blob: 8b07f3a4f2db2509bed581ab549c09b621c8b7ea [file] [log] [blame]
Thomas Gleixner09c434b2019-05-19 13:08:20 +01001// SPDX-License-Identifier: GPL-2.0-only
Joe Perchesafd465032012-03-12 07:03:32 +00002#define pr_fmt(fmt) "IPsec: " fmt
3
Herbert Xu38320c72008-01-28 19:35:05 -08004#include <crypto/aead.h>
5#include <crypto/authenc.h>
Herbert Xu6b7326c2006-07-30 15:41:01 +10006#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007#include <linux/module.h>
8#include <net/ip.h>
9#include <net/xfrm.h>
10#include <net/esp.h>
Adrian Bunk72998d82007-10-26 22:53:58 -070011#include <linux/scatterlist.h>
Herbert Xua02a6422005-10-10 21:11:08 -070012#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/pfkeyv2.h>
Herbert Xu38320c72008-01-28 19:35:05 -080014#include <linux/rtnetlink.h>
15#include <linux/slab.h>
Herbert Xub7c6538c2007-10-09 13:33:35 -070016#include <linux/spinlock.h>
Thomas Graf2017a722007-12-10 16:53:05 -080017#include <linux/in6.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <net/icmp.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020019#include <net/protocol.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <net/udp.h>
Sabrina Dubrocae27cca92019-11-25 14:49:02 +010021#include <net/tcp.h>
22#include <net/espintcp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
Steffen Klassertcac26612017-01-17 10:22:57 +010024#include <linux/highmem.h>
25
Herbert Xu38320c72008-01-28 19:35:05 -080026struct esp_skb_cb {
27 struct xfrm_skb_cb xfrm;
28 void *tmp;
29};
30
Herbert Xu962fcef2016-06-18 13:03:36 +080031struct esp_output_extra {
32 __be32 seqhi;
33 u32 esphoff;
34};
35
Herbert Xu38320c72008-01-28 19:35:05 -080036#define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0]))
37
38/*
39 * Allocate an AEAD request structure with extra space for SG and IV.
40 *
41 * For alignment considerations the IV is placed at the front, followed
42 * by the request and finally the SG list.
43 *
44 * TODO: Use spare space in skb for this where possible.
45 */
Herbert Xu962fcef2016-06-18 13:03:36 +080046static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int extralen)
Herbert Xu38320c72008-01-28 19:35:05 -080047{
48 unsigned int len;
49
Herbert Xu962fcef2016-06-18 13:03:36 +080050 len = extralen;
Steffen Klassert0dc49e92011-03-08 00:07:14 +000051
52 len += crypto_aead_ivsize(aead);
53
Herbert Xu38320c72008-01-28 19:35:05 -080054 if (len) {
55 len += crypto_aead_alignmask(aead) &
56 ~(crypto_tfm_ctx_alignment() - 1);
57 len = ALIGN(len, crypto_tfm_ctx_alignment());
58 }
59
Herbert Xu7021b2e2015-05-27 16:03:46 +080060 len += sizeof(struct aead_request) + crypto_aead_reqsize(aead);
Herbert Xu38320c72008-01-28 19:35:05 -080061 len = ALIGN(len, __alignof__(struct scatterlist));
62
63 len += sizeof(struct scatterlist) * nfrags;
64
65 return kmalloc(len, GFP_ATOMIC);
66}
67
Herbert Xu962fcef2016-06-18 13:03:36 +080068static inline void *esp_tmp_extra(void *tmp)
Steffen Klassert0dc49e92011-03-08 00:07:14 +000069{
Herbert Xu962fcef2016-06-18 13:03:36 +080070 return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra));
Steffen Klassert0dc49e92011-03-08 00:07:14 +000071}
Herbert Xu962fcef2016-06-18 13:03:36 +080072
73static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int extralen)
Herbert Xu38320c72008-01-28 19:35:05 -080074{
75 return crypto_aead_ivsize(aead) ?
Herbert Xu962fcef2016-06-18 13:03:36 +080076 PTR_ALIGN((u8 *)tmp + extralen,
77 crypto_aead_alignmask(aead) + 1) : tmp + extralen;
Herbert Xu38320c72008-01-28 19:35:05 -080078}
79
Herbert Xu38320c72008-01-28 19:35:05 -080080static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv)
81{
82 struct aead_request *req;
83
84 req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
85 crypto_tfm_ctx_alignment());
86 aead_request_set_tfm(req, aead);
87 return req;
88}
89
90static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead,
91 struct aead_request *req)
92{
93 return (void *)ALIGN((unsigned long)(req + 1) +
94 crypto_aead_reqsize(aead),
95 __alignof__(struct scatterlist));
96}
97
Steffen Klassertcac26612017-01-17 10:22:57 +010098static void esp_ssg_unref(struct xfrm_state *x, void *tmp)
99{
100 struct esp_output_extra *extra = esp_tmp_extra(tmp);
101 struct crypto_aead *aead = x->data;
102 int extralen = 0;
103 u8 *iv;
104 struct aead_request *req;
105 struct scatterlist *sg;
106
107 if (x->props.flags & XFRM_STATE_ESN)
108 extralen += sizeof(*extra);
109
110 extra = esp_tmp_extra(tmp);
111 iv = esp_tmp_iv(aead, tmp, extralen);
112 req = esp_tmp_req(aead, iv);
113
114 /* Unref skb_frag_pages in the src scatterlist if necessary.
115 * Skip the first sg which comes from skb->data.
116 */
117 if (req->src != req->dst)
118 for (sg = sg_next(req->src); sg; sg = sg_next(sg))
119 put_page(sg_page(sg));
120}
121
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100122#ifdef CONFIG_INET_ESPINTCP
123struct esp_tcp_sk {
124 struct sock *sk;
125 struct rcu_head rcu;
126};
127
128static void esp_free_tcp_sk(struct rcu_head *head)
129{
130 struct esp_tcp_sk *esk = container_of(head, struct esp_tcp_sk, rcu);
131
132 sock_put(esk->sk);
133 kfree(esk);
134}
135
136static struct sock *esp_find_tcp_sk(struct xfrm_state *x)
137{
138 struct xfrm_encap_tmpl *encap = x->encap;
139 struct esp_tcp_sk *esk;
140 __be16 sport, dport;
141 struct sock *nsk;
142 struct sock *sk;
143
144 sk = rcu_dereference(x->encap_sk);
145 if (sk && sk->sk_state == TCP_ESTABLISHED)
146 return sk;
147
148 spin_lock_bh(&x->lock);
149 sport = encap->encap_sport;
150 dport = encap->encap_dport;
151 nsk = rcu_dereference_protected(x->encap_sk,
152 lockdep_is_held(&x->lock));
153 if (sk && sk == nsk) {
154 esk = kmalloc(sizeof(*esk), GFP_ATOMIC);
155 if (!esk) {
156 spin_unlock_bh(&x->lock);
157 return ERR_PTR(-ENOMEM);
158 }
159 RCU_INIT_POINTER(x->encap_sk, NULL);
160 esk->sk = sk;
161 call_rcu(&esk->rcu, esp_free_tcp_sk);
162 }
163 spin_unlock_bh(&x->lock);
164
165 sk = inet_lookup_established(xs_net(x), &tcp_hashinfo, x->id.daddr.a4,
166 dport, x->props.saddr.a4, sport, 0);
167 if (!sk)
168 return ERR_PTR(-ENOENT);
169
170 if (!tcp_is_ulp_esp(sk)) {
171 sock_put(sk);
172 return ERR_PTR(-EINVAL);
173 }
174
175 spin_lock_bh(&x->lock);
176 nsk = rcu_dereference_protected(x->encap_sk,
177 lockdep_is_held(&x->lock));
178 if (encap->encap_sport != sport ||
179 encap->encap_dport != dport) {
180 sock_put(sk);
181 sk = nsk ?: ERR_PTR(-EREMCHG);
182 } else if (sk == nsk) {
183 sock_put(sk);
184 } else {
185 rcu_assign_pointer(x->encap_sk, sk);
186 }
187 spin_unlock_bh(&x->lock);
188
189 return sk;
190}
191
192static int esp_output_tcp_finish(struct xfrm_state *x, struct sk_buff *skb)
193{
194 struct sock *sk;
195 int err;
196
197 rcu_read_lock();
198
199 sk = esp_find_tcp_sk(x);
200 err = PTR_ERR_OR_ZERO(sk);
201 if (err)
202 goto out;
203
204 bh_lock_sock(sk);
205 if (sock_owned_by_user(sk))
206 err = espintcp_queue_out(sk, skb);
207 else
208 err = espintcp_push_skb(sk, skb);
209 bh_unlock_sock(sk);
210
211out:
212 rcu_read_unlock();
213 return err;
214}
215
216static int esp_output_tcp_encap_cb(struct net *net, struct sock *sk,
217 struct sk_buff *skb)
218{
219 struct dst_entry *dst = skb_dst(skb);
220 struct xfrm_state *x = dst->xfrm;
221
222 return esp_output_tcp_finish(x, skb);
223}
224
225static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb)
226{
227 int err;
228
229 local_bh_disable();
230 err = xfrm_trans_queue_net(xs_net(x), skb, esp_output_tcp_encap_cb);
231 local_bh_enable();
232
233 /* EINPROGRESS just happens to do the right thing. It
234 * actually means that the skb has been consumed and
235 * isn't coming back.
236 */
237 return err ?: -EINPROGRESS;
238}
239#else
240static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb)
241{
242 kfree_skb(skb);
243
244 return -EOPNOTSUPP;
245}
246#endif
247
Herbert Xu38320c72008-01-28 19:35:05 -0800248static void esp_output_done(struct crypto_async_request *base, int err)
249{
250 struct sk_buff *skb = base->data;
Steffen Klassertf53c7232017-12-20 10:41:36 +0100251 struct xfrm_offload *xo = xfrm_offload(skb);
Steffen Klassertcac26612017-01-17 10:22:57 +0100252 void *tmp;
Steffen Klassertf53c7232017-12-20 10:41:36 +0100253 struct xfrm_state *x;
254
Florian Westphal2294be0f2018-12-18 17:15:20 +0100255 if (xo && (xo->flags & XFRM_DEV_RESUME)) {
256 struct sec_path *sp = skb_sec_path(skb);
257
258 x = sp->xvec[sp->len - 1];
259 } else {
Steffen Klassertf53c7232017-12-20 10:41:36 +0100260 x = skb_dst(skb)->xfrm;
Florian Westphal2294be0f2018-12-18 17:15:20 +0100261 }
Herbert Xu38320c72008-01-28 19:35:05 -0800262
Steffen Klassertcac26612017-01-17 10:22:57 +0100263 tmp = ESP_SKB_CB(skb)->tmp;
264 esp_ssg_unref(x, tmp);
265 kfree(tmp);
Steffen Klassertf53c7232017-12-20 10:41:36 +0100266
267 if (xo && (xo->flags & XFRM_DEV_RESUME)) {
268 if (err) {
269 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
270 kfree_skb(skb);
271 return;
272 }
273
274 skb_push(skb, skb->data - skb_mac_header(skb));
275 secpath_reset(skb);
276 xfrm_dev_resume(skb);
277 } else {
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100278 if (!err &&
279 x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP)
280 esp_output_tail_tcp(x, skb);
281 else
282 xfrm_output_resume(skb, err);
Steffen Klassertf53c7232017-12-20 10:41:36 +0100283 }
Herbert Xu38320c72008-01-28 19:35:05 -0800284}
285
Herbert Xu7021b2e2015-05-27 16:03:46 +0800286/* Move ESP header back into place. */
287static void esp_restore_header(struct sk_buff *skb, unsigned int offset)
288{
289 struct ip_esp_hdr *esph = (void *)(skb->data + offset);
290 void *tmp = ESP_SKB_CB(skb)->tmp;
Herbert Xu962fcef2016-06-18 13:03:36 +0800291 __be32 *seqhi = esp_tmp_extra(tmp);
Herbert Xu7021b2e2015-05-27 16:03:46 +0800292
293 esph->seq_no = esph->spi;
294 esph->spi = *seqhi;
295}
296
297static void esp_output_restore_header(struct sk_buff *skb)
298{
Herbert Xu962fcef2016-06-18 13:03:36 +0800299 void *tmp = ESP_SKB_CB(skb)->tmp;
300 struct esp_output_extra *extra = esp_tmp_extra(tmp);
301
302 esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff -
303 sizeof(__be32));
Herbert Xu7021b2e2015-05-27 16:03:46 +0800304}
305
Steffen Klassertcac26612017-01-17 10:22:57 +0100306static struct ip_esp_hdr *esp_output_set_extra(struct sk_buff *skb,
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200307 struct xfrm_state *x,
Steffen Klassertcac26612017-01-17 10:22:57 +0100308 struct ip_esp_hdr *esph,
309 struct esp_output_extra *extra)
310{
Steffen Klassertcac26612017-01-17 10:22:57 +0100311 /* For ESN we move the header forward by 4 bytes to
312 * accomodate the high bits. We will move it back after
313 * encryption.
314 */
315 if ((x->props.flags & XFRM_STATE_ESN)) {
Steffen Klassert7862b402017-04-14 10:06:50 +0200316 __u32 seqhi;
317 struct xfrm_offload *xo = xfrm_offload(skb);
318
319 if (xo)
320 seqhi = xo->seq.hi;
321 else
322 seqhi = XFRM_SKB_CB(skb)->seq.output.hi;
323
Steffen Klassertcac26612017-01-17 10:22:57 +0100324 extra->esphoff = (unsigned char *)esph -
325 skb_transport_header(skb);
326 esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4);
327 extra->seqhi = esph->spi;
Steffen Klassert7862b402017-04-14 10:06:50 +0200328 esph->seq_no = htonl(seqhi);
Steffen Klassertcac26612017-01-17 10:22:57 +0100329 }
330
331 esph->spi = x->id.spi;
332
333 return esph;
334}
335
Herbert Xu7021b2e2015-05-27 16:03:46 +0800336static void esp_output_done_esn(struct crypto_async_request *base, int err)
337{
338 struct sk_buff *skb = base->data;
339
340 esp_output_restore_header(skb);
341 esp_output_done(base, err);
342}
343
Sabrina Dubrocaeecd227a2019-11-25 14:49:01 +0100344static struct ip_esp_hdr *esp_output_udp_encap(struct sk_buff *skb,
345 int encap_type,
346 struct esp_info *esp,
347 __be16 sport,
348 __be16 dport)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349{
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200350 struct udphdr *uh;
351 __be32 *udpdata32;
Sabrina Dubroca8dfb4eb2019-03-25 14:30:00 +0100352 unsigned int len;
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200353
Sabrina Dubrocaeecd227a2019-11-25 14:49:01 +0100354 len = skb->len + esp->tailen - skb_transport_offset(skb);
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100355 if (len + sizeof(struct iphdr) > IP_MAX_MTU)
Sabrina Dubrocaeecd227a2019-11-25 14:49:01 +0100356 return ERR_PTR(-EMSGSIZE);
357
358 uh = (struct udphdr *)esp->esph;
359 uh->source = sport;
360 uh->dest = dport;
361 uh->len = htons(len);
362 uh->check = 0;
363
364 *skb_mac_header(skb) = IPPROTO_UDP;
365
366 if (encap_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
367 udpdata32 = (__be32 *)(uh + 1);
368 udpdata32[0] = udpdata32[1] = 0;
369 return (struct ip_esp_hdr *)(udpdata32 + 2);
370 }
371
372 return (struct ip_esp_hdr *)(uh + 1);
373}
374
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100375#ifdef CONFIG_INET_ESPINTCP
376static struct ip_esp_hdr *esp_output_tcp_encap(struct xfrm_state *x,
377 struct sk_buff *skb,
378 struct esp_info *esp)
379{
380 __be16 *lenp = (void *)esp->esph;
381 struct ip_esp_hdr *esph;
382 unsigned int len;
383 struct sock *sk;
384
385 len = skb->len + esp->tailen - skb_transport_offset(skb);
386 if (len > IP_MAX_MTU)
387 return ERR_PTR(-EMSGSIZE);
388
389 rcu_read_lock();
390 sk = esp_find_tcp_sk(x);
391 rcu_read_unlock();
392
393 if (IS_ERR(sk))
394 return ERR_CAST(sk);
395
396 *lenp = htons(len);
397 esph = (struct ip_esp_hdr *)(lenp + 1);
398
399 return esph;
400}
401#else
402static struct ip_esp_hdr *esp_output_tcp_encap(struct xfrm_state *x,
403 struct sk_buff *skb,
404 struct esp_info *esp)
405{
406 return ERR_PTR(-EOPNOTSUPP);
407}
408#endif
409
Sabrina Dubrocaeecd227a2019-11-25 14:49:01 +0100410static int esp_output_encap(struct xfrm_state *x, struct sk_buff *skb,
411 struct esp_info *esp)
412{
413 struct xfrm_encap_tmpl *encap = x->encap;
414 struct ip_esp_hdr *esph;
415 __be16 sport, dport;
416 int encap_type;
417
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200418 spin_lock_bh(&x->lock);
419 sport = encap->encap_sport;
420 dport = encap->encap_dport;
421 encap_type = encap->encap_type;
422 spin_unlock_bh(&x->lock);
423
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200424 switch (encap_type) {
425 default:
426 case UDP_ENCAP_ESPINUDP:
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200427 case UDP_ENCAP_ESPINUDP_NON_IKE:
Sabrina Dubrocaeecd227a2019-11-25 14:49:01 +0100428 esph = esp_output_udp_encap(skb, encap_type, esp, sport, dport);
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200429 break;
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100430 case TCP_ENCAP_ESPINTCP:
431 esph = esp_output_tcp_encap(x, skb, esp);
432 break;
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200433 }
434
Sabrina Dubrocaeecd227a2019-11-25 14:49:01 +0100435 if (IS_ERR(esph))
436 return PTR_ERR(esph);
437
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200438 esp->esph = esph;
Sabrina Dubroca8dfb4eb2019-03-25 14:30:00 +0100439
440 return 0;
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200441}
442
443int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
444{
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700445 u8 *tail;
Steffen Klassertcac26612017-01-17 10:22:57 +0100446 u8 *vaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 int nfrags;
Steffen Klassert0e78a872017-05-03 08:44:27 +0200448 int esph_offset;
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200449 struct page *page;
450 struct sk_buff *trailer;
451 int tailen = esp->tailen;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100453 /* this is non-NULL only with TCP/UDP Encapsulation */
Sabrina Dubroca8dfb4eb2019-03-25 14:30:00 +0100454 if (x->encap) {
Sabrina Dubrocaeecd227a2019-11-25 14:49:01 +0100455 int err = esp_output_encap(x, skb, esp);
Sabrina Dubroca8dfb4eb2019-03-25 14:30:00 +0100456
457 if (err < 0)
458 return err;
459 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460
Steffen Klassertcac26612017-01-17 10:22:57 +0100461 if (!skb_cloned(skb)) {
Steffen Klassert54ffd792017-08-25 07:34:35 +0200462 if (tailen <= skb_tailroom(skb)) {
Steffen Klassertcac26612017-01-17 10:22:57 +0100463 nfrags = 1;
464 trailer = skb;
465 tail = skb_tail_pointer(trailer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466
Steffen Klassertcac26612017-01-17 10:22:57 +0100467 goto skip_cow;
468 } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS)
469 && !skb_has_frag_list(skb)) {
470 int allocsize;
471 struct sock *sk = skb->sk;
472 struct page_frag *pfrag = &x->xfrag;
Herbert Xu7021b2e2015-05-27 16:03:46 +0800473
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200474 esp->inplace = false;
475
Steffen Klassertcac26612017-01-17 10:22:57 +0100476 allocsize = ALIGN(tailen, L1_CACHE_BYTES);
477
478 spin_lock_bh(&x->lock);
479
480 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
481 spin_unlock_bh(&x->lock);
482 goto cow;
483 }
484
485 page = pfrag->page;
486 get_page(page);
487
488 vaddr = kmap_atomic(page);
489
490 tail = vaddr + pfrag->offset;
491
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200492 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
Steffen Klassertcac26612017-01-17 10:22:57 +0100493
494 kunmap_atomic(vaddr);
495
496 nfrags = skb_shinfo(skb)->nr_frags;
497
498 __skb_fill_page_desc(skb, nfrags, page, pfrag->offset,
499 tailen);
500 skb_shinfo(skb)->nr_frags = ++nfrags;
501
502 pfrag->offset = pfrag->offset + allocsize;
Steffen Klassert36ff0dd2017-08-25 07:16:07 +0200503
504 spin_unlock_bh(&x->lock);
505
Steffen Klassertcac26612017-01-17 10:22:57 +0100506 nfrags++;
507
508 skb->len += tailen;
509 skb->data_len += tailen;
510 skb->truesize += tailen;
Martin Willi09db5122019-01-28 09:35:35 +0100511 if (sk && sk_fullsock(sk))
Reshetova, Elena14afee42017-06-30 13:08:00 +0300512 refcount_add(tailen, &sk->sk_wmem_alloc);
Steffen Klassertcac26612017-01-17 10:22:57 +0100513
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200514 goto out;
Steffen Klassertcac26612017-01-17 10:22:57 +0100515 }
Herbert Xu7021b2e2015-05-27 16:03:46 +0800516 }
517
Steffen Klassertcac26612017-01-17 10:22:57 +0100518cow:
Steffen Klassert0e78a872017-05-03 08:44:27 +0200519 esph_offset = (unsigned char *)esp->esph - skb_transport_header(skb);
520
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200521 nfrags = skb_cow_data(skb, tailen, &trailer);
522 if (nfrags < 0)
523 goto out;
Steffen Klassertcac26612017-01-17 10:22:57 +0100524 tail = skb_tail_pointer(trailer);
Steffen Klassert0e78a872017-05-03 08:44:27 +0200525 esp->esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset);
Steffen Klassertcac26612017-01-17 10:22:57 +0100526
527skip_cow:
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200528 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
529 pskb_put(skb, trailer, tailen);
Steffen Klassertcac26612017-01-17 10:22:57 +0100530
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200531out:
532 return nfrags;
533}
534EXPORT_SYMBOL_GPL(esp_output_head);
Herbert Xu7021b2e2015-05-27 16:03:46 +0800535
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200536int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
537{
538 u8 *iv;
539 int alen;
540 void *tmp;
541 int ivlen;
542 int assoclen;
543 int extralen;
544 struct page *page;
545 struct ip_esp_hdr *esph;
546 struct crypto_aead *aead;
547 struct aead_request *req;
548 struct scatterlist *sg, *dsg;
549 struct esp_output_extra *extra;
550 int err = -ENOMEM;
551
552 assoclen = sizeof(struct ip_esp_hdr);
553 extralen = 0;
554
555 if (x->props.flags & XFRM_STATE_ESN) {
556 extralen += sizeof(*extra);
557 assoclen += sizeof(__be32);
558 }
559
560 aead = x->data;
561 alen = crypto_aead_authsize(aead);
562 ivlen = crypto_aead_ivsize(aead);
563
564 tmp = esp_alloc_tmp(aead, esp->nfrags + 2, extralen);
Steffen Klasserte892d2d2017-04-24 07:33:56 +0200565 if (!tmp)
Steffen Klassertcac26612017-01-17 10:22:57 +0100566 goto error;
Steffen Klassertcac26612017-01-17 10:22:57 +0100567
568 extra = esp_tmp_extra(tmp);
569 iv = esp_tmp_iv(aead, tmp, extralen);
570 req = esp_tmp_req(aead, iv);
571 sg = esp_req_sg(aead, req);
Steffen Klassertcac26612017-01-17 10:22:57 +0100572
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200573 if (esp->inplace)
574 dsg = sg;
575 else
576 dsg = &sg[esp->nfrags];
Steffen Klassertcac26612017-01-17 10:22:57 +0100577
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200578 esph = esp_output_set_extra(skb, x, esp->esph, extra);
579 esp->esph = esph;
580
581 sg_init_table(sg, esp->nfrags);
Jason A. Donenfeld3f297702017-06-04 04:16:23 +0200582 err = skb_to_sgvec(skb, sg,
583 (unsigned char *)esph - skb->data,
584 assoclen + ivlen + esp->clen + alen);
585 if (unlikely(err < 0))
Steffen Klasserte6194922017-07-13 09:13:30 +0200586 goto error_free;
Steffen Klassert0dc49e92011-03-08 00:07:14 +0000587
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200588 if (!esp->inplace) {
589 int allocsize;
590 struct page_frag *pfrag = &x->xfrag;
591
592 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES);
593
594 spin_lock_bh(&x->lock);
595 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
596 spin_unlock_bh(&x->lock);
Steffen Klasserte6194922017-07-13 09:13:30 +0200597 goto error_free;
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200598 }
599
600 skb_shinfo(skb)->nr_frags = 1;
601
602 page = pfrag->page;
603 get_page(page);
604 /* replace page frags in skb with new page */
605 __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len);
606 pfrag->offset = pfrag->offset + allocsize;
607 spin_unlock_bh(&x->lock);
608
609 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1);
Jason A. Donenfeld3f297702017-06-04 04:16:23 +0200610 err = skb_to_sgvec(skb, dsg,
611 (unsigned char *)esph - skb->data,
612 assoclen + ivlen + esp->clen + alen);
613 if (unlikely(err < 0))
Steffen Klasserte6194922017-07-13 09:13:30 +0200614 goto error_free;
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200615 }
616
Steffen Klassertcac26612017-01-17 10:22:57 +0100617 if ((x->props.flags & XFRM_STATE_ESN))
618 aead_request_set_callback(req, 0, esp_output_done_esn, skb);
619 else
620 aead_request_set_callback(req, 0, esp_output_done, skb);
621
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200622 aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv);
Herbert Xu7021b2e2015-05-27 16:03:46 +0800623 aead_request_set_ad(req, assoclen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
Herbert Xu7021b2e2015-05-27 16:03:46 +0800625 memset(iv, 0, ivlen);
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200626 memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8),
Herbert Xu7021b2e2015-05-27 16:03:46 +0800627 min(ivlen, 8));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628
Herbert Xu38320c72008-01-28 19:35:05 -0800629 ESP_SKB_CB(skb)->tmp = tmp;
Herbert Xu7021b2e2015-05-27 16:03:46 +0800630 err = crypto_aead_encrypt(req);
631
632 switch (err) {
633 case -EINPROGRESS:
Herbert Xu38320c72008-01-28 19:35:05 -0800634 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635
Gilad Ben-Yossef068c2e72017-10-18 08:00:35 +0100636 case -ENOSPC:
Herbert Xu38320c72008-01-28 19:35:05 -0800637 err = NET_XMIT_DROP;
Herbert Xu7021b2e2015-05-27 16:03:46 +0800638 break;
639
640 case 0:
641 if ((x->props.flags & XFRM_STATE_ESN))
642 esp_output_restore_header(skb);
643 }
Herbert Xu6b7326c2006-07-30 15:41:01 +1000644
Steffen Klassertcac26612017-01-17 10:22:57 +0100645 if (sg != dsg)
646 esp_ssg_unref(x, tmp);
Herbert Xub7c6538c2007-10-09 13:33:35 -0700647
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100648 if (!err && x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP)
649 err = esp_output_tail_tcp(x, skb);
650
Steffen Klasserte6194922017-07-13 09:13:30 +0200651error_free:
652 kfree(tmp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653error:
654 return err;
655}
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200656EXPORT_SYMBOL_GPL(esp_output_tail);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200658static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
659{
660 int alen;
661 int blksize;
662 struct ip_esp_hdr *esph;
663 struct crypto_aead *aead;
664 struct esp_info esp;
665
666 esp.inplace = true;
667
668 esp.proto = *skb_mac_header(skb);
669 *skb_mac_header(skb) = IPPROTO_ESP;
670
671 /* skb is pure payload to encrypt */
672
673 aead = x->data;
674 alen = crypto_aead_authsize(aead);
675
676 esp.tfclen = 0;
677 if (x->tfcpad) {
678 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb);
679 u32 padto;
680
Florian Westphalc7b37c72019-06-24 22:04:48 +0200681 padto = min(x->tfcpad, xfrm_state_mtu(x, dst->child_mtu_cached));
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200682 if (skb->len < padto)
683 esp.tfclen = padto - skb->len;
684 }
685 blksize = ALIGN(crypto_aead_blocksize(aead), 4);
686 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
687 esp.plen = esp.clen - skb->len - esp.tfclen;
688 esp.tailen = esp.tfclen + esp.plen + alen;
689
690 esp.esph = ip_esp_hdr(skb);
691
692 esp.nfrags = esp_output_head(x, skb, &esp);
693 if (esp.nfrags < 0)
694 return esp.nfrags;
695
696 esph = esp.esph;
697 esph->spi = x->id.spi;
698
699 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
700 esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low +
701 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32));
702
703 skb_push(skb, -skb_network_offset(skb));
704
705 return esp_output_tail(x, skb, &esp);
706}
707
Yossi Kuperman47ebcc02017-08-30 11:30:39 +0300708static inline int esp_remove_trailer(struct sk_buff *skb)
709{
710 struct xfrm_state *x = xfrm_input_state(skb);
711 struct xfrm_offload *xo = xfrm_offload(skb);
712 struct crypto_aead *aead = x->data;
713 int alen, hlen, elen;
714 int padlen, trimlen;
715 __wsum csumdiff;
716 u8 nexthdr[2];
717 int ret;
718
719 alen = crypto_aead_authsize(aead);
720 hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
721 elen = skb->len - hlen;
722
723 if (xo && (xo->flags & XFRM_ESP_NO_TRAILER)) {
724 ret = xo->proto;
725 goto out;
726 }
727
728 if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2))
729 BUG();
730
731 ret = -EINVAL;
732 padlen = nexthdr[0];
733 if (padlen + 2 + alen >= elen) {
734 net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n",
735 padlen + 2, elen - alen);
736 goto out;
737 }
738
739 trimlen = alen + padlen + 2;
740 if (skb->ip_summed == CHECKSUM_COMPLETE) {
741 csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0);
742 skb->csum = csum_block_sub(skb->csum, csumdiff,
743 skb->len - trimlen);
744 }
745 pskb_trim(skb, skb->len - trimlen);
746
747 ret = nexthdr[1];
748
749out:
750 return ret;
751}
752
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200753int esp_input_done2(struct sk_buff *skb, int err)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754{
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000755 const struct iphdr *iph;
Herbert Xu38320c72008-01-28 19:35:05 -0800756 struct xfrm_state *x = xfrm_input_state(skb);
Steffen Klassertd77e38e2017-04-14 10:06:10 +0200757 struct xfrm_offload *xo = xfrm_offload(skb);
Mathias Krause1c5ad132013-10-18 12:09:05 +0200758 struct crypto_aead *aead = x->data;
Herbert Xu38320c72008-01-28 19:35:05 -0800759 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
Herbert Xu31a4ab92006-05-27 23:06:13 -0700760 int ihl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761
Steffen Klassertd77e38e2017-04-14 10:06:10 +0200762 if (!xo || (xo && !(xo->flags & CRYPTO_DONE)))
763 kfree(ESP_SKB_CB(skb)->tmp);
Herbert Xu0ebea8e2007-11-13 21:45:58 -0800764
Herbert Xu6b7326c2006-07-30 15:41:01 +1000765 if (unlikely(err))
Herbert Xu668dc8a2007-12-16 15:55:02 -0800766 goto out;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800767
Yossi Kuperman47ebcc02017-08-30 11:30:39 +0300768 err = esp_remove_trailer(skb);
769 if (unlikely(err < 0))
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800770 goto out;
771
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700772 iph = ip_hdr(skb);
Herbert Xu31a4ab92006-05-27 23:06:13 -0700773 ihl = iph->ihl * 4;
774
Herbert Xu752c1f42006-02-27 13:00:40 -0800775 if (x->encap) {
776 struct xfrm_encap_tmpl *encap = x->encap;
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100777 struct tcphdr *th = (void *)(skb_network_header(skb) + ihl);
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700778 struct udphdr *uh = (void *)(skb_network_header(skb) + ihl);
Sabrina Dubroca25f68022019-11-25 14:49:00 +0100779 __be16 source;
780
781 switch (x->encap->encap_type) {
Sabrina Dubrocae27cca92019-11-25 14:49:02 +0100782 case TCP_ENCAP_ESPINTCP:
783 source = th->source;
784 break;
Sabrina Dubroca25f68022019-11-25 14:49:00 +0100785 case UDP_ENCAP_ESPINUDP:
786 case UDP_ENCAP_ESPINUDP_NON_IKE:
787 source = uh->source;
788 break;
789 default:
790 WARN_ON_ONCE(1);
791 err = -EINVAL;
792 goto out;
793 }
Herbert Xu752c1f42006-02-27 13:00:40 -0800794
795 /*
796 * 1) if the NAT-T peer's IP or port changed then
797 * advertize the change to the keying daemon.
798 * This is an inbound SA, so just compare
799 * SRC ports.
800 */
801 if (iph->saddr != x->props.saddr.a4 ||
Sabrina Dubroca25f68022019-11-25 14:49:00 +0100802 source != encap->encap_sport) {
Herbert Xu752c1f42006-02-27 13:00:40 -0800803 xfrm_address_t ipaddr;
804
805 ipaddr.a4 = iph->saddr;
Sabrina Dubroca25f68022019-11-25 14:49:00 +0100806 km_new_mapping(x, &ipaddr, source);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900807
Herbert Xu752c1f42006-02-27 13:00:40 -0800808 /* XXX: perhaps add an extra
809 * policy check here, to see
810 * if we should allow or
811 * reject a packet from a
812 * different source
813 * address/port.
814 */
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800815 }
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900816
Herbert Xu752c1f42006-02-27 13:00:40 -0800817 /*
818 * 2) ignore UDP/TCP checksums in case
819 * of NAT-T in Transport Mode, or
820 * perform other post-processing fixes
821 * as per draft-ietf-ipsec-udp-encaps-06,
822 * section 3.1.2
823 */
Herbert Xu8bd17072007-10-10 15:41:41 -0700824 if (x->props.mode == XFRM_MODE_TRANSPORT)
Herbert Xu752c1f42006-02-27 13:00:40 -0800825 skb->ip_summed = CHECKSUM_UNNECESSARY;
Herbert Xu4bf05ec2006-02-27 13:00:01 -0800826 }
827
Ilan Tayariec9567a2017-08-01 12:49:04 +0300828 skb_pull_rcsum(skb, hlen);
Li RongQing7143dfa2012-12-28 16:07:16 +0800829 if (x->props.mode == XFRM_MODE_TUNNEL)
830 skb_reset_transport_header(skb);
831 else
832 skb_set_transport_header(skb, -ihl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833
Herbert Xu38320c72008-01-28 19:35:05 -0800834 /* RFC4303: Drop dummy packets without any error */
835 if (err == IPPROTO_NONE)
836 err = -EINVAL;
837
838out:
839 return err;
840}
Steffen Klassertfca11eb2017-04-14 10:06:33 +0200841EXPORT_SYMBOL_GPL(esp_input_done2);
Herbert Xu38320c72008-01-28 19:35:05 -0800842
843static void esp_input_done(struct crypto_async_request *base, int err)
844{
845 struct sk_buff *skb = base->data;
846
847 xfrm_input_resume(skb, esp_input_done2(skb, err));
848}
849
Herbert Xu7021b2e2015-05-27 16:03:46 +0800850static void esp_input_restore_header(struct sk_buff *skb)
851{
852 esp_restore_header(skb, 0);
853 __skb_pull(skb, 4);
854}
855
Steffen Klassertcac26612017-01-17 10:22:57 +0100856static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi)
857{
858 struct xfrm_state *x = xfrm_input_state(skb);
Colin Ian King60aa8042018-01-30 14:53:48 +0000859 struct ip_esp_hdr *esph;
Steffen Klassertcac26612017-01-17 10:22:57 +0100860
861 /* For ESN we move the header forward by 4 bytes to
862 * accomodate the high bits. We will move it back after
863 * decryption.
864 */
865 if ((x->props.flags & XFRM_STATE_ESN)) {
Johannes Bergd58ff352017-06-16 14:29:23 +0200866 esph = skb_push(skb, 4);
Steffen Klassertcac26612017-01-17 10:22:57 +0100867 *seqhi = esph->spi;
868 esph->spi = esph->seq_no;
869 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi;
870 }
871}
872
Herbert Xu7021b2e2015-05-27 16:03:46 +0800873static void esp_input_done_esn(struct crypto_async_request *base, int err)
874{
875 struct sk_buff *skb = base->data;
876
877 esp_input_restore_header(skb);
878 esp_input_done(base, err);
879}
880
Herbert Xu38320c72008-01-28 19:35:05 -0800881/*
882 * Note: detecting truncated vs. non-truncated authentication data is very
883 * expensive, so we only support truncated data, which is the recommended
884 * and common case.
885 */
886static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
887{
Mathias Krause1c5ad132013-10-18 12:09:05 +0200888 struct crypto_aead *aead = x->data;
Herbert Xu38320c72008-01-28 19:35:05 -0800889 struct aead_request *req;
890 struct sk_buff *trailer;
Herbert Xu7021b2e2015-05-27 16:03:46 +0800891 int ivlen = crypto_aead_ivsize(aead);
Haishuang Yan0c05f982018-08-17 15:51:00 +0800892 int elen = skb->len - sizeof(struct ip_esp_hdr) - ivlen;
Herbert Xu38320c72008-01-28 19:35:05 -0800893 int nfrags;
Steffen Klassert0dc49e92011-03-08 00:07:14 +0000894 int assoclen;
Steffen Klassert0dc49e92011-03-08 00:07:14 +0000895 int seqhilen;
896 __be32 *seqhi;
Herbert Xu38320c72008-01-28 19:35:05 -0800897 void *tmp;
898 u8 *iv;
899 struct scatterlist *sg;
Herbert Xu38320c72008-01-28 19:35:05 -0800900 int err = -EINVAL;
901
Haishuang Yan0c05f982018-08-17 15:51:00 +0800902 if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + ivlen))
Herbert Xu38320c72008-01-28 19:35:05 -0800903 goto out;
904
905 if (elen <= 0)
906 goto out;
907
Haishuang Yan0c05f982018-08-17 15:51:00 +0800908 assoclen = sizeof(struct ip_esp_hdr);
Steffen Klassert0dc49e92011-03-08 00:07:14 +0000909 seqhilen = 0;
910
911 if (x->props.flags & XFRM_STATE_ESN) {
Steffen Klassert0dc49e92011-03-08 00:07:14 +0000912 seqhilen += sizeof(__be32);
913 assoclen += seqhilen;
914 }
915
Steffen Klassertcac26612017-01-17 10:22:57 +0100916 if (!skb_cloned(skb)) {
917 if (!skb_is_nonlinear(skb)) {
918 nfrags = 1;
919
920 goto skip_cow;
921 } else if (!skb_has_frag_list(skb)) {
922 nfrags = skb_shinfo(skb)->nr_frags;
923 nfrags++;
924
925 goto skip_cow;
926 }
927 }
928
929 err = skb_cow_data(skb, 0, &trailer);
930 if (err < 0)
931 goto out;
932
933 nfrags = err;
934
935skip_cow:
Herbert Xu38320c72008-01-28 19:35:05 -0800936 err = -ENOMEM;
Herbert Xu7021b2e2015-05-27 16:03:46 +0800937 tmp = esp_alloc_tmp(aead, nfrags, seqhilen);
Herbert Xu38320c72008-01-28 19:35:05 -0800938 if (!tmp)
939 goto out;
940
941 ESP_SKB_CB(skb)->tmp = tmp;
Herbert Xu962fcef2016-06-18 13:03:36 +0800942 seqhi = esp_tmp_extra(tmp);
Steffen Klassert0dc49e92011-03-08 00:07:14 +0000943 iv = esp_tmp_iv(aead, tmp, seqhilen);
Herbert Xu38320c72008-01-28 19:35:05 -0800944 req = esp_tmp_req(aead, iv);
Herbert Xu7021b2e2015-05-27 16:03:46 +0800945 sg = esp_req_sg(aead, req);
Herbert Xu38320c72008-01-28 19:35:05 -0800946
Steffen Klassertcac26612017-01-17 10:22:57 +0100947 esp_input_set_header(skb, seqhi);
Herbert Xu38320c72008-01-28 19:35:05 -0800948
949 sg_init_table(sg, nfrags);
Jason A. Donenfeld3f297702017-06-04 04:16:23 +0200950 err = skb_to_sgvec(skb, sg, 0, skb->len);
Steffen Klasserte6194922017-07-13 09:13:30 +0200951 if (unlikely(err < 0)) {
952 kfree(tmp);
Jason A. Donenfeld3f297702017-06-04 04:16:23 +0200953 goto out;
Steffen Klasserte6194922017-07-13 09:13:30 +0200954 }
Steffen Klassert0dc49e92011-03-08 00:07:14 +0000955
Steffen Klassertcac26612017-01-17 10:22:57 +0100956 skb->ip_summed = CHECKSUM_NONE;
957
958 if ((x->props.flags & XFRM_STATE_ESN))
959 aead_request_set_callback(req, 0, esp_input_done_esn, skb);
960 else
961 aead_request_set_callback(req, 0, esp_input_done, skb);
962
Herbert Xu7021b2e2015-05-27 16:03:46 +0800963 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv);
964 aead_request_set_ad(req, assoclen);
Herbert Xu38320c72008-01-28 19:35:05 -0800965
966 err = crypto_aead_decrypt(req);
967 if (err == -EINPROGRESS)
968 goto out;
969
Herbert Xu7021b2e2015-05-27 16:03:46 +0800970 if ((x->props.flags & XFRM_STATE_ESN))
971 esp_input_restore_header(skb);
972
Herbert Xu38320c72008-01-28 19:35:05 -0800973 err = esp_input_done2(skb, err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974
975out:
Herbert Xu668dc8a2007-12-16 15:55:02 -0800976 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977}
978
Steffen Klassert827789c2014-02-21 08:41:08 +0100979static int esp4_err(struct sk_buff *skb, u32 info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980{
Alexey Dobriyan4fb236b2008-11-25 17:59:27 -0800981 struct net *net = dev_net(skb->dev);
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000982 const struct iphdr *iph = (const struct iphdr *)skb->data;
Jianjun Kongd93191002008-11-03 00:23:42 -0800983 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984 struct xfrm_state *x;
985
David S. Miller55be7a92012-07-11 21:27:49 -0700986 switch (icmp_hdr(skb)->type) {
987 case ICMP_DEST_UNREACH:
988 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
Steffen Klassert827789c2014-02-21 08:41:08 +0100989 return 0;
David S. Miller55be7a92012-07-11 21:27:49 -0700990 case ICMP_REDIRECT:
991 break;
992 default:
Steffen Klassert827789c2014-02-21 08:41:08 +0100993 return 0;
David S. Miller55be7a92012-07-11 21:27:49 -0700994 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000996 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
997 esph->spi, IPPROTO_ESP, AF_INET);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998 if (!x)
Steffen Klassert827789c2014-02-21 08:41:08 +0100999 return 0;
David S. Miller55be7a92012-07-11 21:27:49 -07001000
Timo Teräs387aa652013-05-27 20:46:31 +00001001 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
Maciej Żenczykowskid888f392018-09-25 20:56:26 -07001002 ipv4_update_pmtu(skb, net, info, 0, IPPROTO_ESP);
Timo Teräs387aa652013-05-27 20:46:31 +00001003 else
Maciej Żenczykowski1042caa2018-09-25 20:56:27 -07001004 ipv4_redirect(skb, net, 0, IPPROTO_ESP);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005 xfrm_state_put(x);
Steffen Klassert827789c2014-02-21 08:41:08 +01001006
1007 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008}
1009
1010static void esp_destroy(struct xfrm_state *x)
1011{
Mathias Krause1c5ad132013-10-18 12:09:05 +02001012 struct crypto_aead *aead = x->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013
Mathias Krause1c5ad132013-10-18 12:09:05 +02001014 if (!aead)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 return;
1016
Mathias Krause1c5ad132013-10-18 12:09:05 +02001017 crypto_free_aead(aead);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018}
1019
Herbert Xu1a6509d2008-01-28 19:37:29 -08001020static int esp_init_aead(struct xfrm_state *x)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001021{
Herbert Xu7021b2e2015-05-27 16:03:46 +08001022 char aead_name[CRYPTO_MAX_ALG_NAME];
Herbert Xu1a6509d2008-01-28 19:37:29 -08001023 struct crypto_aead *aead;
1024 int err;
1025
Herbert Xu7021b2e2015-05-27 16:03:46 +08001026 err = -ENAMETOOLONG;
1027 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
1028 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
1029 goto error;
1030
Steffen Klassertf58869c2017-12-20 10:41:53 +01001031 aead = crypto_alloc_aead(aead_name, 0, 0);
Herbert Xu1a6509d2008-01-28 19:37:29 -08001032 err = PTR_ERR(aead);
1033 if (IS_ERR(aead))
1034 goto error;
1035
Mathias Krause1c5ad132013-10-18 12:09:05 +02001036 x->data = aead;
Herbert Xu1a6509d2008-01-28 19:37:29 -08001037
1038 err = crypto_aead_setkey(aead, x->aead->alg_key,
1039 (x->aead->alg_key_len + 7) / 8);
1040 if (err)
1041 goto error;
1042
1043 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8);
1044 if (err)
1045 goto error;
1046
1047error:
1048 return err;
1049}
1050
1051static int esp_init_authenc(struct xfrm_state *x)
1052{
Herbert Xu38320c72008-01-28 19:35:05 -08001053 struct crypto_aead *aead;
1054 struct crypto_authenc_key_param *param;
1055 struct rtattr *rta;
1056 char *key;
1057 char *p;
1058 char authenc_name[CRYPTO_MAX_ALG_NAME];
Herbert Xu38320c72008-01-28 19:35:05 -08001059 unsigned int keylen;
1060 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001061
Herbert Xu1a6509d2008-01-28 19:37:29 -08001062 err = -EINVAL;
Ian Morris51456b22015-04-03 09:17:26 +01001063 if (!x->ealg)
Herbert Xu1a6509d2008-01-28 19:37:29 -08001064 goto error;
Herbert Xu38320c72008-01-28 19:35:05 -08001065
Herbert Xu1a6509d2008-01-28 19:37:29 -08001066 err = -ENAMETOOLONG;
Steffen Klassert0dc49e92011-03-08 00:07:14 +00001067
1068 if ((x->props.flags & XFRM_STATE_ESN)) {
1069 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
Herbert Xu7021b2e2015-05-27 16:03:46 +08001070 "%s%sauthencesn(%s,%s)%s",
1071 x->geniv ?: "", x->geniv ? "(" : "",
Steffen Klassert0dc49e92011-03-08 00:07:14 +00001072 x->aalg ? x->aalg->alg_name : "digest_null",
Herbert Xu7021b2e2015-05-27 16:03:46 +08001073 x->ealg->alg_name,
1074 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
Steffen Klassert0dc49e92011-03-08 00:07:14 +00001075 goto error;
1076 } else {
1077 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
Herbert Xu7021b2e2015-05-27 16:03:46 +08001078 "%s%sauthenc(%s,%s)%s",
1079 x->geniv ?: "", x->geniv ? "(" : "",
Steffen Klassert0dc49e92011-03-08 00:07:14 +00001080 x->aalg ? x->aalg->alg_name : "digest_null",
Herbert Xu7021b2e2015-05-27 16:03:46 +08001081 x->ealg->alg_name,
1082 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
Steffen Klassert0dc49e92011-03-08 00:07:14 +00001083 goto error;
1084 }
Herbert Xu38320c72008-01-28 19:35:05 -08001085
Steffen Klassertf58869c2017-12-20 10:41:53 +01001086 aead = crypto_alloc_aead(authenc_name, 0, 0);
Herbert Xu38320c72008-01-28 19:35:05 -08001087 err = PTR_ERR(aead);
1088 if (IS_ERR(aead))
1089 goto error;
1090
Mathias Krause1c5ad132013-10-18 12:09:05 +02001091 x->data = aead;
Herbert Xu38320c72008-01-28 19:35:05 -08001092
1093 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) +
1094 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param));
1095 err = -ENOMEM;
1096 key = kmalloc(keylen, GFP_KERNEL);
1097 if (!key)
1098 goto error;
1099
1100 p = key;
1101 rta = (void *)p;
1102 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
1103 rta->rta_len = RTA_LENGTH(sizeof(*param));
1104 param = RTA_DATA(rta);
1105 p += RTA_SPACE(sizeof(*param));
1106
Linus Torvalds1da177e2005-04-16 15:20:36 -07001107 if (x->aalg) {
1108 struct xfrm_algo_desc *aalg_desc;
1109
Herbert Xu38320c72008-01-28 19:35:05 -08001110 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8);
1111 p += (x->aalg->alg_key_len + 7) / 8;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001112
1113 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
1114 BUG_ON(!aalg_desc);
1115
Herbert Xu38320c72008-01-28 19:35:05 -08001116 err = -EINVAL;
Joe Perches45083492014-11-05 15:36:08 -08001117 if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
Herbert Xu38320c72008-01-28 19:35:05 -08001118 crypto_aead_authsize(aead)) {
Joe Perches45083492014-11-05 15:36:08 -08001119 pr_info("ESP: %s digestsize %u != %hu\n",
1120 x->aalg->alg_name,
1121 crypto_aead_authsize(aead),
1122 aalg_desc->uinfo.auth.icv_fullbits / 8);
Herbert Xu38320c72008-01-28 19:35:05 -08001123 goto free_key;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001124 }
1125
Herbert Xu38320c72008-01-28 19:35:05 -08001126 err = crypto_aead_setauthsize(
Martin Willi8f8a0882009-11-25 00:29:53 +00001127 aead, x->aalg->alg_trunc_len / 8);
Herbert Xu38320c72008-01-28 19:35:05 -08001128 if (err)
1129 goto free_key;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001130 }
Herbert Xu4b7137f2007-10-08 17:13:44 -07001131
Herbert Xu38320c72008-01-28 19:35:05 -08001132 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
1133 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
1134
1135 err = crypto_aead_setkey(aead, key, keylen);
1136
1137free_key:
1138 kfree(key);
1139
Herbert Xu1a6509d2008-01-28 19:37:29 -08001140error:
1141 return err;
1142}
1143
1144static int esp_init_state(struct xfrm_state *x)
1145{
Herbert Xu1a6509d2008-01-28 19:37:29 -08001146 struct crypto_aead *aead;
1147 u32 align;
1148 int err;
1149
Mathias Krause1c5ad132013-10-18 12:09:05 +02001150 x->data = NULL;
Herbert Xu1a6509d2008-01-28 19:37:29 -08001151
1152 if (x->aead)
1153 err = esp_init_aead(x);
1154 else
1155 err = esp_init_authenc(x);
1156
Herbert Xu38320c72008-01-28 19:35:05 -08001157 if (err)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158 goto error;
Herbert Xu38320c72008-01-28 19:35:05 -08001159
Mathias Krause1c5ad132013-10-18 12:09:05 +02001160 aead = x->data;
Herbert Xu1a6509d2008-01-28 19:37:29 -08001161
Herbert Xu38320c72008-01-28 19:35:05 -08001162 x->props.header_len = sizeof(struct ip_esp_hdr) +
1163 crypto_aead_ivsize(aead);
Masahide NAKAMURA7e49e6d2006-09-22 15:05:15 -07001164 if (x->props.mode == XFRM_MODE_TUNNEL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001165 x->props.header_len += sizeof(struct iphdr);
Joakim Koskelaeb49e632008-08-06 02:39:30 -07001166 else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6)
Patrick McHardyac758e32007-04-09 11:47:58 -07001167 x->props.header_len += IPV4_BEET_PHMAXLEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001168 if (x->encap) {
1169 struct xfrm_encap_tmpl *encap = x->encap;
1170
1171 switch (encap->encap_type) {
1172 default:
Herbert Xubcfd09f2018-01-05 22:12:32 +11001173 err = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174 goto error;
1175 case UDP_ENCAP_ESPINUDP:
1176 x->props.header_len += sizeof(struct udphdr);
1177 break;
1178 case UDP_ENCAP_ESPINUDP_NON_IKE:
1179 x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32);
1180 break;
Sabrina Dubrocae27cca92019-11-25 14:49:02 +01001181#ifdef CONFIG_INET_ESPINTCP
1182 case TCP_ENCAP_ESPINTCP:
1183 /* only the length field, TCP encap is done by
1184 * the socket
1185 */
1186 x->props.header_len += 2;
1187 break;
1188#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001189 }
1190 }
Herbert Xu38320c72008-01-28 19:35:05 -08001191
1192 align = ALIGN(crypto_aead_blocksize(aead), 4);
Mathias Krause1c5ad132013-10-18 12:09:05 +02001193 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001194
1195error:
Herbert Xu38320c72008-01-28 19:35:05 -08001196 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001197}
1198
Steffen Klassert827789c2014-02-21 08:41:08 +01001199static int esp4_rcv_cb(struct sk_buff *skb, int err)
1200{
1201 return 0;
1202}
1203
Eric Dumazet533cb5b2008-01-30 19:11:50 -08001204static const struct xfrm_type esp_type =
Linus Torvalds1da177e2005-04-16 15:20:36 -07001205{
1206 .description = "ESP4",
1207 .owner = THIS_MODULE,
1208 .proto = IPPROTO_ESP,
Herbert Xu436a0a42007-10-08 17:25:53 -07001209 .flags = XFRM_TYPE_REPLAY_PROT,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001210 .init_state = esp_init_state,
1211 .destructor = esp_destroy,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001212 .input = esp_input,
Steffen Klassertfca11eb2017-04-14 10:06:33 +02001213 .output = esp_output,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001214};
1215
Steffen Klassert827789c2014-02-21 08:41:08 +01001216static struct xfrm4_protocol esp4_protocol = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001217 .handler = xfrm4_rcv,
Steffen Klassert827789c2014-02-21 08:41:08 +01001218 .input_handler = xfrm_input,
1219 .cb_handler = esp4_rcv_cb,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001220 .err_handler = esp4_err,
Steffen Klassert827789c2014-02-21 08:41:08 +01001221 .priority = 0,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001222};
1223
1224static int __init esp4_init(void)
1225{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001226 if (xfrm_register_type(&esp_type, AF_INET) < 0) {
Joe Perches058bd4d2012-03-11 18:36:11 +00001227 pr_info("%s: can't add xfrm type\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228 return -EAGAIN;
1229 }
Steffen Klassert827789c2014-02-21 08:41:08 +01001230 if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) {
Joe Perches058bd4d2012-03-11 18:36:11 +00001231 pr_info("%s: can't add protocol\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001232 xfrm_unregister_type(&esp_type, AF_INET);
1233 return -EAGAIN;
1234 }
1235 return 0;
1236}
1237
1238static void __exit esp4_fini(void)
1239{
Steffen Klassert827789c2014-02-21 08:41:08 +01001240 if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0)
Joe Perches058bd4d2012-03-11 18:36:11 +00001241 pr_info("%s: can't remove protocol\n", __func__);
Florian Westphal4f518e82019-05-03 17:46:19 +02001242 xfrm_unregister_type(&esp_type, AF_INET);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243}
1244
1245module_init(esp4_init);
1246module_exit(esp4_fini);
1247MODULE_LICENSE("GPL");
Masahide NAKAMURAd3d6dd32007-06-26 23:57:49 -07001248MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);