1dff3bb06SSteffen Klassert #include <crypto/hash.h> 207d4ee58SHerbert Xu #include <linux/err.h> 31da177e4SLinus Torvalds #include <linux/module.h> 45a0e3ad6STejun Heo #include <linux/slab.h> 51da177e4SLinus Torvalds #include <net/ip.h> 61da177e4SLinus Torvalds #include <net/xfrm.h> 71da177e4SLinus Torvalds #include <net/ah.h> 81da177e4SLinus Torvalds #include <linux/crypto.h> 91da177e4SLinus Torvalds #include <linux/pfkeyv2.h> 10dff3bb06SSteffen Klassert #include <linux/scatterlist.h> 111da177e4SLinus Torvalds #include <net/icmp.h> 1214c85021SArnaldo Carvalho de Melo #include <net/protocol.h> 131da177e4SLinus Torvalds 14dff3bb06SSteffen Klassert struct ah_skb_cb { 15dff3bb06SSteffen Klassert struct xfrm_skb_cb xfrm; 16dff3bb06SSteffen Klassert void *tmp; 17dff3bb06SSteffen Klassert }; 18dff3bb06SSteffen Klassert 19dff3bb06SSteffen Klassert #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) 20dff3bb06SSteffen Klassert 21dff3bb06SSteffen Klassert static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, 22dff3bb06SSteffen Klassert unsigned int size) 23dff3bb06SSteffen Klassert { 24dff3bb06SSteffen Klassert unsigned int len; 25dff3bb06SSteffen Klassert 26dff3bb06SSteffen Klassert len = size + crypto_ahash_digestsize(ahash) + 27dff3bb06SSteffen Klassert (crypto_ahash_alignmask(ahash) & 28dff3bb06SSteffen Klassert ~(crypto_tfm_ctx_alignment() - 1)); 29dff3bb06SSteffen Klassert 30dff3bb06SSteffen Klassert len = ALIGN(len, crypto_tfm_ctx_alignment()); 31dff3bb06SSteffen Klassert 32dff3bb06SSteffen Klassert len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); 33dff3bb06SSteffen Klassert len = ALIGN(len, __alignof__(struct scatterlist)); 34dff3bb06SSteffen Klassert 35dff3bb06SSteffen Klassert len += sizeof(struct scatterlist) * nfrags; 36dff3bb06SSteffen Klassert 37dff3bb06SSteffen Klassert return kmalloc(len, GFP_ATOMIC); 38dff3bb06SSteffen Klassert } 39dff3bb06SSteffen Klassert 40dff3bb06SSteffen Klassert static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset) 41dff3bb06SSteffen Klassert { 42dff3bb06SSteffen Klassert return tmp + offset; 43dff3bb06SSteffen Klassert } 44dff3bb06SSteffen Klassert 45dff3bb06SSteffen Klassert static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, 46dff3bb06SSteffen Klassert unsigned int offset) 47dff3bb06SSteffen Klassert { 48dff3bb06SSteffen Klassert return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); 49dff3bb06SSteffen Klassert } 50dff3bb06SSteffen Klassert 51dff3bb06SSteffen Klassert static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, 52dff3bb06SSteffen Klassert u8 *icv) 53dff3bb06SSteffen Klassert { 54dff3bb06SSteffen Klassert struct ahash_request *req; 55dff3bb06SSteffen Klassert 56dff3bb06SSteffen Klassert req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), 57dff3bb06SSteffen Klassert crypto_tfm_ctx_alignment()); 58dff3bb06SSteffen Klassert 59dff3bb06SSteffen Klassert ahash_request_set_tfm(req, ahash); 60dff3bb06SSteffen Klassert 61dff3bb06SSteffen Klassert return req; 62dff3bb06SSteffen Klassert } 63dff3bb06SSteffen Klassert 64dff3bb06SSteffen Klassert static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, 65dff3bb06SSteffen Klassert struct ahash_request *req) 66dff3bb06SSteffen Klassert { 67dff3bb06SSteffen Klassert return (void *)ALIGN((unsigned long)(req + 1) + 68dff3bb06SSteffen Klassert crypto_ahash_reqsize(ahash), 69dff3bb06SSteffen Klassert __alignof__(struct scatterlist)); 70dff3bb06SSteffen Klassert } 711da177e4SLinus Torvalds 721da177e4SLinus Torvalds /* Clear mutable options and find final destination to substitute 731da177e4SLinus Torvalds * into IP header for icv calculation. Options are already checked 741da177e4SLinus Torvalds * for validity, so paranoia is not required. */ 751da177e4SLinus Torvalds 76b71d1d42SEric Dumazet static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr) 771da177e4SLinus Torvalds { 781da177e4SLinus Torvalds unsigned char * optptr = (unsigned char*)(iph+1); 791da177e4SLinus Torvalds int l = iph->ihl*4 - sizeof(struct iphdr); 801da177e4SLinus Torvalds int optlen; 811da177e4SLinus Torvalds 821da177e4SLinus Torvalds while (l > 0) { 831da177e4SLinus Torvalds switch (*optptr) { 841da177e4SLinus Torvalds case IPOPT_END: 851da177e4SLinus Torvalds return 0; 861da177e4SLinus Torvalds case IPOPT_NOOP: 871da177e4SLinus Torvalds l--; 881da177e4SLinus Torvalds optptr++; 891da177e4SLinus Torvalds continue; 901da177e4SLinus Torvalds } 911da177e4SLinus Torvalds optlen = optptr[1]; 921da177e4SLinus Torvalds if (optlen<2 || optlen>l) 931da177e4SLinus Torvalds return -EINVAL; 941da177e4SLinus Torvalds switch (*optptr) { 951da177e4SLinus Torvalds case IPOPT_SEC: 961da177e4SLinus Torvalds case 0x85: /* Some "Extended Security" crap. */ 9711a03f78SPaul Moore case IPOPT_CIPSO: 981da177e4SLinus Torvalds case IPOPT_RA: 991da177e4SLinus Torvalds case 0x80|21: /* RFC1770 */ 1001da177e4SLinus Torvalds break; 1011da177e4SLinus Torvalds case IPOPT_LSRR: 1021da177e4SLinus Torvalds case IPOPT_SSRR: 1031da177e4SLinus Torvalds if (optlen < 6) 1041da177e4SLinus Torvalds return -EINVAL; 1051da177e4SLinus Torvalds memcpy(daddr, optptr+optlen-4, 4); 1061da177e4SLinus Torvalds /* Fall through */ 1071da177e4SLinus Torvalds default: 10896fe1c02SNick Bowler memset(optptr, 0, optlen); 1091da177e4SLinus Torvalds } 1101da177e4SLinus Torvalds l -= optlen; 1111da177e4SLinus Torvalds optptr += optlen; 1121da177e4SLinus Torvalds } 1131da177e4SLinus Torvalds return 0; 1141da177e4SLinus Torvalds } 1151da177e4SLinus Torvalds 116dff3bb06SSteffen Klassert static void ah_output_done(struct crypto_async_request *base, int err) 117dff3bb06SSteffen Klassert { 118dff3bb06SSteffen Klassert u8 *icv; 119dff3bb06SSteffen Klassert struct iphdr *iph; 120dff3bb06SSteffen Klassert struct sk_buff *skb = base->data; 121dff3bb06SSteffen Klassert struct xfrm_state *x = skb_dst(skb)->xfrm; 122dff3bb06SSteffen Klassert struct ah_data *ahp = x->data; 123dff3bb06SSteffen Klassert struct iphdr *top_iph = ip_hdr(skb); 124dff3bb06SSteffen Klassert struct ip_auth_hdr *ah = ip_auth_hdr(skb); 125dff3bb06SSteffen Klassert int ihl = ip_hdrlen(skb); 126dff3bb06SSteffen Klassert 127dff3bb06SSteffen Klassert iph = AH_SKB_CB(skb)->tmp; 128dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahp->ahash, iph, ihl); 129dff3bb06SSteffen Klassert memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 130dff3bb06SSteffen Klassert 131dff3bb06SSteffen Klassert top_iph->tos = iph->tos; 132dff3bb06SSteffen Klassert top_iph->ttl = iph->ttl; 133dff3bb06SSteffen Klassert top_iph->frag_off = iph->frag_off; 134dff3bb06SSteffen Klassert if (top_iph->ihl != 5) { 135dff3bb06SSteffen Klassert top_iph->daddr = iph->daddr; 136dff3bb06SSteffen Klassert memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); 137dff3bb06SSteffen Klassert } 138dff3bb06SSteffen Klassert 139dff3bb06SSteffen Klassert err = ah->nexthdr; 140dff3bb06SSteffen Klassert 141dff3bb06SSteffen Klassert kfree(AH_SKB_CB(skb)->tmp); 142dff3bb06SSteffen Klassert xfrm_output_resume(skb, err); 143dff3bb06SSteffen Klassert } 144dff3bb06SSteffen Klassert 1451da177e4SLinus Torvalds static int ah_output(struct xfrm_state *x, struct sk_buff *skb) 1461da177e4SLinus Torvalds { 1471da177e4SLinus Torvalds int err; 148dff3bb06SSteffen Klassert int nfrags; 149dff3bb06SSteffen Klassert int ihl; 150dff3bb06SSteffen Klassert u8 *icv; 151dff3bb06SSteffen Klassert struct sk_buff *trailer; 152dff3bb06SSteffen Klassert struct crypto_ahash *ahash; 153dff3bb06SSteffen Klassert struct ahash_request *req; 154dff3bb06SSteffen Klassert struct scatterlist *sg; 1551da177e4SLinus Torvalds struct iphdr *iph, *top_iph; 1561da177e4SLinus Torvalds struct ip_auth_hdr *ah; 1571da177e4SLinus Torvalds struct ah_data *ahp; 158dff3bb06SSteffen Klassert 159dff3bb06SSteffen Klassert ahp = x->data; 160dff3bb06SSteffen Klassert ahash = ahp->ahash; 161dff3bb06SSteffen Klassert 162dff3bb06SSteffen Klassert if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 163dff3bb06SSteffen Klassert goto out; 164dff3bb06SSteffen Klassert nfrags = err; 1651da177e4SLinus Torvalds 1667b277b1aSHerbert Xu skb_push(skb, -skb_network_offset(skb)); 167dff3bb06SSteffen Klassert ah = ip_auth_hdr(skb); 168dff3bb06SSteffen Klassert ihl = ip_hdrlen(skb); 169dff3bb06SSteffen Klassert 170dff3bb06SSteffen Klassert err = -ENOMEM; 171dff3bb06SSteffen Klassert iph = ah_alloc_tmp(ahash, nfrags, ihl); 172dff3bb06SSteffen Klassert if (!iph) 173dff3bb06SSteffen Klassert goto out; 174dff3bb06SSteffen Klassert 175dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahash, iph, ihl); 176dff3bb06SSteffen Klassert req = ah_tmp_req(ahash, icv); 177dff3bb06SSteffen Klassert sg = ah_req_sg(ahash, req); 178dff3bb06SSteffen Klassert 179dff3bb06SSteffen Klassert memset(ah->auth_data, 0, ahp->icv_trunc_len); 180dff3bb06SSteffen Klassert 181eddc9ec5SArnaldo Carvalho de Melo top_iph = ip_hdr(skb); 1821da177e4SLinus Torvalds 1831da177e4SLinus Torvalds iph->tos = top_iph->tos; 1841da177e4SLinus Torvalds iph->ttl = top_iph->ttl; 1851da177e4SLinus Torvalds iph->frag_off = top_iph->frag_off; 1861da177e4SLinus Torvalds 1871da177e4SLinus Torvalds if (top_iph->ihl != 5) { 1881da177e4SLinus Torvalds iph->daddr = top_iph->daddr; 1891da177e4SLinus Torvalds memcpy(iph+1, top_iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); 1901da177e4SLinus Torvalds err = ip_clear_mutable_options(top_iph, &top_iph->daddr); 1911da177e4SLinus Torvalds if (err) 192dff3bb06SSteffen Klassert goto out_free; 1931da177e4SLinus Torvalds } 1941da177e4SLinus Torvalds 19537fedd3aSHerbert Xu ah->nexthdr = *skb_mac_header(skb); 19637fedd3aSHerbert Xu *skb_mac_header(skb) = IPPROTO_AH; 1971da177e4SLinus Torvalds 1981da177e4SLinus Torvalds top_iph->tos = 0; 1991da177e4SLinus Torvalds top_iph->tot_len = htons(skb->len); 2001da177e4SLinus Torvalds top_iph->frag_off = 0; 2011da177e4SLinus Torvalds top_iph->ttl = 0; 2021da177e4SLinus Torvalds top_iph->check = 0; 2031da177e4SLinus Torvalds 204fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4) 205fa9921e4SNicolas Dichtel ah->hdrlen = (XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; 206fa9921e4SNicolas Dichtel else 20787bdc48dSHerbert Xu ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; 2081da177e4SLinus Torvalds 2091da177e4SLinus Torvalds ah->reserved = 0; 2101da177e4SLinus Torvalds ah->spi = x->id.spi; 2111ce3644aSSteffen Klassert ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 212b7c6538cSHerbert Xu 213dff3bb06SSteffen Klassert sg_init_table(sg, nfrags); 214dff3bb06SSteffen Klassert skb_to_sgvec(skb, sg, 0, skb->len); 215b7c6538cSHerbert Xu 216dff3bb06SSteffen Klassert ahash_request_set_crypt(req, sg, icv, skb->len); 217dff3bb06SSteffen Klassert ahash_request_set_callback(req, 0, ah_output_done, skb); 218dff3bb06SSteffen Klassert 219dff3bb06SSteffen Klassert AH_SKB_CB(skb)->tmp = iph; 220dff3bb06SSteffen Klassert 221dff3bb06SSteffen Klassert err = crypto_ahash_digest(req); 222dff3bb06SSteffen Klassert if (err) { 223dff3bb06SSteffen Klassert if (err == -EINPROGRESS) 224dff3bb06SSteffen Klassert goto out; 225dff3bb06SSteffen Klassert 226dff3bb06SSteffen Klassert if (err == -EBUSY) 227dff3bb06SSteffen Klassert err = NET_XMIT_DROP; 228dff3bb06SSteffen Klassert goto out_free; 229dff3bb06SSteffen Klassert } 230dff3bb06SSteffen Klassert 231dff3bb06SSteffen Klassert memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 2321da177e4SLinus Torvalds 2331da177e4SLinus Torvalds top_iph->tos = iph->tos; 2341da177e4SLinus Torvalds top_iph->ttl = iph->ttl; 2351da177e4SLinus Torvalds top_iph->frag_off = iph->frag_off; 2361da177e4SLinus Torvalds if (top_iph->ihl != 5) { 2371da177e4SLinus Torvalds top_iph->daddr = iph->daddr; 2381da177e4SLinus Torvalds memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); 2391da177e4SLinus Torvalds } 2401da177e4SLinus Torvalds 241dff3bb06SSteffen Klassert out_free: 242dff3bb06SSteffen Klassert kfree(iph); 243dff3bb06SSteffen Klassert out: 2441da177e4SLinus Torvalds return err; 2451da177e4SLinus Torvalds } 2461da177e4SLinus Torvalds 247dff3bb06SSteffen Klassert static void ah_input_done(struct crypto_async_request *base, int err) 248dff3bb06SSteffen Klassert { 249dff3bb06SSteffen Klassert u8 *auth_data; 250dff3bb06SSteffen Klassert u8 *icv; 251dff3bb06SSteffen Klassert struct iphdr *work_iph; 252dff3bb06SSteffen Klassert struct sk_buff *skb = base->data; 253dff3bb06SSteffen Klassert struct xfrm_state *x = xfrm_input_state(skb); 254dff3bb06SSteffen Klassert struct ah_data *ahp = x->data; 255dff3bb06SSteffen Klassert struct ip_auth_hdr *ah = ip_auth_hdr(skb); 256dff3bb06SSteffen Klassert int ihl = ip_hdrlen(skb); 257dff3bb06SSteffen Klassert int ah_hlen = (ah->hdrlen + 2) << 2; 258dff3bb06SSteffen Klassert 259dff3bb06SSteffen Klassert work_iph = AH_SKB_CB(skb)->tmp; 260dff3bb06SSteffen Klassert auth_data = ah_tmp_auth(work_iph, ihl); 261dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len); 262dff3bb06SSteffen Klassert 263dff3bb06SSteffen Klassert err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 264dff3bb06SSteffen Klassert if (err) 265dff3bb06SSteffen Klassert goto out; 266dff3bb06SSteffen Klassert 267dff3bb06SSteffen Klassert skb->network_header += ah_hlen; 268dff3bb06SSteffen Klassert memcpy(skb_network_header(skb), work_iph, ihl); 269dff3bb06SSteffen Klassert __skb_pull(skb, ah_hlen + ihl); 270dff3bb06SSteffen Klassert skb_set_transport_header(skb, -ihl); 271dff3bb06SSteffen Klassert 272dff3bb06SSteffen Klassert err = ah->nexthdr; 273dff3bb06SSteffen Klassert out: 274dff3bb06SSteffen Klassert kfree(AH_SKB_CB(skb)->tmp); 275dff3bb06SSteffen Klassert xfrm_input_resume(skb, err); 276dff3bb06SSteffen Klassert } 277dff3bb06SSteffen Klassert 278e695633eSHerbert Xu static int ah_input(struct xfrm_state *x, struct sk_buff *skb) 2791da177e4SLinus Torvalds { 2801da177e4SLinus Torvalds int ah_hlen; 28131a4ab93SHerbert Xu int ihl; 282631a6698SHerbert Xu int nexthdr; 283dff3bb06SSteffen Klassert int nfrags; 284dff3bb06SSteffen Klassert u8 *auth_data; 285dff3bb06SSteffen Klassert u8 *icv; 286dff3bb06SSteffen Klassert struct sk_buff *trailer; 287dff3bb06SSteffen Klassert struct crypto_ahash *ahash; 288dff3bb06SSteffen Klassert struct ahash_request *req; 289dff3bb06SSteffen Klassert struct scatterlist *sg; 290dff3bb06SSteffen Klassert struct iphdr *iph, *work_iph; 2911da177e4SLinus Torvalds struct ip_auth_hdr *ah; 2921da177e4SLinus Torvalds struct ah_data *ahp; 293dff3bb06SSteffen Klassert int err = -ENOMEM; 2941da177e4SLinus Torvalds 29587bdc48dSHerbert Xu if (!pskb_may_pull(skb, sizeof(*ah))) 2961da177e4SLinus Torvalds goto out; 2971da177e4SLinus Torvalds 2981da177e4SLinus Torvalds ah = (struct ip_auth_hdr *)skb->data; 2991da177e4SLinus Torvalds ahp = x->data; 300dff3bb06SSteffen Klassert ahash = ahp->ahash; 301dff3bb06SSteffen Klassert 302631a6698SHerbert Xu nexthdr = ah->nexthdr; 3031da177e4SLinus Torvalds ah_hlen = (ah->hdrlen + 2) << 2; 3041da177e4SLinus Torvalds 305fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4) { 306fa9921e4SNicolas Dichtel if (ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_full_len) && 307fa9921e4SNicolas Dichtel ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len)) 308fa9921e4SNicolas Dichtel goto out; 309fa9921e4SNicolas Dichtel } else { 31087bdc48dSHerbert Xu if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && 31187bdc48dSHerbert Xu ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) 3121da177e4SLinus Torvalds goto out; 313fa9921e4SNicolas Dichtel } 3141da177e4SLinus Torvalds 3151da177e4SLinus Torvalds if (!pskb_may_pull(skb, ah_hlen)) 3161da177e4SLinus Torvalds goto out; 3171da177e4SLinus Torvalds 3181da177e4SLinus Torvalds /* We are going to _remove_ AH header to keep sockets happy, 3191da177e4SLinus Torvalds * so... Later this can change. */ 3201da177e4SLinus Torvalds if (skb_cloned(skb) && 3211da177e4SLinus Torvalds pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) 3221da177e4SLinus Torvalds goto out; 3231da177e4SLinus Torvalds 3241da177e4SLinus Torvalds skb->ip_summed = CHECKSUM_NONE; 3251da177e4SLinus Torvalds 3261da177e4SLinus Torvalds 327dff3bb06SSteffen Klassert if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 328dff3bb06SSteffen Klassert goto out; 329dff3bb06SSteffen Klassert nfrags = err; 330dff3bb06SSteffen Klassert 3314b0ef1f2SDang Hongwu ah = (struct ip_auth_hdr *)skb->data; 3324b0ef1f2SDang Hongwu iph = ip_hdr(skb); 3334b0ef1f2SDang Hongwu ihl = ip_hdrlen(skb); 3344b0ef1f2SDang Hongwu 335dff3bb06SSteffen Klassert work_iph = ah_alloc_tmp(ahash, nfrags, ihl + ahp->icv_trunc_len); 336dff3bb06SSteffen Klassert if (!work_iph) 337dff3bb06SSteffen Klassert goto out; 338dff3bb06SSteffen Klassert 339dff3bb06SSteffen Klassert auth_data = ah_tmp_auth(work_iph, ihl); 340dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len); 341dff3bb06SSteffen Klassert req = ah_tmp_req(ahash, icv); 342dff3bb06SSteffen Klassert sg = ah_req_sg(ahash, req); 343dff3bb06SSteffen Klassert 344dff3bb06SSteffen Klassert memcpy(work_iph, iph, ihl); 345dff3bb06SSteffen Klassert memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); 346dff3bb06SSteffen Klassert memset(ah->auth_data, 0, ahp->icv_trunc_len); 3471da177e4SLinus Torvalds 3481da177e4SLinus Torvalds iph->ttl = 0; 3491da177e4SLinus Torvalds iph->tos = 0; 3501da177e4SLinus Torvalds iph->frag_off = 0; 3511da177e4SLinus Torvalds iph->check = 0; 35231a4ab93SHerbert Xu if (ihl > sizeof(*iph)) { 353d5a0a1e3SAl Viro __be32 dummy; 354dff3bb06SSteffen Klassert err = ip_clear_mutable_options(iph, &dummy); 355dff3bb06SSteffen Klassert if (err) 356dff3bb06SSteffen Klassert goto out_free; 3571da177e4SLinus Torvalds } 3580ebea8efSHerbert Xu 35931a4ab93SHerbert Xu skb_push(skb, ihl); 3600ebea8efSHerbert Xu 361dff3bb06SSteffen Klassert sg_init_table(sg, nfrags); 362dff3bb06SSteffen Klassert skb_to_sgvec(skb, sg, 0, skb->len); 363dff3bb06SSteffen Klassert 364dff3bb06SSteffen Klassert ahash_request_set_crypt(req, sg, icv, skb->len); 365dff3bb06SSteffen Klassert ahash_request_set_callback(req, 0, ah_input_done, skb); 366dff3bb06SSteffen Klassert 367dff3bb06SSteffen Klassert AH_SKB_CB(skb)->tmp = work_iph; 368dff3bb06SSteffen Klassert 369dff3bb06SSteffen Klassert err = crypto_ahash_digest(req); 370dff3bb06SSteffen Klassert if (err) { 371dff3bb06SSteffen Klassert if (err == -EINPROGRESS) 3721da177e4SLinus Torvalds goto out; 3730ebea8efSHerbert Xu 374dff3bb06SSteffen Klassert if (err == -EBUSY) 375dff3bb06SSteffen Klassert err = NET_XMIT_DROP; 376dff3bb06SSteffen Klassert goto out_free; 377dff3bb06SSteffen Klassert } 378dff3bb06SSteffen Klassert 379dff3bb06SSteffen Klassert err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 380dff3bb06SSteffen Klassert if (err) 381dff3bb06SSteffen Klassert goto out_free; 382dff3bb06SSteffen Klassert 383b0e380b1SArnaldo Carvalho de Melo skb->network_header += ah_hlen; 384dff3bb06SSteffen Klassert memcpy(skb_network_header(skb), work_iph, ihl); 38531a4ab93SHerbert Xu __skb_pull(skb, ah_hlen + ihl); 386dff3bb06SSteffen Klassert skb_set_transport_header(skb, -ihl); 3871da177e4SLinus Torvalds 388dff3bb06SSteffen Klassert err = nexthdr; 3891da177e4SLinus Torvalds 390dff3bb06SSteffen Klassert out_free: 391dff3bb06SSteffen Klassert kfree (work_iph); 3921da177e4SLinus Torvalds out: 39307d4ee58SHerbert Xu return err; 3941da177e4SLinus Torvalds } 3951da177e4SLinus Torvalds 3961da177e4SLinus Torvalds static void ah4_err(struct sk_buff *skb, u32 info) 3971da177e4SLinus Torvalds { 3984fb236baSAlexey Dobriyan struct net *net = dev_net(skb->dev); 399b71d1d42SEric Dumazet const struct iphdr *iph = (const struct iphdr *)skb->data; 4001da177e4SLinus Torvalds struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); 4011da177e4SLinus Torvalds struct xfrm_state *x; 4021da177e4SLinus Torvalds 40388c7664fSArnaldo Carvalho de Melo if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH || 40488c7664fSArnaldo Carvalho de Melo icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) 4051da177e4SLinus Torvalds return; 4061da177e4SLinus Torvalds 407b71d1d42SEric Dumazet x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 408b71d1d42SEric Dumazet ah->spi, IPPROTO_AH, AF_INET); 4091da177e4SLinus Torvalds if (!x) 4101da177e4SLinus Torvalds return; 4111da177e4SLinus Torvalds printk(KERN_DEBUG "pmtu discovery on SA AH/%08x/%08x\n", 4121da177e4SLinus Torvalds ntohl(ah->spi), ntohl(iph->daddr)); 4131da177e4SLinus Torvalds xfrm_state_put(x); 4141da177e4SLinus Torvalds } 4151da177e4SLinus Torvalds 41672cb6962SHerbert Xu static int ah_init_state(struct xfrm_state *x) 4171da177e4SLinus Torvalds { 4181da177e4SLinus Torvalds struct ah_data *ahp = NULL; 4191da177e4SLinus Torvalds struct xfrm_algo_desc *aalg_desc; 420dff3bb06SSteffen Klassert struct crypto_ahash *ahash; 4211da177e4SLinus Torvalds 4221da177e4SLinus Torvalds if (!x->aalg) 4231da177e4SLinus Torvalds goto error; 4241da177e4SLinus Torvalds 4251da177e4SLinus Torvalds if (x->encap) 4261da177e4SLinus Torvalds goto error; 4271da177e4SLinus Torvalds 4280da974f4SPanagiotis Issaris ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); 429dff3bb06SSteffen Klassert if (!ahp) 4301da177e4SLinus Torvalds return -ENOMEM; 4311da177e4SLinus Torvalds 432dff3bb06SSteffen Klassert ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); 433dff3bb06SSteffen Klassert if (IS_ERR(ahash)) 4341da177e4SLinus Torvalds goto error; 43507d4ee58SHerbert Xu 436dff3bb06SSteffen Klassert ahp->ahash = ahash; 437dff3bb06SSteffen Klassert if (crypto_ahash_setkey(ahash, x->aalg->alg_key, 438bc31d3b2SHerbert Xu (x->aalg->alg_key_len + 7) / 8)) 43907d4ee58SHerbert Xu goto error; 4401da177e4SLinus Torvalds 4411da177e4SLinus Torvalds /* 4421da177e4SLinus Torvalds * Lookup the algorithm description maintained by xfrm_algo, 4431da177e4SLinus Torvalds * verify crypto transform properties, and store information 4441da177e4SLinus Torvalds * we need for AH processing. This lookup cannot fail here 445dff3bb06SSteffen Klassert * after a successful crypto_alloc_ahash(). 4461da177e4SLinus Torvalds */ 4471da177e4SLinus Torvalds aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 4481da177e4SLinus Torvalds BUG_ON(!aalg_desc); 4491da177e4SLinus Torvalds 4501da177e4SLinus Torvalds if (aalg_desc->uinfo.auth.icv_fullbits/8 != 451dff3bb06SSteffen Klassert crypto_ahash_digestsize(ahash)) { 4521da177e4SLinus Torvalds printk(KERN_INFO "AH: %s digestsize %u != %hu\n", 453dff3bb06SSteffen Klassert x->aalg->alg_name, crypto_ahash_digestsize(ahash), 4541da177e4SLinus Torvalds aalg_desc->uinfo.auth.icv_fullbits/8); 4551da177e4SLinus Torvalds goto error; 4561da177e4SLinus Torvalds } 4571da177e4SLinus Torvalds 4581da177e4SLinus Torvalds ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; 4598f8a088cSMartin Willi ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; 4601da177e4SLinus Torvalds 4611da177e4SLinus Torvalds BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN); 4621da177e4SLinus Torvalds 463fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4) 464fa9921e4SNicolas Dichtel x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) + 465fa9921e4SNicolas Dichtel ahp->icv_trunc_len); 466fa9921e4SNicolas Dichtel else 46787bdc48dSHerbert Xu x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + 46887bdc48dSHerbert Xu ahp->icv_trunc_len); 4697e49e6deSMasahide NAKAMURA if (x->props.mode == XFRM_MODE_TUNNEL) 4701da177e4SLinus Torvalds x->props.header_len += sizeof(struct iphdr); 4711da177e4SLinus Torvalds x->data = ahp; 4721da177e4SLinus Torvalds 4731da177e4SLinus Torvalds return 0; 4741da177e4SLinus Torvalds 4751da177e4SLinus Torvalds error: 4761da177e4SLinus Torvalds if (ahp) { 477dff3bb06SSteffen Klassert crypto_free_ahash(ahp->ahash); 4781da177e4SLinus Torvalds kfree(ahp); 4791da177e4SLinus Torvalds } 4801da177e4SLinus Torvalds return -EINVAL; 4811da177e4SLinus Torvalds } 4821da177e4SLinus Torvalds 4831da177e4SLinus Torvalds static void ah_destroy(struct xfrm_state *x) 4841da177e4SLinus Torvalds { 4851da177e4SLinus Torvalds struct ah_data *ahp = x->data; 4861da177e4SLinus Torvalds 4871da177e4SLinus Torvalds if (!ahp) 4881da177e4SLinus Torvalds return; 4891da177e4SLinus Torvalds 490dff3bb06SSteffen Klassert crypto_free_ahash(ahp->ahash); 4911da177e4SLinus Torvalds kfree(ahp); 4921da177e4SLinus Torvalds } 4931da177e4SLinus Torvalds 4941da177e4SLinus Torvalds 495533cb5b0SEric Dumazet static const struct xfrm_type ah_type = 4961da177e4SLinus Torvalds { 4971da177e4SLinus Torvalds .description = "AH4", 4981da177e4SLinus Torvalds .owner = THIS_MODULE, 4991da177e4SLinus Torvalds .proto = IPPROTO_AH, 500436a0a40SHerbert Xu .flags = XFRM_TYPE_REPLAY_PROT, 5011da177e4SLinus Torvalds .init_state = ah_init_state, 5021da177e4SLinus Torvalds .destructor = ah_destroy, 5031da177e4SLinus Torvalds .input = ah_input, 5041da177e4SLinus Torvalds .output = ah_output 5051da177e4SLinus Torvalds }; 5061da177e4SLinus Torvalds 50732613090SAlexey Dobriyan static const struct net_protocol ah4_protocol = { 5081da177e4SLinus Torvalds .handler = xfrm4_rcv, 5091da177e4SLinus Torvalds .err_handler = ah4_err, 5101da177e4SLinus Torvalds .no_policy = 1, 5114fb236baSAlexey Dobriyan .netns_ok = 1, 5121da177e4SLinus Torvalds }; 5131da177e4SLinus Torvalds 5141da177e4SLinus Torvalds static int __init ah4_init(void) 5151da177e4SLinus Torvalds { 5161da177e4SLinus Torvalds if (xfrm_register_type(&ah_type, AF_INET) < 0) { 5171da177e4SLinus Torvalds printk(KERN_INFO "ip ah init: can't add xfrm type\n"); 5181da177e4SLinus Torvalds return -EAGAIN; 5191da177e4SLinus Torvalds } 5201da177e4SLinus Torvalds if (inet_add_protocol(&ah4_protocol, IPPROTO_AH) < 0) { 5211da177e4SLinus Torvalds printk(KERN_INFO "ip ah init: can't add protocol\n"); 5221da177e4SLinus Torvalds xfrm_unregister_type(&ah_type, AF_INET); 5231da177e4SLinus Torvalds return -EAGAIN; 5241da177e4SLinus Torvalds } 5251da177e4SLinus Torvalds return 0; 5261da177e4SLinus Torvalds } 5271da177e4SLinus Torvalds 5281da177e4SLinus Torvalds static void __exit ah4_fini(void) 5291da177e4SLinus Torvalds { 5301da177e4SLinus Torvalds if (inet_del_protocol(&ah4_protocol, IPPROTO_AH) < 0) 5311da177e4SLinus Torvalds printk(KERN_INFO "ip ah close: can't remove protocol\n"); 5321da177e4SLinus Torvalds if (xfrm_unregister_type(&ah_type, AF_INET) < 0) 5331da177e4SLinus Torvalds printk(KERN_INFO "ip ah close: can't remove xfrm type\n"); 5341da177e4SLinus Torvalds } 5351da177e4SLinus Torvalds 5361da177e4SLinus Torvalds module_init(ah4_init); 5371da177e4SLinus Torvalds module_exit(ah4_fini); 5381da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 539d3d6dd3aSMasahide NAKAMURA MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_AH); 540