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TOMOYO Linux Cross Reference
Linux/net/ipv4/esp4.c

Version: ~ [ linux-5.4.2 ] ~ [ linux-5.3.15 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.88 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.158 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.206 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.206 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.78 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 #define pr_fmt(fmt) "IPsec: " fmt
  2 
  3 #include <crypto/aead.h>
  4 #include <crypto/authenc.h>
  5 #include <linux/err.h>
  6 #include <linux/module.h>
  7 #include <net/ip.h>
  8 #include <net/xfrm.h>
  9 #include <net/esp.h>
 10 #include <linux/scatterlist.h>
 11 #include <linux/kernel.h>
 12 #include <linux/pfkeyv2.h>
 13 #include <linux/rtnetlink.h>
 14 #include <linux/slab.h>
 15 #include <linux/spinlock.h>
 16 #include <linux/in6.h>
 17 #include <net/icmp.h>
 18 #include <net/protocol.h>
 19 #include <net/udp.h>
 20 
 21 struct esp_skb_cb {
 22         struct xfrm_skb_cb xfrm;
 23         void *tmp;
 24 };
 25 
 26 #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0]))
 27 
 28 static u32 esp4_get_mtu(struct xfrm_state *x, int mtu);
 29 
 30 /*
 31  * Allocate an AEAD request structure with extra space for SG and IV.
 32  *
 33  * For alignment considerations the IV is placed at the front, followed
 34  * by the request and finally the SG list.
 35  *
 36  * TODO: Use spare space in skb for this where possible.
 37  */
 38 static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqhilen)
 39 {
 40         unsigned int len;
 41 
 42         len = seqhilen;
 43 
 44         len += crypto_aead_ivsize(aead);
 45 
 46         if (len) {
 47                 len += crypto_aead_alignmask(aead) &
 48                        ~(crypto_tfm_ctx_alignment() - 1);
 49                 len = ALIGN(len, crypto_tfm_ctx_alignment());
 50         }
 51 
 52         len += sizeof(struct aead_givcrypt_request) + crypto_aead_reqsize(aead);
 53         len = ALIGN(len, __alignof__(struct scatterlist));
 54 
 55         len += sizeof(struct scatterlist) * nfrags;
 56 
 57         return kmalloc(len, GFP_ATOMIC);
 58 }
 59 
 60 static inline __be32 *esp_tmp_seqhi(void *tmp)
 61 {
 62         return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32));
 63 }
 64 static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen)
 65 {
 66         return crypto_aead_ivsize(aead) ?
 67                PTR_ALIGN((u8 *)tmp + seqhilen,
 68                          crypto_aead_alignmask(aead) + 1) : tmp + seqhilen;
 69 }
 70 
 71 static inline struct aead_givcrypt_request *esp_tmp_givreq(
 72         struct crypto_aead *aead, u8 *iv)
 73 {
 74         struct aead_givcrypt_request *req;
 75 
 76         req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
 77                                 crypto_tfm_ctx_alignment());
 78         aead_givcrypt_set_tfm(req, aead);
 79         return req;
 80 }
 81 
 82 static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv)
 83 {
 84         struct aead_request *req;
 85 
 86         req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
 87                                 crypto_tfm_ctx_alignment());
 88         aead_request_set_tfm(req, aead);
 89         return req;
 90 }
 91 
 92 static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead,
 93                                              struct aead_request *req)
 94 {
 95         return (void *)ALIGN((unsigned long)(req + 1) +
 96                              crypto_aead_reqsize(aead),
 97                              __alignof__(struct scatterlist));
 98 }
 99 
100 static inline struct scatterlist *esp_givreq_sg(
101         struct crypto_aead *aead, struct aead_givcrypt_request *req)
102 {
103         return (void *)ALIGN((unsigned long)(req + 1) +
104                              crypto_aead_reqsize(aead),
105                              __alignof__(struct scatterlist));
106 }
107 
108 static void esp_output_done(struct crypto_async_request *base, int err)
109 {
110         struct sk_buff *skb = base->data;
111 
112         kfree(ESP_SKB_CB(skb)->tmp);
113         xfrm_output_resume(skb, err);
114 }
115 
116 static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
117 {
118         int err;
119         struct ip_esp_hdr *esph;
120         struct crypto_aead *aead;
121         struct aead_givcrypt_request *req;
122         struct scatterlist *sg;
123         struct scatterlist *asg;
124         struct esp_data *esp;
125         struct sk_buff *trailer;
126         void *tmp;
127         u8 *iv;
128         u8 *tail;
129         int blksize;
130         int clen;
131         int alen;
132         int plen;
133         int tfclen;
134         int nfrags;
135         int assoclen;
136         int sglists;
137         int seqhilen;
138         __be32 *seqhi;
139 
140         /* skb is pure payload to encrypt */
141 
142         err = -ENOMEM;
143 
144         esp = x->data;
145         aead = esp->aead;
146         alen = crypto_aead_authsize(aead);
147 
148         tfclen = 0;
149         if (x->tfcpad) {
150                 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb);
151                 u32 padto;
152 
153                 padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached));
154                 if (skb->len < padto)
155                         tfclen = padto - skb->len;
156         }
157         blksize = ALIGN(crypto_aead_blocksize(aead), 4);
158         clen = ALIGN(skb->len + 2 + tfclen, blksize);
159         if (esp->padlen)
160                 clen = ALIGN(clen, esp->padlen);
161         plen = clen - skb->len - tfclen;
162 
163         err = skb_cow_data(skb, tfclen + plen + alen, &trailer);
164         if (err < 0)
165                 goto error;
166         nfrags = err;
167 
168         assoclen = sizeof(*esph);
169         sglists = 1;
170         seqhilen = 0;
171 
172         if (x->props.flags & XFRM_STATE_ESN) {
173                 sglists += 2;
174                 seqhilen += sizeof(__be32);
175                 assoclen += seqhilen;
176         }
177 
178         tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen);
179         if (!tmp)
180                 goto error;
181 
182         seqhi = esp_tmp_seqhi(tmp);
183         iv = esp_tmp_iv(aead, tmp, seqhilen);
184         req = esp_tmp_givreq(aead, iv);
185         asg = esp_givreq_sg(aead, req);
186         sg = asg + sglists;
187 
188         /* Fill padding... */
189         tail = skb_tail_pointer(trailer);
190         if (tfclen) {
191                 memset(tail, 0, tfclen);
192                 tail += tfclen;
193         }
194         do {
195                 int i;
196                 for (i = 0; i < plen - 2; i++)
197                         tail[i] = i + 1;
198         } while (0);
199         tail[plen - 2] = plen - 2;
200         tail[plen - 1] = *skb_mac_header(skb);
201         pskb_put(skb, trailer, clen - skb->len + alen);
202 
203         skb_push(skb, -skb_network_offset(skb));
204         esph = ip_esp_hdr(skb);
205         *skb_mac_header(skb) = IPPROTO_ESP;
206 
207         /* this is non-NULL only with UDP Encapsulation */
208         if (x->encap) {
209                 struct xfrm_encap_tmpl *encap = x->encap;
210                 struct udphdr *uh;
211                 __be32 *udpdata32;
212                 __be16 sport, dport;
213                 int encap_type;
214 
215                 spin_lock_bh(&x->lock);
216                 sport = encap->encap_sport;
217                 dport = encap->encap_dport;
218                 encap_type = encap->encap_type;
219                 spin_unlock_bh(&x->lock);
220 
221                 uh = (struct udphdr *)esph;
222                 uh->source = sport;
223                 uh->dest = dport;
224                 uh->len = htons(skb->len - skb_transport_offset(skb));
225                 uh->check = 0;
226 
227                 switch (encap_type) {
228                 default:
229                 case UDP_ENCAP_ESPINUDP:
230                         esph = (struct ip_esp_hdr *)(uh + 1);
231                         break;
232                 case UDP_ENCAP_ESPINUDP_NON_IKE:
233                         udpdata32 = (__be32 *)(uh + 1);
234                         udpdata32[0] = udpdata32[1] = 0;
235                         esph = (struct ip_esp_hdr *)(udpdata32 + 2);
236                         break;
237                 }
238 
239                 *skb_mac_header(skb) = IPPROTO_UDP;
240         }
241 
242         esph->spi = x->id.spi;
243         esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
244 
245         sg_init_table(sg, nfrags);
246         skb_to_sgvec(skb, sg,
247                      esph->enc_data + crypto_aead_ivsize(aead) - skb->data,
248                      clen + alen);
249 
250         if ((x->props.flags & XFRM_STATE_ESN)) {
251                 sg_init_table(asg, 3);
252                 sg_set_buf(asg, &esph->spi, sizeof(__be32));
253                 *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
254                 sg_set_buf(asg + 1, seqhi, seqhilen);
255                 sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32));
256         } else
257                 sg_init_one(asg, esph, sizeof(*esph));
258 
259         aead_givcrypt_set_callback(req, 0, esp_output_done, skb);
260         aead_givcrypt_set_crypt(req, sg, sg, clen, iv);
261         aead_givcrypt_set_assoc(req, asg, assoclen);
262         aead_givcrypt_set_giv(req, esph->enc_data,
263                               XFRM_SKB_CB(skb)->seq.output.low);
264 
265         ESP_SKB_CB(skb)->tmp = tmp;
266         err = crypto_aead_givencrypt(req);
267         if (err == -EINPROGRESS)
268                 goto error;
269 
270         if (err == -EBUSY)
271                 err = NET_XMIT_DROP;
272 
273         kfree(tmp);
274 
275 error:
276         return err;
277 }
278 
279 static int esp_input_done2(struct sk_buff *skb, int err)
280 {
281         const struct iphdr *iph;
282         struct xfrm_state *x = xfrm_input_state(skb);
283         struct esp_data *esp = x->data;
284         struct crypto_aead *aead = esp->aead;
285         int alen = crypto_aead_authsize(aead);
286         int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
287         int elen = skb->len - hlen;
288         int ihl;
289         u8 nexthdr[2];
290         int padlen;
291 
292         kfree(ESP_SKB_CB(skb)->tmp);
293 
294         if (unlikely(err))
295                 goto out;
296 
297         if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2))
298                 BUG();
299 
300         err = -EINVAL;
301         padlen = nexthdr[0];
302         if (padlen + 2 + alen >= elen)
303                 goto out;
304 
305         /* ... check padding bits here. Silly. :-) */
306 
307         iph = ip_hdr(skb);
308         ihl = iph->ihl * 4;
309 
310         if (x->encap) {
311                 struct xfrm_encap_tmpl *encap = x->encap;
312                 struct udphdr *uh = (void *)(skb_network_header(skb) + ihl);
313 
314                 /*
315                  * 1) if the NAT-T peer's IP or port changed then
316                  *    advertize the change to the keying daemon.
317                  *    This is an inbound SA, so just compare
318                  *    SRC ports.
319                  */
320                 if (iph->saddr != x->props.saddr.a4 ||
321                     uh->source != encap->encap_sport) {
322                         xfrm_address_t ipaddr;
323 
324                         ipaddr.a4 = iph->saddr;
325                         km_new_mapping(x, &ipaddr, uh->source);
326 
327                         /* XXX: perhaps add an extra
328                          * policy check here, to see
329                          * if we should allow or
330                          * reject a packet from a
331                          * different source
332                          * address/port.
333                          */
334                 }
335 
336                 /*
337                  * 2) ignore UDP/TCP checksums in case
338                  *    of NAT-T in Transport Mode, or
339                  *    perform other post-processing fixes
340                  *    as per draft-ietf-ipsec-udp-encaps-06,
341                  *    section 3.1.2
342                  */
343                 if (x->props.mode == XFRM_MODE_TRANSPORT)
344                         skb->ip_summed = CHECKSUM_UNNECESSARY;
345         }
346 
347         pskb_trim(skb, skb->len - alen - padlen - 2);
348         __skb_pull(skb, hlen);
349         skb_set_transport_header(skb, -ihl);
350 
351         err = nexthdr[1];
352 
353         /* RFC4303: Drop dummy packets without any error */
354         if (err == IPPROTO_NONE)
355                 err = -EINVAL;
356 
357 out:
358         return err;
359 }
360 
361 static void esp_input_done(struct crypto_async_request *base, int err)
362 {
363         struct sk_buff *skb = base->data;
364 
365         xfrm_input_resume(skb, esp_input_done2(skb, err));
366 }
367 
368 /*
369  * Note: detecting truncated vs. non-truncated authentication data is very
370  * expensive, so we only support truncated data, which is the recommended
371  * and common case.
372  */
373 static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
374 {
375         struct ip_esp_hdr *esph;
376         struct esp_data *esp = x->data;
377         struct crypto_aead *aead = esp->aead;
378         struct aead_request *req;
379         struct sk_buff *trailer;
380         int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead);
381         int nfrags;
382         int assoclen;
383         int sglists;
384         int seqhilen;
385         __be32 *seqhi;
386         void *tmp;
387         u8 *iv;
388         struct scatterlist *sg;
389         struct scatterlist *asg;
390         int err = -EINVAL;
391 
392         if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
393                 goto out;
394 
395         if (elen <= 0)
396                 goto out;
397 
398         if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
399                 goto out;
400         nfrags = err;
401 
402         assoclen = sizeof(*esph);
403         sglists = 1;
404         seqhilen = 0;
405 
406         if (x->props.flags & XFRM_STATE_ESN) {
407                 sglists += 2;
408                 seqhilen += sizeof(__be32);
409                 assoclen += seqhilen;
410         }
411 
412         err = -ENOMEM;
413         tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen);
414         if (!tmp)
415                 goto out;
416 
417         ESP_SKB_CB(skb)->tmp = tmp;
418         seqhi = esp_tmp_seqhi(tmp);
419         iv = esp_tmp_iv(aead, tmp, seqhilen);
420         req = esp_tmp_req(aead, iv);
421         asg = esp_req_sg(aead, req);
422         sg = asg + sglists;
423 
424         skb->ip_summed = CHECKSUM_NONE;
425 
426         esph = (struct ip_esp_hdr *)skb->data;
427 
428         /* Get ivec. This can be wrong, check against another impls. */
429         iv = esph->enc_data;
430 
431         sg_init_table(sg, nfrags);
432         skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen);
433 
434         if ((x->props.flags & XFRM_STATE_ESN)) {
435                 sg_init_table(asg, 3);
436                 sg_set_buf(asg, &esph->spi, sizeof(__be32));
437                 *seqhi = XFRM_SKB_CB(skb)->seq.input.hi;
438                 sg_set_buf(asg + 1, seqhi, seqhilen);
439                 sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32));
440         } else
441                 sg_init_one(asg, esph, sizeof(*esph));
442 
443         aead_request_set_callback(req, 0, esp_input_done, skb);
444         aead_request_set_crypt(req, sg, sg, elen, iv);
445         aead_request_set_assoc(req, asg, assoclen);
446 
447         err = crypto_aead_decrypt(req);
448         if (err == -EINPROGRESS)
449                 goto out;
450 
451         err = esp_input_done2(skb, err);
452 
453 out:
454         return err;
455 }
456 
457 static u32 esp4_get_mtu(struct xfrm_state *x, int mtu)
458 {
459         struct esp_data *esp = x->data;
460         u32 blksize = ALIGN(crypto_aead_blocksize(esp->aead), 4);
461         u32 align = max_t(u32, blksize, esp->padlen);
462         unsigned int net_adj;
463 
464         switch (x->props.mode) {
465         case XFRM_MODE_TRANSPORT:
466         case XFRM_MODE_BEET:
467                 net_adj = sizeof(struct iphdr);
468                 break;
469         case XFRM_MODE_TUNNEL:
470                 net_adj = 0;
471                 break;
472         default:
473                 BUG();
474         }
475 
476         return ((mtu - x->props.header_len - crypto_aead_authsize(esp->aead) -
477                  net_adj) & ~(align - 1)) + (net_adj - 2);
478 }
479 
480 static void esp4_err(struct sk_buff *skb, u32 info)
481 {
482         struct net *net = dev_net(skb->dev);
483         const struct iphdr *iph = (const struct iphdr *)skb->data;
484         struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
485         struct xfrm_state *x;
486 
487         switch (icmp_hdr(skb)->type) {
488         case ICMP_DEST_UNREACH:
489                 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
490                         return;
491         case ICMP_REDIRECT:
492                 break;
493         default:
494                 return;
495         }
496 
497         x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
498                               esph->spi, IPPROTO_ESP, AF_INET);
499         if (!x)
500                 return;
501 
502         if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
503                 ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0);
504         else
505                 ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0);
506         xfrm_state_put(x);
507 }
508 
509 static void esp_destroy(struct xfrm_state *x)
510 {
511         struct esp_data *esp = x->data;
512 
513         if (!esp)
514                 return;
515 
516         crypto_free_aead(esp->aead);
517         kfree(esp);
518 }
519 
520 static int esp_init_aead(struct xfrm_state *x)
521 {
522         struct esp_data *esp = x->data;
523         struct crypto_aead *aead;
524         int err;
525 
526         aead = crypto_alloc_aead(x->aead->alg_name, 0, 0);
527         err = PTR_ERR(aead);
528         if (IS_ERR(aead))
529                 goto error;
530 
531         esp->aead = aead;
532 
533         err = crypto_aead_setkey(aead, x->aead->alg_key,
534                                  (x->aead->alg_key_len + 7) / 8);
535         if (err)
536                 goto error;
537 
538         err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8);
539         if (err)
540                 goto error;
541 
542 error:
543         return err;
544 }
545 
546 static int esp_init_authenc(struct xfrm_state *x)
547 {
548         struct esp_data *esp = x->data;
549         struct crypto_aead *aead;
550         struct crypto_authenc_key_param *param;
551         struct rtattr *rta;
552         char *key;
553         char *p;
554         char authenc_name[CRYPTO_MAX_ALG_NAME];
555         unsigned int keylen;
556         int err;
557 
558         err = -EINVAL;
559         if (x->ealg == NULL)
560                 goto error;
561 
562         err = -ENAMETOOLONG;
563 
564         if ((x->props.flags & XFRM_STATE_ESN)) {
565                 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
566                              "authencesn(%s,%s)",
567                              x->aalg ? x->aalg->alg_name : "digest_null",
568                              x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME)
569                         goto error;
570         } else {
571                 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
572                              "authenc(%s,%s)",
573                              x->aalg ? x->aalg->alg_name : "digest_null",
574                              x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME)
575                         goto error;
576         }
577 
578         aead = crypto_alloc_aead(authenc_name, 0, 0);
579         err = PTR_ERR(aead);
580         if (IS_ERR(aead))
581                 goto error;
582 
583         esp->aead = aead;
584 
585         keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) +
586                  (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param));
587         err = -ENOMEM;
588         key = kmalloc(keylen, GFP_KERNEL);
589         if (!key)
590                 goto error;
591 
592         p = key;
593         rta = (void *)p;
594         rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
595         rta->rta_len = RTA_LENGTH(sizeof(*param));
596         param = RTA_DATA(rta);
597         p += RTA_SPACE(sizeof(*param));
598 
599         if (x->aalg) {
600                 struct xfrm_algo_desc *aalg_desc;
601 
602                 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8);
603                 p += (x->aalg->alg_key_len + 7) / 8;
604 
605                 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
606                 BUG_ON(!aalg_desc);
607 
608                 err = -EINVAL;
609                 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
610                     crypto_aead_authsize(aead)) {
611                         NETDEBUG(KERN_INFO "ESP: %s digestsize %u != %hu\n",
612                                  x->aalg->alg_name,
613                                  crypto_aead_authsize(aead),
614                                  aalg_desc->uinfo.auth.icv_fullbits/8);
615                         goto free_key;
616                 }
617 
618                 err = crypto_aead_setauthsize(
619                         aead, x->aalg->alg_trunc_len / 8);
620                 if (err)
621                         goto free_key;
622         }
623 
624         param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
625         memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
626 
627         err = crypto_aead_setkey(aead, key, keylen);
628 
629 free_key:
630         kfree(key);
631 
632 error:
633         return err;
634 }
635 
636 static int esp_init_state(struct xfrm_state *x)
637 {
638         struct esp_data *esp;
639         struct crypto_aead *aead;
640         u32 align;
641         int err;
642 
643         esp = kzalloc(sizeof(*esp), GFP_KERNEL);
644         if (esp == NULL)
645                 return -ENOMEM;
646 
647         x->data = esp;
648 
649         if (x->aead)
650                 err = esp_init_aead(x);
651         else
652                 err = esp_init_authenc(x);
653 
654         if (err)
655                 goto error;
656 
657         aead = esp->aead;
658 
659         esp->padlen = 0;
660 
661         x->props.header_len = sizeof(struct ip_esp_hdr) +
662                               crypto_aead_ivsize(aead);
663         if (x->props.mode == XFRM_MODE_TUNNEL)
664                 x->props.header_len += sizeof(struct iphdr);
665         else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6)
666                 x->props.header_len += IPV4_BEET_PHMAXLEN;
667         if (x->encap) {
668                 struct xfrm_encap_tmpl *encap = x->encap;
669 
670                 switch (encap->encap_type) {
671                 default:
672                         goto error;
673                 case UDP_ENCAP_ESPINUDP:
674                         x->props.header_len += sizeof(struct udphdr);
675                         break;
676                 case UDP_ENCAP_ESPINUDP_NON_IKE:
677                         x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32);
678                         break;
679                 }
680         }
681 
682         align = ALIGN(crypto_aead_blocksize(aead), 4);
683         if (esp->padlen)
684                 align = max_t(u32, align, esp->padlen);
685         x->props.trailer_len = align + 1 + crypto_aead_authsize(esp->aead);
686 
687 error:
688         return err;
689 }
690 
691 static const struct xfrm_type esp_type =
692 {
693         .description    = "ESP4",
694         .owner          = THIS_MODULE,
695         .proto          = IPPROTO_ESP,
696         .flags          = XFRM_TYPE_REPLAY_PROT,
697         .init_state     = esp_init_state,
698         .destructor     = esp_destroy,
699         .get_mtu        = esp4_get_mtu,
700         .input          = esp_input,
701         .output         = esp_output
702 };
703 
704 static const struct net_protocol esp4_protocol = {
705         .handler        =       xfrm4_rcv,
706         .err_handler    =       esp4_err,
707         .no_policy      =       1,
708         .netns_ok       =       1,
709 };
710 
711 static int __init esp4_init(void)
712 {
713         if (xfrm_register_type(&esp_type, AF_INET) < 0) {
714                 pr_info("%s: can't add xfrm type\n", __func__);
715                 return -EAGAIN;
716         }
717         if (inet_add_protocol(&esp4_protocol, IPPROTO_ESP) < 0) {
718                 pr_info("%s: can't add protocol\n", __func__);
719                 xfrm_unregister_type(&esp_type, AF_INET);
720                 return -EAGAIN;
721         }
722         return 0;
723 }
724 
725 static void __exit esp4_fini(void)
726 {
727         if (inet_del_protocol(&esp4_protocol, IPPROTO_ESP) < 0)
728                 pr_info("%s: can't remove protocol\n", __func__);
729         if (xfrm_unregister_type(&esp_type, AF_INET) < 0)
730                 pr_info("%s: can't remove xfrm type\n", __func__);
731 }
732 
733 module_init(esp4_init);
734 module_exit(esp4_fini);
735 MODULE_LICENSE("GPL");
736 MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);
737 

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