1afd46503SJoe Perches #define pr_fmt(fmt) "IPsec: " fmt 2afd46503SJoe Perches 367df58a3SSabrina Dubroca #include <crypto/algapi.h> 4dff3bb06SSteffen Klassert #include <crypto/hash.h> 507d4ee58SHerbert Xu #include <linux/err.h> 61da177e4SLinus Torvalds #include <linux/module.h> 75a0e3ad6STejun Heo #include <linux/slab.h> 81da177e4SLinus Torvalds #include <net/ip.h> 91da177e4SLinus Torvalds #include <net/xfrm.h> 101da177e4SLinus Torvalds #include <net/ah.h> 111da177e4SLinus Torvalds #include <linux/crypto.h> 121da177e4SLinus Torvalds #include <linux/pfkeyv2.h> 13dff3bb06SSteffen Klassert #include <linux/scatterlist.h> 141da177e4SLinus Torvalds #include <net/icmp.h> 1514c85021SArnaldo Carvalho de Melo #include <net/protocol.h> 161da177e4SLinus Torvalds 17dff3bb06SSteffen Klassert struct ah_skb_cb { 18dff3bb06SSteffen Klassert struct xfrm_skb_cb xfrm; 19dff3bb06SSteffen Klassert void *tmp; 20dff3bb06SSteffen Klassert }; 21dff3bb06SSteffen Klassert 22dff3bb06SSteffen Klassert #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) 23dff3bb06SSteffen Klassert 24dff3bb06SSteffen Klassert static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, 25dff3bb06SSteffen Klassert unsigned int size) 26dff3bb06SSteffen Klassert { 27dff3bb06SSteffen Klassert unsigned int len; 28dff3bb06SSteffen Klassert 29dff3bb06SSteffen Klassert len = size + crypto_ahash_digestsize(ahash) + 30dff3bb06SSteffen Klassert (crypto_ahash_alignmask(ahash) & 31dff3bb06SSteffen Klassert ~(crypto_tfm_ctx_alignment() - 1)); 32dff3bb06SSteffen Klassert 33dff3bb06SSteffen Klassert len = ALIGN(len, crypto_tfm_ctx_alignment()); 34dff3bb06SSteffen Klassert 35dff3bb06SSteffen Klassert len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); 36dff3bb06SSteffen Klassert len = ALIGN(len, __alignof__(struct scatterlist)); 37dff3bb06SSteffen Klassert 38dff3bb06SSteffen Klassert len += sizeof(struct scatterlist) * nfrags; 39dff3bb06SSteffen Klassert 40dff3bb06SSteffen Klassert return kmalloc(len, GFP_ATOMIC); 41dff3bb06SSteffen Klassert } 42dff3bb06SSteffen Klassert 43dff3bb06SSteffen Klassert static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset) 44dff3bb06SSteffen Klassert { 45dff3bb06SSteffen Klassert return tmp + offset; 46dff3bb06SSteffen Klassert } 47dff3bb06SSteffen Klassert 48dff3bb06SSteffen Klassert static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, 49dff3bb06SSteffen Klassert unsigned int offset) 50dff3bb06SSteffen Klassert { 51dff3bb06SSteffen Klassert return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); 52dff3bb06SSteffen Klassert } 53dff3bb06SSteffen Klassert 54dff3bb06SSteffen Klassert static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, 55dff3bb06SSteffen Klassert u8 *icv) 56dff3bb06SSteffen Klassert { 57dff3bb06SSteffen Klassert struct ahash_request *req; 58dff3bb06SSteffen Klassert 59dff3bb06SSteffen Klassert req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), 60dff3bb06SSteffen Klassert crypto_tfm_ctx_alignment()); 61dff3bb06SSteffen Klassert 62dff3bb06SSteffen Klassert ahash_request_set_tfm(req, ahash); 63dff3bb06SSteffen Klassert 64dff3bb06SSteffen Klassert return req; 65dff3bb06SSteffen Klassert } 66dff3bb06SSteffen Klassert 67dff3bb06SSteffen Klassert static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, 68dff3bb06SSteffen Klassert struct ahash_request *req) 69dff3bb06SSteffen Klassert { 70dff3bb06SSteffen Klassert return (void *)ALIGN((unsigned long)(req + 1) + 71dff3bb06SSteffen Klassert crypto_ahash_reqsize(ahash), 72dff3bb06SSteffen Klassert __alignof__(struct scatterlist)); 73dff3bb06SSteffen Klassert } 741da177e4SLinus Torvalds 751da177e4SLinus Torvalds /* Clear mutable options and find final destination to substitute 761da177e4SLinus Torvalds * into IP header for icv calculation. Options are already checked 771da177e4SLinus Torvalds * for validity, so paranoia is not required. */ 781da177e4SLinus Torvalds 79b71d1d42SEric Dumazet static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr) 801da177e4SLinus Torvalds { 811da177e4SLinus Torvalds unsigned char *optptr = (unsigned char *)(iph+1); 821da177e4SLinus Torvalds int l = iph->ihl*4 - sizeof(struct iphdr); 831da177e4SLinus Torvalds int optlen; 841da177e4SLinus Torvalds 851da177e4SLinus Torvalds while (l > 0) { 861da177e4SLinus Torvalds switch (*optptr) { 871da177e4SLinus Torvalds case IPOPT_END: 881da177e4SLinus Torvalds return 0; 891da177e4SLinus Torvalds case IPOPT_NOOP: 901da177e4SLinus Torvalds l--; 911da177e4SLinus Torvalds optptr++; 921da177e4SLinus Torvalds continue; 931da177e4SLinus Torvalds } 941da177e4SLinus Torvalds optlen = optptr[1]; 951da177e4SLinus Torvalds if (optlen<2 || optlen>l) 961da177e4SLinus Torvalds return -EINVAL; 971da177e4SLinus Torvalds switch (*optptr) { 981da177e4SLinus Torvalds case IPOPT_SEC: 991da177e4SLinus Torvalds case 0x85: /* Some "Extended Security" crap. */ 10011a03f78SPaul Moore case IPOPT_CIPSO: 1011da177e4SLinus Torvalds case IPOPT_RA: 1021da177e4SLinus Torvalds case 0x80|21: /* RFC1770 */ 1031da177e4SLinus Torvalds break; 1041da177e4SLinus Torvalds case IPOPT_LSRR: 1051da177e4SLinus Torvalds case IPOPT_SSRR: 1061da177e4SLinus Torvalds if (optlen < 6) 1071da177e4SLinus Torvalds return -EINVAL; 1081da177e4SLinus Torvalds memcpy(daddr, optptr+optlen-4, 4); 1091da177e4SLinus Torvalds /* Fall through */ 1101da177e4SLinus Torvalds default: 11196fe1c02SNick Bowler memset(optptr, 0, optlen); 1121da177e4SLinus Torvalds } 1131da177e4SLinus Torvalds l -= optlen; 1141da177e4SLinus Torvalds optptr += optlen; 1151da177e4SLinus Torvalds } 1161da177e4SLinus Torvalds return 0; 1171da177e4SLinus Torvalds } 1181da177e4SLinus Torvalds 119dff3bb06SSteffen Klassert static void ah_output_done(struct crypto_async_request *base, int err) 120dff3bb06SSteffen Klassert { 121dff3bb06SSteffen Klassert u8 *icv; 122dff3bb06SSteffen Klassert struct iphdr *iph; 123dff3bb06SSteffen Klassert struct sk_buff *skb = base->data; 124dff3bb06SSteffen Klassert struct xfrm_state *x = skb_dst(skb)->xfrm; 125dff3bb06SSteffen Klassert struct ah_data *ahp = x->data; 126dff3bb06SSteffen Klassert struct iphdr *top_iph = ip_hdr(skb); 127dff3bb06SSteffen Klassert struct ip_auth_hdr *ah = ip_auth_hdr(skb); 128dff3bb06SSteffen Klassert int ihl = ip_hdrlen(skb); 129dff3bb06SSteffen Klassert 130dff3bb06SSteffen Klassert iph = AH_SKB_CB(skb)->tmp; 131dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahp->ahash, iph, ihl); 132dff3bb06SSteffen Klassert memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 133dff3bb06SSteffen Klassert 134dff3bb06SSteffen Klassert top_iph->tos = iph->tos; 135dff3bb06SSteffen Klassert top_iph->ttl = iph->ttl; 136dff3bb06SSteffen Klassert top_iph->frag_off = iph->frag_off; 137dff3bb06SSteffen Klassert if (top_iph->ihl != 5) { 138dff3bb06SSteffen Klassert top_iph->daddr = iph->daddr; 139dff3bb06SSteffen Klassert memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); 140dff3bb06SSteffen Klassert } 141dff3bb06SSteffen Klassert 142dff3bb06SSteffen Klassert kfree(AH_SKB_CB(skb)->tmp); 143dff3bb06SSteffen Klassert xfrm_output_resume(skb, err); 144dff3bb06SSteffen Klassert } 145dff3bb06SSteffen Klassert 1461da177e4SLinus Torvalds static int ah_output(struct xfrm_state *x, struct sk_buff *skb) 1471da177e4SLinus Torvalds { 1481da177e4SLinus Torvalds int err; 149dff3bb06SSteffen Klassert int nfrags; 150dff3bb06SSteffen Klassert int ihl; 151dff3bb06SSteffen Klassert u8 *icv; 152dff3bb06SSteffen Klassert struct sk_buff *trailer; 153dff3bb06SSteffen Klassert struct crypto_ahash *ahash; 154dff3bb06SSteffen Klassert struct ahash_request *req; 155dff3bb06SSteffen Klassert struct scatterlist *sg; 1561da177e4SLinus Torvalds struct iphdr *iph, *top_iph; 1571da177e4SLinus Torvalds struct ip_auth_hdr *ah; 1581da177e4SLinus Torvalds struct ah_data *ahp; 159d4d573d0SFan Du int seqhi_len = 0; 160d4d573d0SFan Du __be32 *seqhi; 161d4d573d0SFan Du int sglists = 0; 162d4d573d0SFan Du struct scatterlist *seqhisg; 163dff3bb06SSteffen Klassert 164dff3bb06SSteffen Klassert ahp = x->data; 165dff3bb06SSteffen Klassert ahash = ahp->ahash; 166dff3bb06SSteffen Klassert 167dff3bb06SSteffen Klassert if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 168dff3bb06SSteffen Klassert goto out; 169dff3bb06SSteffen Klassert nfrags = err; 1701da177e4SLinus Torvalds 1717b277b1aSHerbert Xu skb_push(skb, -skb_network_offset(skb)); 172dff3bb06SSteffen Klassert ah = ip_auth_hdr(skb); 173dff3bb06SSteffen Klassert ihl = ip_hdrlen(skb); 174dff3bb06SSteffen Klassert 175d4d573d0SFan Du if (x->props.flags & XFRM_STATE_ESN) { 176d4d573d0SFan Du sglists = 1; 177d4d573d0SFan Du seqhi_len = sizeof(*seqhi); 178d4d573d0SFan Du } 179dff3bb06SSteffen Klassert err = -ENOMEM; 180d4d573d0SFan Du iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + seqhi_len); 181dff3bb06SSteffen Klassert if (!iph) 182dff3bb06SSteffen Klassert goto out; 183d4d573d0SFan Du seqhi = (__be32 *)((char *)iph + ihl); 184d4d573d0SFan Du icv = ah_tmp_icv(ahash, seqhi, seqhi_len); 185dff3bb06SSteffen Klassert req = ah_tmp_req(ahash, icv); 186dff3bb06SSteffen Klassert sg = ah_req_sg(ahash, req); 187d4d573d0SFan Du seqhisg = sg + nfrags; 188dff3bb06SSteffen Klassert 189dff3bb06SSteffen Klassert memset(ah->auth_data, 0, ahp->icv_trunc_len); 190dff3bb06SSteffen Klassert 191eddc9ec5SArnaldo Carvalho de Melo top_iph = ip_hdr(skb); 1921da177e4SLinus Torvalds 1931da177e4SLinus Torvalds iph->tos = top_iph->tos; 1941da177e4SLinus Torvalds iph->ttl = top_iph->ttl; 1951da177e4SLinus Torvalds iph->frag_off = top_iph->frag_off; 1961da177e4SLinus Torvalds 1971da177e4SLinus Torvalds if (top_iph->ihl != 5) { 1981da177e4SLinus Torvalds iph->daddr = top_iph->daddr; 1991da177e4SLinus Torvalds memcpy(iph+1, top_iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); 2001da177e4SLinus Torvalds err = ip_clear_mutable_options(top_iph, &top_iph->daddr); 2011da177e4SLinus Torvalds if (err) 202dff3bb06SSteffen Klassert goto out_free; 2031da177e4SLinus Torvalds } 2041da177e4SLinus Torvalds 20537fedd3aSHerbert Xu ah->nexthdr = *skb_mac_header(skb); 20637fedd3aSHerbert Xu *skb_mac_header(skb) = IPPROTO_AH; 2071da177e4SLinus Torvalds 2081da177e4SLinus Torvalds top_iph->tos = 0; 2091da177e4SLinus Torvalds top_iph->tot_len = htons(skb->len); 2101da177e4SLinus Torvalds top_iph->frag_off = 0; 2111da177e4SLinus Torvalds top_iph->ttl = 0; 2121da177e4SLinus Torvalds top_iph->check = 0; 2131da177e4SLinus Torvalds 214fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4) 215fa9921e4SNicolas Dichtel ah->hdrlen = (XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; 216fa9921e4SNicolas Dichtel else 21787bdc48dSHerbert Xu ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; 2181da177e4SLinus Torvalds 2191da177e4SLinus Torvalds ah->reserved = 0; 2201da177e4SLinus Torvalds ah->spi = x->id.spi; 2211ce3644aSSteffen Klassert ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 222b7c6538cSHerbert Xu 223d4d573d0SFan Du sg_init_table(sg, nfrags + sglists); 224d4d573d0SFan Du skb_to_sgvec_nomark(skb, sg, 0, skb->len); 225b7c6538cSHerbert Xu 226d4d573d0SFan Du if (x->props.flags & XFRM_STATE_ESN) { 227d4d573d0SFan Du /* Attach seqhi sg right after packet payload */ 228d4d573d0SFan Du *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); 229d4d573d0SFan Du sg_set_buf(seqhisg, seqhi, seqhi_len); 230d4d573d0SFan Du } 231d4d573d0SFan Du ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len); 232dff3bb06SSteffen Klassert ahash_request_set_callback(req, 0, ah_output_done, skb); 233dff3bb06SSteffen Klassert 234dff3bb06SSteffen Klassert AH_SKB_CB(skb)->tmp = iph; 235dff3bb06SSteffen Klassert 236dff3bb06SSteffen Klassert err = crypto_ahash_digest(req); 237dff3bb06SSteffen Klassert if (err) { 238dff3bb06SSteffen Klassert if (err == -EINPROGRESS) 239dff3bb06SSteffen Klassert goto out; 240dff3bb06SSteffen Klassert 241dff3bb06SSteffen Klassert if (err == -EBUSY) 242dff3bb06SSteffen Klassert err = NET_XMIT_DROP; 243dff3bb06SSteffen Klassert goto out_free; 244dff3bb06SSteffen Klassert } 245dff3bb06SSteffen Klassert 246dff3bb06SSteffen Klassert memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 2471da177e4SLinus Torvalds 2481da177e4SLinus Torvalds top_iph->tos = iph->tos; 2491da177e4SLinus Torvalds top_iph->ttl = iph->ttl; 2501da177e4SLinus Torvalds top_iph->frag_off = iph->frag_off; 2511da177e4SLinus Torvalds if (top_iph->ihl != 5) { 2521da177e4SLinus Torvalds top_iph->daddr = iph->daddr; 2531da177e4SLinus Torvalds memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); 2541da177e4SLinus Torvalds } 2551da177e4SLinus Torvalds 256dff3bb06SSteffen Klassert out_free: 257dff3bb06SSteffen Klassert kfree(iph); 258dff3bb06SSteffen Klassert out: 2591da177e4SLinus Torvalds return err; 2601da177e4SLinus Torvalds } 2611da177e4SLinus Torvalds 262dff3bb06SSteffen Klassert static void ah_input_done(struct crypto_async_request *base, int err) 263dff3bb06SSteffen Klassert { 264dff3bb06SSteffen Klassert u8 *auth_data; 265dff3bb06SSteffen Klassert u8 *icv; 266dff3bb06SSteffen Klassert struct iphdr *work_iph; 267dff3bb06SSteffen Klassert struct sk_buff *skb = base->data; 268dff3bb06SSteffen Klassert struct xfrm_state *x = xfrm_input_state(skb); 269dff3bb06SSteffen Klassert struct ah_data *ahp = x->data; 270dff3bb06SSteffen Klassert struct ip_auth_hdr *ah = ip_auth_hdr(skb); 271dff3bb06SSteffen Klassert int ihl = ip_hdrlen(skb); 272dff3bb06SSteffen Klassert int ah_hlen = (ah->hdrlen + 2) << 2; 273dff3bb06SSteffen Klassert 274ebd89a2dSGilad Ben-Yossef if (err) 275ebd89a2dSGilad Ben-Yossef goto out; 276ebd89a2dSGilad Ben-Yossef 277dff3bb06SSteffen Klassert work_iph = AH_SKB_CB(skb)->tmp; 278dff3bb06SSteffen Klassert auth_data = ah_tmp_auth(work_iph, ihl); 279dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len); 280dff3bb06SSteffen Klassert 28167df58a3SSabrina Dubroca err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0; 282dff3bb06SSteffen Klassert if (err) 283dff3bb06SSteffen Klassert goto out; 284dff3bb06SSteffen Klassert 285b7ea81a5SNick Bowler err = ah->nexthdr; 286b7ea81a5SNick Bowler 287dff3bb06SSteffen Klassert skb->network_header += ah_hlen; 288dff3bb06SSteffen Klassert memcpy(skb_network_header(skb), work_iph, ihl); 289dff3bb06SSteffen Klassert __skb_pull(skb, ah_hlen + ihl); 2907143dfacSLi RongQing 2917143dfacSLi RongQing if (x->props.mode == XFRM_MODE_TUNNEL) 2927143dfacSLi RongQing skb_reset_transport_header(skb); 2937143dfacSLi RongQing else 294dff3bb06SSteffen Klassert skb_set_transport_header(skb, -ihl); 295dff3bb06SSteffen Klassert out: 296dff3bb06SSteffen Klassert kfree(AH_SKB_CB(skb)->tmp); 297dff3bb06SSteffen Klassert xfrm_input_resume(skb, err); 298dff3bb06SSteffen Klassert } 299dff3bb06SSteffen Klassert 300e695633eSHerbert Xu static int ah_input(struct xfrm_state *x, struct sk_buff *skb) 3011da177e4SLinus Torvalds { 3021da177e4SLinus Torvalds int ah_hlen; 30331a4ab93SHerbert Xu int ihl; 304631a6698SHerbert Xu int nexthdr; 305dff3bb06SSteffen Klassert int nfrags; 306dff3bb06SSteffen Klassert u8 *auth_data; 307dff3bb06SSteffen Klassert u8 *icv; 308dff3bb06SSteffen Klassert struct sk_buff *trailer; 309dff3bb06SSteffen Klassert struct crypto_ahash *ahash; 310dff3bb06SSteffen Klassert struct ahash_request *req; 311dff3bb06SSteffen Klassert struct scatterlist *sg; 312dff3bb06SSteffen Klassert struct iphdr *iph, *work_iph; 3131da177e4SLinus Torvalds struct ip_auth_hdr *ah; 3141da177e4SLinus Torvalds struct ah_data *ahp; 315dff3bb06SSteffen Klassert int err = -ENOMEM; 316d8b2a860SFan Du int seqhi_len = 0; 317d8b2a860SFan Du __be32 *seqhi; 318d8b2a860SFan Du int sglists = 0; 319d8b2a860SFan Du struct scatterlist *seqhisg; 3201da177e4SLinus Torvalds 32187bdc48dSHerbert Xu if (!pskb_may_pull(skb, sizeof(*ah))) 3221da177e4SLinus Torvalds goto out; 3231da177e4SLinus Torvalds 3241da177e4SLinus Torvalds ah = (struct ip_auth_hdr *)skb->data; 3251da177e4SLinus Torvalds ahp = x->data; 326dff3bb06SSteffen Klassert ahash = ahp->ahash; 327dff3bb06SSteffen Klassert 328631a6698SHerbert Xu nexthdr = ah->nexthdr; 3291da177e4SLinus Torvalds ah_hlen = (ah->hdrlen + 2) << 2; 3301da177e4SLinus Torvalds 331fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4) { 332fa9921e4SNicolas Dichtel if (ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_full_len) && 333fa9921e4SNicolas Dichtel ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len)) 334fa9921e4SNicolas Dichtel goto out; 335fa9921e4SNicolas Dichtel } else { 33687bdc48dSHerbert Xu if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && 33787bdc48dSHerbert Xu ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) 3381da177e4SLinus Torvalds goto out; 339fa9921e4SNicolas Dichtel } 3401da177e4SLinus Torvalds 3411da177e4SLinus Torvalds if (!pskb_may_pull(skb, ah_hlen)) 3421da177e4SLinus Torvalds goto out; 3431da177e4SLinus Torvalds 3441da177e4SLinus Torvalds /* We are going to _remove_ AH header to keep sockets happy, 3451da177e4SLinus Torvalds * so... Later this can change. */ 34614bbd6a5SPravin B Shelar if (skb_unclone(skb, GFP_ATOMIC)) 3471da177e4SLinus Torvalds goto out; 3481da177e4SLinus Torvalds 3491da177e4SLinus Torvalds skb->ip_summed = CHECKSUM_NONE; 3501da177e4SLinus Torvalds 3511da177e4SLinus Torvalds 352dff3bb06SSteffen Klassert if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 353dff3bb06SSteffen Klassert goto out; 354dff3bb06SSteffen Klassert nfrags = err; 355dff3bb06SSteffen Klassert 3564b0ef1f2SDang Hongwu ah = (struct ip_auth_hdr *)skb->data; 3574b0ef1f2SDang Hongwu iph = ip_hdr(skb); 3584b0ef1f2SDang Hongwu ihl = ip_hdrlen(skb); 3594b0ef1f2SDang Hongwu 360d8b2a860SFan Du if (x->props.flags & XFRM_STATE_ESN) { 361d8b2a860SFan Du sglists = 1; 362d8b2a860SFan Du seqhi_len = sizeof(*seqhi); 363d8b2a860SFan Du } 364d8b2a860SFan Du 365d8b2a860SFan Du work_iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + 366d8b2a860SFan Du ahp->icv_trunc_len + seqhi_len); 36794c10f0eSDavid S. Miller if (!work_iph) { 36894c10f0eSDavid S. Miller err = -ENOMEM; 369dff3bb06SSteffen Klassert goto out; 37094c10f0eSDavid S. Miller } 371dff3bb06SSteffen Klassert 372d8b2a860SFan Du seqhi = (__be32 *)((char *)work_iph + ihl); 373d8b2a860SFan Du auth_data = ah_tmp_auth(seqhi, seqhi_len); 374dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len); 375dff3bb06SSteffen Klassert req = ah_tmp_req(ahash, icv); 376dff3bb06SSteffen Klassert sg = ah_req_sg(ahash, req); 377d8b2a860SFan Du seqhisg = sg + nfrags; 378dff3bb06SSteffen Klassert 379dff3bb06SSteffen Klassert memcpy(work_iph, iph, ihl); 380dff3bb06SSteffen Klassert memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); 381dff3bb06SSteffen Klassert memset(ah->auth_data, 0, ahp->icv_trunc_len); 3821da177e4SLinus Torvalds 3831da177e4SLinus Torvalds iph->ttl = 0; 3841da177e4SLinus Torvalds iph->tos = 0; 3851da177e4SLinus Torvalds iph->frag_off = 0; 3861da177e4SLinus Torvalds iph->check = 0; 38731a4ab93SHerbert Xu if (ihl > sizeof(*iph)) { 388d5a0a1e3SAl Viro __be32 dummy; 389dff3bb06SSteffen Klassert err = ip_clear_mutable_options(iph, &dummy); 390dff3bb06SSteffen Klassert if (err) 391dff3bb06SSteffen Klassert goto out_free; 3921da177e4SLinus Torvalds } 3930ebea8efSHerbert Xu 39431a4ab93SHerbert Xu skb_push(skb, ihl); 3950ebea8efSHerbert Xu 396d8b2a860SFan Du sg_init_table(sg, nfrags + sglists); 397d8b2a860SFan Du skb_to_sgvec_nomark(skb, sg, 0, skb->len); 398dff3bb06SSteffen Klassert 399d8b2a860SFan Du if (x->props.flags & XFRM_STATE_ESN) { 400d8b2a860SFan Du /* Attach seqhi sg right after packet payload */ 401d8b2a860SFan Du *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; 402d8b2a860SFan Du sg_set_buf(seqhisg, seqhi, seqhi_len); 403d8b2a860SFan Du } 404d8b2a860SFan Du ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len); 405dff3bb06SSteffen Klassert ahash_request_set_callback(req, 0, ah_input_done, skb); 406dff3bb06SSteffen Klassert 407dff3bb06SSteffen Klassert AH_SKB_CB(skb)->tmp = work_iph; 408dff3bb06SSteffen Klassert 409dff3bb06SSteffen Klassert err = crypto_ahash_digest(req); 410dff3bb06SSteffen Klassert if (err) { 411dff3bb06SSteffen Klassert if (err == -EINPROGRESS) 4121da177e4SLinus Torvalds goto out; 4130ebea8efSHerbert Xu 414dff3bb06SSteffen Klassert goto out_free; 415dff3bb06SSteffen Klassert } 416dff3bb06SSteffen Klassert 41767df58a3SSabrina Dubroca err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0; 418dff3bb06SSteffen Klassert if (err) 419dff3bb06SSteffen Klassert goto out_free; 420dff3bb06SSteffen Klassert 421b0e380b1SArnaldo Carvalho de Melo skb->network_header += ah_hlen; 422dff3bb06SSteffen Klassert memcpy(skb_network_header(skb), work_iph, ihl); 42331a4ab93SHerbert Xu __skb_pull(skb, ah_hlen + ihl); 4247143dfacSLi RongQing if (x->props.mode == XFRM_MODE_TUNNEL) 4257143dfacSLi RongQing skb_reset_transport_header(skb); 4267143dfacSLi RongQing else 427dff3bb06SSteffen Klassert skb_set_transport_header(skb, -ihl); 4281da177e4SLinus Torvalds 429dff3bb06SSteffen Klassert err = nexthdr; 4301da177e4SLinus Torvalds 431dff3bb06SSteffen Klassert out_free: 432dff3bb06SSteffen Klassert kfree (work_iph); 4331da177e4SLinus Torvalds out: 43407d4ee58SHerbert Xu return err; 4351da177e4SLinus Torvalds } 4361da177e4SLinus Torvalds 437e5b56454SSteffen Klassert static int ah4_err(struct sk_buff *skb, u32 info) 4381da177e4SLinus Torvalds { 4394fb236baSAlexey Dobriyan struct net *net = dev_net(skb->dev); 440b71d1d42SEric Dumazet const struct iphdr *iph = (const struct iphdr *)skb->data; 4411da177e4SLinus Torvalds struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); 4421da177e4SLinus Torvalds struct xfrm_state *x; 4431da177e4SLinus Torvalds 44455be7a9cSDavid S. Miller switch (icmp_hdr(skb)->type) { 44555be7a9cSDavid S. Miller case ICMP_DEST_UNREACH: 44655be7a9cSDavid S. Miller if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) 447e5b56454SSteffen Klassert return 0; 44855be7a9cSDavid S. Miller case ICMP_REDIRECT: 44955be7a9cSDavid S. Miller break; 45055be7a9cSDavid S. Miller default: 451e5b56454SSteffen Klassert return 0; 45255be7a9cSDavid S. Miller } 4531da177e4SLinus Torvalds 454b71d1d42SEric Dumazet x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 455b71d1d42SEric Dumazet ah->spi, IPPROTO_AH, AF_INET); 4561da177e4SLinus Torvalds if (!x) 457e5b56454SSteffen Klassert return 0; 45855be7a9cSDavid S. Miller 459387aa65aSTimo Teräs if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) 46036393395SDavid S. Miller ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_AH, 0); 461387aa65aSTimo Teräs else 46255be7a9cSDavid S. Miller ipv4_redirect(skb, net, 0, 0, IPPROTO_AH, 0); 4631da177e4SLinus Torvalds xfrm_state_put(x); 464e5b56454SSteffen Klassert 465e5b56454SSteffen Klassert return 0; 4661da177e4SLinus Torvalds } 4671da177e4SLinus Torvalds 46872cb6962SHerbert Xu static int ah_init_state(struct xfrm_state *x) 4691da177e4SLinus Torvalds { 4701da177e4SLinus Torvalds struct ah_data *ahp = NULL; 4711da177e4SLinus Torvalds struct xfrm_algo_desc *aalg_desc; 472dff3bb06SSteffen Klassert struct crypto_ahash *ahash; 4731da177e4SLinus Torvalds 4741da177e4SLinus Torvalds if (!x->aalg) 4751da177e4SLinus Torvalds goto error; 4761da177e4SLinus Torvalds 4771da177e4SLinus Torvalds if (x->encap) 4781da177e4SLinus Torvalds goto error; 4791da177e4SLinus Torvalds 4800da974f4SPanagiotis Issaris ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); 481dff3bb06SSteffen Klassert if (!ahp) 4821da177e4SLinus Torvalds return -ENOMEM; 4831da177e4SLinus Torvalds 484dff3bb06SSteffen Klassert ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); 485dff3bb06SSteffen Klassert if (IS_ERR(ahash)) 4861da177e4SLinus Torvalds goto error; 48707d4ee58SHerbert Xu 488dff3bb06SSteffen Klassert ahp->ahash = ahash; 489dff3bb06SSteffen Klassert if (crypto_ahash_setkey(ahash, x->aalg->alg_key, 490bc31d3b2SHerbert Xu (x->aalg->alg_key_len + 7) / 8)) 49107d4ee58SHerbert Xu goto error; 4921da177e4SLinus Torvalds 4931da177e4SLinus Torvalds /* 4941da177e4SLinus Torvalds * Lookup the algorithm description maintained by xfrm_algo, 4951da177e4SLinus Torvalds * verify crypto transform properties, and store information 4961da177e4SLinus Torvalds * we need for AH processing. This lookup cannot fail here 497dff3bb06SSteffen Klassert * after a successful crypto_alloc_ahash(). 4981da177e4SLinus Torvalds */ 4991da177e4SLinus Torvalds aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 5001da177e4SLinus Torvalds BUG_ON(!aalg_desc); 5011da177e4SLinus Torvalds 5021da177e4SLinus Torvalds if (aalg_desc->uinfo.auth.icv_fullbits/8 != 503dff3bb06SSteffen Klassert crypto_ahash_digestsize(ahash)) { 504afd46503SJoe Perches pr_info("%s: %s digestsize %u != %hu\n", 505afd46503SJoe Perches __func__, x->aalg->alg_name, 506afd46503SJoe Perches crypto_ahash_digestsize(ahash), 5071da177e4SLinus Torvalds aalg_desc->uinfo.auth.icv_fullbits / 8); 5081da177e4SLinus Torvalds goto error; 5091da177e4SLinus Torvalds } 5101da177e4SLinus Torvalds 5111da177e4SLinus Torvalds ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; 5128f8a088cSMartin Willi ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; 5131da177e4SLinus Torvalds 514fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4) 515fa9921e4SNicolas Dichtel x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) + 516fa9921e4SNicolas Dichtel ahp->icv_trunc_len); 517fa9921e4SNicolas Dichtel else 51887bdc48dSHerbert Xu x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + 51987bdc48dSHerbert Xu ahp->icv_trunc_len); 5207e49e6deSMasahide NAKAMURA if (x->props.mode == XFRM_MODE_TUNNEL) 5211da177e4SLinus Torvalds x->props.header_len += sizeof(struct iphdr); 5221da177e4SLinus Torvalds x->data = ahp; 5231da177e4SLinus Torvalds 5241da177e4SLinus Torvalds return 0; 5251da177e4SLinus Torvalds 5261da177e4SLinus Torvalds error: 5271da177e4SLinus Torvalds if (ahp) { 528dff3bb06SSteffen Klassert crypto_free_ahash(ahp->ahash); 5291da177e4SLinus Torvalds kfree(ahp); 5301da177e4SLinus Torvalds } 5311da177e4SLinus Torvalds return -EINVAL; 5321da177e4SLinus Torvalds } 5331da177e4SLinus Torvalds 5341da177e4SLinus Torvalds static void ah_destroy(struct xfrm_state *x) 5351da177e4SLinus Torvalds { 5361da177e4SLinus Torvalds struct ah_data *ahp = x->data; 5371da177e4SLinus Torvalds 5381da177e4SLinus Torvalds if (!ahp) 5391da177e4SLinus Torvalds return; 5401da177e4SLinus Torvalds 541dff3bb06SSteffen Klassert crypto_free_ahash(ahp->ahash); 5421da177e4SLinus Torvalds kfree(ahp); 5431da177e4SLinus Torvalds } 5441da177e4SLinus Torvalds 545e5b56454SSteffen Klassert static int ah4_rcv_cb(struct sk_buff *skb, int err) 546e5b56454SSteffen Klassert { 547e5b56454SSteffen Klassert return 0; 548e5b56454SSteffen Klassert } 5491da177e4SLinus Torvalds 550533cb5b0SEric Dumazet static const struct xfrm_type ah_type = 5511da177e4SLinus Torvalds { 5521da177e4SLinus Torvalds .description = "AH4", 5531da177e4SLinus Torvalds .owner = THIS_MODULE, 5541da177e4SLinus Torvalds .proto = IPPROTO_AH, 555436a0a40SHerbert Xu .flags = XFRM_TYPE_REPLAY_PROT, 5561da177e4SLinus Torvalds .init_state = ah_init_state, 5571da177e4SLinus Torvalds .destructor = ah_destroy, 5581da177e4SLinus Torvalds .input = ah_input, 5591da177e4SLinus Torvalds .output = ah_output 5601da177e4SLinus Torvalds }; 5611da177e4SLinus Torvalds 562e5b56454SSteffen Klassert static struct xfrm4_protocol ah4_protocol = { 5631da177e4SLinus Torvalds .handler = xfrm4_rcv, 564e5b56454SSteffen Klassert .input_handler = xfrm_input, 565e5b56454SSteffen Klassert .cb_handler = ah4_rcv_cb, 5661da177e4SLinus Torvalds .err_handler = ah4_err, 567e5b56454SSteffen Klassert .priority = 0, 5681da177e4SLinus Torvalds }; 5691da177e4SLinus Torvalds 5701da177e4SLinus Torvalds static int __init ah4_init(void) 5711da177e4SLinus Torvalds { 5721da177e4SLinus Torvalds if (xfrm_register_type(&ah_type, AF_INET) < 0) { 573058bd4d2SJoe Perches pr_info("%s: can't add xfrm type\n", __func__); 5741da177e4SLinus Torvalds return -EAGAIN; 5751da177e4SLinus Torvalds } 576e5b56454SSteffen Klassert if (xfrm4_protocol_register(&ah4_protocol, IPPROTO_AH) < 0) { 577058bd4d2SJoe Perches pr_info("%s: can't add protocol\n", __func__); 5781da177e4SLinus Torvalds xfrm_unregister_type(&ah_type, AF_INET); 5791da177e4SLinus Torvalds return -EAGAIN; 5801da177e4SLinus Torvalds } 5811da177e4SLinus Torvalds return 0; 5821da177e4SLinus Torvalds } 5831da177e4SLinus Torvalds 5841da177e4SLinus Torvalds static void __exit ah4_fini(void) 5851da177e4SLinus Torvalds { 586e5b56454SSteffen Klassert if (xfrm4_protocol_deregister(&ah4_protocol, IPPROTO_AH) < 0) 587058bd4d2SJoe Perches pr_info("%s: can't remove protocol\n", __func__); 5881da177e4SLinus Torvalds if (xfrm_unregister_type(&ah_type, AF_INET) < 0) 589058bd4d2SJoe Perches pr_info("%s: can't remove xfrm type\n", __func__); 5901da177e4SLinus Torvalds } 5911da177e4SLinus Torvalds 5921da177e4SLinus Torvalds module_init(ah4_init); 5931da177e4SLinus Torvalds module_exit(ah4_fini); 5941da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 595d3d6dd3aSMasahide NAKAMURA MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_AH); 596