gossipd: split peer structure to clearly separate local and remote fields.

We should also go through and use consistent nomenclature on functions which are used with a local peer ("lpeer_xxx"?) and those with a remote peer ("rpeer_xxx"?) but this is minimal. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
7 years ago · bcfbc24308
1 changed files with 102 additions and 89 deletions
--- a/gossipd/gossip.c
+++ b/gossipd/gossip.c
@ -96,6 +96,30 @@ struct reaching {
 	bool succeeded;
 };

+/* Things we need when we're talking direct to the peer. */
+struct local_peer_state {
+	/* Cryptostate */
+	struct peer_crypto_state pcs;
+
+	/* File descriptor corresponding to conn. */
+	int fd;
+
+	/* Our connection (and owner) */
+	struct io_conn *conn;
+
+	/* Waiting to send_peer_with_fds to master? */
+	bool return_to_master;
+
+	/* If we're exiting due to non-gossip msg, otherwise release */
+	u8 *nongossip_msg;
+
+	/* How many pongs are we expecting? */
+	size_t num_pings_outstanding;
+
+	/* Message queue for outgoing. */
+	struct msg_queue peer_out;
+};
+
 struct peer {
 	struct daemon *daemon;

@ -111,41 +135,18 @@ struct peer {
 	/* Feature bitmaps. */
 	u8 *gfeatures, *lfeatures;

-	/* Cryptostate */
-	struct peer_crypto_state pcs;
-
-	/* File descriptor corresponding to conn. */
-	int fd;
-
-	/* Our connection (and owner) */
-	struct io_conn *conn;
-
 	/* High water mark for the staggered broadcast */
 	u64 broadcast_index;

-	/* Message queue for outgoing. */
-	struct msg_queue peer_out;
-
 	/* Is it time to continue the staggered broadcast? */
 	bool gossip_sync;

-	/* The peer owner will use this to talk to gossipd */
-	struct daemon_conn owner_conn;
-
-	/* How many pongs are we expecting? */
-	size_t num_pings_outstanding;
-
-	/* Are we the owner of the peer? */
-	bool local;
-
 	/* If we die, should we reach again? */
 	bool reach_again;

-	/* Waiting to send_peer_with_fds to master? */
-	bool return_to_master;
-
-	/* If we're exiting due to non-gossip msg, otherwise release */
-	u8 *nongossip_msg;
+	/* Only one of these is set: */
+	struct local_peer_state *local;
+	struct daemon_conn *remote;
 };

 struct addrhint {
@ -198,6 +199,20 @@ static struct addrhint *find_addrhint(struct daemon *daemon,
 	return NULL;
 }

+static struct local_peer_state *
+new_local_peer_state(struct peer *peer, const struct crypto_state *cs)
+{
+	struct local_peer_state *lps = tal(peer, struct local_peer_state);
+
+	init_peer_crypto_state(peer, &lps->pcs);
+	lps->pcs.cs = *cs;
+	lps->return_to_master = false;
+	lps->num_pings_outstanding = 0;
+	msg_queue_init(&lps->peer_out, peer);
+
+	return lps;
+}
+
 static struct peer *new_peer(const tal_t *ctx,
 			     struct daemon *daemon,
 			     const struct pubkey *their_id,
@ -206,17 +221,13 @@ static struct peer *new_peer(const tal_t *ctx,
 {
 	struct peer *peer = tal(ctx, struct peer);

-	init_peer_crypto_state(peer, &peer->pcs);
-	peer->pcs.cs = *cs;
 	peer->id = *their_id;
 	peer->addr = *addr;
 	peer->daemon = daemon;
-	peer->local = true;
+	peer->local = new_local_peer_state(peer, cs);
+	peer->remote = NULL;
 	peer->reach_again = false;
-	peer->return_to_master = false;
-	peer->num_pings_outstanding = 0;
 	peer->broadcast_index = 0;
-	msg_queue_init(&peer->peer_out, peer);

 	return peer;
 }
@ -277,7 +288,7 @@ static void peer_error(struct peer *peer, const char *fmt, ...)

 	/* Send error: we'll close after writing this. */
 	va_start(ap, fmt);
-	msg_enqueue(&peer->peer_out,
+	msg_enqueue(&peer->local->peer_out,
 		    take(towire_errorfmtv(peer, NULL, fmt, ap)));
 	va_end(ap);
 }
@ -320,7 +331,7 @@ static struct io_plan *peer_init_received(struct io_conn *conn,

 	/* We will not have anything queued, since we're not duplex. */
 	msg = towire_gossip_peer_connected(peer, &peer->id, &peer->addr,
-					   &peer->pcs.cs,
+					   &peer->local->pcs.cs,
 					   peer->gfeatures, peer->lfeatures);
 	if (!send_peer_with_fds(peer, msg))
 		return io_close(conn);
@ -341,7 +352,7 @@ static struct io_plan *read_init(struct io_conn *conn, struct peer *peer)
 	 * Each node MUST wait to receive `init` before sending any other
 	 * messages.
 	 */
-	return peer_read_message(conn, &peer->pcs, peer_init_received);
+	return peer_read_message(conn, &peer->local->pcs, peer_init_received);
 }

 /* This creates a temporary peer which is not in the list and is owner
@ -356,7 +367,7 @@ static struct io_plan *init_new_peer(struct io_conn *conn,
 	struct peer *peer = new_peer(conn, daemon, their_id, addr, cs);
 	u8 *initmsg;

-	peer->fd = io_conn_fd(conn);
+	peer->local->fd = io_conn_fd(conn);

 	/* BOLT #1:
 	 *
@ -365,7 +376,8 @@ static struct io_plan *init_new_peer(struct io_conn *conn,
 	 */
 	initmsg = towire_init(peer,
 			      daemon->globalfeatures, daemon->localfeatures);
-	return peer_write_message(conn, &peer->pcs, take(initmsg), read_init);
+	return peer_write_message(conn, &peer->local->pcs,
+				  take(initmsg), read_init);
 }

 static struct io_plan *owner_msg_in(struct io_conn *conn,
@ -458,7 +470,7 @@ static void handle_ping(struct peer *peer, u8 *ping)
 	}

 	if (pong)
-		msg_enqueue(&peer->peer_out, take(pong));
+		msg_enqueue(&peer->local->peer_out, take(pong));
 }

 static void handle_pong(struct peer *peer, const u8 *pong)
@ -471,12 +483,12 @@ static void handle_pong(struct peer *peer, const u8 *pong)
 		return;
 	}

-	if (!peer->num_pings_outstanding) {
+	if (!peer->local->num_pings_outstanding) {
 		peer_error(peer, "Unexpected pong");
 		return;
 	}

-	peer->num_pings_outstanding--;
+	peer->local->num_pings_outstanding--;
 	daemon_conn_send(&peer->daemon->master,
 			 take(towire_gossip_ping_reply(pong, true,
 						       tal_len(pong))));
@ -493,24 +505,23 @@ static void fail_release(struct peer *peer)
 static struct io_plan *ready_for_master(struct io_conn *conn, struct peer *peer)
 {
 	u8 *msg;
-	if (peer->nongossip_msg)
+	if (peer->local->nongossip_msg)
 		msg = towire_gossip_peer_nongossip(peer, &peer->id,
 						   &peer->addr,
-						   &peer->pcs.cs,
+						   &peer->local->pcs.cs,
 						   peer->gfeatures,
 						   peer->lfeatures,
-						   peer->nongossip_msg);
+						   peer->local->nongossip_msg);
 	else
 		msg = towire_gossipctl_release_peer_reply(peer,
 							  &peer->addr,
-							  &peer->pcs.cs,
+							  &peer->local->pcs.cs,
 							  peer->gfeatures,
 							  peer->lfeatures);

 	if (send_peer_with_fds(peer, take(msg))) {
 		/* In case we set this earlier. */
 		tal_del_destructor(peer, fail_release);
-		peer->return_to_master = false;
 		return io_close_taken_fd(conn);
 	} else
 		return io_close(conn);
@ -523,14 +534,14 @@ static struct io_plan *peer_msgin(struct io_conn *conn,
 * pass up to master */
 static struct io_plan *peer_next_in(struct io_conn *conn, struct peer *peer)
 {
-	if (peer->return_to_master) {
-		assert(!peer_in_started(conn, &peer->pcs));
-		if (!peer_out_started(conn, &peer->pcs))
+	if (peer->local->return_to_master) {
+		assert(!peer_in_started(conn, &peer->local->pcs));
+		if (!peer_out_started(conn, &peer->local->pcs))
 			return ready_for_master(conn, peer);
 		return io_wait(conn, peer, peer_next_in, peer);
 	}

-	return peer_read_message(conn, &peer->pcs, peer_msgin);
+	return peer_read_message(conn, &peer->local->pcs, peer_msgin);
 }

 static struct io_plan *peer_msgin(struct io_conn *conn,
@ -577,8 +588,8 @@ static struct io_plan *peer_msgin(struct io_conn *conn,
 	case WIRE_REVOKE_AND_ACK:
 	case WIRE_INIT:
 		/* Not our place to handle this, so we punt */
-		peer->return_to_master = true;
-		peer->nongossip_msg = tal_steal(peer, msg);
+		peer->local->return_to_master = true;
+		peer->local->nongossip_msg = tal_steal(peer, msg);

 		/* This will wait. */
 		return peer_next_in(conn, peer);
@ -609,28 +620,32 @@ static void wake_pkt_out(struct peer *peer)
 	new_reltimer(&peer->daemon->timers, peer,
 		     time_from_msec(peer->daemon->broadcast_interval),
 		     wake_pkt_out, peer);
-	/* Notify the peer-write loop */
-	msg_wake(&peer->peer_out);
-	/* Notify the daemon_conn-write loop */
-	msg_wake(&peer->owner_conn.out);
+
+	if (peer->local)
+		/* Notify the peer-write loop */
+		msg_wake(&peer->local->peer_out);
+	else
+		/* Notify the daemon_conn-write loop */
+		msg_wake(&peer->remote->out);
 }

 static struct io_plan *peer_pkt_out(struct io_conn *conn, struct peer *peer)
 {
 	/* First priority is queued packets, if any */
-	const u8 *out = msg_dequeue(&peer->peer_out);
+	const u8 *out = msg_dequeue(&peer->local->peer_out);
 	if (out) {
 		if (is_all_channel_error(out))
-			return peer_write_message(conn, &peer->pcs, take(out),
+			return peer_write_message(conn, &peer->local->pcs,
+						  take(out),
 						  peer_close_after_error);
-		return peer_write_message(conn, &peer->pcs, take(out),
+		return peer_write_message(conn, &peer->local->pcs, take(out),
 					  peer_pkt_out);
 	}

 	/* Do we want to send this peer to the master daemon? */
-	if (peer->return_to_master) {
-		assert(!peer_out_started(conn, &peer->pcs));
-		if (!peer_in_started(conn, &peer->pcs))
+	if (peer->local->return_to_master) {
+		assert(!peer_out_started(conn, &peer->local->pcs));
+		if (!peer_in_started(conn, &peer->local->pcs))
 			return ready_for_master(conn, peer);
 		return io_out_wait(conn, peer, peer_pkt_out, peer);
 	}
@ -643,14 +658,14 @@ static struct io_plan *peer_pkt_out(struct io_conn *conn, struct peer *peer)
 					      &peer->broadcast_index);

 		if (next)
-			return peer_write_message(conn, &peer->pcs,
+			return peer_write_message(conn, &peer->local->pcs,
 						  next->payload, peer_pkt_out);

 		/* Gossip is drained.  Wait for next timer. */
 		peer->gossip_sync = false;
 	}

-	return msg_queue_wait(conn, &peer->peer_out, peer_pkt_out, peer);
+	return msg_queue_wait(conn, &peer->local->peer_out, peer_pkt_out, peer);
 }

 /* Now we're a fully-fledged peer. */
@ -704,7 +719,7 @@ static void handle_get_update(struct peer *peer, const u8 *msg)

 reply:
 	msg = towire_gossip_get_update_reply(msg, update);
-	daemon_conn_send(&peer->owner_conn, take(msg));
+	daemon_conn_send(peer->remote, take(msg));
 }

 /**
@ -714,7 +729,7 @@ reply:
 static struct io_plan *owner_msg_in(struct io_conn *conn,
 				    struct daemon_conn *dc)
 {
-	struct peer *peer = container_of(dc, struct peer, owner_conn);
+	struct peer *peer = dc->ctx;
 	u8 *msg = dc->msg_in;

 	int type = fromwire_peektype(msg);
@ -744,6 +759,7 @@ static void forget_peer(struct io_conn *conn, struct daemon_conn *dc)
 static bool send_peer_with_fds(struct peer *peer, const u8 *msg)
 {
 	int fds[2];
+	int peer_fd = peer->local->fd;

 	if (socketpair(AF_LOCAL, SOCK_STREAM, 0, fds) != 0) {
 		status_trace("Failed to create socketpair: %s",
@ -755,21 +771,19 @@ static bool send_peer_with_fds(struct peer *peer, const u8 *msg)
 	}

 	/* Now we talk to socket to get to peer's owner daemon. */
-	peer->local = false;
-
-	daemon_conn_init(peer, &peer->owner_conn, fds[0],
+	peer->local = tal_free(peer->local);
+	peer->remote = tal(peer, struct daemon_conn);
+	daemon_conn_init(peer, peer->remote, fds[0],
 			 owner_msg_in, forget_peer);
-	peer->owner_conn.msg_queue_cleared_cb = nonlocal_dump_gossip;
+	peer->remote->msg_queue_cleared_cb = nonlocal_dump_gossip;

 	/* Peer stays around, even though caller will close conn. */
 	tal_steal(peer->daemon, peer);

 	daemon_conn_send(&peer->daemon->master, msg);
-	daemon_conn_send_fd(&peer->daemon->master, peer->fd);
+	daemon_conn_send_fd(&peer->daemon->master, peer_fd);
 	daemon_conn_send_fd(&peer->daemon->master, fds[1]);

-	/* Don't get confused: we can't use this any more. */
-	peer->fd = -1;
 	return true;
 }

@ -781,19 +795,17 @@ static bool send_peer_with_fds(struct peer *peer, const u8 *msg)
 static struct io_plan *nonlocal_dump_gossip(struct io_conn *conn, struct daemon_conn *dc)
 {
 	struct queued_message *next;
-	struct peer *peer = container_of(dc, struct peer, owner_conn);
+	struct peer *peer = dc->ctx;


 	/* Make sure we are not connected directly */
-	if (peer->local)
-		return msg_queue_wait(conn, &peer->owner_conn.out,
-				      daemon_conn_write_next, dc);
+	assert(!peer->local);

 	next = next_broadcast_message(peer->daemon->rstate->broadcasts,
 				      &peer->broadcast_index);

 	if (!next) {
-		return msg_queue_wait(conn, &peer->owner_conn.out,
+		return msg_queue_wait(conn, &peer->remote->out,
 				      daemon_conn_write_next, dc);
 	} else {
 		return io_write_wire(conn, next->payload, nonlocal_dump_gossip, dc);
@ -802,14 +814,15 @@ static struct io_plan *nonlocal_dump_gossip(struct io_conn *conn, struct daemon_

 static struct io_plan *new_peer_got_fd(struct io_conn *conn, struct peer *peer)
 {
-	peer->conn = io_new_conn(conn, peer->fd, peer_start_gossip, peer);
-	if (!peer->conn) {
+	peer->local->conn = io_new_conn(conn, peer->local->fd,
+					peer_start_gossip, peer);
+	if (!peer->local->conn) {
 		status_trace("Could not create connection for peer: %s",
 			     strerror(errno));
 		tal_free(peer);
 	} else {
 		/* If conn dies, we forget peer. */
-		tal_steal(peer->conn, peer);
+		tal_steal(peer->local->conn, peer);
 	}
 	return daemon_conn_read_next(conn, &peer->daemon->master);
 }
@ -860,9 +873,9 @@ static struct io_plan *handle_peer(struct io_conn *conn, struct daemon *daemon,
 	peer_finalized(peer);

 	if (tal_len(inner_msg))
-		msg_enqueue(&peer->peer_out, take(inner_msg));
+		msg_enqueue(&peer->local->peer_out, take(inner_msg));

-	return io_recv_fd(conn, &peer->fd, new_peer_got_fd, peer);
+	return io_recv_fd(conn, &peer->local->fd, new_peer_got_fd, peer);
 }

 static struct io_plan *release_peer(struct io_conn *conn, struct daemon *daemon,
@ -875,21 +888,21 @@ static struct io_plan *release_peer(struct io_conn *conn, struct daemon *daemon,
 		master_badmsg(WIRE_GOSSIPCTL_RELEASE_PEER, msg);

 	peer = find_peer(daemon, &id);
-	if (!peer || !peer->local || peer->return_to_master) {
+	if (!peer || !peer->local || peer->local->return_to_master) {
 		/* This can happen with dying peers, or reconnect */
 		status_trace("release_peer: peer %s %s",
 			     type_to_string(trc, struct pubkey, &id),
 			     !peer ? "not found"
-			     : peer->return_to_master ? "already releasing"
+			     : peer->local ? "already releasing"
 			     : "not local");
 		msg = towire_gossipctl_release_peer_replyfail(msg);
 		daemon_conn_send(&daemon->master, take(msg));
 	} else {
-		peer->return_to_master = true;
-		peer->nongossip_msg = NULL;
+		peer->local->return_to_master = true;
+		peer->local->nongossip_msg = NULL;

 		/* Wake output, in case it's idle. */
-		msg_wake(&peer->peer_out);
+		msg_wake(&peer->local->peer_out);
 	}
 	return daemon_conn_read_next(conn, &daemon->master);
 }
@ -1002,7 +1015,7 @@ static struct io_plan *ping_req(struct io_conn *conn, struct daemon *daemon,
 	if (tal_len(ping) > 65535)
 		status_failed(STATUS_FAIL_MASTER_IO, "Oversize ping");

-	msg_enqueue(&peer->peer_out, take(ping));
+	msg_enqueue(&peer->local->peer_out, take(ping));
 	status_trace("sending ping expecting %sresponse",
 		     num_pong_bytes >= 65532 ? "no " : "");

@ -1016,7 +1029,7 @@ static struct io_plan *ping_req(struct io_conn *conn, struct daemon *daemon,
 		daemon_conn_send(&daemon->master,
 				 take(towire_gossip_ping_reply(peer, true, 0)));
 	else
-		peer->num_pings_outstanding++;
+		peer->local->num_pings_outstanding++;

 out:
 	return daemon_conn_read_next(conn, &daemon->master);