Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
4 */
5
6#include "queueing.h"
7#include "socket.h"
8#include "timers.h"
9#include "device.h"
10#include "ratelimiter.h"
11#include "peer.h"
12#include "messages.h"
13
14#include <linux/module.h>
15#include <linux/rtnetlink.h>
16#include <linux/inet.h>
17#include <linux/netdevice.h>
18#include <linux/inetdevice.h>
19#include <linux/if_arp.h>
20#include <linux/icmp.h>
21#include <linux/suspend.h>
22#include <net/dst_metadata.h>
23#include <net/gso.h>
24#include <net/icmp.h>
25#include <net/rtnetlink.h>
26#include <net/ip_tunnels.h>
27#include <net/addrconf.h>
28
29static LIST_HEAD(device_list);
30
31static int wg_open(struct net_device *dev)
32{
33 struct in_device *dev_v4 = __in_dev_get_rtnl(dev);
34 struct inet6_dev *dev_v6 = __in6_dev_get(dev);
35 struct wg_device *wg = netdev_priv(dev);
36 struct wg_peer *peer;
37 int ret;
38
39 if (dev_v4) {
40 /* At some point we might put this check near the ip_rt_send_
41 * redirect call of ip_forward in net/ipv4/ip_forward.c, similar
42 * to the current secpath check.
43 */
44 IN_DEV_CONF_SET(dev_v4, SEND_REDIRECTS, false);
45 IPV4_DEVCONF_ALL(dev_net(dev), SEND_REDIRECTS) = false;
46 }
47 if (dev_v6)
48 dev_v6->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_NONE;
49
50 mutex_lock(&wg->device_update_lock);
51 ret = wg_socket_init(wg, wg->incoming_port);
52 if (ret < 0)
53 goto out;
54 list_for_each_entry(peer, &wg->peer_list, peer_list) {
55 wg_packet_send_staged_packets(peer);
56 if (peer->persistent_keepalive_interval)
57 wg_packet_send_keepalive(peer);
58 }
59out:
60 mutex_unlock(&wg->device_update_lock);
61 return ret;
62}
63
64static int wg_pm_notification(struct notifier_block *nb, unsigned long action, void *data)
65{
66 struct wg_device *wg;
67 struct wg_peer *peer;
68
69 /* If the machine is constantly suspending and resuming, as part of
70 * its normal operation rather than as a somewhat rare event, then we
71 * don't actually want to clear keys.
72 */
73 if (IS_ENABLED(CONFIG_PM_AUTOSLEEP) ||
74 IS_ENABLED(CONFIG_PM_USERSPACE_AUTOSLEEP))
75 return 0;
76
77 if (action != PM_HIBERNATION_PREPARE && action != PM_SUSPEND_PREPARE)
78 return 0;
79
80 rtnl_lock();
81 list_for_each_entry(wg, &device_list, device_list) {
82 mutex_lock(&wg->device_update_lock);
83 list_for_each_entry(peer, &wg->peer_list, peer_list) {
84 del_timer(&peer->timer_zero_key_material);
85 wg_noise_handshake_clear(&peer->handshake);
86 wg_noise_keypairs_clear(&peer->keypairs);
87 }
88 mutex_unlock(&wg->device_update_lock);
89 }
90 rtnl_unlock();
91 rcu_barrier();
92 return 0;
93}
94
95static struct notifier_block pm_notifier = { .notifier_call = wg_pm_notification };
96
97static int wg_vm_notification(struct notifier_block *nb, unsigned long action, void *data)
98{
99 struct wg_device *wg;
100 struct wg_peer *peer;
101
102 rtnl_lock();
103 list_for_each_entry(wg, &device_list, device_list) {
104 mutex_lock(&wg->device_update_lock);
105 list_for_each_entry(peer, &wg->peer_list, peer_list)
106 wg_noise_expire_current_peer_keypairs(peer);
107 mutex_unlock(&wg->device_update_lock);
108 }
109 rtnl_unlock();
110 return 0;
111}
112
113static struct notifier_block vm_notifier = { .notifier_call = wg_vm_notification };
114
115static int wg_stop(struct net_device *dev)
116{
117 struct wg_device *wg = netdev_priv(dev);
118 struct wg_peer *peer;
119 struct sk_buff *skb;
120
121 mutex_lock(&wg->device_update_lock);
122 list_for_each_entry(peer, &wg->peer_list, peer_list) {
123 wg_packet_purge_staged_packets(peer);
124 wg_timers_stop(peer);
125 wg_noise_handshake_clear(&peer->handshake);
126 wg_noise_keypairs_clear(&peer->keypairs);
127 wg_noise_reset_last_sent_handshake(&peer->last_sent_handshake);
128 }
129 mutex_unlock(&wg->device_update_lock);
130 while ((skb = ptr_ring_consume(&wg->handshake_queue.ring)) != NULL)
131 kfree_skb(skb);
132 atomic_set(&wg->handshake_queue_len, 0);
133 wg_socket_reinit(wg, NULL, NULL);
134 return 0;
135}
136
137static netdev_tx_t wg_xmit(struct sk_buff *skb, struct net_device *dev)
138{
139 struct wg_device *wg = netdev_priv(dev);
140 struct sk_buff_head packets;
141 struct wg_peer *peer;
142 struct sk_buff *next;
143 sa_family_t family;
144 u32 mtu;
145 int ret;
146
147 if (unlikely(!wg_check_packet_protocol(skb))) {
148 ret = -EPROTONOSUPPORT;
149 net_dbg_ratelimited("%s: Invalid IP packet\n", dev->name);
150 goto err;
151 }
152
153 peer = wg_allowedips_lookup_dst(&wg->peer_allowedips, skb);
154 if (unlikely(!peer)) {
155 ret = -ENOKEY;
156 if (skb->protocol == htons(ETH_P_IP))
157 net_dbg_ratelimited("%s: No peer has allowed IPs matching %pI4\n",
158 dev->name, &ip_hdr(skb)->daddr);
159 else if (skb->protocol == htons(ETH_P_IPV6))
160 net_dbg_ratelimited("%s: No peer has allowed IPs matching %pI6\n",
161 dev->name, &ipv6_hdr(skb)->daddr);
162 goto err_icmp;
163 }
164
165 family = READ_ONCE(peer->endpoint.addr.sa_family);
166 if (unlikely(family != AF_INET && family != AF_INET6)) {
167 ret = -EDESTADDRREQ;
168 net_dbg_ratelimited("%s: No valid endpoint has been configured or discovered for peer %llu\n",
169 dev->name, peer->internal_id);
170 goto err_peer;
171 }
172
173 mtu = skb_valid_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
174
175 __skb_queue_head_init(&packets);
176 if (!skb_is_gso(skb)) {
177 skb_mark_not_on_list(skb);
178 } else {
179 struct sk_buff *segs = skb_gso_segment(skb, 0);
180
181 if (IS_ERR(segs)) {
182 ret = PTR_ERR(segs);
183 goto err_peer;
184 }
185 dev_kfree_skb(skb);
186 skb = segs;
187 }
188
189 skb_list_walk_safe(skb, skb, next) {
190 skb_mark_not_on_list(skb);
191
192 skb = skb_share_check(skb, GFP_ATOMIC);
193 if (unlikely(!skb))
194 continue;
195
196 /* We only need to keep the original dst around for icmp,
197 * so at this point we're in a position to drop it.
198 */
199 skb_dst_drop(skb);
200
201 PACKET_CB(skb)->mtu = mtu;
202
203 __skb_queue_tail(&packets, skb);
204 }
205
206 spin_lock_bh(&peer->staged_packet_queue.lock);
207 /* If the queue is getting too big, we start removing the oldest packets
208 * until it's small again. We do this before adding the new packet, so
209 * we don't remove GSO segments that are in excess.
210 */
211 while (skb_queue_len(&peer->staged_packet_queue) > MAX_STAGED_PACKETS) {
212 dev_kfree_skb(__skb_dequeue(&peer->staged_packet_queue));
213 DEV_STATS_INC(dev, tx_dropped);
214 }
215 skb_queue_splice_tail(&packets, &peer->staged_packet_queue);
216 spin_unlock_bh(&peer->staged_packet_queue.lock);
217
218 wg_packet_send_staged_packets(peer);
219
220 wg_peer_put(peer);
221 return NETDEV_TX_OK;
222
223err_peer:
224 wg_peer_put(peer);
225err_icmp:
226 if (skb->protocol == htons(ETH_P_IP))
227 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
228 else if (skb->protocol == htons(ETH_P_IPV6))
229 icmpv6_ndo_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
230err:
231 DEV_STATS_INC(dev, tx_errors);
232 kfree_skb(skb);
233 return ret;
234}
235
236static const struct net_device_ops netdev_ops = {
237 .ndo_open = wg_open,
238 .ndo_stop = wg_stop,
239 .ndo_start_xmit = wg_xmit,
240 .ndo_get_stats64 = dev_get_tstats64
241};
242
243static void wg_destruct(struct net_device *dev)
244{
245 struct wg_device *wg = netdev_priv(dev);
246
247 rtnl_lock();
248 list_del(&wg->device_list);
249 rtnl_unlock();
250 mutex_lock(&wg->device_update_lock);
251 rcu_assign_pointer(wg->creating_net, NULL);
252 wg->incoming_port = 0;
253 wg_socket_reinit(wg, NULL, NULL);
254 /* The final references are cleared in the below calls to destroy_workqueue. */
255 wg_peer_remove_all(wg);
256 destroy_workqueue(wg->handshake_receive_wq);
257 destroy_workqueue(wg->handshake_send_wq);
258 destroy_workqueue(wg->packet_crypt_wq);
259 wg_packet_queue_free(&wg->handshake_queue, true);
260 wg_packet_queue_free(&wg->decrypt_queue, false);
261 wg_packet_queue_free(&wg->encrypt_queue, false);
262 rcu_barrier(); /* Wait for all the peers to be actually freed. */
263 wg_ratelimiter_uninit();
264 memzero_explicit(&wg->static_identity, sizeof(wg->static_identity));
265 free_percpu(dev->tstats);
266 kvfree(wg->index_hashtable);
267 kvfree(wg->peer_hashtable);
268 mutex_unlock(&wg->device_update_lock);
269
270 pr_debug("%s: Interface destroyed\n", dev->name);
271 free_netdev(dev);
272}
273
274static const struct device_type device_type = { .name = KBUILD_MODNAME };
275
276static void wg_setup(struct net_device *dev)
277{
278 struct wg_device *wg = netdev_priv(dev);
279 enum { WG_NETDEV_FEATURES = NETIF_F_HW_CSUM | NETIF_F_RXCSUM |
280 NETIF_F_SG | NETIF_F_GSO |
281 NETIF_F_GSO_SOFTWARE | NETIF_F_HIGHDMA };
282 const int overhead = MESSAGE_MINIMUM_LENGTH + sizeof(struct udphdr) +
283 max(sizeof(struct ipv6hdr), sizeof(struct iphdr));
284
285 dev->netdev_ops = &netdev_ops;
286 dev->header_ops = &ip_tunnel_header_ops;
287 dev->hard_header_len = 0;
288 dev->addr_len = 0;
289 dev->needed_headroom = DATA_PACKET_HEAD_ROOM;
290 dev->needed_tailroom = noise_encrypted_len(MESSAGE_PADDING_MULTIPLE);
291 dev->type = ARPHRD_NONE;
292 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
293 dev->priv_flags |= IFF_NO_QUEUE;
294 dev->features |= NETIF_F_LLTX;
295 dev->features |= WG_NETDEV_FEATURES;
296 dev->hw_features |= WG_NETDEV_FEATURES;
297 dev->hw_enc_features |= WG_NETDEV_FEATURES;
298 dev->mtu = ETH_DATA_LEN - overhead;
299 dev->max_mtu = round_down(INT_MAX, MESSAGE_PADDING_MULTIPLE) - overhead;
300
301 SET_NETDEV_DEVTYPE(dev, &device_type);
302
303 /* We need to keep the dst around in case of icmp replies. */
304 netif_keep_dst(dev);
305
306 memset(wg, 0, sizeof(*wg));
307 wg->dev = dev;
308}
309
310static int wg_newlink(struct net *src_net, struct net_device *dev,
311 struct nlattr *tb[], struct nlattr *data[],
312 struct netlink_ext_ack *extack)
313{
314 struct wg_device *wg = netdev_priv(dev);
315 int ret = -ENOMEM;
316
317 rcu_assign_pointer(wg->creating_net, src_net);
318 init_rwsem(&wg->static_identity.lock);
319 mutex_init(&wg->socket_update_lock);
320 mutex_init(&wg->device_update_lock);
321 wg_allowedips_init(&wg->peer_allowedips);
322 wg_cookie_checker_init(&wg->cookie_checker, wg);
323 INIT_LIST_HEAD(&wg->peer_list);
324 wg->device_update_gen = 1;
325
326 wg->peer_hashtable = wg_pubkey_hashtable_alloc();
327 if (!wg->peer_hashtable)
328 return ret;
329
330 wg->index_hashtable = wg_index_hashtable_alloc();
331 if (!wg->index_hashtable)
332 goto err_free_peer_hashtable;
333
334 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
335 if (!dev->tstats)
336 goto err_free_index_hashtable;
337
338 wg->handshake_receive_wq = alloc_workqueue("wg-kex-%s",
339 WQ_CPU_INTENSIVE | WQ_FREEZABLE, 0, dev->name);
340 if (!wg->handshake_receive_wq)
341 goto err_free_tstats;
342
343 wg->handshake_send_wq = alloc_workqueue("wg-kex-%s",
344 WQ_UNBOUND | WQ_FREEZABLE, 0, dev->name);
345 if (!wg->handshake_send_wq)
346 goto err_destroy_handshake_receive;
347
348 wg->packet_crypt_wq = alloc_workqueue("wg-crypt-%s",
349 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 0, dev->name);
350 if (!wg->packet_crypt_wq)
351 goto err_destroy_handshake_send;
352
353 ret = wg_packet_queue_init(&wg->encrypt_queue, wg_packet_encrypt_worker,
354 MAX_QUEUED_PACKETS);
355 if (ret < 0)
356 goto err_destroy_packet_crypt;
357
358 ret = wg_packet_queue_init(&wg->decrypt_queue, wg_packet_decrypt_worker,
359 MAX_QUEUED_PACKETS);
360 if (ret < 0)
361 goto err_free_encrypt_queue;
362
363 ret = wg_packet_queue_init(&wg->handshake_queue, wg_packet_handshake_receive_worker,
364 MAX_QUEUED_INCOMING_HANDSHAKES);
365 if (ret < 0)
366 goto err_free_decrypt_queue;
367
368 ret = wg_ratelimiter_init();
369 if (ret < 0)
370 goto err_free_handshake_queue;
371
372 ret = register_netdevice(dev);
373 if (ret < 0)
374 goto err_uninit_ratelimiter;
375
376 list_add(&wg->device_list, &device_list);
377
378 /* We wait until the end to assign priv_destructor, so that
379 * register_netdevice doesn't call it for us if it fails.
380 */
381 dev->priv_destructor = wg_destruct;
382
383 pr_debug("%s: Interface created\n", dev->name);
384 return ret;
385
386err_uninit_ratelimiter:
387 wg_ratelimiter_uninit();
388err_free_handshake_queue:
389 wg_packet_queue_free(&wg->handshake_queue, false);
390err_free_decrypt_queue:
391 wg_packet_queue_free(&wg->decrypt_queue, false);
392err_free_encrypt_queue:
393 wg_packet_queue_free(&wg->encrypt_queue, false);
394err_destroy_packet_crypt:
395 destroy_workqueue(wg->packet_crypt_wq);
396err_destroy_handshake_send:
397 destroy_workqueue(wg->handshake_send_wq);
398err_destroy_handshake_receive:
399 destroy_workqueue(wg->handshake_receive_wq);
400err_free_tstats:
401 free_percpu(dev->tstats);
402err_free_index_hashtable:
403 kvfree(wg->index_hashtable);
404err_free_peer_hashtable:
405 kvfree(wg->peer_hashtable);
406 return ret;
407}
408
409static struct rtnl_link_ops link_ops __read_mostly = {
410 .kind = KBUILD_MODNAME,
411 .priv_size = sizeof(struct wg_device),
412 .setup = wg_setup,
413 .newlink = wg_newlink,
414};
415
416static void wg_netns_pre_exit(struct net *net)
417{
418 struct wg_device *wg;
419 struct wg_peer *peer;
420
421 rtnl_lock();
422 list_for_each_entry(wg, &device_list, device_list) {
423 if (rcu_access_pointer(wg->creating_net) == net) {
424 pr_debug("%s: Creating namespace exiting\n", wg->dev->name);
425 netif_carrier_off(wg->dev);
426 mutex_lock(&wg->device_update_lock);
427 rcu_assign_pointer(wg->creating_net, NULL);
428 wg_socket_reinit(wg, NULL, NULL);
429 list_for_each_entry(peer, &wg->peer_list, peer_list)
430 wg_socket_clear_peer_endpoint_src(peer);
431 mutex_unlock(&wg->device_update_lock);
432 }
433 }
434 rtnl_unlock();
435}
436
437static struct pernet_operations pernet_ops = {
438 .pre_exit = wg_netns_pre_exit
439};
440
441int __init wg_device_init(void)
442{
443 int ret;
444
445 ret = register_pm_notifier(&pm_notifier);
446 if (ret)
447 return ret;
448
449 ret = register_random_vmfork_notifier(&vm_notifier);
450 if (ret)
451 goto error_pm;
452
453 ret = register_pernet_device(&pernet_ops);
454 if (ret)
455 goto error_vm;
456
457 ret = rtnl_link_register(&link_ops);
458 if (ret)
459 goto error_pernet;
460
461 return 0;
462
463error_pernet:
464 unregister_pernet_device(&pernet_ops);
465error_vm:
466 unregister_random_vmfork_notifier(&vm_notifier);
467error_pm:
468 unregister_pm_notifier(&pm_notifier);
469 return ret;
470}
471
472void wg_device_uninit(void)
473{
474 rtnl_link_unregister(&link_ops);
475 unregister_pernet_device(&pernet_ops);
476 unregister_random_vmfork_notifier(&vm_notifier);
477 unregister_pm_notifier(&pm_notifier);
478 rcu_barrier();
479}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
4 */
5
6#include "queueing.h"
7#include "socket.h"
8#include "timers.h"
9#include "device.h"
10#include "ratelimiter.h"
11#include "peer.h"
12#include "messages.h"
13
14#include <linux/module.h>
15#include <linux/rtnetlink.h>
16#include <linux/inet.h>
17#include <linux/netdevice.h>
18#include <linux/inetdevice.h>
19#include <linux/if_arp.h>
20#include <linux/icmp.h>
21#include <linux/suspend.h>
22#include <net/icmp.h>
23#include <net/rtnetlink.h>
24#include <net/ip_tunnels.h>
25#include <net/addrconf.h>
26
27static LIST_HEAD(device_list);
28
29static int wg_open(struct net_device *dev)
30{
31 struct in_device *dev_v4 = __in_dev_get_rtnl(dev);
32 struct inet6_dev *dev_v6 = __in6_dev_get(dev);
33 struct wg_device *wg = netdev_priv(dev);
34 struct wg_peer *peer;
35 int ret;
36
37 if (dev_v4) {
38 /* At some point we might put this check near the ip_rt_send_
39 * redirect call of ip_forward in net/ipv4/ip_forward.c, similar
40 * to the current secpath check.
41 */
42 IN_DEV_CONF_SET(dev_v4, SEND_REDIRECTS, false);
43 IPV4_DEVCONF_ALL(dev_net(dev), SEND_REDIRECTS) = false;
44 }
45 if (dev_v6)
46 dev_v6->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_NONE;
47
48 mutex_lock(&wg->device_update_lock);
49 ret = wg_socket_init(wg, wg->incoming_port);
50 if (ret < 0)
51 goto out;
52 list_for_each_entry(peer, &wg->peer_list, peer_list) {
53 wg_packet_send_staged_packets(peer);
54 if (peer->persistent_keepalive_interval)
55 wg_packet_send_keepalive(peer);
56 }
57out:
58 mutex_unlock(&wg->device_update_lock);
59 return ret;
60}
61
62#ifdef CONFIG_PM_SLEEP
63static int wg_pm_notification(struct notifier_block *nb, unsigned long action,
64 void *data)
65{
66 struct wg_device *wg;
67 struct wg_peer *peer;
68
69 /* If the machine is constantly suspending and resuming, as part of
70 * its normal operation rather than as a somewhat rare event, then we
71 * don't actually want to clear keys.
72 */
73 if (IS_ENABLED(CONFIG_PM_AUTOSLEEP) || IS_ENABLED(CONFIG_ANDROID))
74 return 0;
75
76 if (action != PM_HIBERNATION_PREPARE && action != PM_SUSPEND_PREPARE)
77 return 0;
78
79 rtnl_lock();
80 list_for_each_entry(wg, &device_list, device_list) {
81 mutex_lock(&wg->device_update_lock);
82 list_for_each_entry(peer, &wg->peer_list, peer_list) {
83 del_timer(&peer->timer_zero_key_material);
84 wg_noise_handshake_clear(&peer->handshake);
85 wg_noise_keypairs_clear(&peer->keypairs);
86 }
87 mutex_unlock(&wg->device_update_lock);
88 }
89 rtnl_unlock();
90 rcu_barrier();
91 return 0;
92}
93
94static struct notifier_block pm_notifier = { .notifier_call = wg_pm_notification };
95#endif
96
97static int wg_stop(struct net_device *dev)
98{
99 struct wg_device *wg = netdev_priv(dev);
100 struct wg_peer *peer;
101
102 mutex_lock(&wg->device_update_lock);
103 list_for_each_entry(peer, &wg->peer_list, peer_list) {
104 wg_packet_purge_staged_packets(peer);
105 wg_timers_stop(peer);
106 wg_noise_handshake_clear(&peer->handshake);
107 wg_noise_keypairs_clear(&peer->keypairs);
108 wg_noise_reset_last_sent_handshake(&peer->last_sent_handshake);
109 }
110 mutex_unlock(&wg->device_update_lock);
111 skb_queue_purge(&wg->incoming_handshakes);
112 wg_socket_reinit(wg, NULL, NULL);
113 return 0;
114}
115
116static netdev_tx_t wg_xmit(struct sk_buff *skb, struct net_device *dev)
117{
118 struct wg_device *wg = netdev_priv(dev);
119 struct sk_buff_head packets;
120 struct wg_peer *peer;
121 struct sk_buff *next;
122 sa_family_t family;
123 u32 mtu;
124 int ret;
125
126 if (unlikely(!wg_check_packet_protocol(skb))) {
127 ret = -EPROTONOSUPPORT;
128 net_dbg_ratelimited("%s: Invalid IP packet\n", dev->name);
129 goto err;
130 }
131
132 peer = wg_allowedips_lookup_dst(&wg->peer_allowedips, skb);
133 if (unlikely(!peer)) {
134 ret = -ENOKEY;
135 if (skb->protocol == htons(ETH_P_IP))
136 net_dbg_ratelimited("%s: No peer has allowed IPs matching %pI4\n",
137 dev->name, &ip_hdr(skb)->daddr);
138 else if (skb->protocol == htons(ETH_P_IPV6))
139 net_dbg_ratelimited("%s: No peer has allowed IPs matching %pI6\n",
140 dev->name, &ipv6_hdr(skb)->daddr);
141 goto err_icmp;
142 }
143
144 family = READ_ONCE(peer->endpoint.addr.sa_family);
145 if (unlikely(family != AF_INET && family != AF_INET6)) {
146 ret = -EDESTADDRREQ;
147 net_dbg_ratelimited("%s: No valid endpoint has been configured or discovered for peer %llu\n",
148 dev->name, peer->internal_id);
149 goto err_peer;
150 }
151
152 mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
153
154 __skb_queue_head_init(&packets);
155 if (!skb_is_gso(skb)) {
156 skb_mark_not_on_list(skb);
157 } else {
158 struct sk_buff *segs = skb_gso_segment(skb, 0);
159
160 if (IS_ERR(segs)) {
161 ret = PTR_ERR(segs);
162 goto err_peer;
163 }
164 dev_kfree_skb(skb);
165 skb = segs;
166 }
167
168 skb_list_walk_safe(skb, skb, next) {
169 skb_mark_not_on_list(skb);
170
171 skb = skb_share_check(skb, GFP_ATOMIC);
172 if (unlikely(!skb))
173 continue;
174
175 /* We only need to keep the original dst around for icmp,
176 * so at this point we're in a position to drop it.
177 */
178 skb_dst_drop(skb);
179
180 PACKET_CB(skb)->mtu = mtu;
181
182 __skb_queue_tail(&packets, skb);
183 }
184
185 spin_lock_bh(&peer->staged_packet_queue.lock);
186 /* If the queue is getting too big, we start removing the oldest packets
187 * until it's small again. We do this before adding the new packet, so
188 * we don't remove GSO segments that are in excess.
189 */
190 while (skb_queue_len(&peer->staged_packet_queue) > MAX_STAGED_PACKETS) {
191 dev_kfree_skb(__skb_dequeue(&peer->staged_packet_queue));
192 ++dev->stats.tx_dropped;
193 }
194 skb_queue_splice_tail(&packets, &peer->staged_packet_queue);
195 spin_unlock_bh(&peer->staged_packet_queue.lock);
196
197 wg_packet_send_staged_packets(peer);
198
199 wg_peer_put(peer);
200 return NETDEV_TX_OK;
201
202err_peer:
203 wg_peer_put(peer);
204err_icmp:
205 if (skb->protocol == htons(ETH_P_IP))
206 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
207 else if (skb->protocol == htons(ETH_P_IPV6))
208 icmpv6_ndo_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
209err:
210 ++dev->stats.tx_errors;
211 kfree_skb(skb);
212 return ret;
213}
214
215static const struct net_device_ops netdev_ops = {
216 .ndo_open = wg_open,
217 .ndo_stop = wg_stop,
218 .ndo_start_xmit = wg_xmit,
219 .ndo_get_stats64 = dev_get_tstats64
220};
221
222static void wg_destruct(struct net_device *dev)
223{
224 struct wg_device *wg = netdev_priv(dev);
225
226 rtnl_lock();
227 list_del(&wg->device_list);
228 rtnl_unlock();
229 mutex_lock(&wg->device_update_lock);
230 rcu_assign_pointer(wg->creating_net, NULL);
231 wg->incoming_port = 0;
232 wg_socket_reinit(wg, NULL, NULL);
233 /* The final references are cleared in the below calls to destroy_workqueue. */
234 wg_peer_remove_all(wg);
235 destroy_workqueue(wg->handshake_receive_wq);
236 destroy_workqueue(wg->handshake_send_wq);
237 destroy_workqueue(wg->packet_crypt_wq);
238 wg_packet_queue_free(&wg->decrypt_queue);
239 wg_packet_queue_free(&wg->encrypt_queue);
240 rcu_barrier(); /* Wait for all the peers to be actually freed. */
241 wg_ratelimiter_uninit();
242 memzero_explicit(&wg->static_identity, sizeof(wg->static_identity));
243 skb_queue_purge(&wg->incoming_handshakes);
244 free_percpu(dev->tstats);
245 free_percpu(wg->incoming_handshakes_worker);
246 kvfree(wg->index_hashtable);
247 kvfree(wg->peer_hashtable);
248 mutex_unlock(&wg->device_update_lock);
249
250 pr_debug("%s: Interface destroyed\n", dev->name);
251 free_netdev(dev);
252}
253
254static const struct device_type device_type = { .name = KBUILD_MODNAME };
255
256static void wg_setup(struct net_device *dev)
257{
258 struct wg_device *wg = netdev_priv(dev);
259 enum { WG_NETDEV_FEATURES = NETIF_F_HW_CSUM | NETIF_F_RXCSUM |
260 NETIF_F_SG | NETIF_F_GSO |
261 NETIF_F_GSO_SOFTWARE | NETIF_F_HIGHDMA };
262 const int overhead = MESSAGE_MINIMUM_LENGTH + sizeof(struct udphdr) +
263 max(sizeof(struct ipv6hdr), sizeof(struct iphdr));
264
265 dev->netdev_ops = &netdev_ops;
266 dev->header_ops = &ip_tunnel_header_ops;
267 dev->hard_header_len = 0;
268 dev->addr_len = 0;
269 dev->needed_headroom = DATA_PACKET_HEAD_ROOM;
270 dev->needed_tailroom = noise_encrypted_len(MESSAGE_PADDING_MULTIPLE);
271 dev->type = ARPHRD_NONE;
272 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
273 dev->priv_flags |= IFF_NO_QUEUE;
274 dev->features |= NETIF_F_LLTX;
275 dev->features |= WG_NETDEV_FEATURES;
276 dev->hw_features |= WG_NETDEV_FEATURES;
277 dev->hw_enc_features |= WG_NETDEV_FEATURES;
278 dev->mtu = ETH_DATA_LEN - overhead;
279 dev->max_mtu = round_down(INT_MAX, MESSAGE_PADDING_MULTIPLE) - overhead;
280
281 SET_NETDEV_DEVTYPE(dev, &device_type);
282
283 /* We need to keep the dst around in case of icmp replies. */
284 netif_keep_dst(dev);
285
286 memset(wg, 0, sizeof(*wg));
287 wg->dev = dev;
288}
289
290static int wg_newlink(struct net *src_net, struct net_device *dev,
291 struct nlattr *tb[], struct nlattr *data[],
292 struct netlink_ext_ack *extack)
293{
294 struct wg_device *wg = netdev_priv(dev);
295 int ret = -ENOMEM;
296
297 rcu_assign_pointer(wg->creating_net, src_net);
298 init_rwsem(&wg->static_identity.lock);
299 mutex_init(&wg->socket_update_lock);
300 mutex_init(&wg->device_update_lock);
301 skb_queue_head_init(&wg->incoming_handshakes);
302 wg_allowedips_init(&wg->peer_allowedips);
303 wg_cookie_checker_init(&wg->cookie_checker, wg);
304 INIT_LIST_HEAD(&wg->peer_list);
305 wg->device_update_gen = 1;
306
307 wg->peer_hashtable = wg_pubkey_hashtable_alloc();
308 if (!wg->peer_hashtable)
309 return ret;
310
311 wg->index_hashtable = wg_index_hashtable_alloc();
312 if (!wg->index_hashtable)
313 goto err_free_peer_hashtable;
314
315 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
316 if (!dev->tstats)
317 goto err_free_index_hashtable;
318
319 wg->incoming_handshakes_worker =
320 wg_packet_percpu_multicore_worker_alloc(
321 wg_packet_handshake_receive_worker, wg);
322 if (!wg->incoming_handshakes_worker)
323 goto err_free_tstats;
324
325 wg->handshake_receive_wq = alloc_workqueue("wg-kex-%s",
326 WQ_CPU_INTENSIVE | WQ_FREEZABLE, 0, dev->name);
327 if (!wg->handshake_receive_wq)
328 goto err_free_incoming_handshakes;
329
330 wg->handshake_send_wq = alloc_workqueue("wg-kex-%s",
331 WQ_UNBOUND | WQ_FREEZABLE, 0, dev->name);
332 if (!wg->handshake_send_wq)
333 goto err_destroy_handshake_receive;
334
335 wg->packet_crypt_wq = alloc_workqueue("wg-crypt-%s",
336 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 0, dev->name);
337 if (!wg->packet_crypt_wq)
338 goto err_destroy_handshake_send;
339
340 ret = wg_packet_queue_init(&wg->encrypt_queue, wg_packet_encrypt_worker,
341 MAX_QUEUED_PACKETS);
342 if (ret < 0)
343 goto err_destroy_packet_crypt;
344
345 ret = wg_packet_queue_init(&wg->decrypt_queue, wg_packet_decrypt_worker,
346 MAX_QUEUED_PACKETS);
347 if (ret < 0)
348 goto err_free_encrypt_queue;
349
350 ret = wg_ratelimiter_init();
351 if (ret < 0)
352 goto err_free_decrypt_queue;
353
354 ret = register_netdevice(dev);
355 if (ret < 0)
356 goto err_uninit_ratelimiter;
357
358 list_add(&wg->device_list, &device_list);
359
360 /* We wait until the end to assign priv_destructor, so that
361 * register_netdevice doesn't call it for us if it fails.
362 */
363 dev->priv_destructor = wg_destruct;
364
365 pr_debug("%s: Interface created\n", dev->name);
366 return ret;
367
368err_uninit_ratelimiter:
369 wg_ratelimiter_uninit();
370err_free_decrypt_queue:
371 wg_packet_queue_free(&wg->decrypt_queue);
372err_free_encrypt_queue:
373 wg_packet_queue_free(&wg->encrypt_queue);
374err_destroy_packet_crypt:
375 destroy_workqueue(wg->packet_crypt_wq);
376err_destroy_handshake_send:
377 destroy_workqueue(wg->handshake_send_wq);
378err_destroy_handshake_receive:
379 destroy_workqueue(wg->handshake_receive_wq);
380err_free_incoming_handshakes:
381 free_percpu(wg->incoming_handshakes_worker);
382err_free_tstats:
383 free_percpu(dev->tstats);
384err_free_index_hashtable:
385 kvfree(wg->index_hashtable);
386err_free_peer_hashtable:
387 kvfree(wg->peer_hashtable);
388 return ret;
389}
390
391static struct rtnl_link_ops link_ops __read_mostly = {
392 .kind = KBUILD_MODNAME,
393 .priv_size = sizeof(struct wg_device),
394 .setup = wg_setup,
395 .newlink = wg_newlink,
396};
397
398static void wg_netns_pre_exit(struct net *net)
399{
400 struct wg_device *wg;
401
402 rtnl_lock();
403 list_for_each_entry(wg, &device_list, device_list) {
404 if (rcu_access_pointer(wg->creating_net) == net) {
405 pr_debug("%s: Creating namespace exiting\n", wg->dev->name);
406 netif_carrier_off(wg->dev);
407 mutex_lock(&wg->device_update_lock);
408 rcu_assign_pointer(wg->creating_net, NULL);
409 wg_socket_reinit(wg, NULL, NULL);
410 mutex_unlock(&wg->device_update_lock);
411 }
412 }
413 rtnl_unlock();
414}
415
416static struct pernet_operations pernet_ops = {
417 .pre_exit = wg_netns_pre_exit
418};
419
420int __init wg_device_init(void)
421{
422 int ret;
423
424#ifdef CONFIG_PM_SLEEP
425 ret = register_pm_notifier(&pm_notifier);
426 if (ret)
427 return ret;
428#endif
429
430 ret = register_pernet_device(&pernet_ops);
431 if (ret)
432 goto error_pm;
433
434 ret = rtnl_link_register(&link_ops);
435 if (ret)
436 goto error_pernet;
437
438 return 0;
439
440error_pernet:
441 unregister_pernet_device(&pernet_ops);
442error_pm:
443#ifdef CONFIG_PM_SLEEP
444 unregister_pm_notifier(&pm_notifier);
445#endif
446 return ret;
447}
448
449void wg_device_uninit(void)
450{
451 rtnl_link_unregister(&link_ops);
452 unregister_pernet_device(&pernet_ops);
453#ifdef CONFIG_PM_SLEEP
454 unregister_pm_notifier(&pm_notifier);
455#endif
456 rcu_barrier();
457}