/* The currently established session */
struct data_key current;
+ struct data_key auxiliary_key;
+ bool_t auxiliary_is_new;
uint64_t renegotiate_key_time; /* When we can negotiate a new key */
+ uint64_t auxiliary_renegotiate_key_time;
transport_peers peers; /* Current address(es) of peer for data traffic */
/* The current key setup protocol exchange. We can only be
}
static void set_link_quality(struct site *st);
-static void delete_key(struct site *st, cstring_t reason, uint32_t loglevel);
+static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel);
+static void delete_one_key(struct site *st, struct data_key *key,
+ const char *reason /* may be 0 meaning don't log*/,
+ const char *which /* ignored if !reasonn */,
+ uint32_t loglevel /* ignored if !reasonn */);
static bool_t initiate_key_setup(struct site *st, cstring_t reason);
static void enter_state_run(struct site *st);
static bool_t enter_state_resolve(struct site *st);
return False;
}
if (type==LABEL_MSG2) return True;
- if (memcmp(m->nR,st->remoteN,NONCELEN)!=0) {
+ if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) {
*error="wrong remotely-generated nonce";
return False;
}
static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0)
{
- cstring_t transform_err, newkey_err="n/a";
+ cstring_t transform_err, auxkey_err, newkey_err="n/a";
struct msg0 m;
uint32_t problem;
problem = st->current.transform->reverse(st->current.transform->st,
msg0,&transform_err);
- if (!problem) return True;
+ if (!problem) {
+ if (!st->auxiliary_is_new)
+ delete_one_key(st,&st->auxiliary_key,
+ "peer has used new key","auxiliary key",LOG_SEC);
+ return True;
+ }
if (problem==2) {
slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
return False;
}
+ buffer_copy(msg0, &st->scratch);
+ problem = st->auxiliary_key.transform->reverse
+ (st->auxiliary_key.transform->st,msg0,&auxkey_err);
+ if (problem==0) {
+ 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
+ * out that our peer did in fact get our MSG5 and is
+ * using the new key. So we should switch to it too. */
+ /* This is a bit like activate_new_key. */
+ struct data_key t;
+ t=st->current;
+ st->current=st->auxiliary_key;
+ st->auxiliary_key=t;
+
+ delete_one_key(st,&st->auxiliary_key,"peer has used new key",
+ "previous key",LOG_SEC);
+ st->auxiliary_is_new=0;
+ st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
+ }
+ return True;
+ }
+
if (st->state==SITE_SENTMSG5) {
buffer_copy(msg0, &st->scratch);
if (!st->new_transform->reverse(st->new_transform->st,
}
}
- slog(st,LOG_SEC,"transform: %s (new: %s)",transform_err,newkey_err);
+ 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");
return False;
}
switch(type) {
case LABEL_MSG7:
/* We must forget about the current session. */
- delete_key(st,"request from peer",LOG_SEC);
+ delete_keys(st,"request from peer",LOG_SEC);
return True;
case LABEL_MSG9:
/* Deliver to netlink layer */
st->timeout=st->now+st->setup_retry_interval;
st->retries--;
return True;
+ } else if (st->state==SITE_SENTMSG5) {
+ slog(st,LOG_SETUP_TIMEOUT,"timed out sending MSG5, stashing new key");
+ /* We stash the key we have produced, in case it turns out that
+ * our peer did see our MSG5 after all and starts using it. */
+ /* This is a bit like some of activate_new_key */
+ struct transform_inst_if *t;
+ t=st->auxiliary_key.transform;
+ st->auxiliary_key.transform=st->new_transform;
+ st->new_transform=t;
+
+ t->delkey(t->st);
+ st->auxiliary_is_new=1;
+ st->auxiliary_key.key_timeout=st->now+st->key_lifetime;
+ st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time;
+ st->auxiliary_key.remote_session_id=st->setup_session_id;
+
+ enter_state_wait(st);
+ return False;
} else {
slog(st,LOG_SETUP_TIMEOUT,"timed out sending key setup packet "
"(in state %s)",state_name(st->state));
{
struct transform_inst_if *t;
- /* We have two transform instances, which we swap between active
- and setup */
- t=st->current.transform;
+ /* We have three transform instances, which we swap between old,
+ active and setup */
+ t=st->auxiliary_key.transform;
+ st->auxiliary_key.transform=st->current.transform;
st->current.transform=st->new_transform;
st->new_transform=t;
t->delkey(t->st);
st->timeout=0;
+ st->auxiliary_is_new=0;
+ st->auxiliary_key.key_timeout=st->current.key_timeout;
st->current.key_timeout=st->now+st->key_lifetime;
st->renegotiate_key_time=st->now+st->key_renegotiate_time;
transport_peers_copy(st,&st->peers,&st->setup_peers);
enter_state_run(st);
}
-static void delete_key(struct site *st, cstring_t reason, uint32_t loglevel)
+static void delete_one_key(struct site *st, struct data_key *key,
+ cstring_t reason, cstring_t which, uint32_t loglevel)
+{
+ if (!key->transform->valid(key->transform->st)) return;
+ if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
+ key->transform->delkey(key->transform->st);
+ key->key_timeout=0;
+}
+
+static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
{
if (current_valid(st)) {
slog(st,loglevel,"session closed (%s)",reason);
- st->current.transform->delkey(st->current.transform->st);
- st->current.key_timeout=0;
+ delete_one_key(st,&st->current,0,0,0);
set_link_quality(st);
}
+ delete_one_key(st,&st->auxiliary_key,0,0,0);
}
static void state_assert(struct site *st, bool_t ok)
{
st->state=SITE_STOP;
st->timeout=0;
- delete_key(st,"entering state STOP",LOG_TIMEOUT_KEY);
+ delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
st->new_transform->delkey(st->new_transform->st);
}
active. */
site_settimeout(st->timeout, timeout_io);
site_settimeout(st->current.key_timeout, timeout_io);
+ site_settimeout(st->auxiliary_key.key_timeout, timeout_io);
return 0; /* success */
}
+static void check_expiry(struct site *st, struct data_key *key,
+ const char *which)
+{
+ if (key->key_timeout && *now>key->key_timeout) {
+ delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY);
+ }
+}
+
/* NB site_afterpoll will be called before site_beforepoll is ever called */
static void site_afterpoll(void *sst, struct pollfd *fds, int nfds)
{
st->state);
}
}
- if (st->current.key_timeout && *now>st->current.key_timeout) {
- delete_key(st,"maximum key life exceeded",LOG_TIMEOUT_KEY);
- }
+ check_expiry(st,&st->current,"current key");
+ check_expiry(st,&st->auxiliary_key,"auxiliary key");
}
/* This function is called by the netlink device to deliver packets
st->timeout=0;
st->current.key_timeout=0;
+ st->auxiliary_key.key_timeout=0;
transport_peers_clear(st,&st->peers);
transport_peers_clear(st,&st->setup_peers);
/* XXX mlock these */
st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
st->current.transform=st->transform->create(st->transform->st);
+ st->auxiliary_key.transform=st->transform->create(st->transform->st);
st->new_transform=st->transform->create(st->transform->st);
+ st->auxiliary_is_new=0;
enter_state_stop(st);