/* $NetBSD: ah_core.c,v 1.18 2000/06/02 18:20:15 itojun Exp $ */ /* $KAME: ah_core.c,v 1.34 2000/05/29 08:05:02 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * RFC1826/2402 authentication header. */ #include "opt_inet.h" #include "opt_ipsec.h" /* Some of operating systems have standard crypto checksum library */ #ifdef __NetBSD__ #define HAVE_MD5 #define HAVE_SHA1 #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #include #include #endif #include #include #ifdef IPSEC_ESP #include #endif #include #include #ifdef HAVE_MD5 #include #else #include #endif #ifdef HAVE_SHA1 #include #define SHA1_RESULTLEN 20 #else #include #endif #include #define HMACSIZE 16 static int ah_sumsiz_1216 __P((struct secasvar *)); static int ah_sumsiz_zero __P((struct secasvar *)); static int ah_none_mature __P((struct secasvar *)); static int ah_none_init __P((struct ah_algorithm_state *, struct secasvar *)); static void ah_none_loop __P((struct ah_algorithm_state *, caddr_t, size_t)); static void ah_none_result __P((struct ah_algorithm_state *, caddr_t)); static int ah_keyed_md5_mature __P((struct secasvar *)); static int ah_keyed_md5_init __P((struct ah_algorithm_state *, struct secasvar *)); static void ah_keyed_md5_loop __P((struct ah_algorithm_state *, caddr_t, size_t)); static void ah_keyed_md5_result __P((struct ah_algorithm_state *, caddr_t)); static int ah_keyed_sha1_mature __P((struct secasvar *)); static int ah_keyed_sha1_init __P((struct ah_algorithm_state *, struct secasvar *)); static void ah_keyed_sha1_loop __P((struct ah_algorithm_state *, caddr_t, size_t)); static void ah_keyed_sha1_result __P((struct ah_algorithm_state *, caddr_t)); static int ah_hmac_md5_mature __P((struct secasvar *)); static int ah_hmac_md5_init __P((struct ah_algorithm_state *, struct secasvar *)); static void ah_hmac_md5_loop __P((struct ah_algorithm_state *, caddr_t, size_t)); static void ah_hmac_md5_result __P((struct ah_algorithm_state *, caddr_t)); static int ah_hmac_sha1_mature __P((struct secasvar *)); static int ah_hmac_sha1_init __P((struct ah_algorithm_state *, struct secasvar *)); static void ah_hmac_sha1_loop __P((struct ah_algorithm_state *, caddr_t, size_t)); static void ah_hmac_sha1_result __P((struct ah_algorithm_state *, caddr_t)); static void ah_update_mbuf __P((struct mbuf *, int, int, struct ah_algorithm *, struct ah_algorithm_state *)); /* checksum algorithms */ /* NOTE: The order depends on SADB_AALG_x in net/pfkeyv2.h */ struct ah_algorithm ah_algorithms[] = { { 0, 0, 0, 0, 0, 0, }, { ah_sumsiz_1216, ah_hmac_md5_mature, 128, 128, ah_hmac_md5_init, ah_hmac_md5_loop, ah_hmac_md5_result, }, { ah_sumsiz_1216, ah_hmac_sha1_mature, 160, 160, ah_hmac_sha1_init, ah_hmac_sha1_loop, ah_hmac_sha1_result, }, { ah_sumsiz_1216, ah_keyed_md5_mature, 128, 128, ah_keyed_md5_init, ah_keyed_md5_loop, ah_keyed_md5_result, }, { ah_sumsiz_1216, ah_keyed_sha1_mature, 160, 160, ah_keyed_sha1_init, ah_keyed_sha1_loop, ah_keyed_sha1_result, }, { ah_sumsiz_zero, ah_none_mature, 0, 2048, ah_none_init, ah_none_loop, ah_none_result, }, }; static int ah_sumsiz_1216(sav) struct secasvar *sav; { if (!sav) return -1; if (sav->flags & SADB_X_EXT_OLD) return 16; else return 12; } static int ah_sumsiz_zero(sav) struct secasvar *sav; { if (!sav) return -1; return 0; } static int ah_none_mature(sav) struct secasvar *sav; { if (sav->sah->saidx.proto == IPPROTO_AH) { ipseclog((LOG_ERR, "ah_none_mature: protocol and algorithm mismatch.\n")); return 1; } return 0; } static int ah_none_init(state, sav) struct ah_algorithm_state *state; struct secasvar *sav; { state->foo = NULL; return 0; } static void ah_none_loop(state, addr, len) struct ah_algorithm_state *state; caddr_t addr; size_t len; { } static void ah_none_result(state, addr) struct ah_algorithm_state *state; caddr_t addr; { } static int ah_keyed_md5_mature(sav) struct secasvar *sav; { /* anything is okay */ return 0; } static int ah_keyed_md5_init(state, sav) struct ah_algorithm_state *state; struct secasvar *sav; { size_t padlen; size_t keybitlen; u_int8_t buf[32]; if (!state) panic("ah_keyed_md5_init: what?"); state->sav = sav; state->foo = (void *)malloc(sizeof(MD5_CTX), M_TEMP, M_NOWAIT); if (state->foo == NULL) return ENOBUFS; MD5Init((MD5_CTX *)state->foo); if (state->sav) { MD5Update((MD5_CTX *)state->foo, (u_int8_t *)_KEYBUF(state->sav->key_auth), (u_int)_KEYLEN(state->sav->key_auth)); /* * Pad after the key. * We cannot simply use md5_pad() since the function * won't update the total length. */ if (_KEYLEN(state->sav->key_auth) < 56) padlen = 64 - 8 - _KEYLEN(state->sav->key_auth); else padlen = 64 + 64 - 8 - _KEYLEN(state->sav->key_auth); keybitlen = _KEYLEN(state->sav->key_auth); keybitlen *= 8; buf[0] = 0x80; MD5Update((MD5_CTX *)state->foo, &buf[0], 1); padlen--; bzero(buf, sizeof(buf)); while (sizeof(buf) < padlen) { MD5Update((MD5_CTX *)state->foo, &buf[0], sizeof(buf)); padlen -= sizeof(buf); } if (padlen) { MD5Update((MD5_CTX *)state->foo, &buf[0], padlen); } buf[0] = (keybitlen >> 0) & 0xff; buf[1] = (keybitlen >> 8) & 0xff; buf[2] = (keybitlen >> 16) & 0xff; buf[3] = (keybitlen >> 24) & 0xff; MD5Update((MD5_CTX *)state->foo, buf, 8); } return 0; } static void ah_keyed_md5_loop(state, addr, len) struct ah_algorithm_state *state; caddr_t addr; size_t len; { if (!state) panic("ah_keyed_md5_loop: what?"); MD5Update((MD5_CTX *)state->foo, addr, len); } static void ah_keyed_md5_result(state, addr) struct ah_algorithm_state *state; caddr_t addr; { u_char digest[16]; if (!state) panic("ah_keyed_md5_result: what?"); if (state->sav) { MD5Update((MD5_CTX *)state->foo, (u_int8_t *)_KEYBUF(state->sav->key_auth), (u_int)_KEYLEN(state->sav->key_auth)); } MD5Final(&digest[0], (MD5_CTX *)state->foo); free(state->foo, M_TEMP); bcopy(&digest[0], (void *)addr, sizeof(digest)); } static int ah_keyed_sha1_mature(sav) struct secasvar *sav; { struct ah_algorithm *algo; if (!sav->key_auth) { ipseclog((LOG_ERR, "ah_keyed_sha1_mature: no key is given.\n")); return 1; } algo = &ah_algorithms[sav->alg_auth]; if (sav->key_auth->sadb_key_bits < algo->keymin || algo->keymax < sav->key_auth->sadb_key_bits) { ipseclog((LOG_ERR, "ah_keyed_sha1_mature: invalid key length %d.\n", sav->key_auth->sadb_key_bits)); return 1; } return 0; } static int ah_keyed_sha1_init(state, sav) struct ah_algorithm_state *state; struct secasvar *sav; { SHA1_CTX *ctxt; size_t padlen; size_t keybitlen; u_int8_t buf[32]; if (!state) panic("ah_keyed_sha1_init: what?"); state->sav = sav; state->foo = (void *)malloc(sizeof(SHA1_CTX), M_TEMP, M_NOWAIT); if (!state->foo) return ENOBUFS; ctxt = (SHA1_CTX *)state->foo; SHA1Init(ctxt); if (state->sav) { SHA1Update(ctxt, (u_int8_t *)_KEYBUF(state->sav->key_auth), (u_int)_KEYLEN(state->sav->key_auth)); /* * Pad after the key. */ if (_KEYLEN(state->sav->key_auth) < 56) padlen = 64 - 8 - _KEYLEN(state->sav->key_auth); else padlen = 64 + 64 - 8 - _KEYLEN(state->sav->key_auth); keybitlen = _KEYLEN(state->sav->key_auth); keybitlen *= 8; buf[0] = 0x80; SHA1Update(ctxt, &buf[0], 1); padlen--; bzero(buf, sizeof(buf)); while (sizeof(buf) < padlen) { SHA1Update(ctxt, &buf[0], sizeof(buf)); padlen -= sizeof(buf); } if (padlen) { SHA1Update(ctxt, &buf[0], padlen); } buf[0] = (keybitlen >> 0) & 0xff; buf[1] = (keybitlen >> 8) & 0xff; buf[2] = (keybitlen >> 16) & 0xff; buf[3] = (keybitlen >> 24) & 0xff; SHA1Update(ctxt, buf, 8); } return 0; } static void ah_keyed_sha1_loop(state, addr, len) struct ah_algorithm_state *state; caddr_t addr; size_t len; { SHA1_CTX *ctxt; if (!state || !state->foo) panic("ah_keyed_sha1_loop: what?"); ctxt = (SHA1_CTX *)state->foo; SHA1Update(ctxt, (caddr_t)addr, (size_t)len); } static void ah_keyed_sha1_result(state, addr) struct ah_algorithm_state *state; caddr_t addr; { u_char digest[SHA1_RESULTLEN]; /* SHA-1 generates 160 bits */ SHA1_CTX *ctxt; if (!state || !state->foo) panic("ah_keyed_sha1_result: what?"); ctxt = (SHA1_CTX *)state->foo; if (state->sav) { SHA1Update(ctxt, (u_int8_t *)_KEYBUF(state->sav->key_auth), (u_int)_KEYLEN(state->sav->key_auth)); } SHA1Final((caddr_t)&digest[0], ctxt); bcopy(&digest[0], (void *)addr, HMACSIZE); free(state->foo, M_TEMP); } static int ah_hmac_md5_mature(sav) struct secasvar *sav; { struct ah_algorithm *algo; if (!sav->key_auth) { ipseclog((LOG_ERR, "ah_hmac_md5_mature: no key is given.\n")); return 1; } algo = &ah_algorithms[sav->alg_auth]; if (sav->key_auth->sadb_key_bits < algo->keymin || algo->keymax < sav->key_auth->sadb_key_bits) { ipseclog((LOG_ERR, "ah_hmac_md5_mature: invalid key length %d.\n", sav->key_auth->sadb_key_bits)); return 1; } return 0; } static int ah_hmac_md5_init(state, sav) struct ah_algorithm_state *state; struct secasvar *sav; { u_char *ipad; u_char *opad; u_char tk[16]; u_char *key; size_t keylen; size_t i; MD5_CTX *ctxt; if (!state) panic("ah_hmac_md5_init: what?"); state->sav = sav; state->foo = (void *)malloc(64 + 64 + sizeof(MD5_CTX), M_TEMP, M_NOWAIT); if (!state->foo) return ENOBUFS; ipad = (u_char *)state->foo; opad = (u_char *)(ipad + 64); ctxt = (MD5_CTX *)(opad + 64); /* compress the key if necessery */ if (64 < _KEYLEN(state->sav->key_auth)) { MD5Init(ctxt); MD5Update(ctxt, _KEYBUF(state->sav->key_auth), _KEYLEN(state->sav->key_auth)); MD5Final(&tk[0], ctxt); key = &tk[0]; keylen = 16; } else { key = _KEYBUF(state->sav->key_auth); keylen = _KEYLEN(state->sav->key_auth); } bzero(ipad, 64); bzero(opad, 64); bcopy(key, ipad, keylen); bcopy(key, opad, keylen); for (i = 0; i < 64; i++) { ipad[i] ^= 0x36; opad[i] ^= 0x5c; } MD5Init(ctxt); MD5Update(ctxt, ipad, 64); return 0; } static void ah_hmac_md5_loop(state, addr, len) struct ah_algorithm_state *state; caddr_t addr; size_t len; { MD5_CTX *ctxt; if (!state || !state->foo) panic("ah_hmac_md5_loop: what?"); ctxt = (MD5_CTX *)(((caddr_t)state->foo) + 128); MD5Update(ctxt, addr, len); } static void ah_hmac_md5_result(state, addr) struct ah_algorithm_state *state; caddr_t addr; { u_char digest[16]; u_char *ipad; u_char *opad; MD5_CTX *ctxt; if (!state || !state->foo) panic("ah_hmac_md5_result: what?"); ipad = (u_char *)state->foo; opad = (u_char *)(ipad + 64); ctxt = (MD5_CTX *)(opad + 64); MD5Final(&digest[0], ctxt); MD5Init(ctxt); MD5Update(ctxt, opad, 64); MD5Update(ctxt, &digest[0], sizeof(digest)); MD5Final(&digest[0], ctxt); bcopy(&digest[0], (void *)addr, HMACSIZE); free(state->foo, M_TEMP); } static int ah_hmac_sha1_mature(sav) struct secasvar *sav; { struct ah_algorithm *algo; if (!sav->key_auth) { ipseclog((LOG_ERR, "ah_hmac_sha1_mature: no key is given.\n")); return 1; } algo = &ah_algorithms[sav->alg_auth]; if (sav->key_auth->sadb_key_bits < algo->keymin || algo->keymax < sav->key_auth->sadb_key_bits) { ipseclog((LOG_ERR, "ah_hmac_sha1_mature: invalid key length %d.\n", sav->key_auth->sadb_key_bits)); return 1; } return 0; } static int ah_hmac_sha1_init(state, sav) struct ah_algorithm_state *state; struct secasvar *sav; { u_char *ipad; u_char *opad; SHA1_CTX *ctxt; u_char tk[SHA1_RESULTLEN]; /* SHA-1 generates 160 bits */ u_char *key; size_t keylen; size_t i; if (!state) panic("ah_hmac_sha1_init: what?"); state->sav = sav; state->foo = (void *)malloc(64 + 64 + sizeof(SHA1_CTX), M_TEMP, M_NOWAIT); if (!state->foo) return ENOBUFS; ipad = (u_char *)state->foo; opad = (u_char *)(ipad + 64); ctxt = (SHA1_CTX *)(opad + 64); /* compress the key if necessery */ if (64 < _KEYLEN(state->sav->key_auth)) { SHA1Init(ctxt); SHA1Update(ctxt, _KEYBUF(state->sav->key_auth), _KEYLEN(state->sav->key_auth)); SHA1Final(&tk[0], ctxt); key = &tk[0]; keylen = SHA1_RESULTLEN; } else { key = _KEYBUF(state->sav->key_auth); keylen = _KEYLEN(state->sav->key_auth); } bzero(ipad, 64); bzero(opad, 64); bcopy(key, ipad, keylen); bcopy(key, opad, keylen); for (i = 0; i < 64; i++) { ipad[i] ^= 0x36; opad[i] ^= 0x5c; } SHA1Init(ctxt); SHA1Update(ctxt, ipad, 64); return 0; } static void ah_hmac_sha1_loop(state, addr, len) struct ah_algorithm_state *state; caddr_t addr; size_t len; { SHA1_CTX *ctxt; if (!state || !state->foo) panic("ah_hmac_sha1_loop: what?"); ctxt = (SHA1_CTX *)(((u_char *)state->foo) + 128); SHA1Update(ctxt, (caddr_t)addr, (size_t)len); } static void ah_hmac_sha1_result(state, addr) struct ah_algorithm_state *state; caddr_t addr; { u_char digest[SHA1_RESULTLEN]; /* SHA-1 generates 160 bits */ u_char *ipad; u_char *opad; SHA1_CTX *ctxt; if (!state || !state->foo) panic("ah_hmac_sha1_result: what?"); ipad = (u_char *)state->foo; opad = (u_char *)(ipad + 64); ctxt = (SHA1_CTX *)(opad + 64); SHA1Final((caddr_t)&digest[0], ctxt); SHA1Init(ctxt); SHA1Update(ctxt, opad, 64); SHA1Update(ctxt, (caddr_t)&digest[0], sizeof(digest)); SHA1Final((caddr_t)&digest[0], ctxt); bcopy(&digest[0], (void *)addr, HMACSIZE); free(state->foo, M_TEMP); } /*------------------------------------------------------------*/ /* * go generate the checksum. */ static void ah_update_mbuf(m, off, len, algo, algos) struct mbuf *m; int off; int len; struct ah_algorithm *algo; struct ah_algorithm_state *algos; { struct mbuf *n; int tlen; /* easy case first */ if (off + len <= m->m_len) { (algo->update)(algos, mtod(m, caddr_t) + off, len); return; } for (n = m; n; n = n->m_next) { if (off < n->m_len) break; off -= n->m_len; } if (!n) panic("ah_update_mbuf: wrong offset specified"); for (/*nothing*/; n && len > 0; n = n->m_next) { if (n->m_len == 0) continue; if (n->m_len - off < len) tlen = n->m_len - off; else tlen = len; (algo->update)(algos, mtod(n, caddr_t) + off, tlen); len -= tlen; off = 0; } } /* * Go generate the checksum. This function won't modify the mbuf chain * except AH itself. * * NOTE: the function does not free mbuf on failure. * Don't use m_copy(), it will try to share cluster mbuf by using refcnt. */ int ah4_calccksum(m, ahdat, len, algo, sav) struct mbuf *m; caddr_t ahdat; size_t len; struct ah_algorithm *algo; struct secasvar *sav; { int off; int hdrtype; size_t advancewidth; struct ah_algorithm_state algos; u_char sumbuf[AH_MAXSUMSIZE]; int error = 0; int ahseen; struct mbuf *n = NULL; if ((m->m_flags & M_PKTHDR) == 0) return EINVAL; ahseen = 0; hdrtype = -1; /*dummy, it is called IPPROTO_IP*/ off = 0; error = (algo->init)(&algos, sav); if (error) return error; advancewidth = 0; /*safety*/ again: /* gory. */ switch (hdrtype) { case -1: /*first one only*/ { /* * copy ip hdr, modify to fit the AH checksum rule, * then take a checksum. */ struct ip iphdr; size_t hlen; m_copydata(m, off, sizeof(iphdr), (caddr_t)&iphdr); #ifdef _IP_VHL hlen = IP_VHL_HL(iphdr.ip_vhl) << 2; #else hlen = iphdr.ip_hl << 2; #endif iphdr.ip_ttl = 0; iphdr.ip_sum = htons(0); if (ip4_ah_cleartos) iphdr.ip_tos = 0; iphdr.ip_off = htons(ntohs(iphdr.ip_off) & ip4_ah_offsetmask); (algo->update)(&algos, (caddr_t)&iphdr, sizeof(struct ip)); if (hlen != sizeof(struct ip)) { u_char *p; int i, l, skip; if (hlen > MCLBYTES) { error = EMSGSIZE; goto fail; } MGET(n, M_DONTWAIT, MT_DATA); if (n && hlen > MLEN) { MCLGET(n, M_DONTWAIT); if ((n->m_flags & M_EXT) == 0) { m_free(n); n = NULL; } } if (n == NULL) { error = ENOBUFS; goto fail; } m_copydata(m, off, hlen, mtod(n, caddr_t)); /* * IP options processing. * See RFC2402 appendix A. */ p = mtod(n, u_char *); i = sizeof(struct ip); while (i < hlen) { skip = 1; switch (p[i + IPOPT_OPTVAL]) { case IPOPT_EOL: case IPOPT_NOP: l = 1; skip = 0; break; case IPOPT_SECURITY: /* 0x82 */ case 0x85: /* Extended security */ case 0x86: /* Commercial security */ case 0x94: /* Router alert */ case 0x95: /* RFC1770 */ l = p[i + IPOPT_OLEN]; skip = 0; break; default: l = p[i + IPOPT_OLEN]; skip = 1; break; } if (l <= 0 || hlen - i < l) { ipseclog((LOG_ERR, "ah4_calccksum: invalid IP option " "(type=%02x len=%02x)\n", p[i + IPOPT_OPTVAL], p[i + IPOPT_OLEN])); m_free(n); n = NULL; error = EINVAL; goto fail; } if (skip) bzero(p + i, l); if (p[i + IPOPT_OPTVAL] == IPOPT_EOL) break; i += l; } p = mtod(n, u_char *) + sizeof(struct ip); (algo->update)(&algos, p, hlen - sizeof(struct ip)); m_free(n); n = NULL; } hdrtype = (iphdr.ip_p) & 0xff; advancewidth = hlen; break; } case IPPROTO_AH: { struct ah ah; int siz; int hdrsiz; int totlen; m_copydata(m, off, sizeof(ah), (caddr_t)&ah); hdrsiz = (sav->flags & SADB_X_EXT_OLD) ? sizeof(struct ah) : sizeof(struct newah); siz = (*algo->sumsiz)(sav); totlen = (ah.ah_len + 2) << 2; /* * special treatment is necessary for the first one, not others */ if (!ahseen) { if (totlen > m->m_pkthdr.len - off || totlen > MCLBYTES) { error = EMSGSIZE; goto fail; } MGET(n, M_DONTWAIT, MT_DATA); if (n && totlen > MLEN) { MCLGET(n, M_DONTWAIT); if ((n->m_flags & M_EXT) == 0) { m_free(n); n = NULL; } } if (n == NULL) { error = ENOBUFS; goto fail; } m_copydata(m, off, totlen, mtod(n, caddr_t)); n->m_len = totlen; bzero(mtod(n, caddr_t) + hdrsiz, siz); (algo->update)(&algos, mtod(n, caddr_t), n->m_len); m_free(n); n = NULL; } else ah_update_mbuf(m, off, totlen, algo, &algos); ahseen++; hdrtype = ah.ah_nxt; advancewidth = totlen; break; } default: ah_update_mbuf(m, off, m->m_pkthdr.len - off, algo, &algos); advancewidth = m->m_pkthdr.len - off; break; } off += advancewidth; if (off < m->m_pkthdr.len) goto again; if (len < (*algo->sumsiz)(sav)) { error = EINVAL; goto fail; } (algo->result)(&algos, &sumbuf[0]); bcopy(&sumbuf[0], ahdat, (*algo->sumsiz)(sav)); if (n) m_free(n); return error; fail: if (n) m_free(n); return error; } #ifdef INET6 /* * Go generate the checksum. This function won't modify the mbuf chain * except AH itself. * * NOTE: the function does not free mbuf on failure. * Don't use m_copy(), it will try to share cluster mbuf by using refcnt. */ int ah6_calccksum(m, ahdat, len, algo, sav) struct mbuf *m; caddr_t ahdat; size_t len; struct ah_algorithm *algo; struct secasvar *sav; { int newoff, off; int proto, nxt; struct mbuf *n = NULL; int error; int ahseen; struct ah_algorithm_state algos; u_char sumbuf[AH_MAXSUMSIZE]; if ((m->m_flags & M_PKTHDR) == 0) return EINVAL; error = (algo->init)(&algos, sav); if (error) return error; off = 0; proto = IPPROTO_IPV6; nxt = -1; ahseen = 0; again: newoff = ip6_nexthdr(m, off, proto, &nxt); if (newoff < 0) newoff = m->m_pkthdr.len; else if (newoff <= off) { error = EINVAL; goto fail; } switch (proto) { case IPPROTO_IPV6: /* * special treatment is necessary for the first one, not others */ if (off == 0) { struct ip6_hdr ip6copy; if (newoff - off != sizeof(struct ip6_hdr)) { error = EINVAL; goto fail; } m_copydata(m, off, newoff - off, (caddr_t)&ip6copy); /* RFC2402 */ ip6copy.ip6_flow = 0; ip6copy.ip6_vfc &= ~IPV6_VERSION_MASK; ip6copy.ip6_vfc |= IPV6_VERSION; ip6copy.ip6_hlim = 0; if (IN6_IS_ADDR_LINKLOCAL(&ip6copy.ip6_src)) ip6copy.ip6_src.s6_addr16[1] = 0x0000; if (IN6_IS_ADDR_LINKLOCAL(&ip6copy.ip6_dst)) ip6copy.ip6_dst.s6_addr16[1] = 0x0000; (algo->update)(&algos, (caddr_t)&ip6copy, sizeof(struct ip6_hdr)); } else { newoff = m->m_pkthdr.len; ah_update_mbuf(m, off, m->m_pkthdr.len - off, algo, &algos); } break; case IPPROTO_AH: { int siz; int hdrsiz; hdrsiz = (sav->flags & SADB_X_EXT_OLD) ? sizeof(struct ah) : sizeof(struct newah); siz = (*algo->sumsiz)(sav); /* * special treatment is necessary for the first one, not others */ if (!ahseen) { if (newoff - off > MCLBYTES) { error = EMSGSIZE; goto fail; } MGET(n, M_DONTWAIT, MT_DATA); if (n && newoff - off > MLEN) { MCLGET(n, M_DONTWAIT); if ((n->m_flags & M_EXT) == 0) { m_free(n); n = NULL; } } if (n == NULL) { error = ENOBUFS; goto fail; } m_copydata(m, off, newoff - off, mtod(n, caddr_t)); n->m_len = newoff - off; bzero(mtod(n, caddr_t) + hdrsiz, siz); (algo->update)(&algos, mtod(n, caddr_t), n->m_len); m_free(n); n = NULL; } else ah_update_mbuf(m, off, newoff - off, algo, &algos); ahseen++; break; } case IPPROTO_HOPOPTS: case IPPROTO_DSTOPTS: { struct ip6_ext *ip6e; int hdrlen, optlen; u_int8_t *p, *optend, *optp; if (newoff - off > MCLBYTES) { error = EMSGSIZE; goto fail; } MGET(n, M_DONTWAIT, MT_DATA); if (n && newoff - off > MLEN) { MCLGET(n, M_DONTWAIT); if ((n->m_flags & M_EXT) == 0) { m_free(n); n = NULL; } } if (n == NULL) { error = ENOBUFS; goto fail; } m_copydata(m, off, newoff - off, mtod(n, caddr_t)); n->m_len = newoff - off; ip6e = mtod(n, struct ip6_ext *); hdrlen = (ip6e->ip6e_len + 1) << 3; if (newoff - off < hdrlen) { error = EINVAL; m_free(n); n = NULL; goto fail; } p = mtod(n, u_int8_t *); optend = p + hdrlen; /* * ICV calculation for the options header including all * options. This part is a little tricky since there are * two type of options; mutable and immutable. We try to * null-out mutable ones here. */ optp = p + 2; while (optp < optend) { if (optp[0] == IP6OPT_PAD1) optlen = 1; else { if (optp + 2 > optend) { error = EINVAL; m_free(n); n = NULL; goto fail; } optlen = optp[1] + 2; if (optp[0] & IP6OPT_MUTABLE) bzero(optp + 2, optlen - 2); } optp += optlen; } (algo->update)(&algos, mtod(n, caddr_t), n->m_len); m_free(n); n = NULL; break; } case IPPROTO_ROUTING: /* * For an input packet, we can just calculate `as is'. * For an output packet, we assume ip6_output have already * made packet how it will be received at the final * destination. */ /* FALLTHROUGH */ default: ah_update_mbuf(m, off, newoff - off, algo, &algos); break; } if (newoff < m->m_pkthdr.len) { proto = nxt; off = newoff; goto again; } if (len < (*algo->sumsiz)(sav)) { error = EINVAL; goto fail; } (algo->result)(&algos, &sumbuf[0]); bcopy(&sumbuf[0], ahdat, (*algo->sumsiz)(sav)); /* just in case */ if (n) m_free(n); return 0; fail: /* just in case */ if (n) m_free(n); return error; } #endif