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 are 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 | 7 +++ drivers/net/Makefile | 1 + drivers/net/ovpn/Makefile | 10 +++++ drivers/net/ovpn/main.c | 112 ++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 138 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS index 0456a33ef65792bacb5d305a6384d245844fb743..6de1767f7cc80a571e0ab6e9f4dfe5650eb704d4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17472,6 +17472,14 @@ F: arch/openrisc/ F: drivers/irqchip/irq-ompic.c F: drivers/irqchip/irq-or1k-*

+OPENVPN DATA CHANNEL OFFLOAD +M: Antonio Quartulli antonio@openvpn.net +L: openvpn-devel@lists.sourceforge.net (subscribers-only) +L: netdev@vger.kernel.org +S: Supported +T: git https://github.com/OpenVPN/linux-kernel-ovpn.git +F: drivers/net/ovpn/ + OPENVSWITCH M: Pravin B Shelar pshelar@ovn.org L: netdev@vger.kernel.org diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 1fd5acdc73c6af0e1a861867039c3624fc618e25..a7c5c166f9ced748d73843f81efb802072e15434 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -115,6 +115,13 @@ config WIREGUARD_DEBUG

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

+config OVPN + tristate "OpenVPN data channel offload" + depends on NET && INET + 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..ae19cf445b29367da680e226f06a341c42c892c2 --- /dev/null +++ b/drivers/net/ovpn/Makefile @@ -0,0 +1,10 @@ +# 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 diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c new file mode 100644 index 0000000000000000000000000000000000000000..72c56e73771cdece22e50645b29c79962f06caf3 --- /dev/null +++ b/drivers/net/ovpn/main.c @@ -0,0 +1,112 @@ +// 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 <net/rtnetlink.h> + +static const struct net_device_ops ovpn_netdev_ops = { +}; + +/** + * 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' + */ +static bool ovpn_dev_is_valid(const struct net_device *dev) +{ + return dev->netdev_ops == &ovpn_netdev_ops; +} + +static int ovpn_newlink(struct net *src_net, struct net_device *dev, + struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + return -EOPNOTSUPP; +} + +static struct rtnl_link_ops ovpn_link_ops = { + .kind = "ovpn", + .netns_refund = false, + .newlink = ovpn_newlink, + .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("OpenVPN data channel offload (ovpn)"); +MODULE_AUTHOR("(C) 2020-2024 OpenVPN, Inc."); +MODULE_LICENSE("GPL");

Add basic infrastructure for handling ovpn interfaces.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/Makefile | 1 + drivers/net/ovpn/io.c | 22 +++++++++ drivers/net/ovpn/io.h | 24 ++++++++++ drivers/net/ovpn/main.c | 102 +++++++++++++++++++++++++++++++++++++++--- drivers/net/ovpn/ovpnstruct.h | 6 +++ drivers/net/ovpn/proto.h | 38 ++++++++++++++++ include/uapi/linux/if_link.h | 15 +++++++ 7 files changed, 203 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index 19305a39e57eede2dc391aa0423702c5321649a6..201dc001419f1d99ae95c0ee0f96e68f8a4eac16 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -8,5 +8,6 @@

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/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..a90537e9af6c0d2f38da229bdc2d8c639f2d11d1 --- /dev/null +++ b/drivers/net/ovpn/io.h @@ -0,0 +1,24 @@ +/* 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_ + +/* DATA_V2 header size with AEAD encryption */ +#define OVPN_HEAD_ROOM (OVPN_OPCODE_SIZE + OVPN_NONCE_WIRE_SIZE + \ + 16 /* AEAD TAG length */ + \ + max(sizeof(struct udphdr), sizeof(struct tcphdr)) +\ + max(sizeof(struct ipv6hdr), sizeof(struct iphdr))) + +/* max padding required by encryption */ +#define OVPN_MAX_PADDING 16 + +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 index 3475dab4b40f3edd882e05dbdf8badd03d7c78a3..60954c5b2b9254db1d24d01ac383935765c7ce5b 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -10,14 +10,42 @@ #include <linux/genetlink.h> #include <linux/module.h> #include <linux/netdevice.h> +#include <linux/inetdevice.h> +#include <net/ip.h> #include <net/rtnetlink.h> -#include <uapi/linux/ovpn.h> +#include <uapi/linux/if_arp.h>

#include "ovpnstruct.h" #include "main.h" #include "netlink.h" +#include "io.h" +#include "proto.h" + +static int ovpn_net_open(struct net_device *dev) +{ + netif_tx_start_all_queues(dev); + return 0; +} + +static int ovpn_net_stop(struct net_device *dev) +{ + netif_tx_stop_all_queues(dev); + return 0; +}

static const struct net_device_ops ovpn_netdev_ops = { + .ndo_open = ovpn_net_open, + .ndo_stop = ovpn_net_stop, + .ndo_start_xmit = ovpn_net_xmit, +}; + +static const struct device_type ovpn_type = { + .name = OVPN_FAMILY_NAME, +}; + +static const struct nla_policy ovpn_policy[IFLA_OVPN_MAX + 1] = { + [IFLA_OVPN_MODE] = NLA_POLICY_RANGE(NLA_U8, OVPN_MODE_P2P, + OVPN_MODE_MP), };

/** @@ -31,16 +59,69 @@ bool ovpn_dev_is_valid(const struct net_device *dev) return dev->netdev_ops == &ovpn_netdev_ops; }

+static void ovpn_setup(struct net_device *dev) +{ + netdev_features_t feat = NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM | + NETIF_F_GSO | NETIF_F_GSO_SOFTWARE | + NETIF_F_HIGHDMA; + + dev->needs_free_netdev = true; + + dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS; + + dev->netdev_ops = &ovpn_netdev_ops; + + dev->hard_header_len = 0; + dev->addr_len = 0; + dev->mtu = ETH_DATA_LEN - OVPN_HEAD_ROOM; + dev->min_mtu = IPV4_MIN_MTU; + dev->max_mtu = IP_MAX_MTU - OVPN_HEAD_ROOM; + + dev->type = ARPHRD_NONE; + dev->flags = IFF_POINTOPOINT | IFF_NOARP; + dev->priv_flags |= IFF_NO_QUEUE; + + dev->lltx = true; + dev->features |= feat; + dev->hw_features |= feat; + dev->hw_enc_features |= feat; + + dev->needed_headroom = ALIGN(OVPN_HEAD_ROOM, 4); + dev->needed_tailroom = OVPN_MAX_PADDING; + + SET_NETDEV_DEVTYPE(dev, &ovpn_type); +} + static int ovpn_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { - return -EOPNOTSUPP; + struct ovpn_priv *ovpn = netdev_priv(dev); + enum ovpn_mode mode = OVPN_MODE_P2P; + + if (data && data[IFLA_OVPN_MODE]) { + mode = nla_get_u8(data[IFLA_OVPN_MODE]); + netdev_dbg(dev, "setting device mode: %u\n", mode); + } + + ovpn->dev = dev; + ovpn->mode = mode; + + /* turn carrier explicitly off after registration, this way state is + * clearly defined + */ + netif_carrier_off(dev); + + return register_netdevice(dev); }

static struct rtnl_link_ops ovpn_link_ops = { .kind = "ovpn", .netns_refund = false, + .priv_size = sizeof(struct ovpn_priv), + .setup = ovpn_setup, + .policy = ovpn_policy, + .maxtype = IFLA_OVPN_MAX, .newlink = ovpn_newlink, .dellink = unregister_netdevice_queue, }; @@ -49,26 +130,37 @@ 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); + struct ovpn_priv *ovpn;

if (!ovpn_dev_is_valid(dev)) return NOTIFY_DONE;

+ ovpn = netdev_priv(dev); + switch (state) { case NETDEV_REGISTER: - /* add device to internal list for later destruction upon - * unregistration - */ + ovpn->registered = true; break; case NETDEV_UNREGISTER: + /* twiddle thumbs on netns device moves */ + if (dev->reg_state != NETREG_UNREGISTERING) + break; + /* can be delivered multiple times, so check registered flag, * then destroy the interface */ + if (!ovpn->registered) + return NOTIFY_DONE; + + netif_carrier_off(dev); + ovpn->registered = false; break; case NETDEV_POST_INIT: case NETDEV_GOING_DOWN: case NETDEV_DOWN: case NETDEV_UP: case NETDEV_PRE_UP: + break; default: return NOTIFY_DONE; } diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h index b4e37e922fe5a5659e030174f1e42b3935967ca0..312bc22199383fed0746335fde3339646bb68b2b 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -11,15 +11,21 @@ #define _NET_OVPN_OVPNSTRUCT_H_

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

/** * struct ovpn_priv - 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, ..) */ struct ovpn_priv { struct net_device *dev; netdevice_tracker dev_tracker; + bool registered; + enum ovpn_mode mode; };

#endif /* _NET_OVPN_OVPNSTRUCT_H_ */ diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h new file mode 100644 index 0000000000000000000000000000000000000000..00bb3725ac7ab7040c97eb012c2639b2d6967de1 --- /dev/null +++ b/drivers/net/ovpn/proto.h @@ -0,0 +1,38 @@ +/* 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_PROTO_H_ +#define _NET_OVPN_PROTO_H_ + +/* When the OpenVPN protocol is ran in AEAD mode, use + * the OpenVPN packet ID as the AEAD nonce: + * + * 00000005 521c3b01 4308c041 + * [seq # ] [ nonce_tail ] + * [ 12-byte full IV ] -> OVPN_NONCE_SIZE + * [4-bytes -> OVPN_NONCE_WIRE_SIZE + * on wire] + */ + +/* nonce size (96bits) as required by AEAD ciphers */ +#define OVPN_NONCE_SIZE 12 +/* last 8 bytes of AEAD nonce: provided by userspace and usually derived + * from key material generated during TLS handshake + */ +#define OVPN_NONCE_TAIL_SIZE 8 + +/* OpenVPN nonce size reduced by 8-byte nonce tail -- this is the + * size of the AEAD Associated Data (AD) sent over the wire + * and is normally the head of the IV + */ +#define OVPN_NONCE_WIRE_SIZE (OVPN_NONCE_SIZE - OVPN_NONCE_TAIL_SIZE) + +#define OVPN_OPCODE_SIZE 4 /* DATA_V2 opcode size */ + +#endif /* _NET_OVPN_PROTO_H_ */ diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 2575e0cd9b482e78984ca6528dd7d4a24f03e290..9914f8963060ba6db56fc379c3016458002bc93f 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -1976,4 +1976,19 @@ enum {

#define IFLA_DSA_MAX (__IFLA_DSA_MAX - 1)

+/* OVPN section */ + +enum ovpn_mode { + OVPN_MODE_P2P, + OVPN_MODE_MP, +}; + +enum { + IFLA_OVPN_UNSPEC, + IFLA_OVPN_MODE, + __IFLA_OVPN_MAX, +}; + +#define IFLA_OVPN_MAX (__IFLA_OVPN_MAX - 1) + #endif /* _UAPI_LINUX_IF_LINK_H */

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/Kconfig | 1 + drivers/net/ovpn/Makefile | 2 + drivers/net/ovpn/bind.c | 58 +++++++ drivers/net/ovpn/bind.h | 101 +++++++++++ drivers/net/ovpn/main.c | 18 +- drivers/net/ovpn/ovpnstruct.h | 4 + drivers/net/ovpn/peer.c | 385 ++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/peer.h | 78 +++++++++ 8 files changed, 646 insertions(+), 1 deletion(-)

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index a7c5c166f9ced748d73843f81efb802072e15434..d6c1810f042e222143f53563a8d8df4bc9df27ed 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -118,6 +118,7 @@ config WIREGUARD_DEBUG config OVPN tristate "OpenVPN data channel offload" depends on NET && INET + select DST_CACHE help This module enhances the performance of the OpenVPN userspace software by offloading the data channel processing to kernelspace. diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index 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..343e6055deef9223a11176f62b94f6c8ed3eb18f --- /dev/null +++ b/drivers/net/ovpn/bind.h @@ -0,0 +1,101 @@ +/* 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; +}; + +/** + * 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 union ovpn_sockaddr *remote; + + if (unlikely(!bind)) + return false; + + remote = &bind->remote; + + switch (skb->protocol) { + case htons(ETH_P_IP): + if (unlikely(remote->in4.sin_family != AF_INET)) + return false; + + 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 htons(ETH_P_IPV6): + if (unlikely(remote->in6.sin6_family != AF_INET6)) + return false; + + 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 274d6166741ef2d6275a252d0c042bc66f8f41f7..c37cb47495f04bb7a6facdf30e5877ddef0ddb29 100644 --- a/drivers/net/ovpn/main.c +++ b/drivers/net/ovpn/main.c @@ -19,8 +19,14 @@ #include "main.h" #include "netlink.h" #include "io.h" +#include "peer.h" #include "proto.h"

+static int ovpn_net_init(struct net_device *dev) +{ + return 0; +} + static int ovpn_net_open(struct net_device *dev) { struct ovpn_priv *ovpn = netdev_priv(dev); @@ -43,6 +49,7 @@ 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, @@ -115,6 +122,7 @@ static int ovpn_newlink(struct net *src_net, struct net_device *dev,

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

/* turn carrier explicitly off after registration, this way state is * clearly defined @@ -163,10 +171,18 @@ static int ovpn_netdev_notifier_call(struct notifier_block *nb,

netif_carrier_off(dev); ovpn->registered = false; + + if (ovpn->mode == OVPN_MODE_P2P) + ovpn_peer_release_p2p(ovpn, + OVPN_DEL_PEER_REASON_TEARDOWN); + break; + case NETDEV_DOWN: + if (ovpn->mode == OVPN_MODE_P2P) + ovpn_peer_release_p2p(ovpn, + OVPN_DEL_PEER_REASON_ADMINDOWN); break; case NETDEV_POST_INIT: case NETDEV_GOING_DOWN: - case NETDEV_DOWN: case NETDEV_UP: case NETDEV_PRE_UP: break; diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h index 312bc22199383fed0746335fde3339646bb68b2b..a6cfb436f3d0d79a0c438e647f8652021119b0ed 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -20,12 +20,16 @@ * @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 */ struct ovpn_priv { struct net_device *dev; netdevice_tracker dev_tracker; bool registered; enum ovpn_mode mode; + spinlock_t lock; /* protect writing to the ovpn_priv object */ + struct ovpn_peer __rcu *peer; };

#endif /* _NET_OVPN_OVPNSTRUCT_H_ */ diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c new file mode 100644 index 0000000000000000000000000000000000000000..427276dd910f4658dd0bfb272b13631976df622d --- /dev/null +++ b/drivers/net/ovpn/peer.c @@ -0,0 +1,385 @@ +// 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 "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_priv *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->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, + "cannot initialize dst cache for peer %u\n", + peer->id); + kfree(peer); + return ERR_PTR(ret); + } + + netdev_hold(ovpn->dev, &ovpn->dev_tracker, GFP_KERNEL); + + return peer; +} + +/** + * ovpn_peer_release_rcu - RCU callback performing last peer release steps + * @head: RCU member of the ovpn_peer + */ +static void ovpn_peer_release_rcu(struct rcu_head *head) +{ + struct ovpn_peer *peer = container_of(head, struct ovpn_peer, rcu); + + /* this call will immediately free the dst_cache, therefore we + * perform it in the RCU callback, when all contexts are done + */ + dst_cache_destroy(&peer->dst_cache); + kfree(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); + netdev_put(peer->ovpn->dev, &peer->ovpn->dev_tracker); + call_rcu(&peer->rcu, ovpn_peer_release_rcu); +} + +/** + * 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); +} + +/** + * ovpn_peer_skb_to_sockaddr - fill sockaddr with skb source address + * @skb: the packet to extract data from + * @ss: the sockaddr to fill + * + * Return: sockaddr length on success or -1 otherwise + */ +static int ovpn_peer_skb_to_sockaddr(struct sk_buff *skb, + struct sockaddr_storage *ss) +{ + struct sockaddr_in6 *sa6; + struct sockaddr_in *sa4; + + switch (skb->protocol) { + case htons(ETH_P_IP): + 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; + return sizeof(*sa4); + case htons(ETH_P_IPV6): + sa6 = (struct sockaddr_in6 *)ss; + sa6->sin6_family = AF_INET6; + sa6->sin6_addr = ipv6_hdr(skb)->saddr; + sa6->sin6_port = udp_hdr(skb)->source; + return sizeof(*sa6); + } + + return -1; +} + +/** + * 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_priv *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_priv *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_priv *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_priv *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_priv *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); + /* in P2P mode the carrier is switched on when the peer is added */ + netif_carrier_on(ovpn->dev); + 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_priv *ovpn, struct ovpn_peer *peer) +{ + switch (ovpn->mode) { + case OVPN_MODE_P2P: + return ovpn_peer_add_p2p(ovpn, peer); + default: + return -EOPNOTSUPP; + } +} + +static void ovpn_peer_remove(struct ovpn_peer *peer, + enum ovpn_del_peer_reason reason) +{ + switch (peer->ovpn->mode) { + case OVPN_MODE_P2P: + RCU_INIT_POINTER(peer->ovpn->peer, NULL); + /* in P2P mode the carrier is switched off when the peer is + * deleted so that third party protocols can react accordingly + */ + netif_carrier_off(peer->ovpn->dev); + break; + default: + return; + } + + peer->delete_reason = reason; + + /* reference from ovpn->peer or hashtable dropped */ + ovpn_peer_put(peer); +} + +/** + * 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) +{ + struct ovpn_peer *tmp; + + lockdep_assert_held(&peer->ovpn->lock); + + tmp = rcu_dereference_protected(peer->ovpn->peer, + lockdep_is_held(&peer->ovpn->lock)); + if (tmp != peer) { + DEBUG_NET_WARN_ON_ONCE(1); + return -ENOENT; + } + + ovpn_peer_remove(peer, reason); + + return 0; +} + +/** + * ovpn_peer_release_p2p - release peer upon P2P device teardown + * @ovpn: the instance being torn down + * @reason: the reason for releasing the peer + */ +void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, + enum ovpn_del_peer_reason reason) +{ + 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, reason); + 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..c3458732b2cfcd439644423ec8cd77595f9ed5f3 --- /dev/null +++ b/drivers/net/ovpn/peer.h @@ -0,0 +1,78 @@ +/* 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 <net/dst_cache.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 + * @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_priv *ovpn; + u32 id; + struct { + struct in_addr ipv4; + struct in6_addr ipv6; + } vpn_addrs; + struct dst_cache dst_cache; + struct ovpn_bind __rcu *bind; + 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_priv *ovpn, u32 id); +int ovpn_peer_add(struct ovpn_priv *ovpn, struct ovpn_peer *peer); +int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason); +void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, + enum ovpn_del_peer_reason reason); + +struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn, + struct sk_buff *skb); +struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id); + +#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/Kconfig | 1 + drivers/net/ovpn/io.c | 129 +++++++++++++++++++++++++- drivers/net/ovpn/peer.c | 35 ++++++++ drivers/net/ovpn/peer.h | 4 + drivers/net/ovpn/skb.h | 54 +++++++++++ drivers/net/ovpn/udp.c | 234 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/udp.h | 5 ++ 7 files changed, 461 insertions(+), 1 deletion(-)

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

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

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

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

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

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

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

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

#endif /* _NET_OVPN_OVPNPEER_H_ */ diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h new file mode 100644 index 0000000000000000000000000000000000000000..392bb3f77262efa580231d2eada2aa2f399a71f8 --- /dev/null +++ b/drivers/net/ovpn/skb.h @@ -0,0 +1,54 @@ +/* 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) { + if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr))) + return 0; + proto = htons(ETH_P_IPV6); + } + + return proto; +} + +#endif /* _NET_OVPN_SKB_H_ */ diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c index c00e07f148d72ff737e732028fd73f82a507fb57..c0e7aa289ad3345fcd91e7c890f70961300c356f 100644 --- a/drivers/net/ovpn/udp.c +++ b/drivers/net/ovpn/udp.c @@ -7,15 +7,249 @@ */

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

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

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

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

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

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

Packets received over the socket are forwarded to the user device.

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

Note: no decryption/decapsulation exists yet, packets are forwarded as they arrive without much processing.

Signed-off-by: Antonio Quartulli antonio@openvpn.net --- drivers/net/ovpn/io.c | 64 +++++++++++++++++++++++++++++- drivers/net/ovpn/io.h | 2 + drivers/net/ovpn/main.c | 13 +++++- drivers/net/ovpn/ovpnstruct.h | 3 ++ drivers/net/ovpn/proto.h | 50 ++++++++++++++++++++++- drivers/net/ovpn/socket.c | 24 +++++++++++ drivers/net/ovpn/udp.c | 92 ++++++++++++++++++++++++++++++++++++++++++- drivers/net/ovpn/udp.h | 3 +- 8 files changed, 246 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 2a3dbc723813a14070159318097755cc7ea3f216..9f5c6b06c79681048f750fce89e9683da41ea642 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -9,15 +9,77 @@

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

-#include "io.h" #include "ovpnstruct.h" #include "peer.h" +#include "io.h" +#include "netlink.h" +#include "proto.h" #include "udp.h" #include "skb.h" #include "socket.h"

+/* Called after decrypt to write the IP packet to the device. + * This method is expected to manage/free the skb. + */ +static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb) +{ + unsigned int pkt_len; + int ret; + + /* we can't guarantee the packet wasn't corrupted before entering the + * VPN, therefore we give other layers a chance to check that + */ + skb->ip_summed = CHECKSUM_NONE; + + /* skb hash for transport packet no longer valid after decapsulation */ + skb_clear_hash(skb); + + /* post-decrypt scrub -- prepare to inject encapsulated packet onto the + * interface, based on __skb_tunnel_rx() in dst.h + */ + skb->dev = peer->ovpn->dev; + skb_set_queue_mapping(skb, 0); + skb_scrub_packet(skb, true); + + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + skb_reset_inner_headers(skb); + + /* cause packet to be "received" by the interface */ + pkt_len = skb->len; + ret = gro_cells_receive(&peer->ovpn->gro_cells, skb); + if (likely(ret == NET_RX_SUCCESS)) + /* update RX stats with the size of decrypted packet */ + dev_sw_netstats_rx_add(peer->ovpn->dev, pkt_len); +} + +static void ovpn_decrypt_post(struct sk_buff *skb, int ret) +{ + struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer; + + if (unlikely(ret < 0)) + 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); + kfree_skb(skb); +} + +/* RX path entry point: decrypt packet and forward it to the device */ +void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb) +{ + ovpn_skb_cb(skb)->peer = peer; + ovpn_decrypt_post(skb, 0); +} + static void ovpn_encrypt_post(struct sk_buff *skb, int ret) { struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer; diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h index a90537e9af6c0d2f38da229bdc2d8c639f2d11d1..b3830b787e16f3bdcaaff94e5bbe89be3e1006fe 100644 --- a/drivers/net/ovpn/io.h +++ b/drivers/net/ovpn/io.h @@ -21,4 +21,6 @@

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); + #endif /* _NET_OVPN_OVPN_H_ */ diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c index c37cb47495f04bb7a6facdf30e5877ddef0ddb29..c27e4c190f5bdf061a71c516344551ef7cd31496 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 <net/gro_cells.h> #include <net/ip.h> #include <net/rtnetlink.h> #include <uapi/linux/if_arp.h> @@ -24,7 +25,16 @@

static int ovpn_net_init(struct net_device *dev) { - return 0; + struct ovpn_priv *ovpn = netdev_priv(dev); + + return gro_cells_init(&ovpn->gro_cells, dev); +} + +static void ovpn_net_uninit(struct net_device *dev) +{ + struct ovpn_priv *ovpn = netdev_priv(dev); + + gro_cells_destroy(&ovpn->gro_cells); }

static int ovpn_net_open(struct net_device *dev) @@ -50,6 +60,7 @@ static int ovpn_net_stop(struct net_device *dev)

static const struct net_device_ops ovpn_netdev_ops = { .ndo_init = ovpn_net_init, + .ndo_uninit = ovpn_net_uninit, .ndo_open = ovpn_net_open, .ndo_stop = ovpn_net_stop, .ndo_start_xmit = ovpn_net_xmit, diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h index a6cfb436f3d0d79a0c438e647f8652021119b0ed..1cca91d869d9e3c722a0933a426255f05daf8097 100644 --- a/drivers/net/ovpn/ovpnstruct.h +++ b/drivers/net/ovpn/ovpnstruct.h @@ -10,6 +10,7 @@ #ifndef _NET_OVPN_OVPNSTRUCT_H_ #define _NET_OVPN_OVPNSTRUCT_H_

+#include <net/gro_cells.h> #include <net/net_trackers.h> #include <uapi/linux/if_link.h> #include <uapi/linux/ovpn.h> @@ -22,6 +23,7 @@ * @mode: device operation mode (i.e. p2p, mp, ..) * @lock: protect this object * @peer: in P2P mode, this is the only remote peer + * @gro_cells: pointer to the Generic Receive Offload cell */ struct ovpn_priv { struct net_device *dev; @@ -30,6 +32,7 @@ struct ovpn_priv { enum ovpn_mode mode; spinlock_t lock; /* protect writing to the ovpn_priv object */ struct ovpn_peer __rcu *peer; + struct gro_cells gro_cells; };

#endif /* _NET_OVPN_OVPNSTRUCT_H_ */ diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h index 00bb3725ac7ab7040c97eb012c2639b2d6967de1..34a812869b2e92e8bab0ebb87d46b67c3bbccf9f 100644 --- a/drivers/net/ovpn/proto.h +++ b/drivers/net/ovpn/proto.h @@ -10,6 +10,11 @@ #ifndef _NET_OVPN_PROTO_H_ #define _NET_OVPN_PROTO_H_

+#include "main.h" + +#include <linux/bitfield.h> +#include <linux/skbuff.h> + /* When the OpenVPN protocol is ran in AEAD mode, use * the OpenVPN packet ID as the AEAD nonce: * @@ -34,5 +39,48 @@ #define OVPN_NONCE_WIRE_SIZE (OVPN_NONCE_SIZE - OVPN_NONCE_TAIL_SIZE)

#define OVPN_OPCODE_SIZE 4 /* DATA_V2 opcode size */ +#define OVPN_OPCODE_KEYID_MASK 0x07000000 +#define OVPN_OPCODE_PKTTYPE_MASK 0xF8000000 +#define OVPN_OPCODE_PEERID_MASK 0x00FFFFFF + +/* packet opcodes of interest to us */ +#define OVPN_DATA_V1 6 /* data channel v1 packet */ +#define OVPN_DATA_V2 9 /* data channel v2 packet */ + +#define OVPN_PEER_ID_UNDEF 0x00FFFFFF + +/** + * ovpn_opcode_from_skb - extract OP code from skb at specified offset + * @skb: the packet to extract the OP code from + * @offset: the offset in the data buffer where the OP code is located + * + * Note: this function assumes that the skb head was pulled enough + * to access the first byte. + * + * Return: the OP code + */ +static inline u8 ovpn_opcode_from_skb(const struct sk_buff *skb, u16 offset) +{ + u32 opcode = be32_to_cpu(*(__be32 *)(skb->data + offset)); + + return FIELD_GET(OVPN_OPCODE_PKTTYPE_MASK, opcode); +} + +/** + * ovpn_peer_id_from_skb - extract peer ID from skb at specified offset + * @skb: the packet to extract the OP code from + * @offset: the offset in the data buffer where the OP code is located + * + * Note: this function assumes that the skb head was pulled enough + * to access the first 4 bytes. + * + * Return: the peer ID + */ +static inline u32 ovpn_peer_id_from_skb(const struct sk_buff *skb, u16 offset) +{ + u32 opcode = be32_to_cpu(*(__be32 *)(skb->data + offset)); + + return FIELD_GET(OVPN_OPCODE_PEERID_MASK, opcode); +}

-#endif /* _NET_OVPN_PROTO_H_ */ +#endif /* _NET_OVPN_OVPNPROTO_H_ */ diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c index 0abac02e13fb4ef1e212dacae075d5b58e872d34..e10590924e3f9fe605309989be84866e2e508944 100644 --- a/drivers/net/ovpn/socket.c +++ b/drivers/net/ovpn/socket.c @@ -23,6 +23,9 @@ static void ovpn_socket_detach(struct socket *sock) if (!sock) return;

+ if (sock->sk->sk_protocol == IPPROTO_UDP) + ovpn_udp_socket_detach(sock); + sockfd_put(sock); }

@@ -70,6 +73,27 @@ static int ovpn_socket_attach(struct socket *sock, struct ovpn_peer *peer) return ret; }

+/* Retrieve the corresponding ovpn object from a UDP socket + * rcu_read_lock must be held on entry + */ +struct ovpn_priv *ovpn_from_udp_sock(struct sock *sk) +{ + struct ovpn_socket *ovpn_sock; + + if (unlikely(READ_ONCE(udp_sk(sk)->encap_type) != UDP_ENCAP_OVPNINUDP)) + return NULL; + + ovpn_sock = rcu_dereference_sk_user_data(sk); + if (unlikely(!ovpn_sock)) + return NULL; + + /* make sure that sk matches our stored transport socket */ + if (unlikely(!ovpn_sock->sock || sk != ovpn_sock->sock->sk)) + return NULL; + + return ovpn_sock->ovpn; +} + /** * ovpn_socket_new - create a new socket and initialize it * @sock: the kernel socket to embed diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c index c0e7aa289ad3345fcd91e7c890f70961300c356f..975392fc39bc4c0107a07a53795afecd88d72c53 100644 --- a/drivers/net/ovpn/udp.c +++ b/drivers/net/ovpn/udp.c @@ -23,9 +23,83 @@ #include "bind.h" #include "io.h" #include "peer.h" +#include "proto.h" #include "socket.h" #include "udp.h"

+/** + * ovpn_udp_encap_recv - Start processing a received UDP packet. + * @sk: socket over which the packet was received + * @skb: the received packet + * + * If the first byte of the payload is DATA_V2, the packet is further processed, + * otherwise it is forwarded to the UDP stack for delivery to user space. + * + * Return: + * 0 if skb was consumed or dropped + * >0 if skb should be passed up to userspace as UDP (packet not consumed) + * <0 if skb should be resubmitted as proto -N (packet not consumed) + */ +static int ovpn_udp_encap_recv(struct sock *sk, struct sk_buff *skb) +{ + struct ovpn_priv *ovpn; + struct ovpn_peer *peer; + u32 peer_id; + u8 opcode; + + ovpn = ovpn_from_udp_sock(sk); + if (unlikely(!ovpn)) { + net_err_ratelimited("%s: cannot obtain ovpn object from UDP socket\n", + netdev_name(ovpn->dev)); + goto drop_noovpn; + } + + /* Make sure the first 4 bytes of the skb data buffer after the UDP + * header are accessible. + * They are required to fetch the OP code, the key ID and the peer ID. + */ + if (unlikely(!pskb_may_pull(skb, sizeof(struct udphdr) + + OVPN_OPCODE_SIZE))) { + net_dbg_ratelimited("%s: packet too small from UDP socket\n", + netdev_name(ovpn->dev)); + goto drop; + } + + opcode = ovpn_opcode_from_skb(skb, sizeof(struct udphdr)); + if (unlikely(opcode != OVPN_DATA_V2)) { + /* DATA_V1 is not supported */ + if (opcode == OVPN_DATA_V1) + goto drop; + + /* unknown or control packet: let it bubble up to userspace */ + return 1; + } + + peer_id = ovpn_peer_id_from_skb(skb, sizeof(struct udphdr)); + /* some OpenVPN server implementations send data packets with the + * peer-id set to UNDEF. In this case we skip the peer lookup by peer-id + * and we try with the transport address + */ + if (peer_id == OVPN_PEER_ID_UNDEF) + peer = ovpn_peer_get_by_transp_addr(ovpn, skb); + else + peer = ovpn_peer_get_by_id(ovpn, peer_id); + + if (unlikely(!peer)) + goto drop; + + /* pop off outer UDP header */ + __skb_pull(skb, sizeof(struct udphdr)); + ovpn_recv(peer, skb); + return 0; + +drop: + dev_core_stats_rx_dropped_inc(ovpn->dev); +drop_noovpn: + kfree_skb(skb); + return 0; +} + /** * ovpn_udp4_output - send IPv4 packet over udp socket * @peer: the destination peer @@ -262,8 +336,12 @@ void ovpn_udp_send_skb(struct ovpn_peer *peer, struct sk_buff *skb) */ int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_priv *ovpn) { + struct udp_tunnel_sock_cfg cfg = { + .encap_type = UDP_ENCAP_OVPNINUDP, + .encap_rcv = ovpn_udp_encap_recv, + }; struct ovpn_socket *old_data; - int ret = 0; + int ret;

/* make sure no pre-existing encapsulation handler exists */ rcu_read_lock(); @@ -271,6 +349,7 @@ int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_priv *ovpn) if (!old_data) { /* socket is currently unused - we can take it */ rcu_read_unlock(); + setup_udp_tunnel_sock(sock_net(sock->sk), sock, &cfg); return 0; }

@@ -297,3 +376,14 @@ int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_priv *ovpn)

return ret; } + +/** + * ovpn_udp_socket_detach - clean udp-tunnel status for this socket + * @sock: the socket to clean + */ +void ovpn_udp_socket_detach(struct socket *sock) +{ + struct udp_tunnel_sock_cfg cfg = { }; + + setup_udp_tunnel_sock(sock_net(sock->sk), sock, &cfg); +} diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h index 44ebeb82325dc4d172da7e29fb36f21a5609ea8d..90a46821d1e999fea0e1aa0f7de9db65decf71d5 100644 --- a/drivers/net/ovpn/udp.h +++ b/drivers/net/ovpn/udp.h @@ -16,7 +16,8 @@ struct ovpn_priv; struct socket;

int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_priv *ovpn); - +void ovpn_udp_socket_detach(struct socket *sock); void ovpn_udp_send_skb(struct ovpn_peer *peer, struct sk_buff *skb); +struct ovpn_priv *ovpn_from_udp_sock(struct sock *sk);

#endif /* _NET_OVPN_UDP_H_ */

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

To be exported via netlink.

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

diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile index ccdaeced1982c851475657860a005ff2b9dfbd13..d43fda72646bdc7644d9a878b56da0a0e5680c98 100644 --- a/drivers/net/ovpn/Makefile +++ b/drivers/net/ovpn/Makefile @@ -17,4 +17,5 @@ ovpn-y += netlink-gen.o ovpn-y += peer.o ovpn-y += pktid.o ovpn-y += socket.o +ovpn-y += stats.o ovpn-y += udp.o diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index a6db02f712203430942e3908480026f4dbac673a..8414dbd24467d77a5122daa9c3c745aa5e258c98 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -12,6 +12,7 @@ #include <linux/skbuff.h> #include <net/gro_cells.h> #include <net/gso.h> +#include <net/ip.h>

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

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

+ ovpn_peer_stats_increment_rx(&peer->link_stats, skb->len); + /* get the key slot matching the key ID in the received packet */ key_id = ovpn_key_id_from_skb(skb); ks = ovpn_crypto_key_id_to_slot(&peer->crypto, key_id); @@ -176,6 +181,7 @@ void ovpn_encrypt_post(void *data, int ret) struct ovpn_crypto_key_slot *ks; struct sk_buff *skb = data; struct ovpn_peer *peer; + unsigned int orig_len;

/* encryption is happening asynchronously. This function will be * called later by the crypto callback with a proper return value @@ -198,6 +204,7 @@ void ovpn_encrypt_post(void *data, int ret) goto err;

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

switch (peer->sock->sock->sk->sk_protocol) { case IPPROTO_UDP: @@ -207,6 +214,8 @@ void ovpn_encrypt_post(void *data, int ret) /* no transport configured yet */ goto err; } + + ovpn_peer_stats_increment_tx(&peer->link_stats, orig_len); /* skb passed down the stack - don't free it */ skb = NULL; err: @@ -325,6 +334,7 @@ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev) goto drop; }

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

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

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

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

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

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

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

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

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

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

dev->netdev_ops = &ovpn_netdev_ops;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

This change implements the keepalive sending and timer expiring logic.

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

diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index ecc1d35b04248f7d5da99501777bee971c98b91f..19c4e4750c493cdf134f550c779d8b9dac0009ad 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -27,6 +27,33 @@ #include "skb.h" #include "socket.h"

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

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

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

+ if (ovpn_is_keepalive(skb)) { + net_dbg_ratelimited("%s: ping received from peer %u\n", + netdev_name(peer->ovpn->dev), + peer->id); + goto drop_nocount; + } + net_info_ratelimited("%s: unsupported protocol received from peer %u\n", netdev_name(peer->ovpn->dev), peer->id); goto drop; @@ -146,6 +183,7 @@ void ovpn_decrypt_post(void *data, int ret) drop: if (unlikely(skb)) dev_core_stats_rx_dropped_inc(peer->ovpn->dev); +drop_nocount: if (likely(peer)) ovpn_peer_put(peer); if (likely(ks)) @@ -220,6 +258,8 @@ void ovpn_encrypt_post(void *data, int ret) }

ovpn_peer_stats_increment_tx(&peer->link_stats, orig_len); + /* keep track of last sent packet for keepalive */ + WRITE_ONCE(peer->last_sent, ktime_get_real_seconds()); /* skb passed down the stack - don't free it */ skb = NULL; err: @@ -349,3 +389,40 @@ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev) kfree_skb_list(skb); return NET_XMIT_DROP; } + +/** + * ovpn_xmit_special - encrypt and transmit an out-of-band message to peer + * @peer: peer to send the message to + * @data: message content + * @len: message length + * + * Assumes that caller holds a reference to peer + */ +void ovpn_xmit_special(struct ovpn_peer *peer, const void *data, + const unsigned int len) +{ + struct ovpn_priv *ovpn; + struct sk_buff *skb; + + ovpn = peer->ovpn; + if (unlikely(!ovpn)) + return; + + skb = alloc_skb(256 + len, GFP_ATOMIC); + if (unlikely(!skb)) + return; + + skb_reserve(skb, 128); + skb->priority = TC_PRIO_BESTEFFORT; + __skb_put_data(skb, data, len); + + /* increase reference counter when passing peer to sending queue */ + if (!ovpn_peer_hold(peer)) { + netdev_dbg(ovpn->dev, + "cannot hold peer reference for sending special packet\n"); + kfree_skb(skb); + return; + } + + ovpn_send(ovpn, skb, peer); +} diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h index 5f9c7eba37b132bcf8c0ebad60af9171e46bf3e8..1186bb6a5f1b0411a825a295d0e6e21c32972e84 100644 --- a/drivers/net/ovpn/io.h +++ b/drivers/net/ovpn/io.h @@ -19,9 +19,14 @@ /* max padding required by encryption */ #define OVPN_MAX_PADDING 16

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

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

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

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

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

#endif /* _NET_OVPN_OVPNSTRUCT_H_ */ diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index 5e78c984ef302ae17ef8481bb10ac382e5d11e31..168cec1cbcead962e921d29822fc0d9dec1f28a4 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -22,6 +22,46 @@ #include "peer.h" #include "socket.h"

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

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

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

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

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

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

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

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

- spin_lock_bh(&peer->lock); - old = rcu_replace_pointer(peer->bind, new, true); - spin_unlock_bh(&peer->lock); - - kfree_rcu(old, rcu); + kfree_rcu(rcu_replace_pointer(peer->bind, new, + lockdep_is_held(&peer->lock)), rcu); } diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 19c4e4750c493cdf134f550c779d8b9dac0009ad..b1e2f976b4cfdf1a6f8a644eb5406f21830026e6 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -134,6 +134,10 @@ void ovpn_decrypt_post(void *data, int ret) /* keep track of last received authenticated packet for keepalive */ WRITE_ONCE(peer->last_recv, ktime_get_real_seconds());

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

diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index decc80c095d6a82787d42d0b4d50f85016e942ba..2711ecdfdc767fd252e1cce9f6d2f37fa1535646 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -107,6 +107,191 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id) return peer; }

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

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

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

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

#endif /* _NET_OVPN_OVPNPEER_H_ */

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

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

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

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

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

void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs);

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

+enum ovpn_cipher_alg ovpn_aead_crypto_alg(struct ovpn_crypto_key_slot *ks); + #endif /* _NET_OVPN_OVPNAEAD_H_ */ diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c index 6b78137a8a43e7e030308a61e73739454009aa03..f4dfcaafdb9501999d25464a4ec9f096a16826c2 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -17,6 +17,7 @@ #include "netlink.h" #include "netlink-gen.h" #include "bind.h" +#include "crypto.h" #include "peer.h" #include "socket.h"

@@ -731,24 +732,316 @@ int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info) return ret; }

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

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

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

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

/**

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

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

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

diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c index 355cd3aa4849b518bc794152e6d9d0bce7ed0f6b..20e9d6b5e92c2647b00f8d50f508b5b1bd8d83d2 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -1044,6 +1044,61 @@ int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info) return 0; }

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

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

#endif /* _NET_OVPN_NETLINK_H_ */ diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index 86caac747c6173672e4d3294639f60cd4138ac43..513b738364b9281861ea6b83a6330e78cbea5f4f 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -995,6 +995,7 @@ static void ovpn_peer_remove(struct ovpn_peer *peer, }

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

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

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

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

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

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

Cc: linux-kselftest@vger.kernel.org Signed-off-by: Antonio Quartulli antonio@openvpn.net Reviewed-by: Shuah Khan skhan@linuxfoundation.org --- MAINTAINERS | 1 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/net/ovpn/.gitignore | 2 + tools/testing/selftests/net/ovpn/Makefile | 17 + tools/testing/selftests/net/ovpn/config | 10 + tools/testing/selftests/net/ovpn/data64.key | 5 + tools/testing/selftests/net/ovpn/ovpn-cli.c | 2370 ++++++++++++++++++++ tools/testing/selftests/net/ovpn/tcp_peers.txt | 5 + .../testing/selftests/net/ovpn/test-chachapoly.sh | 9 + tools/testing/selftests/net/ovpn/test-float.sh | 9 + tools/testing/selftests/net/ovpn/test-tcp.sh | 9 + tools/testing/selftests/net/ovpn/test.sh | 182 ++ tools/testing/selftests/net/ovpn/udp_peers.txt | 5 + 13 files changed, 2625 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS index 848538c52a01d18e0031ab34dca24c1151de4b8b..76b4c8f1e4a12bbbb8bc6c9344a0950656072571 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17481,6 +17481,7 @@ T: git https://github.com/OpenVPN/linux-kernel-ovpn.git F: Documentation/netlink/specs/ovpn.yaml F: drivers/net/ovpn/ F: include/uapi/linux/ovpn.h +F: tools/testing/selftests/net/ovpn/

OPENVSWITCH M: Pravin B Shelar pshelar@ovn.org diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 2401e973c35963c415c1041bc622f06c8a7ec251..e8363c21074c5f4f1cf4140369e7e1c15ec470bf 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -68,6 +68,7 @@ TARGETS += net/hsr TARGETS += net/mptcp TARGETS += net/netfilter TARGETS += net/openvswitch +TARGETS += net/ovpn TARGETS += net/packetdrill TARGETS += net/rds TARGETS += net/tcp_ao diff --git a/tools/testing/selftests/net/ovpn/.gitignore b/tools/testing/selftests/net/ovpn/.gitignore new file mode 100644 index 0000000000000000000000000000000000000000..ee44c081ca7c089933659689303c303a9fa9713b --- /dev/null +++ b/tools/testing/selftests/net/ovpn/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0+ +ovpn-cli diff --git a/tools/testing/selftests/net/ovpn/Makefile b/tools/testing/selftests/net/ovpn/Makefile new file mode 100644 index 0000000000000000000000000000000000000000..c76d8fd953c5674941c8c2787813063b1bce180f --- /dev/null +++ b/tools/testing/selftests/net/ovpn/Makefile @@ -0,0 +1,17 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020-2024 OpenVPN, Inc. +# +CFLAGS = -pedantic -Wextra -Wall -Wl,--no-as-needed -g -O0 -ggdb $(KHDR_INCLUDES) +CFLAGS += $(shell pkg-config --cflags libnl-3.0 libnl-genl-3.0) + +LDFLAGS = -lmbedtls -lmbedcrypto +LDFLAGS += $(shell pkg-config --libs libnl-3.0 libnl-genl-3.0) + +TEST_PROGS = test.sh \ + test-chachapoly.sh \ + test-tcp.sh \ + test-float.sh + +TEST_GEN_FILES = ovpn-cli + +include ../../lib.mk diff --git a/tools/testing/selftests/net/ovpn/config b/tools/testing/selftests/net/ovpn/config new file mode 100644 index 0000000000000000000000000000000000000000..71946ba9fa175c191725e369eb9b973503d9d9c4 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/config @@ -0,0 +1,10 @@ +CONFIG_NET=y +CONFIG_INET=y +CONFIG_STREAM_PARSER=y +CONFIG_NET_UDP_TUNNEL=y +CONFIG_DST_CACHE=y +CONFIG_CRYPTO=y +CONFIG_CRYPTO_AES=y +CONFIG_CRYPTO_GCM=y +CONFIG_CRYPTO_CHACHA20POLY1305=y +CONFIG_OVPN=m diff --git a/tools/testing/selftests/net/ovpn/data64.key b/tools/testing/selftests/net/ovpn/data64.key new file mode 100644 index 0000000000000000000000000000000000000000..a99e88c4e290f58b12f399b857b873f308d9ba09 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/data64.key @@ -0,0 +1,5 @@ +jRqMACN7d7/aFQNT8S7jkrBD8uwrgHbG5OQZP2eu4R1Y7tfpS2bf5RHv06Vi163CGoaIiTX99R3B +ia9ycAH8Wz1+9PWv51dnBLur9jbShlgZ2QHLtUc4a/gfT7zZwULXuuxdLnvR21DDeMBaTbkgbai9 +uvAa7ne1liIgGFzbv+Bas4HDVrygxIxuAnP5Qgc3648IJkZ0QEXPF+O9f0n5+QIvGCxkAUVx+5K6 +KIs+SoeWXnAopELmoGSjUpFtJbagXK82HfdqpuUxT2Tnuef0/14SzVE/vNleBNu2ZbyrSAaah8tE +BofkPJUBFY+YQcfZNM5Dgrw3i+Bpmpq/gpdg5w== diff --git a/tools/testing/selftests/net/ovpn/ovpn-cli.c b/tools/testing/selftests/net/ovpn/ovpn-cli.c new file mode 100644 index 0000000000000000000000000000000000000000..046dd069aaaf4e5b091947bd57ed79f8519a780f --- /dev/null +++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c @@ -0,0 +1,2370 @@ +// SPDX-License-Identifier: GPL-2.0 +/* OpenVPN data channel accelerator + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli antonio@openvpn.net + */ + +#include <stdio.h> +#include <inttypes.h> +#include <stdbool.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <arpa/inet.h> +#include <net/if.h> +#include <netinet/in.h> +#include <time.h> + +#include <linux/ovpn.h> +#include <linux/types.h> +#include <linux/netlink.h> + +#include <netlink/socket.h> +#include <netlink/netlink.h> +#include <netlink/genl/genl.h> +#include <netlink/genl/family.h> +#include <netlink/genl/ctrl.h> + +#include <mbedtls/base64.h> +#include <mbedtls/error.h> + +#include <sys/socket.h> + +/* defines to make checkpatch happy */ +#define strscpy strncpy +#define __always_unused __attribute__((__unused__)) + +/* libnl < 3.5.0 does not set the NLA_F_NESTED on its own, therefore we + * have to explicitly do it to prevent the kernel from failing upon + * parsing of the message + */ +#define nla_nest_start(_msg, _type) \ + nla_nest_start(_msg, (_type) | NLA_F_NESTED) + +uint64_t nla_get_uint(struct nlattr *attr) +{ + if (nla_len(attr) == sizeof(uint32_t)) + return nla_get_u32(attr); + else + return nla_get_u64(attr); +} + +typedef int (*ovpn_nl_cb)(struct nl_msg *msg, void *arg); + +enum ovpn_key_direction { + KEY_DIR_IN = 0, + KEY_DIR_OUT, +}; + +#define KEY_LEN (256 / 8) +#define NONCE_LEN 8 + +#define PEER_ID_UNDEF 0x00FFFFFF + +struct nl_ctx { + struct nl_sock *nl_sock; + struct nl_msg *nl_msg; + struct nl_cb *nl_cb; + + int ovpn_dco_id; +}; + +enum ovpn_cmd { + CMD_INVALID, + CMD_NEW_IFACE, + CMD_DEL_IFACE, + CMD_LISTEN, + CMD_CONNECT, + CMD_NEW_PEER, + CMD_NEW_MULTI_PEER, + CMD_SET_PEER, + CMD_DEL_PEER, + CMD_GET_PEER, + CMD_NEW_KEY, + CMD_DEL_KEY, + CMD_GET_KEY, + CMD_SWAP_KEYS, + CMD_LISTEN_MCAST, +}; + +struct ovpn_ctx { + enum ovpn_cmd cmd; + + __u8 key_enc[KEY_LEN]; + __u8 key_dec[KEY_LEN]; + __u8 nonce[NONCE_LEN]; + + enum ovpn_cipher_alg cipher; + + sa_family_t sa_family; + + unsigned long peer_id; + unsigned long lport; + + union { + struct sockaddr_in in4; + struct sockaddr_in6 in6; + } remote; + + union { + struct sockaddr_in in4; + struct sockaddr_in6 in6; + } peer_ip; + + bool peer_ip_set; + + unsigned int ifindex; + char ifname[IFNAMSIZ]; + enum ovpn_mode mode; + bool mode_set; + + int socket; + int cli_socket; + + __u32 keepalive_interval; + __u32 keepalive_timeout; + + enum ovpn_key_direction key_dir; + enum ovpn_key_slot key_slot; + int key_id; + + const char *peers_file; +}; + +static int ovpn_nl_recvmsgs(struct nl_ctx *ctx) +{ + int ret; + + ret = nl_recvmsgs(ctx->nl_sock, ctx->nl_cb); + + switch (ret) { + case -NLE_INTR: + fprintf(stderr, + "netlink received interrupt due to signal - ignoring\n"); + break; + case -NLE_NOMEM: + fprintf(stderr, "netlink out of memory error\n"); + break; + case -NLE_AGAIN: + fprintf(stderr, + "netlink reports blocking read - aborting wait\n"); + break; + default: + if (ret) + fprintf(stderr, "netlink reports error (%d): %s\n", + ret, nl_geterror(-ret)); + break; + } + + return ret; +} + +static struct nl_ctx *nl_ctx_alloc_flags(struct ovpn_ctx *ovpn, int cmd, + int flags) +{ + struct nl_ctx *ctx; + int err, ret; + + ctx = calloc(1, sizeof(*ctx)); + if (!ctx) + return NULL; + + ctx->nl_sock = nl_socket_alloc(); + if (!ctx->nl_sock) { + fprintf(stderr, "cannot allocate netlink socket\n"); + goto err_free; + } + + nl_socket_set_buffer_size(ctx->nl_sock, 8192, 8192); + + ret = genl_connect(ctx->nl_sock); + if (ret) { + fprintf(stderr, "cannot connect to generic netlink: %s\n", + nl_geterror(ret)); + goto err_sock; + } + + /* enable Extended ACK for detailed error reporting */ + err = 1; + setsockopt(nl_socket_get_fd(ctx->nl_sock), SOL_NETLINK, NETLINK_EXT_ACK, + &err, sizeof(err)); + + ctx->ovpn_dco_id = genl_ctrl_resolve(ctx->nl_sock, OVPN_FAMILY_NAME); + if (ctx->ovpn_dco_id < 0) { + fprintf(stderr, "cannot find ovpn_dco netlink component: %d\n", + ctx->ovpn_dco_id); + goto err_free; + } + + ctx->nl_msg = nlmsg_alloc(); + if (!ctx->nl_msg) { + fprintf(stderr, "cannot allocate netlink message\n"); + goto err_sock; + } + + ctx->nl_cb = nl_cb_alloc(NL_CB_DEFAULT); + if (!ctx->nl_cb) { + fprintf(stderr, "failed to allocate netlink callback\n"); + goto err_msg; + } + + nl_socket_set_cb(ctx->nl_sock, ctx->nl_cb); + + genlmsg_put(ctx->nl_msg, 0, 0, ctx->ovpn_dco_id, 0, flags, cmd, 0); + + if (ovpn->ifindex > 0) + NLA_PUT_U32(ctx->nl_msg, OVPN_A_IFINDEX, ovpn->ifindex); + + return ctx; +nla_put_failure: +err_msg: + nlmsg_free(ctx->nl_msg); +err_sock: + nl_socket_free(ctx->nl_sock); +err_free: + free(ctx); + return NULL; +} + +static struct nl_ctx *nl_ctx_alloc(struct ovpn_ctx *ovpn, int cmd) +{ + return nl_ctx_alloc_flags(ovpn, cmd, 0); +} + +static void nl_ctx_free(struct nl_ctx *ctx) +{ + if (!ctx) + return; + + nl_socket_free(ctx->nl_sock); + nlmsg_free(ctx->nl_msg); + nl_cb_put(ctx->nl_cb); + free(ctx); +} + +static int ovpn_nl_cb_error(struct sockaddr_nl (*nla)__always_unused, + struct nlmsgerr *err, void *arg) +{ + struct nlmsghdr *nlh = (struct nlmsghdr *)err - 1; + struct nlattr *tb_msg[NLMSGERR_ATTR_MAX + 1]; + int len = nlh->nlmsg_len; + struct nlattr *attrs; + int *ret = arg; + int ack_len = sizeof(*nlh) + sizeof(int) + sizeof(*nlh); + + *ret = err->error; + + if (!(nlh->nlmsg_flags & NLM_F_ACK_TLVS)) + return NL_STOP; + + if (!(nlh->nlmsg_flags & NLM_F_CAPPED)) + ack_len += err->msg.nlmsg_len - sizeof(*nlh); + + if (len <= ack_len) + return NL_STOP; + + attrs = (void *)((uint8_t *)nlh + ack_len); + len -= ack_len; + + nla_parse(tb_msg, NLMSGERR_ATTR_MAX, attrs, len, NULL); + if (tb_msg[NLMSGERR_ATTR_MSG]) { + len = strnlen((char *)nla_data(tb_msg[NLMSGERR_ATTR_MSG]), + nla_len(tb_msg[NLMSGERR_ATTR_MSG])); + fprintf(stderr, "kernel error: %*s\n", len, + (char *)nla_data(tb_msg[NLMSGERR_ATTR_MSG])); + } + + if (tb_msg[NLMSGERR_ATTR_MISS_NEST]) { + fprintf(stderr, "missing required nesting type %u\n", + nla_get_u32(tb_msg[NLMSGERR_ATTR_MISS_NEST])); + } + + if (tb_msg[NLMSGERR_ATTR_MISS_TYPE]) { + fprintf(stderr, "missing required attribute type %u\n", + nla_get_u32(tb_msg[NLMSGERR_ATTR_MISS_TYPE])); + } + + return NL_STOP; +} + +static int ovpn_nl_cb_finish(struct nl_msg (*msg)__always_unused, + void *arg) +{ + int *status = arg; + + *status = 0; + return NL_SKIP; +} + +static int ovpn_nl_cb_ack(struct nl_msg (*msg)__always_unused, + void *arg) +{ + int *status = arg; + + *status = 0; + return NL_STOP; +} + +static int ovpn_nl_msg_send(struct nl_ctx *ctx, ovpn_nl_cb cb) +{ + int status = 1; + + nl_cb_err(ctx->nl_cb, NL_CB_CUSTOM, ovpn_nl_cb_error, &status); + nl_cb_set(ctx->nl_cb, NL_CB_FINISH, NL_CB_CUSTOM, ovpn_nl_cb_finish, + &status); + nl_cb_set(ctx->nl_cb, NL_CB_ACK, NL_CB_CUSTOM, ovpn_nl_cb_ack, &status); + + if (cb) + nl_cb_set(ctx->nl_cb, NL_CB_VALID, NL_CB_CUSTOM, cb, ctx); + + nl_send_auto_complete(ctx->nl_sock, ctx->nl_msg); + + while (status == 1) + ovpn_nl_recvmsgs(ctx); + + if (status < 0) + fprintf(stderr, "failed to send netlink message: %s (%d)\n", + strerror(-status), status); + + return status; +} + +static int ovpn_parse_key(const char *file, struct ovpn_ctx *ctx) +{ + int idx_enc, idx_dec, ret = -1; + unsigned char *ckey = NULL; + __u8 *bkey = NULL; + size_t olen = 0; + long ckey_len; + FILE *fp; + + fp = fopen(file, "r"); + if (!fp) { + fprintf(stderr, "cannot open: %s\n", file); + return -1; + } + + /* get file size */ + fseek(fp, 0L, SEEK_END); + ckey_len = ftell(fp); + rewind(fp); + + /* if the file is longer, let's just read a portion */ + if (ckey_len > 256) + ckey_len = 256; + + ckey = malloc(ckey_len); + if (!ckey) + goto err; + + ret = fread(ckey, 1, ckey_len, fp); + if (ret != ckey_len) { + fprintf(stderr, + "couldn't read enough data from key file: %dbytes read\n", + ret); + goto err; + } + + olen = 0; + ret = mbedtls_base64_decode(NULL, 0, &olen, ckey, ckey_len); + if (ret != MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL) { + char buf[256]; + + mbedtls_strerror(ret, buf, sizeof(buf)); + fprintf(stderr, "unexpected base64 error1: %s (%d)\n", buf, + ret); + + goto err; + } + + bkey = malloc(olen); + if (!bkey) { + fprintf(stderr, "cannot allocate binary key buffer\n"); + goto err; + } + + ret = mbedtls_base64_decode(bkey, olen, &olen, ckey, ckey_len); + if (ret) { + char buf[256]; + + mbedtls_strerror(ret, buf, sizeof(buf)); + fprintf(stderr, "unexpected base64 error2: %s (%d)\n", buf, + ret); + + goto err; + } + + if (olen < 2 * KEY_LEN + NONCE_LEN) { + fprintf(stderr, + "not enough data in key file, found %zdB but needs %dB\n", + olen, 2 * KEY_LEN + NONCE_LEN); + goto err; + } + + switch (ctx->key_dir) { + case KEY_DIR_IN: + idx_enc = 0; + idx_dec = 1; + break; + case KEY_DIR_OUT: + idx_enc = 1; + idx_dec = 0; + break; + default: + goto err; + } + + memcpy(ctx->key_enc, bkey + KEY_LEN * idx_enc, KEY_LEN); + memcpy(ctx->key_dec, bkey + KEY_LEN * idx_dec, KEY_LEN); + memcpy(ctx->nonce, bkey + 2 * KEY_LEN, NONCE_LEN); + + ret = 0; + +err: + fclose(fp); + free(bkey); + free(ckey); + + return ret; +} + +static int ovpn_parse_cipher(const char *cipher, struct ovpn_ctx *ctx) +{ + if (strcmp(cipher, "aes") == 0) + ctx->cipher = OVPN_CIPHER_ALG_AES_GCM; + else if (strcmp(cipher, "chachapoly") == 0) + ctx->cipher = OVPN_CIPHER_ALG_CHACHA20_POLY1305; + else if (strcmp(cipher, "none") == 0) + ctx->cipher = OVPN_CIPHER_ALG_NONE; + else + return -ENOTSUP; + + return 0; +} + +static int ovpn_parse_key_direction(const char *dir, struct ovpn_ctx *ctx) +{ + int in_dir; + + in_dir = strtoll(dir, NULL, 10); + switch (in_dir) { + case KEY_DIR_IN: + case KEY_DIR_OUT: + ctx->key_dir = in_dir; + break; + default: + fprintf(stderr, + "invalid key direction provided. Can be 0 or 1 only\n"); + return -1; + } + + return 0; +} + +static int ovpn_socket(struct ovpn_ctx *ctx, sa_family_t family, int proto) +{ + struct sockaddr_storage local_sock = { 0 }; + struct sockaddr_in6 *in6; + struct sockaddr_in *in; + int ret, s, sock_type; + size_t sock_len; + + if (proto == IPPROTO_UDP) + sock_type = SOCK_DGRAM; + else if (proto == IPPROTO_TCP) + sock_type = SOCK_STREAM; + else + return -EINVAL; + + s = socket(family, sock_type, 0); + if (s < 0) { + perror("cannot create socket"); + return -1; + } + + switch (family) { + case AF_INET: + in = (struct sockaddr_in *)&local_sock; + in->sin_family = family; + in->sin_port = htons(ctx->lport); + in->sin_addr.s_addr = htonl(INADDR_ANY); + sock_len = sizeof(*in); + break; + case AF_INET6: + in6 = (struct sockaddr_in6 *)&local_sock; + in6->sin6_family = family; + in6->sin6_port = htons(ctx->lport); + in6->sin6_addr = in6addr_any; + sock_len = sizeof(*in6); + break; + default: + return -1; + } + + int opt = 1; + + ret = setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)); + + if (ret < 0) { + perror("setsockopt for SO_REUSEADDR"); + return ret; + } + + ret = setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(opt)); + if (ret < 0) { + perror("setsockopt for SO_REUSEPORT"); + return ret; + } + + if (family == AF_INET6) { + opt = 0; + if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &opt, + sizeof(opt))) { + perror("failed to set IPV6_V6ONLY"); + return -1; + } + } + + ret = bind(s, (struct sockaddr *)&local_sock, sock_len); + if (ret < 0) { + perror("cannot bind socket"); + goto err_socket; + } + + ctx->socket = s; + ctx->sa_family = family; + return 0; + +err_socket: + close(s); + return -1; +} + +static int ovpn_udp_socket(struct ovpn_ctx *ctx, sa_family_t family) +{ + return ovpn_socket(ctx, family, IPPROTO_UDP); +} + +static int ovpn_listen(struct ovpn_ctx *ctx, sa_family_t family) +{ + int ret; + + ret = ovpn_socket(ctx, family, IPPROTO_TCP); + if (ret < 0) + return ret; + + ret = listen(ctx->socket, 10); + if (ret < 0) { + perror("listen"); + close(ctx->socket); + return -1; + } + + return 0; +} + +static int ovpn_accept(struct ovpn_ctx *ctx) +{ + socklen_t socklen; + int ret; + + socklen = sizeof(ctx->remote); + ret = accept(ctx->socket, (struct sockaddr *)&ctx->remote, &socklen); + if (ret < 0) { + perror("accept"); + goto err; + } + + fprintf(stderr, "Connection received!\n"); + + switch (socklen) { + case sizeof(struct sockaddr_in): + case sizeof(struct sockaddr_in6): + break; + default: + fprintf(stderr, "error: expecting IPv4 or IPv6 connection\n"); + close(ret); + ret = -EINVAL; + goto err; + } + + return ret; +err: + close(ctx->socket); + return ret; +} + +static int ovpn_connect(struct ovpn_ctx *ovpn) +{ + socklen_t socklen; + int s, ret; + + s = socket(ovpn->remote.in4.sin_family, SOCK_STREAM, 0); + if (s < 0) { + perror("cannot create socket"); + return -1; + } + + switch (ovpn->remote.in4.sin_family) { + case AF_INET: + socklen = sizeof(struct sockaddr_in); + break; + case AF_INET6: + socklen = sizeof(struct sockaddr_in6); + break; + default: + return -EOPNOTSUPP; + } + + ret = connect(s, (struct sockaddr *)&ovpn->remote, socklen); + if (ret < 0) { + perror("connect"); + goto err; + } + + fprintf(stderr, "connected\n"); + + ovpn->socket = s; + + return 0; +err: + close(s); + return ret; +} + +static int ovpn_new_peer(struct ovpn_ctx *ovpn, bool is_tcp) +{ + struct nlattr *attr; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_NEW); + if (!ctx) + return -ENOMEM; + + attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_SOCKET, ovpn->socket); + + if (!is_tcp) { + switch (ovpn->remote.in4.sin_family) { + case AF_INET: + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_REMOTE_IPV4, + ovpn->remote.in4.sin_addr.s_addr); + NLA_PUT_U16(ctx->nl_msg, OVPN_A_PEER_REMOTE_PORT, + ovpn->remote.in4.sin_port); + break; + case AF_INET6: + NLA_PUT(ctx->nl_msg, OVPN_A_PEER_REMOTE_IPV6, + sizeof(ovpn->remote.in6.sin6_addr), + &ovpn->remote.in6.sin6_addr); + NLA_PUT_U32(ctx->nl_msg, + OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID, + ovpn->remote.in6.sin6_scope_id); + NLA_PUT_U16(ctx->nl_msg, OVPN_A_PEER_REMOTE_PORT, + ovpn->remote.in6.sin6_port); + break; + default: + fprintf(stderr, + "Invalid family for remote socket address\n"); + goto nla_put_failure; + } + } + + if (ovpn->peer_ip_set) { + switch (ovpn->peer_ip.in4.sin_family) { + case AF_INET: + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_VPN_IPV4, + ovpn->peer_ip.in4.sin_addr.s_addr); + break; + case AF_INET6: + NLA_PUT(ctx->nl_msg, OVPN_A_PEER_VPN_IPV6, + sizeof(struct in6_addr), + &ovpn->peer_ip.in6.sin6_addr); + break; + default: + fprintf(stderr, "Invalid family for peer address\n"); + goto nla_put_failure; + } + } + + nla_nest_end(ctx->nl_msg, attr); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_set_peer(struct ovpn_ctx *ovpn) +{ + struct nlattr *attr; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_SET); + if (!ctx) + return -ENOMEM; + + attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_KEEPALIVE_INTERVAL, + ovpn->keepalive_interval); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_KEEPALIVE_TIMEOUT, + ovpn->keepalive_timeout); + nla_nest_end(ctx->nl_msg, attr); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_del_peer(struct ovpn_ctx *ovpn) +{ + struct nlattr *attr; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_DEL); + if (!ctx) + return -ENOMEM; + + attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id); + nla_nest_end(ctx->nl_msg, attr); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_handle_peer(struct nl_msg *msg, void (*arg)__always_unused) +{ + struct nlattr *pattrs[OVPN_A_PEER_MAX + 1]; + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *attrs[OVPN_A_MAX + 1]; + __u16 rport = 0, lport = 0; + + nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL); + + if (!attrs[OVPN_A_PEER]) { + fprintf(stderr, "no packet content in netlink message\n"); + return NL_SKIP; + } + + nla_parse(pattrs, OVPN_A_PEER_MAX, nla_data(attrs[OVPN_A_PEER]), + nla_len(attrs[OVPN_A_PEER]), NULL); + + if (pattrs[OVPN_A_PEER_ID]) + fprintf(stderr, "* Peer %u\n", + nla_get_u32(pattrs[OVPN_A_PEER_ID])); + + if (pattrs[OVPN_A_PEER_VPN_IPV4]) { + char buf[INET_ADDRSTRLEN]; + + inet_ntop(AF_INET, nla_data(pattrs[OVPN_A_PEER_VPN_IPV4]), + buf, sizeof(buf)); + fprintf(stderr, "\tVPN IPv4: %s\n", buf); + } + + if (pattrs[OVPN_A_PEER_VPN_IPV6]) { + char buf[INET6_ADDRSTRLEN]; + + inet_ntop(AF_INET6, nla_data(pattrs[OVPN_A_PEER_VPN_IPV6]), + buf, sizeof(buf)); + fprintf(stderr, "\tVPN IPv6: %s\n", buf); + } + + if (pattrs[OVPN_A_PEER_LOCAL_PORT]) + lport = ntohs(nla_get_u16(pattrs[OVPN_A_PEER_LOCAL_PORT])); + + if (pattrs[OVPN_A_PEER_REMOTE_PORT]) + rport = ntohs(nla_get_u16(pattrs[OVPN_A_PEER_REMOTE_PORT])); + + if (pattrs[OVPN_A_PEER_REMOTE_IPV6]) { + void *ip = pattrs[OVPN_A_PEER_REMOTE_IPV6]; + char buf[INET6_ADDRSTRLEN]; + int scope_id = -1; + + if (pattrs[OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID]) { + void *p = pattrs[OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID]; + + scope_id = nla_get_u32(p); + } + + inet_ntop(AF_INET6, nla_data(ip), buf, sizeof(buf)); + fprintf(stderr, "\tRemote: %s:%hu (scope-id: %u)\n", buf, rport, + scope_id); + + if (pattrs[OVPN_A_PEER_LOCAL_IPV6]) { + void *ip = pattrs[OVPN_A_PEER_LOCAL_IPV6]; + + inet_ntop(AF_INET6, nla_data(ip), buf, sizeof(buf)); + fprintf(stderr, "\tLocal: %s:%hu\n", buf, lport); + } + } + + if (pattrs[OVPN_A_PEER_REMOTE_IPV4]) { + void *ip = pattrs[OVPN_A_PEER_REMOTE_IPV4]; + char buf[INET_ADDRSTRLEN]; + + inet_ntop(AF_INET, nla_data(ip), buf, sizeof(buf)); + fprintf(stderr, "\tRemote: %s:%hu\n", buf, rport); + + if (pattrs[OVPN_A_PEER_LOCAL_IPV4]) { + void *p = pattrs[OVPN_A_PEER_LOCAL_IPV4]; + + inet_ntop(AF_INET, nla_data(p), buf, sizeof(buf)); + fprintf(stderr, "\tLocal: %s:%hu\n", buf, lport); + } + } + + if (pattrs[OVPN_A_PEER_KEEPALIVE_INTERVAL]) { + void *p = pattrs[OVPN_A_PEER_KEEPALIVE_INTERVAL]; + + fprintf(stderr, "\tKeepalive interval: %u sec\n", + nla_get_u32(p)); + } + + if (pattrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT]) + fprintf(stderr, "\tKeepalive timeout: %u sec\n", + nla_get_u32(pattrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT])); + + if (pattrs[OVPN_A_PEER_VPN_RX_BYTES]) + fprintf(stderr, "\tVPN RX bytes: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_VPN_RX_BYTES])); + + if (pattrs[OVPN_A_PEER_VPN_TX_BYTES]) + fprintf(stderr, "\tVPN TX bytes: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_VPN_TX_BYTES])); + + if (pattrs[OVPN_A_PEER_VPN_RX_PACKETS]) + fprintf(stderr, "\tVPN RX packets: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_VPN_RX_PACKETS])); + + if (pattrs[OVPN_A_PEER_VPN_TX_PACKETS]) + fprintf(stderr, "\tVPN TX packets: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_VPN_TX_PACKETS])); + + if (pattrs[OVPN_A_PEER_LINK_RX_BYTES]) + fprintf(stderr, "\tLINK RX bytes: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_LINK_RX_BYTES])); + + if (pattrs[OVPN_A_PEER_LINK_TX_BYTES]) + fprintf(stderr, "\tLINK TX bytes: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_LINK_TX_BYTES])); + + if (pattrs[OVPN_A_PEER_LINK_RX_PACKETS]) + fprintf(stderr, "\tLINK RX packets: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_LINK_RX_PACKETS])); + + if (pattrs[OVPN_A_PEER_LINK_TX_PACKETS]) + fprintf(stderr, "\tLINK TX packets: %" PRIu64 "\n", + nla_get_uint(pattrs[OVPN_A_PEER_LINK_TX_PACKETS])); + + return NL_SKIP; +} + +static int ovpn_get_peer(struct ovpn_ctx *ovpn) +{ + int flags = 0, ret = -1; + struct nlattr *attr; + struct nl_ctx *ctx; + + if (ovpn->peer_id == PEER_ID_UNDEF) + flags = NLM_F_DUMP; + + ctx = nl_ctx_alloc_flags(ovpn, OVPN_CMD_PEER_GET, flags); + if (!ctx) + return -ENOMEM; + + if (ovpn->peer_id != PEER_ID_UNDEF) { + attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id); + nla_nest_end(ctx->nl_msg, attr); + } + + ret = ovpn_nl_msg_send(ctx, ovpn_handle_peer); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_new_key(struct ovpn_ctx *ovpn) +{ + struct nlattr *keyconf, *key_dir; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_NEW); + if (!ctx) + return -ENOMEM; + + keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_KEY_ID, ovpn->key_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_CIPHER_ALG, ovpn->cipher); + + key_dir = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF_ENCRYPT_DIR); + NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_CIPHER_KEY, KEY_LEN, ovpn->key_enc); + NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_NONCE_TAIL, NONCE_LEN, ovpn->nonce); + nla_nest_end(ctx->nl_msg, key_dir); + + key_dir = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF_DECRYPT_DIR); + NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_CIPHER_KEY, KEY_LEN, ovpn->key_dec); + NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_NONCE_TAIL, NONCE_LEN, ovpn->nonce); + nla_nest_end(ctx->nl_msg, key_dir); + + nla_nest_end(ctx->nl_msg, keyconf); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_del_key(struct ovpn_ctx *ovpn) +{ + struct nlattr *keyconf; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_DEL); + if (!ctx) + return -ENOMEM; + + keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot); + nla_nest_end(ctx->nl_msg, keyconf); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_handle_key(struct nl_msg *msg, void (*arg)__always_unused) +{ + struct nlattr *kattrs[OVPN_A_KEYCONF_MAX + 1]; + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *attrs[OVPN_A_MAX + 1]; + + nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL); + + if (!attrs[OVPN_A_KEYCONF]) { + fprintf(stderr, "no packet content in netlink message\n"); + return NL_SKIP; + } + + nla_parse(kattrs, OVPN_A_KEYCONF_MAX, nla_data(attrs[OVPN_A_KEYCONF]), + nla_len(attrs[OVPN_A_KEYCONF]), NULL); + + if (kattrs[OVPN_A_KEYCONF_PEER_ID]) + fprintf(stderr, "* Peer %u\n", + nla_get_u32(kattrs[OVPN_A_KEYCONF_PEER_ID])); + if (kattrs[OVPN_A_KEYCONF_SLOT]) { + fprintf(stderr, "\t- Slot: "); + switch (nla_get_u32(kattrs[OVPN_A_KEYCONF_SLOT])) { + case OVPN_KEY_SLOT_PRIMARY: + fprintf(stderr, "primary\n"); + break; + case OVPN_KEY_SLOT_SECONDARY: + fprintf(stderr, "secondary\n"); + break; + default: + fprintf(stderr, "invalid (%u)\n", + nla_get_u32(kattrs[OVPN_A_KEYCONF_SLOT])); + break; + } + } + if (kattrs[OVPN_A_KEYCONF_KEY_ID]) + fprintf(stderr, "\t- Key ID: %u\n", + nla_get_u32(kattrs[OVPN_A_KEYCONF_KEY_ID])); + if (kattrs[OVPN_A_KEYCONF_CIPHER_ALG]) { + fprintf(stderr, "\t- Cipher: "); + switch (nla_get_u32(kattrs[OVPN_A_KEYCONF_CIPHER_ALG])) { + case OVPN_CIPHER_ALG_NONE: + fprintf(stderr, "none\n"); + break; + case OVPN_CIPHER_ALG_AES_GCM: + fprintf(stderr, "aes-gcm\n"); + break; + case OVPN_CIPHER_ALG_CHACHA20_POLY1305: + fprintf(stderr, "chacha20poly1305\n"); + break; + default: + fprintf(stderr, "invalid (%u)\n", + nla_get_u32(kattrs[OVPN_A_KEYCONF_CIPHER_ALG])); + break; + } + } + + return NL_SKIP; +} + +static int ovpn_get_key(struct ovpn_ctx *ovpn) +{ + struct nlattr *keyconf; + struct nl_ctx *ctx; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_GET); + if (!ctx) + return -ENOMEM; + + keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot); + nla_nest_end(ctx->nl_msg, keyconf); + + ret = ovpn_nl_msg_send(ctx, ovpn_handle_key); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +static int ovpn_swap_keys(struct ovpn_ctx *ovpn) +{ + struct nl_ctx *ctx; + struct nlattr *kc; + int ret = -1; + + ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_SWAP); + if (!ctx) + return -ENOMEM; + + kc = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF); + NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id); + nla_nest_end(ctx->nl_msg, kc); + + ret = ovpn_nl_msg_send(ctx, NULL); +nla_put_failure: + nl_ctx_free(ctx); + return ret; +} + +/** + * Helper function used to easily add attributes to a rtnl message + */ +static int ovpn_addattr(struct nlmsghdr *n, int maxlen, int type, + const void *data, int alen) +{ + int len = RTA_LENGTH(alen); + struct rtattr *rta; + + if ((int)(NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len)) > maxlen) { + fprintf(stderr, "%s: rtnl: message exceeded bound of %d\n", + __func__, maxlen); + return -EMSGSIZE; + } + + rta = nlmsg_tail(n); + rta->rta_type = type; + rta->rta_len = len; + + if (!data) + memset(RTA_DATA(rta), 0, alen); + else + memcpy(RTA_DATA(rta), data, alen); + + n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len); + + return 0; +} + +static struct rtattr *ovpn_nest_start(struct nlmsghdr *msg, size_t max_size, + int attr) +{ + struct rtattr *nest = nlmsg_tail(msg); + + if (ovpn_addattr(msg, max_size, attr, NULL, 0) < 0) + return NULL; + + return nest; +} + +static void ovpn_nest_end(struct nlmsghdr *msg, struct rtattr *nest) +{ + nest->rta_len = (uint8_t *)nlmsg_tail(msg) - (uint8_t *)nest; +} + +#define RT_SNDBUF_SIZE (1024 * 2) +#define RT_RCVBUF_SIZE (1024 * 4) + +/** + * Open RTNL socket + */ +static int ovpn_rt_socket(void) +{ + int sndbuf = RT_SNDBUF_SIZE, rcvbuf = RT_RCVBUF_SIZE, fd; + + fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (fd < 0) { + fprintf(stderr, "%s: cannot open netlink socket\n", __func__); + return fd; + } + + if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &sndbuf, + sizeof(sndbuf)) < 0) { + fprintf(stderr, "%s: SO_SNDBUF\n", __func__); + close(fd); + return -1; + } + + if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, + sizeof(rcvbuf)) < 0) { + fprintf(stderr, "%s: SO_RCVBUF\n", __func__); + close(fd); + return -1; + } + + return fd; +} + +/** + * Bind socket to Netlink subsystem + */ +static int ovpn_rt_bind(int fd, uint32_t groups) +{ + struct sockaddr_nl local = { 0 }; + socklen_t addr_len; + + local.nl_family = AF_NETLINK; + local.nl_groups = groups; + + if (bind(fd, (struct sockaddr *)&local, sizeof(local)) < 0) { + fprintf(stderr, "%s: cannot bind netlink socket: %d\n", + __func__, errno); + return -errno; + } + + addr_len = sizeof(local); + if (getsockname(fd, (struct sockaddr *)&local, &addr_len) < 0) { + fprintf(stderr, "%s: cannot getsockname: %d\n", __func__, + errno); + return -errno; + } + + if (addr_len != sizeof(local)) { + fprintf(stderr, "%s: wrong address length %d\n", __func__, + addr_len); + return -EINVAL; + } + + if (local.nl_family != AF_NETLINK) { + fprintf(stderr, "%s: wrong address family %d\n", __func__, + local.nl_family); + return -EINVAL; + } + + return 0; +} + +typedef int (*ovpn_parse_reply_cb)(struct nlmsghdr *msg, void *arg); + +/** + * Send Netlink message and run callback on reply (if specified) + */ +static int ovpn_rt_send(struct nlmsghdr *payload, pid_t peer, + unsigned int groups, ovpn_parse_reply_cb cb, + void *arg_cb) +{ + int len, rem_len, fd, ret, rcv_len; + struct sockaddr_nl nladdr = { 0 }; + struct nlmsgerr *err; + struct nlmsghdr *h; + char buf[1024 * 16]; + struct iovec iov = { + .iov_base = payload, + .iov_len = payload->nlmsg_len, + }; + struct msghdr nlmsg = { + .msg_name = &nladdr, + .msg_namelen = sizeof(nladdr), + .msg_iov = &iov, + .msg_iovlen = 1, + }; + + nladdr.nl_family = AF_NETLINK; + nladdr.nl_pid = peer; + nladdr.nl_groups = groups; + + payload->nlmsg_seq = time(NULL); + + /* no need to send reply */ + if (!cb) + payload->nlmsg_flags |= NLM_F_ACK; + + fd = ovpn_rt_socket(); + if (fd < 0) { + fprintf(stderr, "%s: can't open rtnl socket\n", __func__); + return -errno; + } + + ret = ovpn_rt_bind(fd, 0); + if (ret < 0) { + fprintf(stderr, "%s: can't bind rtnl socket\n", __func__); + ret = -errno; + goto out; + } + + ret = sendmsg(fd, &nlmsg, 0); + if (ret < 0) { + fprintf(stderr, "%s: rtnl: error on sendmsg()\n", __func__); + ret = -errno; + goto out; + } + + /* prepare buffer to store RTNL replies */ + memset(buf, 0, sizeof(buf)); + iov.iov_base = buf; + + while (1) { + /* + * iov_len is modified by recvmsg(), therefore has to be initialized before + * using it again + */ + iov.iov_len = sizeof(buf); + rcv_len = recvmsg(fd, &nlmsg, 0); + if (rcv_len < 0) { + if (errno == EINTR || errno == EAGAIN) { + fprintf(stderr, "%s: interrupted call\n", + __func__); + continue; + } + fprintf(stderr, "%s: rtnl: error on recvmsg()\n", + __func__); + ret = -errno; + goto out; + } + + if (rcv_len == 0) { + fprintf(stderr, + "%s: rtnl: socket reached unexpected EOF\n", + __func__); + ret = -EIO; + goto out; + } + + if (nlmsg.msg_namelen != sizeof(nladdr)) { + fprintf(stderr, + "%s: sender address length: %u (expected %zu)\n", + __func__, nlmsg.msg_namelen, sizeof(nladdr)); + ret = -EIO; + goto out; + } + + h = (struct nlmsghdr *)buf; + while (rcv_len >= (int)sizeof(*h)) { + len = h->nlmsg_len; + rem_len = len - sizeof(*h); + + if (rem_len < 0 || len > rcv_len) { + if (nlmsg.msg_flags & MSG_TRUNC) { + fprintf(stderr, "%s: truncated message\n", + __func__); + ret = -EIO; + goto out; + } + fprintf(stderr, "%s: malformed message: len=%d\n", + __func__, len); + ret = -EIO; + goto out; + } + + if (h->nlmsg_type == NLMSG_DONE) { + ret = 0; + goto out; + } + + if (h->nlmsg_type == NLMSG_ERROR) { + err = (struct nlmsgerr *)NLMSG_DATA(h); + if (rem_len < (int)sizeof(struct nlmsgerr)) { + fprintf(stderr, "%s: ERROR truncated\n", + __func__); + ret = -EIO; + goto out; + } + + if (err->error) { + fprintf(stderr, "%s: (%d) %s\n", + __func__, err->error, + strerror(-err->error)); + ret = err->error; + goto out; + } + + ret = 0; + if (cb) { + int r = cb(h, arg_cb); + + if (r <= 0) + ret = r; + } + goto out; + } + + if (cb) { + int r = cb(h, arg_cb); + + if (r <= 0) { + ret = r; + goto out; + } + } else { + fprintf(stderr, "%s: RTNL: unexpected reply\n", + __func__); + } + + rcv_len -= NLMSG_ALIGN(len); + h = (struct nlmsghdr *)((uint8_t *)h + + NLMSG_ALIGN(len)); + } + + if (nlmsg.msg_flags & MSG_TRUNC) { + fprintf(stderr, "%s: message truncated\n", __func__); + continue; + } + + if (rcv_len) { + fprintf(stderr, "%s: rtnl: %d not parsed bytes\n", + __func__, rcv_len); + ret = -1; + goto out; + } + } +out: + close(fd); + + return ret; +} + +struct ovpn_link_req { + struct nlmsghdr n; + struct ifinfomsg i; + char buf[256]; +}; + +static int ovpn_new_iface(struct ovpn_ctx *ovpn) +{ + struct rtattr *linkinfo, *data; + struct ovpn_link_req req = { 0 }; + int ret = -1; + + fprintf(stdout, "Creating interface %s with mode %u\n", ovpn->ifname, + ovpn->mode); + + req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i)); + req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL; + req.n.nlmsg_type = RTM_NEWLINK; + + if (ovpn_addattr(&req.n, sizeof(req), IFLA_IFNAME, ovpn->ifname, + strlen(ovpn->ifname) + 1) < 0) + goto err; + + linkinfo = ovpn_nest_start(&req.n, sizeof(req), IFLA_LINKINFO); + if (!linkinfo) + goto err; + + if (ovpn_addattr(&req.n, sizeof(req), IFLA_INFO_KIND, OVPN_FAMILY_NAME, + strlen(OVPN_FAMILY_NAME) + 1) < 0) + goto err; + + if (ovpn->mode_set) { + data = ovpn_nest_start(&req.n, sizeof(req), IFLA_INFO_DATA); + if (!data) + goto err; + + if (ovpn_addattr(&req.n, sizeof(req), IFLA_OVPN_MODE, + &ovpn->mode, sizeof(uint8_t)) < 0) + goto err; + + ovpn_nest_end(&req.n, data); + } + + ovpn_nest_end(&req.n, linkinfo); + + req.i.ifi_family = AF_PACKET; + + ret = ovpn_rt_send(&req.n, 0, 0, NULL, NULL); +err: + return ret; +} + +static int ovpn_del_iface(struct ovpn_ctx *ovpn) +{ + struct ovpn_link_req req = { 0 }; + + fprintf(stdout, "Deleting interface %s ifindex %u\n", ovpn->ifname, + ovpn->ifindex); + + req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i)); + req.n.nlmsg_flags = NLM_F_REQUEST; + req.n.nlmsg_type = RTM_DELLINK; + + req.i.ifi_family = AF_PACKET; + req.i.ifi_index = ovpn->ifindex; + + return ovpn_rt_send(&req.n, 0, 0, NULL, NULL); +} + +static int nl_seq_check(struct nl_msg (*msg)__always_unused, + void (*arg)__always_unused) +{ + return NL_OK; +} + +struct mcast_handler_args { + const char *group; + int id; +}; + +static int mcast_family_handler(struct nl_msg *msg, void *arg) +{ + struct mcast_handler_args *grp = arg; + struct nlattr *tb[CTRL_ATTR_MAX + 1]; + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *mcgrp; + int rem_mcgrp; + + nla_parse(tb, CTRL_ATTR_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL); + + if (!tb[CTRL_ATTR_MCAST_GROUPS]) + return NL_SKIP; + + nla_for_each_nested(mcgrp, tb[CTRL_ATTR_MCAST_GROUPS], rem_mcgrp) { + struct nlattr *tb_mcgrp[CTRL_ATTR_MCAST_GRP_MAX + 1]; + + nla_parse(tb_mcgrp, CTRL_ATTR_MCAST_GRP_MAX, + nla_data(mcgrp), nla_len(mcgrp), NULL); + + if (!tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME] || + !tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]) + continue; + if (strncmp(nla_data(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]), + grp->group, nla_len(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]))) + continue; + grp->id = nla_get_u32(tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]); + break; + } + + return NL_SKIP; +} + +static int mcast_error_handler(struct sockaddr_nl (*nla)__always_unused, + struct nlmsgerr *err, void *arg) +{ + int *ret = arg; + + *ret = err->error; + return NL_STOP; +} + +static int mcast_ack_handler(struct nl_msg (*msg)__always_unused, void *arg) +{ + int *ret = arg; + + *ret = 0; + return NL_STOP; +} + +static int ovpn_handle_msg(struct nl_msg *msg, void *arg) +{ + struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg)); + struct nlattr *attrs[OVPN_A_MAX + 1]; + struct nlmsghdr *nlh = nlmsg_hdr(msg); + //enum ovpn_del_peer_reason reason; + char ifname[IF_NAMESIZE]; + int *ret = arg; + __u32 ifindex; + + fprintf(stderr, "received message from ovpn-dco\n"); + + *ret = -1; + + if (!genlmsg_valid_hdr(nlh, 0)) { + fprintf(stderr, "invalid header\n"); + return NL_STOP; + } + + if (nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), NULL)) { + fprintf(stderr, "received bogus data from ovpn-dco\n"); + return NL_STOP; + } + + if (!attrs[OVPN_A_IFINDEX]) { + fprintf(stderr, "no ifindex in this message\n"); + return NL_STOP; + } + + ifindex = nla_get_u32(attrs[OVPN_A_IFINDEX]); + if (!if_indextoname(ifindex, ifname)) { + fprintf(stderr, "cannot resolve ifname for ifindex: %u\n", + ifindex); + return NL_STOP; + } + + switch (gnlh->cmd) { + case OVPN_CMD_PEER_DEL_NTF: + /*if (!attrs[OVPN_A_DEL_PEER_REASON]) { + * fprintf(stderr, "no reason in DEL_PEER message\n"); + * return NL_STOP; + *} + * + *reason = nla_get_u8(attrs[OVPN_A_DEL_PEER_REASON]); + *fprintf(stderr, + * "received CMD_DEL_PEER, ifname: %s reason: %d\n", + * ifname, reason); + */ + fprintf(stdout, "received CMD_PEER_DEL_NTF\n"); + break; + case OVPN_CMD_KEY_SWAP_NTF: + fprintf(stdout, "received CMD_KEY_SWAP_NTF\n"); + break; + default: + fprintf(stderr, "received unknown command: %d\n", gnlh->cmd); + return NL_STOP; + } + + *ret = 0; + return NL_OK; +} + +static int ovpn_get_mcast_id(struct nl_sock *sock, const char *family, + const char *group) +{ + struct nl_msg *msg; + struct nl_cb *cb; + int ret, ctrlid; + struct mcast_handler_args grp = { + .group = group, + .id = -ENOENT, + }; + + msg = nlmsg_alloc(); + if (!msg) + return -ENOMEM; + + cb = nl_cb_alloc(NL_CB_DEFAULT); + if (!cb) { + ret = -ENOMEM; + goto out_fail_cb; + } + + ctrlid = genl_ctrl_resolve(sock, "nlctrl"); + + genlmsg_put(msg, 0, 0, ctrlid, 0, 0, CTRL_CMD_GETFAMILY, 0); + + ret = -ENOBUFS; + NLA_PUT_STRING(msg, CTRL_ATTR_FAMILY_NAME, family); + + ret = nl_send_auto_complete(sock, msg); + if (ret < 0) + goto nla_put_failure; + + ret = 1; + + nl_cb_err(cb, NL_CB_CUSTOM, mcast_error_handler, &ret); + nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, mcast_ack_handler, &ret); + nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, mcast_family_handler, &grp); + + while (ret > 0) + nl_recvmsgs(sock, cb); + + if (ret == 0) + ret = grp.id; + nla_put_failure: + nl_cb_put(cb); + out_fail_cb: + nlmsg_free(msg); + return ret; +} + +static int ovpn_listen_mcast(void) +{ + struct nl_sock *sock; + struct nl_cb *cb; + int mcid, ret; + + sock = nl_socket_alloc(); + if (!sock) { + fprintf(stderr, "cannot allocate netlink socket\n"); + goto err_free; + } + + nl_socket_set_buffer_size(sock, 8192, 8192); + + ret = genl_connect(sock); + if (ret < 0) { + fprintf(stderr, "cannot connect to generic netlink: %s\n", + nl_geterror(ret)); + goto err_free; + } + + mcid = ovpn_get_mcast_id(sock, OVPN_FAMILY_NAME, OVPN_MCGRP_PEERS); + if (mcid < 0) { + fprintf(stderr, "cannot get mcast group: %s\n", + nl_geterror(mcid)); + goto err_free; + } + + ret = nl_socket_add_membership(sock, mcid); + if (ret) { + fprintf(stderr, "failed to join mcast group: %d\n", ret); + goto err_free; + } + + ret = 1; + cb = nl_cb_alloc(NL_CB_DEFAULT); + nl_cb_set(cb, NL_CB_SEQ_CHECK, NL_CB_CUSTOM, nl_seq_check, NULL); + nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, ovpn_handle_msg, &ret); + nl_cb_err(cb, NL_CB_CUSTOM, ovpn_nl_cb_error, &ret); + + while (ret == 1) { + int err = nl_recvmsgs(sock, cb); + + if (err < 0) { + fprintf(stderr, + "cannot receive netlink message: (%d) %s\n", + err, nl_geterror(-err)); + ret = -1; + break; + } + } + + nl_cb_put(cb); +err_free: + nl_socket_free(sock); + return ret; +} + +static void usage(const char *cmd) +{ + fprintf(stderr, + "Usage %s <command> <iface> [arguments..]\n", + cmd); + fprintf(stderr, "where <command> can be one of the following\n\n"); + + fprintf(stderr, "* new_iface <iface> [mode]: create new ovpn interface\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tmode:\n"); + fprintf(stderr, "\t\t- P2P for peer-to-peer mode (i.e. client)\n"); + fprintf(stderr, "\t\t- MP for multi-peer mode (i.e. server)\n"); + + fprintf(stderr, "* del_iface <iface>: delete ovpn interface\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + + fprintf(stderr, + "* listen <iface> <lport> <peers_file> [ipv6]: listen for incoming peer TCP connections\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tlport: TCP port to listen to\n"); + fprintf(stderr, + "\tpeers_file: file containing one peer per line: Line format:\n"); + fprintf(stderr, "\t\t<peer_id> <vpnaddr>\n"); + fprintf(stderr, + "\tipv6: whether the socket should listen to the IPv6 wildcard address\n"); + + fprintf(stderr, + "* connect <iface> <peer_id> <raddr> <rport> [key_file]: start connecting peer of TCP-based VPN session\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the connecting peer\n"); + fprintf(stderr, "\traddr: peer IP address to connect to\n"); + fprintf(stderr, "\trport: peer TCP port to connect to\n"); + fprintf(stderr, + "\tkey_file: file containing the symmetric key for encryption\n"); + + fprintf(stderr, + "* new_peer <iface> <peer_id> <lport> <raddr> <rport> [vpnaddr]: add new peer\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tlport: local UDP port to bind to\n"); + fprintf(stderr, + "\tpeer_id: peer ID to be used in data packets to/from this peer\n"); + fprintf(stderr, "\traddr: peer IP address\n"); + fprintf(stderr, "\trport: peer UDP port\n"); + fprintf(stderr, "\tvpnaddr: peer VPN IP\n"); + + fprintf(stderr, + "* new_multi_peer <iface> <lport> <peers_file>: add multiple peers as listed in the file\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tlport: local UDP port to bind to\n"); + fprintf(stderr, + "\tpeers_file: text file containing one peer per line. Line format:\n"); + fprintf(stderr, "\t\t<peer_id> <raddr> <rport> <vpnaddr>\n"); + + fprintf(stderr, + "* set_peer <iface> <peer_id> <keepalive_interval> <keepalive_timeout>: set peer attributes\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n"); + fprintf(stderr, + "\tkeepalive_interval: interval for sending ping messages\n"); + fprintf(stderr, + "\tkeepalive_timeout: time after which a peer is timed out\n"); + + fprintf(stderr, "* del_peer <iface> <peer_id>: delete peer\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to delete\n"); + + fprintf(stderr, "* get_peer <iface> [peer_id]: retrieve peer(s) status\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, + "\tpeer_id: peer ID of the peer to query. All peers are returned if omitted\n"); + + fprintf(stderr, + "* new_key <iface> <peer_id> <slot> <key_id> <cipher> <key_dir> <key_file>: set data channel key\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, + "\tpeer_id: peer ID of the peer to configure the key for\n"); + fprintf(stderr, "\tslot: either 1 (primary) or 2 (secondary)\n"); + fprintf(stderr, "\tkey_id: an ID from 0 to 7\n"); + fprintf(stderr, + "\tcipher: cipher to use, supported: aes (AES-GCM), chachapoly (CHACHA20POLY1305)\n"); + fprintf(stderr, + "\tkey_dir: key direction, must 0 on one host and 1 on the other\n"); + fprintf(stderr, "\tkey_file: file containing the pre-shared key\n"); + + fprintf(stderr, + "* del_key <iface> <peer_id> [slot]: erase existing data channel key\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n"); + fprintf(stderr, "\tslot: slot to erase. PRIMARY if omitted\n"); + + fprintf(stderr, + "* get_key <iface> <peer_id> <slot>: retrieve non sensible key data\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to query\n"); + fprintf(stderr, "\tslot: either 1 (primary) or 2 (secondary)\n"); + + fprintf(stderr, + "* swap_keys <iface> <peer_id>: swap content of primary and secondary key slots\n"); + fprintf(stderr, "\tiface: ovpn interface name\n"); + fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n"); + + fprintf(stderr, + "* listen_mcast: listen to ovpn netlink multicast messages\n"); +} + +static int ovpn_parse_remote(struct ovpn_ctx *ovpn, const char *host, + const char *service, const char *vpnip) +{ + int ret; + struct addrinfo *result; + struct addrinfo hints = { + .ai_family = ovpn->sa_family, + .ai_socktype = SOCK_DGRAM, + .ai_protocol = IPPROTO_UDP + }; + + if (host) { + ret = getaddrinfo(host, service, &hints, &result); + if (ret == EAI_NONAME || ret == EAI_FAIL) + return -1; + + if (!(result->ai_family == AF_INET && + result->ai_addrlen == sizeof(struct sockaddr_in)) && + !(result->ai_family == AF_INET6 && + result->ai_addrlen == sizeof(struct sockaddr_in6))) { + ret = -EINVAL; + goto out; + } + + memcpy(&ovpn->remote, result->ai_addr, result->ai_addrlen); + } + + if (vpnip) { + ret = getaddrinfo(vpnip, NULL, &hints, &result); + if (ret == EAI_NONAME || ret == EAI_FAIL) + return -1; + + if (!(result->ai_family == AF_INET && + result->ai_addrlen == sizeof(struct sockaddr_in)) && + !(result->ai_family == AF_INET6 && + result->ai_addrlen == sizeof(struct sockaddr_in6))) { + ret = -EINVAL; + goto out; + } + + memcpy(&ovpn->peer_ip, result->ai_addr, result->ai_addrlen); + ovpn->sa_family = result->ai_family; + + ovpn->peer_ip_set = true; + } + + ret = 0; +out: + freeaddrinfo(result); + return ret; +} + +static int ovpn_parse_new_peer(struct ovpn_ctx *ovpn, const char *peer_id, + const char *raddr, const char *rport, + const char *vpnip) +{ + ovpn->peer_id = strtoul(peer_id, NULL, 10); + if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + return ovpn_parse_remote(ovpn, raddr, rport, vpnip); +} + +static int ovpn_parse_key_slot(const char *arg, struct ovpn_ctx *ovpn) +{ + int slot = strtoul(arg, NULL, 10); + + if (errno == ERANGE || slot < 1 || slot > 2) { + fprintf(stderr, "key slot out of range\n"); + return -1; + } + + switch (slot) { + case 1: + ovpn->key_slot = OVPN_KEY_SLOT_PRIMARY; + break; + case 2: + ovpn->key_slot = OVPN_KEY_SLOT_SECONDARY; + break; + } + + return 0; +} + +static int ovpn_send_tcp_data(int socket) +{ + uint16_t len = htons(1000); + uint8_t buf[1002]; + int ret; + + memcpy(buf, &len, sizeof(len)); + memset(buf + sizeof(len), 0x86, sizeof(buf) - sizeof(len)); + + ret = send(socket, buf, sizeof(buf), 0); + + fprintf(stdout, "Sent %u bytes over TCP socket\n", ret); + + return ret > 0 ? 0 : ret; +} + +static int ovpn_recv_tcp_data(int socket) +{ + uint8_t buf[1002]; + uint16_t len; + int ret; + + ret = recv(socket, buf, sizeof(buf), 0); + + if (ret < 2) { + fprintf(stderr, ">>>> Error while reading TCP data: %d\n", ret); + return ret; + } + + memcpy(&len, buf, sizeof(len)); + len = ntohs(len); + + fprintf(stdout, ">>>> Received %u bytes over TCP socket, header: %u\n", + ret, len); + +/* int i; + * for (i = 2; i < ret; i++) { + * fprintf(stdout, "0x%.2x ", buf[i]); + * if (i && !((i - 2) % 16)) + * fprintf(stdout, "\n"); + * } + * fprintf(stdout, "\n"); + */ + return 0; +} + +static enum ovpn_cmd ovpn_parse_cmd(const char *cmd) +{ + if (!strcmp(cmd, "new_iface")) + return CMD_NEW_IFACE; + + if (!strcmp(cmd, "del_iface")) + return CMD_DEL_IFACE; + + if (!strcmp(cmd, "listen")) + return CMD_LISTEN; + + if (!strcmp(cmd, "connect")) + return CMD_CONNECT; + + if (!strcmp(cmd, "new_peer")) + return CMD_NEW_PEER; + + if (!strcmp(cmd, "new_multi_peer")) + return CMD_NEW_MULTI_PEER; + + if (!strcmp(cmd, "set_peer")) + return CMD_SET_PEER; + + if (!strcmp(cmd, "del_peer")) + return CMD_DEL_PEER; + + if (!strcmp(cmd, "get_peer")) + return CMD_GET_PEER; + + if (!strcmp(cmd, "new_key")) + return CMD_NEW_KEY; + + if (!strcmp(cmd, "del_key")) + return CMD_DEL_KEY; + + if (!strcmp(cmd, "get_key")) + return CMD_GET_KEY; + + if (!strcmp(cmd, "swap_keys")) + return CMD_SWAP_KEYS; + + if (!strcmp(cmd, "listen_mcast")) + return CMD_LISTEN_MCAST; + + return CMD_INVALID; +} + +static int ovpn_run_cmd(struct ovpn_ctx *ovpn) +{ + char peer_id[10], vpnip[INET6_ADDRSTRLEN], raddr[128], rport[10]; + int n, ret; + FILE *fp; + + switch (ovpn->cmd) { + case CMD_NEW_IFACE: + ret = ovpn_new_iface(ovpn); + break; + case CMD_DEL_IFACE: + ret = ovpn_del_iface(ovpn); + break; + case CMD_LISTEN: + ret = ovpn_listen(ovpn, ovpn->sa_family); + if (ret < 0) { + fprintf(stderr, "cannot listen on TCP socket\n"); + return ret; + } + + fp = fopen(ovpn->peers_file, "r"); + if (!fp) { + fprintf(stderr, "cannot open file: %s\n", + ovpn->peers_file); + return -1; + } + + while ((n = fscanf(fp, "%s %s\n", peer_id, vpnip)) == 2) { + struct ovpn_ctx peer_ctx = { 0 }; + + peer_ctx.ifindex = ovpn->ifindex; + peer_ctx.sa_family = ovpn->sa_family; + + peer_ctx.socket = ovpn_accept(ovpn); + if (peer_ctx.socket < 0) { + fprintf(stderr, "cannot accept connection!\n"); + return -1; + } + + /* store the socket of the first peer to test TCP I/O */ + if (ovpn->cli_socket < 0) + ovpn->cli_socket = peer_ctx.socket; + + ret = ovpn_parse_new_peer(&peer_ctx, peer_id, NULL, + NULL, vpnip); + if (ret < 0) { + fprintf(stderr, "error while parsing line\n"); + return -1; + } + + ret = ovpn_new_peer(&peer_ctx, true); + if (ret < 0) { + fprintf(stderr, + "cannot add peer to VPN: %s %s\n", + peer_id, vpnip); + return ret; + } + } + + if (ovpn->cli_socket >= 0) + ret = ovpn_recv_tcp_data(ovpn->cli_socket); + + break; + case CMD_CONNECT: + ret = ovpn_connect(ovpn); + if (ret < 0) { + fprintf(stderr, "cannot connect TCP socket\n"); + return ret; + } + + ret = ovpn_new_peer(ovpn, true); + if (ret < 0) { + fprintf(stderr, "cannot add peer to VPN\n"); + close(ovpn->socket); + return ret; + } + + if (ovpn->cipher != OVPN_CIPHER_ALG_NONE) { + ret = ovpn_new_key(ovpn); + if (ret < 0) { + fprintf(stderr, "cannot set key\n"); + return ret; + } + } + + ret = ovpn_send_tcp_data(ovpn->socket); + break; + case CMD_NEW_PEER: + ret = ovpn_udp_socket(ovpn, AF_INET6); //ovpn->sa_family ? + if (ret < 0) + return ret; + + ret = ovpn_new_peer(ovpn, false); + break; + case CMD_NEW_MULTI_PEER: + ret = ovpn_udp_socket(ovpn, AF_INET6); + if (ret < 0) + return ret; + + fp = fopen(ovpn->peers_file, "r"); + if (!fp) { + fprintf(stderr, "cannot open file: %s\n", + ovpn->peers_file); + return -1; + } + + while ((n = fscanf(fp, "%s %s %s %s\n", peer_id, raddr, rport, + vpnip)) == 4) { + struct ovpn_ctx peer_ctx = { 0 }; + + peer_ctx.ifindex = ovpn->ifindex; + peer_ctx.socket = ovpn->socket; + peer_ctx.sa_family = AF_UNSPEC; + + ret = ovpn_parse_new_peer(&peer_ctx, peer_id, raddr, + rport, vpnip); + if (ret < 0) { + fprintf(stderr, "error while parsing line\n"); + return -1; + } + + ret = ovpn_new_peer(&peer_ctx, false); + if (ret < 0) { + fprintf(stderr, + "cannot add peer to VPN: %s %s %s %s\n", + peer_id, raddr, rport, vpnip); + return ret; + } + } + break; + case CMD_SET_PEER: + ret = ovpn_set_peer(ovpn); + break; + case CMD_DEL_PEER: + ret = ovpn_del_peer(ovpn); + break; + case CMD_GET_PEER: + if (ovpn->peer_id == PEER_ID_UNDEF) + fprintf(stderr, "List of peers connected to: %s\n", + ovpn->ifname); + + ret = ovpn_get_peer(ovpn); + break; + case CMD_NEW_KEY: + ret = ovpn_new_key(ovpn); + break; + case CMD_DEL_KEY: + ret = ovpn_del_key(ovpn); + break; + case CMD_GET_KEY: + ret = ovpn_get_key(ovpn); + break; + case CMD_SWAP_KEYS: + ret = ovpn_swap_keys(ovpn); + break; + case CMD_LISTEN_MCAST: + ret = ovpn_listen_mcast(); + break; + case CMD_INVALID: + break; + } + + return ret; +} + +static int ovpn_parse_cmd_args(struct ovpn_ctx *ovpn, int argc, char *argv[]) +{ + int ret; + + /* no args required for LISTEN_MCAST */ + if (ovpn->cmd == CMD_LISTEN_MCAST) + return 0; + + /* all commands need an ifname */ + if (argc < 3) + return -EINVAL; + + strscpy(ovpn->ifname, argv[2], IFNAMSIZ - 1); + ovpn->ifname[IFNAMSIZ - 1] = '\0'; + + /* all commands, except NEW_IFNAME, needs an ifindex */ + if (ovpn->cmd != CMD_NEW_IFACE) { + ovpn->ifindex = if_nametoindex(ovpn->ifname); + if (!ovpn->ifindex) { + fprintf(stderr, "cannot find interface: %s\n", + strerror(errno)); + return -1; + } + } + + switch (ovpn->cmd) { + case CMD_NEW_IFACE: + if (argc < 4) + break; + + if (!strcmp(argv[3], "P2P")) { + ovpn->mode = OVPN_MODE_P2P; + } else if (!strcmp(argv[3], "MP")) { + ovpn->mode = OVPN_MODE_MP; + } else { + fprintf(stderr, "Cannot parse iface mode: %s\n", + argv[3]); + return -1; + } + ovpn->mode_set = true; + break; + case CMD_DEL_IFACE: + break; + case CMD_LISTEN: + if (argc < 5) + return -EINVAL; + + ovpn->lport = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->lport > 65535) { + fprintf(stderr, "lport value out of range\n"); + return -1; + } + + ovpn->peers_file = argv[4]; + + if (argc > 5 && !strcmp(argv[5], "ipv6")) + ovpn->sa_family = AF_INET6; + break; + case CMD_CONNECT: + if (argc < 6) + return -EINVAL; + + ovpn->sa_family = AF_INET; + + ret = ovpn_parse_new_peer(ovpn, argv[3], argv[4], argv[5], + NULL); + if (ret < 0) { + fprintf(stderr, "Cannot parse remote peer data\n"); + return -1; + } + + if (argc > 6) { + ovpn->key_slot = OVPN_KEY_SLOT_PRIMARY; + ovpn->key_id = 0; + ovpn->cipher = OVPN_CIPHER_ALG_AES_GCM; + ovpn->key_dir = KEY_DIR_OUT; + + ret = ovpn_parse_key(argv[6], ovpn); + if (ret) + return -1; + } + break; + case CMD_NEW_PEER: + if (argc < 7) + return -EINVAL; + + ovpn->lport = strtoul(argv[4], NULL, 10); + if (errno == ERANGE || ovpn->lport > 65535) { + fprintf(stderr, "lport value out of range\n"); + return -1; + } + + const char *vpnip = (argc > 7) ? argv[7] : NULL; + + ret = ovpn_parse_new_peer(ovpn, argv[3], argv[5], argv[6], + vpnip); + if (ret < 0) + return -1; + break; + case CMD_NEW_MULTI_PEER: + if (argc < 5) + return -EINVAL; + + ovpn->lport = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->lport > 65535) { + fprintf(stderr, "lport value out of range\n"); + return -1; + } + + ovpn->peers_file = argv[4]; + break; + case CMD_SET_PEER: + if (argc < 6) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ovpn->keepalive_interval = strtoul(argv[4], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, + "keepalive interval value out of range\n"); + return -1; + } + + ovpn->keepalive_timeout = strtoul(argv[5], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, + "keepalive interval value out of range\n"); + return -1; + } + break; + case CMD_DEL_PEER: + if (argc < 4) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + break; + case CMD_GET_PEER: + ovpn->peer_id = PEER_ID_UNDEF; + if (argc > 3) { + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + } + break; + case CMD_NEW_KEY: + if (argc < 9) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ret = ovpn_parse_key_slot(argv[4], ovpn); + if (ret) + return -1; + + ovpn->key_id = strtoul(argv[5], NULL, 10); + if (errno == ERANGE || ovpn->key_id > 2) { + fprintf(stderr, "key ID out of range\n"); + return -1; + } + + ret = ovpn_parse_cipher(argv[6], ovpn); + if (ret < 0) + return -1; + + ret = ovpn_parse_key_direction(argv[7], ovpn); + if (ret < 0) + return -1; + + ret = ovpn_parse_key(argv[8], ovpn); + if (ret) + return -1; + break; + case CMD_DEL_KEY: + if (argc < 4) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ret = ovpn_parse_key_slot(argv[4], ovpn); + if (ret) + return ret; + break; + case CMD_GET_KEY: + if (argc < 5) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + + ret = ovpn_parse_key_slot(argv[4], ovpn); + if (ret) + return ret; + break; + case CMD_SWAP_KEYS: + if (argc < 4) + return -EINVAL; + + ovpn->peer_id = strtoul(argv[3], NULL, 10); + if (errno == ERANGE) { + fprintf(stderr, "peer ID value out of range\n"); + return -1; + } + break; + case CMD_LISTEN_MCAST: + break; + case CMD_INVALID: + break; + } + + return 0; +} + +int main(int argc, char *argv[]) +{ + struct ovpn_ctx ovpn; + int ret; + + if (argc < 2) { + usage(argv[0]); + return -1; + } + + memset(&ovpn, 0, sizeof(ovpn)); + ovpn.sa_family = AF_INET; + ovpn.cipher = OVPN_CIPHER_ALG_NONE; + ovpn.cli_socket = -1; + + ovpn.cmd = ovpn_parse_cmd(argv[1]); + if (ovpn.cmd == CMD_INVALID) { + fprintf(stderr, "Error: unknown command.\n\n"); + usage(argv[0]); + return -1; + } + + ret = ovpn_parse_cmd_args(&ovpn, argc, argv); + if (ret < 0) { + fprintf(stderr, "Error: invalid arguments.\n\n"); + if (ret == -EINVAL) + usage(argv[0]); + return ret; + } + + ret = ovpn_run_cmd(&ovpn); + if (ret) + fprintf(stderr, "Cannot execute command: %s (%d)\n", + strerror(-ret), ret); + + return ret; +} diff --git a/tools/testing/selftests/net/ovpn/tcp_peers.txt b/tools/testing/selftests/net/ovpn/tcp_peers.txt new file mode 100644 index 0000000000000000000000000000000000000000..d753eebe8716ed3588334ad766981e883ed2469a --- /dev/null +++ b/tools/testing/selftests/net/ovpn/tcp_peers.txt @@ -0,0 +1,5 @@ +1 5.5.5.2 +2 5.5.5.3 +3 5.5.5.4 +4 5.5.5.5 +5 5.5.5.6 diff --git a/tools/testing/selftests/net/ovpn/test-chachapoly.sh b/tools/testing/selftests/net/ovpn/test-chachapoly.sh new file mode 100755 index 0000000000000000000000000000000000000000..79788f10d33b9682ed27590a48d136eb50b2202c --- /dev/null +++ b/tools/testing/selftests/net/ovpn/test-chachapoly.sh @@ -0,0 +1,9 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +ALG="chachapoly" + +source test.sh diff --git a/tools/testing/selftests/net/ovpn/test-float.sh b/tools/testing/selftests/net/ovpn/test-float.sh new file mode 100755 index 0000000000000000000000000000000000000000..93e1b729861d6b3f9f3f2e19d84e524c293ee3cf --- /dev/null +++ b/tools/testing/selftests/net/ovpn/test-float.sh @@ -0,0 +1,9 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +FLOAT="1" + +source test.sh diff --git a/tools/testing/selftests/net/ovpn/test-tcp.sh b/tools/testing/selftests/net/ovpn/test-tcp.sh new file mode 100755 index 0000000000000000000000000000000000000000..7542f595cc5696396513ed029cb96fe3b922d0e4 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/test-tcp.sh @@ -0,0 +1,9 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +PROTO="TCP" + +source test.sh diff --git a/tools/testing/selftests/net/ovpn/test.sh b/tools/testing/selftests/net/ovpn/test.sh new file mode 100755 index 0000000000000000000000000000000000000000..fd5a35b5bac0c021e0e17bddf4ed3bec6ef3a384 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/test.sh @@ -0,0 +1,182 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020-2024 OpenVPN, Inc. +# +# Author: Antonio Quartulli antonio@openvpn.net + +#set -x +set -e + +UDP_PEERS_FILE=${UDP_PEERS_FILE:-udp_peers.txt} +TCP_PEERS_FILE=${TCP_PEERS_FILE:-tcp_peers.txt} +OVPN_CLI=${OVPN_CLI:-./ovpn-cli} +ALG=${ALG:-aes} +PROTO=${PROTO:-UDP} +FLOAT=${FLOAT:-0} + +create_ns() { + ip netns add peer${1} +} + +setup_ns() { + MODE="P2P" + + if [ ${1} -eq 0 ]; then + MODE="MP" + for p in $(seq 1 ${NUM_PEERS}); do + ip link add veth${p} netns peer0 type veth peer name veth${p} netns peer${p} + + ip -n peer0 addr add 10.10.${p}.1/24 dev veth${p} + ip -n peer0 link set veth${p} up + + ip -n peer${p} addr add 10.10.${p}.2/24 dev veth${p} + ip -n peer${p} link set veth${p} up + done + fi + + ip netns exec peer${1} ${OVPN_CLI} new_iface tun${1} $MODE + ip -n peer${1} addr add ${2} dev tun${1} + ip -n peer${1} link set tun${1} up +} + +add_peer() { + if [ "${PROTO}" == "UDP" ]; then + if [ ${1} -eq 0 ]; then + ip netns exec peer0 ${OVPN_CLI} new_multi_peer tun0 1 ${UDP_PEERS_FILE} + + for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 1 0 ${ALG} 0 \ + data64.key + done + else + ip netns exec peer${1} ${OVPN_CLI} new_peer tun${1} ${1} 1 10.10.${1}.1 1 + ip netns exec peer${1} ${OVPN_CLI} new_key tun${1} ${1} 1 0 ${ALG} 1 \ + data64.key + fi + else + if [ ${1} -eq 0 ]; then + (ip netns exec peer0 ${OVPN_CLI} listen tun0 1 ${TCP_PEERS_FILE} && { + for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 1 0 \ + ${ALG} 0 data64.key + done + }) & + sleep 5 + else + ip netns exec peer${1} ${OVPN_CLI} connect tun${1} ${1} 10.10.${1}.1 1 \ + data64.key + fi + fi +} + +cleanup() { + # first test peers disconnect on down event + for p in $(seq 0 10); do + ip -n peer${p} link set tun${p} down 2>/dev/null || true + done + for p in $(seq 1 10); do + ip -n peer0 link del veth${p} 2>/dev/null || true + done + for p in $(seq 0 10); do + ip netns exec peer${p} ${OVPN_CLI} del_iface tun${p} 2>/dev/null || true + ip netns del peer${p} 2>/dev/null || true + done +} + +if [ "${PROTO}" == "UDP" ]; then + NUM_PEERS=${NUM_PEERS:-$(wc -l ${UDP_PEERS_FILE} | awk '{print $1}')} +else + NUM_PEERS=${NUM_PEERS:-$(wc -l ${TCP_PEERS_FILE} | awk '{print $1}')} +fi + +cleanup + +modprobe -q ovpn || true + +for p in $(seq 0 ${NUM_PEERS}); do + create_ns ${p} +done + +for p in $(seq 0 ${NUM_PEERS}); do + setup_ns ${p} 5.5.5.$((${p} + 1))/24 +done + +for p in $(seq 0 ${NUM_PEERS}); do + add_peer ${p} +done + +for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} set_peer tun0 ${p} 60 120 + ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 60 120 +done + +for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ping -qfc 1000 -w 5 5.5.5.$((${p} + 1)) +done + +if [ "$FLOAT" == "1" ]; then + # make clients float.. + for p in $(seq 1 ${NUM_PEERS}); do + ip -n peer${p} addr del 10.10.${p}.2/24 dev veth${p} + ip -n peer${p} addr add 10.10.${p}.3/24 dev veth${p} + done + for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer${p} ping -qfc 1000 -w 5 5.5.5.1 + done +fi + +ip netns exec peer0 iperf3 -1 -s & +sleep 1 +ip netns exec peer1 iperf3 -Z -t 3 -c 5.5.5.1 + +echo "Adding secondary key and then swap:" +for p in $(seq 1 ${NUM_PEERS}); do + ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 2 1 ${ALG} 0 data64.key + ip netns exec peer${p} ${OVPN_CLI} new_key tun${p} ${p} 2 1 ${ALG} 1 data64.key + ip netns exec peer${p} ${OVPN_CLI} swap_keys tun${p} ${p} +done + +sleep 1 +echo "Querying all peers:" +ip netns exec peer0 ${OVPN_CLI} get_peer tun0 +ip netns exec peer1 ${OVPN_CLI} get_peer tun1 + +echo "Querying peer 1:" +ip netns exec peer0 ${OVPN_CLI} get_peer tun0 1 + +echo "Querying non-existent peer 10:" +ip netns exec peer0 ${OVPN_CLI} get_peer tun0 10 || true + +echo "Deleting peer 1:" +ip netns exec peer0 ${OVPN_CLI} del_peer tun0 1 +ip netns exec peer1 ${OVPN_CLI} del_peer tun1 1 + +echo "Querying keys:" +for p in $(seq 2 ${NUM_PEERS}); do + ip netns exec peer${p} ${OVPN_CLI} get_key tun${p} ${p} 1 + ip netns exec peer${p} ${OVPN_CLI} get_key tun${p} ${p} 2 +done + +echo "Deleting keys:" +for p in $(seq 2 ${NUM_PEERS}); do + ip netns exec peer${p} ${OVPN_CLI} del_key tun${p} ${p} 1 + ip netns exec peer${p} ${OVPN_CLI} del_key tun${p} ${p} 2 +done + +echo "Setting timeout to 10s MP:" +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 2 ${NUM_PEERS}); do + ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 10 10 +done +sleep 15 + +cleanup + +modprobe -r ovpn || true diff --git a/tools/testing/selftests/net/ovpn/udp_peers.txt b/tools/testing/selftests/net/ovpn/udp_peers.txt new file mode 100644 index 0000000000000000000000000000000000000000..32f14bd9347a63e58438311b6d880b9fef768aa2 --- /dev/null +++ b/tools/testing/selftests/net/ovpn/udp_peers.txt @@ -0,0 +1,5 @@ +1 10.10.1.2 1 5.5.5.2 +2 10.10.2.2 1 5.5.5.3 +3 10.10.3.2 1 5.5.5.4 +4 10.10.4.2 1 5.5.5.5 +5 10.10.5.2 1 5.5.5.6