diff options
Diffstat (limited to 'sys/netipsec/xform_esp.c')
-rw-r--r-- | sys/netipsec/xform_esp.c | 171 |
1 files changed, 90 insertions, 81 deletions
diff --git a/sys/netipsec/xform_esp.c b/sys/netipsec/xform_esp.c index 18953f9..f1c1eaf 100644 --- a/sys/netipsec/xform_esp.c +++ b/sys/netipsec/xform_esp.c @@ -46,6 +46,9 @@ #include <sys/kernel.h> #include <sys/random.h> #include <sys/sysctl.h> +#include <sys/lock.h> +#include <sys/mutex.h> +#include <machine/atomic.h> #include <net/if.h> #include <net/vnet.h> @@ -180,12 +183,14 @@ esp_init(struct secasvar *sav, struct xformsw *xsp) __func__, txform->name)); return EINVAL; } - if ((sav->flags&(SADB_X_EXT_OLD|SADB_X_EXT_IV4B)) == SADB_X_EXT_IV4B) { + if ((sav->flags & (SADB_X_EXT_OLD | SADB_X_EXT_IV4B)) == + SADB_X_EXT_IV4B) { DPRINTF(("%s: 4-byte IV not supported with protocol\n", __func__)); return EINVAL; } - keylen = _KEYLEN(sav->key_enc); + /* subtract off the salt, RFC4106, 8.1 and RFC3686, 5.1 */ + keylen = _KEYLEN(sav->key_enc) - SAV_ISCTRORGCM(sav) * 4; if (txform->minkey > keylen || keylen > txform->maxkey) { DPRINTF(("%s: invalid key length %u, must be in the range " "[%u..%u] for algorithm %s\n", __func__, @@ -200,9 +205,10 @@ esp_init(struct secasvar *sav, struct xformsw *xsp) * the ESP header will be processed incorrectly. The * compromise is to force it to zero here. */ - sav->ivlen = (txform == &enc_xform_null ? 0 : txform->ivsize); - sav->iv = (caddr_t) malloc(sav->ivlen, M_XDATA, M_WAITOK); - key_randomfill(sav->iv, sav->ivlen); /*XXX*/ + if (SAV_ISCTRORGCM(sav)) + sav->ivlen = 8; /* RFC4106 3.1 and RFC3686 3.1 */ + else + sav->ivlen = (txform == &enc_xform_null ? 0 : txform->ivsize); /* * Setup AH-related state. @@ -224,15 +230,15 @@ esp_init(struct secasvar *sav, struct xformsw *xsp) */ if (sav->alg_enc == SADB_X_EALG_AESGCM16) { switch (keylen) { - case AES_128_HMAC_KEY_LEN: + case AES_128_GMAC_KEY_LEN: sav->alg_auth = SADB_X_AALG_AES128GMAC; sav->tdb_authalgxform = &auth_hash_nist_gmac_aes_128; break; - case AES_192_HMAC_KEY_LEN: + case AES_192_GMAC_KEY_LEN: sav->alg_auth = SADB_X_AALG_AES192GMAC; sav->tdb_authalgxform = &auth_hash_nist_gmac_aes_192; break; - case AES_256_HMAC_KEY_LEN: + case AES_256_GMAC_KEY_LEN: sav->alg_auth = SADB_X_AALG_AES256GMAC; sav->tdb_authalgxform = &auth_hash_nist_gmac_aes_256; break; @@ -244,19 +250,15 @@ esp_init(struct secasvar *sav, struct xformsw *xsp) } bzero(&cria, sizeof(cria)); cria.cri_alg = sav->tdb_authalgxform->type; - cria.cri_klen = _KEYBITS(sav->key_enc) + 4; cria.cri_key = sav->key_enc->key_data; + cria.cri_klen = _KEYBITS(sav->key_enc) - SAV_ISGCM(sav) * 32; } /* Initialize crypto session. */ - bzero(&crie, sizeof (crie)); + bzero(&crie, sizeof(crie)); crie.cri_alg = sav->tdb_encalgxform->type; - crie.cri_klen = _KEYBITS(sav->key_enc); crie.cri_key = sav->key_enc->key_data; - if (sav->alg_enc == SADB_X_EALG_AESGCM16) - arc4rand(crie.cri_iv, sav->ivlen, 0); - - /* XXX Rounds ? */ + crie.cri_klen = _KEYBITS(sav->key_enc) - SAV_ISCTRORGCM(sav) * 32; if (sav->tdb_authalgxform && sav->tdb_encalgxform) { /* init both auth & enc */ @@ -289,10 +291,6 @@ esp_zeroize(struct secasvar *sav) if (sav->key_enc) bzero(sav->key_enc->key_data, _KEYLEN(sav->key_enc)); - if (sav->iv) { - free(sav->iv, M_XDATA); - sav->iv = NULL; - } sav->tdb_encalgxform = NULL; sav->tdb_xform = NULL; return error; @@ -308,6 +306,7 @@ esp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) struct auth_hash *esph; struct enc_xform *espx; struct tdb_crypto *tc; + uint8_t *ivp; int plen, alen, hlen; struct newesp *esp; struct cryptodesc *crde; @@ -348,15 +347,13 @@ esp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) */ plen = m->m_pkthdr.len - (skip + hlen + alen); if ((plen & (espx->blocksize - 1)) || (plen <= 0)) { - if (!espx || sav->alg_enc != SADB_X_EALG_AESGCM16) { - DPRINTF(("%s: payload of %d octets not a multiple of %d octets," - " SA %s/%08lx\n", __func__, - plen, espx->blocksize, ipsec_address(&sav->sah->saidx.dst, - buf, sizeof(buf)), (u_long) ntohl(sav->spi))); - ESPSTAT_INC(esps_badilen); - m_freem(m); - return EINVAL; - } + DPRINTF(("%s: payload of %d octets not a multiple of %d octets," + " SA %s/%08lx\n", __func__, plen, espx->blocksize, + ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)), + (u_long)ntohl(sav->spi))); + ESPSTAT_INC(esps_badilen); + m_freem(m); + return EINVAL; } /* @@ -402,20 +399,13 @@ esp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) /* Authentication descriptor */ crda->crd_skip = skip; - if (espx && espx->type == CRYPTO_AES_NIST_GCM_16) - crda->crd_len = hlen - sav->ivlen; + if (SAV_ISGCM(sav)) + crda->crd_len = 8; /* RFC4106 5, SPI + SN */ else crda->crd_len = m->m_pkthdr.len - (skip + alen); crda->crd_inject = m->m_pkthdr.len - alen; crda->crd_alg = esph->type; - if (espx && (espx->type == CRYPTO_AES_NIST_GCM_16)) { - crda->crd_key = sav->key_enc->key_data; - crda->crd_klen = _KEYBITS(sav->key_enc); - } else { - crda->crd_key = sav->key_auth->key_data; - crda->crd_klen = _KEYBITS(sav->key_auth); - } /* Copy the authenticator */ m_copydata(m, m->m_pkthdr.len - alen, alen, @@ -450,13 +440,26 @@ esp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) crde->crd_len = m->m_pkthdr.len - (skip + hlen + alen); crde->crd_inject = skip + hlen - sav->ivlen; - crde->crd_alg = espx->type; - crde->crd_key = sav->key_enc->key_data; - crde->crd_klen = _KEYBITS(sav->key_enc); - if (espx && (espx->type == CRYPTO_AES_NIST_GCM_16)) + if (SAV_ISCTRORGCM(sav)) { + ivp = &crde->crd_iv[0]; + + /* GCM IV Format: RFC4106 4 */ + /* CTR IV Format: RFC3686 4 */ + /* Salt is last four bytes of key, RFC4106 8.1 */ + /* Nonce is last four bytes of key, RFC3686 5.1 */ + memcpy(ivp, sav->key_enc->key_data + + _KEYLEN(sav->key_enc) - 4, 4); + + if (SAV_ISCTR(sav)) { + /* Initial block counter is 1, RFC3686 4 */ + be32enc(&ivp[sav->ivlen + 4], 1); + } + + m_copydata(m, skip + hlen - sav->ivlen, sav->ivlen, &ivp[4]); crde->crd_flags |= CRD_F_IV_EXPLICIT; + } - /* XXX Rounds ? */ + crde->crd_alg = espx->type; return (crypto_dispatch(crp)); } @@ -662,6 +665,8 @@ esp_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp, char buf[INET6_ADDRSTRLEN]; struct enc_xform *espx; struct auth_hash *esph; + uint8_t *ivp; + uint64_t cntr; int hlen, rlen, padding, blks, alen, i, roff; struct mbuf *mo = (struct mbuf *) NULL; struct tdb_crypto *tc; @@ -687,10 +692,9 @@ esp_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp, rlen = m->m_pkthdr.len - skip; /* Raw payload length. */ /* - * NB: The null encoding transform has a blocksize of 4 - * so that headers are properly aligned. + * RFC4303 2.4 Requires 4 byte alignment. */ - blks = espx->ivsize; /* IV blocksize */ + blks = MAX(4, espx->blocksize); /* Cipher blocksize */ /* XXX clamp padding length a la KAME??? */ padding = ((blks - ((rlen + 2) % blks)) % blks) + 2; @@ -814,7 +818,7 @@ esp_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp, m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot); /* Get crypto descriptors. */ - crp = crypto_getreq(esph && espx ? 2 : 1); + crp = crypto_getreq(esph != NULL ? 2 : 1); if (crp == NULL) { DPRINTF(("%s: failed to acquire crypto descriptors\n", __func__)); @@ -823,29 +827,9 @@ esp_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp, goto bad; } - if (espx) { - crde = crp->crp_desc; - crda = crde->crd_next; - - /* Encryption descriptor. */ - crde->crd_skip = skip + hlen; - crde->crd_len = m->m_pkthdr.len - (skip + hlen + alen); - crde->crd_flags = CRD_F_ENCRYPT; - crde->crd_inject = skip + hlen - sav->ivlen; - - /* Encryption operation. */ - crde->crd_alg = espx->type; - crde->crd_key = sav->key_enc->key_data; - crde->crd_klen = _KEYBITS(sav->key_enc); - if (espx->type == CRYPTO_AES_NIST_GCM_16) - crde->crd_flags |= CRD_F_IV_EXPLICIT; - /* XXX Rounds ? */ - } else - crda = crp->crp_desc; - /* IPsec-specific opaque crypto info. */ tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto), - M_XDATA, M_NOWAIT|M_ZERO); + M_XDATA, M_NOWAIT|M_ZERO); if (tc == NULL) { crypto_freereq(crp); DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__)); @@ -854,6 +838,40 @@ esp_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp, goto bad; } + crde = crp->crp_desc; + crda = crde->crd_next; + + /* Encryption descriptor. */ + crde->crd_skip = skip + hlen; + crde->crd_len = m->m_pkthdr.len - (skip + hlen + alen); + crde->crd_flags = CRD_F_ENCRYPT; + crde->crd_inject = skip + hlen - sav->ivlen; + + /* Encryption operation. */ + crde->crd_alg = espx->type; + if (SAV_ISCTRORGCM(sav)) { + ivp = &crde->crd_iv[0]; + + /* GCM IV Format: RFC4106 4 */ + /* CTR IV Format: RFC3686 4 */ + /* Salt is last four bytes of key, RFC4106 8.1 */ + /* Nonce is last four bytes of key, RFC3686 5.1 */ + memcpy(ivp, sav->key_enc->key_data + + _KEYLEN(sav->key_enc) - 4, 4); + SECASVAR_LOCK(sav); + cntr = sav->cntr++; + SECASVAR_UNLOCK(sav); + be64enc(&ivp[4], cntr); + + if (SAV_ISCTR(sav)) { + /* Initial block counter is 1, RFC3686 4 */ + be32enc(&ivp[sav->ivlen + 4], 1); + } + + m_copyback(m, skip + hlen - sav->ivlen, sav->ivlen, &ivp[4]); + crde->crd_flags |= CRD_F_IV_EXPLICIT|CRD_F_IV_PRESENT; + } + /* Callback parameters */ tc->tc_isr = isr; KEY_ADDREFSA(sav); @@ -872,23 +890,13 @@ esp_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp, if (esph) { /* Authentication descriptor. */ + crda->crd_alg = esph->type; crda->crd_skip = skip; - if (espx && espx->type == CRYPTO_AES_NIST_GCM_16) - crda->crd_len = hlen - sav->ivlen; + if (SAV_ISGCM(sav)) + crda->crd_len = 8; /* RFC4106 5, SPI + SN */ else crda->crd_len = m->m_pkthdr.len - (skip + alen); crda->crd_inject = m->m_pkthdr.len - alen; - - /* Authentication operation. */ - crda->crd_alg = esph->type; - if (espx && espx->type == CRYPTO_AES_NIST_GCM_16) { - crda->crd_key = sav->key_enc->key_data; - crda->crd_klen = _KEYBITS(sav->key_enc); - } else { - crda->crd_key = sav->key_auth->key_data; - crda->crd_klen = _KEYBITS(sav->key_auth); - } - } return crypto_dispatch(crp); @@ -919,7 +927,8 @@ esp_output_cb(struct cryptop *crp) IPSEC_ASSERT(isr->sp != NULL, ("NULL isr->sp")); IPSECREQUEST_LOCK(isr); sav = tc->tc_sav; - /* With the isr lock released SA pointer can be updated. */ + + /* With the isr lock released, SA pointer may have changed. */ if (sav != isr->sav) { ESPSTAT_INC(esps_notdb); DPRINTF(("%s: SA gone during crypto (SA %s/%08lx proto %u)\n", |