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lightningd: allow a new channel open from peer if no *active* channels.
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And return the correct error message for the channel they give, if
they try to re-establish on an error channel.

Signed-off-by: Rusty Russell <[email protected]>
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@rustyrussell
rustyrussell committed Feb 12, 2018
1 parent 702cdf5 commit 26c4342
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Showing 2 changed files with 74 additions and 30 deletions.
80 changes: 50 additions & 30 deletions lightningd/peer_control.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -89,12 +89,6 @@ static void peer_accept_channel(struct lightningd *ld,
int peer_fd, int gossip_fd,
const u8 *open_msg);

/* FIXME: This is here until we get multi-channel support */
static struct channel *peer2channel(const struct peer *peer)
{
return list_top(&peer->channels, struct channel, list);
}

static void destroy_peer(struct peer *peer)
{
list_del_from(&peer->ld->peers, &peer->list);
Expand Down Expand Up @@ -287,7 +281,7 @@ void peer_connected(struct lightningd *ld, const u8 *msg,
u8 *error;
u8 *supported_global_features;
u8 *supported_local_features;
struct peer *peer;
struct channel *channel;
struct wireaddr addr;
u64 gossip_index;

Expand Down Expand Up @@ -316,16 +310,15 @@ void peer_connected(struct lightningd *ld, const u8 *msg,
goto send_error;
}

/* Now, do we already know this peer? */
peer = peer_by_id(ld, &id);
if (peer) {
/* FIXME: Only consider active channels! */
struct channel *channel = peer2channel(peer);

/* If we're already dealing with this peer, hand off to correct
* subdaemon. Otherwise, we'll respond iff they ask about an inactive
* channel. */
channel = active_channel_by_id(ld, &id);
if (channel) {
log_debug(channel->log, "Peer has reconnected, state %s",
channel_state_name(channel));

/* FIXME: We can have errors for multiple channels. */
/* If we have a canned error, deliver it now. */
if (channel->error) {
error = channel->error;
goto send_error;
Expand Down Expand Up @@ -355,9 +348,9 @@ void peer_connected(struct lightningd *ld, const u8 *msg,
case ONCHAIND_OUR_UNILATERAL:
case FUNDING_SPEND_SEEN:
case ONCHAIND_MUTUAL:
/* If they try to reestablish channel, we'll send
* error then */
goto return_to_gossipd;
case CLOSINGD_COMPLETE:
/* Channel is active! */
abort();

case CHANNELD_AWAITING_LOCKIN:
case CHANNELD_NORMAL:
Expand All @@ -366,19 +359,18 @@ void peer_connected(struct lightningd *ld, const u8 *msg,
* on this peer. */
channel_set_owner(channel, NULL);

peer->addr = addr;
channel->peer->addr = addr;
peer_start_channeld(channel, &cs, gossip_index,
peer_fd, gossip_fd, NULL,
true);
goto connected;

case CLOSINGD_SIGEXCHANGE:
case CLOSINGD_COMPLETE:
/* Stop any existing daemon, without triggering error
* on this peer. */
channel_set_owner(channel, NULL);

peer->addr = addr;
channel->peer->addr = addr;
peer_start_closingd(channel, &cs, gossip_index,
peer_fd, gossip_fd,
true);
Expand Down Expand Up @@ -455,6 +447,27 @@ void peer_connection_failed(struct lightningd *ld, const u8 *msg)
}
}

static struct channel *channel_by_channel_id(struct peer *peer,
const struct channel_id *channel_id)
{
struct channel *channel;

list_for_each(&peer->channels, channel, list) {
struct channel_id cid;

if (!channel->funding_txid)
continue;

derive_channel_id(&cid,
channel->funding_txid,
channel->funding_outnum);
if (structeq(&cid, channel_id))
return channel;
}
return NULL;
}

/* We only get here IF we weren't trying to connect to it. */
void peer_sent_nongossip(struct lightningd *ld,
const struct pubkey *id,
const struct wireaddr *addr,
Expand All @@ -474,28 +487,35 @@ void peer_sent_nongossip(struct lightningd *ld,
else
channel_id = &extracted_channel_id;

/* FIXME: match state too; we can have multiple onchain
* (ie. dead) channels for the same peer. */
peer = peer_by_id(ld, id);
if (peer) {
error = towire_errorfmt(ld, channel_id,
"Unexpected message %i in state %s",
fromwire_peektype(in_msg),
channel_state_name(peer2channel(peer)));
goto send_error;
}

/* Open request? */
if (fromwire_peektype(in_msg) == WIRE_OPEN_CHANNEL) {
if (peer && peer_active_channel(peer)) {
error = towire_errorfmt(in_msg, channel_id,
"Multiple channels unsupported");
goto send_error;
}
peer_accept_channel(ld, id, addr, cs, gossip_index,
gfeatures, lfeatures,
peer_fd, gossip_fd, in_msg);
return;
}

/* If they are talking about a specific channel id, we may have an
* error for them. */
if (peer && channel_id) {
struct channel *channel;
channel = channel_by_channel_id(peer, channel_id);
if (channel && channel->error) {
error = channel->error;
goto send_error;
}
}

/* Weird request. */
error = towire_errorfmt(ld, channel_id,
"Unexpected message %i for unknown peer",
"Unexpected message %i for peer",
fromwire_peektype(in_msg));

send_error:
Expand Down
24 changes: 24 additions & 0 deletions tests/test_lightningd.py
View file
Original file line number Diff line number Diff line change
Expand Up @@ -3382,6 +3382,30 @@ def test_listconfigs(self):
oneconfig = l1.rpc.listconfigs(c)
assert(oneconfig[c] == configs[c])

def test_multiple_channels(self):
l1 = self.node_factory.get_node()
l2 = self.node_factory.get_node()

for i in range(3):
# FIXME: we shouldn't disconnect on close?
ret = l1.rpc.connect(l2.info['id'], 'localhost', l2.info['port'])
assert ret['id'] == l2.info['id']

l1.daemon.wait_for_log('WIRE_GOSSIPCTL_HAND_BACK_PEER')
l2.daemon.wait_for_log('WIRE_GOSSIPCTL_HAND_BACK_PEER')
chanid = self.fund_channel(l1, l2, 10**6)

l1.rpc.close(l2.info['id'])
l1.daemon.wait_for_log(' to CLOSINGD_COMPLETE')
l2.daemon.wait_for_log(' to CLOSINGD_COMPLETE')

channels = l1.rpc.listpeers()['peers'][0]['channels']
assert len(channels) == 3
# Most in state ONCHAIND_MUTUAL, last is CLOSINGD_COMPLETE
for i in range(len(channels)-1):
assert channels[i]['state'] == 'ONCHAIND_MUTUAL'
assert channels[-1]['state'] == 'CLOSINGD_COMPLETE'

def test_cli(self):
l1 = self.node_factory.get_node()

Expand Down

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