uint8_t localN[NONCELEN]; /* Nonces for key exchange */
uint8_t remoteN[NONCELEN];
struct buffer_if buffer; /* Current outgoing key exchange packet */
+ struct buffer_if scratch;
int32_t retries; /* Number of retries remaining */
uint64_t timeout; /* Timeout for current state */
uint8_t *dhsecret;
static bool_t enter_state_resolve(struct site *st);
static bool_t enter_new_state(struct site *st,uint32_t next);
static void enter_state_wait(struct site *st);
+static void activate_new_key(struct site *st);
#define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
#define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
/* Give the netlink code an opportunity to put its own stuff in the
message (configuration information, etc.) */
- st->netlink->output_config(st->netlink->st,&st->buffer);
buf_prepend_uint32(&st->buffer,LABEL_MSG5);
st->new_transform->forwards(st->new_transform->st,&st->buffer,
&transform_err);
}
static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
- const struct comm_addr *src)
+ const struct comm_addr *src,
+ struct transform_inst_if *transform)
{
struct msg0 m;
cstring_t transform_err;
if (!unpick_msg0(st,msg5,&m)) return False;
- if (st->new_transform->reverse(st->new_transform->st,
- msg5,&transform_err)) {
+ if (transform->reverse(transform->st,msg5,&transform_err)) {
/* There's a problem */
slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
return False;
slog(st,LOG_SEC,"MSG5/PING packet contained wrong label");
return False;
}
- if (!st->netlink->check_config(st->netlink->st,msg5)) {
- slog(st,LOG_SEC,"MSG5/PING packet contained bad netlink config");
- return False;
- }
- CHECK_EMPTY(msg5);
+ /* Older versions of secnet used to write some config data here
+ * which we ignore. So we don't CHECK_EMPTY */
return True;
}
-static bool_t generate_msg6(struct site *st)
+static void create_msg6(struct site *st, struct transform_inst_if *transform,
+ uint32_t session_id)
{
cstring_t transform_err;
buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
/* Give the netlink code an opportunity to put its own stuff in the
message (configuration information, etc.) */
- st->netlink->output_config(st->netlink->st,&st->buffer);
buf_prepend_uint32(&st->buffer,LABEL_MSG6);
- st->new_transform->forwards(st->new_transform->st,&st->buffer,
- &transform_err);
+ transform->forwards(transform->st,&st->buffer,&transform_err);
buf_prepend_uint32(&st->buffer,LABEL_MSG6);
buf_prepend_uint32(&st->buffer,st->index);
- buf_prepend_uint32(&st->buffer,st->setup_session_id);
+ buf_prepend_uint32(&st->buffer,session_id);
+}
+static bool_t generate_msg6(struct site *st)
+{
+ create_msg6(st,st->new_transform,st->setup_session_id);
st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
return True;
}
slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data");
return False;
}
- if (!st->netlink->check_config(st->netlink->st,msg6)) {
- slog(st,LOG_SEC,"MSG6/PONG packet contained bad netlink config");
+ /* Older versions of secnet used to write some config data here
+ * which we ignore. So we don't CHECK_EMPTY */
+ return True;
+}
+
+static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0)
+{
+ cstring_t transform_err, newkey_err="n/a";
+ struct msg0 m;
+ uint32_t problem;
+
+ if (!unpick_msg0(st,msg0,&m)) return False;
+
+ /* Keep a copy so we can try decrypting it with multiple keys */
+ buffer_copy(&st->scratch, msg0);
+
+ problem = st->current_transform->reverse(st->current_transform->st,
+ msg0,&transform_err);
+ if (!problem) return True;
+
+ if (problem==2) {
+ slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
return False;
}
- CHECK_EMPTY(msg6);
- return True;
+
+ if (st->state==SITE_SENTMSG5) {
+ buffer_copy(msg0, &st->scratch);
+ if (!st->new_transform->reverse(st->new_transform->st,
+ msg0,&newkey_err)) {
+ /* It looks like we didn't get the peer's MSG6 */
+ /* This is like a cut-down enter_new_state(SITE_RUN) */
+ slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)");
+ BUF_FREE(&st->buffer);
+ st->timeout=0;
+ activate_new_key(st);
+ return True; /* do process the data in this packet */
+ }
+ }
+
+ slog(st,LOG_SEC,"transform: %s (new: %s)",transform_err,newkey_err);
+ initiate_key_setup(st,"incoming message would not decrypt");
+ return False;
}
static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
const struct comm_addr *src)
{
- struct msg0 m;
- cstring_t transform_err;
uint32_t type;
- if (!st->current_valid) {
- slog(st,LOG_DROP,"incoming message but no current key -> dropping");
- return initiate_key_setup(st,"incoming message but no current key");
- }
-
- if (!unpick_msg0(st,msg0,&m)) return False;
+ if (!decrypt_msg0(st,msg0))
+ return False;
- if (st->current_transform->reverse(st->current_transform->st,
- msg0,&transform_err)) {
- /* There's a problem */
- slog(st,LOG_SEC,"transform: %s",transform_err);
- return initiate_key_setup(st,"incoming message would not decrypt");
- }
CHECK_AVAIL(msg0,4);
type=buf_unprepend_uint32(msg0);
switch(type) {
const struct comm_addr *source)
{
struct site *st=sst;
+
+ if (buf->size < 12) return False;
+
uint32_t dest=ntohl(*(uint32_t *)buf->start);
if (dest==0) {
/* Setup packet: expected only in state SENTMSG4 */
/* (may turn up in state RUN if our return MSG6 was lost
and the new key has already been activated. In that
- case we should treat it as an ordinary PING packet. We
- can't pass it to process_msg5() because the
- new_transform will now be unkeyed. XXX) */
- if (st->state!=SITE_SENTMSG4) {
- slog(st,LOG_UNEXPECTED,"unexpected MSG5");
- } else if (process_msg5(st,buf,source)) {
- transport_setup_msgok(st,source);
- enter_new_state(st,SITE_RUN);
+ case we discard it. The peer will realise that we
+ are using the new key when they see our data packets.
+ Until then the peer's data packets to us get discarded. */
+ if (st->state==SITE_SENTMSG4) {
+ if (process_msg5(st,buf,source,st->new_transform)) {
+ transport_setup_msgok(st,source);
+ enter_new_state(st,SITE_RUN);
+ } else {
+ slog(st,LOG_SEC,"invalid MSG5");
+ }
+ } else if (st->state==SITE_RUN) {
+ if (process_msg5(st,buf,source,st->current_transform)) {
+ slog(st,LOG_DROP,"got MSG5, retransmitting MSG6");
+ transport_setup_msgok(st,source);
+ create_msg6(st,st->current_transform,st->remote_session_id);
+ transport_xmit(st,&st->peers,&st->buffer,True);
+ BUF_FREE(&st->buffer);
+ } else {
+ slog(st,LOG_SEC,"invalid MSG5 (in state RUN)");
+ }
} else {
- slog(st,LOG_SEC,"invalid MSG5");
+ slog(st,LOG_UNEXPECTED,"unexpected MSG5");
}
break;
case LABEL_MSG6:
st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
list_t *comms_cfg=dict_lookup(dict,"comm");
- if (!comms_cfg) cfgfatal(loc,"site","closure list \"comm\" not found");
+ if (!comms_cfg) cfgfatal(loc,"site","closure list \"comm\" not found\n");
st->ncomms=list_length(comms_cfg);
st->comms=safe_malloc_ary(sizeof(*st->comms),st->ncomms,"comms");
assert(st->ncomms);
for (i=0; i<st->ncomms; i++) {
item_t *item=list_elem(comms_cfg,i);
- if (item->type!=t_closure) cfgfatal(loc,"site","comm is not a closure");
+ if (item->type!=t_closure)
+ cfgfatal(loc,"site","comm is not a closure\n");
closure_t *cl=item->data.closure;
- if (cl->type!=CL_COMM) cfgfatal(loc,"site","comm closure wrong type");
+ if (cl->type!=CL_COMM) cfgfatal(loc,"site","comm closure wrong type\n");
st->comms[i]=cl->interface;
}
buffer_new(&st->buffer,SETUP_BUFFER_LEN);
+ buffer_new(&st->scratch,0);
+ BUF_ALLOC(&st->scratch,"site:scratch");
+
/* We are interested in poll(), but only for timeouts. We don't have
any fds of our own. */
register_for_poll(st, site_beforepoll, site_afterpoll, 0, "site");
dst->npeers=src->npeers;
memcpy(dst->peers, src->peers, sizeof(*dst->peers) * dst->npeers);
transport_peers_debug(st,dst,"copy",
- src->npeers, &src->peers->addr, sizeof(src->peers));
+ src->npeers, &src->peers->addr, sizeof(*src->peers));
}
void transport_xmit(struct site *st, transport_peers *peers,
~ian / secnet.git / blobdiff