1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * INET An implementation of the TCP Authentication Option (TCP-AO).
4 * See RFC5925.
5 *
6 * Authors: Dmitry Safonov <dima@arista.com>
7 * Francesco Ruggeri <fruggeri@arista.com>
8 * Salam Noureddine <noureddine@arista.com>
9 */
10 #define pr_fmt(fmt) "TCP: " fmt
11
12 #include <crypto/hash.h>
13 #include <linux/inetdevice.h>
14 #include <linux/tcp.h>
15
16 #include <net/tcp.h>
17 #include <net/ipv6.h>
18 #include <net/icmp.h>
19 #include <trace/events/tcp.h>
20
21 DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_ao_needed, HZ);
22
23 int tcp_ao_calc_traffic_key(struct tcp_ao_key *mkt, u8 *key, void *ctx,
24 unsigned int len, struct tcp_sigpool *hp)
25 {
26 struct scatterlist sg;
27 int ret;
28
29 if (crypto_ahash_setkey(crypto_ahash_reqtfm(hp->req),
30 mkt->key, mkt->keylen))
31 goto clear_hash;
32
33 ret = crypto_ahash_init(hp->req);
34 if (ret)
35 goto clear_hash;
36
37 sg_init_one(&sg, ctx, len);
38 ahash_request_set_crypt(hp->req, &sg, key, len);
39 crypto_ahash_update(hp->req);
40
41 ret = crypto_ahash_final(hp->req);
42 if (ret)
43 goto clear_hash;
44
45 return 0;
46 clear_hash:
47 memset(key, 0, tcp_ao_digest_size(mkt));
48 return 1;
49 }
50
51 bool tcp_ao_ignore_icmp(const struct sock *sk, int family, int type, int code)
52 {
53 bool ignore_icmp = false;
54 struct tcp_ao_info *ao;
55
56 if (!static_branch_unlikely(&tcp_ao_needed.key))
57 return false;
58
59 /* RFC5925, 7.8:
60 * >> A TCP-AO implementation MUST default to ignore incoming ICMPv4
61 * messages of Type 3 (destination unreachable), Codes 2-4 (protocol
62 * unreachable, port unreachable, and fragmentation needed -- ’hard
63 * errors’), and ICMPv6 Type 1 (destination unreachable), Code 1
64 * (administratively prohibited) and Code 4 (port unreachable) intended
65 * for connections in synchronized states (ESTABLISHED, FIN-WAIT-1, FIN-
66 * WAIT-2, CLOSE-WAIT, CLOSING, LAST-ACK, TIME-WAIT) that match MKTs.
67 */
68 if (family == AF_INET) {
69 if (type != ICMP_DEST_UNREACH)
70 return false;
71 if (code < ICMP_PROT_UNREACH || code > ICMP_FRAG_NEEDED)
72 return false;
73 } else {
74 if (type != ICMPV6_DEST_UNREACH)
75 return false;
76 if (code != ICMPV6_ADM_PROHIBITED && code != ICMPV6_PORT_UNREACH)
77 return false;
78 }
79
80 rcu_read_lock();
81 switch (sk->sk_state) {
82 case TCP_TIME_WAIT:
83 ao = rcu_dereference(tcp_twsk(sk)->ao_info);
84 break;
85 case TCP_SYN_SENT:
86 case TCP_SYN_RECV:
87 case TCP_LISTEN:
88 case TCP_NEW_SYN_RECV:
89 /* RFC5925 specifies to ignore ICMPs *only* on connections
90 * in synchronized states.
91 */
92 rcu_read_unlock();
93 return false;
94 default:
95 ao = rcu_dereference(tcp_sk(sk)->ao_info);
96 }
97
98 if (ao && !ao->accept_icmps) {
99 ignore_icmp = true;
100 __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAODROPPEDICMPS);
101 atomic64_inc(&ao->counters.dropped_icmp);
102 }
103 rcu_read_unlock();
104
105 return ignore_icmp;
106 }
107
108 /* Optimized version of tcp_ao_do_lookup(): only for sockets for which
109 * it's known that the keys in ao_info are matching peer's
110 * family/address/VRF/etc.
111 */
112 struct tcp_ao_key *tcp_ao_established_key(struct tcp_ao_info *ao,
113 int sndid, int rcvid)
114 {
115 struct tcp_ao_key *key;
116
117 hlist_for_each_entry_rcu(key, &ao->head, node) {
118 if ((sndid >= 0 && key->sndid != sndid) ||
119 (rcvid >= 0 && key->rcvid != rcvid))
120 continue;
121 return key;
122 }
123
124 return NULL;
125 }
126
127 static int ipv4_prefix_cmp(const struct in_addr *addr1,
128 const struct in_addr *addr2,
129 unsigned int prefixlen)
130 {
131 __be32 mask = inet_make_mask(prefixlen);
132 __be32 a1 = addr1->s_addr & mask;
133 __be32 a2 = addr2->s_addr & mask;
134
135 if (a1 == a2)
136 return 0;
137 return memcmp(&a1, &a2, sizeof(a1));
138 }
139
140 static int __tcp_ao_key_cmp(const struct tcp_ao_key *key, int l3index,
141 const union tcp_ao_addr *addr, u8 prefixlen,
142 int family, int sndid, int rcvid)
143 {
144 if (sndid >= 0 && key->sndid != sndid)
145 return (key->sndid > sndid) ? 1 : -1;
146 if (rcvid >= 0 && key->rcvid != rcvid)
147 return (key->rcvid > rcvid) ? 1 : -1;
148 if (l3index >= 0 && (key->keyflags & TCP_AO_KEYF_IFINDEX)) {
149 if (key->l3index != l3index)
150 return (key->l3index > l3index) ? 1 : -1;
151 }
152
153 if (family == AF_UNSPEC)
154 return 0;
155 if (key->family != family)
156 return (key->family > family) ? 1 : -1;
157
158 if (family == AF_INET) {
159 if (ntohl(key->addr.a4.s_addr) == INADDR_ANY)
160 return 0;
161 if (ntohl(addr->a4.s_addr) == INADDR_ANY)
162 return 0;
163 return ipv4_prefix_cmp(&key->addr.a4, &addr->a4, prefixlen);
164 #if IS_ENABLED(CONFIG_IPV6)
165 } else {
166 if (ipv6_addr_any(&key->addr.a6) || ipv6_addr_any(&addr->a6))
167 return 0;
168 if (ipv6_prefix_equal(&key->addr.a6, &addr->a6, prefixlen))
169 return 0;
170 return memcmp(&key->addr.a6, &addr->a6, sizeof(addr->a6));
171 #endif
172 }
173 return -1;
174 }
175
176 static int tcp_ao_key_cmp(const struct tcp_ao_key *key, int l3index,
177 const union tcp_ao_addr *addr, u8 prefixlen,
178 int family, int sndid, int rcvid)
179 {
180 #if IS_ENABLED(CONFIG_IPV6)
181 if (family == AF_INET6 && ipv6_addr_v4mapped(&addr->a6)) {
182 __be32 addr4 = addr->a6.s6_addr32[3];
183
184 return __tcp_ao_key_cmp(key, l3index,
185 (union tcp_ao_addr *)&addr4,
186 prefixlen, AF_INET, sndid, rcvid);
187 }
188 #endif
189 return __tcp_ao_key_cmp(key, l3index, addr,
190 prefixlen, family, sndid, rcvid);
191 }
192
193 static struct tcp_ao_key *__tcp_ao_do_lookup(const struct sock *sk, int l3index,
194 const union tcp_ao_addr *addr, int family, u8 prefix,
195 int sndid, int rcvid)
196 {
197 struct tcp_ao_key *key;
198 struct tcp_ao_info *ao;
199
200 if (!static_branch_unlikely(&tcp_ao_needed.key))
201 return NULL;
202
203 ao = rcu_dereference_check(tcp_sk(sk)->ao_info,
204 lockdep_sock_is_held(sk));
205 if (!ao)
206 return NULL;
207
208 hlist_for_each_entry_rcu(key, &ao->head, node) {
209 u8 prefixlen = min(prefix, key->prefixlen);
210
211 if (!tcp_ao_key_cmp(key, l3index, addr, prefixlen,
212 family, sndid, rcvid))
213 return key;
214 }
215 return NULL;
216 }
217
218 struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk, int l3index,
219 const union tcp_ao_addr *addr,
220 int family, int sndid, int rcvid)
221 {
222 return __tcp_ao_do_lookup(sk, l3index, addr, family, U8_MAX, sndid, rcvid);
223 }
224
225 static struct tcp_ao_info *tcp_ao_alloc_info(gfp_t flags)
226 {
227 struct tcp_ao_info *ao;
228
229 ao = kzalloc(sizeof(*ao), flags);
230 if (!ao)
231 return NULL;
232 INIT_HLIST_HEAD(&ao->head);
233 refcount_set(&ao->refcnt, 1);
234
235 return ao;
236 }
237
238 static void tcp_ao_link_mkt(struct tcp_ao_info *ao, struct tcp_ao_key *mkt)
239 {
240 hlist_add_head_rcu(&mkt->node, &ao->head);
241 }
242
243 static struct tcp_ao_key *tcp_ao_copy_key(struct sock *sk,
244 struct tcp_ao_key *key)
245 {
246 struct tcp_ao_key *new_key;
247
248 new_key = sock_kmalloc(sk, tcp_ao_sizeof_key(key),
249 GFP_ATOMIC);
250 if (!new_key)
251 return NULL;
252
253 *new_key = *key;
254 INIT_HLIST_NODE(&new_key->node);
255 tcp_sigpool_get(new_key->tcp_sigpool_id);
256 atomic64_set(&new_key->pkt_good, 0);
257 atomic64_set(&new_key->pkt_bad, 0);
258
259 return new_key;
260 }
261
262 static void tcp_ao_key_free_rcu(struct rcu_head *head)
263 {
264 struct tcp_ao_key *key = container_of(head, struct tcp_ao_key, rcu);
265
266 tcp_sigpool_release(key->tcp_sigpool_id);
267 kfree_sensitive(key);
268 }
269
270 static void tcp_ao_info_free_rcu(struct rcu_head *head)
271 {
272 struct tcp_ao_info *ao = container_of(head, struct tcp_ao_info, rcu);
273 struct tcp_ao_key *key;
274 struct hlist_node *n;
275
276 hlist_for_each_entry_safe(key, n, &ao->head, node) {
277 hlist_del(&key->node);
278 tcp_sigpool_release(key->tcp_sigpool_id);
279 kfree_sensitive(key);
280 }
281 kfree(ao);
282 static_branch_slow_dec_deferred(&tcp_ao_needed);
283 }
284
285 static void tcp_ao_sk_omem_free(struct sock *sk, struct tcp_ao_info *ao)
286 {
287 size_t total_ao_sk_mem = 0;
288 struct tcp_ao_key *key;
289
290 hlist_for_each_entry(key, &ao->head, node)
291 total_ao_sk_mem += tcp_ao_sizeof_key(key);
292 atomic_sub(total_ao_sk_mem, &sk->sk_omem_alloc);
293 }
294
295 void tcp_ao_destroy_sock(struct sock *sk, bool twsk)
296 {
297 struct tcp_ao_info *ao;
298
299 if (twsk) {
300 ao = rcu_dereference_protected(tcp_twsk(sk)->ao_info, 1);
301 rcu_assign_pointer(tcp_twsk(sk)->ao_info, NULL);
302 } else {
303 ao = rcu_dereference_protected(tcp_sk(sk)->ao_info, 1);
304 rcu_assign_pointer(tcp_sk(sk)->ao_info, NULL);
305 }
306
307 if (!ao || !refcount_dec_and_test(&ao->refcnt))
308 return;
309
310 if (!twsk)
311 tcp_ao_sk_omem_free(sk, ao);
312 call_rcu(&ao->rcu, tcp_ao_info_free_rcu);
313 }
314
315 void tcp_ao_time_wait(struct tcp_timewait_sock *tcptw, struct tcp_sock *tp)
316 {
317 struct tcp_ao_info *ao_info = rcu_dereference_protected(tp->ao_info, 1);
318
319 if (ao_info) {
320 struct tcp_ao_key *key;
321 struct hlist_node *n;
322 int omem = 0;
323
324 hlist_for_each_entry_safe(key, n, &ao_info->head, node) {
325 omem += tcp_ao_sizeof_key(key);
326 }
327
328 refcount_inc(&ao_info->refcnt);
329 atomic_sub(omem, &(((struct sock *)tp)->sk_omem_alloc));
330 rcu_assign_pointer(tcptw->ao_info, ao_info);
331 } else {
332 tcptw->ao_info = NULL;
333 }
334 }
335
336 /* 4 tuple and ISNs are expected in NBO */
337 static int tcp_v4_ao_calc_key(struct tcp_ao_key *mkt, u8 *key,
338 __be32 saddr, __be32 daddr,
339 __be16 sport, __be16 dport,
340 __be32 sisn, __be32 disn)
341 {
342 /* See RFC5926 3.1.1 */
343 struct kdf_input_block {
344 u8 counter;
345 u8 label[6];
346 struct tcp4_ao_context ctx;
347 __be16 outlen;
348 } __packed * tmp;
349 struct tcp_sigpool hp;
350 int err;
351
352 err = tcp_sigpool_start(mkt->tcp_sigpool_id, &hp);
353 if (err)
354 return err;
355
356 tmp = hp.scratch;
357 tmp->counter = 1;
358 memcpy(tmp->label, "TCP-AO", 6);
359 tmp->ctx.saddr = saddr;
360 tmp->ctx.daddr = daddr;
361 tmp->ctx.sport = sport;
362 tmp->ctx.dport = dport;
363 tmp->ctx.sisn = sisn;
364 tmp->ctx.disn = disn;
365 tmp->outlen = htons(tcp_ao_digest_size(mkt) * 8); /* in bits */
366
367 err = tcp_ao_calc_traffic_key(mkt, key, tmp, sizeof(*tmp), &hp);
368 tcp_sigpool_end(&hp);
369
370 return err;
371 }
372
373 int tcp_v4_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key,
374 const struct sock *sk,
375 __be32 sisn, __be32 disn, bool send)
376 {
377 if (send)
378 return tcp_v4_ao_calc_key(mkt, key, sk->sk_rcv_saddr,
379 sk->sk_daddr, htons(sk->sk_num),
380 sk->sk_dport, sisn, disn);
381 else
382 return tcp_v4_ao_calc_key(mkt, key, sk->sk_daddr,
383 sk->sk_rcv_saddr, sk->sk_dport,
384 htons(sk->sk_num), disn, sisn);
385 }
386
387 static int tcp_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key,
388 const struct sock *sk,
389 __be32 sisn, __be32 disn, bool send)
390 {
391 if (mkt->family == AF_INET)
392 return tcp_v4_ao_calc_key_sk(mkt, key, sk, sisn, disn, send);
393 #if IS_ENABLED(CONFIG_IPV6)
394 else if (mkt->family == AF_INET6)
395 return tcp_v6_ao_calc_key_sk(mkt, key, sk, sisn, disn, send);
396 #endif
397 else
398 return -EOPNOTSUPP;
399 }
400
401 int tcp_v4_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key,
402 struct request_sock *req)
403 {
404 struct inet_request_sock *ireq = inet_rsk(req);
405
406 return tcp_v4_ao_calc_key(mkt, key,
407 ireq->ir_loc_addr, ireq->ir_rmt_addr,
408 htons(ireq->ir_num), ireq->ir_rmt_port,
409 htonl(tcp_rsk(req)->snt_isn),
410 htonl(tcp_rsk(req)->rcv_isn));
411 }
412
413 static int tcp_v4_ao_calc_key_skb(struct tcp_ao_key *mkt, u8 *key,
414 const struct sk_buff *skb,
415 __be32 sisn, __be32 disn)
416 {
417 const struct iphdr *iph = ip_hdr(skb);
418 const struct tcphdr *th = tcp_hdr(skb);
419
420 return tcp_v4_ao_calc_key(mkt, key, iph->saddr, iph->daddr,
421 th->source, th->dest, sisn, disn);
422 }
423
424 static int tcp_ao_calc_key_skb(struct tcp_ao_key *mkt, u8 *key,
425 const struct sk_buff *skb,
426 __be32 sisn, __be32 disn, int family)
427 {
428 if (family == AF_INET)
429 return tcp_v4_ao_calc_key_skb(mkt, key, skb, sisn, disn);
430 #if IS_ENABLED(CONFIG_IPV6)
431 else if (family == AF_INET6)
432 return tcp_v6_ao_calc_key_skb(mkt, key, skb, sisn, disn);
433 #endif
434 return -EAFNOSUPPORT;
435 }
436
437 static int tcp_v4_ao_hash_pseudoheader(struct tcp_sigpool *hp,
438 __be32 daddr, __be32 saddr,
439 int nbytes)
440 {
441 struct tcp4_pseudohdr *bp;
442 struct scatterlist sg;
443
444 bp = hp->scratch;
445 bp->saddr = saddr;
446 bp->daddr = daddr;
447 bp->pad = 0;
448 bp->protocol = IPPROTO_TCP;
449 bp->len = cpu_to_be16(nbytes);
450
451 sg_init_one(&sg, bp, sizeof(*bp));
452 ahash_request_set_crypt(hp->req, &sg, NULL, sizeof(*bp));
453 return crypto_ahash_update(hp->req);
454 }
455
456 static int tcp_ao_hash_pseudoheader(unsigned short int family,
457 const struct sock *sk,
458 const struct sk_buff *skb,
459 struct tcp_sigpool *hp, int nbytes)
460 {
461 const struct tcphdr *th = tcp_hdr(skb);
462
463 /* TODO: Can we rely on checksum being zero to mean outbound pkt? */
464 if (!th->check) {
465 if (family == AF_INET)
466 return tcp_v4_ao_hash_pseudoheader(hp, sk->sk_daddr,
467 sk->sk_rcv_saddr, skb->len);
468 #if IS_ENABLED(CONFIG_IPV6)
469 else if (family == AF_INET6)
470 return tcp_v6_ao_hash_pseudoheader(hp, &sk->sk_v6_daddr,
471 &sk->sk_v6_rcv_saddr, skb->len);
472 #endif
473 else
474 return -EAFNOSUPPORT;
475 }
476
477 if (family == AF_INET) {
478 const struct iphdr *iph = ip_hdr(skb);
479
480 return tcp_v4_ao_hash_pseudoheader(hp, iph->daddr,
481 iph->saddr, skb->len);
482 #if IS_ENABLED(CONFIG_IPV6)
483 } else if (family == AF_INET6) {
484 const struct ipv6hdr *iph = ipv6_hdr(skb);
485
486 return tcp_v6_ao_hash_pseudoheader(hp, &iph->daddr,
487 &iph->saddr, skb->len);
488 #endif
489 }
490 return -EAFNOSUPPORT;
491 }
492
493 u32 tcp_ao_compute_sne(u32 next_sne, u32 next_seq, u32 seq)
494 {
495 u32 sne = next_sne;
496
497 if (before(seq, next_seq)) {
498 if (seq > next_seq)
499 sne--;
500 } else {
501 if (seq < next_seq)
502 sne++;
503 }
504
505 return sne;
506 }
507
508 /* tcp_ao_hash_sne(struct tcp_sigpool *hp)
509 * @hp - used for hashing
510 * @sne - sne value
511 */
512 static int tcp_ao_hash_sne(struct tcp_sigpool *hp, u32 sne)
513 {
514 struct scatterlist sg;
515 __be32 *bp;
516
517 bp = (__be32 *)hp->scratch;
518 *bp = htonl(sne);
519
520 sg_init_one(&sg, bp, sizeof(*bp));
521 ahash_request_set_crypt(hp->req, &sg, NULL, sizeof(*bp));
522 return crypto_ahash_update(hp->req);
523 }
524
525 static int tcp_ao_hash_header(struct tcp_sigpool *hp,
526 const struct tcphdr *th,
527 bool exclude_options, u8 *hash,
528 int hash_offset, int hash_len)
529 {
530 struct scatterlist sg;
531 u8 *hdr = hp->scratch;
532 int err, len;
533
534 /* We are not allowed to change tcphdr, make a local copy */
535 if (exclude_options) {
536 len = sizeof(*th) + sizeof(struct tcp_ao_hdr) + hash_len;
537 memcpy(hdr, th, sizeof(*th));
538 memcpy(hdr + sizeof(*th),
539 (u8 *)th + hash_offset - sizeof(struct tcp_ao_hdr),
540 sizeof(struct tcp_ao_hdr));
541 memset(hdr + sizeof(*th) + sizeof(struct tcp_ao_hdr),
542 0, hash_len);
543 ((struct tcphdr *)hdr)->check = 0;
544 } else {
545 len = th->doff << 2;
546 memcpy(hdr, th, len);
547 /* zero out tcp-ao hash */
548 ((struct tcphdr *)hdr)->check = 0;
549 memset(hdr + hash_offset, 0, hash_len);
550 }
551
552 sg_init_one(&sg, hdr, len);
553 ahash_request_set_crypt(hp->req, &sg, NULL, len);
554 err = crypto_ahash_update(hp->req);
555 WARN_ON_ONCE(err != 0);
556 return err;
557 }
558
559 int tcp_ao_hash_hdr(unsigned short int family, char *ao_hash,
560 struct tcp_ao_key *key, const u8 *tkey,
561 const union tcp_ao_addr *daddr,
562 const union tcp_ao_addr *saddr,
563 const struct tcphdr *th, u32 sne)
564 {
565 int tkey_len = tcp_ao_digest_size(key);
566 int hash_offset = ao_hash - (char *)th;
567 struct tcp_sigpool hp;
568 void *hash_buf = NULL;
569
570 hash_buf = kmalloc(tkey_len, GFP_ATOMIC);
571 if (!hash_buf)
572 goto clear_hash_noput;
573
574 if (tcp_sigpool_start(key->tcp_sigpool_id, &hp))
575 goto clear_hash_noput;
576
577 if (crypto_ahash_setkey(crypto_ahash_reqtfm(hp.req), tkey, tkey_len))
578 goto clear_hash;
579
580 if (crypto_ahash_init(hp.req))
581 goto clear_hash;
582
583 if (tcp_ao_hash_sne(&hp, sne))
584 goto clear_hash;
585 if (family == AF_INET) {
586 if (tcp_v4_ao_hash_pseudoheader(&hp, daddr->a4.s_addr,
587 saddr->a4.s_addr, th->doff * 4))
588 goto clear_hash;
589 #if IS_ENABLED(CONFIG_IPV6)
590 } else if (family == AF_INET6) {
591 if (tcp_v6_ao_hash_pseudoheader(&hp, &daddr->a6,
592 &saddr->a6, th->doff * 4))
593 goto clear_hash;
594 #endif
595 } else {
596 WARN_ON_ONCE(1);
597 goto clear_hash;
598 }
599 if (tcp_ao_hash_header(&hp, th,
600 !!(key->keyflags & TCP_AO_KEYF_EXCLUDE_OPT),
601 ao_hash, hash_offset, tcp_ao_maclen(key)))
602 goto clear_hash;
603 ahash_request_set_crypt(hp.req, NULL, hash_buf, 0);
604 if (crypto_ahash_final(hp.req))
605 goto clear_hash;
606
607 memcpy(ao_hash, hash_buf, tcp_ao_maclen(key));
608 tcp_sigpool_end(&hp);
609 kfree(hash_buf);
610 return 0;
611
612 clear_hash:
613 tcp_sigpool_end(&hp);
614 clear_hash_noput:
615 memset(ao_hash, 0, tcp_ao_maclen(key));
616 kfree(hash_buf);
617 return 1;
618 }
619
620 int tcp_ao_hash_skb(unsigned short int family,
621 char *ao_hash, struct tcp_ao_key *key,
622 const struct sock *sk, const struct sk_buff *skb,
623 const u8 *tkey, int hash_offset, u32 sne)
624 {
625 const struct tcphdr *th = tcp_hdr(skb);
626 int tkey_len = tcp_ao_digest_size(key);
627 struct tcp_sigpool hp;
628 void *hash_buf = NULL;
629
630 hash_buf = kmalloc(tkey_len, GFP_ATOMIC);
631 if (!hash_buf)
632 goto clear_hash_noput;
633
634 if (tcp_sigpool_start(key->tcp_sigpool_id, &hp))
635 goto clear_hash_noput;
636
637 if (crypto_ahash_setkey(crypto_ahash_reqtfm(hp.req), tkey, tkey_len))
638 goto clear_hash;
639
640 /* For now use sha1 by default. Depends on alg in tcp_ao_key */
641 if (crypto_ahash_init(hp.req))
642 goto clear_hash;
643
644 if (tcp_ao_hash_sne(&hp, sne))
645 goto clear_hash;
646 if (tcp_ao_hash_pseudoheader(family, sk, skb, &hp, skb->len))
647 goto clear_hash;
648 if (tcp_ao_hash_header(&hp, th,
649 !!(key->keyflags & TCP_AO_KEYF_EXCLUDE_OPT),
650 ao_hash, hash_offset, tcp_ao_maclen(key)))
651 goto clear_hash;
652 if (tcp_sigpool_hash_skb_data(&hp, skb, th->doff << 2))
653 goto clear_hash;
654 ahash_request_set_crypt(hp.req, NULL, hash_buf, 0);
655 if (crypto_ahash_final(hp.req))
656 goto clear_hash;
657
658 memcpy(ao_hash, hash_buf, tcp_ao_maclen(key));
659 tcp_sigpool_end(&hp);
660 kfree(hash_buf);
661 return 0;
662
663 clear_hash:
664 tcp_sigpool_end(&hp);
665 clear_hash_noput:
666 memset(ao_hash, 0, tcp_ao_maclen(key));
667 kfree(hash_buf);
668 return 1;
669 }
670
671 int tcp_v4_ao_hash_skb(char *ao_hash, struct tcp_ao_key *key,
672 const struct sock *sk, const struct sk_buff *skb,
673 const u8 *tkey, int hash_offset, u32 sne)
674 {
675 return tcp_ao_hash_skb(AF_INET, ao_hash, key, sk, skb,
676 tkey, hash_offset, sne);
677 }
678
679 int tcp_v4_ao_synack_hash(char *ao_hash, struct tcp_ao_key *ao_key,
680 struct request_sock *req, const struct sk_buff *skb,
681 int hash_offset, u32 sne)
682 {
683 void *hash_buf = NULL;
684 int err;
685
686 hash_buf = kmalloc(tcp_ao_digest_size(ao_key), GFP_ATOMIC);
687 if (!hash_buf)
688 return -ENOMEM;
689
690 err = tcp_v4_ao_calc_key_rsk(ao_key, hash_buf, req);
691 if (err)
692 goto out;
693
694 err = tcp_ao_hash_skb(AF_INET, ao_hash, ao_key, req_to_sk(req), skb,
695 hash_buf, hash_offset, sne);
696 out:
697 kfree(hash_buf);
698 return err;
699 }
700
701 struct tcp_ao_key *tcp_v4_ao_lookup_rsk(const struct sock *sk,
702 struct request_sock *req,
703 int sndid, int rcvid)
704 {
705 struct inet_request_sock *ireq = inet_rsk(req);
706 union tcp_ao_addr *addr = (union tcp_ao_addr *)&ireq->ir_rmt_addr;
707 int l3index;
708
709 l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif);
710 return tcp_ao_do_lookup(sk, l3index, addr, AF_INET, sndid, rcvid);
711 }
712
713 struct tcp_ao_key *tcp_v4_ao_lookup(const struct sock *sk, struct sock *addr_sk,
714 int sndid, int rcvid)
715 {
716 int l3index = l3mdev_master_ifindex_by_index(sock_net(sk),
717 addr_sk->sk_bound_dev_if);
718 union tcp_ao_addr *addr = (union tcp_ao_addr *)&addr_sk->sk_daddr;
719
720 return tcp_ao_do_lookup(sk, l3index, addr, AF_INET, sndid, rcvid);
721 }
722
723 int tcp_ao_prepare_reset(const struct sock *sk, struct sk_buff *skb,
724 const struct tcp_ao_hdr *aoh, int l3index, u32 seq,
725 struct tcp_ao_key **key, char **traffic_key,
726 bool *allocated_traffic_key, u8 *keyid, u32 *sne)
727 {
728 const struct tcphdr *th = tcp_hdr(skb);
729 struct tcp_ao_info *ao_info;
730
731 *allocated_traffic_key = false;
732 /* If there's no socket - than initial sisn/disn are unknown.
733 * Drop the segment. RFC5925 (7.7) advises to require graceful
734 * restart [RFC4724]. Alternatively, the RFC5925 advises to
735 * save/restore traffic keys before/after reboot.
736 * Linux TCP-AO support provides TCP_AO_ADD_KEY and TCP_AO_REPAIR
737 * options to restore a socket post-reboot.
738 */
739 if (!sk)
740 return -ENOTCONN;
741
742 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV)) {
743 unsigned int family = READ_ONCE(sk->sk_family);
744 union tcp_ao_addr *addr;
745 __be32 disn, sisn;
746
747 if (sk->sk_state == TCP_NEW_SYN_RECV) {
748 struct request_sock *req = inet_reqsk(sk);
749
750 sisn = htonl(tcp_rsk(req)->rcv_isn);
751 disn = htonl(tcp_rsk(req)->snt_isn);
752 *sne = tcp_ao_compute_sne(0, tcp_rsk(req)->snt_isn, seq);
753 } else {
754 sisn = th->seq;
755 disn = 0;
756 }
757 if (IS_ENABLED(CONFIG_IPV6) && family == AF_INET6)
758 addr = (union tcp_md5_addr *)&ipv6_hdr(skb)->saddr;
759 else
760 addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr;
761 #if IS_ENABLED(CONFIG_IPV6)
762 if (family == AF_INET6 && ipv6_addr_v4mapped(&sk->sk_v6_daddr))
763 family = AF_INET;
764 #endif
765
766 sk = sk_const_to_full_sk(sk);
767 ao_info = rcu_dereference(tcp_sk(sk)->ao_info);
768 if (!ao_info)
769 return -ENOENT;
770 *key = tcp_ao_do_lookup(sk, l3index, addr, family,
771 -1, aoh->rnext_keyid);
772 if (!*key)
773 return -ENOENT;
774 *traffic_key = kmalloc(tcp_ao_digest_size(*key), GFP_ATOMIC);
775 if (!*traffic_key)
776 return -ENOMEM;
777 *allocated_traffic_key = true;
778 if (tcp_ao_calc_key_skb(*key, *traffic_key, skb,
779 sisn, disn, family))
780 return -1;
781 *keyid = (*key)->rcvid;
782 } else {
783 struct tcp_ao_key *rnext_key;
784 u32 snd_basis;
785
786 if (sk->sk_state == TCP_TIME_WAIT) {
787 ao_info = rcu_dereference(tcp_twsk(sk)->ao_info);
788 snd_basis = tcp_twsk(sk)->tw_snd_nxt;
789 } else {
790 ao_info = rcu_dereference(tcp_sk(sk)->ao_info);
791 snd_basis = tcp_sk(sk)->snd_una;
792 }
793 if (!ao_info)
794 return -ENOENT;
795
796 *key = tcp_ao_established_key(ao_info, aoh->rnext_keyid, -1);
797 if (!*key)
798 return -ENOENT;
799 *traffic_key = snd_other_key(*key);
800 rnext_key = READ_ONCE(ao_info->rnext_key);
801 *keyid = rnext_key->rcvid;
802 *sne = tcp_ao_compute_sne(READ_ONCE(ao_info->snd_sne),
803 snd_basis, seq);
804 }
805 return 0;
806 }
807
808 int tcp_ao_transmit_skb(struct sock *sk, struct sk_buff *skb,
809 struct tcp_ao_key *key, struct tcphdr *th,
810 __u8 *hash_location)
811 {
812 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
813 struct tcp_sock *tp = tcp_sk(sk);
814 struct tcp_ao_info *ao;
815 void *tkey_buf = NULL;
816 u8 *traffic_key;
817 u32 sne;
818
819 ao = rcu_dereference_protected(tcp_sk(sk)->ao_info,
820 lockdep_sock_is_held(sk));
821 traffic_key = snd_other_key(key);
822 if (unlikely(tcb->tcp_flags & TCPHDR_SYN)) {
823 __be32 disn;
824
825 if (!(tcb->tcp_flags & TCPHDR_ACK)) {
826 disn = 0;
827 tkey_buf = kmalloc(tcp_ao_digest_size(key), GFP_ATOMIC);
828 if (!tkey_buf)
829 return -ENOMEM;
830 traffic_key = tkey_buf;
831 } else {
832 disn = ao->risn;
833 }
834 tp->af_specific->ao_calc_key_sk(key, traffic_key,
835 sk, ao->lisn, disn, true);
836 }
837 sne = tcp_ao_compute_sne(READ_ONCE(ao->snd_sne), READ_ONCE(tp->snd_una),
838 ntohl(th->seq));
839 tp->af_specific->calc_ao_hash(hash_location, key, sk, skb, traffic_key,
840 hash_location - (u8 *)th, sne);
841 kfree(tkey_buf);
842 return 0;
843 }
844
845 static struct tcp_ao_key *tcp_ao_inbound_lookup(unsigned short int family,
846 const struct sock *sk, const struct sk_buff *skb,
847 int sndid, int rcvid, int l3index)
848 {
849 if (family == AF_INET) {
850 const struct iphdr *iph = ip_hdr(skb);
851
852 return tcp_ao_do_lookup(sk, l3index,
853 (union tcp_ao_addr *)&iph->saddr,
854 AF_INET, sndid, rcvid);
855 } else {
856 const struct ipv6hdr *iph = ipv6_hdr(skb);
857
858 return tcp_ao_do_lookup(sk, l3index,
859 (union tcp_ao_addr *)&iph->saddr,
860 AF_INET6, sndid, rcvid);
861 }
862 }
863
864 void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb,
865 struct request_sock *req, unsigned short int family)
866 {
867 struct tcp_request_sock *treq = tcp_rsk(req);
868 const struct tcphdr *th = tcp_hdr(skb);
869 const struct tcp_ao_hdr *aoh;
870 struct tcp_ao_key *key;
871 int l3index;
872
873 /* treq->af_specific is used to perform TCP_AO lookup
874 * in tcp_create_openreq_child().
875 */
876 #if IS_ENABLED(CONFIG_IPV6)
877 if (family == AF_INET6)
878 treq->af_specific = &tcp_request_sock_ipv6_ops;
879 else
880 #endif
881 treq->af_specific = &tcp_request_sock_ipv4_ops;
882
883 treq->used_tcp_ao = false;
884
885 if (tcp_parse_auth_options(th, NULL, &aoh) || !aoh)
886 return;
887
888 l3index = l3mdev_master_ifindex_by_index(sock_net(sk), inet_rsk(req)->ir_iif);
889 key = tcp_ao_inbound_lookup(family, sk, skb, -1, aoh->keyid, l3index);
890 if (!key)
891 /* Key not found, continue without TCP-AO */
892 return;
893
894 treq->ao_rcv_next = aoh->keyid;
895 treq->ao_keyid = aoh->rnext_keyid;
896 treq->used_tcp_ao = true;
897 }
898
899 static enum skb_drop_reason
900 tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb,
901 unsigned short int family, struct tcp_ao_info *info,
902 const struct tcp_ao_hdr *aoh, struct tcp_ao_key *key,
903 u8 *traffic_key, u8 *phash, u32 sne, int l3index)
904 {
905 const struct tcphdr *th = tcp_hdr(skb);
906 u8 maclen = tcp_ao_hdr_maclen(aoh);
907 void *hash_buf = NULL;
908
909 if (maclen != tcp_ao_maclen(key)) {
910 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD);
911 atomic64_inc(&info->counters.pkt_bad);
912 atomic64_inc(&key->pkt_bad);
913 trace_tcp_ao_wrong_maclen(sk, skb, aoh->keyid,
914 aoh->rnext_keyid, maclen);
915 return SKB_DROP_REASON_TCP_AOFAILURE;
916 }
917
918 hash_buf = kmalloc(tcp_ao_digest_size(key), GFP_ATOMIC);
919 if (!hash_buf)
920 return SKB_DROP_REASON_NOT_SPECIFIED;
921
922 /* XXX: make it per-AF callback? */
923 tcp_ao_hash_skb(family, hash_buf, key, sk, skb, traffic_key,
924 (phash - (u8 *)th), sne);
925 if (memcmp(phash, hash_buf, maclen)) {
926 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD);
927 atomic64_inc(&info->counters.pkt_bad);
928 atomic64_inc(&key->pkt_bad);
929 trace_tcp_ao_mismatch(sk, skb, aoh->keyid,
930 aoh->rnext_keyid, maclen);
931 kfree(hash_buf);
932 return SKB_DROP_REASON_TCP_AOFAILURE;
933 }
934 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOGOOD);
935 atomic64_inc(&info->counters.pkt_good);
936 atomic64_inc(&key->pkt_good);
937 kfree(hash_buf);
938 return SKB_NOT_DROPPED_YET;
939 }
940
941 enum skb_drop_reason
942 tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
943 unsigned short int family, const struct request_sock *req,
944 int l3index, const struct tcp_ao_hdr *aoh)
945 {
946 const struct tcphdr *th = tcp_hdr(skb);
947 u8 maclen = tcp_ao_hdr_maclen(aoh);
948 u8 *phash = (u8 *)(aoh + 1); /* hash goes just after the header */
949 struct tcp_ao_info *info;
950 enum skb_drop_reason ret;
951 struct tcp_ao_key *key;
952 __be32 sisn, disn;
953 u8 *traffic_key;
954 int state;
955 u32 sne = 0;
956
957 info = rcu_dereference(tcp_sk(sk)->ao_info);
958 if (!info) {
959 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND);
960 trace_tcp_ao_key_not_found(sk, skb, aoh->keyid,
961 aoh->rnext_keyid, maclen);
962 return SKB_DROP_REASON_TCP_AOUNEXPECTED;
963 }
964
965 if (unlikely(th->syn)) {
966 sisn = th->seq;
967 disn = 0;
968 }
969
970 state = READ_ONCE(sk->sk_state);
971 /* Fast-path */
972 if (likely((1 << state) & TCP_AO_ESTABLISHED)) {
973 enum skb_drop_reason err;
974 struct tcp_ao_key *current_key;
975
976 /* Check if this socket's rnext_key matches the keyid in the
977 * packet. If not we lookup the key based on the keyid
978 * matching the rcvid in the mkt.
979 */
980 key = READ_ONCE(info->rnext_key);
981 if (key->rcvid != aoh->keyid) {
982 key = tcp_ao_established_key(info, -1, aoh->keyid);
983 if (!key)
984 goto key_not_found;
985 }
986
987 /* Delayed retransmitted SYN */
988 if (unlikely(th->syn && !th->ack))
989 goto verify_hash;
990
991 sne = tcp_ao_compute_sne(info->rcv_sne, tcp_sk(sk)->rcv_nxt,
992 ntohl(th->seq));
993 /* Established socket, traffic key are cached */
994 traffic_key = rcv_other_key(key);
995 err = tcp_ao_verify_hash(sk, skb, family, info, aoh, key,
996 traffic_key, phash, sne, l3index);
997 if (err)
998 return err;
999 current_key = READ_ONCE(info->current_key);
1000 /* Key rotation: the peer asks us to use new key (RNext) */
1001 if (unlikely(aoh->rnext_keyid != current_key->sndid)) {
1002 trace_tcp_ao_rnext_request(sk, skb, current_key->sndid,
1003 aoh->rnext_keyid,
1004 tcp_ao_hdr_maclen(aoh));
1005 /* If the key is not found we do nothing. */
1006 key = tcp_ao_established_key(info, aoh->rnext_keyid, -1);
1007 if (key)
1008 /* pairs with tcp_ao_del_cmd */
1009 WRITE_ONCE(info->current_key, key);
1010 }
1011 return SKB_NOT_DROPPED_YET;
1012 }
1013
1014 if (unlikely(state == TCP_CLOSE))
1015 return SKB_DROP_REASON_TCP_CLOSE;
1016
1017 /* Lookup key based on peer address and keyid.
1018 * current_key and rnext_key must not be used on tcp listen
1019 * sockets as otherwise:
1020 * - request sockets would race on those key pointers
1021 * - tcp_ao_del_cmd() allows async key removal
1022 */
1023 key = tcp_ao_inbound_lookup(family, sk, skb, -1, aoh->keyid, l3index);
1024 if (!key)
1025 goto key_not_found;
1026
1027 if (th->syn && !th->ack)
1028 goto verify_hash;
1029
1030 if ((1 << state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV)) {
1031 /* Make the initial syn the likely case here */
1032 if (unlikely(req)) {
1033 sne = tcp_ao_compute_sne(0, tcp_rsk(req)->rcv_isn,
1034 ntohl(th->seq));
1035 sisn = htonl(tcp_rsk(req)->rcv_isn);
1036 disn = htonl(tcp_rsk(req)->snt_isn);
1037 } else if (unlikely(th->ack && !th->syn)) {
1038 /* Possible syncookie packet */
1039 sisn = htonl(ntohl(th->seq) - 1);
1040 disn = htonl(ntohl(th->ack_seq) - 1);
1041 sne = tcp_ao_compute_sne(0, ntohl(sisn),
1042 ntohl(th->seq));
1043 } else if (unlikely(!th->syn)) {
1044 /* no way to figure out initial sisn/disn - drop */
1045 return SKB_DROP_REASON_TCP_FLAGS;
1046 }
1047 } else if ((1 << state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1048 disn = info->lisn;
1049 if (th->syn || th->rst)
1050 sisn = th->seq;
1051 else
1052 sisn = info->risn;
1053 } else {
1054 WARN_ONCE(1, "TCP-AO: Unexpected sk_state %d", state);
1055 return SKB_DROP_REASON_TCP_AOFAILURE;
1056 }
1057 verify_hash:
1058 traffic_key = kmalloc(tcp_ao_digest_size(key), GFP_ATOMIC);
1059 if (!traffic_key)
1060 return SKB_DROP_REASON_NOT_SPECIFIED;
1061 tcp_ao_calc_key_skb(key, traffic_key, skb, sisn, disn, family);
1062 ret = tcp_ao_verify_hash(sk, skb, family, info, aoh, key,
1063 traffic_key, phash, sne, l3index);
1064 kfree(traffic_key);
1065 return ret;
1066
1067 key_not_found:
1068 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND);
1069 atomic64_inc(&info->counters.key_not_found);
1070 trace_tcp_ao_key_not_found(sk, skb, aoh->keyid,
1071 aoh->rnext_keyid, maclen);
1072 return SKB_DROP_REASON_TCP_AOKEYNOTFOUND;
1073 }
1074
1075 static int tcp_ao_cache_traffic_keys(const struct sock *sk,
1076 struct tcp_ao_info *ao,
1077 struct tcp_ao_key *ao_key)
1078 {
1079 u8 *traffic_key = snd_other_key(ao_key);
1080 int ret;
1081
1082 ret = tcp_ao_calc_key_sk(ao_key, traffic_key, sk,
1083 ao->lisn, ao->risn, true);
1084 if (ret)
1085 return ret;
1086
1087 traffic_key = rcv_other_key(ao_key);
1088 ret = tcp_ao_calc_key_sk(ao_key, traffic_key, sk,
1089 ao->lisn, ao->risn, false);
1090 return ret;
1091 }
1092
1093 void tcp_ao_connect_init(struct sock *sk)
1094 {
1095 struct tcp_sock *tp = tcp_sk(sk);
1096 struct tcp_ao_info *ao_info;
1097 struct hlist_node *next;
1098 union tcp_ao_addr *addr;
1099 struct tcp_ao_key *key;
1100 int family, l3index;
1101
1102 ao_info = rcu_dereference_protected(tp->ao_info,
1103 lockdep_sock_is_held(sk));
1104 if (!ao_info)
1105 return;
1106
1107 /* Remove all keys that don't match the peer */
1108 family = sk->sk_family;
1109 if (family == AF_INET)
1110 addr = (union tcp_ao_addr *)&sk->sk_daddr;
1111 #if IS_ENABLED(CONFIG_IPV6)
1112 else if (family == AF_INET6)
1113 addr = (union tcp_ao_addr *)&sk->sk_v6_daddr;
1114 #endif
1115 else
1116 return;
1117 l3index = l3mdev_master_ifindex_by_index(sock_net(sk),
1118 sk->sk_bound_dev_if);
1119
1120 hlist_for_each_entry_safe(key, next, &ao_info->head, node) {
1121 if (!tcp_ao_key_cmp(key, l3index, addr, key->prefixlen, family, -1, -1))
1122 continue;
1123
1124 if (key == ao_info->current_key)
1125 ao_info->current_key = NULL;
1126 if (key == ao_info->rnext_key)
1127 ao_info->rnext_key = NULL;
1128 hlist_del_rcu(&key->node);
1129 atomic_sub(tcp_ao_sizeof_key(key), &sk->sk_omem_alloc);
1130 call_rcu(&key->rcu, tcp_ao_key_free_rcu);
1131 }
1132
1133 key = tp->af_specific->ao_lookup(sk, sk, -1, -1);
1134 if (key) {
1135 /* if current_key or rnext_key were not provided,
1136 * use the first key matching the peer
1137 */
1138 if (!ao_info->current_key)
1139 ao_info->current_key = key;
1140 if (!ao_info->rnext_key)
1141 ao_info->rnext_key = key;
1142 tp->tcp_header_len += tcp_ao_len_aligned(key);
1143
1144 ao_info->lisn = htonl(tp->write_seq);
1145 ao_info->snd_sne = 0;
1146 } else {
1147 /* Can't happen: tcp_connect() verifies that there's
1148 * at least one tcp-ao key that matches the remote peer.
1149 */
1150 WARN_ON_ONCE(1);
1151 rcu_assign_pointer(tp->ao_info, NULL);
1152 kfree(ao_info);
1153 }
1154 }
1155
1156 void tcp_ao_established(struct sock *sk)
1157 {
1158 struct tcp_ao_info *ao;
1159 struct tcp_ao_key *key;
1160
1161 ao = rcu_dereference_protected(tcp_sk(sk)->ao_info,
1162 lockdep_sock_is_held(sk));
1163 if (!ao)
1164 return;
1165
1166 hlist_for_each_entry_rcu(key, &ao->head, node)
1167 tcp_ao_cache_traffic_keys(sk, ao, key);
1168 }
1169
1170 void tcp_ao_finish_connect(struct sock *sk, struct sk_buff *skb)
1171 {
1172 struct tcp_ao_info *ao;
1173 struct tcp_ao_key *key;
1174
1175 ao = rcu_dereference_protected(tcp_sk(sk)->ao_info,
1176 lockdep_sock_is_held(sk));
1177 if (!ao)
1178 return;
1179
1180 WRITE_ONCE(ao->risn, tcp_hdr(skb)->seq);
1181 ao->rcv_sne = 0;
1182
1183 hlist_for_each_entry_rcu(key, &ao->head, node)
1184 tcp_ao_cache_traffic_keys(sk, ao, key);
1185 }
1186
1187 int tcp_ao_copy_all_matching(const struct sock *sk, struct sock *newsk,
1188 struct request_sock *req, struct sk_buff *skb,
1189 int family)
1190 {
1191 struct tcp_ao_key *key, *new_key, *first_key;
1192 struct tcp_ao_info *new_ao, *ao;
1193 struct hlist_node *key_head;
1194 int l3index, ret = -ENOMEM;
1195 union tcp_ao_addr *addr;
1196 bool match = false;
1197
1198 ao = rcu_dereference(tcp_sk(sk)->ao_info);
1199 if (!ao)
1200 return 0;
1201
1202 /* New socket without TCP-AO on it */
1203 if (!tcp_rsk_used_ao(req))
1204 return 0;
1205
1206 new_ao = tcp_ao_alloc_info(GFP_ATOMIC);
1207 if (!new_ao)
1208 return -ENOMEM;
1209 new_ao->lisn = htonl(tcp_rsk(req)->snt_isn);
1210 new_ao->risn = htonl(tcp_rsk(req)->rcv_isn);
1211 new_ao->ao_required = ao->ao_required;
1212 new_ao->accept_icmps = ao->accept_icmps;
1213
1214 if (family == AF_INET) {
1215 addr = (union tcp_ao_addr *)&newsk->sk_daddr;
1216 #if IS_ENABLED(CONFIG_IPV6)
1217 } else if (family == AF_INET6) {
1218 addr = (union tcp_ao_addr *)&newsk->sk_v6_daddr;
1219 #endif
1220 } else {
1221 ret = -EAFNOSUPPORT;
1222 goto free_ao;
1223 }
1224 l3index = l3mdev_master_ifindex_by_index(sock_net(newsk),
1225 newsk->sk_bound_dev_if);
1226
1227 hlist_for_each_entry_rcu(key, &ao->head, node) {
1228 if (tcp_ao_key_cmp(key, l3index, addr, key->prefixlen, family, -1, -1))
1229 continue;
1230
1231 new_key = tcp_ao_copy_key(newsk, key);
1232 if (!new_key)
1233 goto free_and_exit;
1234
1235 tcp_ao_cache_traffic_keys(newsk, new_ao, new_key);
1236 tcp_ao_link_mkt(new_ao, new_key);
1237 match = true;
1238 }
1239
1240 if (!match) {
1241 /* RFC5925 (7.4.1) specifies that the TCP-AO status
1242 * of a connection is determined on the initial SYN.
1243 * At this point the connection was TCP-AO enabled, so
1244 * it can't switch to being unsigned if peer's key
1245 * disappears on the listening socket.
1246 */
1247 ret = -EKEYREJECTED;
1248 goto free_and_exit;
1249 }
1250
1251 if (!static_key_fast_inc_not_disabled(&tcp_ao_needed.key.key)) {
1252 ret = -EUSERS;
1253 goto free_and_exit;
1254 }
1255
1256 key_head = rcu_dereference(hlist_first_rcu(&new_ao->head));
1257 first_key = hlist_entry_safe(key_head, struct tcp_ao_key, node);
1258
1259 key = tcp_ao_established_key(new_ao, tcp_rsk(req)->ao_keyid, -1);
1260 if (key)
1261 new_ao->current_key = key;
1262 else
1263 new_ao->current_key = first_key;
1264
1265 /* set rnext_key */
1266 key = tcp_ao_established_key(new_ao, -1, tcp_rsk(req)->ao_rcv_next);
1267 if (key)
1268 new_ao->rnext_key = key;
1269 else
1270 new_ao->rnext_key = first_key;
1271
1272 sk_gso_disable(newsk);
1273 rcu_assign_pointer(tcp_sk(newsk)->ao_info, new_ao);
1274
1275 return 0;
1276
1277 free_and_exit:
1278 hlist_for_each_entry_safe(key, key_head, &new_ao->head, node) {
1279 hlist_del(&key->node);
1280 tcp_sigpool_release(key->tcp_sigpool_id);
1281 atomic_sub(tcp_ao_sizeof_key(key), &newsk->sk_omem_alloc);
1282 kfree_sensitive(key);
1283 }
1284 free_ao:
1285 kfree(new_ao);
1286 return ret;
1287 }
1288
1289 static bool tcp_ao_can_set_current_rnext(struct sock *sk)
1290 {
1291 /* There aren't current/rnext keys on TCP_LISTEN sockets */
1292 if (sk->sk_state == TCP_LISTEN)
1293 return false;
1294 return true;
1295 }
1296
1297 static int tcp_ao_verify_ipv4(struct sock *sk, struct tcp_ao_add *cmd,
1298 union tcp_ao_addr **addr)
1299 {
1300 struct sockaddr_in *sin = (struct sockaddr_in *)&cmd->addr;
1301 struct inet_sock *inet = inet_sk(sk);
1302
1303 if (sin->sin_family != AF_INET)
1304 return -EINVAL;
1305
1306 /* Currently matching is not performed on port (or port ranges) */
1307 if (sin->sin_port != 0)
1308 return -EINVAL;
1309
1310 /* Check prefix and trailing 0's in addr */
1311 if (cmd->prefix != 0) {
1312 __be32 mask;
1313
1314 if (ntohl(sin->sin_addr.s_addr) == INADDR_ANY)
1315 return -EINVAL;
1316 if (cmd->prefix > 32)
1317 return -EINVAL;
1318
1319 mask = inet_make_mask(cmd->prefix);
1320 if (sin->sin_addr.s_addr & ~mask)
1321 return -EINVAL;
1322
1323 /* Check that MKT address is consistent with socket */
1324 if (ntohl(inet->inet_daddr) != INADDR_ANY &&
1325 (inet->inet_daddr & mask) != sin->sin_addr.s_addr)
1326 return -EINVAL;
1327 } else {
1328 if (ntohl(sin->sin_addr.s_addr) != INADDR_ANY)
1329 return -EINVAL;
1330 }
1331
1332 *addr = (union tcp_ao_addr *)&sin->sin_addr;
1333 return 0;
1334 }
1335
1336 static int tcp_ao_parse_crypto(struct tcp_ao_add *cmd, struct tcp_ao_key *key)
1337 {
1338 unsigned int syn_tcp_option_space;
1339 bool is_kdf_aes_128_cmac = false;
1340 struct crypto_ahash *tfm;
1341 struct tcp_sigpool hp;
1342 void *tmp_key = NULL;
1343 int err;
1344
1345 /* RFC5926, 3.1.1.2. KDF_AES_128_CMAC */
1346 if (!strcmp("cmac(aes128)", cmd->alg_name)) {
1347 strscpy(cmd->alg_name, "cmac(aes)", sizeof(cmd->alg_name));
1348 is_kdf_aes_128_cmac = (cmd->keylen != 16);
1349 tmp_key = kmalloc(cmd->keylen, GFP_KERNEL);
1350 if (!tmp_key)
1351 return -ENOMEM;
1352 }
1353
1354 key->maclen = cmd->maclen ?: 12; /* 12 is the default in RFC5925 */
1355
1356 /* Check: maclen + tcp-ao header <= (MAX_TCP_OPTION_SPACE - mss
1357 * - tstamp (including sackperm)
1358 * - wscale),
1359 * see tcp_syn_options(), tcp_synack_options(), commit 33ad798c924b.
1360 *
1361 * In order to allow D-SACK with TCP-AO, the header size should be:
1362 * (MAX_TCP_OPTION_SPACE - TCPOLEN_TSTAMP_ALIGNED
1363 * - TCPOLEN_SACK_BASE_ALIGNED
1364 * - 2 * TCPOLEN_SACK_PERBLOCK) = 8 (maclen = 4),
1365 * see tcp_established_options().
1366 *
1367 * RFC5925, 2.2:
1368 * Typical MACs are 96-128 bits (12-16 bytes), but any length
1369 * that fits in the header of the segment being authenticated
1370 * is allowed.
1371 *
1372 * RFC5925, 7.6:
1373 * TCP-AO continues to consume 16 bytes in non-SYN segments,
1374 * leaving a total of 24 bytes for other options, of which
1375 * the timestamp consumes 10. This leaves 14 bytes, of which 10
1376 * are used for a single SACK block. When two SACK blocks are used,
1377 * such as to handle D-SACK, a smaller TCP-AO MAC would be required
1378 * to make room for the additional SACK block (i.e., to leave 18
1379 * bytes for the D-SACK variant of the SACK option) [RFC2883].
1380 * Note that D-SACK is not supportable in TCP MD5 in the presence
1381 * of timestamps, because TCP MD5’s MAC length is fixed and too
1382 * large to leave sufficient option space.
1383 */
1384 syn_tcp_option_space = MAX_TCP_OPTION_SPACE;
1385 syn_tcp_option_space -= TCPOLEN_MSS_ALIGNED;
1386 syn_tcp_option_space -= TCPOLEN_TSTAMP_ALIGNED;
1387 syn_tcp_option_space -= TCPOLEN_WSCALE_ALIGNED;
1388 if (tcp_ao_len_aligned(key) > syn_tcp_option_space) {
1389 err = -EMSGSIZE;
1390 goto err_kfree;
1391 }
1392
1393 key->keylen = cmd->keylen;
1394 memcpy(key->key, cmd->key, cmd->keylen);
1395
1396 err = tcp_sigpool_start(key->tcp_sigpool_id, &hp);
1397 if (err)
1398 goto err_kfree;
1399
1400 tfm = crypto_ahash_reqtfm(hp.req);
1401 if (is_kdf_aes_128_cmac) {
1402 void *scratch = hp.scratch;
1403 struct scatterlist sg;
1404
1405 memcpy(tmp_key, cmd->key, cmd->keylen);
1406 sg_init_one(&sg, tmp_key, cmd->keylen);
1407
1408 /* Using zero-key of 16 bytes as described in RFC5926 */
1409 memset(scratch, 0, 16);
1410 err = crypto_ahash_setkey(tfm, scratch, 16);
1411 if (err)
1412 goto err_pool_end;
1413
1414 err = crypto_ahash_init(hp.req);
1415 if (err)
1416 goto err_pool_end;
1417
1418 ahash_request_set_crypt(hp.req, &sg, key->key, cmd->keylen);
1419 err = crypto_ahash_update(hp.req);
1420 if (err)
1421 goto err_pool_end;
1422
1423 err |= crypto_ahash_final(hp.req);
1424 if (err)
1425 goto err_pool_end;
1426 key->keylen = 16;
1427 }
1428
1429 err = crypto_ahash_setkey(tfm, key->key, key->keylen);
1430 if (err)
1431 goto err_pool_end;
1432
1433 tcp_sigpool_end(&hp);
1434 kfree_sensitive(tmp_key);
1435
1436 if (tcp_ao_maclen(key) > key->digest_size)
1437 return -EINVAL;
1438
1439 return 0;
1440
1441 err_pool_end:
1442 tcp_sigpool_end(&hp);
1443 err_kfree:
1444 kfree_sensitive(tmp_key);
1445 return err;
1446 }
1447
1448 #if IS_ENABLED(CONFIG_IPV6)
1449 static int tcp_ao_verify_ipv6(struct sock *sk, struct tcp_ao_add *cmd,
1450 union tcp_ao_addr **paddr,
1451 unsigned short int *family)
1452 {
1453 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd->addr;
1454 struct in6_addr *addr = &sin6->sin6_addr;
1455 u8 prefix = cmd->prefix;
1456
1457 if (sin6->sin6_family != AF_INET6)
1458 return -EINVAL;
1459
1460 /* Currently matching is not performed on port (or port ranges) */
1461 if (sin6->sin6_port != 0)
1462 return -EINVAL;
1463
1464 /* Check prefix and trailing 0's in addr */
1465 if (cmd->prefix != 0 && ipv6_addr_v4mapped(addr)) {
1466 __be32 addr4 = addr->s6_addr32[3];
1467 __be32 mask;
1468
1469 if (prefix > 32 || ntohl(addr4) == INADDR_ANY)
1470 return -EINVAL;
1471
1472 mask = inet_make_mask(prefix);
1473 if (addr4 & ~mask)
1474 return -EINVAL;
1475
1476 /* Check that MKT address is consistent with socket */
1477 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
1478 __be32 daddr4 = sk->sk_v6_daddr.s6_addr32[3];
1479
1480 if (!ipv6_addr_v4mapped(&sk->sk_v6_daddr))
1481 return -EINVAL;
1482 if ((daddr4 & mask) != addr4)
1483 return -EINVAL;
1484 }
1485
1486 *paddr = (union tcp_ao_addr *)&addr->s6_addr32[3];
1487 *family = AF_INET;
1488 return 0;
1489 } else if (cmd->prefix != 0) {
1490 struct in6_addr pfx;
1491
1492 if (ipv6_addr_any(addr) || prefix > 128)
1493 return -EINVAL;
1494
1495 ipv6_addr_prefix(&pfx, addr, prefix);
1496 if (ipv6_addr_cmp(&pfx, addr))
1497 return -EINVAL;
1498
1499 /* Check that MKT address is consistent with socket */
1500 if (!ipv6_addr_any(&sk->sk_v6_daddr) &&
1501 !ipv6_prefix_equal(&sk->sk_v6_daddr, addr, prefix))
1502
1503 return -EINVAL;
1504 } else {
1505 if (!ipv6_addr_any(addr))
1506 return -EINVAL;
1507 }
1508
1509 *paddr = (union tcp_ao_addr *)addr;
1510 return 0;
1511 }
1512 #else
1513 static int tcp_ao_verify_ipv6(struct sock *sk, struct tcp_ao_add *cmd,
1514 union tcp_ao_addr **paddr,
1515 unsigned short int *family)
1516 {
1517 return -EOPNOTSUPP;
1518 }
1519 #endif
1520
1521 static struct tcp_ao_info *setsockopt_ao_info(struct sock *sk)
1522 {
1523 if (sk_fullsock(sk)) {
1524 return rcu_dereference_protected(tcp_sk(sk)->ao_info,
1525 lockdep_sock_is_held(sk));
1526 } else if (sk->sk_state == TCP_TIME_WAIT) {
1527 return rcu_dereference_protected(tcp_twsk(sk)->ao_info,
1528 lockdep_sock_is_held(sk));
1529 }
1530 return ERR_PTR(-ESOCKTNOSUPPORT);
1531 }
1532
1533 static struct tcp_ao_info *getsockopt_ao_info(struct sock *sk)
1534 {
1535 if (sk_fullsock(sk))
1536 return rcu_dereference(tcp_sk(sk)->ao_info);
1537 else if (sk->sk_state == TCP_TIME_WAIT)
1538 return rcu_dereference(tcp_twsk(sk)->ao_info);
1539
1540 return ERR_PTR(-ESOCKTNOSUPPORT);
1541 }
1542
1543 #define TCP_AO_KEYF_ALL (TCP_AO_KEYF_IFINDEX | TCP_AO_KEYF_EXCLUDE_OPT)
1544 #define TCP_AO_GET_KEYF_VALID (TCP_AO_KEYF_IFINDEX)
1545
1546 static struct tcp_ao_key *tcp_ao_key_alloc(struct sock *sk,
1547 struct tcp_ao_add *cmd)
1548 {
1549 const char *algo = cmd->alg_name;
1550 unsigned int digest_size;
1551 struct crypto_ahash *tfm;
1552 struct tcp_ao_key *key;
1553 struct tcp_sigpool hp;
1554 int err, pool_id;
1555 size_t size;
1556
1557 /* Force null-termination of alg_name */
1558 cmd->alg_name[ARRAY_SIZE(cmd->alg_name) - 1] = '\0';
1559
1560 /* RFC5926, 3.1.1.2. KDF_AES_128_CMAC */
1561 if (!strcmp("cmac(aes128)", algo))
1562 algo = "cmac(aes)";
1563
1564 /* Full TCP header (th->doff << 2) should fit into scratch area,
1565 * see tcp_ao_hash_header().
1566 */
1567 pool_id = tcp_sigpool_alloc_ahash(algo, 60);
1568 if (pool_id < 0)
1569 return ERR_PTR(pool_id);
1570
1571 err = tcp_sigpool_start(pool_id, &hp);
1572 if (err)
1573 goto err_free_pool;
1574
1575 tfm = crypto_ahash_reqtfm(hp.req);
1576 digest_size = crypto_ahash_digestsize(tfm);
1577 tcp_sigpool_end(&hp);
1578
1579 size = sizeof(struct tcp_ao_key) + (digest_size << 1);
1580 key = sock_kmalloc(sk, size, GFP_KERNEL);
1581 if (!key) {
1582 err = -ENOMEM;
1583 goto err_free_pool;
1584 }
1585
1586 key->tcp_sigpool_id = pool_id;
1587 key->digest_size = digest_size;
1588 return key;
1589
1590 err_free_pool:
1591 tcp_sigpool_release(pool_id);
1592 return ERR_PTR(err);
1593 }
1594
1595 static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family,
1596 sockptr_t optval, int optlen)
1597 {
1598 struct tcp_ao_info *ao_info;
1599 union tcp_ao_addr *addr;
1600 struct tcp_ao_key *key;
1601 struct tcp_ao_add cmd;
1602 int ret, l3index = 0;
1603 bool first = false;
1604
1605 if (optlen < sizeof(cmd))
1606 return -EINVAL;
1607
1608 ret = copy_struct_from_sockptr(&cmd, sizeof(cmd), optval, optlen);
1609 if (ret)
1610 return ret;
1611
1612 if (cmd.keylen > TCP_AO_MAXKEYLEN)
1613 return -EINVAL;
1614
1615 if (cmd.reserved != 0 || cmd.reserved2 != 0)
1616 return -EINVAL;
1617
1618 if (family == AF_INET)
1619 ret = tcp_ao_verify_ipv4(sk, &cmd, &addr);
1620 else
1621 ret = tcp_ao_verify_ipv6(sk, &cmd, &addr, &family);
1622 if (ret)
1623 return ret;
1624
1625 if (cmd.keyflags & ~TCP_AO_KEYF_ALL)
1626 return -EINVAL;
1627
1628 if (cmd.set_current || cmd.set_rnext) {
1629 if (!tcp_ao_can_set_current_rnext(sk))
1630 return -EINVAL;
1631 }
1632
1633 if (cmd.ifindex && !(cmd.keyflags & TCP_AO_KEYF_IFINDEX))
1634 return -EINVAL;
1635
1636 /* For cmd.tcp_ifindex = 0 the key will apply to the default VRF */
1637 if (cmd.keyflags & TCP_AO_KEYF_IFINDEX && cmd.ifindex) {
1638 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
1639 struct net_device *dev;
1640
1641 rcu_read_lock();
1642 dev = dev_get_by_index_rcu(sock_net(sk), cmd.ifindex);
1643 if (dev && netif_is_l3_master(dev))
1644 l3index = dev->ifindex;
1645 rcu_read_unlock();
1646
1647 if (!dev || !l3index)
1648 return -EINVAL;
1649
1650 if (!bound_dev_if || bound_dev_if != cmd.ifindex) {
1651 /* tcp_ao_established_key() doesn't expect having
1652 * non peer-matching key on an established TCP-AO
1653 * connection.
1654 */
1655 if (!((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)))
1656 return -EINVAL;
1657 }
1658
1659 /* It's still possible to bind after adding keys or even
1660 * re-bind to a different dev (with CAP_NET_RAW).
1661 * So, no reason to return error here, rather try to be
1662 * nice and warn the user.
1663 */
1664 if (bound_dev_if && bound_dev_if != cmd.ifindex)
1665 net_warn_ratelimited("AO key ifindex %d != sk bound ifindex %d\n",
1666 cmd.ifindex, bound_dev_if);
1667 }
1668
1669 /* Don't allow keys for peers that have a matching TCP-MD5 key */
1670 if (cmd.keyflags & TCP_AO_KEYF_IFINDEX) {
1671 /* Non-_exact version of tcp_md5_do_lookup() will
1672 * as well match keys that aren't bound to a specific VRF
1673 * (that will make them match AO key with
1674 * sysctl_tcp_l3dev_accept = 1
1675 */
1676 if (tcp_md5_do_lookup(sk, l3index, addr, family))
1677 return -EKEYREJECTED;
1678 } else {
1679 if (tcp_md5_do_lookup_any_l3index(sk, addr, family))
1680 return -EKEYREJECTED;
1681 }
1682
1683 ao_info = setsockopt_ao_info(sk);
1684 if (IS_ERR(ao_info))
1685 return PTR_ERR(ao_info);
1686
1687 if (!ao_info) {
1688 ao_info = tcp_ao_alloc_info(GFP_KERNEL);
1689 if (!ao_info)
1690 return -ENOMEM;
1691 first = true;
1692 } else {
1693 /* Check that neither RecvID nor SendID match any
1694 * existing key for the peer, RFC5925 3.1:
1695 * > The IDs of MKTs MUST NOT overlap where their
1696 * > TCP connection identifiers overlap.
1697 */
1698 if (__tcp_ao_do_lookup(sk, l3index, addr, family, cmd.prefix, -1, cmd.rcvid))
1699 return -EEXIST;
1700 if (__tcp_ao_do_lookup(sk, l3index, addr, family,
1701 cmd.prefix, cmd.sndid, -1))
1702 return -EEXIST;
1703 }
1704
1705 key = tcp_ao_key_alloc(sk, &cmd);
1706 if (IS_ERR(key)) {
1707 ret = PTR_ERR(key);
1708 goto err_free_ao;
1709 }
1710
1711 INIT_HLIST_NODE(&key->node);
1712 memcpy(&key->addr, addr, (family == AF_INET) ? sizeof(struct in_addr) :
1713 sizeof(struct in6_addr));
1714 key->prefixlen = cmd.prefix;
1715 key->family = family;
1716 key->keyflags = cmd.keyflags;
1717 key->sndid = cmd.sndid;
1718 key->rcvid = cmd.rcvid;
1719 key->l3index = l3index;
1720 atomic64_set(&key->pkt_good, 0);
1721 atomic64_set(&key->pkt_bad, 0);
1722
1723 ret = tcp_ao_parse_crypto(&cmd, key);
1724 if (ret < 0)
1725 goto err_free_sock;
1726
1727 if (!((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))) {
1728 tcp_ao_cache_traffic_keys(sk, ao_info, key);
1729 if (first) {
1730 ao_info->current_key = key;
1731 ao_info->rnext_key = key;
1732 }
1733 }
1734
1735 tcp_ao_link_mkt(ao_info, key);
1736 if (first) {
1737 if (!static_branch_inc(&tcp_ao_needed.key)) {
1738 ret = -EUSERS;
1739 goto err_free_sock;
1740 }
1741 sk_gso_disable(sk);
1742 rcu_assign_pointer(tcp_sk(sk)->ao_info, ao_info);
1743 }
1744
1745 if (cmd.set_current)
1746 WRITE_ONCE(ao_info->current_key, key);
1747 if (cmd.set_rnext)
1748 WRITE_ONCE(ao_info->rnext_key, key);
1749 return 0;
1750
1751 err_free_sock:
1752 atomic_sub(tcp_ao_sizeof_key(key), &sk->sk_omem_alloc);
1753 tcp_sigpool_release(key->tcp_sigpool_id);
1754 kfree_sensitive(key);
1755 err_free_ao:
1756 if (first)
1757 kfree(ao_info);
1758 return ret;
1759 }
1760
1761 static int tcp_ao_delete_key(struct sock *sk, struct tcp_ao_info *ao_info,
1762 bool del_async, struct tcp_ao_key *key,
1763 struct tcp_ao_key *new_current,
1764 struct tcp_ao_key *new_rnext)
1765 {
1766 int err;
1767
1768 hlist_del_rcu(&key->node);
1769
1770 /* Support for async delete on listening sockets: as they don't
1771 * need current_key/rnext_key maintaining, we don't need to check
1772 * them and we can just free all resources in RCU fashion.
1773 */
1774 if (del_async) {
1775 atomic_sub(tcp_ao_sizeof_key(key), &sk->sk_omem_alloc);
1776 call_rcu(&key->rcu, tcp_ao_key_free_rcu);
1777 return 0;
1778 }
1779
1780 /* At this moment another CPU could have looked this key up
1781 * while it was unlinked from the list. Wait for RCU grace period,
1782 * after which the key is off-list and can't be looked up again;
1783 * the rx path [just before RCU came] might have used it and set it
1784 * as current_key (very unlikely).
1785 * Free the key with next RCU grace period (in case it was
1786 * current_key before tcp_ao_current_rnext() might have
1787 * changed it in forced-delete).
1788 */
1789 synchronize_rcu();
1790 if (new_current)
1791 WRITE_ONCE(ao_info->current_key, new_current);
1792 if (new_rnext)
1793 WRITE_ONCE(ao_info->rnext_key, new_rnext);
1794
1795 if (unlikely(READ_ONCE(ao_info->current_key) == key ||
1796 READ_ONCE(ao_info->rnext_key) == key)) {
1797 err = -EBUSY;
1798 goto add_key;
1799 }
1800
1801 atomic_sub(tcp_ao_sizeof_key(key), &sk->sk_omem_alloc);
1802 call_rcu(&key->rcu, tcp_ao_key_free_rcu);
1803
1804 return 0;
1805 add_key:
1806 hlist_add_head_rcu(&key->node, &ao_info->head);
1807 return err;
1808 }
1809
1810 #define TCP_AO_DEL_KEYF_ALL (TCP_AO_KEYF_IFINDEX)
1811 static int tcp_ao_del_cmd(struct sock *sk, unsigned short int family,
1812 sockptr_t optval, int optlen)
1813 {
1814 struct tcp_ao_key *key, *new_current = NULL, *new_rnext = NULL;
1815 int err, addr_len, l3index = 0;
1816 struct tcp_ao_info *ao_info;
1817 union tcp_ao_addr *addr;
1818 struct tcp_ao_del cmd;
1819 __u8 prefix;
1820 u16 port;
1821
1822 if (optlen < sizeof(cmd))
1823 return -EINVAL;
1824
1825 err = copy_struct_from_sockptr(&cmd, sizeof(cmd), optval, optlen);
1826 if (err)
1827 return err;
1828
1829 if (cmd.reserved != 0 || cmd.reserved2 != 0)
1830 return -EINVAL;
1831
1832 if (cmd.set_current || cmd.set_rnext) {
1833 if (!tcp_ao_can_set_current_rnext(sk))
1834 return -EINVAL;
1835 }
1836
1837 if (cmd.keyflags & ~TCP_AO_DEL_KEYF_ALL)
1838 return -EINVAL;
1839
1840 /* No sanity check for TCP_AO_KEYF_IFINDEX as if a VRF
1841 * was destroyed, there still should be a way to delete keys,
1842 * that were bound to that l3intf. So, fail late at lookup stage
1843 * if there is no key for that ifindex.
1844 */
1845 if (cmd.ifindex && !(cmd.keyflags & TCP_AO_KEYF_IFINDEX))
1846 return -EINVAL;
1847
1848 ao_info = setsockopt_ao_info(sk);
1849 if (IS_ERR(ao_info))
1850 return PTR_ERR(ao_info);
1851 if (!ao_info)
1852 return -ENOENT;
1853
1854 /* For sockets in TCP_CLOSED it's possible set keys that aren't
1855 * matching the future peer (address/VRF/etc),
1856 * tcp_ao_connect_init() will choose a correct matching MKT
1857 * if there's any.
1858 */
1859 if (cmd.set_current) {
1860 new_current = tcp_ao_established_key(ao_info, cmd.current_key, -1);
1861 if (!new_current)
1862 return -ENOENT;
1863 }
1864 if (cmd.set_rnext) {
1865 new_rnext = tcp_ao_established_key(ao_info, -1, cmd.rnext);
1866 if (!new_rnext)
1867 return -ENOENT;
1868 }
1869 if (cmd.del_async && sk->sk_state != TCP_LISTEN)
1870 return -EINVAL;
1871
1872 if (family == AF_INET) {
1873 struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.addr;
1874
1875 addr = (union tcp_ao_addr *)&sin->sin_addr;
1876 addr_len = sizeof(struct in_addr);
1877 port = ntohs(sin->sin_port);
1878 } else {
1879 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.addr;
1880 struct in6_addr *addr6 = &sin6->sin6_addr;
1881
1882 if (ipv6_addr_v4mapped(addr6)) {
1883 addr = (union tcp_ao_addr *)&addr6->s6_addr32[3];
1884 addr_len = sizeof(struct in_addr);
1885 family = AF_INET;
1886 } else {
1887 addr = (union tcp_ao_addr *)addr6;
1888 addr_len = sizeof(struct in6_addr);
1889 }
1890 port = ntohs(sin6->sin6_port);
1891 }
1892 prefix = cmd.prefix;
1893
1894 /* Currently matching is not performed on port (or port ranges) */
1895 if (port != 0)
1896 return -EINVAL;
1897
1898 /* We could choose random present key here for current/rnext
1899 * but that's less predictable. Let's be strict and don't
1900 * allow removing a key that's in use. RFC5925 doesn't
1901 * specify how-to coordinate key removal, but says:
1902 * "It is presumed that an MKT affecting a particular
1903 * connection cannot be destroyed during an active connection"
1904 */
1905 hlist_for_each_entry_rcu(key, &ao_info->head, node) {
1906 if (cmd.sndid != key->sndid ||
1907 cmd.rcvid != key->rcvid)
1908 continue;
1909
1910 if (family != key->family ||
1911 prefix != key->prefixlen ||
1912 memcmp(addr, &key->addr, addr_len))
1913 continue;
1914
1915 if ((cmd.keyflags & TCP_AO_KEYF_IFINDEX) !=
1916 (key->keyflags & TCP_AO_KEYF_IFINDEX))
1917 continue;
1918
1919 if (key->l3index != l3index)
1920 continue;
1921
1922 if (key == new_current || key == new_rnext)
1923 continue;
1924
1925 return tcp_ao_delete_key(sk, ao_info, cmd.del_async, key,
1926 new_current, new_rnext);
1927 }
1928 return -ENOENT;
1929 }
1930
1931 /* cmd.ao_required makes a socket TCP-AO only.
1932 * Don't allow any md5 keys for any l3intf on the socket together with it.
1933 * Restricting it early in setsockopt() removes a check for
1934 * ao_info->ao_required on inbound tcp segment fast-path.
1935 */
1936 static int tcp_ao_required_verify(struct sock *sk)
1937 {
1938 #ifdef CONFIG_TCP_MD5SIG
1939 const struct tcp_md5sig_info *md5sig;
1940
1941 if (!static_branch_unlikely(&tcp_md5_needed.key))
1942 return 0;
1943
1944 md5sig = rcu_dereference_check(tcp_sk(sk)->md5sig_info,
1945 lockdep_sock_is_held(sk));
1946 if (!md5sig)
1947 return 0;
1948
1949 if (rcu_dereference_check(hlist_first_rcu(&md5sig->head),
1950 lockdep_sock_is_held(sk)))
1951 return 1;
1952 #endif
1953 return 0;
1954 }
1955
1956 static int tcp_ao_info_cmd(struct sock *sk, unsigned short int family,
1957 sockptr_t optval, int optlen)
1958 {
1959 struct tcp_ao_key *new_current = NULL, *new_rnext = NULL;
1960 struct tcp_ao_info *ao_info;
1961 struct tcp_ao_info_opt cmd;
1962 bool first = false;
1963 int err;
1964
1965 if (optlen < sizeof(cmd))
1966 return -EINVAL;
1967
1968 err = copy_struct_from_sockptr(&cmd, sizeof(cmd), optval, optlen);
1969 if (err)
1970 return err;
1971
1972 if (cmd.set_current || cmd.set_rnext) {
1973 if (!tcp_ao_can_set_current_rnext(sk))
1974 return -EINVAL;
1975 }
1976
1977 if (cmd.reserved != 0 || cmd.reserved2 != 0)
1978 return -EINVAL;
1979
1980 ao_info = setsockopt_ao_info(sk);
1981 if (IS_ERR(ao_info))
1982 return PTR_ERR(ao_info);
1983 if (!ao_info) {
1984 if (!((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)))
1985 return -EINVAL;
1986 ao_info = tcp_ao_alloc_info(GFP_KERNEL);
1987 if (!ao_info)
1988 return -ENOMEM;
1989 first = true;
1990 }
1991
1992 if (cmd.ao_required && tcp_ao_required_verify(sk)) {
1993 err = -EKEYREJECTED;
1994 goto out;
1995 }
1996
1997 /* For sockets in TCP_CLOSED it's possible set keys that aren't
1998 * matching the future peer (address/port/VRF/etc),
1999 * tcp_ao_connect_init() will choose a correct matching MKT
2000 * if there's any.
2001 */
2002 if (cmd.set_current) {
2003 new_current = tcp_ao_established_key(ao_info, cmd.current_key, -1);
2004 if (!new_current) {
2005 err = -ENOENT;
2006 goto out;
2007 }
2008 }
2009 if (cmd.set_rnext) {
2010 new_rnext = tcp_ao_established_key(ao_info, -1, cmd.rnext);
2011 if (!new_rnext) {
2012 err = -ENOENT;
2013 goto out;
2014 }
2015 }
2016 if (cmd.set_counters) {
2017 atomic64_set(&ao_info->counters.pkt_good, cmd.pkt_good);
2018 atomic64_set(&ao_info->counters.pkt_bad, cmd.pkt_bad);
2019 atomic64_set(&ao_info->counters.key_not_found, cmd.pkt_key_not_found);
2020 atomic64_set(&ao_info->counters.ao_required, cmd.pkt_ao_required);
2021 atomic64_set(&ao_info->counters.dropped_icmp, cmd.pkt_dropped_icmp);
2022 }
2023
2024 ao_info->ao_required = cmd.ao_required;
2025 ao_info->accept_icmps = cmd.accept_icmps;
2026 if (new_current)
2027 WRITE_ONCE(ao_info->current_key, new_current);
2028 if (new_rnext)
2029 WRITE_ONCE(ao_info->rnext_key, new_rnext);
2030 if (first) {
2031 if (!static_branch_inc(&tcp_ao_needed.key)) {
2032 err = -EUSERS;
2033 goto out;
2034 }
2035 sk_gso_disable(sk);
2036 rcu_assign_pointer(tcp_sk(sk)->ao_info, ao_info);
2037 }
2038 return 0;
2039 out:
2040 if (first)
2041 kfree(ao_info);
2042 return err;
2043 }
2044
2045 int tcp_parse_ao(struct sock *sk, int cmd, unsigned short int family,
2046 sockptr_t optval, int optlen)
2047 {
2048 if (WARN_ON_ONCE(family != AF_INET && family != AF_INET6))
2049 return -EAFNOSUPPORT;
2050
2051 switch (cmd) {
2052 case TCP_AO_ADD_KEY:
2053 return tcp_ao_add_cmd(sk, family, optval, optlen);
2054 case TCP_AO_DEL_KEY:
2055 return tcp_ao_del_cmd(sk, family, optval, optlen);
2056 case TCP_AO_INFO:
2057 return tcp_ao_info_cmd(sk, family, optval, optlen);
2058 default:
2059 WARN_ON_ONCE(1);
2060 return -EINVAL;
2061 }
2062 }
2063
2064 int tcp_v4_parse_ao(struct sock *sk, int cmd, sockptr_t optval, int optlen)
2065 {
2066 return tcp_parse_ao(sk, cmd, AF_INET, optval, optlen);
2067 }
2068
2069 /* tcp_ao_copy_mkts_to_user(ao_info, optval, optlen)
2070 *
2071 * @ao_info: struct tcp_ao_info on the socket that
2072 * socket getsockopt(TCP_AO_GET_KEYS) is executed on
2073 * @optval: pointer to array of tcp_ao_getsockopt structures in user space.
2074 * Must be != NULL.
2075 * @optlen: pointer to size of tcp_ao_getsockopt structure.
2076 * Must be != NULL.
2077 *
2078 * Return value: 0 on success, a negative error number otherwise.
2079 *
2080 * optval points to an array of tcp_ao_getsockopt structures in user space.
2081 * optval[0] is used as both input and output to getsockopt. It determines
2082 * which keys are returned by the kernel.
2083 * optval[0].nkeys is the size of the array in user space. On return it contains
2084 * the number of keys matching the search criteria.
2085 * If tcp_ao_getsockopt::get_all is set, then all keys in the socket are
2086 * returned, otherwise only keys matching <addr, prefix, sndid, rcvid>
2087 * in optval[0] are returned.
2088 * optlen is also used as both input and output. The user provides the size
2089 * of struct tcp_ao_getsockopt in user space, and the kernel returns the size
2090 * of the structure in kernel space.
2091 * The size of struct tcp_ao_getsockopt may differ between user and kernel.
2092 * There are three cases to consider:
2093 * * If usize == ksize, then keys are copied verbatim.
2094 * * If usize < ksize, then the userspace has passed an old struct to a
2095 * newer kernel. The rest of the trailing bytes in optval[0]
2096 * (ksize - usize) are interpreted as 0 by the kernel.
2097 * * If usize > ksize, then the userspace has passed a new struct to an
2098 * older kernel. The trailing bytes unknown to the kernel (usize - ksize)
2099 * are checked to ensure they are zeroed, otherwise -E2BIG is returned.
2100 * On return the kernel fills in min(usize, ksize) in each entry of the array.
2101 * The layout of the fields in the user and kernel structures is expected to
2102 * be the same (including in the 32bit vs 64bit case).
2103 */
2104 static int tcp_ao_copy_mkts_to_user(struct tcp_ao_info *ao_info,
2105 sockptr_t optval, sockptr_t optlen)
2106 {
2107 struct tcp_ao_getsockopt opt_in, opt_out;
2108 struct tcp_ao_key *key, *current_key;
2109 bool do_address_matching = true;
2110 union tcp_ao_addr *addr = NULL;
2111 int err, l3index, user_len;
2112 unsigned int max_keys; /* maximum number of keys to copy to user */
2113 size_t out_offset = 0;
2114 size_t bytes_to_write; /* number of bytes to write to user level */
2115 u32 matched_keys; /* keys from ao_info matched so far */
2116 int optlen_out;
2117 __be16 port = 0;
2118
2119 if (copy_from_sockptr(&user_len, optlen, sizeof(int)))
2120 return -EFAULT;
2121
2122 if (user_len <= 0)
2123 return -EINVAL;
2124
2125 memset(&opt_in, 0, sizeof(struct tcp_ao_getsockopt));
2126 err = copy_struct_from_sockptr(&opt_in, sizeof(opt_in),
2127 optval, user_len);
2128 if (err < 0)
2129 return err;
2130
2131 if (opt_in.pkt_good || opt_in.pkt_bad)
2132 return -EINVAL;
2133 if (opt_in.keyflags & ~TCP_AO_GET_KEYF_VALID)
2134 return -EINVAL;
2135 if (opt_in.ifindex && !(opt_in.keyflags & TCP_AO_KEYF_IFINDEX))
2136 return -EINVAL;
2137
2138 if (opt_in.reserved != 0)
2139 return -EINVAL;
2140
2141 max_keys = opt_in.nkeys;
2142 l3index = (opt_in.keyflags & TCP_AO_KEYF_IFINDEX) ? opt_in.ifindex : -1;
2143
2144 if (opt_in.get_all || opt_in.is_current || opt_in.is_rnext) {
2145 if (opt_in.get_all && (opt_in.is_current || opt_in.is_rnext))
2146 return -EINVAL;
2147 do_address_matching = false;
2148 }
2149
2150 switch (opt_in.addr.ss_family) {
2151 case AF_INET: {
2152 struct sockaddr_in *sin;
2153 __be32 mask;
2154
2155 sin = (struct sockaddr_in *)&opt_in.addr;
2156 port = sin->sin_port;
2157 addr = (union tcp_ao_addr *)&sin->sin_addr;
2158
2159 if (opt_in.prefix > 32)
2160 return -EINVAL;
2161
2162 if (ntohl(sin->sin_addr.s_addr) == INADDR_ANY &&
2163 opt_in.prefix != 0)
2164 return -EINVAL;
2165
2166 mask = inet_make_mask(opt_in.prefix);
2167 if (sin->sin_addr.s_addr & ~mask)
2168 return -EINVAL;
2169
2170 break;
2171 }
2172 case AF_INET6: {
2173 struct sockaddr_in6 *sin6;
2174 struct in6_addr *addr6;
2175
2176 sin6 = (struct sockaddr_in6 *)&opt_in.addr;
2177 addr = (union tcp_ao_addr *)&sin6->sin6_addr;
2178 addr6 = &sin6->sin6_addr;
2179 port = sin6->sin6_port;
2180
2181 /* We don't have to change family and @addr here if
2182 * ipv6_addr_v4mapped() like in key adding:
2183 * tcp_ao_key_cmp() does it. Do the sanity checks though.
2184 */
2185 if (opt_in.prefix != 0) {
2186 if (ipv6_addr_v4mapped(addr6)) {
2187 __be32 mask, addr4 = addr6->s6_addr32[3];
2188
2189 if (opt_in.prefix > 32 ||
2190 ntohl(addr4) == INADDR_ANY)
2191 return -EINVAL;
2192 mask = inet_make_mask(opt_in.prefix);
2193 if (addr4 & ~mask)
2194 return -EINVAL;
2195 } else {
2196 struct in6_addr pfx;
2197
2198 if (ipv6_addr_any(addr6) ||
2199 opt_in.prefix > 128)
2200 return -EINVAL;
2201
2202 ipv6_addr_prefix(&pfx, addr6, opt_in.prefix);
2203 if (ipv6_addr_cmp(&pfx, addr6))
2204 return -EINVAL;
2205 }
2206 } else if (!ipv6_addr_any(addr6)) {
2207 return -EINVAL;
2208 }
2209 break;
2210 }
2211 case 0:
2212 if (!do_address_matching)
2213 break;
2214 fallthrough;
2215 default:
2216 return -EAFNOSUPPORT;
2217 }
2218
2219 if (!do_address_matching) {
2220 /* We could just ignore those, but let's do stricter checks */
2221 if (addr || port)
2222 return -EINVAL;
2223 if (opt_in.prefix || opt_in.sndid || opt_in.rcvid)
2224 return -EINVAL;
2225 }
2226
2227 bytes_to_write = min_t(int, user_len, sizeof(struct tcp_ao_getsockopt));
2228 matched_keys = 0;
2229 /* May change in RX, while we're dumping, pre-fetch it */
2230 current_key = READ_ONCE(ao_info->current_key);
2231
2232 hlist_for_each_entry_rcu(key, &ao_info->head, node) {
2233 if (opt_in.get_all)
2234 goto match;
2235
2236 if (opt_in.is_current || opt_in.is_rnext) {
2237 if (opt_in.is_current && key == current_key)
2238 goto match;
2239 if (opt_in.is_rnext && key == ao_info->rnext_key)
2240 goto match;
2241 continue;
2242 }
2243
2244 if (tcp_ao_key_cmp(key, l3index, addr, opt_in.prefix,
2245 opt_in.addr.ss_family,
2246 opt_in.sndid, opt_in.rcvid) != 0)
2247 continue;
2248 match:
2249 matched_keys++;
2250 if (matched_keys > max_keys)
2251 continue;
2252
2253 memset(&opt_out, 0, sizeof(struct tcp_ao_getsockopt));
2254
2255 if (key->family == AF_INET) {
2256 struct sockaddr_in *sin_out = (struct sockaddr_in *)&opt_out.addr;
2257
2258 sin_out->sin_family = key->family;
2259 sin_out->sin_port = 0;
2260 memcpy(&sin_out->sin_addr, &key->addr, sizeof(struct in_addr));
2261 } else {
2262 struct sockaddr_in6 *sin6_out = (struct sockaddr_in6 *)&opt_out.addr;
2263
2264 sin6_out->sin6_family = key->family;
2265 sin6_out->sin6_port = 0;
2266 memcpy(&sin6_out->sin6_addr, &key->addr, sizeof(struct in6_addr));
2267 }
2268 opt_out.sndid = key->sndid;
2269 opt_out.rcvid = key->rcvid;
2270 opt_out.prefix = key->prefixlen;
2271 opt_out.keyflags = key->keyflags;
2272 opt_out.is_current = (key == current_key);
2273 opt_out.is_rnext = (key == ao_info->rnext_key);
2274 opt_out.nkeys = 0;
2275 opt_out.maclen = key->maclen;
2276 opt_out.keylen = key->keylen;
2277 opt_out.ifindex = key->l3index;
2278 opt_out.pkt_good = atomic64_read(&key->pkt_good);
2279 opt_out.pkt_bad = atomic64_read(&key->pkt_bad);
2280 memcpy(&opt_out.key, key->key, key->keylen);
2281 tcp_sigpool_algo(key->tcp_sigpool_id, opt_out.alg_name, 64);
2282
2283 /* Copy key to user */
2284 if (copy_to_sockptr_offset(optval, out_offset,
2285 &opt_out, bytes_to_write))
2286 return -EFAULT;
2287 out_offset += user_len;
2288 }
2289
2290 optlen_out = (int)sizeof(struct tcp_ao_getsockopt);
2291 if (copy_to_sockptr(optlen, &optlen_out, sizeof(int)))
2292 return -EFAULT;
2293
2294 out_offset = offsetof(struct tcp_ao_getsockopt, nkeys);
2295 if (copy_to_sockptr_offset(optval, out_offset,
2296 &matched_keys, sizeof(u32)))
2297 return -EFAULT;
2298
2299 return 0;
2300 }
2301
2302 int tcp_ao_get_mkts(struct sock *sk, sockptr_t optval, sockptr_t optlen)
2303 {
2304 struct tcp_ao_info *ao_info;
2305
2306 ao_info = setsockopt_ao_info(sk);
2307 if (IS_ERR(ao_info))
2308 return PTR_ERR(ao_info);
2309 if (!ao_info)
2310 return -ENOENT;
2311
2312 return tcp_ao_copy_mkts_to_user(ao_info, optval, optlen);
2313 }
2314
2315 int tcp_ao_get_sock_info(struct sock *sk, sockptr_t optval, sockptr_t optlen)
2316 {
2317 struct tcp_ao_info_opt out, in = {};
2318 struct tcp_ao_key *current_key;
2319 struct tcp_ao_info *ao;
2320 int err, len;
2321
2322 if (copy_from_sockptr(&len, optlen, sizeof(int)))
2323 return -EFAULT;
2324
2325 if (len <= 0)
2326 return -EINVAL;
2327
2328 /* Copying this "in" only to check ::reserved, ::reserved2,
2329 * that may be needed to extend (struct tcp_ao_info_opt) and
2330 * what getsockopt() provides in future.
2331 */
2332 err = copy_struct_from_sockptr(&in, sizeof(in), optval, len);
2333 if (err)
2334 return err;
2335
2336 if (in.reserved != 0 || in.reserved2 != 0)
2337 return -EINVAL;
2338
2339 ao = setsockopt_ao_info(sk);
2340 if (IS_ERR(ao))
2341 return PTR_ERR(ao);
2342 if (!ao)
2343 return -ENOENT;
2344
2345 memset(&out, 0, sizeof(out));
2346 out.ao_required = ao->ao_required;
2347 out.accept_icmps = ao->accept_icmps;
2348 out.pkt_good = atomic64_read(&ao->counters.pkt_good);
2349 out.pkt_bad = atomic64_read(&ao->counters.pkt_bad);
2350 out.pkt_key_not_found = atomic64_read(&ao->counters.key_not_found);
2351 out.pkt_ao_required = atomic64_read(&ao->counters.ao_required);
2352 out.pkt_dropped_icmp = atomic64_read(&ao->counters.dropped_icmp);
2353
2354 current_key = READ_ONCE(ao->current_key);
2355 if (current_key) {
2356 out.set_current = 1;
2357 out.current_key = current_key->sndid;
2358 }
2359 if (ao->rnext_key) {
2360 out.set_rnext = 1;
2361 out.rnext = ao->rnext_key->rcvid;
2362 }
2363
2364 if (copy_to_sockptr(optval, &out, min_t(int, len, sizeof(out))))
2365 return -EFAULT;
2366
2367 return 0;
2368 }
2369
2370 int tcp_ao_set_repair(struct sock *sk, sockptr_t optval, unsigned int optlen)
2371 {
2372 struct tcp_sock *tp = tcp_sk(sk);
2373 struct tcp_ao_repair cmd;
2374 struct tcp_ao_key *key;
2375 struct tcp_ao_info *ao;
2376 int err;
2377
2378 if (optlen < sizeof(cmd))
2379 return -EINVAL;
2380
2381 err = copy_struct_from_sockptr(&cmd, sizeof(cmd), optval, optlen);
2382 if (err)
2383 return err;
2384
2385 if (!tp->repair)
2386 return -EPERM;
2387
2388 ao = setsockopt_ao_info(sk);
2389 if (IS_ERR(ao))
2390 return PTR_ERR(ao);
2391 if (!ao)
2392 return -ENOENT;
2393
2394 WRITE_ONCE(ao->lisn, cmd.snt_isn);
2395 WRITE_ONCE(ao->risn, cmd.rcv_isn);
2396 WRITE_ONCE(ao->snd_sne, cmd.snd_sne);
2397 WRITE_ONCE(ao->rcv_sne, cmd.rcv_sne);
2398
2399 hlist_for_each_entry_rcu(key, &ao->head, node)
2400 tcp_ao_cache_traffic_keys(sk, ao, key);
2401
2402 return 0;
2403 }
2404
2405 int tcp_ao_get_repair(struct sock *sk, sockptr_t optval, sockptr_t optlen)
2406 {
2407 struct tcp_sock *tp = tcp_sk(sk);
2408 struct tcp_ao_repair opt;
2409 struct tcp_ao_info *ao;
2410 int len;
2411
2412 if (copy_from_sockptr(&len, optlen, sizeof(int)))
2413 return -EFAULT;
2414
2415 if (len <= 0)
2416 return -EINVAL;
2417
2418 if (!tp->repair)
2419 return -EPERM;
2420
2421 rcu_read_lock();
2422 ao = getsockopt_ao_info(sk);
2423 if (IS_ERR_OR_NULL(ao)) {
2424 rcu_read_unlock();
2425 return ao ? PTR_ERR(ao) : -ENOENT;
2426 }
2427
2428 opt.snt_isn = ao->lisn;
2429 opt.rcv_isn = ao->risn;
2430 opt.snd_sne = READ_ONCE(ao->snd_sne);
2431 opt.rcv_sne = READ_ONCE(ao->rcv_sne);
2432 rcu_read_unlock();
2433
2434 if (copy_to_sockptr(optval, &opt, min_t(int, len, sizeof(opt))))
2435 return -EFAULT;
2436 return 0;
2437 }
2438
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.