .post_doit = ovpn_nl_post_doit, + .policy = ovpn_dev_del_nl_policy, + .maxattr = OVPN_A_IFINDEX, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .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_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..1b7aeb80af1091d5fe968c886fb019ba6f9a19a8 --- /dev/null +++ b/drivers/net/ovpn/netlink-gen.h @@ -0,0 +1,42 @@ +/* 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_dev_new_doit(struct sk_buff *skb, struct genl_info *info); +int ovpn_nl_dev_del_doit(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_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..7b6b4d03b845eeb8654e37ac3495e8172ac3f291 --- /dev/null +++ b/drivers/net/ovpn/netlink.c @@ -0,0 +1,158 @@ +// 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 "io.h" +#include "netlink.h" +#include "netlink-gen.h" + +MODULE_ALIAS_GENL_FAMILY(OVPN_FAMILY_NAME); + +/** + * ovpn_get_dev_from_attrs - retrieve 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 netdevice, if found, or an error otherwise + */ +static struct net_device * +ovpn_get_dev_from_attrs(struct net *net, const struct genl_info *info) +{ + 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]); + + dev = dev_get_by_index(net, ifindex); + if (!dev) { + NL_SET_ERR_MSG_MOD(info->extack, + "ifindex does not match any interface"); + return ERR_PTR(-ENODEV); + } + + if (!ovpn_dev_is_valid(dev)) + goto err_put_dev; + + return dev; + +err_put_dev: + netdev_put(dev, NULL); + + 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); +} + +int ovpn_nl_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb, + struct genl_info *info) +{ + struct net *net = genl_info_net(info); + struct net_device *dev = ovpn_get_dev_from_attrs(net, info); + + if (IS_ERR(dev)) + return PTR_ERR(dev); + + info->user_ptr[0] = netdev_priv(dev); + + return 0; +} + +void ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb, + struct genl_info *info) +{ + struct ovpn_struct *ovpn = info->user_ptr[0]; + + if (ovpn) + netdev_put(ovpn->dev, NULL); +} + +int ovpn_nl_dev_new_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +int ovpn_nl_dev_del_doit(struct sk_buff *skb, struct genl_info *info) +{ + return -EOPNOTSUPP; +} + +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_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..ff248cad1401d00c5bf0aadf9341e40d0a4aee4b --- /dev/null +++ b/drivers/net/ovpn/ovpnstruct.h @@ -0,0 +1,21 @@ +/* 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_ + +/** + * struct ovpn_struct - per ovpn interface state + * @dev: the actual netdev representing the tunnel + */ +struct ovpn_struct { + struct net_device *dev; +}; + +#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..adf4cafd9624308cc7bf1935bba55fb38bb6ba8c --- /dev/null +++ b/include/uapi/linux/ovpn.h @@ -0,0 +1,116 @@ +/* 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_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_mode { + OVPN_MODE_P2P, + OVPN_MODE_MP, +}; + +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_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_MODE, + OVPN_A_PEER, + OVPN_A_KEYCONF, + + __OVPN_A_MAX, + OVPN_A_MAX = (__OVPN_A_MAX - 1) +}; + +enum { + OVPN_CMD_DEV_NEW = 1, + OVPN_CMD_DEV_DEL, + OVPN_CMD_PEER_NEW, + OVPN_CMD_PEER_SET, + OVPN_CMD_PEER_GET, + OVPN_CMD_PEER_DEL, + OVPN_CMD_PEER_DEL_NTF, + OVPN_CMD_KEY_NEW, + 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 */

Allow userspace to create and destroy an interface using netlink commands.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/main.h | 2 ++ drivers/net/ovpn/netlink.c | 59 ++++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h index 4dfcba9deb590bbf119f51a40dff1517fe227b22..c664d9c655734263fcf58dd8f2fa5446565a29cf 100644 --- a/drivers/net/ovpn/main.h +++ b/drivers/net/ovpn/main.h @@ -10,6 +10,8 @@ #ifndef _NET_OVPN_MAIN_H_ #define _NET_OVPN_MAIN_H_

+#define OVPN_DEFAULT_IFNAME "ovpn%d" + struct net_device *ovpn_iface_create(const char *name, enum ovpn_mode mode, struct net *net); void ovpn_iface_destruct(struct ovpn_struct *ovpn); diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c index 7b6b4d03b845eeb8654e37ac3495e8172ac3f291..6e60591d605dde19c6bbd47ef0e90e522776688c 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -7,6 +7,7 @@ */

#include <linux/netdevice.h> +#include <linux/rtnetlink.h> #include <net/genetlink.h>

#include <uapi/linux/ovpn.h> @@ -84,12 +85,66 @@ void ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb,

int ovpn_nl_dev_new_doit(struct sk_buff *skb, struct genl_info *info) { - return -EOPNOTSUPP; + const char *ifname = OVPN_DEFAULT_IFNAME; + enum ovpn_mode mode = OVPN_MODE_P2P; + struct net_device *dev; + struct sk_buff *msg; + void *hdr; + + if (info->attrs[OVPN_A_IFNAME]) + ifname = nla_data(info->attrs[OVPN_A_IFNAME]); + + if (info->attrs[OVPN_A_MODE]) { + mode = nla_get_u32(info->attrs[OVPN_A_MODE]); + pr_debug("ovpn: setting device (%s) mode: %u\n", ifname, mode); + } + + dev = ovpn_iface_create(ifname, mode, genl_info_net(info)); + if (IS_ERR(dev)) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "error while creating interface: %ld", + PTR_ERR(dev)); + return PTR_ERR(dev); + } + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + hdr = genlmsg_iput(msg, info); + if (!hdr) { + nlmsg_free(msg); + return -ENOBUFS; + } + + if (nla_put_string(msg, OVPN_A_IFNAME, dev->name)) { + genlmsg_cancel(msg, hdr); + nlmsg_free(msg); + return -EMSGSIZE; + } + + if (nla_put_u32(msg, OVPN_A_IFINDEX, dev->ifindex)) { + genlmsg_cancel(msg, hdr); + nlmsg_free(msg); + return -EMSGSIZE; + } + + genlmsg_end(msg, hdr); + + return genlmsg_reply(msg, info); }

int ovpn_nl_dev_del_doit(struct sk_buff *skb, struct genl_info *info) { - return -EOPNOTSUPP; + struct ovpn_struct *ovpn = info->user_ptr[0]; + + rtnl_lock(); + ovpn_iface_destruct(ovpn); + unregister_netdevice(ovpn->dev); + netdev_put(ovpn->dev, NULL); + rtnl_unlock(); + + return 0; }

int ovpn_nl_peer_new_doit(struct sk_buff *skb, struct genl_info *info)

An ovpn_peer object holds the whole status of a remote peer (regardless whether it is a server or a client).

This includes status for crypto, tx/rx buffers, napi, etc.

Only support for one peer is introduced (P2P mode). Multi peer support is introduced with a later patch.

Along with the ovpn_peer, also the ovpn_bind object is introcued as the two are strictly related. An ovpn_bind object wraps a sockaddr representing the local coordinates being used to talk to a specific peer.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/Makefile | 2 + drivers/net/ovpn/bind.c | 58 +++++++ drivers/net/ovpn/bind.h | 117 ++++++++++++++ drivers/net/ovpn/main.c | 12 ++ drivers/net/ovpn/main.h | 2 + drivers/net/ovpn/ovpnstruct.h | 7 + drivers/net/ovpn/peer.c | 355 ++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/peer.h | 82 ++++++++++ 8 files changed, 635 insertions(+)

diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index 201dc001419f1d99ae95c0ee0f96e68f8a4eac16..ce13499b3e1775a7f2a9ce16c6cb0aa088f93685 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -7,7 +7,9 @@ # Author: Antonio Quartulli antonio@openvpn.net

obj-$(CONFIG_OVPN) := ovpn.o +ovpn-y += bind.o ovpn-y += main.o ovpn-y += io.o ovpn-y += netlink.o ovpn-y += netlink-gen.o +ovpn-y += peer.o diff --git a/drivers/net/ovpn/bind.c b/drivers/net/ovpn/bind.c new file mode 100644 index 0000000000000000000000000000000000000000..b4d2ccec2ceddf43bc445b489cc62a578ef0ad0a --- /dev/null +++ b/drivers/net/ovpn/bind.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel offload + * + * Copyright (C) 2012-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#include <linux/netdevice.h> +#include <linux/socket.h> + +#include "ovpnstruct.h" +#include "bind.h" +#include "peer.h" + +/** + * ovpn_bind_from_sockaddr - retrieve binding matching sockaddr + * @ss: the sockaddr to match + * + * Return: the bind matching the passed sockaddr if found, NULL otherwise + */ +struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *ss) +{ + struct ovpn_bind *bind; + size_t sa_len; + + if (ss->ss_family == AF_INET) + sa_len = sizeof(struct sockaddr_in); + else if (ss->ss_family == AF_INET6) + sa_len = sizeof(struct sockaddr_in6); + else + return ERR_PTR(-EAFNOSUPPORT); + + bind = kzalloc(sizeof(*bind), GFP_ATOMIC); + if (unlikely(!bind)) + return ERR_PTR(-ENOMEM); + + memcpy(&bind->remote, ss, sa_len); + + return bind; +} + +/** + * ovpn_bind_reset - assign new binding to peer + * @peer: the peer whose binding has to be replaced + * @new: the new bind to assign + */ +void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *new) +{ + struct ovpn_bind *old; + + spin_lock_bh(&peer->lock); + old = rcu_replace_pointer(peer->bind, new, true); + spin_unlock_bh(&peer->lock); + + kfree_rcu(old, rcu); +} diff --git a/drivers/net/ovpn/bind.h b/drivers/net/ovpn/bind.h new file mode 100644 index 0000000000000000000000000000000000000000..859213d5040deb36c416eafcf5c6ab31c4d52c7a --- /dev/null +++ b/drivers/net/ovpn/bind.h @@ -0,0 +1,117 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2012-2024 OpenVPN, Inc. + * + * Author: James Yonan james@openvpn.net + * Antonio Quartulli antonio@openvpn.net + */ + +#ifndef _NET_OVPN_OVPNBIND_H_ +#define _NET_OVPN_OVPNBIND_H_ + +#include <net/ip.h> +#include <linux/in.h> +#include <linux/in6.h> +#include <linux/rcupdate.h> +#include <linux/skbuff.h> +#include <linux/spinlock.h> + +struct ovpn_peer; + +/** + * union ovpn_sockaddr - basic transport layer address + * @in4: IPv4 address + * @in6: IPv6 address + */ +union ovpn_sockaddr { + struct sockaddr_in in4; + struct sockaddr_in6 in6; +}; + +/** + * struct ovpn_bind - remote peer binding + * @remote: the remote peer sockaddress + * @local: local endpoint used to talk to the peer + * @local.ipv4: local IPv4 used to talk to the peer + * @local.ipv6: local IPv6 used to talk to the peer + * @rcu: used to schedule RCU cleanup job + */ +struct ovpn_bind { + union ovpn_sockaddr remote; /* remote sockaddr */ + + union { + struct in_addr ipv4; + struct in6_addr ipv6; + } local; + + struct rcu_head rcu; +}; + +/** + * skb_protocol_to_family - translate skb->protocol to AF_INET or AF_INET6 + * @skb: the packet sk_buff to inspect + * + * Return: AF_INET, AF_INET6 or 0 in case of unknown protocol + */ +static inline unsigned short skb_protocol_to_family(const struct sk_buff *skb) +{ + switch (skb->protocol) { + case htons(ETH_P_IP): + return AF_INET; + case htons(ETH_P_IPV6): + return AF_INET6; + default: + return 0; + } +} + +/** + * ovpn_bind_skb_src_match - match packet source with binding + * @bind: the binding to match + * @skb: the packet to match + * + * Return: true if the packet source matches the remote peer sockaddr + * in the binding + */ +static inline bool ovpn_bind_skb_src_match(const struct ovpn_bind *bind, + const struct sk_buff *skb) +{ + const unsigned short family = skb_protocol_to_family(skb); + const union ovpn_sockaddr *remote; + + if (unlikely(!bind)) + return false; + + remote = &bind->remote; + + if (unlikely(remote->in4.sin_family != family)) + return false; + + switch (family) { + case AF_INET: + if (unlikely(remote->in4.sin_addr.s_addr != ip_hdr(skb)->saddr)) + return false; + + if (unlikely(remote->in4.sin_port != udp_hdr(skb)->source)) + return false; + break; + case AF_INET6: + if (unlikely(!ipv6_addr_equal(&remote->in6.sin6_addr, + &ipv6_hdr(skb)->saddr))) + return false; + + if (unlikely(remote->in6.sin6_port != udp_hdr(skb)->source)) + return false; + break; + default: + return false; + } + + return true; +} + +struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *sa); +void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *bind); + +#endif /* _NET_OVPN_OVPNBIND_H_ */ diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c index 87d49b83107aa9c276c5b200ac919965379c99be..4522f2f8978614c96d529f807bd2cf32a44f8216 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -11,6 +11,7 @@ #include <linux/module.h> #include <linux/netdevice.h> #include <linux/inetdevice.h> +//#include <linux/rcupdate.h> #include <linux/version.h> #include <net/ip.h> #include <net/rtnetlink.h> @@ -22,6 +23,7 @@ #include "netlink.h" #include "io.h" #include "packet.h" +#include "peer.h"

/* Driver info */ #define DRV_DESCRIPTION "OpenVPN data channel offload (ovpn)" @@ -38,12 +40,18 @@ static void ovpn_struct_init(struct net_device *dev, enum ovpn_mode mode)

ovpn->dev = dev; ovpn->mode = mode; + spin_lock_init(&ovpn->lock); }

static void ovpn_struct_free(struct net_device *net) { }

+static int ovpn_net_init(struct net_device *dev) +{ + return 0; +} + static int ovpn_net_open(struct net_device *dev) { /* ovpn keeps the carrier always on to avoid losing IP or route @@ -64,6 +72,7 @@ static int ovpn_net_stop(struct net_device *dev) }

static const struct net_device_ops ovpn_netdev_ops = { + .ndo_init = ovpn_net_init, .ndo_open = ovpn_net_open, .ndo_stop = ovpn_net_stop, .ndo_start_xmit = ovpn_net_xmit, @@ -184,6 +193,9 @@ void ovpn_iface_destruct(struct ovpn_struct *ovpn) netif_carrier_off(ovpn->dev);

ovpn->registered = false; + + if (ovpn->mode == OVPN_MODE_P2P) + ovpn_peer_release_p2p(ovpn); }

static int ovpn_netdev_notifier_call(struct notifier_block *nb, diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h index c664d9c655734263fcf58dd8f2fa5446565a29cf..7e957248af6ab44ad8555318c74cc94be99844ab 100644 --- a/drivers/net/ovpn/main.h +++ b/drivers/net/ovpn/main.h @@ -24,4 +24,6 @@ bool ovpn_dev_is_valid(const struct net_device *dev); #define OVPN_HEAD_ROOM ALIGN(16 + SKB_HEADER_LEN, 4) #define OVPN_MAX_PADDING 16

+#define OVPN_QUEUE_LEN 1024 + #endif /* _NET_OVPN_MAIN_H_ */ diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h index ee05b8a2c61d7c5887e80c7f79e15a1336d99644..25f4837b798b1a2c9b11763dfb5b44e8ec337e6f 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -10,19 +10,26 @@ #ifndef _NET_OVPN_OVPNSTRUCT_H_ #define _NET_OVPN_OVPNSTRUCT_H_

+#include <net/net_trackers.h> #include <uapi/linux/ovpn.h>

/** * struct ovpn_struct - per ovpn interface state * @dev: the actual netdev representing the tunnel + * @dev_tracker: reference tracker for associated dev * @registered: whether dev is still registered with netdev or not * @mode: device operation mode (i.e. p2p, mp, ..) + * @lock: protect this object + * @peer: in P2P mode, this is the only remote peer * @dev_list: entry for the module wide device list */ struct ovpn_struct { struct net_device *dev; + netdevice_tracker dev_tracker; bool registered; enum ovpn_mode mode; + spinlock_t lock; /* protect writing to the ovpn_struct object */ + struct ovpn_peer __rcu *peer; struct list_head dev_list; };

diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c new file mode 100644 index 0000000000000000000000000000000000000000..23ded79eb7748a10b683d9aaa351b361ae79847e --- /dev/null +++ b/drivers/net/ovpn/peer.c @@ -0,0 +1,355 @@ +// 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/skbuff.h> +#include <linux/list.h> +#include <linux/workqueue.h> + +#include "ovpnstruct.h" +#include "bind.h" +#include "io.h" +#include "main.h" +#include "netlink.h" +#include "peer.h" + +/** + * ovpn_peer_new - allocate and initialize a new peer object + * @ovpn: the openvpn instance inside which the peer should be created + * @id: the ID assigned to this peer + * + * Return: a pointer to the new peer on success or an error code otherwise + */ +struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *ovpn, u32 id) +{ + struct ovpn_peer *peer; + int ret; + + /* alloc and init peer object */ + peer = kzalloc(sizeof(*peer), GFP_KERNEL); + if (!peer) + return ERR_PTR(-ENOMEM); + + peer->id = id; + peer->halt = false; + peer->ovpn = ovpn; + + peer->vpn_addrs.ipv4.s_addr = htonl(INADDR_ANY); + peer->vpn_addrs.ipv6 = in6addr_any; + + RCU_INIT_POINTER(peer->bind, NULL); + spin_lock_init(&peer->lock); + kref_init(&peer->refcount); + + ret = dst_cache_init(&peer->dst_cache, GFP_KERNEL); + if (ret < 0) { + netdev_err(ovpn->dev, "%s: cannot initialize dst cache\n", + __func__); + kfree(peer); + return ERR_PTR(ret); + } + + netdev_hold(ovpn->dev, &ovpn->dev_tracker, GFP_KERNEL); + + return peer; +} + +/** + * ovpn_peer_release - release peer private members + * @peer: the peer to release + */ +static void ovpn_peer_release(struct ovpn_peer *peer) +{ + ovpn_bind_reset(peer, NULL); + + dst_cache_destroy(&peer->dst_cache); +} + +/** + * ovpn_peer_release_kref - callback for kref_put + * @kref: the kref object belonging to the peer + */ +void ovpn_peer_release_kref(struct kref *kref) +{ + struct ovpn_peer *peer = container_of(kref, struct ovpn_peer, refcount); + + ovpn_peer_release(peer); + netdev_put(peer->ovpn->dev, &peer->ovpn->dev_tracker); + kfree_rcu(peer, rcu); +} + +/** + * ovpn_peer_skb_to_sockaddr - fill sockaddr with skb source address + * @skb: the packet to extract data from + * @ss: the sockaddr to fill + * + * Return: true on success or false otherwise + */ +static bool ovpn_peer_skb_to_sockaddr(struct sk_buff *skb, + struct sockaddr_storage *ss) +{ + struct sockaddr_in6 *sa6; + struct sockaddr_in *sa4; + + ss->ss_family = skb_protocol_to_family(skb); + switch (ss->ss_family) { + case AF_INET: + sa4 = (struct sockaddr_in *)ss; + sa4->sin_family = AF_INET; + sa4->sin_addr.s_addr = ip_hdr(skb)->saddr; + sa4->sin_port = udp_hdr(skb)->source; + break; + case AF_INET6: + sa6 = (struct sockaddr_in6 *)ss; + sa6->sin6_family = AF_INET6; + sa6->sin6_addr = ipv6_hdr(skb)->saddr; + sa6->sin6_port = udp_hdr(skb)->source; + break; + default: + return false; + } + + return true; +} + +/** + * ovpn_peer_transp_match - check if sockaddr and peer binding match + * @peer: the peer to get the binding from + * @ss: the sockaddr to match + * + * Return: true if sockaddr and binding match or false otherwise + */ +static bool ovpn_peer_transp_match(const struct ovpn_peer *peer, + const struct sockaddr_storage *ss) +{ + struct ovpn_bind *bind = rcu_dereference(peer->bind); + struct sockaddr_in6 *sa6; + struct sockaddr_in *sa4; + + if (unlikely(!bind)) + return false; + + if (ss->ss_family != bind->remote.in4.sin_family) + return false; + + switch (ss->ss_family) { + case AF_INET: + sa4 = (struct sockaddr_in *)ss; + if (sa4->sin_addr.s_addr != bind->remote.in4.sin_addr.s_addr) + return false; + if (sa4->sin_port != bind->remote.in4.sin_port) + return false; + break; + case AF_INET6: + sa6 = (struct sockaddr_in6 *)ss; + if (!ipv6_addr_equal(&sa6->sin6_addr, + &bind->remote.in6.sin6_addr)) + return false; + if (sa6->sin6_port != bind->remote.in6.sin6_port) + return false; + break; + default: + return false; + } + + return true; +} + +/** + * ovpn_peer_get_by_transp_addr_p2p - get peer by transport address in a P2P + * instance + * @ovpn: the openvpn instance to search + * @ss: the transport socket address + * + * Return: the peer if found or NULL otherwise + */ +static struct ovpn_peer * +ovpn_peer_get_by_transp_addr_p2p(struct ovpn_struct *ovpn, + struct sockaddr_storage *ss) +{ + struct ovpn_peer *tmp, *peer = NULL; + + rcu_read_lock(); + tmp = rcu_dereference(ovpn->peer); + if (likely(tmp && ovpn_peer_transp_match(tmp, ss) && + ovpn_peer_hold(tmp))) + peer = tmp; + rcu_read_unlock(); + + return peer; +} + +/** + * ovpn_peer_get_by_transp_addr - retrieve peer by transport address + * @ovpn: the openvpn instance to search + * @skb: the skb to retrieve the source transport address from + * + * Return: a pointer to the peer if found or NULL otherwise + */ +struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn, + struct sk_buff *skb) +{ + struct ovpn_peer *peer = NULL; + struct sockaddr_storage ss = { 0 }; + + if (unlikely(!ovpn_peer_skb_to_sockaddr(skb, &ss))) + return NULL; + + if (ovpn->mode == OVPN_MODE_P2P) + peer = ovpn_peer_get_by_transp_addr_p2p(ovpn, &ss); + + return peer; +} + +/** + * ovpn_peer_get_by_id_p2p - get peer by ID in a P2P instance + * @ovpn: the openvpn instance to search + * @peer_id: the ID of the peer to find + * + * Return: the peer if found or NULL otherwise + */ +static struct ovpn_peer *ovpn_peer_get_by_id_p2p(struct ovpn_struct *ovpn, + u32 peer_id) +{ + struct ovpn_peer *tmp, *peer = NULL; + + rcu_read_lock(); + tmp = rcu_dereference(ovpn->peer); + if (likely(tmp && tmp->id == peer_id && ovpn_peer_hold(tmp))) + peer = tmp; + rcu_read_unlock(); + + return peer; +} + +/** + * ovpn_peer_get_by_id - retrieve peer by ID + * @ovpn: the openvpn instance to search + * @peer_id: the unique peer identifier to match + * + * Return: a pointer to the peer if found or NULL otherwise + */ +struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id) +{ + struct ovpn_peer *peer = NULL; + + if (ovpn->mode == OVPN_MODE_P2P) + peer = ovpn_peer_get_by_id_p2p(ovpn, peer_id); + + return peer; +} + +/** + * ovpn_peer_add_p2p - add peer to related tables in a P2P 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_p2p(struct ovpn_struct *ovpn, struct ovpn_peer *peer) +{ + struct ovpn_peer *tmp; + + spin_lock_bh(&ovpn->lock); + /* in p2p mode it is possible to have a single peer only, therefore the + * old one is released and substituted by the new one + */ + tmp = rcu_dereference_protected(ovpn->peer, + lockdep_is_held(&ovpn->lock)); + if (tmp) { + tmp->delete_reason = OVPN_DEL_PEER_REASON_TEARDOWN; + ovpn_peer_put(tmp); + } + + rcu_assign_pointer(ovpn->peer, peer); + spin_unlock_bh(&ovpn->lock); + + return 0; +} + +/** + * ovpn_peer_add - add peer to the related tables + * @ovpn: the openvpn instance the peer belongs to + * @peer: the peer object to add + * + * Assume refcounter was increased by caller + * + * Return: 0 on success or a negative error code otherwise + */ +int ovpn_peer_add(struct ovpn_struct *ovpn, struct ovpn_peer *peer) +{ + switch (ovpn->mode) { + case OVPN_MODE_P2P: + return ovpn_peer_add_p2p(ovpn, peer); + default: + return -EOPNOTSUPP; + } +} + +/** + * ovpn_peer_del_p2p - delete peer from related tables in a P2P 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_p2p(struct ovpn_peer *peer, + enum ovpn_del_peer_reason reason) + __must_hold(&peer->ovpn->lock) +{ + struct ovpn_peer *tmp; + + tmp = rcu_dereference_protected(peer->ovpn->peer, + lockdep_is_held(&peer->ovpn->lock)); + if (tmp != peer) { + DEBUG_NET_WARN_ON_ONCE(1); + if (tmp) + ovpn_peer_put(tmp); + + return -ENOENT; + } + + tmp->delete_reason = reason; + RCU_INIT_POINTER(peer->ovpn->peer, NULL); + ovpn_peer_put(tmp); + + return 0; +} + +/** + * ovpn_peer_release_p2p - release peer upon P2P device teardown + * @ovpn: the instance being torn down + */ +void ovpn_peer_release_p2p(struct ovpn_struct *ovpn) +{ + struct ovpn_peer *tmp; + + spin_lock_bh(&ovpn->lock); + tmp = rcu_dereference_protected(ovpn->peer, + lockdep_is_held(&ovpn->lock)); + if (tmp) + ovpn_peer_del_p2p(tmp, OVPN_DEL_PEER_REASON_TEARDOWN); + spin_unlock_bh(&ovpn->lock); +} + +/** + * ovpn_peer_del - delete peer from related tables + * @peer: the peer object to delete + * @reason: reason for deleting peer (will be sent to userspace) + * + * Return: 0 on success or a negative error code otherwise + */ +int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason) +{ + switch (peer->ovpn->mode) { + case OVPN_MODE_P2P: + return ovpn_peer_del_p2p(peer, reason); + default: + return -EOPNOTSUPP; + } +} diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h new file mode 100644 index 0000000000000000000000000000000000000000..6c51959363c78f22e5bbeecbfe65dc90c67e86cc --- /dev/null +++ b/drivers/net/ovpn/peer.h @@ -0,0 +1,82 @@ +/* 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_OVPNPEER_H_ +#define _NET_OVPN_OVPNPEER_H_ + +#include "bind.h" + +#include <net/dst_cache.h> +#include <uapi/linux/ovpn.h> + +/** + * struct ovpn_peer - the main remote peer object + * @ovpn: main openvpn instance this peer belongs to + * @id: unique identifier + * @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 + * @dst_cache: cache for dst_entry used to send to peer + * @bind: remote peer binding + * @halt: true if ovpn_peer_mark_delete was called + * @delete_reason: why peer was deleted (i.e. timeout, transport error, ..) + * @lock: protects binding to peer (bind) + * @refcount: reference counter + * @rcu: used to free peer in an RCU safe way + * @delete_work: deferred cleanup work, used to notify userspace + */ +struct ovpn_peer { + struct ovpn_struct *ovpn; + u32 id; + struct { + struct in_addr ipv4; + struct in6_addr ipv6; + } vpn_addrs; + struct dst_cache dst_cache; + struct ovpn_bind __rcu *bind; + bool halt; + enum ovpn_del_peer_reason delete_reason; + spinlock_t lock; /* protects bind */ + struct kref refcount; + struct rcu_head rcu; + struct work_struct delete_work; +}; + +/** + * ovpn_peer_hold - increase reference counter + * @peer: the peer whose counter should be increased + * + * Return: true if the counter was increased or false if it was zero already + */ +static inline bool ovpn_peer_hold(struct ovpn_peer *peer) +{ + return kref_get_unless_zero(&peer->refcount); +} + +void ovpn_peer_release_kref(struct kref *kref); + +/** + * ovpn_peer_put - decrease reference counter + * @peer: the peer whose counter should be decreased + */ +static inline void ovpn_peer_put(struct ovpn_peer *peer) +{ + kref_put(&peer->refcount, ovpn_peer_release_kref); +} + +struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *ovpn, u32 id); +int ovpn_peer_add(struct ovpn_struct *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_struct *ovpn); + +struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn, + struct sk_buff *skb); +struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id); + +#endif /* _NET_OVPN_OVPNPEER_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/ovpn/io.c | 137 +++++++++++++++++++++++++++- drivers/net/ovpn/peer.c | 37 +++++++- drivers/net/ovpn/peer.h | 5 ++ drivers/net/ovpn/skb.h | 51 +++++++++++ drivers/net/ovpn/udp.c | 232 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/udp.h | 8 ++ 6 files changed, 467 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index ad3813419c33cbdfe7e8ad6f5c8b444a3540a69f..dfd2c90c56842374b7fb1c8bead061a76272441e 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -9,14 +9,149 @@

#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" + +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->ovpn, 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_struct *ovpn, struct sk_buff *skb, + struct ovpn_peer *peer) +{ + struct sk_buff *curr, *next; + + if (likely(!peer)) + /* 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", + ovpn->dev->name); + dev_core_stats_tx_dropped_inc(ovpn->dev); + goto drop; + } + + /* 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); + } + + /* skb passed over, no need to free */ + skb = NULL; +drop: + if (likely(peer)) + ovpn_peer_put(peer); + kfree_skb_list(skb); +}

/* Send user data to the network */ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev) { + struct ovpn_struct *ovpn = netdev_priv(dev); + struct sk_buff *segments, *curr, *next; + struct sk_buff_head skb_list; + __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)) { + net_err_ratelimited("%s: dropping malformed payload packet\n", + dev->name); + dev_core_stats_tx_dropped_inc(ovpn->dev); + 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 packet: %d\n", + dev->name, ret); + dev_core_stats_tx_dropped_inc(ovpn->dev); + 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\n", + dev->name); + dev_core_stats_tx_dropped_inc(ovpn->dev); + continue; + } + + __skb_queue_tail(&skb_list, curr); + } + skb_list.prev->next = NULL; + + ovpn_send(ovpn, skb_list.next, NULL); + + return NETDEV_TX_OK; + +drop: 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 23ded79eb7748a10b683d9aaa351b361ae79847e..6bde4bd9395b08ea3c25c58cb99e09afdf8ad097 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -9,7 +9,6 @@

#include <linux/skbuff.h> #include <linux/list.h> -#include <linux/workqueue.h>

#include "ovpnstruct.h" #include "bind.h" @@ -65,8 +64,10 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *ovpn, u32 id) */ static void ovpn_peer_release(struct ovpn_peer *peer) { - ovpn_bind_reset(peer, NULL); + if (peer->sock) + ovpn_socket_put(peer->sock);

+ ovpn_bind_reset(peer, NULL); dst_cache_destroy(&peer->dst_cache); }

@@ -244,6 +245,38 @@ struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *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_struct *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 diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 6c51959363c78f22e5bbeecbfe65dc90c67e86cc..37de5aff54a8df9adc449d1346b251b1feab0b1c 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -11,6 +11,7 @@ #define _NET_OVPN_OVPNPEER_H_

#include "bind.h" +#include "socket.h"

#include <net/dst_cache.h> #include <uapi/linux/ovpn.h> @@ -22,6 +23,7 @@ * @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 * @halt: true if ovpn_peer_mark_delete was called @@ -38,6 +40,7 @@ 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; bool halt; @@ -78,5 +81,7 @@ void ovpn_peer_release_p2p(struct ovpn_struct *ovpn); struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn, struct sk_buff *skb); struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id); +struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *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..e070fe6f448c0b7a9631394ebef4554f6348ef44 --- /dev/null +++ b/drivers/net/ovpn/skb.h @@ -0,0 +1,51 @@ +/* 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/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) + 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 c10474d252e19a0626d17a6f5dd328a5e5811551..d26d7566e9c8dfe91fa77f49c34fb179a9fb2239 100644 --- a/drivers/net/ovpn/udp.c +++ b/drivers/net/ovpn/udp.c @@ -7,14 +7,246 @@ */

#include <linux/netdevice.h> +#include <linux/inetdevice.h> #include <linux/socket.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 + * @ovpn: the openvpn instance + * @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_struct *ovpn, 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; + bind->local.ipv4.s_addr = 0; + 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; + bind->local.ipv4.s_addr = 0; + 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", + ovpn->dev->name, &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 + * @ovpn: the openvpn instance + * @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_struct *ovpn, 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; + bind->local.ipv6 = in6addr_any; + 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", + ovpn->dev->name, &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 + * @ovpn: the openvpn instance + * @bind: the binding related to 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_struct *ovpn, struct ovpn_bind *bind, + struct dst_cache *cache, struct sock *sk, + struct sk_buff *skb) +{ + 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; + + switch (bind->remote.in4.sin_family) { + case AF_INET: + ret = ovpn_udp4_output(ovpn, bind, cache, sk, skb); + break; +#if IS_ENABLED(CONFIG_IPV6) + case AF_INET6: + ret = ovpn_udp6_output(ovpn, bind, cache, sk, skb); + break; +#endif + default: + ret = -EAFNOSUPPORT; + break; + } + + return ret; +} + +/** + * ovpn_udp_send_skb - prepare skb and send it over via UDP + * @ovpn: the openvpn instance + * @peer: the destination peer + * @skb: the packet to send + */ +void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer, + struct sk_buff *skb) +{ + struct ovpn_bind *bind; + unsigned int pkt_len; + struct socket *sock; + int ret = -1; + + skb->dev = 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\n", __func__); + goto out; + } + + rcu_read_lock(); + /* get binding */ + bind = rcu_dereference(peer->bind); + if (unlikely(!bind)) { + net_warn_ratelimited("%s: no bind for remote peer\n", __func__); + goto out_unlock; + } + + /* crypto layer -> transport (UDP) */ + pkt_len = skb->len; + ret = ovpn_udp_output(ovpn, bind, &peer->dst_cache, sock->sk, skb); + +out_unlock: + rcu_read_unlock(); +out: + if (unlikely(ret < 0)) { + dev_core_stats_tx_dropped_inc(ovpn->dev); + kfree_skb(skb); + return; + } + + dev_sw_netstats_tx_add(ovpn->dev, 1, pkt_len); +} + /** * 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 f2507f8f2c71ea9d5e5ac5446801e2d56f86700f..e60f8cd2b4ac8f910aabcf8ed546af59d6ca4be4 100644 --- a/drivers/net/ovpn/udp.h +++ b/drivers/net/ovpn/udp.h @@ -9,9 +9,17 @@ #ifndef _NET_OVPN_UDP_H_ #define _NET_OVPN_UDP_H_

+#include <linux/skbuff.h> +#include <net/sock.h> + +struct ovpn_peer; struct ovpn_struct; +struct sk_buff; struct socket;

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

+void ovpn_udp_send_skb(struct ovpn_struct *ovpn, 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/ovpn/Makefile | 3 + drivers/net/ovpn/crypto.c | 153 ++++++++++++++++++ drivers/net/ovpn/crypto.h | 136 ++++++++++++++++ drivers/net/ovpn/crypto_aead.c | 354 +++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/crypto_aead.h | 31 ++++ drivers/net/ovpn/io.c | 140 ++++++++++++++-- drivers/net/ovpn/io.h | 3 + drivers/net/ovpn/packet.h | 2 +- drivers/net/ovpn/peer.c | 29 ++++ drivers/net/ovpn/peer.h | 6 + drivers/net/ovpn/pktid.c | 130 +++++++++++++++ drivers/net/ovpn/pktid.h | 87 ++++++++++ drivers/net/ovpn/proto.h | 31 ++++ drivers/net/ovpn/skb.h | 11 +- 14 files changed, 1104 insertions(+), 12 deletions(-)

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..f1f7510e2f735e367f96eb4982ba82c9af3c8bfc --- /dev/null +++ b/drivers/net/ovpn/crypto.c @@ -0,0 +1,153 @@ +// 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 "packet.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..61de855d23649598a6e5a34447a35ed9620dfde1 --- /dev/null +++ b/drivers/net/ovpn/crypto.h @@ -0,0 +1,136 @@ +/* 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_ + +/* 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; + struct ovpn_nonce_tail nonce_tail_xmit; + struct ovpn_nonce_tail nonce_tail_recv; + + 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..97134ac679c67a3d44a0bf49c2ddf058fd7c0e99 --- /dev/null +++ b/drivers/net/ovpn/crypto_aead.c @@ -0,0 +1,354 @@ +// 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 "packet.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 + +static int ovpn_aead_encap_overhead(const struct ovpn_crypto_key_slot *ks) +{ + return OVPN_OP_SIZE_V2 + /* OP header size */ + 4 + /* 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); + const unsigned int head_size = ovpn_aead_encap_overhead(ks); + struct aead_request *req; + struct sk_buff *trailer; + struct scatterlist *sg; + u8 iv[NONCE_SIZE]; + int nfrags, ret; + u32 pktid, op; + + /* 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, after adding network header and encryption overhead + */ + if (unlikely(skb_cow_head(skb, OVPN_HEAD_ROOM + head_size))) + 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)->ctx = kmalloc(sizeof(*ovpn_skb_cb(skb)->ctx), + GFP_ATOMIC); + if (unlikely(!ovpn_skb_cb(skb)->ctx)) + return -ENOMEM; + + sg = ovpn_skb_cb(skb)->ctx->sg; + + /* sg table: + * 0: op, wire nonce (AD, len=OVPN_OP_SIZE_V2+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)) + return -EINVAL; + + /* 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)) { + kfree(ovpn_skb_cb(skb)->ctx); + return ret; + } + + /* 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, NONCE_WIRE_SIZE); + memcpy(skb->data, iv, 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_OP_SIZE_V2); + BUILD_BUG_ON(sizeof(op) != OVPN_OP_SIZE_V2); + *((__force __be32 *)skb->data) = htonl(op); + + /* AEAD Additional data */ + sg_set_buf(sg, skb->data, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE); + + req = aead_request_alloc(ks->encrypt, GFP_ATOMIC); + if (unlikely(!req)) { + kfree(ovpn_skb_cb(skb)->ctx); + return -ENOMEM; + } + + /* 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 - head_size, iv); + aead_request_set_ad(req, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE); + + ovpn_skb_cb(skb)->ctx->peer = peer; + ovpn_skb_cb(skb)->ctx->req = req; + ovpn_skb_cb(skb)->ctx->ks = ks; + + /* encrypt it */ + return crypto_aead_encrypt(req); +} + +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; + unsigned int sg_len; + u8 iv[NONCE_SIZE]; + + payload_offset = OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE + tag_size; + payload_len = skb->len - payload_offset; + + /* 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)->ctx = kmalloc(sizeof(*ovpn_skb_cb(skb)->ctx), + GFP_ATOMIC); + if (unlikely(!ovpn_skb_cb(skb)->ctx)) + return -ENOMEM; + + sg = ovpn_skb_cb(skb)->ctx->sg; + + /* sg table: + * 0: op, wire nonce (AD, len=OVPN_OP_SIZE_V2+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_OP_SIZE_V2 + 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)) { + kfree(ovpn_skb_cb(skb)->ctx); + return -EINVAL; + } + + /* 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_OP_SIZE_V2, NONCE_WIRE_SIZE); + memcpy(iv + NONCE_WIRE_SIZE, ks->nonce_tail_recv.u8, + sizeof(struct ovpn_nonce_tail)); + + req = aead_request_alloc(ks->decrypt, GFP_ATOMIC); + if (unlikely(!req)) { + kfree(ovpn_skb_cb(skb)->ctx); + return -ENOMEM; + } + + /* 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, NONCE_WIRE_SIZE + OVPN_OP_SIZE_V2); + + ovpn_skb_cb(skb)->ctx->payload_offset = payload_offset; + ovpn_skb_cb(skb)->ctx->peer = peer; + ovpn_skb_cb(skb)->ctx->req = req; + ovpn_skb_cb(skb)->ctx->ks = ks; + + /* decrypt it */ + return crypto_aead_decrypt(req); +} + +/* 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) != NONCE_SIZE) { + pr_err("%s IV size must be %d\n", title, 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 = "gcm(aes)"; + break; + case OVPN_CIPHER_ALG_CHACHA20_POLY1305: + alg_name = "rfc7539(chacha20,poly1305)"; + break; + default: + return ERR_PTR(-EOPNOTSUPP); + } + + if (sizeof(struct ovpn_nonce_tail) != kc->encrypt.nonce_tail_size || + sizeof(struct ovpn_nonce_tail) != kc->decrypt.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.u8, kc->encrypt.nonce_tail, + sizeof(struct ovpn_nonce_tail)); + memcpy(ks->nonce_tail_recv.u8, kc->decrypt.nonce_tail, + sizeof(struct ovpn_nonce_tail)); + + /* 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 78449b52a2f8f710107d2493299c6aca9a2cb2ce..a75aa301b99e6abff04d5cb289b26b5979906ae5 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 +16,8 @@ #include "ovpnstruct.h" #include "peer.h" #include "io.h" +#include "crypto.h" +#include "crypto_aead.h" #include "netlink.h" #include "proto.h" #include "udp.h" @@ -57,33 +60,133 @@ 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 = NULL; + unsigned int payload_offset = 0; + struct ovpn_peer *peer = NULL; + struct sk_buff *skb = data; + __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; + + /* crypto is done, cleanup skb CB and its members */ + if (likely(ovpn_skb_cb(skb)->ctx)) { + payload_offset = ovpn_skb_cb(skb)->ctx->payload_offset; + ks = ovpn_skb_cb(skb)->ctx->ks; + peer = ovpn_skb_cb(skb)->ctx->peer; + + aead_request_free(ovpn_skb_cb(skb)->ctx->req); + kfree(ovpn_skb_cb(skb)->ctx); + ovpn_skb_cb(skb)->ctx = NULL; + }

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

+ /* PID sits after the op */ + pid = (__force __be32 *)(skb->data + OVPN_OP_SIZE_V2); + ret = ovpn_pktid_recv(&ks->pid_recv, ntohl(*pid), 0); + if (unlikely(ret < 0)) { + net_err_ratelimited("%s: PKT ID RX error: %d\n", + peer->ovpn->dev->name, 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", + peer->ovpn->dev->name, peer->id); + goto drop; + } + + net_info_ratelimited("%s: unsupported protocol received from peer %u\n", + peer->ovpn->dev->name, 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_to_family(skb) == AF_INET6) + net_dbg_ratelimited("%s: RPF dropped packet from peer %u, src: %pI6c\n", + peer->ovpn->dev->name, peer->id, + &ipv6_hdr(skb)->saddr); + else + net_dbg_ratelimited("%s: RPF dropped packet from peer %u, src: %pI4\n", + peer->ovpn->dev->name, 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); }

/* pick next packet from RX queue, decrypt 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", + peer->ovpn->dev->name, peer->id, key_id); + dev_core_stats_rx_dropped_inc(peer->ovpn->dev); + kfree_skb(skb); + return; + } + + ovpn_skb_cb(skb)->ctx = NULL; + 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_peer *peer = NULL; + struct sk_buff *skb = data; + + /* encryption is happening asynchronously. This function will be + * called later by the crypto callback with a proper return value + */ + if (unlikely(ret == -EINPROGRESS)) + return; + + /* crypto is done, cleanup skb CB and its members */ + if (likely(ovpn_skb_cb(skb)->ctx)) { + peer = ovpn_skb_cb(skb)->ctx->peer; + + ovpn_crypto_key_slot_put(ovpn_skb_cb(skb)->ctx->ks); + aead_request_free(ovpn_skb_cb(skb)->ctx->req); + kfree(ovpn_skb_cb(skb)->ctx); + ovpn_skb_cb(skb)->ctx = NULL; + }

if (unlikely(ret < 0)) goto err; @@ -103,13 +206,29 @@ 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); 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\n", + peer->ovpn->dev->name); + return false; + } + + /* get primary key to be used for encrypting data */ + ks = ovpn_crypto_key_slot_primary(&peer->crypto); + if (unlikely(!ks)) { + net_warn_ratelimited("%s: error while retrieving primary key slot for peer %u\n", + peer->ovpn->dev->name, peer->id); + return false; + }

/* take a reference to the peer because the crypto code may run async. * ovpn_encrypt_post() will release it upon completion @@ -119,7 +238,8 @@ static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb) return false; }

- ovpn_encrypt_post(skb, 0); + ovpn_skb_cb(skb)->ctx = NULL; + 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 9667a0a470e0b4b427524fffb5b9b395007e5a2f..ad81dd86924689309b3299573575a1705eddaf99 100644 --- a/drivers/net/ovpn/io.h +++ b/drivers/net/ovpn/io.h @@ -14,4 +14,7 @@ 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/packet.h b/drivers/net/ovpn/packet.h index 7ed146f5932a25f448af6da58738a7eae81007fe..e14c9bf464f742e6d27fe3133dd175996970845e 100644 --- a/drivers/net/ovpn/packet.h +++ b/drivers/net/ovpn/packet.h @@ -10,7 +10,7 @@ #ifndef _NET_OVPN_PACKET_H_ #define _NET_OVPN_PACKET_H_

-/* When the OpenVPN protocol is ran in AEAD mode, use +/* When the OpenVPN protocol is run in AEAD mode, use * the OpenVPN packet ID as the AEAD nonce: * * 00000005 521c3b01 4308c041 diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index 6bde4bd9395b08ea3c25c58cb99e09afdf8ad097..212d1210bc564ae804899d7c3bf8c2231e732cf1 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_struct *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);

@@ -67,6 +70,7 @@ static void ovpn_peer_release(struct ovpn_peer *peer) if (peer->sock) ovpn_socket_put(peer->sock);

+ ovpn_crypto_state_release(&peer->crypto); ovpn_bind_reset(peer, NULL); dst_cache_destroy(&peer->dst_cache); } @@ -277,6 +281,31 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *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_struct *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 + */ + rcu_read_lock(); + match = (peer == rcu_dereference(ovpn->peer)); + rcu_read_unlock(); + } + + 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 37de5aff54a8df9adc449d1346b251b1feab0b1c..70d92cd5bd6348dd91956593d7d87224061b85d0 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -11,6 +11,8 @@ #define _NET_OVPN_OVPNPEER_H_

#include "bind.h" +#include "pktid.h" +#include "crypto.h" #include "socket.h"

#include <net/dst_cache.h> @@ -24,6 +26,7 @@ * @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 * @halt: true if ovpn_peer_mark_delete was called @@ -41,6 +44,7 @@ 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; bool halt; @@ -83,5 +87,7 @@ struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn, struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id); struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *ovpn, struct sk_buff *skb); +bool ovpn_peer_check_by_src(struct ovpn_struct *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..96dc876356706eb6e2104cf8291c1487b4441b1f --- /dev/null +++ b/drivers/net/ovpn/pktid.c @@ -0,0 +1,130 @@ +// 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 "packet.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..fe02f0667e1a88a8c866fe4da4e5cebfba9efbcf --- /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 "packet.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 struct ovpn_nonce_tail *nt, + unsigned char *dest) +{ + *(__force __be32 *)(dest) = htonl(pktid); + BUILD_BUG_ON(4 + sizeof(struct ovpn_nonce_tail) != NONCE_SIZE); + memcpy(dest + 4, nt->u8, sizeof(struct ovpn_nonce_tail)); +} + +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 69604cf26bbf82539ee5cd5a7ac9c23920f555de..32af6b8e574381fb719a1b3b9de3ae1071cc4846 100644 --- a/drivers/net/ovpn/proto.h +++ b/drivers/net/ovpn/proto.h @@ -72,4 +72,35 @@ static inline u32 ovpn_peer_id_from_skb(const struct sk_buff *skb, u16 offset) return ntohl(*(__be32 *)(skb->data + offset)) & OVPN_PEER_ID_MASK; }

+/** + * 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) +{ + return *skb->data & OVPN_KEY_ID_MASK; +} + +/** + * 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) +{ + const u8 op = (opcode << OVPN_OPCODE_SHIFT) | + (key_id & OVPN_KEY_ID_MASK); + + return (op << 24) | (peer_id & OVPN_PEER_ID_MASK); +} + #endif /* _NET_OVPN_OVPNPROTO_H_ */ diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h index e070fe6f448c0b7a9631394ebef4554f6348ef44..3f94efae20fb58772c1a4c47df5bae8bb11ad322 100644 --- a/drivers/net/ovpn/skb.h +++ b/drivers/net/ovpn/skb.h @@ -17,8 +17,17 @@ #include <linux/socket.h> #include <linux/types.h>

-struct ovpn_cb { +struct ovpn_cb_ctx { struct ovpn_peer *peer; + struct sk_buff *skb; + struct ovpn_crypto_key_slot *ks; + struct aead_request *req; + struct scatterlist sg[MAX_SKB_FRAGS + 2]; + unsigned int payload_offset; +}; + +struct ovpn_cb { + struct ovpn_cb_ctx *ctx; };

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

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 | 50 +++++++++++- drivers/net/ovpn/ovpnstruct.h | 19 +++++ drivers/net/ovpn/peer.c | 173 ++++++++++++++++++++++++++++++++++++++++-- drivers/net/ovpn/peer.h | 9 +++ 4 files changed, 241 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c index cb5cc3d4b5620f5a1e401e06e52e67c32e57aa78..7604f0970d3c283f8680f6800a125427999bb174 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -50,13 +50,53 @@ static void ovpn_struct_free(struct net_device *net) struct ovpn_struct *ovpn = netdev_priv(net);

gro_cells_destroy(&ovpn->gro_cells); + kfree(ovpn->peers); }

static int ovpn_net_init(struct net_device *dev) { struct ovpn_struct *ovpn = netdev_priv(dev); + struct in_device *dev_v4; + int i, err;

- return gro_cells_init(&ovpn->gro_cells, dev); + err = gro_cells_init(&ovpn->gro_cells, dev); + if (err) + return err; + + if (ovpn->mode == OVPN_MODE_MP) { + dev_v4 = __in_dev_get_rtnl(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(dev), SEND_REDIRECTS) = false; + } + + /* the peer container is fairly large, therefore we dynamically + * allocate it only when needed + */ + ovpn->peers = kzalloc(sizeof(*ovpn->peers), GFP_KERNEL); + if (!ovpn->peers) { + gro_cells_destroy(&ovpn->gro_cells); + return -ENOMEM; + } + + spin_lock_init(&ovpn->peers->lock); + + 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_net_open(struct net_device *dev) @@ -201,8 +241,14 @@ void ovpn_iface_destruct(struct ovpn_struct *ovpn)

ovpn->registered = false;

- if (ovpn->mode == OVPN_MODE_P2P) + switch (ovpn->mode) { + case OVPN_MODE_P2P: ovpn_peer_release_p2p(ovpn); + break; + default: + ovpn_peers_free(ovpn); + break; + } }

static int ovpn_netdev_notifier_call(struct notifier_block *nb, diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h index 65497ce115aa4be719ed03f89135a80b73f9ef9b..4373d1bbc4874dc2f1d1f1697e7b847ec2f486c9 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -14,6 +14,23 @@ #include <net/net_trackers.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) + * @lock: protects writes to peer tables + */ +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]; + + spinlock_t lock; /* protects writes to peer tables */ +}; + /** * struct ovpn_struct - per ovpn interface state * @dev: the actual netdev representing the tunnel @@ -21,6 +38,7 @@ * @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 * @dev_list: entry for the module wide device list * @gro_cells: pointer to the Generic Receive Offload cell @@ -31,6 +49,7 @@ struct ovpn_struct { bool registered; enum ovpn_mode mode; spinlock_t lock; /* protect writing to the ovpn_struct object */ + struct ovpn_peer_collection *peers; struct ovpn_peer __rcu *peer; struct list_head dev_list; struct gro_cells gro_cells; diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index 6d34c56a4a51ce407b20b6175e6140aafc4b4e33..3c6fbf99f696c18d8a2dbe169c7f6f5933fb71ac 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" @@ -65,13 +66,12 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *ovpn, u32 id) }

/** - * ovpn_peer_release - release peer private members - * @peer: the peer to release + * ovpn_peer_release_rcu - release peer private members + * @head: RCU head belonging to peer being released */ -static void ovpn_peer_release(struct ovpn_peer *peer) +static void ovpn_peer_release_rcu(struct rcu_head *head) { - if (peer->sock) - ovpn_socket_put(peer->sock); + struct ovpn_peer *peer = container_of(head, struct ovpn_peer, rcu);

ovpn_crypto_state_release(&peer->crypto); ovpn_bind_reset(peer, NULL); @@ -86,9 +86,10 @@ void ovpn_peer_release_kref(struct kref *kref) { struct ovpn_peer *peer = container_of(kref, struct ovpn_peer, refcount);

- ovpn_peer_release(peer); + if (peer->sock) + ovpn_socket_put(peer->sock); netdev_put(peer->ovpn->dev, &peer->ovpn->dev_tracker); - kfree_rcu(peer, rcu); + call_rcu(&peer->rcu, ovpn_peer_release_rcu); }

/** @@ -309,6 +310,89 @@ bool ovpn_peer_check_by_src(struct ovpn_struct *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_struct *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->peers->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->peers->lock); + return ret; +} + /** * ovpn_peer_add_p2p - add peer to related tables in a P2P instance * @ovpn: the instance to add the peer to @@ -349,6 +433,8 @@ static int ovpn_peer_add_p2p(struct ovpn_struct *ovpn, struct ovpn_peer *peer) int ovpn_peer_add(struct ovpn_struct *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: @@ -356,6 +442,51 @@ int ovpn_peer_add(struct ovpn_struct *ovpn, struct ovpn_peer *peer) } }

+/** + * ovpn_peer_unhash - remove peer reference from all hashtables + * @peer: the peer to remove + * @reason: the delete reason to attach to the peer + */ +static void ovpn_peer_unhash(struct ovpn_peer *peer, + enum ovpn_del_peer_reason reason) + __must_hold(&ovpn->peers->lock) +{ + 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); + + ovpn_peer_put(peer); + peer->delete_reason = reason; +} + +/** + * 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) + __must_hold(&peer->ovpn->peers->lock) +{ + struct ovpn_peer *tmp; + int ret = -ENOENT; + + tmp = ovpn_peer_get_by_id(peer->ovpn, peer->id); + if (tmp == peer) { + ovpn_peer_unhash(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 @@ -411,10 +542,36 @@ void ovpn_peer_release_p2p(struct ovpn_struct *ovpn) */ int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason) { + int ret; + switch (peer->ovpn->mode) { + case OVPN_MODE_MP: + spin_lock_bh(&peer->ovpn->peers->lock); + ret = ovpn_peer_del_mp(peer, reason); + spin_unlock_bh(&peer->ovpn->peers->lock); + return ret; case OVPN_MODE_P2P: - return ovpn_peer_del_p2p(peer, reason); + spin_lock_bh(&peer->ovpn->lock); + ret = ovpn_peer_del_p2p(peer, reason); + spin_unlock_bh(&peer->ovpn->lock); + return ret; default: return -EOPNOTSUPP; } } + +/** + * ovpn_peers_free - free all peers in the instance + * @ovpn: the instance whose peers should be released + */ +void ovpn_peers_free(struct ovpn_struct *ovpn) +{ + struct hlist_node *tmp; + struct ovpn_peer *peer; + int bkt; + + spin_lock_bh(&ovpn->peers->lock); + hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id) + ovpn_peer_unhash(peer, OVPN_DEL_PEER_REASON_TEARDOWN); + spin_unlock_bh(&ovpn->peers->lock); +} diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 86d4696b1529c45025b63d2973fc48ca81ca8f63..9481eb41742ca2a6c88ee0262dd448fd947614fd 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -30,6 +30,10 @@ * @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) @@ -62,6 +66,10 @@ 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 @@ -126,6 +134,7 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *ovpn, u32 id); int ovpn_peer_add(struct ovpn_struct *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_struct *ovpn); +void ovpn_peers_free(struct ovpn_struct *ovpn);

struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *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 | 188 ++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/peer.h | 15 ++++ drivers/net/ovpn/proto.h | 2 - 7 files changed, 290 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 985f8bba6f1355b9f164e53f11575fa104133d43..4e69f31382d2cb9ce4bc40f06cfbae47add5b5ba 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -26,6 +26,33 @@ #include "udp.h" #include "skb.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. */ @@ -103,6 +130,9 @@ void ovpn_decrypt_post(void *data, int ret) goto drop; }

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

@@ -119,6 +149,12 @@ 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", + peer->ovpn->dev->name, peer->id); + goto drop; + } + net_info_ratelimited("%s: unsupported protocol received from peer %u\n", peer->ovpn->dev->name, peer->id); goto drop; @@ -217,6 +253,10 @@ void ovpn_encrypt_post(void *data, int ret) /* no transport configured yet */ goto err; } + + /* keep track of last sent packet for keepalive */ + peer->last_sent = ktime_get_real_seconds(); + /* skb passed down the stack - don't free it */ skb = NULL; err: @@ -355,3 +395,40 @@ 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_struct *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, "%s: cannot hold peer reference for sending special packet\n", + __func__); + kfree_skb(skb); + return; + } + + ovpn_send(ovpn, skb, peer); +} diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h index ad81dd86924689309b3299573575a1705eddaf99..eb224114152c29f42aadf026212e8d278006b490 100644 --- a/drivers/net/ovpn/io.h +++ b/drivers/net/ovpn/io.h @@ -10,9 +10,14 @@ #ifndef _NET_OVPN_OVPN_H_ #define _NET_OVPN_OVPN_H_

+#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 7604f0970d3c283f8680f6800a125427999bb174..6048df5890c8fa46f3d91498903b4277a33f06db 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -43,6 +43,7 @@ static void ovpn_struct_init(struct net_device *dev, enum ovpn_mode mode) ovpn->dev = dev; ovpn->mode = mode; spin_lock_init(&ovpn->lock); + INIT_DELAYED_WORK(&ovpn->keepalive_work, ovpn_peer_keepalive_work); }

static void ovpn_struct_free(struct net_device *net) @@ -241,6 +242,8 @@ void ovpn_iface_destruct(struct ovpn_struct *ovpn)

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 4373d1bbc4874dc2f1d1f1697e7b847ec2f486c9..11c6c568246aafe64af32e1a1faf24583afe7ca6 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -42,6 +42,7 @@ struct ovpn_peer_collection { * @peer: in P2P mode, this is the only remote peer * @dev_list: entry for the module wide device list * @gro_cells: pointer to the Generic Receive Offload cell + * @keepalive_work: struct used to schedule keepalive periodic job */ struct ovpn_struct { struct net_device *dev; @@ -53,6 +54,7 @@ struct ovpn_struct { struct ovpn_peer __rcu *peer; struct list_head dev_list; 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 54d0a416f6f91513f42d5ecc1f1f65d688f3e908..dfaa4c7c012215b3dcd451b9bd1d7ffce9b1291c 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -22,6 +22,34 @@ #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, + "%s: scheduling keepalive for peer %u: interval=%u timeout=%u\n", + __func__, peer->id, interval, timeout); + + peer->keepalive_interval = interval; + peer->last_sent = now; + peer->keepalive_xmit_exp = now + interval; + + peer->keepalive_timeout = timeout; + 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); +} + /** * ovpn_peer_new - allocate and initialize a new peer object * @ovpn: the openvpn instance inside which the peer should be created @@ -76,6 +104,7 @@ static void ovpn_peer_release_rcu(struct rcu_head *head)

ovpn_crypto_state_release(&peer->crypto); ovpn_bind_reset(peer, NULL); + dst_cache_destroy(&peer->dst_cache); }

@@ -816,6 +845,19 @@ int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason) } }

+static int ovpn_peer_del_nolock(struct ovpn_peer *peer, + enum ovpn_del_peer_reason reason) +{ + switch (peer->ovpn->mode) { + case OVPN_MODE_MP: + return ovpn_peer_del_mp(peer, reason); + case OVPN_MODE_P2P: + return ovpn_peer_del_p2p(peer, reason); + default: + return -EOPNOTSUPP; + } +} + /** * ovpn_peers_free - free all peers in the instance * @ovpn: the instance whose peers should be released @@ -831,3 +873,149 @@ void ovpn_peers_free(struct ovpn_struct *ovpn) ovpn_peer_unhash(peer, OVPN_DEL_PEER_REASON_TEARDOWN); spin_unlock_bh(&ovpn->peers->lock); } + +static time64_t ovpn_peer_keepalive_work_single(struct ovpn_peer *peer, + time64_t now) +{ + time64_t next_run1, next_run2, delta; + 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; + delta = now - peer->last_recv; + if (delta < timeout) { + peer->keepalive_recv_exp = now + timeout - delta; + 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_del_nolock(peer, OVPN_DEL_PEER_REASON_EXPIRED); + return 0; + } + + /* check for peer keepalive */ + expired = false; + interval = peer->keepalive_interval; + delta = now - peer->last_sent; + if (delta < interval) { + peer->keepalive_xmit_exp = now + interval - delta; + 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); + ovpn_xmit_special(peer, ovpn_keepalive_message, + sizeof(ovpn_keepalive_message)); + } + + if (next_run1 < next_run2) + return next_run1; + + return next_run2; +} + +static time64_t ovpn_peer_keepalive_work_mp(struct ovpn_struct *ovpn, + time64_t now) +{ + time64_t tmp_next_run, next_run = 0; + struct hlist_node *tmp; + struct ovpn_peer *peer; + int bkt; + + spin_lock_bh(&ovpn->peers->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; + } + spin_unlock_bh(&ovpn->peers->lock); + + return next_run; +} + +static time64_t ovpn_peer_keepalive_work_p2p(struct ovpn_struct *ovpn, + time64_t now) +{ + struct ovpn_peer *peer; + time64_t next_run; + + spin_lock_bh(&ovpn->lock); + peer = rcu_dereference_protected(ovpn->peer, + lockdep_is_held(&ovpn->lock)); + next_run = ovpn_peer_keepalive_work_single(peer, now); + spin_unlock_bh(&ovpn->lock); + + 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_struct *ovpn = container_of(work, struct ovpn_struct, + keepalive_work.work); + time64_t next_run = 0, now = ktime_get_real_seconds(); + + 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; + } + + /* 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 9481eb41742ca2a6c88ee0262dd448fd947614fd..e0d8d1255b837b7ddfdcedc5a56e7e747f13e2c5 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -50,6 +50,12 @@ * @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 * @halt: true if ovpn_peer_mark_delete was called * @vpn_stats: per-peer in-VPN TX/RX stays * @link_stats: per-peer link/transport TX/RX stats @@ -98,6 +104,12 @@ 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; bool halt; struct ovpn_peer_stats vpn_stats; struct ovpn_peer_stats link_stats; @@ -144,4 +156,7 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *ovpn, bool ovpn_peer_check_by_src(struct ovpn_struct *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_ */ diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h index 32af6b8e574381fb719a1b3b9de3ae1071cc4846..0de8bafadc89ebb85ce40de95ef394588738a4ad 100644 --- a/drivers/net/ovpn/proto.h +++ b/drivers/net/ovpn/proto.h @@ -35,8 +35,6 @@ #define OVPN_OP_SIZE_V2 4 #define OVPN_PEER_ID_MASK 0x00FFFFFF #define OVPN_PEER_ID_UNDEF 0x00FFFFFF -/* first byte of keepalive message */ -#define OVPN_KEEPALIVE_FIRST_BYTE 0x2a /* first byte of exit message */ #define OVPN_EXPLICIT_EXIT_NOTIFY_FIRST_BYTE 0x28

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 | 10 ++-- drivers/net/ovpn/io.c | 9 ++++ drivers/net/ovpn/peer.c | 128 ++++++++++++++++++++++++++++++++++++++++++++++-- drivers/net/ovpn/peer.h | 2 + 4 files changed, 138 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ovpn/bind.c b/drivers/net/ovpn/bind.c index b4d2ccec2ceddf43bc445b489cc62a578ef0ad0a..d17d078c5730bf4336dc87f45cdba3f6b8cad770 100644 --- a/drivers/net/ovpn/bind.c +++ b/drivers/net/ovpn/bind.c @@ -47,12 +47,8 @@ struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *ss) * @new: the new bind to assign */ void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *new) + __must_hold(&peer->lock) { - struct ovpn_bind *old; - - 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 4e69f31382d2cb9ce4bc40f06cfbae47add5b5ba..8f2b4a85d20fbdb512de7ec312d391985e96b906 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -133,6 +133,15 @@ void ovpn_decrypt_post(void *data, int ret) /* keep track of last received authenticated packet for keepalive */ peer->last_recv = ktime_get_real_seconds();

+ if (peer->sock->sock->sk->sk_protocol == IPPROTO_UDP) { + /* check if this peer changed it's IP address and update + * state + */ + ovpn_peer_float(peer, skb); + /* update source endpoint for this peer */ + ovpn_peer_update_local_endpoint(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 f9d8f1d1827fe67dc4b4e0bba41a5b110bb90819..891cf2fa6a81b46ac764ad4fd50d4456fa7ce5bd 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -94,6 +94,128 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *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) + __must_hold(&peer->lock) +{ + struct ovpn_bind *bind; + size_t ip_len; + + /* 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 { + netdev_dbg(peer->ovpn->dev, "%s: invalid family for remote endpoint\n", + __func__); + kfree(bind); + return -EINVAL; + } + + memcpy(&bind->local, local_ip, ip_len); + } + + /* set binding */ + ovpn_bind_reset(peer, bind); + + return 0; +} + +#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ + typeof(_tbl) *__tbl = &(_tbl); \ + (&(*__tbl)[jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl)]); }) \ + +/** + * ovpn_peer_float - update remote endpoint for peer + * @peer: peer to update the remote endpoint for + * @skb: incoming packet to retrieve the source address (remote) from + */ +void ovpn_peer_float(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; + sa_family_t family; + size_t salen; + + rcu_read_lock(); + bind = rcu_dereference(peer->bind); + if (unlikely(!bind)) { + rcu_read_unlock(); + return; + } + + spin_lock_bh(&peer->lock); + if (likely(ovpn_bind_skb_src_match(bind, skb))) + goto unlock; + + family = skb_protocol_to_family(skb); + + if (bind->remote.in4.sin_family == family) + local_ip = (u8 *)&bind->local; + + switch (family) { + case AF_INET: + 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; + case AF_INET6: + 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); + break; + default: + goto unlock; + } + + netdev_dbg(peer->ovpn->dev, "%s: peer %d floated to %pIScp", __func__, + peer->id, &ss); + ovpn_peer_reset_sockaddr(peer, (struct sockaddr_storage *)&ss, + local_ip); + + /* 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->peers->lock); + /* 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, + &ss, salen); + hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead); + spin_unlock_bh(&peer->ovpn->peers->lock); + } +unlock: + spin_unlock_bh(&peer->lock); + rcu_read_unlock(); +} + /** * ovpn_peer_release_rcu - release peer private members * @head: RCU head belonging to peer being released @@ -103,7 +225,9 @@ static void ovpn_peer_release_rcu(struct rcu_head *head) struct ovpn_peer *peer = container_of(head, struct ovpn_peer, rcu);

ovpn_crypto_state_release(&peer->crypto); + spin_lock_bh(&peer->lock); ovpn_bind_reset(peer, NULL); + spin_unlock_bh(&peer->lock);

dst_cache_destroy(&peer->dst_cache); } @@ -188,10 +312,6 @@ static struct in6_addr ovpn_nexthop_from_skb6(struct sk_buff *skb) return rt->rt6i_gateway; }

-#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ - typeof(_tbl) *__tbl = &(_tbl); \ - (&(*__tbl)[jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl)]); }) \ - /** * ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address * @ovpn: the openvpn instance to search diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 6b66e169b33510a794f8f43dff757f0357e3e5de..ea1a014568c64d796bb18447ceb70e801bfaf3f2 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -162,4 +162,6 @@ 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_float(struct ovpn_peer *peer, struct sk_buff *skb); + #endif /* _NET_OVPN_OVPNPEER_H_ */

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

Userspace is expected to use these commands to create, destroy and rotate session keys for a specific peer.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/netlink.c | 210 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 207 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c index 29ff6023f9135b81a1d5fa42354398c70008aee5..c9cede9025505d1b69ec8eeeb60420d0a1647c82 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -744,19 +744,223 @@ 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_struct *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; + + peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]); + 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 = 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, "%s: new key installed (id=%u) for peer %u\n", + __func__, pkr.key.key_id, peer_id); +out: + ovpn_peer_put(peer); + return ret; }

int ovpn_nl_key_swap_doit(struct sk_buff *skb, struct genl_info *info) { - return -EOPNOTSUPP; + struct ovpn_struct *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_struct *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 (ret) + return ret; + + 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 e9cf847e99026e78eee4d65b62911671e8c2e407..b96c84fcc24921b2cd173ec2b6358b59eec72b39 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -963,6 +963,61 @@ 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(100, 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, dev_net(peer->ovpn->dev), msg, + 0, OVPN_NLGRP_PEERS, GFP_ATOMIC); + + 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 1ce31f0317cb3593a8edf95c43d03a0bddb0a58f..f201bcddb2d792e4f6b759d5e1fed42234aa1410 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -249,6 +249,7 @@ void ovpn_peer_release_kref(struct kref *kref)

if (peer->sock) ovpn_socket_put(peer->sock); + ovpn_nl_peer_del_notify(peer); call_rcu(&peer->rcu, ovpn_peer_release_rcu); }

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

It implementes the netlink API and can thus be integrated in any script for more automated testing.

Along with the tool, 2 scripts are added that perform basic functionality tests by means of network namespaces.

The scripts can be performed in sequence by running run.sh

Cc: shuah@kernel.org Cc: linux-kselftest@vger.kernel.org Signed-off-by: Antonio Quartulli antonio@openvpn.net --- MAINTAINERS | 1 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/net/ovpn/.gitignore | 2 + tools/testing/selftests/net/ovpn/Makefile | 18 + tools/testing/selftests/net/ovpn/config | 8 + tools/testing/selftests/net/ovpn/data-test-tcp.sh | 9 + tools/testing/selftests/net/ovpn/data-test.sh | 153 ++ tools/testing/selftests/net/ovpn/data64.key | 5 + tools/testing/selftests/net/ovpn/float-test.sh | 118 ++ tools/testing/selftests/net/ovpn/ovpn-cli.c | 1822 +++++++++++++++++++++ tools/testing/selftests/net/ovpn/tcp_peers.txt | 5 + tools/testing/selftests/net/ovpn/udp_peers.txt | 5 + 12 files changed, 2147 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS index f753060d4e2467a786778ddd4f835861a603ce02..ffd997cc6a1f1fbc5bc954b585bc15ef7bf2486a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17457,6 +17457,7 @@ T: git https://github.com/OpenVPN/linux-kernel-ovpn.git F: drivers/net/ovpn/ F: include/uapi/linux/ovpn.h F: Documentation/netlink/spec/ovpn.yaml +F: tools/testing/selftests/net/ovpn/

P54 WIRELESS DRIVER M: Christian Lamparter chunkeey@googlemail.com diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index b38199965f99014f3e2636fe8d705972f2c0d148..3ae2dd6492ca70d5e317c6e5b4e2560b060e3214 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..65e23eb0ba86d31aa365b08a8c3468dc56a0d1a4 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/Makefile @@ -0,0 +1,18 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020-2024 OpenVPN, Inc. +# +CFLAGS = -Wall -I../../../../../usr/include +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) + +ovpn-cli: ovpn-cli.c + $(CC) -o ovpn-cli ovpn-cli.c $(CFLAGS) $(LDFLAGS) + +TEST_PROGS = data-test.sh \ + data-test-tcp.sh \ + float-test.sh +TEST_GEN_FILES = ovpn-cli + +include ../../lib.mk diff --git a/tools/testing/selftests/net/ovpn/config b/tools/testing/selftests/net/ovpn/config new file mode 100644 index 0000000000000000000000000000000000000000..5ff47de23c1297a310f0fe39a1ebad16ad014d2c --- /dev/null +++ b/tools/testing/selftests/net/ovpn/config @@ -0,0 +1,8 @@ +CONFIG_NET=y +CONFIG_INET=y +CONFIG_NET_UDP_TUNNEL=y +CONFIG_DST_CACHE=y +CONFIG_CRYPTO_AES=y +CONFIG_CRYPTO_GCM=y +CONFIG_CRYPTO_CHACHA20POLY1305=y +CONFIG_OVPN=y diff --git a/tools/testing/selftests/net/ovpn/data-test-tcp.sh b/tools/testing/selftests/net/ovpn/data-test-tcp.sh new file mode 100755 index 0000000000000000000000000000000000000000..65f05659b5fd8f05d216f2c22898e7f89a6ea4de --- /dev/null +++ b/tools/testing/selftests/net/ovpn/data-test-tcp.sh @@ -0,0 +1,9 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +PROTO="TCP" + +source data-test.sh diff --git a/tools/testing/selftests/net/ovpn/data-test.sh b/tools/testing/selftests/net/ovpn/data-test.sh new file mode 100755 index 0000000000000000000000000000000000000000..e3401481440165141993767cc94fd6df7a37a52e --- /dev/null +++ b/tools/testing/selftests/net/ovpn/data-test.sh @@ -0,0 +1,153 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020-2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +#set -x +set -e + +UDP_PEERS_FILE=${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} + +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() { + 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 + +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 + +ip netns exec peer0 iperf3 -1 -s & +sleep 1 +ip netns exec peer1 iperf3 -Z -t 3 -c 5.5.5.1 + +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 + +ip netns exec peer0 ${OVPN_CLI} del_peer tun0 1 +ip netns exec peer1 ${OVPN_CLI} del_peer tun1 1 + +echo "Setting timeout to 10s MP:" +# bring ifaces down to prevent traffic being sent +for p in $(seq 0 ${NUM_PEERS}); do + ip -n peer${p} link set tun${p} down +done +# set short timeout +for p in $(seq 2 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} set_peer tun0 ${p} 10 10 || true + ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 0 0 +done +# wait for peers to timeout +sleep 15 + +echo "Setting timeout to 10s P2P:" +for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 10 10 +done +sleep 15 + +cleanup diff --git a/tools/testing/selftests/net/ovpn/data64.key b/tools/testing/selftests/net/ovpn/data64.key new file mode 100644 index 0000000000000000000000000000000000000000..a99e88c4e290f58b12f399b857b873f308d9ba09 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/data64.key @@ -0,0 +1,5 @@ +jRqMACN7d7/aFQNT8S7jkrBD8uwrgHbG5OQZP2eu4R1Y7tfpS2bf5RHv06Vi163CGoaIiTX99R3B +ia9ycAH8Wz1+9PWv51dnBLur9jbShlgZ2QHLtUc4a/gfT7zZwULXuuxdLnvR21DDeMBaTbkgbai9 +uvAa7ne1liIgGFzbv+Bas4HDVrygxIxuAnP5Qgc3648IJkZ0QEXPF+O9f0n5+QIvGCxkAUVx+5K6 +KIs+SoeWXnAopELmoGSjUpFtJbagXK82HfdqpuUxT2Tnuef0/14SzVE/vNleBNu2ZbyrSAaah8tE +BofkPJUBFY+YQcfZNM5Dgrw3i+Bpmpq/gpdg5w== diff --git a/tools/testing/selftests/net/ovpn/float-test.sh b/tools/testing/selftests/net/ovpn/float-test.sh new file mode 100755 index 0000000000000000000000000000000000000000..f370dbe8d40bcd40407a795829289c139cd3740a --- /dev/null +++ b/tools/testing/selftests/net/ovpn/float-test.sh @@ -0,0 +1,118 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020-2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +#set -x +set -e + +UDP_PEERS_FILE=${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} + +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 \ + 5.5.5.1 data64.key + fi + fi +} + +cleanup() { + 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 + +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 +# 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 + +cleanup 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..9736e78a92e580ec64db9a96fd45b27c1d457e1c --- /dev/null +++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c @@ -0,0 +1,1822 @@ +// 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 <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> + +/* we use strscpy to make checkpatch happy */ +#define strscpy strncpy + +/* 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; +}; + +struct ovpn_ctx { + __u8 key_enc[KEY_LEN]; + __u8 key_dec[KEY_LEN]; + __u8 nonce[NONCE_LEN]; + + enum ovpn_cipher_alg cipher; + + sa_family_t sa_family; + + __u32 peer_id; + __u16 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; +}; + +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 *)((unsigned char *)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_read_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; + } + + 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_read_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_read_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; + 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; + } + + memset((char *)&local_sock, 0, sizeof(local_sock)); + + 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) +{ + 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_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_PRIMARY); + 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_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; +} + +static int ovpn_handle_iface(struct nl_msg *msg, void *arg) +{ + 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_IFNAME]) { + fprintf(stderr, "no ifname in netlink message\n"); + return NL_SKIP; + } + + fprintf(stderr, "Created ifname: %s\n", + (char *)nla_data(attrs[OVPN_A_IFNAME])); + + return NL_SKIP; +} + +static int ovpn_new_iface(struct ovpn_ctx *ovpn) +{ + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_DEV_NEW); + if (!ctx) + return -ENOMEM; + + NLA_PUT(ctx->nl_msg, OVPN_A_IFNAME, strlen(ovpn->ifname) + 1, + ovpn->ifname); + + if (ovpn->mode_set) + NLA_PUT_U32(ctx->nl_msg, OVPN_A_MODE, ovpn->mode); + + fprintf(stdout, "Creating interface %s with mode %u\n", ovpn->ifname, + ovpn->mode); + + ret = ovpn_nl_msg_send(ctx, ovpn_handle_iface); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_del_iface(struct ovpn_ctx *ovpn) +{ + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_DEV_DEL); + if (!ctx) + return -ENOMEM; + + ret = ovpn_nl_msg_send(ctx, NULL); + nl_ctx_free(ctx); + return ret; +} + +static int nl_seq_check(struct nl_msg *msg, void *arg) +{ + 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, struct nlmsgerr *err, + void *arg) +{ + int *ret = arg; + + *ret = err->error; + return NL_STOP; +} + +static int mcast_ack_handler(struct nl_msg *msg, 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]; + __u32 ifindex; + + fprintf(stderr, "received message from ovpn-dco\n"); + + 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; + } + + 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 void 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 = 0; + 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 != -EINTR) + ret = nl_recvmsgs(sock, cb); + + nl_cb_put(cb); +err_free: + nl_socket_free(sock); +} + +static void usage(const char *cmd) +{ + fprintf(stderr, "Error: invalid arguments.\n\n"); + fprintf(stderr, + "Usage %s <iface> <connect|listen|new_peer|new_multi_peer|set_peer|del_peer|new_key|del_key|recv|send|listen_mcast> [arguments..]\n", + cmd); + fprintf(stderr, "\tiface: tun interface name\n\n"); + + fprintf(stderr, + "* connect <peer_id> <raddr> <rport> <key file>: start connecting peer of TCP-based VPN session\n"); + fprintf(stderr, "\tpeer-id: peer ID of the connecting peer\n"); + fprintf(stderr, "\tremote-addr: peer IP address\n"); + fprintf(stderr, "\tremote-port: peer TCP port\n"); + + fprintf(stderr, + "* listen <lport> <peers_file>: listen for incoming peer TCP connections\n"); + fprintf(stderr, "\tlport: src TCP port\n"); + fprintf(stderr, + "\tpeers_file: file containing one peer per line: Line format:\n"); + fprintf(stderr, "\t\t<peer_id> <vpnaddr>\n\n"); + + fprintf(stderr, + "* new_peer <lport> <peer-id> <raddr> <rport> [vpnaddr]: add new peer\n"); + fprintf(stderr, + "\tpeer-id: peer ID to be used in data packets to/from this peer\n"); + fprintf(stderr, "\tlocal-port: local UDP port\n"); + fprintf(stderr, "\tremote-addr: peer IP address\n"); + fprintf(stderr, "\tremote-port: peer UDP port\n"); + fprintf(stderr, "\tvpnaddr: peer VPN IP\n\n"); + + fprintf(stderr, + "* new_multi_peer <lport> <file>: add multiple peers as listed in the file\n"); + fprintf(stderr, "\tlport: local UDP port to bind to\n"); + fprintf(stderr, + "\tfile: text file containing one peer per line. Line format:\n"); + fprintf(stderr, "\t\t<peer-id> <raddr> <rport> <vpnaddr>\n\n"); + + fprintf(stderr, + "* set_peer <peer-id> <keepalive_interval> <keepalive_timeout>: set peer attributes\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\n"); + + fprintf(stderr, "* del_peer <peer-id>: delete peer\n"); + fprintf(stderr, "\tpeer-id: peer ID of the peer to delete\n\n"); + + fprintf(stderr, + "* new_key <peer-id> <slot> <key_id> <cipher> <key_dir> <key_file>: set data channel key\n"); + fprintf(stderr, + "\tpeer-id: peer ID of the peer to configure the key for\n"); + fprintf(stderr, + "\tcipher: cipher to use, supported: aes (AES-GCM), chachapoly (CHACHA20POLY1305), none\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\n"); + + fprintf(stderr, + "* del_key <peer-id>: erase existing data channel key\n"); + fprintf(stderr, "\tpeer-id: peer ID of the peer to modify\n\n"); + + fprintf(stderr, + "* swap_keys <peer-id>: swap primary and seconday key slots\n"); + fprintf(stderr, "\tpeer-id: peer ID of the peer to modify\n\n"); + + fprintf(stderr, + "* listen_mcast: listen to ovpn-dco 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) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + return ovpn_parse_remote(ovpn, raddr, rport, vpnip); +} + +static void 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); +} + +static void 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; + } + + 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"); + */ +} + +static int ovpn_parse_set_peer(struct ovpn_ctx *ovpn, int argc, char *argv[]) +{ + if (argc < 5) { + usage(argv[0]); + return -1; + } + + ovpn->keepalive_interval = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "keepalive interval value out of range\n"); + return -1; + } + + ovpn->keepalive_timeout = strtoul(argv[4], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "keepalive interval value out of range\n"); + return -1; + } + + return 0; +} + +int main(int argc, char *argv[]) +{ + struct ovpn_ctx ovpn; +// struct nl_ctx *ctx; + int ret; + + if (argc < 2) { + usage(argv[0]); + return -1; + } + + memset(&ovpn, 0, sizeof(ovpn)); + ovpn.sa_family = AF_INET; + ovpn.cli_socket = -1; + + if (argc > 2) { + strscpy(ovpn.ifname, argv[2], IFNAMSIZ - 1); + ovpn.ifname[IFNAMSIZ - 1] = '\0'; + } + + /* all commands except new_iface expect a valid ifindex */ + if (strcmp(argv[1], "new_iface")) { + /* in this case a ifname MUST be defined */ + if (argc < 3) { + usage(argv[0]); + return -1; + } + + ovpn.ifindex = if_nametoindex(ovpn.ifname); + if (!ovpn.ifindex) { + fprintf(stderr, "cannot find interface: %s\n", + strerror(errno)); + return -1; + } + } + + if (!strcmp(argv[1], "new_iface")) { + if (argc > 3) { + 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; + } + + ret = ovpn_new_iface(&ovpn); + if (ret < 0) { + fprintf(stderr, "Cannot create interface %s: %d\n", + ovpn.ifname, ret); + return -1; + } + } else if (!strcmp(argv[1], "del_iface")) { + ret = ovpn_del_iface(&ovpn); + if (ret < 0) { + fprintf(stderr, "Cannot delete interface %s: %d\n", + ovpn.ifname, ret); + return -1; + } + } else if (!strcmp(argv[1], "listen")) { + char peer_id[10], vpnip[100]; + int n; + FILE *fp; + + if (argc < 4) { + usage(argv[0]); + return -1; + } + + ovpn.lport = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn.lport > 65535) { + fprintf(stderr, "lport value out of range\n"); + return -1; + } + + if (argc > 4 && !strcmp(argv[4], "ipv6")) + ovpn.sa_family = AF_INET6; + + ret = ovpn_listen(&ovpn, ovpn.sa_family); + if (ret < 0) { + fprintf(stderr, "cannot listen on TCP socket\n"); + return ret; + } + + fp = fopen(argv[4], "r"); + if (!fp) { + fprintf(stderr, "cannot open file: %s\n", argv[4]); + 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) + ovpn_recv_tcp_data(ovpn.cli_socket); + } else if (!strcmp(argv[1], "connect")) { + if (argc < 5) { + usage(argv[0]); + return -1; + } + + 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 ret; + } + + 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 (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_read_key(argv[6], &ovpn); + if (ret) + return ret; + + ret = ovpn_new_key(&ovpn); + if (ret < 0) { + fprintf(stderr, "cannot set key\n"); + return ret; + } + + ovpn_send_tcp_data(ovpn.socket); + } + } else if (!strcmp(argv[1], "new_peer")) { + if (argc < 7) { + usage(argv[0]); + return -1; + } + + ovpn.lport = strtoul(argv[3], 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[4], argv[5], argv[6], + vpnip); + if (ret < 0) + return ret; + + ret = ovpn_udp_socket(&ovpn, AF_INET6); //ovpn.sa_family ? + if (ret < 0) + return ret; + + ret = ovpn_new_peer(&ovpn, false); + if (ret < 0) { + fprintf(stderr, "cannot add peer to VPN\n"); + return ret; + } + } else if (!strcmp(argv[1], "new_multi_peer")) { + char peer_id[10], raddr[128], rport[10], vpnip[100]; + FILE *fp; + int n; + + if (argc < 5) { + usage(argv[0]); + return -1; + } + + ovpn.lport = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn.lport > 65535) { + fprintf(stderr, "lport value out of range\n"); + return -1; + } + + fp = fopen(argv[4], "r"); + if (!fp) { + fprintf(stderr, "cannot open file: %s\n", argv[4]); + return -1; + } + + ret = ovpn_udp_socket(&ovpn, AF_INET6); + if (ret < 0) + return ret; + + 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; + } + } + } else if (!strcmp(argv[1], "set_peer")) { + ovpn.peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + argv++; + argc--; + + ret = ovpn_parse_set_peer(&ovpn, argc, argv); + if (ret < 0) + return ret; + + ret = ovpn_set_peer(&ovpn); + if (ret < 0) { + fprintf(stderr, "cannot set peer to VPN\n"); + return ret; + } + } else if (!strcmp(argv[1], "del_peer")) { + if (argc < 4) { + usage(argv[0]); + return -1; + } + + ovpn.peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ret = ovpn_del_peer(&ovpn); + if (ret < 0) { + fprintf(stderr, "cannot delete peer to VPN\n"); + return ret; + } + } else if (!strcmp(argv[1], "get_peer")) { + ovpn.peer_id = PEER_ID_UNDEF; + if (argc > 3) + ovpn.peer_id = strtoul(argv[3], NULL, 10); + + fprintf(stderr, "List of peers connected to: %s\n", + ovpn.ifname); + + ret = ovpn_get_peer(&ovpn); + if (ret < 0) { + fprintf(stderr, "cannot get peer(s): %d\n", ret); + return ret; + } + } else if (!strcmp(argv[1], "new_key")) { + if (argc < 8) { + usage(argv[0]); + return -1; + } + + ovpn.peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + int slot = strtoul(argv[4], NULL, 10); + + if (errno == ERANGE || slot < 1 || slot > 2) { + fprintf(stderr, "ket 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; + } + + ovpn.key_id = strtoul(argv[5], NULL, 10); + if (errno == ERANGE || ovpn.key_id > 2) { + fprintf(stderr, "ket ID out of range\n"); + return -1; + } + + ret = ovpn_read_cipher(argv[6], &ovpn); + if (ret < 0) + return ret; + + ret = ovpn_read_key_direction(argv[7], &ovpn); + if (ret < 0) + return ret; + + ret = ovpn_read_key(argv[8], &ovpn); + if (ret) + return ret; + + ret = ovpn_new_key(&ovpn); + if (ret < 0) { + fprintf(stderr, "cannot set key\n"); + return ret; + } + } else if (!strcmp(argv[1], "del_key")) { + if (argc < 3) { + usage(argv[0]); + return -1; + } + + ovpn.peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + argv++; + argc--; + + ret = ovpn_del_key(&ovpn); + if (ret < 0) { + fprintf(stderr, "cannot delete key\n"); + return ret; + } + } else if (!strcmp(argv[1], "swap_keys")) { + if (argc < 3) { + usage(argv[0]); + return -1; + } + + ovpn.peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + argv++; + argc--; + + ret = ovpn_swap_keys(&ovpn); + if (ret < 0) { + fprintf(stderr, "cannot swap keys\n"); + return ret; + } + } else if (!strcmp(argv[1], "listen_mcast")) { + ovpn_listen_mcast(); + } else { + usage(argv[0]); + return -1; + } + + 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/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