109c434b8SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
2afd46503SJoe Perches #define pr_fmt(fmt) "IPsec: " fmt
3afd46503SJoe Perches
467df58a3SSabrina Dubroca #include <crypto/algapi.h>
5dff3bb06SSteffen Klassert #include <crypto/hash.h>
607d4ee58SHerbert Xu #include <linux/err.h>
71da177e4SLinus Torvalds #include <linux/module.h>
85a0e3ad6STejun Heo #include <linux/slab.h>
91da177e4SLinus Torvalds #include <net/ip.h>
101da177e4SLinus Torvalds #include <net/xfrm.h>
111da177e4SLinus Torvalds #include <net/ah.h>
121da177e4SLinus Torvalds #include <linux/crypto.h>
131da177e4SLinus Torvalds #include <linux/pfkeyv2.h>
14dff3bb06SSteffen Klassert #include <linux/scatterlist.h>
151da177e4SLinus Torvalds #include <net/icmp.h>
1614c85021SArnaldo Carvalho de Melo #include <net/protocol.h>
171da177e4SLinus Torvalds
18dff3bb06SSteffen Klassert struct ah_skb_cb {
19dff3bb06SSteffen Klassert struct xfrm_skb_cb xfrm;
20dff3bb06SSteffen Klassert void *tmp;
21dff3bb06SSteffen Klassert };
22dff3bb06SSteffen Klassert
23dff3bb06SSteffen Klassert #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0]))
24dff3bb06SSteffen Klassert
ah_alloc_tmp(struct crypto_ahash * ahash,int nfrags,unsigned int size)25dff3bb06SSteffen Klassert static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags,
26dff3bb06SSteffen Klassert unsigned int size)
27dff3bb06SSteffen Klassert {
28dff3bb06SSteffen Klassert unsigned int len;
29dff3bb06SSteffen Klassert
30dff3bb06SSteffen Klassert len = size + crypto_ahash_digestsize(ahash) +
31dff3bb06SSteffen Klassert (crypto_ahash_alignmask(ahash) &
32dff3bb06SSteffen Klassert ~(crypto_tfm_ctx_alignment() - 1));
33dff3bb06SSteffen Klassert
34dff3bb06SSteffen Klassert len = ALIGN(len, crypto_tfm_ctx_alignment());
35dff3bb06SSteffen Klassert
36dff3bb06SSteffen Klassert len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash);
37dff3bb06SSteffen Klassert len = ALIGN(len, __alignof__(struct scatterlist));
38dff3bb06SSteffen Klassert
39dff3bb06SSteffen Klassert len += sizeof(struct scatterlist) * nfrags;
40dff3bb06SSteffen Klassert
41dff3bb06SSteffen Klassert return kmalloc(len, GFP_ATOMIC);
42dff3bb06SSteffen Klassert }
43dff3bb06SSteffen Klassert
ah_tmp_auth(void * tmp,unsigned int offset)44dff3bb06SSteffen Klassert static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset)
45dff3bb06SSteffen Klassert {
46dff3bb06SSteffen Klassert return tmp + offset;
47dff3bb06SSteffen Klassert }
48dff3bb06SSteffen Klassert
ah_tmp_icv(struct crypto_ahash * ahash,void * tmp,unsigned int offset)49dff3bb06SSteffen Klassert static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp,
50dff3bb06SSteffen Klassert unsigned int offset)
51dff3bb06SSteffen Klassert {
52dff3bb06SSteffen Klassert return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1);
53dff3bb06SSteffen Klassert }
54dff3bb06SSteffen Klassert
ah_tmp_req(struct crypto_ahash * ahash,u8 * icv)55dff3bb06SSteffen Klassert static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash,
56dff3bb06SSteffen Klassert u8 *icv)
57dff3bb06SSteffen Klassert {
58dff3bb06SSteffen Klassert struct ahash_request *req;
59dff3bb06SSteffen Klassert
60dff3bb06SSteffen Klassert req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash),
61dff3bb06SSteffen Klassert crypto_tfm_ctx_alignment());
62dff3bb06SSteffen Klassert
63dff3bb06SSteffen Klassert ahash_request_set_tfm(req, ahash);
64dff3bb06SSteffen Klassert
65dff3bb06SSteffen Klassert return req;
66dff3bb06SSteffen Klassert }
67dff3bb06SSteffen Klassert
ah_req_sg(struct crypto_ahash * ahash,struct ahash_request * req)68dff3bb06SSteffen Klassert static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash,
69dff3bb06SSteffen Klassert struct ahash_request *req)
70dff3bb06SSteffen Klassert {
71dff3bb06SSteffen Klassert return (void *)ALIGN((unsigned long)(req + 1) +
72dff3bb06SSteffen Klassert crypto_ahash_reqsize(ahash),
73dff3bb06SSteffen Klassert __alignof__(struct scatterlist));
74dff3bb06SSteffen Klassert }
751da177e4SLinus Torvalds
761da177e4SLinus Torvalds /* Clear mutable options and find final destination to substitute
771da177e4SLinus Torvalds * into IP header for icv calculation. Options are already checked
781da177e4SLinus Torvalds * for validity, so paranoia is not required. */
791da177e4SLinus Torvalds
ip_clear_mutable_options(const struct iphdr * iph,__be32 * daddr)80b71d1d42SEric Dumazet static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr)
811da177e4SLinus Torvalds {
821da177e4SLinus Torvalds unsigned char *optptr = (unsigned char *)(iph+1);
831da177e4SLinus Torvalds int l = iph->ihl*4 - sizeof(struct iphdr);
841da177e4SLinus Torvalds int optlen;
851da177e4SLinus Torvalds
861da177e4SLinus Torvalds while (l > 0) {
871da177e4SLinus Torvalds switch (*optptr) {
881da177e4SLinus Torvalds case IPOPT_END:
891da177e4SLinus Torvalds return 0;
901da177e4SLinus Torvalds case IPOPT_NOOP:
911da177e4SLinus Torvalds l--;
921da177e4SLinus Torvalds optptr++;
931da177e4SLinus Torvalds continue;
941da177e4SLinus Torvalds }
951da177e4SLinus Torvalds optlen = optptr[1];
961da177e4SLinus Torvalds if (optlen<2 || optlen>l)
971da177e4SLinus Torvalds return -EINVAL;
981da177e4SLinus Torvalds switch (*optptr) {
991da177e4SLinus Torvalds case IPOPT_SEC:
1001da177e4SLinus Torvalds case 0x85: /* Some "Extended Security" crap. */
10111a03f78SPaul Moore case IPOPT_CIPSO:
1021da177e4SLinus Torvalds case IPOPT_RA:
1031da177e4SLinus Torvalds case 0x80|21: /* RFC1770 */
1041da177e4SLinus Torvalds break;
1051da177e4SLinus Torvalds case IPOPT_LSRR:
1061da177e4SLinus Torvalds case IPOPT_SSRR:
1071da177e4SLinus Torvalds if (optlen < 6)
1081da177e4SLinus Torvalds return -EINVAL;
1091da177e4SLinus Torvalds memcpy(daddr, optptr+optlen-4, 4);
110a8eceea8SJoe Perches fallthrough;
1111da177e4SLinus Torvalds default:
11296fe1c02SNick Bowler memset(optptr, 0, optlen);
1131da177e4SLinus Torvalds }
1141da177e4SLinus Torvalds l -= optlen;
1151da177e4SLinus Torvalds optptr += optlen;
1161da177e4SLinus Torvalds }
1171da177e4SLinus Torvalds return 0;
1181da177e4SLinus Torvalds }
1191da177e4SLinus Torvalds
ah_output_done(void * data,int err)120*fd5dabf7SHerbert Xu static void ah_output_done(void *data, int err)
121dff3bb06SSteffen Klassert {
122dff3bb06SSteffen Klassert u8 *icv;
123dff3bb06SSteffen Klassert struct iphdr *iph;
124*fd5dabf7SHerbert Xu struct sk_buff *skb = data;
125dff3bb06SSteffen Klassert struct xfrm_state *x = skb_dst(skb)->xfrm;
126dff3bb06SSteffen Klassert struct ah_data *ahp = x->data;
127dff3bb06SSteffen Klassert struct iphdr *top_iph = ip_hdr(skb);
128dff3bb06SSteffen Klassert struct ip_auth_hdr *ah = ip_auth_hdr(skb);
129dff3bb06SSteffen Klassert int ihl = ip_hdrlen(skb);
130dff3bb06SSteffen Klassert
131dff3bb06SSteffen Klassert iph = AH_SKB_CB(skb)->tmp;
132dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahp->ahash, iph, ihl);
133dff3bb06SSteffen Klassert memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
134dff3bb06SSteffen Klassert
135dff3bb06SSteffen Klassert top_iph->tos = iph->tos;
136dff3bb06SSteffen Klassert top_iph->ttl = iph->ttl;
137dff3bb06SSteffen Klassert top_iph->frag_off = iph->frag_off;
138dff3bb06SSteffen Klassert if (top_iph->ihl != 5) {
139dff3bb06SSteffen Klassert top_iph->daddr = iph->daddr;
140dff3bb06SSteffen Klassert memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
141dff3bb06SSteffen Klassert }
142dff3bb06SSteffen Klassert
143dff3bb06SSteffen Klassert kfree(AH_SKB_CB(skb)->tmp);
1449ab1265dSEvan Nimmo xfrm_output_resume(skb->sk, skb, err);
145dff3bb06SSteffen Klassert }
146dff3bb06SSteffen Klassert
ah_output(struct xfrm_state * x,struct sk_buff * skb)1471da177e4SLinus Torvalds static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
1481da177e4SLinus Torvalds {
1491da177e4SLinus Torvalds int err;
150dff3bb06SSteffen Klassert int nfrags;
151dff3bb06SSteffen Klassert int ihl;
152dff3bb06SSteffen Klassert u8 *icv;
153dff3bb06SSteffen Klassert struct sk_buff *trailer;
154dff3bb06SSteffen Klassert struct crypto_ahash *ahash;
155dff3bb06SSteffen Klassert struct ahash_request *req;
156dff3bb06SSteffen Klassert struct scatterlist *sg;
1571da177e4SLinus Torvalds struct iphdr *iph, *top_iph;
1581da177e4SLinus Torvalds struct ip_auth_hdr *ah;
1591da177e4SLinus Torvalds struct ah_data *ahp;
160d4d573d0SFan Du int seqhi_len = 0;
161d4d573d0SFan Du __be32 *seqhi;
162d4d573d0SFan Du int sglists = 0;
163d4d573d0SFan Du struct scatterlist *seqhisg;
164dff3bb06SSteffen Klassert
165dff3bb06SSteffen Klassert ahp = x->data;
166dff3bb06SSteffen Klassert ahash = ahp->ahash;
167dff3bb06SSteffen Klassert
168dff3bb06SSteffen Klassert if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
169dff3bb06SSteffen Klassert goto out;
170dff3bb06SSteffen Klassert nfrags = err;
1711da177e4SLinus Torvalds
1727b277b1aSHerbert Xu skb_push(skb, -skb_network_offset(skb));
173dff3bb06SSteffen Klassert ah = ip_auth_hdr(skb);
174dff3bb06SSteffen Klassert ihl = ip_hdrlen(skb);
175dff3bb06SSteffen Klassert
176d4d573d0SFan Du if (x->props.flags & XFRM_STATE_ESN) {
177d4d573d0SFan Du sglists = 1;
178d4d573d0SFan Du seqhi_len = sizeof(*seqhi);
179d4d573d0SFan Du }
180dff3bb06SSteffen Klassert err = -ENOMEM;
181d4d573d0SFan Du iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + seqhi_len);
182dff3bb06SSteffen Klassert if (!iph)
183dff3bb06SSteffen Klassert goto out;
184d4d573d0SFan Du seqhi = (__be32 *)((char *)iph + ihl);
185d4d573d0SFan Du icv = ah_tmp_icv(ahash, seqhi, seqhi_len);
186dff3bb06SSteffen Klassert req = ah_tmp_req(ahash, icv);
187dff3bb06SSteffen Klassert sg = ah_req_sg(ahash, req);
188d4d573d0SFan Du seqhisg = sg + nfrags;
189dff3bb06SSteffen Klassert
190dff3bb06SSteffen Klassert memset(ah->auth_data, 0, ahp->icv_trunc_len);
191dff3bb06SSteffen Klassert
192eddc9ec5SArnaldo Carvalho de Melo top_iph = ip_hdr(skb);
1931da177e4SLinus Torvalds
1941da177e4SLinus Torvalds iph->tos = top_iph->tos;
1951da177e4SLinus Torvalds iph->ttl = top_iph->ttl;
1961da177e4SLinus Torvalds iph->frag_off = top_iph->frag_off;
1971da177e4SLinus Torvalds
1981da177e4SLinus Torvalds if (top_iph->ihl != 5) {
1991da177e4SLinus Torvalds iph->daddr = top_iph->daddr;
2001da177e4SLinus Torvalds memcpy(iph+1, top_iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
2011da177e4SLinus Torvalds err = ip_clear_mutable_options(top_iph, &top_iph->daddr);
2021da177e4SLinus Torvalds if (err)
203dff3bb06SSteffen Klassert goto out_free;
2041da177e4SLinus Torvalds }
2051da177e4SLinus Torvalds
20637fedd3aSHerbert Xu ah->nexthdr = *skb_mac_header(skb);
20737fedd3aSHerbert Xu *skb_mac_header(skb) = IPPROTO_AH;
2081da177e4SLinus Torvalds
2091da177e4SLinus Torvalds top_iph->tos = 0;
2101da177e4SLinus Torvalds top_iph->tot_len = htons(skb->len);
2111da177e4SLinus Torvalds top_iph->frag_off = 0;
2121da177e4SLinus Torvalds top_iph->ttl = 0;
2131da177e4SLinus Torvalds top_iph->check = 0;
2141da177e4SLinus Torvalds
215fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4)
216fa9921e4SNicolas Dichtel ah->hdrlen = (XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
217fa9921e4SNicolas Dichtel else
21887bdc48dSHerbert Xu ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
2191da177e4SLinus Torvalds
2201da177e4SLinus Torvalds ah->reserved = 0;
2211da177e4SLinus Torvalds ah->spi = x->id.spi;
2221ce3644aSSteffen Klassert ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
223b7c6538cSHerbert Xu
224d4d573d0SFan Du sg_init_table(sg, nfrags + sglists);
2253f297707SJason A. Donenfeld err = skb_to_sgvec_nomark(skb, sg, 0, skb->len);
2263f297707SJason A. Donenfeld if (unlikely(err < 0))
2273f297707SJason A. Donenfeld goto out_free;
228b7c6538cSHerbert Xu
229d4d573d0SFan Du if (x->props.flags & XFRM_STATE_ESN) {
230d4d573d0SFan Du /* Attach seqhi sg right after packet payload */
231d4d573d0SFan Du *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
232d4d573d0SFan Du sg_set_buf(seqhisg, seqhi, seqhi_len);
233d4d573d0SFan Du }
234d4d573d0SFan Du ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len);
235dff3bb06SSteffen Klassert ahash_request_set_callback(req, 0, ah_output_done, skb);
236dff3bb06SSteffen Klassert
237dff3bb06SSteffen Klassert AH_SKB_CB(skb)->tmp = iph;
238dff3bb06SSteffen Klassert
239dff3bb06SSteffen Klassert err = crypto_ahash_digest(req);
240dff3bb06SSteffen Klassert if (err) {
241dff3bb06SSteffen Klassert if (err == -EINPROGRESS)
242dff3bb06SSteffen Klassert goto out;
243dff3bb06SSteffen Klassert
244068c2e70SGilad Ben-Yossef if (err == -ENOSPC)
245dff3bb06SSteffen Klassert err = NET_XMIT_DROP;
246dff3bb06SSteffen Klassert goto out_free;
247dff3bb06SSteffen Klassert }
248dff3bb06SSteffen Klassert
249dff3bb06SSteffen Klassert memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
2501da177e4SLinus Torvalds
2511da177e4SLinus Torvalds top_iph->tos = iph->tos;
2521da177e4SLinus Torvalds top_iph->ttl = iph->ttl;
2531da177e4SLinus Torvalds top_iph->frag_off = iph->frag_off;
2541da177e4SLinus Torvalds if (top_iph->ihl != 5) {
2551da177e4SLinus Torvalds top_iph->daddr = iph->daddr;
2561da177e4SLinus Torvalds memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
2571da177e4SLinus Torvalds }
2581da177e4SLinus Torvalds
259dff3bb06SSteffen Klassert out_free:
260dff3bb06SSteffen Klassert kfree(iph);
261dff3bb06SSteffen Klassert out:
2621da177e4SLinus Torvalds return err;
2631da177e4SLinus Torvalds }
2641da177e4SLinus Torvalds
ah_input_done(void * data,int err)265*fd5dabf7SHerbert Xu static void ah_input_done(void *data, int err)
266dff3bb06SSteffen Klassert {
267dff3bb06SSteffen Klassert u8 *auth_data;
268dff3bb06SSteffen Klassert u8 *icv;
269dff3bb06SSteffen Klassert struct iphdr *work_iph;
270*fd5dabf7SHerbert Xu struct sk_buff *skb = data;
271dff3bb06SSteffen Klassert struct xfrm_state *x = xfrm_input_state(skb);
272dff3bb06SSteffen Klassert struct ah_data *ahp = x->data;
273dff3bb06SSteffen Klassert struct ip_auth_hdr *ah = ip_auth_hdr(skb);
274dff3bb06SSteffen Klassert int ihl = ip_hdrlen(skb);
275dff3bb06SSteffen Klassert int ah_hlen = (ah->hdrlen + 2) << 2;
276dff3bb06SSteffen Klassert
277ebd89a2dSGilad Ben-Yossef if (err)
278ebd89a2dSGilad Ben-Yossef goto out;
279ebd89a2dSGilad Ben-Yossef
280dff3bb06SSteffen Klassert work_iph = AH_SKB_CB(skb)->tmp;
281dff3bb06SSteffen Klassert auth_data = ah_tmp_auth(work_iph, ihl);
282dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len);
283dff3bb06SSteffen Klassert
28467df58a3SSabrina Dubroca err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0;
285dff3bb06SSteffen Klassert if (err)
286dff3bb06SSteffen Klassert goto out;
287dff3bb06SSteffen Klassert
288b7ea81a5SNick Bowler err = ah->nexthdr;
289b7ea81a5SNick Bowler
290dff3bb06SSteffen Klassert skb->network_header += ah_hlen;
291dff3bb06SSteffen Klassert memcpy(skb_network_header(skb), work_iph, ihl);
292dff3bb06SSteffen Klassert __skb_pull(skb, ah_hlen + ihl);
2937143dfacSLi RongQing
2947143dfacSLi RongQing if (x->props.mode == XFRM_MODE_TUNNEL)
2957143dfacSLi RongQing skb_reset_transport_header(skb);
2967143dfacSLi RongQing else
297dff3bb06SSteffen Klassert skb_set_transport_header(skb, -ihl);
298dff3bb06SSteffen Klassert out:
299dff3bb06SSteffen Klassert kfree(AH_SKB_CB(skb)->tmp);
300dff3bb06SSteffen Klassert xfrm_input_resume(skb, err);
301dff3bb06SSteffen Klassert }
302dff3bb06SSteffen Klassert
ah_input(struct xfrm_state * x,struct sk_buff * skb)303e695633eSHerbert Xu static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
3041da177e4SLinus Torvalds {
3051da177e4SLinus Torvalds int ah_hlen;
30631a4ab93SHerbert Xu int ihl;
307631a6698SHerbert Xu int nexthdr;
308dff3bb06SSteffen Klassert int nfrags;
309dff3bb06SSteffen Klassert u8 *auth_data;
310dff3bb06SSteffen Klassert u8 *icv;
311dff3bb06SSteffen Klassert struct sk_buff *trailer;
312dff3bb06SSteffen Klassert struct crypto_ahash *ahash;
313dff3bb06SSteffen Klassert struct ahash_request *req;
314dff3bb06SSteffen Klassert struct scatterlist *sg;
315dff3bb06SSteffen Klassert struct iphdr *iph, *work_iph;
3161da177e4SLinus Torvalds struct ip_auth_hdr *ah;
3171da177e4SLinus Torvalds struct ah_data *ahp;
318dff3bb06SSteffen Klassert int err = -ENOMEM;
319d8b2a860SFan Du int seqhi_len = 0;
320d8b2a860SFan Du __be32 *seqhi;
321d8b2a860SFan Du int sglists = 0;
322d8b2a860SFan Du struct scatterlist *seqhisg;
3231da177e4SLinus Torvalds
32487bdc48dSHerbert Xu if (!pskb_may_pull(skb, sizeof(*ah)))
3251da177e4SLinus Torvalds goto out;
3261da177e4SLinus Torvalds
3271da177e4SLinus Torvalds ah = (struct ip_auth_hdr *)skb->data;
3281da177e4SLinus Torvalds ahp = x->data;
329dff3bb06SSteffen Klassert ahash = ahp->ahash;
330dff3bb06SSteffen Klassert
331631a6698SHerbert Xu nexthdr = ah->nexthdr;
3321da177e4SLinus Torvalds ah_hlen = (ah->hdrlen + 2) << 2;
3331da177e4SLinus Torvalds
334fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4) {
335fa9921e4SNicolas Dichtel if (ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_full_len) &&
336fa9921e4SNicolas Dichtel ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len))
337fa9921e4SNicolas Dichtel goto out;
338fa9921e4SNicolas Dichtel } else {
33987bdc48dSHerbert Xu if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
34087bdc48dSHerbert Xu ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
3411da177e4SLinus Torvalds goto out;
342fa9921e4SNicolas Dichtel }
3431da177e4SLinus Torvalds
3441da177e4SLinus Torvalds if (!pskb_may_pull(skb, ah_hlen))
3451da177e4SLinus Torvalds goto out;
3461da177e4SLinus Torvalds
3471da177e4SLinus Torvalds /* We are going to _remove_ AH header to keep sockets happy,
3481da177e4SLinus Torvalds * so... Later this can change. */
34914bbd6a5SPravin B Shelar if (skb_unclone(skb, GFP_ATOMIC))
3501da177e4SLinus Torvalds goto out;
3511da177e4SLinus Torvalds
3521da177e4SLinus Torvalds skb->ip_summed = CHECKSUM_NONE;
3531da177e4SLinus Torvalds
3541da177e4SLinus Torvalds
355dff3bb06SSteffen Klassert if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
356dff3bb06SSteffen Klassert goto out;
357dff3bb06SSteffen Klassert nfrags = err;
358dff3bb06SSteffen Klassert
3594b0ef1f2SDang Hongwu ah = (struct ip_auth_hdr *)skb->data;
3604b0ef1f2SDang Hongwu iph = ip_hdr(skb);
3614b0ef1f2SDang Hongwu ihl = ip_hdrlen(skb);
3624b0ef1f2SDang Hongwu
363d8b2a860SFan Du if (x->props.flags & XFRM_STATE_ESN) {
364d8b2a860SFan Du sglists = 1;
365d8b2a860SFan Du seqhi_len = sizeof(*seqhi);
366d8b2a860SFan Du }
367d8b2a860SFan Du
368d8b2a860SFan Du work_iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl +
369d8b2a860SFan Du ahp->icv_trunc_len + seqhi_len);
37094c10f0eSDavid S. Miller if (!work_iph) {
37194c10f0eSDavid S. Miller err = -ENOMEM;
372dff3bb06SSteffen Klassert goto out;
37394c10f0eSDavid S. Miller }
374dff3bb06SSteffen Klassert
375d8b2a860SFan Du seqhi = (__be32 *)((char *)work_iph + ihl);
376d8b2a860SFan Du auth_data = ah_tmp_auth(seqhi, seqhi_len);
377dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
378dff3bb06SSteffen Klassert req = ah_tmp_req(ahash, icv);
379dff3bb06SSteffen Klassert sg = ah_req_sg(ahash, req);
380d8b2a860SFan Du seqhisg = sg + nfrags;
381dff3bb06SSteffen Klassert
382dff3bb06SSteffen Klassert memcpy(work_iph, iph, ihl);
383dff3bb06SSteffen Klassert memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
384dff3bb06SSteffen Klassert memset(ah->auth_data, 0, ahp->icv_trunc_len);
3851da177e4SLinus Torvalds
3861da177e4SLinus Torvalds iph->ttl = 0;
3871da177e4SLinus Torvalds iph->tos = 0;
3881da177e4SLinus Torvalds iph->frag_off = 0;
3891da177e4SLinus Torvalds iph->check = 0;
39031a4ab93SHerbert Xu if (ihl > sizeof(*iph)) {
391d5a0a1e3SAl Viro __be32 dummy;
392dff3bb06SSteffen Klassert err = ip_clear_mutable_options(iph, &dummy);
393dff3bb06SSteffen Klassert if (err)
394dff3bb06SSteffen Klassert goto out_free;
3951da177e4SLinus Torvalds }
3960ebea8efSHerbert Xu
39731a4ab93SHerbert Xu skb_push(skb, ihl);
3980ebea8efSHerbert Xu
399d8b2a860SFan Du sg_init_table(sg, nfrags + sglists);
4003f297707SJason A. Donenfeld err = skb_to_sgvec_nomark(skb, sg, 0, skb->len);
4013f297707SJason A. Donenfeld if (unlikely(err < 0))
4023f297707SJason A. Donenfeld goto out_free;
403dff3bb06SSteffen Klassert
404d8b2a860SFan Du if (x->props.flags & XFRM_STATE_ESN) {
405d8b2a860SFan Du /* Attach seqhi sg right after packet payload */
406d8b2a860SFan Du *seqhi = XFRM_SKB_CB(skb)->seq.input.hi;
407d8b2a860SFan Du sg_set_buf(seqhisg, seqhi, seqhi_len);
408d8b2a860SFan Du }
409d8b2a860SFan Du ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len);
410dff3bb06SSteffen Klassert ahash_request_set_callback(req, 0, ah_input_done, skb);
411dff3bb06SSteffen Klassert
412dff3bb06SSteffen Klassert AH_SKB_CB(skb)->tmp = work_iph;
413dff3bb06SSteffen Klassert
414dff3bb06SSteffen Klassert err = crypto_ahash_digest(req);
415dff3bb06SSteffen Klassert if (err) {
416dff3bb06SSteffen Klassert if (err == -EINPROGRESS)
4171da177e4SLinus Torvalds goto out;
4180ebea8efSHerbert Xu
419dff3bb06SSteffen Klassert goto out_free;
420dff3bb06SSteffen Klassert }
421dff3bb06SSteffen Klassert
42267df58a3SSabrina Dubroca err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0;
423dff3bb06SSteffen Klassert if (err)
424dff3bb06SSteffen Klassert goto out_free;
425dff3bb06SSteffen Klassert
426b0e380b1SArnaldo Carvalho de Melo skb->network_header += ah_hlen;
427dff3bb06SSteffen Klassert memcpy(skb_network_header(skb), work_iph, ihl);
42831a4ab93SHerbert Xu __skb_pull(skb, ah_hlen + ihl);
4297143dfacSLi RongQing if (x->props.mode == XFRM_MODE_TUNNEL)
4307143dfacSLi RongQing skb_reset_transport_header(skb);
4317143dfacSLi RongQing else
432dff3bb06SSteffen Klassert skb_set_transport_header(skb, -ihl);
4331da177e4SLinus Torvalds
434dff3bb06SSteffen Klassert err = nexthdr;
4351da177e4SLinus Torvalds
436dff3bb06SSteffen Klassert out_free:
437dff3bb06SSteffen Klassert kfree (work_iph);
4381da177e4SLinus Torvalds out:
43907d4ee58SHerbert Xu return err;
4401da177e4SLinus Torvalds }
4411da177e4SLinus Torvalds
ah4_err(struct sk_buff * skb,u32 info)442e5b56454SSteffen Klassert static int ah4_err(struct sk_buff *skb, u32 info)
4431da177e4SLinus Torvalds {
4444fb236baSAlexey Dobriyan struct net *net = dev_net(skb->dev);
445b71d1d42SEric Dumazet const struct iphdr *iph = (const struct iphdr *)skb->data;
4461da177e4SLinus Torvalds struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
4471da177e4SLinus Torvalds struct xfrm_state *x;
4481da177e4SLinus Torvalds
44955be7a9cSDavid S. Miller switch (icmp_hdr(skb)->type) {
45055be7a9cSDavid S. Miller case ICMP_DEST_UNREACH:
45155be7a9cSDavid S. Miller if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
452e5b56454SSteffen Klassert return 0;
45379121184SGustavo A. R. Silva break;
45455be7a9cSDavid S. Miller case ICMP_REDIRECT:
45555be7a9cSDavid S. Miller break;
45655be7a9cSDavid S. Miller default:
457e5b56454SSteffen Klassert return 0;
45855be7a9cSDavid S. Miller }
4591da177e4SLinus Torvalds
460b71d1d42SEric Dumazet x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
461b71d1d42SEric Dumazet ah->spi, IPPROTO_AH, AF_INET);
4621da177e4SLinus Torvalds if (!x)
463e5b56454SSteffen Klassert return 0;
46455be7a9cSDavid S. Miller
465387aa65aSTimo Teräs if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
466d888f396SMaciej Żenczykowski ipv4_update_pmtu(skb, net, info, 0, IPPROTO_AH);
467387aa65aSTimo Teräs else
4681042caa7SMaciej Żenczykowski ipv4_redirect(skb, net, 0, IPPROTO_AH);
4691da177e4SLinus Torvalds xfrm_state_put(x);
470e5b56454SSteffen Klassert
471e5b56454SSteffen Klassert return 0;
4721da177e4SLinus Torvalds }
4731da177e4SLinus Torvalds
ah_init_state(struct xfrm_state * x,struct netlink_ext_ack * extack)474e1e10b44SSabrina Dubroca static int ah_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
4751da177e4SLinus Torvalds {
4761da177e4SLinus Torvalds struct ah_data *ahp = NULL;
4771da177e4SLinus Torvalds struct xfrm_algo_desc *aalg_desc;
478dff3bb06SSteffen Klassert struct crypto_ahash *ahash;
4791da177e4SLinus Torvalds
480ef87a4f8SSabrina Dubroca if (!x->aalg) {
481ef87a4f8SSabrina Dubroca NL_SET_ERR_MSG(extack, "AH requires a state with an AUTH algorithm");
4821da177e4SLinus Torvalds goto error;
483ef87a4f8SSabrina Dubroca }
4841da177e4SLinus Torvalds
485ef87a4f8SSabrina Dubroca if (x->encap) {
486ef87a4f8SSabrina Dubroca NL_SET_ERR_MSG(extack, "AH is not compatible with encapsulation");
4871da177e4SLinus Torvalds goto error;
488ef87a4f8SSabrina Dubroca }
4891da177e4SLinus Torvalds
4900da974f4SPanagiotis Issaris ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
491dff3bb06SSteffen Klassert if (!ahp)
4921da177e4SLinus Torvalds return -ENOMEM;
4931da177e4SLinus Torvalds
494dff3bb06SSteffen Klassert ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
495ef87a4f8SSabrina Dubroca if (IS_ERR(ahash)) {
496ef87a4f8SSabrina Dubroca NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
4971da177e4SLinus Torvalds goto error;
498ef87a4f8SSabrina Dubroca }
49907d4ee58SHerbert Xu
500dff3bb06SSteffen Klassert ahp->ahash = ahash;
501dff3bb06SSteffen Klassert if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
502ef87a4f8SSabrina Dubroca (x->aalg->alg_key_len + 7) / 8)) {
503ef87a4f8SSabrina Dubroca NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
50407d4ee58SHerbert Xu goto error;
505ef87a4f8SSabrina Dubroca }
5061da177e4SLinus Torvalds
5071da177e4SLinus Torvalds /*
5081da177e4SLinus Torvalds * Lookup the algorithm description maintained by xfrm_algo,
5091da177e4SLinus Torvalds * verify crypto transform properties, and store information
5101da177e4SLinus Torvalds * we need for AH processing. This lookup cannot fail here
511dff3bb06SSteffen Klassert * after a successful crypto_alloc_ahash().
5121da177e4SLinus Torvalds */
5131da177e4SLinus Torvalds aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
5141da177e4SLinus Torvalds BUG_ON(!aalg_desc);
5151da177e4SLinus Torvalds
5161da177e4SLinus Torvalds if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
517dff3bb06SSteffen Klassert crypto_ahash_digestsize(ahash)) {
518ef87a4f8SSabrina Dubroca NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations");
5191da177e4SLinus Torvalds goto error;
5201da177e4SLinus Torvalds }
5211da177e4SLinus Torvalds
5221da177e4SLinus Torvalds ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
5238f8a088cSMartin Willi ahp->icv_trunc_len = x->aalg->alg_trunc_len/8;
5241da177e4SLinus Torvalds
525fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4)
526fa9921e4SNicolas Dichtel x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) +
527fa9921e4SNicolas Dichtel ahp->icv_trunc_len);
528fa9921e4SNicolas Dichtel else
52987bdc48dSHerbert Xu x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
53087bdc48dSHerbert Xu ahp->icv_trunc_len);
5317e49e6deSMasahide NAKAMURA if (x->props.mode == XFRM_MODE_TUNNEL)
5321da177e4SLinus Torvalds x->props.header_len += sizeof(struct iphdr);
5331da177e4SLinus Torvalds x->data = ahp;
5341da177e4SLinus Torvalds
5351da177e4SLinus Torvalds return 0;
5361da177e4SLinus Torvalds
5371da177e4SLinus Torvalds error:
5381da177e4SLinus Torvalds if (ahp) {
539dff3bb06SSteffen Klassert crypto_free_ahash(ahp->ahash);
5401da177e4SLinus Torvalds kfree(ahp);
5411da177e4SLinus Torvalds }
5421da177e4SLinus Torvalds return -EINVAL;
5431da177e4SLinus Torvalds }
5441da177e4SLinus Torvalds
ah_destroy(struct xfrm_state * x)5451da177e4SLinus Torvalds static void ah_destroy(struct xfrm_state *x)
5461da177e4SLinus Torvalds {
5471da177e4SLinus Torvalds struct ah_data *ahp = x->data;
5481da177e4SLinus Torvalds
5491da177e4SLinus Torvalds if (!ahp)
5501da177e4SLinus Torvalds return;
5511da177e4SLinus Torvalds
552dff3bb06SSteffen Klassert crypto_free_ahash(ahp->ahash);
5531da177e4SLinus Torvalds kfree(ahp);
5541da177e4SLinus Torvalds }
5551da177e4SLinus Torvalds
ah4_rcv_cb(struct sk_buff * skb,int err)556e5b56454SSteffen Klassert static int ah4_rcv_cb(struct sk_buff *skb, int err)
557e5b56454SSteffen Klassert {
558e5b56454SSteffen Klassert return 0;
559e5b56454SSteffen Klassert }
5601da177e4SLinus Torvalds
561533cb5b0SEric Dumazet static const struct xfrm_type ah_type =
5621da177e4SLinus Torvalds {
5631da177e4SLinus Torvalds .owner = THIS_MODULE,
5641da177e4SLinus Torvalds .proto = IPPROTO_AH,
565436a0a40SHerbert Xu .flags = XFRM_TYPE_REPLAY_PROT,
5661da177e4SLinus Torvalds .init_state = ah_init_state,
5671da177e4SLinus Torvalds .destructor = ah_destroy,
5681da177e4SLinus Torvalds .input = ah_input,
5691da177e4SLinus Torvalds .output = ah_output
5701da177e4SLinus Torvalds };
5711da177e4SLinus Torvalds
572e5b56454SSteffen Klassert static struct xfrm4_protocol ah4_protocol = {
5731da177e4SLinus Torvalds .handler = xfrm4_rcv,
574e5b56454SSteffen Klassert .input_handler = xfrm_input,
575e5b56454SSteffen Klassert .cb_handler = ah4_rcv_cb,
5761da177e4SLinus Torvalds .err_handler = ah4_err,
577e5b56454SSteffen Klassert .priority = 0,
5781da177e4SLinus Torvalds };
5791da177e4SLinus Torvalds
ah4_init(void)5801da177e4SLinus Torvalds static int __init ah4_init(void)
5811da177e4SLinus Torvalds {
5821da177e4SLinus Torvalds if (xfrm_register_type(&ah_type, AF_INET) < 0) {
583058bd4d2SJoe Perches pr_info("%s: can't add xfrm type\n", __func__);
5841da177e4SLinus Torvalds return -EAGAIN;
5851da177e4SLinus Torvalds }
586e5b56454SSteffen Klassert if (xfrm4_protocol_register(&ah4_protocol, IPPROTO_AH) < 0) {
587058bd4d2SJoe Perches pr_info("%s: can't add protocol\n", __func__);
5881da177e4SLinus Torvalds xfrm_unregister_type(&ah_type, AF_INET);
5891da177e4SLinus Torvalds return -EAGAIN;
5901da177e4SLinus Torvalds }
5911da177e4SLinus Torvalds return 0;
5921da177e4SLinus Torvalds }
5931da177e4SLinus Torvalds
ah4_fini(void)5941da177e4SLinus Torvalds static void __exit ah4_fini(void)
5951da177e4SLinus Torvalds {
596e5b56454SSteffen Klassert if (xfrm4_protocol_deregister(&ah4_protocol, IPPROTO_AH) < 0)
597058bd4d2SJoe Perches pr_info("%s: can't remove protocol\n", __func__);
5984f518e80SFlorian Westphal xfrm_unregister_type(&ah_type, AF_INET);
5991da177e4SLinus Torvalds }
6001da177e4SLinus Torvalds
6011da177e4SLinus Torvalds module_init(ah4_init);
6021da177e4SLinus Torvalds module_exit(ah4_fini);
6031da177e4SLinus Torvalds MODULE_LICENSE("GPL");
604d3d6dd3aSMasahide NAKAMURA MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_AH);
605