cpufreq: intel_pstate: Replace MSR_NHM_TURBO_RATIO_LIMIT
[linux/fpc-iii.git] / net / ipv4 / ah4.c
blobf2a71025a7705d5c7b10dc108440ee2ea5cd03aa
1 #define pr_fmt(fmt) "IPsec: " fmt
3 #include <crypto/hash.h>
4 #include <linux/err.h>
5 #include <linux/module.h>
6 #include <linux/slab.h>
7 #include <net/ip.h>
8 #include <net/xfrm.h>
9 #include <net/ah.h>
10 #include <linux/crypto.h>
11 #include <linux/pfkeyv2.h>
12 #include <linux/scatterlist.h>
13 #include <net/icmp.h>
14 #include <net/protocol.h>
16 struct ah_skb_cb {
17 struct xfrm_skb_cb xfrm;
18 void *tmp;
21 #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0]))
23 static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags,
24 unsigned int size)
26 unsigned int len;
28 len = size + crypto_ahash_digestsize(ahash) +
29 (crypto_ahash_alignmask(ahash) &
30 ~(crypto_tfm_ctx_alignment() - 1));
32 len = ALIGN(len, crypto_tfm_ctx_alignment());
34 len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash);
35 len = ALIGN(len, __alignof__(struct scatterlist));
37 len += sizeof(struct scatterlist) * nfrags;
39 return kmalloc(len, GFP_ATOMIC);
42 static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset)
44 return tmp + offset;
47 static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp,
48 unsigned int offset)
50 return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1);
53 static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash,
54 u8 *icv)
56 struct ahash_request *req;
58 req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash),
59 crypto_tfm_ctx_alignment());
61 ahash_request_set_tfm(req, ahash);
63 return req;
66 static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash,
67 struct ahash_request *req)
69 return (void *)ALIGN((unsigned long)(req + 1) +
70 crypto_ahash_reqsize(ahash),
71 __alignof__(struct scatterlist));
74 /* Clear mutable options and find final destination to substitute
75 * into IP header for icv calculation. Options are already checked
76 * for validity, so paranoia is not required. */
78 static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr)
80 unsigned char *optptr = (unsigned char *)(iph+1);
81 int l = iph->ihl*4 - sizeof(struct iphdr);
82 int optlen;
84 while (l > 0) {
85 switch (*optptr) {
86 case IPOPT_END:
87 return 0;
88 case IPOPT_NOOP:
89 l--;
90 optptr++;
91 continue;
93 optlen = optptr[1];
94 if (optlen<2 || optlen>l)
95 return -EINVAL;
96 switch (*optptr) {
97 case IPOPT_SEC:
98 case 0x85: /* Some "Extended Security" crap. */
99 case IPOPT_CIPSO:
100 case IPOPT_RA:
101 case 0x80|21: /* RFC1770 */
102 break;
103 case IPOPT_LSRR:
104 case IPOPT_SSRR:
105 if (optlen < 6)
106 return -EINVAL;
107 memcpy(daddr, optptr+optlen-4, 4);
108 /* Fall through */
109 default:
110 memset(optptr, 0, optlen);
112 l -= optlen;
113 optptr += optlen;
115 return 0;
118 static void ah_output_done(struct crypto_async_request *base, int err)
120 u8 *icv;
121 struct iphdr *iph;
122 struct sk_buff *skb = base->data;
123 struct xfrm_state *x = skb_dst(skb)->xfrm;
124 struct ah_data *ahp = x->data;
125 struct iphdr *top_iph = ip_hdr(skb);
126 struct ip_auth_hdr *ah = ip_auth_hdr(skb);
127 int ihl = ip_hdrlen(skb);
129 iph = AH_SKB_CB(skb)->tmp;
130 icv = ah_tmp_icv(ahp->ahash, iph, ihl);
131 memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
133 top_iph->tos = iph->tos;
134 top_iph->ttl = iph->ttl;
135 top_iph->frag_off = iph->frag_off;
136 if (top_iph->ihl != 5) {
137 top_iph->daddr = iph->daddr;
138 memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
141 kfree(AH_SKB_CB(skb)->tmp);
142 xfrm_output_resume(skb, err);
145 static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
147 int err;
148 int nfrags;
149 int ihl;
150 u8 *icv;
151 struct sk_buff *trailer;
152 struct crypto_ahash *ahash;
153 struct ahash_request *req;
154 struct scatterlist *sg;
155 struct iphdr *iph, *top_iph;
156 struct ip_auth_hdr *ah;
157 struct ah_data *ahp;
158 int seqhi_len = 0;
159 __be32 *seqhi;
160 int sglists = 0;
161 struct scatterlist *seqhisg;
163 ahp = x->data;
164 ahash = ahp->ahash;
166 if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
167 goto out;
168 nfrags = err;
170 skb_push(skb, -skb_network_offset(skb));
171 ah = ip_auth_hdr(skb);
172 ihl = ip_hdrlen(skb);
174 if (x->props.flags & XFRM_STATE_ESN) {
175 sglists = 1;
176 seqhi_len = sizeof(*seqhi);
178 err = -ENOMEM;
179 iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + seqhi_len);
180 if (!iph)
181 goto out;
182 seqhi = (__be32 *)((char *)iph + ihl);
183 icv = ah_tmp_icv(ahash, seqhi, seqhi_len);
184 req = ah_tmp_req(ahash, icv);
185 sg = ah_req_sg(ahash, req);
186 seqhisg = sg + nfrags;
188 memset(ah->auth_data, 0, ahp->icv_trunc_len);
190 top_iph = ip_hdr(skb);
192 iph->tos = top_iph->tos;
193 iph->ttl = top_iph->ttl;
194 iph->frag_off = top_iph->frag_off;
196 if (top_iph->ihl != 5) {
197 iph->daddr = top_iph->daddr;
198 memcpy(iph+1, top_iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
199 err = ip_clear_mutable_options(top_iph, &top_iph->daddr);
200 if (err)
201 goto out_free;
204 ah->nexthdr = *skb_mac_header(skb);
205 *skb_mac_header(skb) = IPPROTO_AH;
207 top_iph->tos = 0;
208 top_iph->tot_len = htons(skb->len);
209 top_iph->frag_off = 0;
210 top_iph->ttl = 0;
211 top_iph->check = 0;
213 if (x->props.flags & XFRM_STATE_ALIGN4)
214 ah->hdrlen = (XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
215 else
216 ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
218 ah->reserved = 0;
219 ah->spi = x->id.spi;
220 ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
222 sg_init_table(sg, nfrags + sglists);
223 skb_to_sgvec_nomark(skb, sg, 0, skb->len);
225 if (x->props.flags & XFRM_STATE_ESN) {
226 /* Attach seqhi sg right after packet payload */
227 *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
228 sg_set_buf(seqhisg, seqhi, seqhi_len);
230 ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len);
231 ahash_request_set_callback(req, 0, ah_output_done, skb);
233 AH_SKB_CB(skb)->tmp = iph;
235 err = crypto_ahash_digest(req);
236 if (err) {
237 if (err == -EINPROGRESS)
238 goto out;
240 if (err == -EBUSY)
241 err = NET_XMIT_DROP;
242 goto out_free;
245 memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
247 top_iph->tos = iph->tos;
248 top_iph->ttl = iph->ttl;
249 top_iph->frag_off = iph->frag_off;
250 if (top_iph->ihl != 5) {
251 top_iph->daddr = iph->daddr;
252 memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
255 out_free:
256 kfree(iph);
257 out:
258 return err;
261 static void ah_input_done(struct crypto_async_request *base, int err)
263 u8 *auth_data;
264 u8 *icv;
265 struct iphdr *work_iph;
266 struct sk_buff *skb = base->data;
267 struct xfrm_state *x = xfrm_input_state(skb);
268 struct ah_data *ahp = x->data;
269 struct ip_auth_hdr *ah = ip_auth_hdr(skb);
270 int ihl = ip_hdrlen(skb);
271 int ah_hlen = (ah->hdrlen + 2) << 2;
273 work_iph = AH_SKB_CB(skb)->tmp;
274 auth_data = ah_tmp_auth(work_iph, ihl);
275 icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len);
277 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
278 if (err)
279 goto out;
281 err = ah->nexthdr;
283 skb->network_header += ah_hlen;
284 memcpy(skb_network_header(skb), work_iph, ihl);
285 __skb_pull(skb, ah_hlen + ihl);
287 if (x->props.mode == XFRM_MODE_TUNNEL)
288 skb_reset_transport_header(skb);
289 else
290 skb_set_transport_header(skb, -ihl);
291 out:
292 kfree(AH_SKB_CB(skb)->tmp);
293 xfrm_input_resume(skb, err);
296 static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
298 int ah_hlen;
299 int ihl;
300 int nexthdr;
301 int nfrags;
302 u8 *auth_data;
303 u8 *icv;
304 struct sk_buff *trailer;
305 struct crypto_ahash *ahash;
306 struct ahash_request *req;
307 struct scatterlist *sg;
308 struct iphdr *iph, *work_iph;
309 struct ip_auth_hdr *ah;
310 struct ah_data *ahp;
311 int err = -ENOMEM;
312 int seqhi_len = 0;
313 __be32 *seqhi;
314 int sglists = 0;
315 struct scatterlist *seqhisg;
317 if (!pskb_may_pull(skb, sizeof(*ah)))
318 goto out;
320 ah = (struct ip_auth_hdr *)skb->data;
321 ahp = x->data;
322 ahash = ahp->ahash;
324 nexthdr = ah->nexthdr;
325 ah_hlen = (ah->hdrlen + 2) << 2;
327 if (x->props.flags & XFRM_STATE_ALIGN4) {
328 if (ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_full_len) &&
329 ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len))
330 goto out;
331 } else {
332 if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
333 ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
334 goto out;
337 if (!pskb_may_pull(skb, ah_hlen))
338 goto out;
340 /* We are going to _remove_ AH header to keep sockets happy,
341 * so... Later this can change. */
342 if (skb_unclone(skb, GFP_ATOMIC))
343 goto out;
345 skb->ip_summed = CHECKSUM_NONE;
348 if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
349 goto out;
350 nfrags = err;
352 ah = (struct ip_auth_hdr *)skb->data;
353 iph = ip_hdr(skb);
354 ihl = ip_hdrlen(skb);
356 if (x->props.flags & XFRM_STATE_ESN) {
357 sglists = 1;
358 seqhi_len = sizeof(*seqhi);
361 work_iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl +
362 ahp->icv_trunc_len + seqhi_len);
363 if (!work_iph) {
364 err = -ENOMEM;
365 goto out;
368 seqhi = (__be32 *)((char *)work_iph + ihl);
369 auth_data = ah_tmp_auth(seqhi, seqhi_len);
370 icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
371 req = ah_tmp_req(ahash, icv);
372 sg = ah_req_sg(ahash, req);
373 seqhisg = sg + nfrags;
375 memcpy(work_iph, iph, ihl);
376 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
377 memset(ah->auth_data, 0, ahp->icv_trunc_len);
379 iph->ttl = 0;
380 iph->tos = 0;
381 iph->frag_off = 0;
382 iph->check = 0;
383 if (ihl > sizeof(*iph)) {
384 __be32 dummy;
385 err = ip_clear_mutable_options(iph, &dummy);
386 if (err)
387 goto out_free;
390 skb_push(skb, ihl);
392 sg_init_table(sg, nfrags + sglists);
393 skb_to_sgvec_nomark(skb, sg, 0, skb->len);
395 if (x->props.flags & XFRM_STATE_ESN) {
396 /* Attach seqhi sg right after packet payload */
397 *seqhi = XFRM_SKB_CB(skb)->seq.input.hi;
398 sg_set_buf(seqhisg, seqhi, seqhi_len);
400 ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len);
401 ahash_request_set_callback(req, 0, ah_input_done, skb);
403 AH_SKB_CB(skb)->tmp = work_iph;
405 err = crypto_ahash_digest(req);
406 if (err) {
407 if (err == -EINPROGRESS)
408 goto out;
410 goto out_free;
413 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
414 if (err)
415 goto out_free;
417 skb->network_header += ah_hlen;
418 memcpy(skb_network_header(skb), work_iph, ihl);
419 __skb_pull(skb, ah_hlen + ihl);
420 if (x->props.mode == XFRM_MODE_TUNNEL)
421 skb_reset_transport_header(skb);
422 else
423 skb_set_transport_header(skb, -ihl);
425 err = nexthdr;
427 out_free:
428 kfree (work_iph);
429 out:
430 return err;
433 static int ah4_err(struct sk_buff *skb, u32 info)
435 struct net *net = dev_net(skb->dev);
436 const struct iphdr *iph = (const struct iphdr *)skb->data;
437 struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
438 struct xfrm_state *x;
440 switch (icmp_hdr(skb)->type) {
441 case ICMP_DEST_UNREACH:
442 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
443 return 0;
444 case ICMP_REDIRECT:
445 break;
446 default:
447 return 0;
450 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
451 ah->spi, IPPROTO_AH, AF_INET);
452 if (!x)
453 return 0;
455 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
456 ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_AH, 0);
457 else
458 ipv4_redirect(skb, net, 0, 0, IPPROTO_AH, 0);
459 xfrm_state_put(x);
461 return 0;
464 static int ah_init_state(struct xfrm_state *x)
466 struct ah_data *ahp = NULL;
467 struct xfrm_algo_desc *aalg_desc;
468 struct crypto_ahash *ahash;
470 if (!x->aalg)
471 goto error;
473 if (x->encap)
474 goto error;
476 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
477 if (!ahp)
478 return -ENOMEM;
480 ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
481 if (IS_ERR(ahash))
482 goto error;
484 ahp->ahash = ahash;
485 if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
486 (x->aalg->alg_key_len + 7) / 8))
487 goto error;
490 * Lookup the algorithm description maintained by xfrm_algo,
491 * verify crypto transform properties, and store information
492 * we need for AH processing. This lookup cannot fail here
493 * after a successful crypto_alloc_ahash().
495 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
496 BUG_ON(!aalg_desc);
498 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
499 crypto_ahash_digestsize(ahash)) {
500 pr_info("%s: %s digestsize %u != %hu\n",
501 __func__, x->aalg->alg_name,
502 crypto_ahash_digestsize(ahash),
503 aalg_desc->uinfo.auth.icv_fullbits / 8);
504 goto error;
507 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
508 ahp->icv_trunc_len = x->aalg->alg_trunc_len/8;
510 if (x->props.flags & XFRM_STATE_ALIGN4)
511 x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) +
512 ahp->icv_trunc_len);
513 else
514 x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
515 ahp->icv_trunc_len);
516 if (x->props.mode == XFRM_MODE_TUNNEL)
517 x->props.header_len += sizeof(struct iphdr);
518 x->data = ahp;
520 return 0;
522 error:
523 if (ahp) {
524 crypto_free_ahash(ahp->ahash);
525 kfree(ahp);
527 return -EINVAL;
530 static void ah_destroy(struct xfrm_state *x)
532 struct ah_data *ahp = x->data;
534 if (!ahp)
535 return;
537 crypto_free_ahash(ahp->ahash);
538 kfree(ahp);
541 static int ah4_rcv_cb(struct sk_buff *skb, int err)
543 return 0;
546 static const struct xfrm_type ah_type =
548 .description = "AH4",
549 .owner = THIS_MODULE,
550 .proto = IPPROTO_AH,
551 .flags = XFRM_TYPE_REPLAY_PROT,
552 .init_state = ah_init_state,
553 .destructor = ah_destroy,
554 .input = ah_input,
555 .output = ah_output
558 static struct xfrm4_protocol ah4_protocol = {
559 .handler = xfrm4_rcv,
560 .input_handler = xfrm_input,
561 .cb_handler = ah4_rcv_cb,
562 .err_handler = ah4_err,
563 .priority = 0,
566 static int __init ah4_init(void)
568 if (xfrm_register_type(&ah_type, AF_INET) < 0) {
569 pr_info("%s: can't add xfrm type\n", __func__);
570 return -EAGAIN;
572 if (xfrm4_protocol_register(&ah4_protocol, IPPROTO_AH) < 0) {
573 pr_info("%s: can't add protocol\n", __func__);
574 xfrm_unregister_type(&ah_type, AF_INET);
575 return -EAGAIN;
577 return 0;
580 static void __exit ah4_fini(void)
582 if (xfrm4_protocol_deregister(&ah4_protocol, IPPROTO_AH) < 0)
583 pr_info("%s: can't remove protocol\n", __func__);
584 if (xfrm_unregister_type(&ah_type, AF_INET) < 0)
585 pr_info("%s: can't remove xfrm type\n", __func__);
588 module_init(ah4_init);
589 module_exit(ah4_fini);
590 MODULE_LICENSE("GPL");
591 MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_AH);