after this time, initiate a new
key exchange */
- bool_t setup_priority; /* Do we have precedence if both sites emit
- message 1 simultaneously? */
+ bool_t our_name_later; /* our name > peer name */
uint32_t log_events;
/* runtime information */
uint32_t state;
uint64_t now; /* Most recently seen time */
bool_t allow_send_prod;
+ bool_t msg1_crossed_logged;
int resolving_count;
int resolving_n_results_all;
int resolving_n_results_stored;
}
#define DEFINE_CALL_TRANSFORM(fwdrev) \
-static int call_transform_##fwdrev(struct site *st, \
+static transform_apply_return \
+call_transform_##fwdrev(struct site *st, \
struct transform_inst_if *transform, \
struct buffer_if *buf, \
const char **errmsg) \
{ \
if (!is_transform_valid(transform)) { \
*errmsg="transform not set up"; \
- return 1; \
+ return transform_apply_err; \
} \
return transform->fwdrev(transform->st,buf,errmsg); \
}
char *sig;
};
-static void set_new_transform(struct site *st, char *pk)
+static _Bool set_new_transform(struct site *st, char *pk)
{
+ _Bool ok;
+
/* Make room for the shared key */
st->sharedsecretlen=st->chosen_transform->keylen?:st->dh->ceil_len;
assert(st->sharedsecretlen);
/* Set up the transform */
struct transform_if *generator=st->chosen_transform;
struct transform_inst_if *generated=generator->create(generator->st);
- generated->setkey(generated->st,st->sharedsecret,
- st->sharedsecretlen,st->setup_priority);
+ ok = generated->setkey(generated->st,st->sharedsecret,
+ st->sharedsecretlen,st->our_name_later);
+
dispose_transform(&st->new_transform);
+ if (!ok) return False;
st->new_transform=generated;
slog(st,LOG_SETUP_INIT,"key exchange negotiated transform"
" %d (capabilities ours=%#"PRIx32" theirs=%#"PRIx32")",
st->chosen_transform->capab_transformnum,
st->local_capabilities, st->remote_capabilities);
+ return True;
}
struct xinfoadd {
st->random->generate(st->random->st,st->dh->len,st->dhsecret);
/* Generate the shared key and set up the transform */
- set_new_transform(st,m.pk);
+ if (!set_new_transform(st,m.pk)) return False;
return True;
}
m.pk[m.pklen]=0;
/* Generate the shared key and set up the transform */
- set_new_transform(st,m.pk);
+ if (!set_new_transform(st,m.pk)) return False;
return True;
}
/* Give the netlink code an opportunity to put its own stuff in the
message (configuration information, etc.) */
buf_prepend_uint32(&st->buffer,LABEL_MSG6);
- int problem = call_transform_forwards(st,transform,
- &st->buffer,&transform_err);
+ transform_apply_return problem =
+ call_transform_forwards(st,transform,
+ &st->buffer,&transform_err);
assert(!problem);
buf_prepend_uint32(&st->buffer,LABEL_MSG6);
buf_prepend_uint32(&st->buffer,st->index);
return True;
}
-static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0,
+static transform_apply_return
+decrypt_msg0(struct site *st, struct buffer_if *msg0,
const struct comm_addr *src)
{
cstring_t transform_err, auxkey_err, newkey_err="n/a";
struct msg0 m;
- uint32_t problem;
+ transform_apply_return problem;
if (!unpick_msg0(st,msg0,&m)) return False;
if (!st->auxiliary_is_new)
delete_one_key(st,&st->auxiliary_key,
"peer has used new key","auxiliary key",LOG_SEC);
- return True;
+ return 0;
}
- if (problem==2)
- goto skew;
+ if (transform_apply_return_badseq(problem))
+ goto badseq;
buffer_copy(msg0, &st->scratch);
problem = call_transform_reverse(st,st->auxiliary_key.transform,
msg0,&auxkey_err);
- if (problem==0) {
+ if (!problem) {
slog(st,LOG_DROP,"processing packet which uses auxiliary key");
if (st->auxiliary_is_new) {
/* We previously timed out in state SENTMSG5 but it turns
st->auxiliary_is_new=0;
st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
}
- return True;
+ return 0;
}
- if (problem==2)
- goto skew;
+ if (transform_apply_return_badseq(problem))
+ goto badseq;
if (st->state==SITE_SENTMSG5) {
buffer_copy(msg0, &st->scratch);
BUF_FREE(&st->buffer);
st->timeout=0;
activate_new_key(st);
- return True; /* do process the data in this packet */
+ return 0; /* do process the data in this packet */
}
- if (problem==2)
- goto skew;
+ if (transform_apply_return_badseq(problem))
+ goto badseq;
}
slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)",
transform_err,auxkey_err,newkey_err);
initiate_key_setup(st,"incoming message would not decrypt",0);
send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt");
- return False;
+ assert(problem);
+ return problem;
- skew:
- slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
- return False;
+ badseq:
+ slog(st,LOG_DROP,"transform: %s (bad seq.)",transform_err);
+ assert(problem);
+ return problem;
}
static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
const struct comm_addr *src)
{
uint32_t type;
-
- if (!decrypt_msg0(st,msg0,src))
+ transform_apply_return problem;
+
+ problem = decrypt_msg0(st,msg0,src);
+ if (problem==transform_apply_seqdupe) {
+ /* We recently received another copy of this packet, maybe due
+ * to polypath. That's not a problem; indeed, for the
+ * purposes of transport address management it is a success.
+ * But we don't want to process the packet. */
+ transport_data_msgok(st,src);
+ return False;
+ }
+ if (problem)
return False;
CHECK_AVAIL(msg0,4);
case SITE_SENTMSG1:
state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
gen=generate_msg1;
+ st->msg1_crossed_logged = False;
break;
case SITE_SENTMSG2:
state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
&& name_matches(&m->local,st->localname);
}
+static bool_t we_have_priority(struct site *st, const struct msg *m) {
+ if ((st->local_capabilities & m->remote_capabilities)
+ && CAPAB_PRIORITY_MOBILE) {
+ if (st->local_mobile) return True;
+ if (st-> peer_mobile) return False;
+ }
+ return st->our_name_later;
+}
+
+static bool_t setup_late_msg_ok(struct site *st,
+ const struct buffer_if *buf_in,
+ uint32_t msgtype,
+ const struct comm_addr *source) {
+ /* For setup packets which seem from their type like they are
+ * late. Maybe they came via a different path. All we do is make
+ * a note of the sending address, iff they look like they are part
+ * of the current key setup attempt. */
+ struct msg m;
+ if (!named_for_us(st,buf_in,msgtype,&m))
+ /* named_for_us calls unpick_msg which gets the nonces */
+ return False;
+ if (!consttime_memeq(m.nR,st->remoteN,NONCELEN) ||
+ !consttime_memeq(m.nL,st->localN, NONCELEN))
+ /* spoof ? from stale run ? who knows */
+ return False;
+ transport_setup_msgok(st,source);
+ return True;
+}
+
/* This function is called by the communication device to deliver
packets from our peers.
It should return True if the packet is recognised as being for
/* We've just sent a message 1! They may have crossed on
the wire. If we have priority then we ignore the
incoming one, otherwise we process it as usual. */
- if (st->setup_priority) {
+ if (we_have_priority(st,&named_msg)) {
BUF_FREE(buf);
- slog(st,LOG_DUMP,"crossed msg1s; we are higher "
- "priority => ignore incoming msg1");
+ if (!st->msg1_crossed_logged++)
+ slog(st,LOG_SETUP_INIT,"crossed msg1s; we are higher "
+ "priority => ignore incoming msg1");
return True;
} else {
- slog(st,LOG_DUMP,"crossed msg1s; we are lower "
+ slog(st,LOG_SETUP_INIT,"crossed msg1s; we are lower "
"priority => use incoming msg1");
if (process_msg1(st,buf,source,&named_msg)) {
BUF_FREE(&st->buffer); /* Free our old message 1 */
BUF_FREE(buf);
return True;
}
+ } else if (st->state==SITE_SENTMSG2 ||
+ st->state==SITE_SENTMSG4) {
+ if (consttime_memeq(named_msg.nR,st->remoteN,NONCELEN)) {
+ /* We are ahead in the protocol, but that msg1 had the
+ * peer's nonce so presumably it is from this key
+ * exchange run, via a slower route */
+ transport_setup_msgok(st,source);
+ } else {
+ slog(st,LOG_UNEXPECTED,"competing incoming message 1");
+ }
+ BUF_FREE(buf);
+ return True;
}
/* The message 1 was received at an unexpected stage of the
- key setup. XXX POLICY - what do we do? */
+ key setup. Well, they lost the race. */
slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
BUF_FREE(buf);
return True;
case LABEL_MSG2:
/* Setup packet: expected only in state SENTMSG1 */
if (st->state!=SITE_SENTMSG1) {
+ if ((st->state==SITE_SENTMSG3 ||
+ st->state==SITE_SENTMSG5) &&
+ setup_late_msg_ok(st,buf,msgtype,source))
+ break;
slog(st,LOG_UNEXPECTED,"unexpected MSG2");
} else if (process_msg2(st,buf,source)) {
transport_setup_msgok(st,source);
case LABEL_MSG3BIS:
/* Setup packet: expected only in state SENTMSG2 */
if (st->state!=SITE_SENTMSG2) {
+ if ((st->state==SITE_SENTMSG4) &&
+ setup_late_msg_ok(st,buf,msgtype,source))
+ break;
slog(st,LOG_UNEXPECTED,"unexpected MSG3");
} else if (process_msg3(st,buf,source,msgtype)) {
transport_setup_msgok(st,source);
case LABEL_MSG4:
/* Setup packet: expected only in state SENTMSG3 */
if (st->state!=SITE_SENTMSG3) {
+ if ((st->state==SITE_SENTMSG5) &&
+ setup_late_msg_ok(st,buf,msgtype,source))
+ break;
slog(st,LOG_UNEXPECTED,"unexpected MSG4");
} else if (process_msg4(st,buf,source)) {
transport_setup_msgok(st,source);
/* The information we expect to see in incoming messages of type 1 */
/* fixme: lots of unchecked overflows here, but the results are only
corrupted packets rather than undefined behaviour */
- st->setup_priority=(strcmp(st->localname,st->remotename)>0);
+ st->our_name_later=(strcmp(st->localname,st->remotename)>0);
buffer_new(&st->buffer,SETUP_BUFFER_LEN);
st->local_capabilities |= capbit;
}
+ if (st->local_mobile || st->peer_mobile)
+ st->local_capabilities |= CAPAB_PRIORITY_MOBILE;
+
/* We need to register the remote networks with the netlink device */
uint32_t netlink_mtu; /* local virtual interface mtu */
st->netlink->reg(st->netlink->st, site_outgoing, st, &netlink_mtu);
*
* Caller must first call transport_peers_expire. */
- if (naddrs==1 && peers->npeers>=1 &&
- comm_addr_equal(&addrs[0], &peers->peers[0].addr)) {
- /* optimisation, also avoids debug for trivial updates */
- peers->peers[0].last = *tv_now;
- return;
+ if (naddrs==1) {
+ /* avoids debug for uninteresting updates */
+ int i;
+ for (i=0; i<peers->npeers; i++) {
+ if (comm_addr_equal(&addrs[0], &peers->peers[i].addr)) {
+ memmove(peers->peers+1, peers->peers,
+ sizeof(peers->peers[0]) * i);
+ peers->peers[0].addr = addrs[0];
+ peers->peers[0].last = *tv_now;
+ return;
+ }
+ }
}
int old_npeers=peers->npeers;
~ianmdlvl / secnet.git / blobdiff