/*
* ESP input processing, called (eventually) through the protocol switch.
*/
static int
esp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
{
char buf[128];
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;
struct cryptop *crp;
IPSEC_ASSERT(sav != NULL, ("null SA"));
IPSEC_ASSERT(sav->tdb_encalgxform != NULL, ("null encoding xform"));
/* Valid IP Packet length ? */
if ( (skip&3) || (m->m_pkthdr.len&3) ){
DPRINTF(("%s: misaligned packet, skip %u pkt len %u",
__func__, skip, m->m_pkthdr.len));
ESPSTAT_INC(esps_badilen);
m_freem(m);
return EINVAL;
}
/* XXX don't pullup, just copy header */
IP6_EXTHDR_GET(esp, struct newesp *, m, skip, sizeof (struct newesp));
esph = sav->tdb_authalgxform;
espx = sav->tdb_encalgxform;
/* Determine the ESP header and auth length */
if (sav->flags & SADB_X_EXT_OLD)
hlen = sizeof (struct esp) + sav->ivlen;
else
hlen = sizeof (struct newesp) + sav->ivlen;
alen = xform_ah_authsize(esph);
/*
* Verify payload length is multiple of encryption algorithm
* block size.
*
* NB: This works for the null algorithm because the blocksize
* is 4 and all packets must be 4-byte aligned regardless
* of the algorithm.
*/
plen = m->m_pkthdr.len - (skip + hlen + alen);
if ((plen & (espx->blocksize - 1)) || (plen <= 0)) {
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;
}
/*
* Check sequence number.
*/
if (esph != NULL && sav->replay != NULL &&
!ipsec_chkreplay(ntohl(esp->esp_seq), sav)) {
DPRINTF(("%s: packet replay check for %s\n", __func__,
ipsec_logsastr(sav, buf, sizeof(buf)))); /*XXX*/
ESPSTAT_INC(esps_replay);
m_freem(m);
return ENOBUFS; /*XXX*/
}
/* Update the counters */
ESPSTAT_ADD(esps_ibytes, m->m_pkthdr.len - (skip + hlen + alen));
/* Get crypto descriptors */
crp = crypto_getreq(esph && espx ? 2 : 1);
if (crp == NULL) {
DPRINTF(("%s: failed to acquire crypto descriptors\n",
__func__));
ESPSTAT_INC(esps_crypto);
m_freem(m);
return ENOBUFS;
}
/* Get IPsec-specific opaque pointer */
tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto) + alen,
M_XDATA, M_NOWAIT | M_ZERO);
if (tc == NULL) {
crypto_freereq(crp);
DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
ESPSTAT_INC(esps_crypto);
m_freem(m);
return ENOBUFS;
}
if (esph != NULL) {
struct cryptodesc *crda = crp->crp_desc;
IPSEC_ASSERT(crda != NULL, ("null ah crypto descriptor"));
/* Authentication descriptor */
crda->crd_skip = skip;
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;
/* Copy the authenticator */
m_copydata(m, m->m_pkthdr.len - alen, alen,
(caddr_t) (tc + 1));
/* Chain authentication request */
crde = crda->crd_next;
} else {
crde = crp->crp_desc;
}
/* Crypto operation descriptor */
crp->crp_ilen = m->m_pkthdr.len; /* Total input length */
crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
crp->crp_buf = (caddr_t) m;
crp->crp_callback = esp_input_cb;
crp->crp_sid = sav->tdb_cryptoid;
crp->crp_opaque = (caddr_t) tc;
/* These are passed as-is to the callback */
tc->tc_spi = sav->spi;
tc->tc_dst = sav->sah->saidx.dst;
tc->tc_proto = sav->sah->saidx.proto;
tc->tc_protoff = protoff;
tc->tc_skip = skip;
KEY_ADDREFSA(sav);
tc->tc_sav = sav;
/* Decryption descriptor */
IPSEC_ASSERT(crde != NULL, ("null esp crypto descriptor"));
crde->crd_skip = skip + hlen;
crde->crd_len = m->m_pkthdr.len - (skip + hlen + alen);
crde->crd_inject = skip + hlen - sav->ivlen;
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;
}
crde->crd_alg = espx->type;
return (crypto_dispatch(crp));
}
/*
* ESP input processing, called (eventually) through the protocol switch.
*/
static int
esp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
{
struct auth_hash *esph;
struct enc_xform *espx;
struct tdb_ident *tdbi;
struct tdb_crypto *tc;
int plen, alen, hlen;
struct m_tag *mtag;
struct newesp *esp;
struct cryptodesc *crde;
struct cryptop *crp;
IPSEC_ASSERT(sav != NULL, ("null SA"));
IPSEC_ASSERT(sav->tdb_encalgxform != NULL, ("null encoding xform"));
/* Valid IP Packet length ? */
if ( (skip&3) || (m->m_pkthdr.len&3) ){
DPRINTF(("%s: misaligned packet, skip %u pkt len %u",
__func__, skip, m->m_pkthdr.len));
ESPSTAT_INC(esps_badilen);
m_freem(m);
return EINVAL;
}
/* XXX don't pullup, just copy header */
IP6_EXTHDR_GET(esp, struct newesp *, m, skip, sizeof (struct newesp));
esph = sav->tdb_authalgxform;
espx = sav->tdb_encalgxform;
/* Determine the ESP header length */
if (sav->flags & SADB_X_EXT_OLD)
hlen = sizeof (struct esp) + sav->ivlen;
else
hlen = sizeof (struct newesp) + sav->ivlen;
/* Authenticator hash size */
if (esph != NULL) {
switch (esph->type) {
case CRYPTO_SHA2_256_HMAC:
case CRYPTO_SHA2_384_HMAC:
case CRYPTO_SHA2_512_HMAC:
alen = esph->hashsize/2;
break;
default:
alen = AH_HMAC_HASHLEN;
break;
}
}else
alen = 0;
/*
* Verify payload length is multiple of encryption algorithm
* block size.
*
* NB: This works for the null algorithm because the blocksize
* is 4 and all packets must be 4-byte aligned regardless
* of the algorithm.
*/
plen = m->m_pkthdr.len - (skip + hlen + alen);
if ((plen & (espx->blocksize - 1)) || (plen <= 0)) {
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),
(u_long) ntohl(sav->spi)));
ESPSTAT_INC(esps_badilen);
m_freem(m);
return EINVAL;
}
/*
* Check sequence number.
*/
if (esph && sav->replay && !ipsec_chkreplay(ntohl(esp->esp_seq), sav)) {
DPRINTF(("%s: packet replay check for %s\n", __func__,
ipsec_logsastr(sav))); /*XXX*/
ESPSTAT_INC(esps_replay);
m_freem(m);
return ENOBUFS; /*XXX*/
}
/* Update the counters */
ESPSTAT_ADD(esps_ibytes, m->m_pkthdr.len - (skip + hlen + alen));
/* Find out if we've already done crypto */
for (mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_CRYPTO_DONE, NULL);
mtag != NULL;
mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_CRYPTO_DONE, mtag)) {
tdbi = (struct tdb_ident *) (mtag + 1);
if (tdbi->proto == sav->sah->saidx.proto &&
tdbi->spi == sav->spi &&
!bcmp(&tdbi->dst, &sav->sah->saidx.dst,
sizeof(union sockaddr_union)))
break;
}
/* Get crypto descriptors */
crp = crypto_getreq(esph && espx ? 2 : 1);
if (crp == NULL) {
DPRINTF(("%s: failed to acquire crypto descriptors\n",
__func__));
ESPSTAT_INC(esps_crypto);
m_freem(m);
return ENOBUFS;
}
/* Get IPsec-specific opaque pointer */
if (esph == NULL || mtag != NULL)
tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto),
M_XDATA, M_NOWAIT|M_ZERO);
else
tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto) + alen,
M_XDATA, M_NOWAIT|M_ZERO);
if (tc == NULL) {
crypto_freereq(crp);
DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
ESPSTAT_INC(esps_crypto);
m_freem(m);
return ENOBUFS;
}
tc->tc_ptr = (caddr_t) mtag;
if (esph) {
struct cryptodesc *crda = crp->crp_desc;
IPSEC_ASSERT(crda != NULL, ("null ah crypto descriptor"));
/* Authentication descriptor */
crda->crd_skip = skip;
crda->crd_len = m->m_pkthdr.len - (skip + alen);
crda->crd_inject = m->m_pkthdr.len - alen;
crda->crd_alg = esph->type;
crda->crd_key = sav->key_auth->key_data;
crda->crd_klen = _KEYBITS(sav->key_auth);
/* Copy the authenticator */
if (mtag == NULL)
m_copydata(m, m->m_pkthdr.len - alen, alen,
(caddr_t) (tc + 1));
/* Chain authentication request */
crde = crda->crd_next;
} else {
crde = crp->crp_desc;
}
/* Crypto operation descriptor */
crp->crp_ilen = m->m_pkthdr.len; /* Total input length */
crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
crp->crp_buf = (caddr_t) m;
crp->crp_callback = esp_input_cb;
crp->crp_sid = sav->tdb_cryptoid;
crp->crp_opaque = (caddr_t) tc;
/* These are passed as-is to the callback */
tc->tc_spi = sav->spi;
tc->tc_dst = sav->sah->saidx.dst;
tc->tc_proto = sav->sah->saidx.proto;
tc->tc_protoff = protoff;
tc->tc_skip = skip;
KEY_ADDREFSA(sav);
tc->tc_sav = sav;
/* Decryption descriptor */
if (espx) {
IPSEC_ASSERT(crde != NULL, ("null esp crypto descriptor"));
crde->crd_skip = skip + hlen;
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);
/* XXX Rounds ? */
}
if (mtag == NULL)
return crypto_dispatch(crp);
else
return esp_input_cb(crp);
}
