/* Generate and match a NAT-D hash against the NAT-D payload (pl.) data. */
static int
nat_t_match_nat_d_payload(struct message *msg, struct sockaddr *sa)
{
struct payload *p;
u_int8_t *hbuf;
size_t hbuflen;
int found = 0;
/*
* If there are no NAT-D payloads in the message, return "found"
* as this will avoid NAT-T (see nat_t_exchange_check_nat_d()).
*/
if ((p = payload_first(msg, ISAKMP_PAYLOAD_NAT_D_DRAFT)) == NULL &&
(p = payload_first(msg, ISAKMP_PAYLOAD_NAT_D)) == NULL)
return 1;
hbuf = nat_t_generate_nat_d_hash(msg, sa, &hbuflen);
if (!hbuf)
return 0;
for (; p; p = TAILQ_NEXT(p, link)) {
if (GET_ISAKMP_GEN_LENGTH (p->p) !=
hbuflen + ISAKMP_NAT_D_DATA_OFF)
continue;
if (memcmp(p->p + ISAKMP_NAT_D_DATA_OFF, hbuf, hbuflen) == 0) {
found++;
break;
}
}
free(hbuf);
return found;
}
/*
* Check an incoming message for NAT-T capability markers.
*/
void
nat_t_check_vendor_payload(struct message *msg, struct payload *p)
{
u_int8_t *pbuf = p->p;
size_t vlen;
int i;
if (disable_nat_t)
return;
vlen = GET_ISAKMP_GEN_LENGTH(pbuf) - ISAKMP_GEN_SZ;
for (i = 0; i < NUMNATTCAP; i++) {
if (vlen != isakmp_nat_t_cap[i].hashsize) {
continue;
}
if (memcmp(isakmp_nat_t_cap[i].hash, pbuf + ISAKMP_GEN_SZ,
vlen) == 0) {
/* This peer is NAT-T capable. */
msg->exchange->flags |= EXCHANGE_FLAG_NAT_T_CAP_PEER;
msg->exchange->flags |= isakmp_nat_t_cap[i].flags;
LOG_DBG((LOG_EXCHANGE, 10,
"nat_t_check_vendor_payload: "
"NAT-T capable peer detected"));
p->flags |= PL_MARK;
}
}
return;
}
/*
* Accept a set of transforms offered by the initiator and chose one we can
* handle.
*/
int
ike_phase_1_responder_recv_SA (struct message *msg)
{
struct exchange *exchange = msg->exchange;
struct sa *sa = TAILQ_FIRST (&exchange->sa_list);
struct ipsec_sa *isa = sa->data;
struct payload *sa_p = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_SA]);
struct payload *prop = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_PROPOSAL]);
struct ipsec_exch *ie = exchange->data;
/* Mark the SA as handled. */
sa_p->flags |= PL_MARK;
/* IKE requires that only one SA with only one proposal exists. */
if (TAILQ_NEXT (sa_p, link) || TAILQ_NEXT (prop, link))
{
log_print ("ike_phase_1_responder_recv_SA: "
"multiple SA or proposal payloads in phase 1");
/* XXX Is there a better notification type? */
message_drop (msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
return -1;
}
/* Chose a transform from the SA. */
if (message_negotiate_sa (msg, ike_phase_1_validate_prop)
|| !TAILQ_FIRST (&sa->protos))
return -1;
/* XXX Move into message_negotiate_sa? */
ipsec_decode_transform (msg, sa, TAILQ_FIRST (&sa->protos),
TAILQ_FIRST (&sa->protos)->chosen->p);
ie->group = group_get (isa->group_desc);
/*
* Check that the mandatory attributes: encryption, hash, authentication
* method and Diffie-Hellman group description, has been supplied.
*/
if (!exchange->crypto || !ie->hash || !ie->ike_auth || !ie->group)
{
message_drop (msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
return -1;
}
/* Save the body for later hash computation. */
ie->sa_i_b_len = GET_ISAKMP_GEN_LENGTH (sa_p->p) - ISAKMP_GEN_SZ;
ie->sa_i_b = malloc (ie->sa_i_b_len);
if (!ie->sa_i_b)
{
/* XXX How to notify peer? */
log_error ("ike_phase_1_responder_recv_SA: malloc (%lu) failed",
(unsigned long)ie->sa_i_b_len);
return -1;
}
memcpy (ie->sa_i_b, sa_p->p + ISAKMP_GEN_SZ, ie->sa_i_b_len);
return 0;
}
int
cfg_verify_hash(struct message *msg)
{
struct payload *hashp = payload_first(msg, ISAKMP_PAYLOAD_HASH);
struct ipsec_sa *isa = msg->isakmp_sa->data;
struct prf *prf;
u_int8_t *hash, *comp_hash;
size_t hash_len;
if (!hashp) {
log_print("cfg_verify_hash: phase 2 message missing HASH");
message_drop(msg, ISAKMP_NOTIFY_INVALID_HASH_INFORMATION,
0, 1, 0);
return -1;
}
hash = hashp->p;
hash_len = GET_ISAKMP_GEN_LENGTH(hash);
comp_hash = malloc(hash_len - ISAKMP_GEN_SZ);
if (!comp_hash) {
log_error("cfg_verify_hash: malloc (%lu) failed",
(unsigned long)hash_len - ISAKMP_GEN_SZ);
return -1;
}
/* Verify hash. */
prf = prf_alloc(isa->prf_type, isa->hash, isa->skeyid_a,
isa->skeyid_len);
if (!prf) {
free(comp_hash);
return -1;
}
prf->Init(prf->prfctx);
prf->Update(prf->prfctx, msg->exchange->message_id,
ISAKMP_HDR_MESSAGE_ID_LEN);
prf->Update(prf->prfctx, hash + hash_len,
msg->iov[0].iov_len - ISAKMP_HDR_SZ - hash_len);
prf->Final(comp_hash, prf->prfctx);
prf_free(prf);
if (memcmp(hash + ISAKMP_GEN_SZ, comp_hash, hash_len - ISAKMP_GEN_SZ)
!= 0) {
message_drop(msg, ISAKMP_NOTIFY_INVALID_HASH_INFORMATION,
0, 1, 0);
free(comp_hash);
return -1;
}
free(comp_hash);
/* Mark the HASH as handled. */
hashp->flags |= PL_MARK;
/* Mark message authenticated. */
msg->flags |= MSG_AUTHENTICATED;
return 0;
}
static int
pre_shared_decode_hash (struct message *msg)
{
struct exchange *exchange = msg->exchange;
struct ipsec_exch *ie = exchange->data;
struct payload *payload;
size_t hashsize = ie->hash->hashsize;
char header[80];
int initiator = exchange->initiator;
u_int8_t **hash_p;
/* Choose the right fields to fill-in. */
hash_p = initiator ? &ie->hash_r : &ie->hash_i;
payload = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_HASH]);
if (!payload)
{
log_print ("pre_shared_decode_hash: no HASH payload found");
return -1;
}
/* Check that the hash is of the correct size. */
if (GET_ISAKMP_GEN_LENGTH (payload->p) - ISAKMP_GEN_SZ != hashsize)
return -1;
/* XXX Need this hash be in the SA? */
*hash_p = malloc (hashsize);
if (!*hash_p)
{
log_error ("pre_shared_decode_hash: malloc (%lu) failed",
(unsigned long)hashsize);
return -1;
}
memcpy (*hash_p, payload->p + ISAKMP_HASH_DATA_OFF, hashsize);
snprintf (header, sizeof header, "pre_shared_decode_hash: HASH_%c",
initiator ? 'R' : 'I');
LOG_DBG_BUF ((LOG_MISC, 80, header, *hash_p, hashsize));
payload->flags |= PL_MARK;
return 0;
}
/*
* This function is used to validate the returned proposal (protection suite)
* we get from the responder against a proposal we sent. Only run as initiator.
* We return 0 if a match is found (in any transform of this proposal), 1
* otherwise. Also see note in sa_add_transform() below.
*/
static int
sa_validate_proto_xf(struct proto *match, struct payload *xf, int phase)
{
struct attr_validation_state *avs;
struct proto_attr *pa;
int found = 0;
size_t i;
u_int8_t xf_id;
if (!match->xf_cnt)
return 0;
if (match->proto != GET_ISAKMP_PROP_PROTO(xf->context->p)) {
LOG_DBG((LOG_SA, 70, "sa_validate_proto_xf: proto %p (#%d) "
"protocol mismatch", match, match->no));
return 1;
}
avs = (struct attr_validation_state *)calloc(1, sizeof *avs);
if (!avs) {
log_error("sa_validate_proto_xf: calloc (1, %lu)",
(unsigned long)sizeof *avs);
return 1;
}
avs->phase = phase;
/* Load the "proposal candidate" attribute set. */
(void)attribute_map(xf->p + ISAKMP_TRANSFORM_SA_ATTRS_OFF,
GET_ISAKMP_GEN_LENGTH(xf->p) - ISAKMP_TRANSFORM_SA_ATTRS_OFF,
sa_validate_xf_attrs, avs);
xf_id = GET_ISAKMP_TRANSFORM_ID(xf->p);
/* Check against the transforms we suggested. */
avs->mode++;
for (pa = TAILQ_FIRST(&match->xfs); pa && !found;
pa = TAILQ_NEXT(pa, next)) {
if (xf_id != GET_ISAKMP_TRANSFORM_ID(pa->attrs))
continue;
bzero(avs->checked, sizeof avs->checked);
if (attribute_map(pa->attrs + ISAKMP_TRANSFORM_SA_ATTRS_OFF,
pa->len - ISAKMP_TRANSFORM_SA_ATTRS_OFF,
sa_validate_xf_attrs, avs) == 0)
found++;
LOG_DBG((LOG_SA, 80, "sa_validate_proto_xf: attr_map "
"xf %p proto %p pa %p found %d", xf, match, pa, found));
if (!found)
continue;
/*
* Require all attributes present and checked. XXX perhaps
* not?
*/
for (i = 0; i < sizeof avs->checked; i++)
if (avs->attrp[i] && !avs->checked[i])
found = 0;
LOG_DBG((LOG_SA, 80, "sa_validate_proto_xf: req_attr "
"xf %p proto %p pa %p found %d", xf, match, pa, found));
}
free(avs);
return found ? 0 : 1;
}
/*
* As "the server", this starts REQ/REPLY (initiated by the client).
* As "the client", this starts SET/ACK (initiated by the server).
*/
static int
cfg_responder_recv_ATTR(struct message *msg)
{
struct payload *attrp = payload_first(msg, ISAKMP_PAYLOAD_ATTRIBUTE);
struct ipsec_exch *ie = msg->exchange->data;
struct sa *isakmp_sa = msg->isakmp_sa;
struct isakmp_cfg_attr *attr;
struct sockaddr *sa;
char *addr;
if (msg->exchange->phase == 2)
if (cfg_verify_hash(msg))
return -1;
ie->cfg_id = GET_ISAKMP_ATTRIBUTE_ID(attrp->p);
ie->cfg_type = attrp->p[ISAKMP_ATTRIBUTE_TYPE_OFF];
switch (ie->cfg_type) {
case ISAKMP_CFG_REQUEST:
case ISAKMP_CFG_SET:
break;
default:
message_drop(msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
log_print("cfg_responder_recv_ATTR: "
"unexpected configuration message type %d", ie->cfg_type);
return -1;
}
attribute_map(attrp->p + ISAKMP_ATTRIBUTE_ATTRS_OFF,
GET_ISAKMP_GEN_LENGTH(attrp->p) - ISAKMP_TRANSFORM_SA_ATTRS_OFF,
cfg_decode_attribute, ie);
switch (ie->cfg_type) {
case ISAKMP_CFG_REQUEST:
/* We're done. */
break;
case ISAKMP_CFG_SET: {
/* SET/ACK -- Client side (SET from server) */
const char *uk_addr = "<unknown>";
msg->transport->vtbl->get_dst(isakmp_sa->transport,
&sa);
if (sockaddr2text(sa, &addr, 0) < 0)
addr = (char *) uk_addr;
for (attr = LIST_FIRST(&ie->attrs); attr;
attr = LIST_NEXT(attr, link))
LOG_DBG((LOG_NEGOTIATION, 50,
"cfg_responder_recv_ATTR: "
"server %s asks us to SET attribute %s",
addr, constant_name(isakmp_cfg_attr_cst,
attr->type)));
/*
* XXX Here's the place to add code to walk through
* XXX each attribute and send them along to dhclient
* XXX or whatever. Each attribute that we act upon
* XXX (such as setting a netmask), should be marked
* XXX like this for us to send the proper ACK
* XXX response: attr->attr_used++;
*/
if (addr != uk_addr)
free(addr);
}
break;
default:
break;
}
attrp->flags |= PL_MARK;
return 0;
}
/*
* As "the server", this ends SET/ACK.
* As "the client", this ends REQ/REPLY.
*/
static int
cfg_initiator_recv_ATTR(struct message *msg)
{
struct payload *attrp = payload_first(msg, ISAKMP_PAYLOAD_ATTRIBUTE);
struct ipsec_exch *ie = msg->exchange->data;
struct sa *isakmp_sa = msg->isakmp_sa;
struct isakmp_cfg_attr *attr;
struct sockaddr *sa;
const char *uk_addr = "<unknown>";
char *addr;
if (msg->exchange->phase == 2)
if (cfg_verify_hash(msg))
return -1;
/* Sanity. */
if (ie->cfg_id != GET_ISAKMP_ATTRIBUTE_ID(attrp->p)) {
log_print("cfg_initiator_recv_ATTR: "
"cfg packet ID does not match!");
message_drop(msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
return -1;
}
switch (attrp->p[ISAKMP_ATTRIBUTE_TYPE_OFF]) {
case ISAKMP_CFG_ACK:
if (ie->cfg_type != ISAKMP_CFG_SET) {
log_print("cfg_initiator_recv_ATTR: "
"bad packet type ACK");
message_drop(msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED,
0, 1, 0);
return -1;
}
break;
case ISAKMP_CFG_REPLY:
if (ie->cfg_type != ISAKMP_CFG_REQUEST) {
log_print("cfg_initiator_recv_ATTR: "
"bad packet type REPLY");
message_drop(msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED,
0, 1, 0);
return -1;
}
break;
default:
log_print("cfg_initiator_recv_ATTR: unexpected configuration "
"message type %d", attrp->p[ISAKMP_ATTRIBUTE_TYPE_OFF]);
message_drop(msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
return -1;
}
attribute_map(attrp->p + ISAKMP_ATTRIBUTE_ATTRS_OFF,
GET_ISAKMP_GEN_LENGTH(attrp->p) - ISAKMP_TRANSFORM_SA_ATTRS_OFF,
cfg_decode_attribute, ie);
switch (ie->cfg_type) {
case ISAKMP_CFG_ACK: {
/* SET/ACK -- Server side (ACK from client) */
msg->transport->vtbl->get_src(isakmp_sa->transport,
&sa);
if (sockaddr2text(sa, &addr, 0) < 0)
addr = (char *) uk_addr;
for (attr = LIST_FIRST(&ie->attrs); attr;
attr = LIST_NEXT(attr, link))
LOG_DBG((LOG_NEGOTIATION, 50,
"cfg_initiator_recv_ATTR: "
"client %s ACKs attribute %s", addr,
constant_name(isakmp_cfg_attr_cst,
attr->type)));
if (addr != uk_addr)
free(addr);
}
break;
case ISAKMP_CFG_REPLY: {
/*
* REQ/REPLY: effect attributes we've gotten
* responses on.
*/
msg->transport->vtbl->get_src(isakmp_sa->transport,
&sa);
if (sockaddr2text(sa, &addr, 0) < 0)
addr = (char *) uk_addr;
for (attr = LIST_FIRST(&ie->attrs); attr;
attr = LIST_NEXT(attr, link))
LOG_DBG((LOG_NEGOTIATION, 50,
"cfg_initiator_recv_ATTR: "
"server %s replied with attribute %s",
addr, constant_name(isakmp_cfg_attr_cst,
attr->type)));
if (addr != uk_addr)
free(addr);
}
break;
default:
break;
}
attrp->flags |= PL_MARK;
return 0;
}
/* Receive ID. */
int
ike_phase_1_recv_ID (struct message *msg)
{
struct exchange *exchange = msg->exchange;
struct payload *payload;
char header[80], *rs = 0, *rid = 0, *p;
int initiator = exchange->initiator;
u_int8_t **id, id_type;
size_t *id_len, sz;
struct sockaddr *sa;
payload = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_ID]);
if (exchange->name)
rs = conf_get_str (exchange->name, "Remote-ID");
if (rs)
{
sz = ipsec_id_size (rs, &id_type);
if (sz == -1)
{
log_print ("ike_phase_1_recv_ID: could not handle specified "
"Remote-ID [%s]", rs);
return -1;
}
rid = malloc (sz);
if (!rid)
{
log_error ("ike_phase_1_recv_ID: malloc (%lu) failed",
(unsigned long)sz);
return -1;
}
switch (id_type)
{
case IPSEC_ID_IPV4_ADDR:
case IPSEC_ID_IPV6_ADDR:
p = conf_get_str (rs, "Address");
if (!p)
{
log_print ("ike_phase_1_recv_ID: "
"failed to get Address in Remote-ID section [%s]",
rs);
free (rid);
return -1;
}
if (text2sockaddr (p, 0, &sa) == -1)
{
log_print ("ike_phase_1_recv_ID: failed to parse address %s", p);
free (rid);
return -1;
}
if ((id_type == IPSEC_ID_IPV4_ADDR && sa->sa_family != AF_INET)
|| (id_type == IPSEC_ID_IPV6_ADDR && sa->sa_family != AF_INET6))
{
log_print ("ike_phase_1_recv_ID: "
"address %s not of expected family", p);
free (rid);
free (sa);
return -1;
}
memcpy (rid, sockaddr_addrdata (sa), sockaddr_addrlen (sa));
free (sa);
break;
case IPSEC_ID_FQDN:
case IPSEC_ID_USER_FQDN:
case IPSEC_ID_KEY_ID:
p = conf_get_str (rs, "Name");
if (!p)
{
log_print ("ike_phase_1_recv_ID: "
"failed to get Name in Remote-ID section [%s]", rs);
free (rid);
return -1;
}
memcpy (rid, p, sz);
break;
default:
log_print ("ike_phase_1_recv_ID: unsupported ID type %d", id_type);
free (rid);
return -1;
}
/* Compare expected/desired and received remote ID */
if (bcmp (rid, payload->p + ISAKMP_ID_DATA_OFF, sz))
{
free (rid);
log_print ("ike_phase_1_recv_ID: "
"received remote ID other than expected %s", p);
return -1;
}
free (rid);
}
/* Choose the right fields to fill in */
id = initiator ? &exchange->id_r : &exchange->id_i;
id_len = initiator ? &exchange->id_r_len : &exchange->id_i_len;
*id_len = GET_ISAKMP_GEN_LENGTH (payload->p) - ISAKMP_GEN_SZ;
*id = malloc (*id_len);
if (!*id)
{
log_error ("ike_phase_1_recv_ID: malloc (%lu) failed",
(unsigned long)*id_len);
return -1;
}
memcpy (*id, payload->p + ISAKMP_GEN_SZ, *id_len);
snprintf (header, sizeof header, "ike_phase_1_recv_ID: %s",
constant_name (ipsec_id_cst, GET_ISAKMP_ID_TYPE (payload->p)));
LOG_DBG_BUF ((LOG_NEGOTIATION, 40, header, payload->p + ISAKMP_ID_DATA_OFF,
*id_len + ISAKMP_GEN_SZ - ISAKMP_ID_DATA_OFF));
payload->flags |= PL_MARK;
return 0;
}
/* Validate a proposal inside SA according to EXCHANGE's policy. */
static int
ike_phase_1_validate_prop (struct exchange *exchange, struct sa *sa,
struct sa *isakmp_sa)
{
struct conf_list *conf, *tags;
struct conf_list_node *xf, *tag;
struct proto *proto;
struct validation_state vs;
struct attr_node *node, *next_node;
/* Get the list of transforms. */
conf = conf_get_list (exchange->policy, "Transforms");
if (!conf)
return 0;
for (xf = TAILQ_FIRST (&conf->fields); xf; xf = TAILQ_NEXT (xf, link))
{
for (proto = TAILQ_FIRST (&sa->protos); proto;
proto = TAILQ_NEXT (proto, link))
{
/* Mark all attributes in our policy as unseen. */
LIST_INIT (&vs.attrs);
vs.xf = xf;
vs.life = 0;
if (attribute_map (proto->chosen->p + ISAKMP_TRANSFORM_SA_ATTRS_OFF,
GET_ISAKMP_GEN_LENGTH (proto->chosen->p)
- ISAKMP_TRANSFORM_SA_ATTRS_OFF,
attribute_unacceptable, &vs))
goto try_next;
/* Sweep over unseen tags in this section. */
tags = conf_get_tag_list (xf->field);
if (tags)
{
for (tag = TAILQ_FIRST (&tags->fields); tag;
tag = TAILQ_NEXT (tag, link))
/*
* XXX Should we care about attributes we have, they do not
* provide?
*/
for (node = LIST_FIRST (&vs.attrs); node;
node = next_node)
{
next_node = LIST_NEXT (node, link);
if (node->type
== constant_value (ike_attr_cst, tag->field))
{
LIST_REMOVE (node, link);
free (node);
}
}
conf_free_list (tags);
}
/* Are there leftover tags in this section? */
node = LIST_FIRST (&vs.attrs);
if (node)
goto try_next;
}
/* All protocols were OK, we succeeded. */
LOG_DBG ((LOG_NEGOTIATION, 20, "ike_phase_1_validate_prop: success"));
conf_free_list (conf);
if (vs.life)
free (vs.life);
return 1;
try_next:
/* Are there leftover tags in this section? */
node = LIST_FIRST (&vs.attrs);
while (node)
{
LIST_REMOVE (node, link);
free (node);
node = LIST_FIRST (&vs.attrs);
}
if (vs.life)
free (vs.life);
}
LOG_DBG ((LOG_NEGOTIATION, 20, "ike_phase_1_validate_prop: failure"));
conf_free_list (conf);
return 0;
}
/* Decrypt the HASH in SIG, we already need a parsed ID payload. */
static int
rsa_sig_decode_hash (struct message *msg)
{
struct cert_handler *handler;
struct exchange *exchange = msg->exchange;
struct ipsec_exch *ie = exchange->data;
struct payload *p;
void *cert = 0;
u_int8_t *rawcert = 0;
u_int32_t rawcertlen;
RSA *key = 0;
size_t hashsize = ie->hash->hashsize;
char header[80];
int len;
int initiator = exchange->initiator;
u_int8_t **hash_p, **id_cert, *id;
u_int32_t *id_cert_len;
size_t id_len;
int found = 0, n, i, id_found;
#if defined (USE_DNSSEC)
u_int8_t *rawkey = 0;
u_int32_t rawkeylen;
#endif
/* Choose the right fields to fill-in. */
hash_p = initiator ? &ie->hash_r : &ie->hash_i;
id = initiator ? exchange->id_r : exchange->id_i;
id_len = initiator ? exchange->id_r_len : exchange->id_i_len;
if (!id || id_len == 0)
{
log_print ("rsa_sig_decode_hash: ID is missing");
return -1;
}
/*
* XXX Assume we should use the same kind of certification as the remote...
* moreover, just use the first CERT payload to decide what to use.
*/
p = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_CERT]);
if (!p)
handler = cert_get (ISAKMP_CERTENC_KEYNOTE);
else
handler = cert_get (GET_ISAKMP_CERT_ENCODING (p->p));
if (!handler)
{
log_print ("rsa_sig_decode_hash: cert_get (%d) failed",
p ? GET_ISAKMP_CERT_ENCODING (p->p) : -1);
return -1;
}
#if defined (USE_POLICY) && defined (USE_KEYNOTE)
/*
* We need the policy session initialized now, so we can add
* credentials etc.
*/
exchange->policy_id = kn_init ();
if (exchange->policy_id == -1)
{
log_print ("rsa_sig_decode_hash: failed to initialize policy session");
return -1;
}
#endif /* USE_POLICY || USE_KEYNOTE */
/* Obtain a certificate from our certificate storage. */
if (handler->cert_obtain (id, id_len, 0, &rawcert, &rawcertlen))
{
if (handler->id == ISAKMP_CERTENC_X509_SIG)
{
cert = handler->cert_get (rawcert, rawcertlen);
if (!cert)
LOG_DBG ((LOG_CRYPTO, 50,
"rsa_sig_decode_hash: certificate malformed"));
else
{
if (!handler->cert_get_key (cert, &key))
{
log_print ("rsa_sig_decode_hash: "
"decoding certificate failed");
handler->cert_free (cert);
}
else
{
found++;
LOG_DBG ((LOG_CRYPTO, 40,
"rsa_sig_decode_hash: using cert of type %d",
handler->id));
exchange->recv_cert = cert;
exchange->recv_certtype = handler->id;
#if defined (USE_POLICY)
x509_generate_kn (exchange->policy_id, cert);
#endif /* USE_POLICY */
}
}
}
else if (handler->id == ISAKMP_CERTENC_KEYNOTE)
handler->cert_insert (exchange->policy_id, rawcert);
free (rawcert);
}
/*
* Walk over potential CERT payloads in this message.
* XXX I believe this is the wrong spot for this. CERTs can appear
* anytime.
*/
for (p = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_CERT]); p;
p = TAILQ_NEXT (p, link))
{
p->flags |= PL_MARK;
/* When we have found a key, just walk over the rest, marking them. */
if (found)
continue;
handler = cert_get (GET_ISAKMP_CERT_ENCODING (p->p));
if (!handler)
{
LOG_DBG ((LOG_MISC, 30,
"rsa_sig_decode_hash: no handler for %s CERT encoding",
constant_name (isakmp_certenc_cst,
GET_ISAKMP_CERT_ENCODING (p->p))));
continue;
}
cert = handler->cert_get (p->p + ISAKMP_CERT_DATA_OFF,
GET_ISAKMP_GEN_LENGTH (p->p)
- ISAKMP_CERT_DATA_OFF);
if (!cert)
{
log_print ("rsa_sig_decode_hash: can not get data from CERT");
continue;
}
if (!handler->cert_validate (cert))
{
handler->cert_free (cert);
log_print ("rsa_sig_decode_hash: received CERT can't be validated");
continue;
}
if (GET_ISAKMP_CERT_ENCODING (p->p) == ISAKMP_CERTENC_X509_SIG)
{
if (!handler->cert_get_subjects (cert, &n, &id_cert, &id_cert_len))
{
handler->cert_free (cert);
log_print ("rsa_sig_decode_hash: can not get subject from CERT");
continue;
}
id_found = 0;
for (i = 0; i < n; i++)
if (id_cert_len[i] == id_len
&& id[0] == id_cert[i][0]
&& memcmp (id + 4, id_cert[i] + 4, id_len - 4) == 0)
{
id_found++;
break;
}
if (!id_found)
{
handler->cert_free (cert);
log_print ("rsa_sig_decode_hash: no CERT subject match the ID");
free (id_cert);
continue;
}
cert_free_subjects (n, id_cert, id_cert_len);
}
if (!handler->cert_get_key (cert, &key))
{
handler->cert_free (cert);
log_print ("rsa_sig_decode_hash: decoding payload CERT failed");
continue;
}
/* We validated the cert, cache it for later use. */
handler->cert_insert (exchange->policy_id, cert);
exchange->recv_cert = cert;
exchange->recv_certtype = GET_ISAKMP_CERT_ENCODING (p->p);
#if defined (USE_POLICY) && defined (USE_KEYNOTE)
if (exchange->recv_certtype == ISAKMP_CERTENC_KEYNOTE)
{
struct keynote_deckey dc;
char *pp;
int dclen;
dc.dec_algorithm = KEYNOTE_ALGORITHM_RSA;
dc.dec_key = key;
pp = kn_encode_key (&dc, INTERNAL_ENC_PKCS1, ENCODING_HEX,
KEYNOTE_PUBLIC_KEY);
if (pp == NULL)
{
kn_free_key (&dc);
log_print ("rsa_sig_decode_hash: failed to ASCII-encode key");
return -1;
}
dclen = strlen (pp) + sizeof "rsa-hex:";
exchange->keynote_key = calloc (dclen, sizeof (char));
if (!exchange->keynote_key)
{
free (pp);
kn_free_key (&dc);
log_print ("rsa_sig_decode_hash: failed to allocate %d bytes",
dclen);
return -1;
}
snprintf (exchange->keynote_key, dclen, "rsa-hex:%s", pp);
free (pp);
}
#endif
found++;
}
#if defined (USE_DNSSEC)
/* If no certificate provided a key, try to find a validated DNSSEC KEY. */
if (!found)
{
rawkey = dns_get_key (IKE_AUTH_RSA_SIG, msg, &rawkeylen);
/* We need to convert 'void *rawkey' into 'RSA *key'. */
if (dns_RSA_dns_to_x509 (rawkey, rawkeylen, &key) == 0)
found++;
else
log_print ("rsa_sig_decode_hash: KEY to RSA key conversion failed");
if (rawkey)
free (rawkey);
}
#endif /* USE_DNSSEC */
#if defined (USE_RAWKEY)
/* If we still have not found a key, try to read it from a file. */
if (!found)
if (get_raw_key_from_file (IKE_AUTH_RSA_SIG, id, id_len, &key) != -1)
found++;
#endif
if (!found)
{
log_print ("rsa_sig_decode_hash: no public key found");
return -1;
}
p = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_SIG]);
if (!p)
{
log_print ("rsa_sig_decode_hash: missing signature payload");
RSA_free (key);
return -1;
}
/* Check that the sig is of the correct size. */
len = GET_ISAKMP_GEN_LENGTH (p->p) - ISAKMP_SIG_SZ;
if (len != RSA_size (key))
{
RSA_free (key);
log_print ("rsa_sig_decode_hash: "
"SIG payload length does not match public key");
return -1;
}
*hash_p = malloc (len);
if (!*hash_p)
{
RSA_free (key);
log_error ("rsa_sig_decode_hash: malloc (%d) failed", len);
return -1;
}
len = RSA_public_decrypt (len, p->p + ISAKMP_SIG_DATA_OFF, *hash_p, key,
RSA_PKCS1_PADDING);
if (len == -1)
{
RSA_free (key);
log_print ("rsa_sig_decode_hash: RSA_public_decrypt () failed");
return -1;
}
/* Store key for later use */
exchange->recv_key = key;
exchange->recv_keytype = ISAKMP_KEY_RSA;
if (len != hashsize)
{
free (*hash_p);
*hash_p = 0;
log_print ("rsa_sig_decode_hash: len %lu != hashsize %lu",
(unsigned long)len, (unsigned long)hashsize);
return -1;
}
snprintf (header, sizeof header, "rsa_sig_decode_hash: HASH_%c",
initiator ? 'R' : 'I');
LOG_DBG_BUF ((LOG_MISC, 80, header, *hash_p, hashsize));
p->flags |= PL_MARK;
return 0;
}