1afd46503SJoe Perches #define pr_fmt(fmt) "IPsec: " fmt 2afd46503SJoe Perches 3dff3bb06SSteffen Klassert #include <crypto/hash.h> 407d4ee58SHerbert Xu #include <linux/err.h> 51da177e4SLinus Torvalds #include <linux/module.h> 65a0e3ad6STejun Heo #include <linux/slab.h> 71da177e4SLinus Torvalds #include <net/ip.h> 81da177e4SLinus Torvalds #include <net/xfrm.h> 91da177e4SLinus Torvalds #include <net/ah.h> 101da177e4SLinus Torvalds #include <linux/crypto.h> 111da177e4SLinus Torvalds #include <linux/pfkeyv2.h> 12dff3bb06SSteffen Klassert #include <linux/scatterlist.h> 131da177e4SLinus Torvalds #include <net/icmp.h> 1414c85021SArnaldo Carvalho de Melo #include <net/protocol.h> 151da177e4SLinus Torvalds 16dff3bb06SSteffen Klassert struct ah_skb_cb { 17dff3bb06SSteffen Klassert struct xfrm_skb_cb xfrm; 18dff3bb06SSteffen Klassert void *tmp; 19dff3bb06SSteffen Klassert }; 20dff3bb06SSteffen Klassert 21dff3bb06SSteffen Klassert #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) 22dff3bb06SSteffen Klassert 23dff3bb06SSteffen Klassert static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, 24dff3bb06SSteffen Klassert unsigned int size) 25dff3bb06SSteffen Klassert { 26dff3bb06SSteffen Klassert unsigned int len; 27dff3bb06SSteffen Klassert 28dff3bb06SSteffen Klassert len = size + crypto_ahash_digestsize(ahash) + 29dff3bb06SSteffen Klassert (crypto_ahash_alignmask(ahash) & 30dff3bb06SSteffen Klassert ~(crypto_tfm_ctx_alignment() - 1)); 31dff3bb06SSteffen Klassert 32dff3bb06SSteffen Klassert len = ALIGN(len, crypto_tfm_ctx_alignment()); 33dff3bb06SSteffen Klassert 34dff3bb06SSteffen Klassert len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); 35dff3bb06SSteffen Klassert len = ALIGN(len, __alignof__(struct scatterlist)); 36dff3bb06SSteffen Klassert 37dff3bb06SSteffen Klassert len += sizeof(struct scatterlist) * nfrags; 38dff3bb06SSteffen Klassert 39dff3bb06SSteffen Klassert return kmalloc(len, GFP_ATOMIC); 40dff3bb06SSteffen Klassert } 41dff3bb06SSteffen Klassert 42dff3bb06SSteffen Klassert static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset) 43dff3bb06SSteffen Klassert { 44dff3bb06SSteffen Klassert return tmp + offset; 45dff3bb06SSteffen Klassert } 46dff3bb06SSteffen Klassert 47dff3bb06SSteffen Klassert static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, 48dff3bb06SSteffen Klassert unsigned int offset) 49dff3bb06SSteffen Klassert { 50dff3bb06SSteffen Klassert return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); 51dff3bb06SSteffen Klassert } 52dff3bb06SSteffen Klassert 53dff3bb06SSteffen Klassert static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, 54dff3bb06SSteffen Klassert u8 *icv) 55dff3bb06SSteffen Klassert { 56dff3bb06SSteffen Klassert struct ahash_request *req; 57dff3bb06SSteffen Klassert 58dff3bb06SSteffen Klassert req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), 59dff3bb06SSteffen Klassert crypto_tfm_ctx_alignment()); 60dff3bb06SSteffen Klassert 61dff3bb06SSteffen Klassert ahash_request_set_tfm(req, ahash); 62dff3bb06SSteffen Klassert 63dff3bb06SSteffen Klassert return req; 64dff3bb06SSteffen Klassert } 65dff3bb06SSteffen Klassert 66dff3bb06SSteffen Klassert static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, 67dff3bb06SSteffen Klassert struct ahash_request *req) 68dff3bb06SSteffen Klassert { 69dff3bb06SSteffen Klassert return (void *)ALIGN((unsigned long)(req + 1) + 70dff3bb06SSteffen Klassert crypto_ahash_reqsize(ahash), 71dff3bb06SSteffen Klassert __alignof__(struct scatterlist)); 72dff3bb06SSteffen Klassert } 731da177e4SLinus Torvalds 741da177e4SLinus Torvalds /* Clear mutable options and find final destination to substitute 751da177e4SLinus Torvalds * into IP header for icv calculation. Options are already checked 761da177e4SLinus Torvalds * for validity, so paranoia is not required. */ 771da177e4SLinus Torvalds 78b71d1d42SEric Dumazet static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr) 791da177e4SLinus Torvalds { 801da177e4SLinus Torvalds unsigned char *optptr = (unsigned char *)(iph+1); 811da177e4SLinus Torvalds int l = iph->ihl*4 - sizeof(struct iphdr); 821da177e4SLinus Torvalds int optlen; 831da177e4SLinus Torvalds 841da177e4SLinus Torvalds while (l > 0) { 851da177e4SLinus Torvalds switch (*optptr) { 861da177e4SLinus Torvalds case IPOPT_END: 871da177e4SLinus Torvalds return 0; 881da177e4SLinus Torvalds case IPOPT_NOOP: 891da177e4SLinus Torvalds l--; 901da177e4SLinus Torvalds optptr++; 911da177e4SLinus Torvalds continue; 921da177e4SLinus Torvalds } 931da177e4SLinus Torvalds optlen = optptr[1]; 941da177e4SLinus Torvalds if (optlen<2 || optlen>l) 951da177e4SLinus Torvalds return -EINVAL; 961da177e4SLinus Torvalds switch (*optptr) { 971da177e4SLinus Torvalds case IPOPT_SEC: 981da177e4SLinus Torvalds case 0x85: /* Some "Extended Security" crap. */ 9911a03f78SPaul Moore case IPOPT_CIPSO: 1001da177e4SLinus Torvalds case IPOPT_RA: 1011da177e4SLinus Torvalds case 0x80|21: /* RFC1770 */ 1021da177e4SLinus Torvalds break; 1031da177e4SLinus Torvalds case IPOPT_LSRR: 1041da177e4SLinus Torvalds case IPOPT_SSRR: 1051da177e4SLinus Torvalds if (optlen < 6) 1061da177e4SLinus Torvalds return -EINVAL; 1071da177e4SLinus Torvalds memcpy(daddr, optptr+optlen-4, 4); 1081da177e4SLinus Torvalds /* Fall through */ 1091da177e4SLinus Torvalds default: 11096fe1c02SNick Bowler memset(optptr, 0, optlen); 1111da177e4SLinus Torvalds } 1121da177e4SLinus Torvalds l -= optlen; 1131da177e4SLinus Torvalds optptr += optlen; 1141da177e4SLinus Torvalds } 1151da177e4SLinus Torvalds return 0; 1161da177e4SLinus Torvalds } 1171da177e4SLinus Torvalds 118dff3bb06SSteffen Klassert static void ah_output_done(struct crypto_async_request *base, int err) 119dff3bb06SSteffen Klassert { 120dff3bb06SSteffen Klassert u8 *icv; 121dff3bb06SSteffen Klassert struct iphdr *iph; 122dff3bb06SSteffen Klassert struct sk_buff *skb = base->data; 123dff3bb06SSteffen Klassert struct xfrm_state *x = skb_dst(skb)->xfrm; 124dff3bb06SSteffen Klassert struct ah_data *ahp = x->data; 125dff3bb06SSteffen Klassert struct iphdr *top_iph = ip_hdr(skb); 126dff3bb06SSteffen Klassert struct ip_auth_hdr *ah = ip_auth_hdr(skb); 127dff3bb06SSteffen Klassert int ihl = ip_hdrlen(skb); 128dff3bb06SSteffen Klassert 129dff3bb06SSteffen Klassert iph = AH_SKB_CB(skb)->tmp; 130dff3bb06SSteffen Klassert icv = ah_tmp_icv(ahp->ahash, iph, ihl); 131dff3bb06SSteffen Klassert memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 132dff3bb06SSteffen Klassert 133dff3bb06SSteffen Klassert top_iph->tos = iph->tos; 134dff3bb06SSteffen Klassert top_iph->ttl = iph->ttl; 135dff3bb06SSteffen Klassert top_iph->frag_off = iph->frag_off; 136dff3bb06SSteffen Klassert if (top_iph->ihl != 5) { 137dff3bb06SSteffen Klassert top_iph->daddr = iph->daddr; 138dff3bb06SSteffen Klassert memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr)); 139dff3bb06SSteffen Klassert } 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 267b7ea81a5SNick Bowler err = ah->nexthdr; 268b7ea81a5SNick Bowler 269dff3bb06SSteffen Klassert skb->network_header += ah_hlen; 270dff3bb06SSteffen Klassert memcpy(skb_network_header(skb), work_iph, ihl); 271dff3bb06SSteffen Klassert __skb_pull(skb, ah_hlen + ihl); 272dff3bb06SSteffen Klassert skb_set_transport_header(skb, -ihl); 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 goto out_free; 375dff3bb06SSteffen Klassert } 376dff3bb06SSteffen Klassert 377dff3bb06SSteffen Klassert err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 378dff3bb06SSteffen Klassert if (err) 379dff3bb06SSteffen Klassert goto out_free; 380dff3bb06SSteffen Klassert 381b0e380b1SArnaldo Carvalho de Melo skb->network_header += ah_hlen; 382dff3bb06SSteffen Klassert memcpy(skb_network_header(skb), work_iph, ihl); 38331a4ab93SHerbert Xu __skb_pull(skb, ah_hlen + ihl); 384dff3bb06SSteffen Klassert skb_set_transport_header(skb, -ihl); 3851da177e4SLinus Torvalds 386dff3bb06SSteffen Klassert err = nexthdr; 3871da177e4SLinus Torvalds 388dff3bb06SSteffen Klassert out_free: 389dff3bb06SSteffen Klassert kfree (work_iph); 3901da177e4SLinus Torvalds out: 39107d4ee58SHerbert Xu return err; 3921da177e4SLinus Torvalds } 3931da177e4SLinus Torvalds 3941da177e4SLinus Torvalds static void ah4_err(struct sk_buff *skb, u32 info) 3951da177e4SLinus Torvalds { 3964fb236baSAlexey Dobriyan struct net *net = dev_net(skb->dev); 397b71d1d42SEric Dumazet const struct iphdr *iph = (const struct iphdr *)skb->data; 3981da177e4SLinus Torvalds struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); 3991da177e4SLinus Torvalds struct xfrm_state *x; 4001da177e4SLinus Torvalds 40155be7a9cSDavid S. Miller switch (icmp_hdr(skb)->type) { 40255be7a9cSDavid S. Miller case ICMP_DEST_UNREACH: 40355be7a9cSDavid S. Miller if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) 4041da177e4SLinus Torvalds return; 40555be7a9cSDavid S. Miller case ICMP_REDIRECT: 40655be7a9cSDavid S. Miller break; 40755be7a9cSDavid S. Miller default: 40855be7a9cSDavid S. Miller return; 40955be7a9cSDavid S. Miller } 4101da177e4SLinus Torvalds 411b71d1d42SEric Dumazet x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 412b71d1d42SEric Dumazet ah->spi, IPPROTO_AH, AF_INET); 4131da177e4SLinus Torvalds if (!x) 4141da177e4SLinus Torvalds return; 41555be7a9cSDavid S. Miller 41655be7a9cSDavid S. Miller if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) 41736393395SDavid S. Miller ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_AH, 0); 41855be7a9cSDavid S. Miller else 41955be7a9cSDavid S. Miller ipv4_redirect(skb, net, 0, 0, IPPROTO_AH, 0); 4201da177e4SLinus Torvalds xfrm_state_put(x); 4211da177e4SLinus Torvalds } 4221da177e4SLinus Torvalds 42372cb6962SHerbert Xu static int ah_init_state(struct xfrm_state *x) 4241da177e4SLinus Torvalds { 4251da177e4SLinus Torvalds struct ah_data *ahp = NULL; 4261da177e4SLinus Torvalds struct xfrm_algo_desc *aalg_desc; 427dff3bb06SSteffen Klassert struct crypto_ahash *ahash; 4281da177e4SLinus Torvalds 4291da177e4SLinus Torvalds if (!x->aalg) 4301da177e4SLinus Torvalds goto error; 4311da177e4SLinus Torvalds 4321da177e4SLinus Torvalds if (x->encap) 4331da177e4SLinus Torvalds goto error; 4341da177e4SLinus Torvalds 4350da974f4SPanagiotis Issaris ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); 436dff3bb06SSteffen Klassert if (!ahp) 4371da177e4SLinus Torvalds return -ENOMEM; 4381da177e4SLinus Torvalds 439dff3bb06SSteffen Klassert ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); 440dff3bb06SSteffen Klassert if (IS_ERR(ahash)) 4411da177e4SLinus Torvalds goto error; 44207d4ee58SHerbert Xu 443dff3bb06SSteffen Klassert ahp->ahash = ahash; 444dff3bb06SSteffen Klassert if (crypto_ahash_setkey(ahash, x->aalg->alg_key, 445bc31d3b2SHerbert Xu (x->aalg->alg_key_len + 7) / 8)) 44607d4ee58SHerbert Xu goto error; 4471da177e4SLinus Torvalds 4481da177e4SLinus Torvalds /* 4491da177e4SLinus Torvalds * Lookup the algorithm description maintained by xfrm_algo, 4501da177e4SLinus Torvalds * verify crypto transform properties, and store information 4511da177e4SLinus Torvalds * we need for AH processing. This lookup cannot fail here 452dff3bb06SSteffen Klassert * after a successful crypto_alloc_ahash(). 4531da177e4SLinus Torvalds */ 4541da177e4SLinus Torvalds aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 4551da177e4SLinus Torvalds BUG_ON(!aalg_desc); 4561da177e4SLinus Torvalds 4571da177e4SLinus Torvalds if (aalg_desc->uinfo.auth.icv_fullbits/8 != 458dff3bb06SSteffen Klassert crypto_ahash_digestsize(ahash)) { 459afd46503SJoe Perches pr_info("%s: %s digestsize %u != %hu\n", 460afd46503SJoe Perches __func__, x->aalg->alg_name, 461afd46503SJoe Perches crypto_ahash_digestsize(ahash), 4621da177e4SLinus Torvalds aalg_desc->uinfo.auth.icv_fullbits / 8); 4631da177e4SLinus Torvalds goto error; 4641da177e4SLinus Torvalds } 4651da177e4SLinus Torvalds 4661da177e4SLinus Torvalds ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; 4678f8a088cSMartin Willi ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; 4681da177e4SLinus Torvalds 4691da177e4SLinus Torvalds BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN); 4701da177e4SLinus Torvalds 471fa9921e4SNicolas Dichtel if (x->props.flags & XFRM_STATE_ALIGN4) 472fa9921e4SNicolas Dichtel x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) + 473fa9921e4SNicolas Dichtel ahp->icv_trunc_len); 474fa9921e4SNicolas Dichtel else 47587bdc48dSHerbert Xu x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + 47687bdc48dSHerbert Xu ahp->icv_trunc_len); 4777e49e6deSMasahide NAKAMURA if (x->props.mode == XFRM_MODE_TUNNEL) 4781da177e4SLinus Torvalds x->props.header_len += sizeof(struct iphdr); 4791da177e4SLinus Torvalds x->data = ahp; 4801da177e4SLinus Torvalds 4811da177e4SLinus Torvalds return 0; 4821da177e4SLinus Torvalds 4831da177e4SLinus Torvalds error: 4841da177e4SLinus Torvalds if (ahp) { 485dff3bb06SSteffen Klassert crypto_free_ahash(ahp->ahash); 4861da177e4SLinus Torvalds kfree(ahp); 4871da177e4SLinus Torvalds } 4881da177e4SLinus Torvalds return -EINVAL; 4891da177e4SLinus Torvalds } 4901da177e4SLinus Torvalds 4911da177e4SLinus Torvalds static void ah_destroy(struct xfrm_state *x) 4921da177e4SLinus Torvalds { 4931da177e4SLinus Torvalds struct ah_data *ahp = x->data; 4941da177e4SLinus Torvalds 4951da177e4SLinus Torvalds if (!ahp) 4961da177e4SLinus Torvalds return; 4971da177e4SLinus Torvalds 498dff3bb06SSteffen Klassert crypto_free_ahash(ahp->ahash); 4991da177e4SLinus Torvalds kfree(ahp); 5001da177e4SLinus Torvalds } 5011da177e4SLinus Torvalds 5021da177e4SLinus Torvalds 503533cb5b0SEric Dumazet static const struct xfrm_type ah_type = 5041da177e4SLinus Torvalds { 5051da177e4SLinus Torvalds .description = "AH4", 5061da177e4SLinus Torvalds .owner = THIS_MODULE, 5071da177e4SLinus Torvalds .proto = IPPROTO_AH, 508436a0a40SHerbert Xu .flags = XFRM_TYPE_REPLAY_PROT, 5091da177e4SLinus Torvalds .init_state = ah_init_state, 5101da177e4SLinus Torvalds .destructor = ah_destroy, 5111da177e4SLinus Torvalds .input = ah_input, 5121da177e4SLinus Torvalds .output = ah_output 5131da177e4SLinus Torvalds }; 5141da177e4SLinus Torvalds 51532613090SAlexey Dobriyan static const struct net_protocol ah4_protocol = { 5161da177e4SLinus Torvalds .handler = xfrm4_rcv, 5171da177e4SLinus Torvalds .err_handler = ah4_err, 5181da177e4SLinus Torvalds .no_policy = 1, 5194fb236baSAlexey Dobriyan .netns_ok = 1, 5201da177e4SLinus Torvalds }; 5211da177e4SLinus Torvalds 5221da177e4SLinus Torvalds static int __init ah4_init(void) 5231da177e4SLinus Torvalds { 5241da177e4SLinus Torvalds if (xfrm_register_type(&ah_type, AF_INET) < 0) { 525058bd4d2SJoe Perches pr_info("%s: can't add xfrm type\n", __func__); 5261da177e4SLinus Torvalds return -EAGAIN; 5271da177e4SLinus Torvalds } 5281da177e4SLinus Torvalds if (inet_add_protocol(&ah4_protocol, IPPROTO_AH) < 0) { 529058bd4d2SJoe Perches pr_info("%s: can't add protocol\n", __func__); 5301da177e4SLinus Torvalds xfrm_unregister_type(&ah_type, AF_INET); 5311da177e4SLinus Torvalds return -EAGAIN; 5321da177e4SLinus Torvalds } 5331da177e4SLinus Torvalds return 0; 5341da177e4SLinus Torvalds } 5351da177e4SLinus Torvalds 5361da177e4SLinus Torvalds static void __exit ah4_fini(void) 5371da177e4SLinus Torvalds { 5381da177e4SLinus Torvalds if (inet_del_protocol(&ah4_protocol, IPPROTO_AH) < 0) 539058bd4d2SJoe Perches pr_info("%s: can't remove protocol\n", __func__); 5401da177e4SLinus Torvalds if (xfrm_unregister_type(&ah_type, AF_INET) < 0) 541058bd4d2SJoe Perches pr_info("%s: can't remove xfrm type\n", __func__); 5421da177e4SLinus Torvalds } 5431da177e4SLinus Torvalds 5441da177e4SLinus Torvalds module_init(ah4_init); 5451da177e4SLinus Torvalds module_exit(ah4_fini); 5461da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 547d3d6dd3aSMasahide NAKAMURA MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_AH); 548