/*~ Welcome to the gossip daemon: keeper of maps!
*
* This is the last "global" daemon; it has three purposes.
*
* 1. To determine routes for payments when lightningd asks.
* 2. The second purpose is to receive gossip from peers (via their
* per-peer daemons) and send it out to them.
* 3. Talk to `connectd` to to answer address queries for nodes.
*
* The gossip protocol itself is fairly simple, but has some twists which
* add complexity to this daemon.
*/
#include <bitcoin/chainparams.h>
#include <ccan/array_size/array_size.h>
#include <ccan/build_assert/build_assert.h>
#include <ccan/cast/cast.h>
#include <ccan/container_of/container_of.h>
#include <ccan/crypto/hkdf_sha256/hkdf_sha256.h>
#include <ccan/crypto/siphash24/siphash24.h>
#include <ccan/endian/endian.h>
#include <ccan/fdpass/fdpass.h>
#include <ccan/io/fdpass/fdpass.h>
#include <ccan/io/io.h>
#include <ccan/mem/mem.h>
#include <ccan/noerr/noerr.h>
#include <ccan/take/take.h>
#include <ccan/tal/str/str.h>
#include <common/bech32.h>
#include <common/bech32_util.h>
#include <common/cryptomsg.h>
#include <common/daemon_conn.h>
#include <common/features.h>
#include <common/memleak.h>
#include <common/ping.h>
#include <common/pseudorand.h>
#include <common/status.h>
#include <common/subdaemon.h>
#include <common/timeout.h>
#include <common/type_to_string.h>
#include <common/utils.h>
#include <common/version.h>
#include <common/wire_error.h>
#include <common/wireaddr.h>
#include <connectd/connectd_gossipd_wiregen.h>
#include <errno.h>
#include <fcntl.h>
#include <gossipd/broadcast.h>
#include <gossipd/gossip_generation.h>
#include <gossipd/gossip_store_wiregen.h>
#include <gossipd/gossipd.h>
#include <gossipd/gossipd_peerd_wiregen.h>
#include <gossipd/gossipd_wiregen.h>
#include <gossipd/queries.h>
#include <gossipd/routing.h>
#include <gossipd/seeker.h>
#include <inttypes.h>
#include <lightningd/gossip_msg.h>
#include <netdb.h>
#include <netinet/in.h>
#include <secp256k1_ecdh.h>
#include <sodium/randombytes.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/un.h>
#include <unistd.h>
#include <wire/wire_io.h>
#include <wire/wire_sync.h>
/*~ A channel consists of a `struct half_chan` for each direction, each of
* which has a `flags` word from the `channel_update`; bit 1 is
* ROUTING_FLAGS_DISABLED in the `channel_update`. But we also keep a local
* whole-channel flag which indicates it's not available; we use this when a
* peer disconnects, and generate a `channel_update` to tell the world lazily
* when someone asks. */
static void peer_disable_channels(struct daemon *daemon, struct node *node)
{
/* If this peer had a channel with us, mark it disabled. */
struct chan_map_iter i;
struct chan *c;
for (c = first_chan(node, &i); c; c = next_chan(node, &i)) {
if (node_id_eq(&other_node(node, c)->id, &daemon->id))
local_disable_chan(daemon->rstate, c);
}
}
/*~ Destroy a peer, usually because the per-peer daemon has exited.
*
* Were you wondering why we call this "destroy_peer" and not "peer_destroy"?
* I thought not! But while CCAN modules are required to keep to their own
* prefix namespace, leading to unnatural word order, we couldn't stomach that
* for our own internal use. We use 'find_foo', 'destroy_foo' and 'new_foo'.
*/
static void destroy_peer(struct peer *peer)
{
struct node *node;
/* Remove it from the peers list */
list_del_from(&peer->daemon->peers, &peer->list);
/* If we have a channel with this peer, disable it. */
node = get_node(peer->daemon->rstate, &peer->id);
if (node)
peer_disable_channels(peer->daemon, node);
/* This is tricky: our lifetime is tied to the daemon_conn; it's our
* parent, so we are freed if it is, but we need to free it if we're
* freed manually. tal_free() treats this as a noop if it's already
* being freed */
tal_free(peer->dc);
}
/* Search for a peer. */
struct peer *find_peer(struct daemon *daemon, const struct node_id *id)
{
struct peer *peer;
list_for_each(&daemon->peers, peer, list)
if (node_id_eq(&peer->id, id))
return peer;
return NULL;
}
/* Increase a peer's gossip_counter, if peer not NULL */
void peer_supplied_good_gossip(struct peer *peer, size_t amount)
{
if (peer)
peer->gossip_counter += amount;
}
/* Queue a gossip message for the peer: the subdaemon on the other end simply
* forwards it to the peer. */
void queue_peer_msg(struct peer *peer, const u8 *msg TAKES)
{
daemon_conn_send(peer->dc, msg);
}
/*~ We have a helper for messages from the store. */
void queue_peer_from_store(struct peer *peer,
const struct broadcastable *bcast)
{
struct gossip_store *gs = peer->daemon->rstate->gs;
queue_peer_msg(peer, take(gossip_store_get(NULL, gs, bcast->index)));
}
/*~ We don't actually keep node_announcements in memory; we keep them in
* a file called `gossip_store`. If we need some node details, we reload
* and reparse. It's slow, but generally rare. */
static bool get_node_announcement(const tal_t *ctx,
struct daemon *daemon,
const struct node *n,
u8 rgb_color[3],
u8 alias[32],
u8 **features,
struct wireaddr **wireaddrs)
{
const u8 *msg;
struct node_id id;
secp256k1_ecdsa_signature signature;
u32 timestamp;
u8 *addresses;
if (!n->bcast.index)
return false;
msg = gossip_store_get(tmpctx, daemon->rstate->gs, n->bcast.index);
/* Note: validity of node_id is already checked. */
if (!fromwire_node_announcement(ctx, msg,
&signature, features,
×tamp,
&id, rgb_color, alias,
&addresses)) {
status_broken("Bad local node_announcement @%u: %s",
n->bcast.index, tal_hex(tmpctx, msg));
return false;
}
if (!node_id_eq(&id, &n->id) || timestamp != n->bcast.timestamp) {
status_broken("Wrong node_announcement @%u:"
" expected %s timestamp %u "
" got %s timestamp %u",
n->bcast.index,
type_to_string(tmpctx, struct node_id, &n->id),
timestamp,
type_to_string(tmpctx, struct node_id, &id),
n->bcast.timestamp);
return false;
}
*wireaddrs = read_addresses(ctx, addresses);
tal_free(addresses);
return true;
}
/* Version which also does nodeid lookup */
static bool get_node_announcement_by_id(const tal_t *ctx,
struct daemon *daemon,
const struct node_id *node_id,
u8 rgb_color[3],
u8 alias[32],
u8 **features,
struct wireaddr **wireaddrs)
{
struct node *n = get_node(daemon->rstate, node_id);
if (!n)
return false;
return get_node_announcement(ctx, daemon, n, rgb_color, alias,
features, wireaddrs);
}
/*~Routines to handle gossip messages from peer, forwarded by subdaemons.
*-----------------------------------------------------------------------
*
* It's not the subdaemon's fault if they're malformed or invalid; so these
* all return an error packet which gets sent back to the subdaemon in that
* case.
*/
/* The routing code checks that it's basically valid, returning an
* error message for the peer or NULL. NULL means it's OK, but the
* message might be redundant, in which case scid is also NULL.
* Otherwise `scid` gives us the short_channel_id claimed by the
* message, and puts the announcemnt on an internal 'pending'
* queue. We'll send a request to lightningd to look it up, and continue
* processing in `handle_txout_reply`. */
static const u8 *handle_channel_announcement_msg(struct peer *peer,
const u8 *msg)
{
const struct short_channel_id *scid;
const u8 *err;
/* If it's OK, tells us the short_channel_id to lookup; it notes
* if this is the unknown channel the peer was looking for (in
* which case, it frees and NULLs that ptr) */
err = handle_channel_announcement(peer->daemon->rstate, msg,
peer->daemon->current_blockheight,
&scid, peer);
if (err)
return err;
else if (scid) {
/* We give them some grace period, in case we don't know about
* block yet. */
if (peer->daemon->current_blockheight == 0
|| !is_scid_depth_announceable(scid,
peer->daemon->current_blockheight)) {
tal_arr_expand(&peer->daemon->deferred_txouts, *scid);
} else {
daemon_conn_send(peer->daemon->master,
take(towire_gossipd_get_txout(NULL,
scid)));
}
}
return NULL;
}
static u8 *handle_channel_update_msg(struct peer *peer, const u8 *msg)
{
struct short_channel_id unknown_scid;
/* Hand the channel_update to the routing code */
u8 *err;
unknown_scid.u64 = 0;
err = handle_channel_update(peer->daemon->rstate, msg, peer,
&unknown_scid);
if (err) {
if (unknown_scid.u64 != 0)
query_unknown_channel(peer->daemon, peer, &unknown_scid);
return err;
}
/*~ As a nasty compromise in the spec, we only forward `channel_announce`
* once we have a `channel_update`; the channel isn't *usable* for
* routing until you have both anyway. For this reason, we might have
* just sent out our own channel_announce, so we check if it's time to
* send a node_announcement too. */
maybe_send_own_node_announce(peer->daemon);
return NULL;
}
/*~ When we compact the gossip store, all the broadcast indexs move.
* We simply offset everyone, which means in theory they could retransmit
* some, but that's a lesser evil than skipping some. */
void update_peers_broadcast_index(struct list_head *peers, u32 offset)
{
struct peer *peer, *next;
list_for_each_safe(peers, peer, next, list) {
int gs_fd;
/*~ Since store has been compacted, they need a new fd for the
* new store. We also tell them how much this is shrunk, so
* they can (approximately) tell where to start in the new store.
*/
gs_fd = gossip_store_readonly_fd(peer->daemon->rstate->gs);
if (gs_fd < 0) {
status_broken("Can't get read-only gossip store fd:"
" killing peer");
tal_free(peer);
} else {
u8 *msg = towire_gossipd_new_store_fd(NULL, offset);
daemon_conn_send(peer->dc, take(msg));
daemon_conn_send_fd(peer->dc, gs_fd);
}
}
}
/*~ For simplicity, all pings and pongs are forwarded to us here in gossipd. */
static u8 *handle_ping(struct peer *peer, const u8 *ping)
{
u8 *pong;
/* This checks the ping packet and makes a pong reply if needed; peer
* can specify it doesn't want a response, to simulate traffic. */
if (!check_ping_make_pong(NULL, ping, &pong))
return towire_errorfmt(peer, NULL, "Bad ping");
if (pong)
queue_peer_msg(peer, take(pong));
return NULL;
}
/*~ When we get a pong, we tell lightningd about it (it's probably a response
* to the `ping` JSON RPC command). */
static const u8 *handle_pong(struct peer *peer, const u8 *pong)
{
const char *err = got_pong(pong, &peer->num_pings_outstanding);
if (err)
return towire_errorfmt(peer, NULL, "%s", err);
daemon_conn_send(peer->daemon->master,
take(towire_gossipd_ping_reply(NULL, &peer->id, true,
tal_count(pong))));
return NULL;
}
/*~ This is when channeld asks us for a channel_update for a local channel.
* It does that to fill in the error field when lightningd fails an HTLC and
* sets the UPDATE bit in the error type. lightningd is too important to
* fetch this itself, so channeld does it (channeld has to talk to us for
* other things anyway, so why not?). */
static bool handle_get_local_channel_update(struct peer *peer, const u8 *msg)
{
struct short_channel_id scid;
struct local_chan *local_chan;
struct chan *chan;
const u8 *update;
struct routing_state *rstate = peer->daemon->rstate;
if (!fromwire_gossipd_get_update(msg, &scid)) {
status_broken("peer %s sent bad gossip_get_update %s",
type_to_string(tmpctx, struct node_id, &peer->id),
tal_hex(tmpctx, msg));
return false;
}
/* It's possible that the channel has just closed (though v. unlikely) */
local_chan = local_chan_map_get(&rstate->local_chan_map, &scid);
if (!local_chan) {
status_unusual("peer %s scid %s: unknown channel",
type_to_string(tmpctx, struct node_id, &peer->id),
type_to_string(tmpctx, struct short_channel_id,
&scid));
update = NULL;
goto out;
}
chan = local_chan->chan;
/* Since we're going to send it out, make sure it's up-to-date. */
refresh_local_channel(peer->daemon, local_chan, false);
/* It's possible this is zero, if we've never sent a channel_update
* for that channel. */
if (!is_halfchan_defined(&chan->half[local_chan->direction]))
update = NULL;
else
update = gossip_store_get(tmpctx, rstate->gs,
chan->half[local_chan->direction].bcast.index);
out:
status_peer_debug(&peer->id, "schanid %s: %s update",
type_to_string(tmpctx, struct short_channel_id, &scid),
update ? "got" : "no");
msg = towire_gossipd_get_update_reply(NULL, update);
daemon_conn_send(peer->dc, take(msg));
return true;
}
static u8 *handle_node_announce(struct peer *peer, const u8 *msg)
{
bool was_unknown = false;
u8 *err;
err = handle_node_announcement(peer->daemon->rstate, msg, peer,
&was_unknown);
if (was_unknown)
query_unknown_node(peer->daemon->seeker, peer);
return err;
}
static bool handle_local_channel_announcement(struct daemon *daemon,
struct peer *peer,
const u8 *msg)
{
u8 *cannouncement;
const u8 *err;
if (!fromwire_gossipd_local_channel_announcement(msg, msg,
&cannouncement)) {
status_broken("peer %s bad local_channel_announcement %s",
type_to_string(tmpctx, struct node_id, &peer->id),
tal_hex(tmpctx, msg));
return false;
}
err = handle_channel_announcement_msg(peer, cannouncement);
if (err) {
status_broken("peer %s invalid local_channel_announcement %s (%s)",
type_to_string(tmpctx, struct node_id, &peer->id),
tal_hex(tmpctx, msg),
tal_hex(tmpctx, err));
return false;
}
return true;
}
/*~ This is where the per-peer daemons send us messages. It's either forwarded
* gossip, or a request for information. We deliberately use non-overlapping
* message types so we can distinguish them. */
static struct io_plan *peer_msg_in(struct io_conn *conn,
const u8 *msg,
struct peer *peer)
{
const u8 *err;
bool ok;
/* These are messages relayed from peer */
switch ((enum peer_wire)fromwire_peektype(msg)) {
case WIRE_CHANNEL_ANNOUNCEMENT:
err = handle_channel_announcement_msg(peer, msg);
goto handled_relay;
case WIRE_CHANNEL_UPDATE:
err = handle_channel_update_msg(peer, msg);
goto handled_relay;
case WIRE_NODE_ANNOUNCEMENT:
err = handle_node_announce(peer, msg);
goto handled_relay;
case WIRE_QUERY_CHANNEL_RANGE:
err = handle_query_channel_range(peer, msg);
goto handled_relay;
case WIRE_REPLY_CHANNEL_RANGE:
err = handle_reply_channel_range(peer, msg);
goto handled_relay;
case WIRE_QUERY_SHORT_CHANNEL_IDS:
err = handle_query_short_channel_ids(peer, msg);
goto handled_relay;
case WIRE_REPLY_SHORT_CHANNEL_IDS_END:
err = handle_reply_short_channel_ids_end(peer, msg);
goto handled_relay;
case WIRE_PING:
err = handle_ping(peer, msg);
goto handled_relay;
case WIRE_PONG:
err = handle_pong(peer, msg);
goto handled_relay;
/* These are non-gossip messages (!is_msg_for_gossipd()) */
case WIRE_INIT:
case WIRE_ERROR:
case WIRE_OPEN_CHANNEL:
case WIRE_ACCEPT_CHANNEL:
case WIRE_FUNDING_CREATED:
case WIRE_FUNDING_SIGNED:
case WIRE_FUNDING_LOCKED:
case WIRE_SHUTDOWN:
case WIRE_CLOSING_SIGNED:
case WIRE_UPDATE_ADD_HTLC:
case WIRE_UPDATE_FULFILL_HTLC:
case WIRE_UPDATE_FAIL_HTLC:
case WIRE_UPDATE_FAIL_MALFORMED_HTLC:
case WIRE_COMMITMENT_SIGNED:
case WIRE_REVOKE_AND_ACK:
case WIRE_UPDATE_FEE:
case WIRE_CHANNEL_REESTABLISH:
case WIRE_ANNOUNCEMENT_SIGNATURES:
case WIRE_GOSSIP_TIMESTAMP_FILTER:
#if EXPERIMENTAL_FEATURES
case WIRE_ONION_MESSAGE:
case WIRE_TX_ADD_INPUT:
case WIRE_TX_REMOVE_INPUT:
case WIRE_TX_ADD_OUTPUT:
case WIRE_TX_REMOVE_OUTPUT:
case WIRE_TX_COMPLETE:
case WIRE_TX_SIGNATURES:
case WIRE_OPEN_CHANNEL2:
case WIRE_ACCEPT_CHANNEL2:
case WIRE_INIT_RBF:
case WIRE_BLACKLIST_PODLE:
#endif
status_broken("peer %s: relayed unexpected msg of type %s",
type_to_string(tmpctx, struct node_id, &peer->id),
peer_wire_name(fromwire_peektype(msg)));
return io_close(conn);
}
/* Must be a gossipd_peerd_wire_type asking us to do something. */
switch ((enum gossipd_peerd_wire)fromwire_peektype(msg)) {
case WIRE_GOSSIPD_GET_UPDATE:
ok = handle_get_local_channel_update(peer, msg);
goto handled_cmd;
case WIRE_GOSSIPD_LOCAL_CHANNEL_UPDATE:
ok = handle_local_channel_update(peer->daemon, &peer->id, msg);
goto handled_cmd;
case WIRE_GOSSIPD_LOCAL_CHANNEL_ANNOUNCEMENT:
ok = handle_local_channel_announcement(peer->daemon, peer, msg);
goto handled_cmd;
/* These are the ones we send, not them */
case WIRE_GOSSIPD_GET_UPDATE_REPLY:
case WIRE_GOSSIPD_NEW_STORE_FD:
break;
}
if (fromwire_peektype(msg) == WIRE_GOSSIP_STORE_PRIVATE_CHANNEL) {
ok = routing_add_private_channel(peer->daemon->rstate, peer,
msg, 0);
goto handled_cmd;
}
/* Anything else should not have been sent to us: close on it */
status_peer_broken(&peer->id, "unexpected cmd of type %i %s",
fromwire_peektype(msg),
gossipd_peerd_wire_name(fromwire_peektype(msg)));
return io_close(conn);
/* Commands should always be OK. */
handled_cmd:
if (!ok)
return io_close(conn);
goto done;
/* Forwarded messages may be bad, so we have error which the per-peer
* daemon will forward to the peer. */
handled_relay:
if (err)
queue_peer_msg(peer, take(err));
done:
return daemon_conn_read_next(conn, peer->dc);
}
/*~ This is where connectd tells us about a new peer, and we hand back an fd for
* it to send us messages via peer_msg_in above */
static struct io_plan *connectd_new_peer(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
struct peer *peer = tal(conn, struct peer);
int fds[2];
int gossip_store_fd;
struct gossip_state *gs;
if (!fromwire_gossipd_new_peer(msg, &peer->id,
&peer->gossip_queries_feature,
&peer->initial_routing_sync_feature)) {
status_broken("Bad new_peer msg from connectd: %s",
tal_hex(tmpctx, msg));
return io_close(conn);
}
gossip_store_fd = gossip_store_readonly_fd(daemon->rstate->gs);;
if (gossip_store_fd < 0) {
status_broken("Failed to get readonly store fd: %s",
strerror(errno));
daemon_conn_send(daemon->connectd,
take(towire_gossipd_new_peer_reply(NULL,
false,
NULL)));
goto done;
}
/* This can happen: we handle it gracefully, returning a `failed` msg. */
if (socketpair(AF_LOCAL, SOCK_STREAM, 0, fds) != 0) {
status_broken("Failed to create socketpair: %s",
strerror(errno));
close(gossip_store_fd);
daemon_conn_send(daemon->connectd,
take(towire_gossipd_new_peer_reply(NULL,
false,
NULL)));
goto done;
}
/* We might not have noticed old peer is dead; kill it now. */
tal_free(find_peer(daemon, &peer->id));
/* Populate the rest of the peer info. */
peer->daemon = daemon;
peer->gossip_counter = 0;
peer->scid_queries = NULL;
peer->scid_query_idx = 0;
peer->scid_query_nodes = NULL;
peer->scid_query_nodes_idx = 0;
peer->scid_query_outstanding = false;
peer->range_replies = NULL;
peer->query_channel_range_cb = NULL;
peer->num_pings_outstanding = 0;
/* We keep a list so we can find peer by id */
list_add_tail(&peer->daemon->peers, &peer->list);
tal_add_destructor(peer, destroy_peer);
/* This is the new connection: calls maybe_send_query_responses when
* nothing else to send. */
peer->dc = daemon_conn_new(daemon, fds[0],
peer_msg_in,
maybe_send_query_responses, peer);
/* Free peer if conn closed (destroy_peer closes conn if peer freed) */
tal_steal(peer->dc, peer);
/* This sends the initial timestamp filter. */
seeker_setup_peer_gossip(daemon->seeker, peer);
/* BOLT #7:
*
* A node:
* - if the `gossip_queries` feature is negotiated:
* - MUST NOT relay any gossip messages it did not generate itself,
* unless explicitly requested.
*/
if (peer->gossip_queries_feature) {
gs = NULL;
} else {
/* BOLT #7:
*
* - upon receiving an `init` message with the
* `initial_routing_sync` flag set to 1:
* - SHOULD send gossip messages for all known channels and
* nodes, as if they were just received.
* - if the `initial_routing_sync` flag is set to 0, OR if the
* initial sync was completed:
* - SHOULD resume normal operation, as specified in the
* following [Rebroadcasting](#rebroadcasting) section.
*/
gs = tal(tmpctx, struct gossip_state);
gs->timestamp_min = 0;
gs->timestamp_max = UINT32_MAX;
/* If they don't want initial sync, start at end of store */
if (!peer->initial_routing_sync_feature)
lseek(gossip_store_fd, 0, SEEK_END);
gs->next_gossip = time_mono();
}
/* Reply with success, and the new fd and gossip_state. */
daemon_conn_send(daemon->connectd,
take(towire_gossipd_new_peer_reply(NULL, true, gs)));
daemon_conn_send_fd(daemon->connectd, fds[1]);
daemon_conn_send_fd(daemon->connectd, gossip_store_fd);
done:
return daemon_conn_read_next(conn, daemon->connectd);
}
/*~ connectd can also ask us if we know any addresses for a given id. */
static struct io_plan *connectd_get_address(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
struct node_id id;
u8 rgb_color[3];
u8 alias[32];
u8 *features;
struct wireaddr *addrs;
if (!fromwire_gossipd_get_addrs(msg, &id)) {
status_broken("Bad gossipd_get_addrs msg from connectd: %s",
tal_hex(tmpctx, msg));
return io_close(conn);
}
if (!get_node_announcement_by_id(tmpctx, daemon, &id,
rgb_color, alias, &features, &addrs))
addrs = NULL;
daemon_conn_send(daemon->connectd,
take(towire_gossipd_get_addrs_reply(NULL, addrs)));
return daemon_conn_read_next(conn, daemon->connectd);
}
/*~ connectd's input handler is very simple. */
static struct io_plan *connectd_req(struct io_conn *conn,
const u8 *msg,
struct daemon *daemon)
{
enum connectd_gossipd_wire t = fromwire_peektype(msg);
switch (t) {
case WIRE_GOSSIPD_NEW_PEER:
return connectd_new_peer(conn, daemon, msg);
case WIRE_GOSSIPD_GET_ADDRS:
return connectd_get_address(conn, daemon, msg);
/* We send these, don't receive them. */
case WIRE_GOSSIPD_NEW_PEER_REPLY:
case WIRE_GOSSIPD_GET_ADDRS_REPLY:
break;
}
status_broken("Bad msg from connectd: %s",
tal_hex(tmpctx, msg));
return io_close(conn);
}
/*~ This is our 13-day timer callback for refreshing our channels. This
* was added to the spec because people abandoned their channels without
* closing them. */
static void gossip_send_keepalive_update(struct daemon *daemon,
struct local_chan *local_chan)
{
status_debug("Sending keepalive channel_update for %s/%u",
type_to_string(tmpctx, struct short_channel_id,
&local_chan->chan->scid),
local_chan->direction);
/* As a side-effect, this will create an update which matches the
* local_disabled state */
refresh_local_channel(daemon, local_chan, true);
}
/* BOLT #7:
*
* A node:
* - if a channel's oldest `channel_update`s `timestamp` is older than two weeks
* (1209600 seconds):
* - MAY prune the channel.
* - MAY ignore the channel.
*/
static void gossip_refresh_network(struct daemon *daemon)
{
u64 now = gossip_time_now(daemon->rstate).ts.tv_sec;
s64 highwater;
struct node *n;
/* Send out 1 day before deadline */
highwater = now - (GOSSIP_PRUNE_INTERVAL(daemon->rstate->dev_fast_gossip)
- GOSSIP_BEFORE_DEADLINE(daemon->rstate->dev_fast_gossip_prune));
/* Schedule next run now */
notleak(new_reltimer(&daemon->timers, daemon,
time_from_sec(GOSSIP_PRUNE_INTERVAL(daemon->rstate->dev_fast_gossip_prune)/4),
gossip_refresh_network, daemon));
/* Find myself in the network */
n = get_node(daemon->rstate, &daemon->id);
if (n) {
/* Iterate through all outgoing connection and check whether
* it's time to re-announce */
struct chan_map_iter i;
struct chan *c;
for (c = first_chan(n, &i); c; c = next_chan(n, &i)) {
struct local_chan *local_chan;
struct half_chan *hc;
local_chan = is_local_chan(daemon->rstate, c);
hc = &c->half[local_chan->direction];
if (!is_halfchan_defined(hc)) {
/* Connection is not announced yet, so don't even
* try to re-announce it */
continue;
}
if (hc->bcast.timestamp > highwater) {
/* No need to send a keepalive update message */
continue;
}
if (!is_halfchan_enabled(hc)) {
/* Only send keepalives for active connections */
continue;
}
gossip_send_keepalive_update(daemon, local_chan);
}
}
/* Now we've refreshed our channels, we can prune without clobbering
* them */
route_prune(daemon->rstate);
}
/* Disables all channels connected to our node. */
static void gossip_disable_local_channels(struct daemon *daemon)
{
struct node *local_node = get_node(daemon->rstate, &daemon->id);
struct chan_map_iter i;
struct chan *c;
/* We don't have a local_node, so we don't have any channels yet
* either */
if (!local_node)
return;
for (c = first_chan(local_node, &i); c; c = next_chan(local_node, &i))
local_disable_chan(daemon->rstate, c);
}
struct peer *random_peer(struct daemon *daemon,
bool (*check_peer)(const struct peer *peer))
{
u64 target = UINT64_MAX;
struct peer *best = NULL, *i;
/* Reservoir sampling */
list_for_each(&daemon->peers, i, list) {
u64 r;
if (!check_peer(i))
continue;
r = pseudorand_u64();
if (r <= target) {
best = i;
target = r;
}
}
return best;
}
/*~ Parse init message from lightningd: starts the daemon properly. */
static struct io_plan *gossip_init(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
u32 *dev_gossip_time;
bool dev_fast_gossip, dev_fast_gossip_prune;
u32 timestamp;
if (!fromwire_gossipd_init(daemon, msg,
&chainparams,
&daemon->our_features,
&daemon->id,
daemon->rgb,
daemon->alias,
&daemon->announcable,
&dev_gossip_time,
&dev_fast_gossip,
&dev_fast_gossip_prune)) {
master_badmsg(WIRE_GOSSIPD_INIT, msg);
}
daemon->rstate = new_routing_state(daemon,
&daemon->id,
&daemon->peers,
&daemon->timers,
take(dev_gossip_time),
dev_fast_gossip,
dev_fast_gossip_prune);
/* Load stored gossip messages, get last modified time of file */
timestamp = gossip_store_load(daemon->rstate, daemon->rstate->gs);
/* If last_timestamp was > modified time of file, reduce it.
* Usually it's capped to "now", but in the reload case it needs to
* be the gossip_store mtime. */
if (daemon->rstate->last_timestamp > timestamp)
daemon->rstate->last_timestamp = timestamp;
/* Now disable all local channels, they can't be connected yet. */
gossip_disable_local_channels(daemon);
/* If that announced channels, we can announce ourselves (options
* or addresses might have changed!) */
maybe_send_own_node_announce(daemon);
/* Start the twice- weekly refresh timer. */
notleak(new_reltimer(&daemon->timers, daemon,
time_from_sec(GOSSIP_PRUNE_INTERVAL(daemon->rstate->dev_fast_gossip_prune) / 4),
gossip_refresh_network, daemon));
/* Fire up the seeker! */
daemon->seeker = new_seeker(daemon);
return daemon_conn_read_next(conn, daemon->master);
}
/*~ lightningd can ask for a route between nodes. */
static struct io_plan *getroute_req(struct io_conn *conn, struct daemon *daemon,
const u8 *msg)
{
struct node_id *source, destination;
struct amount_msat msat;
u32 final_cltv;
/* risk factor 12.345% -> riskfactor_millionths = 12345000 */
u64 riskfactor_millionths;
u32 max_hops;
u8 *out;
struct route_hop **hops;
/* fuzz 12.345% -> fuzz_millionths = 12345000 */
u64 fuzz_millionths;
struct exclude_entry **excluded;
/* To choose between variations, we need to know how much we're
* sending (eliminates too-small channels, and also effects the fees
* we'll pay), how to trade off more locktime vs. more fees, and how
* much cltv we need a the final node to give exact values for each
* intermediate hop, as well as how much random fuzz to inject to
* avoid being too predictable.
*
* We also treat routing slightly differently if we're asking
* for a route from ourselves (the usual case): in that case,
* we don't have to consider fees on our own outgoing channels.
*/
if (!fromwire_gossipd_getroute_request(
msg, msg, &source, &destination, &msat, &riskfactor_millionths,
&final_cltv, &fuzz_millionths, &excluded, &max_hops))
master_badmsg(WIRE_GOSSIPD_GETROUTE_REQUEST, msg);
status_debug("Trying to find a route from %s to %s for %s",
source
? type_to_string(tmpctx, struct node_id, source) : "(me)",
type_to_string(tmpctx, struct node_id, &destination),
type_to_string(tmpctx, struct amount_msat, &msat));
/* routing.c does all the hard work; can return NULL. */
hops = get_route(tmpctx, daemon->rstate, source, &destination, msat,
riskfactor_millionths / 1000000.0, final_cltv,
fuzz_millionths / 1000000.0, pseudorand_u64(),
excluded, max_hops);
out = towire_gossipd_getroute_reply(NULL,
cast_const2(const struct route_hop **,
hops));
daemon_conn_send(daemon->master, take(out));
return daemon_conn_read_next(conn, daemon->master);
}
/*~ When someone asks lightningd to `listchannels`, gossipd does the work:
* marshalling the channel information for all channels into an array of
* gossip_getchannels_entry, which lightningd converts to JSON. Each channel
* is represented by two half_chan; one in each direction.
*/
static struct gossip_halfchannel_entry *hc_entry(const tal_t *ctx,
const struct chan *chan,
int idx)
{
/* Our 'struct chan' contains two nodes: they are in pubkey_cmp order
* (ie. chan->nodes[0] is the lesser pubkey) and this is the same as
* the direction bit in `channel_update`s `channel_flags`.
*
* The halfchans are arranged so that half[0] src == nodes[0], and we
* use that here. */
const struct half_chan *c = &chan->half[idx];
struct gossip_halfchannel_entry *e;
/* If we've never seen a channel_update for this direction... */
if (!is_halfchan_defined(c))
return NULL;
e = tal(ctx, struct gossip_halfchannel_entry);
e->channel_flags = c->channel_flags;
e->message_flags = c->message_flags;
e->last_update_timestamp = c->bcast.timestamp;
e->base_fee_msat = c->base_fee;
e->fee_per_millionth = c->proportional_fee;
e->delay = c->delay;
e->min = c->htlc_minimum;
e->max = c->htlc_maximum;
return e;
}
/*~ We don't keep channel features in memory; they're rarely used. So we
* remember if it exists, and load it off disk when needed. */
static u8 *get_channel_features(const tal_t *ctx,
struct gossip_store *gs,
const struct chan *chan)
{
secp256k1_ecdsa_signature sig;
u8 *features;
struct bitcoin_blkid chain_hash;
struct short_channel_id short_channel_id;
struct node_id node_id;
struct pubkey bitcoin_key;
struct amount_sat sats;
u8 *ann;
/* This is where we stash a flag to indicate it exists. */
if (!chan->half[0].any_features)
return NULL;
ann = cast_const(u8 *, gossip_store_get(tmpctx, gs, chan->bcast.index));
/* Could be a private_channel */
fromwire_gossip_store_private_channel(tmpctx, ann, &sats, &ann);
if (!fromwire_channel_announcement(ctx, ann, &sig, &sig, &sig, &sig,
&features, &chain_hash,
&short_channel_id,
&node_id, &node_id,
&bitcoin_key, &bitcoin_key))
status_failed(STATUS_FAIL_INTERNAL_ERROR,
"bad channel_announcement / local_add_channel at %u: %s",
chan->bcast.index, tal_hex(tmpctx, ann));
return features;
}
/*~ Marshal (possibly) both channel directions into entries. */
static void append_channel(struct routing_state *rstate,
const struct gossip_getchannels_entry ***entries,
const struct chan *chan,
const struct node_id *srcfilter)
{
struct gossip_getchannels_entry *e = tal(*entries, struct gossip_getchannels_entry);
e->node[0] = chan->nodes[0]->id;
e->node[1] = chan->nodes[1]->id;
e->sat = chan->sat;
e->local_disabled = is_chan_local_disabled(rstate, chan);
e->public = is_chan_public(chan);
e->short_channel_id = chan->scid;
e->features = get_channel_features(e, rstate->gs, chan);
if (!srcfilter || node_id_eq(&e->node[0], srcfilter))
e->e[0] = hc_entry(*entries, chan, 0);
else
e->e[0] = NULL;
if (!srcfilter || node_id_eq(&e->node[1], srcfilter))
e->e[1] = hc_entry(*entries, chan, 1);
else
e->e[1] = NULL;
/* We choose not to tell lightningd about channels with no updates,
* as they're unusable and can't be represented in the listchannels
* JSON output we use anyway. */
if (e->e[0] || e->e[1])
tal_arr_expand(entries, e);
}
/*~ This is where lightningd asks for all channels we know about. */
static struct io_plan *getchannels_req(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
u8 *out;
const struct gossip_getchannels_entry **entries;
struct chan *chan;
struct short_channel_id *scid, *prev;
struct node_id *source;
bool complete = true;
/* Note: scid is marked optional in gossip_wire.csv */
if (!fromwire_gossipd_getchannels_request(msg, msg, &scid, &source,
&prev))
master_badmsg(WIRE_GOSSIPD_GETCHANNELS_REQUEST, msg);
entries = tal_arr(tmpctx, const struct gossip_getchannels_entry *, 0);
/* They can ask about a particular channel by short_channel_id */
if (scid) {
chan = get_channel(daemon->rstate, scid);
if (chan)
append_channel(daemon->rstate, &entries, chan, NULL);
} else if (source) {
struct node *s = get_node(daemon->rstate, source);
if (s) {
struct chan_map_iter i;
struct chan *c;
for (c = first_chan(s, &i); c; c = next_chan(s, &i)) {
append_channel(daemon->rstate,
&entries, c, source);
}
}
} else {
u64 idx;
/* For the more general case, we just iterate through every
* short channel id, starting with previous if any (there is
* no scid 0). */
idx = prev ? prev->u64 : 0;
while ((chan = uintmap_after(&daemon->rstate->chanmap, &idx))) {
append_channel(daemon->rstate, &entries, chan, NULL);
/* Limit how many we do at once. */
if (tal_count(entries) == 4096) {
complete = false;
break;
}
}
}
out = towire_gossipd_getchannels_reply(NULL, complete, entries);
daemon_conn_send(daemon->master, take(out));
return daemon_conn_read_next(conn, daemon->master);
}
/*~ Similarly, lightningd asks us for all nodes when it gets `listnodes` */
/* We keep pointers into n, assuming it won't change. */
static void add_node_entry(const tal_t *ctx,
struct daemon *daemon,
const struct node *n,
struct gossip_getnodes_entry *e)
{
e->nodeid = n->id;
if (get_node_announcement(ctx, daemon, n,
e->color, e->alias,
&e->features,
&e->addresses)) {
e->last_timestamp = n->bcast.timestamp;
} else {
/* Timestamp on wire is an unsigned 32 bit: we use a 64-bit
* signed, so -1 means "we never received a
* channel_update". */
e->last_timestamp = -1;
}
}
/* Simply routine when they ask for `listnodes` */
static struct io_plan *getnodes(struct io_conn *conn, struct daemon *daemon,
const u8 *msg)
{
u8 *out;
struct node *n;
const struct gossip_getnodes_entry **nodes;
struct gossip_getnodes_entry *node_arr;
struct node_id *id;
if (!fromwire_gossipd_getnodes_request(tmpctx, msg, &id))
master_badmsg(WIRE_GOSSIPD_GETNODES_REQUEST, msg);
/* Format of reply is the same whether they ask for a specific node
* (0 or one responses) or all nodes (0 or more) */
if (id) {
n = get_node(daemon->rstate, id);
if (n) {
node_arr = tal_arr(tmpctx,
struct gossip_getnodes_entry,
1);
add_node_entry(node_arr, daemon, n, &node_arr[0]);
} else {
nodes = NULL;
node_arr = NULL;
}
} else {
struct node_map_iter it;
size_t i = 0;
node_arr = tal_arr(tmpctx, struct gossip_getnodes_entry,
node_map_count(daemon->rstate->nodes));
n = node_map_first(daemon->rstate->nodes, &it);
while (n != NULL) {
add_node_entry(node_arr, daemon, n, &node_arr[i++]);
n = node_map_next(daemon->rstate->nodes, &it);
}
assert(i == node_map_count(daemon->rstate->nodes));
}
/* FIXME: towire wants array of pointers. */
nodes = tal_arr(tmpctx, const struct gossip_getnodes_entry *,
tal_count(node_arr));
for (size_t i = 0; i < tal_count(node_arr); i++)
nodes[i] = &node_arr[i];
out = towire_gossipd_getnodes_reply(NULL, nodes);
daemon_conn_send(daemon->master, take(out));
return daemon_conn_read_next(conn, daemon->master);
}
/*~ We currently have a JSON command to ping a peer: it ends up here, where
* gossipd generates the actual ping and sends it like any other gossip. */
static struct io_plan *ping_req(struct io_conn *conn, struct daemon *daemon,
const u8 *msg)
{
struct node_id id;
u16 num_pong_bytes, len;
struct peer *peer;
u8 *ping;
if (!fromwire_gossipd_ping(msg, &id, &num_pong_bytes, &len))
master_badmsg(WIRE_GOSSIPD_PING, msg);
/* Even if lightningd were to check for valid ids, there's a race
* where it might vanish before we read this command; cleaner to
* handle it here with 'sent' = false. */
peer = find_peer(daemon, &id);
if (!peer) {
daemon_conn_send(daemon->master,
take(towire_gossipd_ping_reply(NULL, &id,
false, 0)));
goto out;
}
/* It should never ask for an oversize ping. */
ping = make_ping(peer, num_pong_bytes, len);
if (tal_count(ping) > 65535)
status_failed(STATUS_FAIL_MASTER_IO, "Oversize ping");
queue_peer_msg(peer, take(ping));
status_peer_debug(&peer->id, "sending ping expecting %sresponse",
num_pong_bytes >= 65532 ? "no " : "");
/* BOLT #1:
*
* A node receiving a `ping` message:
*...
* - if `num_pong_bytes` is less than 65532:
* - MUST respond by sending a `pong` message, with `byteslen` equal
* to `num_pong_bytes`.
* - otherwise (`num_pong_bytes` is **not** less than 65532):
* - MUST ignore the `ping`.
*/
if (num_pong_bytes >= 65532)
daemon_conn_send(daemon->master,
take(towire_gossipd_ping_reply(NULL, &id,
true, 0)));
else
/* We'll respond to lightningd once the pong comes in */
peer->num_pings_outstanding++;
out:
return daemon_conn_read_next(conn, daemon->master);
}
/*~ If a node has no public channels (other than the one to us), it's not
* a very useful route to tell anyone about. */
static bool node_has_public_channels(const struct node *peer,
const struct chan *exclude)
{
struct chan_map_iter i;
struct chan *c;
for (c = first_chan(peer, &i); c; c = next_chan(peer, &i)) {
if (c == exclude)
continue;
if (is_chan_public(c))
return true;
}
return false;
}
/*~ For routeboost, we offer payers a hint of what incoming channels might
* have capacity for their payment. To do this, lightningd asks for the
* information about all channels to this node; but gossipd doesn't know about
* current capacities, so lightningd selects which to use. */
static struct io_plan *get_incoming_channels(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
struct node *node;
struct route_info *public = tal_arr(tmpctx, struct route_info, 0);
struct route_info *private = tal_arr(tmpctx, struct route_info, 0);
bool *priv_deadends = tal_arr(tmpctx, bool, 0);
bool *pub_deadends = tal_arr(tmpctx, bool, 0);
if (!fromwire_gossipd_get_incoming_channels(msg))
master_badmsg(WIRE_GOSSIPD_GET_INCOMING_CHANNELS, msg);
node = get_node(daemon->rstate, &daemon->rstate->local_id);
if (node) {
struct chan_map_iter i;
struct chan *c;
for (c = first_chan(node, &i); c; c = next_chan(node, &i)) {
const struct half_chan *hc;
struct route_info ri;
bool deadend;
hc = &c->half[half_chan_to(node, c)];
if (!is_halfchan_enabled(hc))
continue;
ri.pubkey = other_node(node, c)->id;
ri.short_channel_id = c->scid;
ri.fee_base_msat = hc->base_fee;
ri.fee_proportional_millionths = hc->proportional_fee;
ri.cltv_expiry_delta = hc->delay;
deadend = !node_has_public_channels(other_node(node, c),
c);
if (is_chan_public(c)) {
tal_arr_expand(&public, ri);
tal_arr_expand(&pub_deadends, deadend);
} else {
tal_arr_expand(&private, ri);
tal_arr_expand(&priv_deadends, deadend);
}
}
}
msg = towire_gossipd_get_incoming_channels_reply(NULL,
public, pub_deadends,
private, priv_deadends);
daemon_conn_send(daemon->master, take(msg));
return daemon_conn_read_next(conn, daemon->master);
}
static struct io_plan *new_blockheight(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
if (!fromwire_gossipd_new_blockheight(msg, &daemon->current_blockheight))
master_badmsg(WIRE_GOSSIPD_NEW_BLOCKHEIGHT, msg);
/* Check if we can now send any deferred queries. */
for (size_t i = 0; i < tal_count(daemon->deferred_txouts); i++) {
const struct short_channel_id *scid
= &daemon->deferred_txouts[i];
if (!is_scid_depth_announceable(scid,
daemon->current_blockheight))
continue;
/* short_channel_id is deep enough, now ask about it. */
daemon_conn_send(daemon->master,
take(towire_gossipd_get_txout(NULL, scid)));
tal_arr_remove(&daemon->deferred_txouts, i);
i--;
}
return daemon_conn_read_next(conn, daemon->master);
}
#if DEVELOPER
/* Another testing hack */
static struct io_plan *dev_gossip_suppress(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
if (!fromwire_gossipd_dev_suppress(msg))
master_badmsg(WIRE_GOSSIPD_DEV_SUPPRESS, msg);
status_unusual("Suppressing all gossip");
dev_suppress_gossip = true;
return daemon_conn_read_next(conn, daemon->master);
}
static struct io_plan *dev_gossip_memleak(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
struct htable *memtable;
bool found_leak;
memtable = memleak_find_allocations(tmpctx, msg, msg);
/* Now delete daemon and those which it has pointers to. */
memleak_remove_region(memtable, daemon, sizeof(*daemon));
found_leak = dump_memleak(memtable);
daemon_conn_send(daemon->master,
take(towire_gossipd_dev_memleak_reply(NULL,
found_leak)));
return daemon_conn_read_next(conn, daemon->master);
}
static struct io_plan *dev_compact_store(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
bool done = gossip_store_compact(daemon->rstate->gs);
daemon_conn_send(daemon->master,
take(towire_gossipd_dev_compact_store_reply(NULL,
done)));
return daemon_conn_read_next(conn, daemon->master);
}
static struct io_plan *dev_gossip_set_time(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
u32 time;
if (!fromwire_gossipd_dev_set_time(msg, &time))
master_badmsg(WIRE_GOSSIPD_DEV_SET_TIME, msg);
if (!daemon->rstate->gossip_time)
daemon->rstate->gossip_time = tal(daemon->rstate, struct timeabs);
daemon->rstate->gossip_time->ts.tv_sec = time;
daemon->rstate->gossip_time->ts.tv_nsec = 0;
return daemon_conn_read_next(conn, daemon->master);
}
#endif /* DEVELOPER */
/*~ lightningd: so, get me the latest update for this local channel,
* so I can include it in an error message. */
static struct io_plan *get_stripped_cupdate(struct io_conn *conn,
struct daemon *daemon, const u8 *msg)
{
struct short_channel_id scid;
struct local_chan *local_chan;
const u8 *stripped_update;
if (!fromwire_gossipd_get_stripped_cupdate(msg, &scid))
master_badmsg(WIRE_GOSSIPD_GET_STRIPPED_CUPDATE, msg);
local_chan = local_chan_map_get(&daemon->rstate->local_chan_map, &scid);
if (!local_chan) {
status_debug("Failed to resolve local channel %s",
type_to_string(tmpctx, struct short_channel_id, &scid));
stripped_update = NULL;
} else {
const struct half_chan *hc;
/* Since we're going to use it, make sure it's up-to-date. */
refresh_local_channel(daemon, local_chan, false);
hc = &local_chan->chan->half[local_chan->direction];
if (is_halfchan_defined(hc)) {
const u8 *update;
update = gossip_store_get(tmpctx, daemon->rstate->gs,
hc->bcast.index);
stripped_update = tal_dup_arr(tmpctx, u8, update + 2,
tal_count(update) - 2, 0);
} else
stripped_update = NULL;
}
daemon_conn_send(daemon->master,
take(towire_gossipd_get_stripped_cupdate_reply(NULL,
stripped_update)));
return daemon_conn_read_next(conn, daemon->master);
}
/*~ We queue incoming channel_announcement pending confirmation from lightningd
* that it really is an unspent output. Here's its reply. */
static struct io_plan *handle_txout_reply(struct io_conn *conn,
struct daemon *daemon, const u8 *msg)
{
struct short_channel_id scid;
u8 *outscript;
struct amount_sat sat;
bool good;
if (!fromwire_gossipd_get_txout_reply(msg, msg, &scid, &sat, &outscript))
master_badmsg(WIRE_GOSSIPD_GET_TXOUT_REPLY, msg);
/* Outscript is NULL if it's not an unspent output */
good = handle_pending_cannouncement(daemon, daemon->rstate,
&scid, sat, outscript);
/* If we looking specifically for this, we no longer are. */
remove_unknown_scid(daemon->seeker, &scid, good);
/* Anywhere we might have announced a channel, we check if it's time to
* announce ourselves (ie. if we just announced our own first channel) */
maybe_send_own_node_announce(daemon);
return daemon_conn_read_next(conn, daemon->master);
}
/* Fix up the channel_update to include the type if it doesn't currently have
* one. See ElementsProject/lightning#1730 and lightningnetwork/lnd#1599 for the
* in-depth discussion on why we break message parsing here... */
static u8 *patch_channel_update(const tal_t *ctx, u8 *channel_update TAKES)
{
u8 *fixed;
if (channel_update != NULL &&
fromwire_peektype(channel_update) != WIRE_CHANNEL_UPDATE) {
/* This should be a channel_update, prefix with the
* WIRE_CHANNEL_UPDATE type, but isn't. Let's prefix it. */
fixed = tal_arr(ctx, u8, 0);
towire_u16(&fixed, WIRE_CHANNEL_UPDATE);
towire(&fixed, channel_update, tal_bytelen(channel_update));
if (taken(channel_update))
tal_free(channel_update);
return fixed;
} else {
return tal_dup_talarr(ctx, u8, channel_update);
}
}
/* Return NULL if the wrapped onion error message has no channel_update field,
* or return the embedded channel_update message otherwise. */
static u8 *channel_update_from_onion_error(const tal_t *ctx,
const u8 *onion_message)
{
u8 *channel_update = NULL;
struct amount_msat unused_msat;
u32 unused32;
/* Identify failcodes that have some channel_update.
*
* TODO > BOLT 1.0: Add new failcodes when updating to a
* new BOLT version. */
if (!fromwire_temporary_channel_failure(ctx,
onion_message,
&channel_update) &&
!fromwire_amount_below_minimum(ctx,
onion_message, &unused_msat,
&channel_update) &&
!fromwire_fee_insufficient(ctx,
onion_message, &unused_msat,
&channel_update) &&
!fromwire_incorrect_cltv_expiry(ctx,
onion_message, &unused32,
&channel_update) &&
!fromwire_expiry_too_soon(ctx,
onion_message,
&channel_update))
/* No channel update. */
return NULL;
return patch_channel_update(ctx, take(channel_update));
}
/*~ lightningd tells us when a payment has failed; we mark the channel (or
* node) unusable here if it's a permanent failure, and unpack any
* channel_update contained in the error. */
static struct io_plan *handle_payment_failure(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
u8 *error;
u8 *channel_update;
if (!fromwire_gossipd_payment_failure(msg, msg, &error))
master_badmsg(WIRE_GOSSIPD_PAYMENT_FAILURE, msg);
channel_update = channel_update_from_onion_error(tmpctx, error);
if (channel_update) {
status_debug("Extracted channel_update %s from onionreply %s",
tal_hex(tmpctx, channel_update),
tal_hex(tmpctx, error));
u8 *err = handle_channel_update(daemon->rstate, channel_update,
NULL, NULL);
if (err) {
status_info("extracted bad channel_update %s from onionreply %s",
sanitize_error(err, err, NULL),
error);
tal_free(err);
}
}
return daemon_conn_read_next(conn, daemon->master);
}
/*~ This is where lightningd tells us that a channel's funding transaction has
* been spent. */
static struct io_plan *handle_outpoint_spent(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
struct short_channel_id scid;
struct chan *chan;
struct routing_state *rstate = daemon->rstate;
if (!fromwire_gossipd_outpoint_spent(msg, &scid))
master_badmsg(WIRE_GOSSIPD_OUTPOINT_SPENT, msg);
chan = get_channel(rstate, &scid);
if (chan) {
status_debug(
"Deleting channel %s due to the funding outpoint being "
"spent",
type_to_string(msg, struct short_channel_id, &scid));
/* Suppress any now-obsolete updates/announcements */
add_to_txout_failures(rstate, &scid);
remove_channel_from_store(rstate, chan);
/* Freeing is sufficient since everything else is allocated off
* of the channel and this takes care of unregistering
* the channel */
free_chan(rstate, chan);
}
return daemon_conn_read_next(conn, daemon->master);
}
/*~ This is sent by lightningd when it kicks off 'closingd': we disable it
* in both directions.
*
* We'll leave it to handle_outpoint_spent to delete the channel from our view
* once the close gets confirmed. This avoids having strange states in which the
* channel is list in our peer list but won't be returned when listing public
* channels. This does not send out updates since that's triggered by the peer
* connection closing.
*/
static struct io_plan *handle_local_channel_close(struct io_conn *conn,
struct daemon *daemon,
const u8 *msg)
{
struct short_channel_id scid;
struct chan *chan;
struct routing_state *rstate = daemon->rstate;
if (!fromwire_gossipd_local_channel_close(msg, &scid))
master_badmsg(WIRE_GOSSIPD_LOCAL_CHANNEL_CLOSE, msg);
chan = get_channel(rstate, &scid);
if (chan)
local_disable_chan(rstate, chan);
return daemon_conn_read_next(conn, daemon->master);
}
/*~ This routine handles all the commands from lightningd. */
static struct io_plan *recv_req(struct io_conn *conn,
const u8 *msg,
struct daemon *daemon)
{
enum gossipd_wire t = fromwire_peektype(msg);
switch (t) {
case WIRE_GOSSIPD_INIT:
return gossip_init(conn, daemon, msg);
case WIRE_GOSSIPD_GETNODES_REQUEST:
return getnodes(conn, daemon, msg);
case WIRE_GOSSIPD_GETROUTE_REQUEST:
return getroute_req(conn, daemon, msg);
case WIRE_GOSSIPD_GETCHANNELS_REQUEST:
return getchannels_req(conn, daemon, msg);
case WIRE_GOSSIPD_GET_STRIPPED_CUPDATE:
return get_stripped_cupdate(conn, daemon, msg);
case WIRE_GOSSIPD_GET_TXOUT_REPLY:
return handle_txout_reply(conn, daemon, msg);
case WIRE_GOSSIPD_PAYMENT_FAILURE:
return handle_payment_failure(conn, daemon, msg);
case WIRE_GOSSIPD_OUTPOINT_SPENT:
return handle_outpoint_spent(conn, daemon, msg);
case WIRE_GOSSIPD_LOCAL_CHANNEL_CLOSE:
return handle_local_channel_close(conn, daemon, msg);
case WIRE_GOSSIPD_PING:
return ping_req(conn, daemon, msg);
case WIRE_GOSSIPD_GET_INCOMING_CHANNELS:
return get_incoming_channels(conn, daemon, msg);
case WIRE_GOSSIPD_NEW_BLOCKHEIGHT:
return new_blockheight(conn, daemon, msg);
#if DEVELOPER
case WIRE_GOSSIPD_DEV_SET_MAX_SCIDS_ENCODE_SIZE:
return dev_set_max_scids_encode_size(conn, daemon, msg);
case WIRE_GOSSIPD_DEV_SUPPRESS:
return dev_gossip_suppress(conn, daemon, msg);
case WIRE_GOSSIPD_DEV_MEMLEAK:
return dev_gossip_memleak(conn, daemon, msg);
case WIRE_GOSSIPD_DEV_COMPACT_STORE:
return dev_compact_store(conn, daemon, msg);
case WIRE_GOSSIPD_DEV_SET_TIME:
return dev_gossip_set_time(conn, daemon, msg);
#else
case WIRE_GOSSIPD_DEV_SET_MAX_SCIDS_ENCODE_SIZE:
case WIRE_GOSSIPD_DEV_SUPPRESS:
case WIRE_GOSSIPD_DEV_MEMLEAK:
case WIRE_GOSSIPD_DEV_COMPACT_STORE:
case WIRE_GOSSIPD_DEV_SET_TIME:
break;
#endif /* !DEVELOPER */
/* We send these, we don't receive them */
case WIRE_GOSSIPD_GETNODES_REPLY:
case WIRE_GOSSIPD_GETROUTE_REPLY:
case WIRE_GOSSIPD_GETCHANNELS_REPLY:
case WIRE_GOSSIPD_PING_REPLY:
case WIRE_GOSSIPD_GET_STRIPPED_CUPDATE_REPLY:
case WIRE_GOSSIPD_GET_INCOMING_CHANNELS_REPLY:
case WIRE_GOSSIPD_GET_TXOUT:
case WIRE_GOSSIPD_DEV_MEMLEAK_REPLY:
case WIRE_GOSSIPD_DEV_COMPACT_STORE_REPLY:
break;
}
/* Master shouldn't give bad requests. */
status_failed(STATUS_FAIL_MASTER_IO, "%i: %s",
t, tal_hex(tmpctx, msg));
}
/* This is called when lightningd closes its connection to us. We simply
* exit. */
static void master_gone(struct daemon_conn *master UNUSED)
{
daemon_shutdown();
/* Can't tell master, it's gone. */
exit(2);
}
int main(int argc, char *argv[])
{
setup_locale();
struct daemon *daemon;
subdaemon_setup(argc, argv);
daemon = tal(NULL, struct daemon);
list_head_init(&daemon->peers);
daemon->deferred_txouts = tal_arr(daemon, struct short_channel_id, 0);
daemon->node_announce_timer = NULL;
daemon->current_blockheight = 0; /* i.e. unknown */
/* Note the use of time_mono() here. That's a monotonic clock, which
* is really useful: it can only be used to measure relative events
* (there's no correspondence to time-since-Ken-grew-a-beard or
* anything), but unlike time_now(), this will never jump backwards by
* half a second and leave me wondering how my tests failed CI! */
timers_init(&daemon->timers, time_mono());
/* Our daemons always use STDIN for commands from lightningd. */
daemon->master = daemon_conn_new(daemon, STDIN_FILENO,
recv_req, NULL, daemon);
tal_add_destructor(daemon->master, master_gone);
status_setup_async(daemon->master);
/* connectd is already started, and uses this fd to ask us things. */
daemon->connectd = daemon_conn_new(daemon, CONNECTD_FD,
connectd_req, NULL, daemon);
/* This loop never exits. io_loop() only returns if a timer has
* expired, or io_break() is called, or all fds are closed. We don't
* use io_break and closing the lightningd fd calls master_gone()
* which exits. */
for (;;) {
struct timer *expired = NULL;
io_loop(&daemon->timers, &expired);
timer_expired(daemon, expired);
}
}
/*~ Note that the actual routing stuff is in routing.c; you might want to
* check that out later.
*
* But that's the last of the global daemons. We now move on to the first of
* the per-peer daemons: openingd/openingd.c.
*/