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arm64: dts: r8a7796: Add reset control properties for audio
[linux-2.6/btrfs-unstable.git] / net / ipv4 / esp4.c
blob65cc02bd82bc87991a29135a58c059c7916a5a35
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 #include <linux/highmem.h>
22
23 struct esp_skb_cb {
24 struct xfrm_skb_cb xfrm;
25 void *tmp;
26 };
27
28 struct esp_output_extra {
29 __be32 seqhi;
30 u32 esphoff;
31 };
32
33 #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0]))
34
35 static u32 esp4_get_mtu(struct xfrm_state *x, int mtu);
36
37 /*
38 * Allocate an AEAD request structure with extra space for SG and IV.
39 *
40 * For alignment considerations the IV is placed at the front, followed
41 * by the request and finally the SG list.
42 *
43 * TODO: Use spare space in skb for this where possible.
44 */
45 static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int extralen)
46 {
47 unsigned int len;
48
49 len = extralen;
50
51 len += crypto_aead_ivsize(aead);
52
53 if (len) {
54 len += crypto_aead_alignmask(aead) &
55 ~(crypto_tfm_ctx_alignment() - 1);
56 len = ALIGN(len, crypto_tfm_ctx_alignment());
57 }
58
59 len += sizeof(struct aead_request) + crypto_aead_reqsize(aead);
60 len = ALIGN(len, __alignof__(struct scatterlist));
61
62 len += sizeof(struct scatterlist) * nfrags;
63
64 return kmalloc(len, GFP_ATOMIC);
65 }
66
67 static inline void *esp_tmp_extra(void *tmp)
68 {
69 return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra));
70 }
71
72 static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int extralen)
73 {
74 return crypto_aead_ivsize(aead) ?
75 PTR_ALIGN((u8 *)tmp + extralen,
76 crypto_aead_alignmask(aead) + 1) : tmp + extralen;
77 }
78
79 static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv)
80 {
81 struct aead_request *req;
82
83 req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
84 crypto_tfm_ctx_alignment());
85 aead_request_set_tfm(req, aead);
86 return req;
87 }
88
89 static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead,
90 struct aead_request *req)
91 {
92 return (void *)ALIGN((unsigned long)(req + 1) +
93 crypto_aead_reqsize(aead),
94 __alignof__(struct scatterlist));
95 }
96
97 static void esp_ssg_unref(struct xfrm_state *x, void *tmp)
98 {
99 struct esp_output_extra *extra = esp_tmp_extra(tmp);
100 struct crypto_aead *aead = x->data;
101 int extralen = 0;
102 u8 *iv;
103 struct aead_request *req;
104 struct scatterlist *sg;
105
106 if (x->props.flags & XFRM_STATE_ESN)
107 extralen += sizeof(*extra);
108
109 extra = esp_tmp_extra(tmp);
110 iv = esp_tmp_iv(aead, tmp, extralen);
111 req = esp_tmp_req(aead, iv);
112
113 /* Unref skb_frag_pages in the src scatterlist if necessary.
114 * Skip the first sg which comes from skb->data.
115 */
116 if (req->src != req->dst)
117 for (sg = sg_next(req->src); sg; sg = sg_next(sg))
118 put_page(sg_page(sg));
119 }
120
121 static void esp_output_done(struct crypto_async_request *base, int err)
122 {
123 struct sk_buff *skb = base->data;
124 void *tmp;
125 struct dst_entry *dst = skb_dst(skb);
126 struct xfrm_state *x = dst->xfrm;
127
128 tmp = ESP_SKB_CB(skb)->tmp;
129 esp_ssg_unref(x, tmp);
130 kfree(tmp);
131 xfrm_output_resume(skb, err);
132 }
133
134 /* Move ESP header back into place. */
135 static void esp_restore_header(struct sk_buff *skb, unsigned int offset)
136 {
137 struct ip_esp_hdr *esph = (void *)(skb->data + offset);
138 void *tmp = ESP_SKB_CB(skb)->tmp;
139 __be32 *seqhi = esp_tmp_extra(tmp);
140
141 esph->seq_no = esph->spi;
142 esph->spi = *seqhi;
143 }
144
145 static void esp_output_restore_header(struct sk_buff *skb)
146 {
147 void *tmp = ESP_SKB_CB(skb)->tmp;
148 struct esp_output_extra *extra = esp_tmp_extra(tmp);
149
150 esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff -
151 sizeof(__be32));
152 }
153
154 static struct ip_esp_hdr *esp_output_set_extra(struct sk_buff *skb,
155 struct xfrm_state *x,
156 struct ip_esp_hdr *esph,
157 struct esp_output_extra *extra)
158 {
159 /* For ESN we move the header forward by 4 bytes to
160 * accomodate the high bits. We will move it back after
161 * encryption.
162 */
163 if ((x->props.flags & XFRM_STATE_ESN)) {
164 __u32 seqhi;
165 struct xfrm_offload *xo = xfrm_offload(skb);
166
167 if (xo)
168 seqhi = xo->seq.hi;
169 else
170 seqhi = XFRM_SKB_CB(skb)->seq.output.hi;
171
172 extra->esphoff = (unsigned char *)esph -
173 skb_transport_header(skb);
174 esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4);
175 extra->seqhi = esph->spi;
176 esph->seq_no = htonl(seqhi);
177 }
178
179 esph->spi = x->id.spi;
180
181 return esph;
182 }
183
184 static void esp_output_done_esn(struct crypto_async_request *base, int err)
185 {
186 struct sk_buff *skb = base->data;
187
188 esp_output_restore_header(skb);
189 esp_output_done(base, err);
190 }
191
192 static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto)
193 {
194 /* Fill padding... */
195 if (tfclen) {
196 memset(tail, 0, tfclen);
197 tail += tfclen;
198 }
199 do {
200 int i;
201 for (i = 0; i < plen - 2; i++)
202 tail[i] = i + 1;
203 } while (0);
204 tail[plen - 2] = plen - 2;
205 tail[plen - 1] = proto;
206 }
207
208 static void esp_output_udp_encap(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
209 {
210 int encap_type;
211 struct udphdr *uh;
212 __be32 *udpdata32;
213 __be16 sport, dport;
214 struct xfrm_encap_tmpl *encap = x->encap;
215 struct ip_esp_hdr *esph = esp->esph;
216
217 spin_lock_bh(&x->lock);
218 sport = encap->encap_sport;
219 dport = encap->encap_dport;
220 encap_type = encap->encap_type;
221 spin_unlock_bh(&x->lock);
222
223 uh = (struct udphdr *)esph;
224 uh->source = sport;
225 uh->dest = dport;
226 uh->len = htons(skb->len + esp->tailen
227 - skb_transport_offset(skb));
228 uh->check = 0;
229
230 switch (encap_type) {
231 default:
232 case UDP_ENCAP_ESPINUDP:
233 esph = (struct ip_esp_hdr *)(uh + 1);
234 break;
235 case UDP_ENCAP_ESPINUDP_NON_IKE:
236 udpdata32 = (__be32 *)(uh + 1);
237 udpdata32[0] = udpdata32[1] = 0;
238 esph = (struct ip_esp_hdr *)(udpdata32 + 2);
239 break;
240 }
241
242 *skb_mac_header(skb) = IPPROTO_UDP;
243 esp->esph = esph;
244 }
245
246 int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
247 {
248 u8 *tail;
249 u8 *vaddr;
250 int nfrags;
251 struct page *page;
252 struct sk_buff *trailer;
253 int tailen = esp->tailen;
254
255 /* this is non-NULL only with UDP Encapsulation */
256 if (x->encap)
257 esp_output_udp_encap(x, skb, esp);
258
259 if (!skb_cloned(skb)) {
260 if (tailen <= skb_availroom(skb)) {
261 nfrags = 1;
262 trailer = skb;
263 tail = skb_tail_pointer(trailer);
264
265 goto skip_cow;
266 } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS)
267 && !skb_has_frag_list(skb)) {
268 int allocsize;
269 struct sock *sk = skb->sk;
270 struct page_frag *pfrag = &x->xfrag;
271
272 esp->inplace = false;
273
274 allocsize = ALIGN(tailen, L1_CACHE_BYTES);
275
276 spin_lock_bh(&x->lock);
277
278 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
279 spin_unlock_bh(&x->lock);
280 goto cow;
281 }
282
283 page = pfrag->page;
284 get_page(page);
285
286 vaddr = kmap_atomic(page);
287
288 tail = vaddr + pfrag->offset;
289
290 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
291
292 kunmap_atomic(vaddr);
293
294 spin_unlock_bh(&x->lock);
295
296 nfrags = skb_shinfo(skb)->nr_frags;
297
298 __skb_fill_page_desc(skb, nfrags, page, pfrag->offset,
299 tailen);
300 skb_shinfo(skb)->nr_frags = ++nfrags;
301
302 pfrag->offset = pfrag->offset + allocsize;
303 nfrags++;
304
305 skb->len += tailen;
306 skb->data_len += tailen;
307 skb->truesize += tailen;
308 if (sk)
309 atomic_add(tailen, &sk->sk_wmem_alloc);
310
311 goto out;
312 }
313 }
314
315 cow:
316 nfrags = skb_cow_data(skb, tailen, &trailer);
317 if (nfrags < 0)
318 goto out;
319 tail = skb_tail_pointer(trailer);
320 esp->esph = ip_esp_hdr(skb);
321
322 skip_cow:
323 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
324 pskb_put(skb, trailer, tailen);
325
326 out:
327 return nfrags;
328 }
329 EXPORT_SYMBOL_GPL(esp_output_head);
330
331 int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
332 {
333 u8 *iv;
334 int alen;
335 void *tmp;
336 int ivlen;
337 int assoclen;
338 int extralen;
339 struct page *page;
340 struct ip_esp_hdr *esph;
341 struct crypto_aead *aead;
342 struct aead_request *req;
343 struct scatterlist *sg, *dsg;
344 struct esp_output_extra *extra;
345 int err = -ENOMEM;
346
347 assoclen = sizeof(struct ip_esp_hdr);
348 extralen = 0;
349
350 if (x->props.flags & XFRM_STATE_ESN) {
351 extralen += sizeof(*extra);
352 assoclen += sizeof(__be32);
353 }
354
355 aead = x->data;
356 alen = crypto_aead_authsize(aead);
357 ivlen = crypto_aead_ivsize(aead);
358
359 tmp = esp_alloc_tmp(aead, esp->nfrags + 2, extralen);
360 if (!tmp)
361 goto error;
362
363 extra = esp_tmp_extra(tmp);
364 iv = esp_tmp_iv(aead, tmp, extralen);
365 req = esp_tmp_req(aead, iv);
366 sg = esp_req_sg(aead, req);
367
368 if (esp->inplace)
369 dsg = sg;
370 else
371 dsg = &sg[esp->nfrags];
372
373 esph = esp_output_set_extra(skb, x, esp->esph, extra);
374 esp->esph = esph;
375
376 sg_init_table(sg, esp->nfrags);
377 skb_to_sgvec(skb, sg,
378 (unsigned char *)esph - skb->data,
379 assoclen + ivlen + esp->clen + alen);
380
381 if (!esp->inplace) {
382 int allocsize;
383 struct page_frag *pfrag = &x->xfrag;
384
385 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES);
386
387 spin_lock_bh(&x->lock);
388 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
389 spin_unlock_bh(&x->lock);
390 goto error;
391 }
392
393 skb_shinfo(skb)->nr_frags = 1;
394
395 page = pfrag->page;
396 get_page(page);
397 /* replace page frags in skb with new page */
398 __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len);
399 pfrag->offset = pfrag->offset + allocsize;
400 spin_unlock_bh(&x->lock);
401
402 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1);
403 skb_to_sgvec(skb, dsg,
404 (unsigned char *)esph - skb->data,
405 assoclen + ivlen + esp->clen + alen);
406 }
407
408 if ((x->props.flags & XFRM_STATE_ESN))
409 aead_request_set_callback(req, 0, esp_output_done_esn, skb);
410 else
411 aead_request_set_callback(req, 0, esp_output_done, skb);
412
413 aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv);
414 aead_request_set_ad(req, assoclen);
415
416 memset(iv, 0, ivlen);
417 memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8),
418 min(ivlen, 8));
419
420 ESP_SKB_CB(skb)->tmp = tmp;
421 err = crypto_aead_encrypt(req);
422
423 switch (err) {
424 case -EINPROGRESS:
425 goto error;
426
427 case -EBUSY:
428 err = NET_XMIT_DROP;
429 break;
430
431 case 0:
432 if ((x->props.flags & XFRM_STATE_ESN))
433 esp_output_restore_header(skb);
434 }
435
436 if (sg != dsg)
437 esp_ssg_unref(x, tmp);
438 kfree(tmp);
439
440 error:
441 return err;
442 }
443 EXPORT_SYMBOL_GPL(esp_output_tail);
444
445 static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
446 {
447 int alen;
448 int blksize;
449 struct ip_esp_hdr *esph;
450 struct crypto_aead *aead;
451 struct esp_info esp;
452
453 esp.inplace = true;
454
455 esp.proto = *skb_mac_header(skb);
456 *skb_mac_header(skb) = IPPROTO_ESP;
457
458 /* skb is pure payload to encrypt */
459
460 aead = x->data;
461 alen = crypto_aead_authsize(aead);
462
463 esp.tfclen = 0;
464 if (x->tfcpad) {
465 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb);
466 u32 padto;
467
468 padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached));
469 if (skb->len < padto)
470 esp.tfclen = padto - skb->len;
471 }
472 blksize = ALIGN(crypto_aead_blocksize(aead), 4);
473 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
474 esp.plen = esp.clen - skb->len - esp.tfclen;
475 esp.tailen = esp.tfclen + esp.plen + alen;
476
477 esp.esph = ip_esp_hdr(skb);
478
479 esp.nfrags = esp_output_head(x, skb, &esp);
480 if (esp.nfrags < 0)
481 return esp.nfrags;
482
483 esph = esp.esph;
484 esph->spi = x->id.spi;
485
486 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
487 esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low +
488 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32));
489
490 skb_push(skb, -skb_network_offset(skb));
491
492 return esp_output_tail(x, skb, &esp);
493 }
494
495 int esp_input_done2(struct sk_buff *skb, int err)
496 {
497 const struct iphdr *iph;
498 struct xfrm_state *x = xfrm_input_state(skb);
499 struct xfrm_offload *xo = xfrm_offload(skb);
500 struct crypto_aead *aead = x->data;
501 int alen = crypto_aead_authsize(aead);
502 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
503 int elen = skb->len - hlen;
504 int ihl;
505 u8 nexthdr[2];
506 int padlen;
507
508 if (!xo || (xo && !(xo->flags & CRYPTO_DONE)))
509 kfree(ESP_SKB_CB(skb)->tmp);
510
511 if (unlikely(err))
512 goto out;
513
514 if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2))
515 BUG();
516
517 err = -EINVAL;
518 padlen = nexthdr[0];
519 if (padlen + 2 + alen >= elen)
520 goto out;
521
522 /* ... check padding bits here. Silly. :-) */
523
524 iph = ip_hdr(skb);
525 ihl = iph->ihl * 4;
526
527 if (x->encap) {
528 struct xfrm_encap_tmpl *encap = x->encap;
529 struct udphdr *uh = (void *)(skb_network_header(skb) + ihl);
530
531 /*
532 * 1) if the NAT-T peer's IP or port changed then
533 * advertize the change to the keying daemon.
534 * This is an inbound SA, so just compare
535 * SRC ports.
536 */
537 if (iph->saddr != x->props.saddr.a4 ||
538 uh->source != encap->encap_sport) {
539 xfrm_address_t ipaddr;
540
541 ipaddr.a4 = iph->saddr;
542 km_new_mapping(x, &ipaddr, uh->source);
543
544 /* XXX: perhaps add an extra
545 * policy check here, to see
546 * if we should allow or
547 * reject a packet from a
548 * different source
549 * address/port.
550 */
551 }
552
553 /*
554 * 2) ignore UDP/TCP checksums in case
555 * of NAT-T in Transport Mode, or
556 * perform other post-processing fixes
557 * as per draft-ietf-ipsec-udp-encaps-06,
558 * section 3.1.2
559 */
560 if (x->props.mode == XFRM_MODE_TRANSPORT)
561 skb->ip_summed = CHECKSUM_UNNECESSARY;
562 }
563
564 pskb_trim(skb, skb->len - alen - padlen - 2);
565 __skb_pull(skb, hlen);
566 if (x->props.mode == XFRM_MODE_TUNNEL)
567 skb_reset_transport_header(skb);
568 else
569 skb_set_transport_header(skb, -ihl);
570
571 err = nexthdr[1];
572
573 /* RFC4303: Drop dummy packets without any error */
574 if (err == IPPROTO_NONE)
575 err = -EINVAL;
576
577 out:
578 return err;
579 }
580 EXPORT_SYMBOL_GPL(esp_input_done2);
581
582 static void esp_input_done(struct crypto_async_request *base, int err)
583 {
584 struct sk_buff *skb = base->data;
585
586 xfrm_input_resume(skb, esp_input_done2(skb, err));
587 }
588
589 static void esp_input_restore_header(struct sk_buff *skb)
590 {
591 esp_restore_header(skb, 0);
592 __skb_pull(skb, 4);
593 }
594
595 static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi)
596 {
597 struct xfrm_state *x = xfrm_input_state(skb);
598 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)skb->data;
599
600 /* For ESN we move the header forward by 4 bytes to
601 * accomodate the high bits. We will move it back after
602 * decryption.
603 */
604 if ((x->props.flags & XFRM_STATE_ESN)) {
605 esph = (void *)skb_push(skb, 4);
606 *seqhi = esph->spi;
607 esph->spi = esph->seq_no;
608 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi;
609 }
610 }
611
612 static void esp_input_done_esn(struct crypto_async_request *base, int err)
613 {
614 struct sk_buff *skb = base->data;
615
616 esp_input_restore_header(skb);
617 esp_input_done(base, err);
618 }
619
620 /*
621 * Note: detecting truncated vs. non-truncated authentication data is very
622 * expensive, so we only support truncated data, which is the recommended
623 * and common case.
624 */
625 static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
626 {
627 struct ip_esp_hdr *esph;
628 struct crypto_aead *aead = x->data;
629 struct aead_request *req;
630 struct sk_buff *trailer;
631 int ivlen = crypto_aead_ivsize(aead);
632 int elen = skb->len - sizeof(*esph) - ivlen;
633 int nfrags;
634 int assoclen;
635 int seqhilen;
636 __be32 *seqhi;
637 void *tmp;
638 u8 *iv;
639 struct scatterlist *sg;
640 int err = -EINVAL;
641
642 if (!pskb_may_pull(skb, sizeof(*esph) + ivlen))
643 goto out;
644
645 if (elen <= 0)
646 goto out;
647
648 assoclen = sizeof(*esph);
649 seqhilen = 0;
650
651 if (x->props.flags & XFRM_STATE_ESN) {
652 seqhilen += sizeof(__be32);
653 assoclen += seqhilen;
654 }
655
656 if (!skb_cloned(skb)) {
657 if (!skb_is_nonlinear(skb)) {
658 nfrags = 1;
659
660 goto skip_cow;
661 } else if (!skb_has_frag_list(skb)) {
662 nfrags = skb_shinfo(skb)->nr_frags;
663 nfrags++;
664
665 goto skip_cow;
666 }
667 }
668
669 err = skb_cow_data(skb, 0, &trailer);
670 if (err < 0)
671 goto out;
672
673 nfrags = err;
674
675 skip_cow:
676 err = -ENOMEM;
677 tmp = esp_alloc_tmp(aead, nfrags, seqhilen);
678 if (!tmp)
679 goto out;
680
681 ESP_SKB_CB(skb)->tmp = tmp;
682 seqhi = esp_tmp_extra(tmp);
683 iv = esp_tmp_iv(aead, tmp, seqhilen);
684 req = esp_tmp_req(aead, iv);
685 sg = esp_req_sg(aead, req);
686
687 esp_input_set_header(skb, seqhi);
688
689 sg_init_table(sg, nfrags);
690 skb_to_sgvec(skb, sg, 0, skb->len);
691
692 skb->ip_summed = CHECKSUM_NONE;
693
694 if ((x->props.flags & XFRM_STATE_ESN))
695 aead_request_set_callback(req, 0, esp_input_done_esn, skb);
696 else
697 aead_request_set_callback(req, 0, esp_input_done, skb);
698
699 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv);
700 aead_request_set_ad(req, assoclen);
701
702 err = crypto_aead_decrypt(req);
703 if (err == -EINPROGRESS)
704 goto out;
705
706 if ((x->props.flags & XFRM_STATE_ESN))
707 esp_input_restore_header(skb);
708
709 err = esp_input_done2(skb, err);
710
711 out:
712 return err;
713 }
714
715 static u32 esp4_get_mtu(struct xfrm_state *x, int mtu)
716 {
717 struct crypto_aead *aead = x->data;
718 u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4);
719 unsigned int net_adj;
720
721 switch (x->props.mode) {
722 case XFRM_MODE_TRANSPORT:
723 case XFRM_MODE_BEET:
724 net_adj = sizeof(struct iphdr);
725 break;
726 case XFRM_MODE_TUNNEL:
727 net_adj = 0;
728 break;
729 default:
730 BUG();
731 }
732
733 return ((mtu - x->props.header_len - crypto_aead_authsize(aead) -
734 net_adj) & ~(blksize - 1)) + net_adj - 2;
735 }
736
737 static int esp4_err(struct sk_buff *skb, u32 info)
738 {
739 struct net *net = dev_net(skb->dev);
740 const struct iphdr *iph = (const struct iphdr *)skb->data;
741 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
742 struct xfrm_state *x;
743
744 switch (icmp_hdr(skb)->type) {
745 case ICMP_DEST_UNREACH:
746 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
747 return 0;
748 case ICMP_REDIRECT:
749 break;
750 default:
751 return 0;
752 }
753
754 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
755 esph->spi, IPPROTO_ESP, AF_INET);
756 if (!x)
757 return 0;
758
759 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
760 ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0);
761 else
762 ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0);
763 xfrm_state_put(x);
764
765 return 0;
766 }
767
768 static void esp_destroy(struct xfrm_state *x)
769 {
770 struct crypto_aead *aead = x->data;
771
772 if (!aead)
773 return;
774
775 crypto_free_aead(aead);
776 }
777
778 static int esp_init_aead(struct xfrm_state *x)
779 {
780 char aead_name[CRYPTO_MAX_ALG_NAME];
781 struct crypto_aead *aead;
782 int err;
783 u32 mask = 0;
784
785 err = -ENAMETOOLONG;
786 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
787 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
788 goto error;
789
790 if (x->xso.offload_handle)
791 mask |= CRYPTO_ALG_ASYNC;
792
793 aead = crypto_alloc_aead(aead_name, 0, mask);
794 err = PTR_ERR(aead);
795 if (IS_ERR(aead))
796 goto error;
797
798 x->data = aead;
799
800 err = crypto_aead_setkey(aead, x->aead->alg_key,
801 (x->aead->alg_key_len + 7) / 8);
802 if (err)
803 goto error;
804
805 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8);
806 if (err)
807 goto error;
808
809 error:
810 return err;
811 }
812
813 static int esp_init_authenc(struct xfrm_state *x)
814 {
815 struct crypto_aead *aead;
816 struct crypto_authenc_key_param *param;
817 struct rtattr *rta;
818 char *key;
819 char *p;
820 char authenc_name[CRYPTO_MAX_ALG_NAME];
821 unsigned int keylen;
822 int err;
823 u32 mask = 0;
824
825 err = -EINVAL;
826 if (!x->ealg)
827 goto error;
828
829 err = -ENAMETOOLONG;
830
831 if ((x->props.flags & XFRM_STATE_ESN)) {
832 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
833 "%s%sauthencesn(%s,%s)%s",
834 x->geniv ?: "", x->geniv ? "(" : "",
835 x->aalg ? x->aalg->alg_name : "digest_null",
836 x->ealg->alg_name,
837 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
838 goto error;
839 } else {
840 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
841 "%s%sauthenc(%s,%s)%s",
842 x->geniv ?: "", x->geniv ? "(" : "",
843 x->aalg ? x->aalg->alg_name : "digest_null",
844 x->ealg->alg_name,
845 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
846 goto error;
847 }
848
849 if (x->xso.offload_handle)
850 mask |= CRYPTO_ALG_ASYNC;
851
852 aead = crypto_alloc_aead(authenc_name, 0, mask);
853 err = PTR_ERR(aead);
854 if (IS_ERR(aead))
855 goto error;
856
857 x->data = aead;
858
859 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) +
860 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param));
861 err = -ENOMEM;
862 key = kmalloc(keylen, GFP_KERNEL);
863 if (!key)
864 goto error;
865
866 p = key;
867 rta = (void *)p;
868 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
869 rta->rta_len = RTA_LENGTH(sizeof(*param));
870 param = RTA_DATA(rta);
871 p += RTA_SPACE(sizeof(*param));
872
873 if (x->aalg) {
874 struct xfrm_algo_desc *aalg_desc;
875
876 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8);
877 p += (x->aalg->alg_key_len + 7) / 8;
878
879 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
880 BUG_ON(!aalg_desc);
881
882 err = -EINVAL;
883 if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
884 crypto_aead_authsize(aead)) {
885 pr_info("ESP: %s digestsize %u != %hu\n",
886 x->aalg->alg_name,
887 crypto_aead_authsize(aead),
888 aalg_desc->uinfo.auth.icv_fullbits / 8);
889 goto free_key;
890 }
891
892 err = crypto_aead_setauthsize(
893 aead, x->aalg->alg_trunc_len / 8);
894 if (err)
895 goto free_key;
896 }
897
898 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
899 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
900
901 err = crypto_aead_setkey(aead, key, keylen);
902
903 free_key:
904 kfree(key);
905
906 error:
907 return err;
908 }
909
910 static int esp_init_state(struct xfrm_state *x)
911 {
912 struct crypto_aead *aead;
913 u32 align;
914 int err;
915
916 x->data = NULL;
917
918 if (x->aead)
919 err = esp_init_aead(x);
920 else
921 err = esp_init_authenc(x);
922
923 if (err)
924 goto error;
925
926 aead = x->data;
927
928 x->props.header_len = sizeof(struct ip_esp_hdr) +
929 crypto_aead_ivsize(aead);
930 if (x->props.mode == XFRM_MODE_TUNNEL)
931 x->props.header_len += sizeof(struct iphdr);
932 else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6)
933 x->props.header_len += IPV4_BEET_PHMAXLEN;
934 if (x->encap) {
935 struct xfrm_encap_tmpl *encap = x->encap;
936
937 switch (encap->encap_type) {
938 default:
939 goto error;
940 case UDP_ENCAP_ESPINUDP:
941 x->props.header_len += sizeof(struct udphdr);
942 break;
943 case UDP_ENCAP_ESPINUDP_NON_IKE:
944 x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32);
945 break;
946 }
947 }
948
949 align = ALIGN(crypto_aead_blocksize(aead), 4);
950 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead);
951
952 error:
953 return err;
954 }
955
956 static int esp4_rcv_cb(struct sk_buff *skb, int err)
957 {
958 return 0;
959 }
960
961 static const struct xfrm_type esp_type =
962 {
963 .description = "ESP4",
964 .owner = THIS_MODULE,
965 .proto = IPPROTO_ESP,
966 .flags = XFRM_TYPE_REPLAY_PROT,
967 .init_state = esp_init_state,
968 .destructor = esp_destroy,
969 .get_mtu = esp4_get_mtu,
970 .input = esp_input,
971 .output = esp_output,
972 };
973
974 static struct xfrm4_protocol esp4_protocol = {
975 .handler = xfrm4_rcv,
976 .input_handler = xfrm_input,
977 .cb_handler = esp4_rcv_cb,
978 .err_handler = esp4_err,
979 .priority = 0,
980 };
981
982 static int __init esp4_init(void)
983 {
984 if (xfrm_register_type(&esp_type, AF_INET) < 0) {
985 pr_info("%s: can't add xfrm type\n", __func__);
986 return -EAGAIN;
987 }
988 if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) {
989 pr_info("%s: can't add protocol\n", __func__);
990 xfrm_unregister_type(&esp_type, AF_INET);
991 return -EAGAIN;
992 }
993 return 0;
994 }
995
996 static void __exit esp4_fini(void)
997 {
998 if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0)
999 pr_info("%s: can't remove protocol\n", __func__);
1000 if (xfrm_unregister_type(&esp_type, AF_INET) < 0)
1001 pr_info("%s: can't remove xfrm type\n", __func__);
1002 }
1003
1004 module_init(esp4_init);
1005 module_exit(esp4_fini);
1006 MODULE_LICENSE("GPL");
1007 MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);
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