/*
* IPsec input callback for INET protocols.
* This routine is called as the transform callback.
* Takes care of filtering and other sanity checks on
* the processed packet.
*/
int
ipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip,
int protoff)
{
char buf[INET6_ADDRSTRLEN];
struct ipsec_ctx_data ctx;
int prot, af, sproto, isr_prot;
struct ip *ip;
struct m_tag *mtag;
struct tdb_ident *tdbi;
struct secasindex *saidx;
int error;
#ifdef INET6
#ifdef notyet
char ip6buf[INET6_ADDRSTRLEN];
#endif
#endif
IPSEC_ASSERT(m != NULL, ("null mbuf"));
IPSEC_ASSERT(sav != NULL, ("null SA"));
IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
saidx = &sav->sah->saidx;
af = saidx->dst.sa.sa_family;
IPSEC_ASSERT(af == AF_INET, ("unexpected af %u", af));
sproto = saidx->proto;
IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
sproto == IPPROTO_IPCOMP,
("unexpected security protocol %u", sproto));
/* Sanity check */
if (m == NULL) {
DPRINTF(("%s: null mbuf", __func__));
IPSEC_ISTAT(sproto, badkcr);
KEY_FREESAV(&sav);
return EINVAL;
}
if (skip != 0) {
/*
* Fix IPv4 header
* XXXGL: do we need this entire block?
*/
if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) {
DPRINTF(("%s: processing failed for SA %s/%08lx\n",
__func__, ipsec_address(&sav->sah->saidx.dst,
buf, sizeof(buf)), (u_long) ntohl(sav->spi)));
IPSEC_ISTAT(sproto, hdrops);
error = ENOBUFS;
goto bad;
}
ip = mtod(m, struct ip *);
ip->ip_len = htons(m->m_pkthdr.len);
ip->ip_sum = 0;
ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
} else {
/*
* ESP input callback from the crypto driver.
*/
static int
esp_input_cb(struct cryptop *crp)
{
char buf[128];
u_int8_t lastthree[3], aalg[AH_HMAC_MAXHASHLEN];
int hlen, skip, protoff, error, alen;
struct mbuf *m;
struct cryptodesc *crd;
struct auth_hash *esph;
struct enc_xform *espx;
struct tdb_crypto *tc;
struct secasvar *sav;
struct secasindex *saidx;
caddr_t ptr;
crd = crp->crp_desc;
IPSEC_ASSERT(crd != NULL, ("null crypto descriptor!"));
tc = (struct tdb_crypto *) crp->crp_opaque;
IPSEC_ASSERT(tc != NULL, ("null opaque crypto data area!"));
skip = tc->tc_skip;
protoff = tc->tc_protoff;
m = (struct mbuf *) crp->crp_buf;
sav = tc->tc_sav;
IPSEC_ASSERT(sav != NULL, ("null SA!"));
saidx = &sav->sah->saidx;
IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
saidx->dst.sa.sa_family == AF_INET6,
("unexpected protocol family %u", saidx->dst.sa.sa_family));
esph = sav->tdb_authalgxform;
espx = sav->tdb_encalgxform;
/* Check for crypto errors */
if (crp->crp_etype) {
/* Reset the session ID */
if (sav->tdb_cryptoid != 0)
sav->tdb_cryptoid = crp->crp_sid;
if (crp->crp_etype == EAGAIN)
return (crypto_dispatch(crp));
ESPSTAT_INC(esps_noxform);
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
ESPSTAT_INC(esps_crypto);
DPRINTF(("%s: bogus returned buffer from crypto\n", __func__));
error = EINVAL;
goto bad;
}
ESPSTAT_INC(esps_hist[sav->alg_enc]);
/* If authentication was performed, check now. */
if (esph != NULL) {
alen = xform_ah_authsize(esph);
AHSTAT_INC(ahs_hist[sav->alg_auth]);
/* Copy the authenticator from the packet */
m_copydata(m, m->m_pkthdr.len - alen, alen, aalg);
ptr = (caddr_t) (tc + 1);
/* Verify authenticator */
if (timingsafe_bcmp(ptr, aalg, alen) != 0) {
DPRINTF(("%s: authentication hash mismatch for "
"packet in SA %s/%08lx\n", __func__,
ipsec_address(&saidx->dst, buf, sizeof(buf)),
(u_long) ntohl(sav->spi)));
ESPSTAT_INC(esps_badauth);
error = EACCES;
goto bad;
}
/* Remove trailing authenticator */
m_adj(m, -alen);
}
/* Release the crypto descriptors */
free(tc, M_XDATA), tc = NULL;
crypto_freereq(crp), crp = NULL;
/*
* Packet is now decrypted.
*/
m->m_flags |= M_DECRYPTED;
/*
* Update replay sequence number, if appropriate.
*/
if (sav->replay) {
u_int32_t seq;
m_copydata(m, skip + offsetof(struct newesp, esp_seq),
sizeof (seq), (caddr_t) &seq);
if (ipsec_updatereplay(ntohl(seq), sav)) {
DPRINTF(("%s: packet replay check for %s\n", __func__,
ipsec_logsastr(sav, buf, sizeof(buf))));
ESPSTAT_INC(esps_replay);
error = ENOBUFS;
goto bad;
}
}
/*
* ipsec_common_input gets called when an IPsec-protected packet
* is received by IPv4 or IPv6. Its job is to find the right SA
* and call the appropriate transform. The transform callback
* takes care of further processing (like ingress filtering).
*/
int
ipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto)
{
char buf[INET6_ADDRSTRLEN];
union sockaddr_union dst_address;
struct secasvar *sav;
u_int32_t spi;
int error;
#ifdef INET
#ifdef IPSEC_NAT_T
struct m_tag *tag;
#endif
#endif
IPSEC_ISTAT(sproto, input);
IPSEC_ASSERT(m != NULL, ("null packet"));
IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
sproto == IPPROTO_IPCOMP,
("unexpected security protocol %u", sproto));
if ((sproto == IPPROTO_ESP && !V_esp_enable) ||
(sproto == IPPROTO_AH && !V_ah_enable) ||
(sproto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
m_freem(m);
IPSEC_ISTAT(sproto, pdrops);
return EOPNOTSUPP;
}
if (m->m_pkthdr.len - skip < 2 * sizeof (u_int32_t)) {
m_freem(m);
IPSEC_ISTAT(sproto, hdrops);
DPRINTF(("%s: packet too small\n", __func__));
return EINVAL;
}
/* Retrieve the SPI from the relevant IPsec header */
if (sproto == IPPROTO_ESP)
m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi);
else if (sproto == IPPROTO_AH)
m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t),
(caddr_t) &spi);
else if (sproto == IPPROTO_IPCOMP) {
u_int16_t cpi;
m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t),
(caddr_t) &cpi);
spi = ntohl(htons(cpi));
}
/*
* Find the SA and (indirectly) call the appropriate
* kernel crypto routine. The resulting mbuf chain is a valid
* IP packet ready to go through input processing.
*/
bzero(&dst_address, sizeof (dst_address));
dst_address.sa.sa_family = af;
switch (af) {
#ifdef INET
case AF_INET:
dst_address.sin.sin_len = sizeof(struct sockaddr_in);
m_copydata(m, offsetof(struct ip, ip_dst),
sizeof(struct in_addr),
(caddr_t) &dst_address.sin.sin_addr);
#ifdef IPSEC_NAT_T
/* Find the source port for NAT-T; see udp*_espdecap. */
tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL);
if (tag != NULL)
dst_address.sin.sin_port = ((u_int16_t *)(tag + 1))[1];
#endif /* IPSEC_NAT_T */
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
dst_address.sin6.sin6_len = sizeof(struct sockaddr_in6);
m_copydata(m, offsetof(struct ip6_hdr, ip6_dst),
sizeof(struct in6_addr),
(caddr_t) &dst_address.sin6.sin6_addr);
/* We keep addresses in SADB without embedded scope id */
if (IN6_IS_SCOPE_LINKLOCAL(&dst_address.sin6.sin6_addr)) {
/* XXX: sa6_recoverscope() */
dst_address.sin6.sin6_scope_id =
ntohs(dst_address.sin6.sin6_addr.s6_addr16[1]);
dst_address.sin6.sin6_addr.s6_addr16[1] = 0;
}
break;
#endif /* INET6 */
default:
DPRINTF(("%s: unsupported protocol family %u\n", __func__, af));
m_freem(m);
IPSEC_ISTAT(sproto, nopf);
return EPFNOSUPPORT;
}
/* NB: only pass dst since key_allocsa follows RFC2401 */
sav = KEY_ALLOCSA(&dst_address, sproto, spi);
if (sav == NULL) {
DPRINTF(("%s: no key association found for SA %s/%08lx/%u\n",
__func__, ipsec_address(&dst_address, buf, sizeof(buf)),
(u_long) ntohl(spi), sproto));
IPSEC_ISTAT(sproto, notdb);
m_freem(m);
return ENOENT;
}
if (sav->tdb_xform == NULL) {
DPRINTF(("%s: attempted to use uninitialized SA %s/%08lx/%u\n",
__func__, ipsec_address(&dst_address, buf, sizeof(buf)),
(u_long) ntohl(spi), sproto));
IPSEC_ISTAT(sproto, noxform);
KEY_FREESAV(&sav);
m_freem(m);
return ENXIO;
}
/*
* Call appropriate transform and return -- callback takes care of
* everything else.
*/
error = (*sav->tdb_xform->xf_input)(m, sav, skip, protoff);
KEY_FREESAV(&sav);
return error;
}
/*
* 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);
}
/*
* 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 output routine, called by ipsec[46]_process_packet().
*/
static int
esp_output(
struct mbuf *m,
struct ipsecrequest *isr,
struct mbuf **mp,
int skip,
int protoff
)
{
struct enc_xform *espx;
struct auth_hash *esph;
int hlen, rlen, plen, padding, blks, alen, i, roff;
struct mbuf *mo = (struct mbuf *) NULL;
struct tdb_crypto *tc;
struct secasvar *sav;
struct secasindex *saidx;
unsigned char *pad;
u_int8_t prot;
int error, maxpacketsize;
struct cryptodesc *crde = NULL, *crda = NULL;
struct cryptop *crp;
SPLASSERT(net, "esp_output");
sav = isr->sav;
KASSERT(sav != NULL, ("esp_output: null SA"));
esph = sav->tdb_authalgxform;
espx = sav->tdb_encalgxform;
KASSERT(espx != NULL, ("esp_output: null encoding xform"));
if (sav->flags & SADB_X_EXT_OLD)
hlen = sizeof (struct esp) + sav->ivlen;
else
hlen = sizeof (struct newesp) + sav->ivlen;
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.
*/
blks = espx->blocksize; /* IV blocksize */
/* XXX clamp padding length a la KAME??? */
padding = ((blks - ((rlen + 2) % blks)) % blks) + 2;
plen = rlen + padding; /* Padded payload length. */
if (esph)
alen = AH_HMAC_HASHLEN;
else
alen = 0;
espstat.esps_output++;
saidx = &sav->sah->saidx;
/* Check for maximum packet size violations. */
switch (saidx->dst.sa.sa_family) {
#ifdef INET
case AF_INET:
maxpacketsize = IP_MAXPACKET;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
maxpacketsize = IPV6_MAXPACKET;
break;
#endif /* INET6 */
default:
DPRINTF(("esp_output: unknown/unsupported protocol "
"family %d, SA %s/%08lx\n",
saidx->dst.sa.sa_family, ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
espstat.esps_nopf++;
error = EPFNOSUPPORT;
goto bad;
}
if (skip + hlen + rlen + padding + alen > maxpacketsize) {
DPRINTF(("esp_output: packet in SA %s/%08lx got too big "
"(len %u, max len %u)\n",
ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi),
skip + hlen + rlen + padding + alen, maxpacketsize));
espstat.esps_toobig++;
error = EMSGSIZE;
goto bad;
}
/* Update the counters. */
espstat.esps_obytes += m->m_pkthdr.len - skip;
m = m_clone(m);
if (m == NULL) {
DPRINTF(("esp_output: cannot clone mbuf chain, SA %s/%08lx\n",
ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi)));
espstat.esps_hdrops++;
error = ENOBUFS;
goto bad;
}
/* Inject ESP header. */
mo = m_makespace(m, skip, hlen, &roff);
if (mo == NULL) {
DPRINTF(("esp_output: failed to inject %u byte ESP hdr for SA "
"%s/%08lx\n",
hlen, ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
espstat.esps_hdrops++; /* XXX diffs from openbsd */
error = ENOBUFS;
goto bad;
}
/* Initialize ESP header. */
bcopy((caddr_t) &sav->spi, mtod(mo, caddr_t) + roff, sizeof(u_int32_t));
if (sav->replay) {
u_int32_t replay = htonl(++(sav->replay->count));
bcopy((caddr_t) &replay,
mtod(mo, caddr_t) + roff + sizeof(u_int32_t),
sizeof(u_int32_t));
}
/*
* Add padding -- better to do it ourselves than use the crypto engine,
* although if/when we support compression, we'd have to do that.
*/
pad = (u_char *) m_pad(m, padding + alen);
if (pad == NULL) {
DPRINTF(("esp_output: m_pad failed for SA %s/%08lx\n",
ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi)));
m = NULL; /* NB: free'd by m_pad */
error = ENOBUFS;
goto bad;
}
/*
* Add padding: random, zero, or self-describing.
* XXX catch unexpected setting
*/
switch (sav->flags & SADB_X_EXT_PMASK) {
case SADB_X_EXT_PRAND:
(void) read_random(pad, padding - 2);
break;
case SADB_X_EXT_PZERO:
bzero(pad, padding - 2);
break;
case SADB_X_EXT_PSEQ:
for (i = 0; i < padding - 2; i++)
pad[i] = i+1;
break;
}
/* Fix padding length and Next Protocol in padding itself. */
pad[padding - 2] = padding - 2;
m_copydata(m, protoff, sizeof(u_int8_t), pad + padding - 1);
/* Fix Next Protocol in IPv4/IPv6 header. */
prot = IPPROTO_ESP;
m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot);
/* Get crypto descriptors. */
crp = crypto_getreq(esph && espx ? 2 : 1);
if (crp == NULL) {
DPRINTF(("esp_output: failed to acquire crypto descriptors\n"));
espstat.esps_crypto++;
error = ENOBUFS;
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 = _KEYBUF(sav->key_enc);
crde->crd_klen = _KEYBITS(sav->key_enc);
/* 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);
if (tc == NULL) {
crypto_freereq(crp);
DPRINTF(("esp_output: failed to allocate tdb_crypto\n"));
espstat.esps_crypto++;
error = ENOBUFS;
goto bad;
}
/* Callback parameters */
tc->tc_isr = isr;
tc->tc_spi = sav->spi;
tc->tc_dst = saidx->dst;
tc->tc_proto = saidx->proto;
/* Crypto operation descriptor. */
crp->crp_ilen = m->m_pkthdr.len; /* Total input length. */
crp->crp_flags = CRYPTO_F_IMBUF;
crp->crp_buf = (caddr_t) m;
crp->crp_callback = esp_output_cb;
crp->crp_opaque = (caddr_t) tc;
crp->crp_sid = sav->tdb_cryptoid;
if (esph) {
/* Authentication descriptor. */
crda->crd_skip = skip;
crda->crd_len = m->m_pkthdr.len - (skip + alen);
crda->crd_inject = m->m_pkthdr.len - alen;
/* Authentication operation. */
crda->crd_alg = esph->type;
crda->crd_key = _KEYBUF(sav->key_auth);
crda->crd_klen = _KEYBITS(sav->key_auth);
}
return crypto_dispatch(crp);
bad:
if (m)
m_freem(m);
return (error);
}
/*
* ESP output callback from the crypto driver.
*/
static int
esp_output_cb(struct cryptop *crp)
{
struct tdb_crypto *tc;
struct ipsecrequest *isr;
struct secasvar *sav;
struct mbuf *m;
int s, err, error;
tc = (struct tdb_crypto *) crp->crp_opaque;
KASSERT(tc != NULL, ("esp_output_cb: null opaque data area!"));
m = (struct mbuf *) crp->crp_buf;
s = splnet();
isr = tc->tc_isr;
sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
if (sav == NULL) {
espstat.esps_notdb++;
DPRINTF(("esp_output_cb: SA expired while in crypto "
"(SA %s/%08lx proto %u)\n", ipsec_address(&tc->tc_dst),
(u_long) ntohl(tc->tc_spi), tc->tc_proto));
error = ENOBUFS; /*XXX*/
goto bad;
}
KASSERT(isr->sav == sav,
("esp_output_cb: SA changed was %p now %p\n", isr->sav, sav));
/* Check for crypto errors. */
if (crp->crp_etype) {
/* Reset session ID. */
if (sav->tdb_cryptoid != 0)
sav->tdb_cryptoid = crp->crp_sid;
if (crp->crp_etype == EAGAIN) {
KEY_FREESAV(&sav);
splx(s);
return crypto_dispatch(crp);
}
espstat.esps_noxform++;
DPRINTF(("esp_output_cb: crypto error %d\n", crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
espstat.esps_crypto++;
DPRINTF(("esp_output_cb: bogus returned buffer from crypto\n"));
error = EINVAL;
goto bad;
}
espstat.esps_hist[sav->alg_enc]++;
if (sav->tdb_authalgxform != NULL)
ahstat.ahs_hist[sav->alg_auth]++;
/* Release crypto descriptors. */
free(tc, M_XDATA);
crypto_freereq(crp);
/* NB: m is reclaimed by ipsec_process_done. */
err = ipsec_process_done(m, isr);
KEY_FREESAV(&sav);
splx(s);
return err;
bad:
if (sav)
KEY_FREESAV(&sav);
splx(s);
if (m)
m_freem(m);
free(tc, M_XDATA);
crypto_freereq(crp);
return error;
}
/*
* ESP input callback from the crypto driver.
*/
static int
esp_input_cb(struct cryptop *crp)
{
u_int8_t lastthree[3], aalg[AH_HMAC_HASHLEN];
int s, hlen, skip, protoff, error;
struct mbuf *m;
struct cryptodesc *crd;
struct auth_hash *esph;
struct enc_xform *espx;
struct tdb_crypto *tc;
struct m_tag *mtag;
struct secasvar *sav;
struct secasindex *saidx;
caddr_t ptr;
crd = crp->crp_desc;
KASSERT(crd != NULL, ("esp_input_cb: null crypto descriptor!"));
tc = (struct tdb_crypto *) crp->crp_opaque;
KASSERT(tc != NULL, ("esp_input_cb: null opaque crypto data area!"));
skip = tc->tc_skip;
protoff = tc->tc_protoff;
mtag = (struct m_tag *) tc->tc_ptr;
m = (struct mbuf *) crp->crp_buf;
s = splnet();
sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
if (sav == NULL) {
espstat.esps_notdb++;
DPRINTF(("esp_input_cb: SA expired while in crypto "
"(SA %s/%08lx proto %u)\n", ipsec_address(&tc->tc_dst),
(u_long) ntohl(tc->tc_spi), tc->tc_proto));
error = ENOBUFS; /*XXX*/
goto bad;
}
saidx = &sav->sah->saidx;
KASSERT(saidx->dst.sa.sa_family == AF_INET ||
saidx->dst.sa.sa_family == AF_INET6,
("ah_input_cb: unexpected protocol family %u",
saidx->dst.sa.sa_family));
esph = sav->tdb_authalgxform;
espx = sav->tdb_encalgxform;
/* Check for crypto errors */
if (crp->crp_etype) {
/* Reset the session ID */
if (sav->tdb_cryptoid != 0)
sav->tdb_cryptoid = crp->crp_sid;
if (crp->crp_etype == EAGAIN) {
KEY_FREESAV(&sav);
splx(s);
return crypto_dispatch(crp);
}
espstat.esps_noxform++;
DPRINTF(("esp_input_cb: crypto error %d\n", crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
espstat.esps_crypto++;
DPRINTF(("esp_input_cb: bogus returned buffer from crypto\n"));
error = EINVAL;
goto bad;
}
espstat.esps_hist[sav->alg_enc]++;
/* If authentication was performed, check now. */
if (esph != NULL) {
/*
* If we have a tag, it means an IPsec-aware NIC did
* the verification for us. Otherwise we need to
* check the authentication calculation.
*/
ahstat.ahs_hist[sav->alg_auth]++;
if (mtag == NULL) {
/* Copy the authenticator from the packet */
m_copydata(m, m->m_pkthdr.len - esph->authsize,
esph->authsize, aalg);
ptr = (caddr_t) (tc + 1);
/* Verify authenticator */
if (bcmp(ptr, aalg, esph->authsize) != 0) {
DPRINTF(("esp_input_cb: "
"authentication hash mismatch for packet in SA %s/%08lx\n",
ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
espstat.esps_badauth++;
error = EACCES;
goto bad;
}
}
/* Remove trailing authenticator */
m_adj(m, -(esph->authsize));
}
/* Release the crypto descriptors */
free(tc, M_XDATA), tc = NULL;
crypto_freereq(crp), crp = NULL;
/*
* Packet is now decrypted.
*/
m->m_flags |= M_DECRYPTED;
/* 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;
/* Remove the ESP header and IV from the mbuf. */
error = m_striphdr(m, skip, hlen);
if (error) {
espstat.esps_hdrops++;
DPRINTF(("esp_input_cb: bad mbuf chain, SA %s/%08lx\n",
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
goto bad;
}
/* Save the last three bytes of decrypted data */
m_copydata(m, m->m_pkthdr.len - 3, 3, lastthree);
/* Verify pad length */
if (lastthree[1] + 2 > m->m_pkthdr.len - skip) {
espstat.esps_badilen++;
DPRINTF(("esp_input_cb: invalid padding length %d "
"for %u byte packet in SA %s/%08lx\n",
lastthree[1], m->m_pkthdr.len - skip,
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
error = EINVAL;
goto bad;
}
/* Verify correct decryption by checking the last padding bytes */
if ((sav->flags & SADB_X_EXT_PMASK) != SADB_X_EXT_PRAND) {
if (lastthree[1] != lastthree[0] && lastthree[1] != 0) {
espstat.esps_badenc++;
DPRINTF(("esp_input_cb: decryption failed "
"for packet in SA %s/%08lx\n",
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
DPRINTF(("esp_input_cb: %x %x\n", lastthree[0], lastthree[1]));
error = EINVAL;
goto bad;
}
}
/* Trim the mbuf chain to remove trailing authenticator and padding */
m_adj(m, -(lastthree[1] + 2));
/* Restore the Next Protocol field */
m_copyback(m, protoff, sizeof (u_int8_t), lastthree + 2);
IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag);
KEY_FREESAV(&sav);
splx(s);
return error;
bad:
if (sav)
KEY_FREESAV(&sav);
splx(s);
if (m != NULL)
m_freem(m);
if (tc != NULL)
free(tc, M_XDATA);
if (crp != NULL)
crypto_freereq(crp);
return error;
}
/*
* ESP input callback from the crypto driver.
*/
static int
esp_input_cb(struct cryptop *crp)
{
u_int8_t lastthree[3], aalg[AH_HMAC_MAXHASHLEN];
int hlen, skip, protoff, error, alen;
struct mbuf *m;
struct cryptodesc *crd;
struct auth_hash *esph;
struct enc_xform *espx;
struct tdb_crypto *tc;
struct m_tag *mtag;
struct secasvar *sav;
struct secasindex *saidx;
caddr_t ptr;
crd = crp->crp_desc;
IPSEC_ASSERT(crd != NULL, ("null crypto descriptor!"));
tc = (struct tdb_crypto *) crp->crp_opaque;
IPSEC_ASSERT(tc != NULL, ("null opaque crypto data area!"));
skip = tc->tc_skip;
protoff = tc->tc_protoff;
mtag = (struct m_tag *) tc->tc_ptr;
m = (struct mbuf *) crp->crp_buf;
sav = tc->tc_sav;
IPSEC_ASSERT(sav != NULL, ("null SA!"));
saidx = &sav->sah->saidx;
IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
saidx->dst.sa.sa_family == AF_INET6,
("unexpected protocol family %u", saidx->dst.sa.sa_family));
esph = sav->tdb_authalgxform;
espx = sav->tdb_encalgxform;
/* Check for crypto errors */
if (crp->crp_etype) {
/* Reset the session ID */
if (sav->tdb_cryptoid != 0)
sav->tdb_cryptoid = crp->crp_sid;
if (crp->crp_etype == EAGAIN)
return (crypto_dispatch(crp));
V_espstat.esps_noxform++;
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
V_espstat.esps_crypto++;
DPRINTF(("%s: bogus returned buffer from crypto\n", __func__));
error = EINVAL;
goto bad;
}
V_espstat.esps_hist[sav->alg_enc]++;
/* If authentication was performed, check now. */
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;
}
/*
* If we have a tag, it means an IPsec-aware NIC did
* the verification for us. Otherwise we need to
* check the authentication calculation.
*/
V_ahstat.ahs_hist[sav->alg_auth]++;
if (mtag == NULL) {
/* Copy the authenticator from the packet */
m_copydata(m, m->m_pkthdr.len - alen,
alen, aalg);
ptr = (caddr_t) (tc + 1);
/* Verify authenticator */
if (bcmp(ptr, aalg, alen) != 0) {
DPRINTF(("%s: "
"authentication hash mismatch for packet in SA %s/%08lx\n",
__func__,
ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
V_espstat.esps_badauth++;
error = EACCES;
goto bad;
}
}
/* Remove trailing authenticator */
m_adj(m, -alen);
}
/* Release the crypto descriptors */
free(tc, M_XDATA), tc = NULL;
crypto_freereq(crp), crp = NULL;
/*
* Packet is now decrypted.
*/
m->m_flags |= M_DECRYPTED;
/*
* Update replay sequence number, if appropriate.
*/
if (sav->replay) {
u_int32_t seq;
m_copydata(m, skip + offsetof(struct newesp, esp_seq),
sizeof (seq), (caddr_t) &seq);
if (ipsec_updatereplay(ntohl(seq), sav)) {
DPRINTF(("%s: packet replay check for %s\n", __func__,
ipsec_logsastr(sav)));
V_espstat.esps_replay++;
error = ENOBUFS;
goto bad;
}
}
/*
* ESP input callback from the crypto driver.
*/
static int
esp_input_cb(struct cryptop *crp)
{
u_int8_t lastthree[3], aalg[AH_ALEN_MAX];
int s, hlen, skip, protoff, error;
struct mbuf *m;
struct cryptodesc *crd;
const struct auth_hash *esph;
const struct enc_xform *espx;
struct tdb_crypto *tc;
struct m_tag *mtag;
struct secasvar *sav;
struct secasindex *saidx;
void *ptr;
u_int16_t dport;
u_int16_t sport;
crd = crp->crp_desc;
IPSEC_ASSERT(crd != NULL, ("esp_input_cb: null crypto descriptor!"));
tc = (struct tdb_crypto *) crp->crp_opaque;
IPSEC_ASSERT(tc != NULL, ("esp_input_cb: null opaque crypto data area!"));
skip = tc->tc_skip;
protoff = tc->tc_protoff;
mtag = (struct m_tag *) tc->tc_ptr;
m = (struct mbuf *) crp->crp_buf;
/* find the source port for NAT-T */
nat_t_ports_get(m, &dport, &sport);
s = splsoftnet();
mutex_enter(softnet_lock);
sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, sport, dport);
if (sav == NULL) {
ESP_STATINC(ESP_STAT_NOTDB);
DPRINTF(("esp_input_cb: SA expired while in crypto "
"(SA %s/%08lx proto %u)\n", ipsec_address(&tc->tc_dst),
(u_long) ntohl(tc->tc_spi), tc->tc_proto));
error = ENOBUFS; /*XXX*/
goto bad;
}
saidx = &sav->sah->saidx;
IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
saidx->dst.sa.sa_family == AF_INET6,
("esp_input_cb: unexpected protocol family %u",
saidx->dst.sa.sa_family));
esph = sav->tdb_authalgxform;
espx = sav->tdb_encalgxform;
/* Check for crypto errors */
if (crp->crp_etype) {
/* Reset the session ID */
if (sav->tdb_cryptoid != 0)
sav->tdb_cryptoid = crp->crp_sid;
if (crp->crp_etype == EAGAIN) {
KEY_FREESAV(&sav);
mutex_exit(softnet_lock);
splx(s);
return crypto_dispatch(crp);
}
ESP_STATINC(ESP_STAT_NOXFORM);
DPRINTF(("esp_input_cb: crypto error %d\n", crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
ESP_STATINC(ESP_STAT_CRYPTO);
DPRINTF(("esp_input_cb: bogus returned buffer from crypto\n"));
error = EINVAL;
goto bad;
}
ESP_STATINC(ESP_STAT_HIST + sav->alg_enc);
/* If authentication was performed, check now. */
if (esph != NULL) {
/*
* If we have a tag, it means an IPsec-aware NIC did
* the verification for us. Otherwise we need to
* check the authentication calculation.
*/
AH_STATINC(AH_STAT_HIST + sav->alg_auth);
if (mtag == NULL) {
/* Copy the authenticator from the packet */
m_copydata(m, m->m_pkthdr.len - esph->authsize,
esph->authsize, aalg);
ptr = (tc + 1);
/* Verify authenticator */
if (!consttime_memequal(ptr, aalg, esph->authsize)) {
DPRINTF(("esp_input_cb: "
"authentication hash mismatch for packet in SA %s/%08lx\n",
ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
ESP_STATINC(ESP_STAT_BADAUTH);
error = EACCES;
goto bad;
}
}
/* Remove trailing authenticator */
m_adj(m, -(esph->authsize));
}
/* Release the crypto descriptors */
free(tc, M_XDATA), tc = NULL;
crypto_freereq(crp), crp = NULL;
/*
* Packet is now decrypted.
*/
m->m_flags |= M_DECRYPTED;
/*
* Update replay sequence number, if appropriate.
*/
if (sav->replay) {
u_int32_t seq;
m_copydata(m, skip + offsetof(struct newesp, esp_seq),
sizeof (seq), &seq);
if (ipsec_updatereplay(ntohl(seq), sav)) {
DPRINTF(("%s: packet replay check for %s\n", __func__,
ipsec_logsastr(sav)));
ESP_STATINC(ESP_STAT_REPLAY);
error = ENOBUFS;
goto bad;
}
}
/*
* ESP input processing, called (eventually) through the protocol switch.
*/
static int
esp_input(struct mbuf *m, const struct secasvar *sav, int skip, int protoff)
{
const struct auth_hash *esph;
const struct enc_xform *espx;
struct tdb_ident *tdbi;
struct tdb_crypto *tc;
int plen, alen, hlen, error;
struct m_tag *mtag;
struct newesp *esp;
struct cryptodesc *crde;
struct cryptop *crp;
IPSEC_SPLASSERT_SOFTNET("esp_input");
IPSEC_ASSERT(sav != NULL, ("esp_input: null SA"));
IPSEC_ASSERT(sav->tdb_encalgxform != NULL,
("esp_input: null encoding xform"));
IPSEC_ASSERT((skip&3) == 0 && (m->m_pkthdr.len&3) == 0,
("esp_input: misaligned packet, skip %u pkt len %u",
skip, m->m_pkthdr.len));
/* 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 */
alen = esph ? esph->authsize : 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(("esp_input: "
"payload of %d octets not a multiple of %d octets,"
" SA %s/%08lx\n",
plen, espx->blocksize,
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
ESP_STATINC(ESP_STAT_BADILEN);
m_freem(m);
return EINVAL;
}
/*
* Check sequence number.
*/
if (esph && sav->replay && !ipsec_chkreplay(ntohl(esp->esp_seq), sav)) {
DPRINTF(("esp_input: packet replay check for %s\n",
ipsec_logsastr(sav))); /*XXX*/
ESP_STATINC(ESP_STAT_REPLAY);
m_freem(m);
return ENOBUFS; /*XXX*/
}
/* Update the counters */
ESP_STATADD(ESP_STAT_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 &&
!memcmp(&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(("esp_input: failed to acquire crypto descriptors\n"));
ESP_STATINC(ESP_STAT_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(("esp_input: failed to allocate tdb_crypto\n"));
ESP_STATINC(ESP_STAT_CRYPTO);
m_freem(m);
return ENOBUFS;
}
error = m_makewritable(&m, 0, m->m_pkthdr.len, M_NOWAIT);
if (error) {
m_freem(m);
free(tc, M_XDATA);
crypto_freereq(crp);
DPRINTF(("esp_input: m_makewritable failed\n"));
ESP_STATINC(ESP_STAT_CRYPTO);
return error;
}
tc->tc_ptr = mtag;
if (esph) {
struct cryptodesc *crda = crp->crp_desc;
IPSEC_ASSERT(crda != NULL, ("esp_input: null ah crypto descriptor"));
/* Authentication descriptor */
crda->crd_skip = skip;
if (espx && espx->type == CRYPTO_AES_GCM_16)
crda->crd_len = hlen - sav->ivlen;
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_GCM_16 ||
espx->type == CRYPTO_AES_GMAC)) {
crda->crd_key = _KEYBUF(sav->key_enc);
crda->crd_klen = _KEYBITS(sav->key_enc);
} else {
crda->crd_key = _KEYBUF(sav->key_auth);
crda->crd_klen = _KEYBITS(sav->key_auth);
}
/* Copy the authenticator */
if (mtag == NULL)
m_copydata(m, m->m_pkthdr.len - alen, alen,
(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;
crp->crp_buf = m;
crp->crp_callback = esp_input_cb;
crp->crp_sid = sav->tdb_cryptoid;
crp->crp_opaque = 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;
/* Decryption descriptor */
if (espx) {
IPSEC_ASSERT(crde != NULL, ("esp_input: null esp crypto descriptor"));
crde->crd_skip = skip + hlen;
if (espx->type == CRYPTO_AES_GMAC)
crde->crd_len = 0;
else
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 = _KEYBUF(sav->key_enc);
crde->crd_klen = _KEYBITS(sav->key_enc);
/* XXX Rounds ? */
}
if (mtag == NULL)
return crypto_dispatch(crp);
else
return esp_input_cb(crp);
}
/*
* ESP input callback from the crypto driver.
*/
static int
esp_input_cb(struct cryptop *crp)
{
IPSEC_DEBUG_DECLARE(char buf[128]);
u_int8_t lastthree[3], aalg[AH_HMAC_MAXHASHLEN];
const struct auth_hash *esph;
const struct enc_xform *espx;
struct mbuf *m;
struct cryptodesc *crd;
struct xform_data *xd;
struct secasvar *sav;
struct secasindex *saidx;
caddr_t ptr;
uint64_t cryptoid;
int hlen, skip, protoff, error, alen;
crd = crp->crp_desc;
IPSEC_ASSERT(crd != NULL, ("null crypto descriptor!"));
m = (struct mbuf *) crp->crp_buf;
xd = (struct xform_data *) crp->crp_opaque;
sav = xd->sav;
skip = xd->skip;
protoff = xd->protoff;
cryptoid = xd->cryptoid;
saidx = &sav->sah->saidx;
esph = sav->tdb_authalgxform;
espx = sav->tdb_encalgxform;
/* Check for crypto errors */
if (crp->crp_etype) {
if (crp->crp_etype == EAGAIN) {
/* Reset the session ID */
if (ipsec_updateid(sav, &crp->crp_sid, &cryptoid) != 0)
crypto_freesession(cryptoid);
xd->cryptoid = crp->crp_sid;
return (crypto_dispatch(crp));
}
ESPSTAT_INC(esps_noxform);
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
ESPSTAT_INC(esps_crypto);
DPRINTF(("%s: bogus returned buffer from crypto\n", __func__));
error = EINVAL;
goto bad;
}
ESPSTAT_INC(esps_hist[sav->alg_enc]);
/* If authentication was performed, check now. */
if (esph != NULL) {
alen = xform_ah_authsize(esph);
AHSTAT_INC(ahs_hist[sav->alg_auth]);
/* Copy the authenticator from the packet */
m_copydata(m, m->m_pkthdr.len - alen, alen, aalg);
ptr = (caddr_t) (xd + 1);
/* Verify authenticator */
if (timingsafe_bcmp(ptr, aalg, alen) != 0) {
DPRINTF(("%s: authentication hash mismatch for "
"packet in SA %s/%08lx\n", __func__,
ipsec_address(&saidx->dst, buf, sizeof(buf)),
(u_long) ntohl(sav->spi)));
ESPSTAT_INC(esps_badauth);
error = EACCES;
goto bad;
}
m->m_flags |= M_AUTHIPDGM;
/* Remove trailing authenticator */
m_adj(m, -alen);
}
/* Release the crypto descriptors */
free(xd, M_XDATA), xd = NULL;
crypto_freereq(crp), crp = NULL;
/*
* Packet is now decrypted.
*/
m->m_flags |= M_DECRYPTED;
/*
* Update replay sequence number, if appropriate.
*/
if (sav->replay) {
u_int32_t seq;
m_copydata(m, skip + offsetof(struct newesp, esp_seq),
sizeof (seq), (caddr_t) &seq);
SECASVAR_LOCK(sav);
if (ipsec_updatereplay(ntohl(seq), sav)) {
SECASVAR_UNLOCK(sav);
DPRINTF(("%s: packet replay check for %s\n", __func__,
ipsec_sa2str(sav, buf, sizeof(buf))));
ESPSTAT_INC(esps_replay);
error = EACCES;
goto bad;
}
SECASVAR_UNLOCK(sav);
}
