common/gossmap: use u64 for all offsets.

Since we don't compact the gossmap on the fly (FIXME!) we can
easily surpass 4GB in the gossmap, and 32 bit offsets are not
sufficient.

I'm a bit surprised we don't crash immediately, but we've definitely
seen issues.

Changelog-Fixed: gossipd: crash errors with large gossip_store (>4MB) growth on longer-running nodes.
Signed-off-by: Rusty Russell <[email protected]>

Author: rustyrussell

common/gossmap.c

@@ -13,6 +13,7 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <gossipd/gossip_store_wiregen.h>
+#include <inttypes.h>
 #include <sys/mman.h>
 #include <unistd.h>
 #include <wire/peer_wire.h>
@@ -60,7 +61,7 @@ struct gossmap {
 	/* The memory map of the file: u8 for arithmetic portability */
 	u8 *mmap;
 	/* map_end is where we read to so far, map_size is total size */
-	size_t map_end, map_size;
+	u64 map_end, map_size;
 
 	/* Map of node id -> node */
 	struct nodeidx_htable *nodes;
@@ -93,18 +94,18 @@ struct gossmap {
 			     void *cb_arg);
 	bool (*unknown_record)(struct gossmap *map,
 			       int type,
-			       size_t off,
+			       u64 off,
 			       size_t msglen,
 			       void *cb_arg);
 	void *cb_arg;
 };
 
 /* Accessors for the gossmap */
-static void map_copy(const struct gossmap *map, size_t offset,
+static void map_copy(const struct gossmap *map, u64 offset,
 		     void *dst, size_t len)
 {
 	if (offset >= map->map_size) {
-		size_t localoff = offset - map->map_size;
+		u64 localoff = offset - map->map_size;
 		assert(localoff + len <= tal_bytelen(map->local));
 		memcpy(dst, map->local + localoff, len);
 	} else {
@@ -119,35 +120,35 @@ static void map_copy(const struct gossmap *map, size_t offset,
 	}
 }
 
-static u8 map_u8(const struct gossmap *map, size_t offset)
+static u8 map_u8(const struct gossmap *map, u64 offset)
 {
 	u8 u8;
 	map_copy(map, offset, &u8, sizeof(u8));
 	return u8;
 }
 
-static u16 map_be16(const struct gossmap *map, size_t offset)
+static u16 map_be16(const struct gossmap *map, u64 offset)
 {
 	be16 be16;
 	map_copy(map, offset, &be16, sizeof(be16));
 	return be16_to_cpu(be16);
 }
 
-static u32 map_be32(const struct gossmap *map, size_t offset)
+static u32 map_be32(const struct gossmap *map, u64 offset)
 {
 	be32 be32;
 	map_copy(map, offset, &be32, sizeof(be32));
 	return be32_to_cpu(be32);
 }
 
-static u64 map_be64(const struct gossmap *map, size_t offset)
+static u64 map_be64(const struct gossmap *map, u64 offset)
 {
 	be64 be64;
 	map_copy(map, offset, &be64, sizeof(be64));
 	return be64_to_cpu(be64);
 }
 
-static void map_nodeid(const struct gossmap *map, size_t offset,
+static void map_nodeid(const struct gossmap *map, u64 offset,
 		       struct node_id *id)
 {
 	map_copy(map, offset, id, sizeof(*id));
@@ -156,7 +157,7 @@ static void map_nodeid(const struct gossmap *map, size_t offset,
 /* Returns optional or compulsory feature if set, otherwise -1 */
 static int map_feature_test(const struct gossmap *map,
 			    int compulsory_bit,
-			    size_t offset, size_t len)
+			    u64 offset, size_t len)
 {
 	size_t bytenum = compulsory_bit / 8;
 	u8 bits;
@@ -373,8 +374,8 @@ static struct gossmap_chan *next_free_chan(struct gossmap *map)
 }
 
 static struct gossmap_chan *new_channel(struct gossmap *map,
-					u32 cannounce_off,
-					u32 plus_scid_off,
+					u64 cannounce_off,
+					u64 plus_scid_off,
 					u32 n1idx, u32 n2idx)
 {
 	struct gossmap_chan *chan = next_free_chan(map);
@@ -444,13 +445,13 @@ void gossmap_remove_node(struct gossmap *map, struct gossmap_node *node)
  *     * [`point`:`node_id_2`]
  */
 static struct gossmap_chan *add_channel(struct gossmap *map,
-					size_t cannounce_off,
+					u64 cannounce_off,
 					size_t msglen)
 {
 	/* Note that first two bytes are message type */
-	const size_t feature_len_off = 2 + (64 + 64 + 64 + 64);
+	const u64 feature_len_off = 2 + (64 + 64 + 64 + 64);
 	size_t feature_len;
-	size_t plus_scid_off;
+	u64 plus_scid_off;
 	struct short_channel_id scid;
 	struct node_id node_id[2];
 	struct gossmap_node *n[2];
@@ -468,7 +469,7 @@ static struct gossmap_chan *add_channel(struct gossmap *map,
 	chan = gossmap_find_chan(map, &scid);
 	if (chan) {
 		/* FIXME: Report this better! */
-		warnx("gossmap: redundant channel_announce for %s, offsets %u and %zu!",
+		warnx("gossmap: redundant channel_announce for %s, offsets %"PRIu64" and %"PRIu64"!",
 		      fmt_short_channel_id(tmpctx, scid),
 		      chan->cann_off, cannounce_off);
 		return NULL;
@@ -522,17 +523,17 @@ static struct gossmap_chan *add_channel(struct gossmap *map,
  *     * [`u32`:`fee_proportional_millionths`]
  *     * [`u64`:`htlc_maximum_msat`]
  */
-static void update_channel(struct gossmap *map, size_t cupdate_off)
+static void update_channel(struct gossmap *map, u64 cupdate_off)
 {
 	/* Note that first two bytes are message type */
-	const size_t scid_off = cupdate_off + 2 + (64 + 32);
-	const size_t message_flags_off = scid_off + 8 + 4;
-	const size_t channel_flags_off = message_flags_off + 1;
-	const size_t cltv_expiry_delta_off = channel_flags_off + 1;
-	const size_t htlc_minimum_off = cltv_expiry_delta_off + 2;
-	const size_t fee_base_off = htlc_minimum_off + 8;
-	const size_t fee_prop_off = fee_base_off + 4;
-	const size_t htlc_maximum_off = fee_prop_off + 4;
+	const u64 scid_off = cupdate_off + 2 + (64 + 32);
+	const u64 message_flags_off = scid_off + 8 + 4;
+	const u64 channel_flags_off = message_flags_off + 1;
+	const u64 cltv_expiry_delta_off = channel_flags_off + 1;
+	const u64 htlc_minimum_off = cltv_expiry_delta_off + 2;
+	const u64 fee_base_off = htlc_minimum_off + 8;
+	const u64 fee_prop_off = fee_base_off + 4;
+	const u64 htlc_maximum_off = fee_prop_off + 4;
 	struct short_channel_id_dir scidd;
 	struct gossmap_chan *chan;
 	struct half_chan hc;
@@ -578,7 +579,7 @@ static void update_channel(struct gossmap *map, size_t cupdate_off)
 	chan->cupdate_off[chanflags & 1] = cupdate_off;
 }
 
-static void remove_channel_by_deletemsg(struct gossmap *map, size_t del_off)
+static void remove_channel_by_deletemsg(struct gossmap *map, u64 del_off)
 {
 	struct short_channel_id scid;
 	struct gossmap_chan *chan;
@@ -616,9 +617,9 @@ struct short_channel_id gossmap_chan_scid(const struct gossmap *map,
  *    * [`u16`:`addrlen`]
  *    * [`addrlen*byte`:`addresses`]
  */
-static void node_announcement(struct gossmap *map, size_t nann_off)
+static void node_announcement(struct gossmap *map, u64 nann_off)
 {
-	const size_t feature_len_off = 2 + 64;
+	const u64 feature_len_off = 2 + 64;
 	size_t feature_len;
 	struct gossmap_node *n;
 	struct node_id id;
@@ -629,7 +630,7 @@ static void node_announcement(struct gossmap *map, size_t nann_off)
 		n->nann_off = nann_off;
 }
 
-static bool reopen_store(struct gossmap *map, size_t ended_off)
+static bool reopen_store(struct gossmap *map, u64 ended_off)
 {
 	int fd;
 
@@ -659,7 +660,7 @@ static bool map_catchup(struct gossmap *map, bool *changed)
 	for (; map->map_end + sizeof(struct gossip_hdr) < map->map_size;
 	     map->map_end += reclen) {
 		struct gossip_hdr ghdr;
-		size_t off;
+		u64 off;
 		u16 type, flags;
 
 		map_copy(map, map->map_end, &ghdr, sizeof(ghdr));
@@ -764,18 +765,18 @@ static void destroy_map(struct gossmap *map)
 struct localmod {
 	struct short_channel_id scid;
 	/* If this is an entirely-local channel, here's its offset.
-	 * Otherwise, 0xFFFFFFFF. */
-	u32 local_off;
+	 * Otherwise, 0xFFFFFFFFFFFFFFFF. */
+	u64 local_off;
 
 	/* Are updates in either direction set? */
 	bool updates_set[2];
 	/* hc[n] defined if updates_set[n]. */
 	struct half_chan hc[2];
-	/* orig[n] defined if updates_set[n] and local_off == 0xFFFFFFFF */
+	/* orig[n] defined if updates_set[n] and local_off == 0xFFFFFFFFFFFFFFFF */
 	struct half_chan orig[2];
 
 	/* Original update offsets */
-	u32 orig_cupdate_off[2];
+	u64 orig_cupdate_off[2];
 };
 
 struct gossmap_localmods {
@@ -822,7 +823,7 @@ bool gossmap_local_addchan(struct gossmap_localmods *localmods,
 {
 	be16 be16;
 	be64 be64;
-	size_t off;
+	u64 off;
 	struct localmod mod;
 
 	/* Don't create duplicate channels. */
@@ -907,7 +908,7 @@ bool gossmap_local_updatechan(struct gossmap_localmods *localmods,
 		mod = &localmods->mods[nmods];
 		mod->scid = scid;
 		mod->updates_set[0] = mod->updates_set[1] = false;
-		mod->local_off = 0xFFFFFFFF;
+		mod->local_off = 0xFFFFFFFFFFFFFFFF;
 	}
 
 	assert(dir == 0 || dir == 1);
@@ -949,7 +950,7 @@ void gossmap_apply_localmods(struct gossmap *map,
 		chan = gossmap_find_chan(map, &mod->scid);
 		/* If it doesn't exist, are we supposed to create a local one? */
 		if (!chan) {
-			if (mod->local_off == 0xFFFFFFFF)
+			if (mod->local_off == 0xFFFFFFFFFFFFFFFF)
 				continue;
 
 			/* Create new channel, pointing into local. */
@@ -1090,7 +1091,7 @@ struct gossmap *gossmap_load_fd_(const tal_t *ctx, int fd,
 						      void *cb_arg),
 				 bool (*unknown_record)(struct gossmap *map,
 							int type,
-							size_t off,
+							u64 off,
 							size_t msglen,
 							void *cb_arg),
 				 void *cb_arg)
@@ -1130,7 +1131,7 @@ bool gossmap_chan_is_dying(const struct gossmap *map,
 			   const struct gossmap_chan *c)
 {
 	struct gossip_hdr ghdr;
-	size_t off;
+	u64 off;
 
 	/* FIXME: put this flag in plus_scid_off instead? */
 	off = c->cann_off - sizeof(ghdr);
@@ -1144,7 +1145,7 @@ bool gossmap_chan_get_capacity(const struct gossmap *map,
 			       struct amount_sat *amount)
 {
 	struct gossip_hdr ghdr;
-	size_t off;
+	u64 off;
 	u16 type;
 
 	/* Fail for local channels */
@@ -1319,7 +1320,7 @@ int gossmap_chan_get_feature(const struct gossmap *map,
 			     int fbit)
 {
 	/* Note that first two bytes are message type */
-	const size_t feature_len_off = 2 + (64 + 64 + 64 + 64);
+	const u64 feature_len_off = 2 + (64 + 64 + 64 + 64);
 	size_t feature_len;
 
 	feature_len = map_be16(map, c->cann_off + feature_len_off);
@@ -1334,7 +1335,7 @@ u8 *gossmap_chan_get_features(const tal_t *ctx,
 {
 	u8 *ret;
 	/* Note that first two bytes are message type */
-	const size_t feature_len_off = 2 + (64 + 64 + 64 + 64);
+	const u64 feature_len_off = 2 + (64 + 64 + 64 + 64);
 	size_t feature_len;
 
 	feature_len = map_be16(map, c->cann_off + feature_len_off);
@@ -1391,15 +1392,15 @@ void gossmap_chan_get_update_details(const struct gossmap *map,
 				     struct amount_msat *htlc_maximum_msat)
 {
 	/* Note that first two bytes are message type */
-	const size_t scid_off = chan->cupdate_off[dir] + 2 + (64 + 32);
-	const size_t timestamp_off = scid_off + 8;
-	const size_t message_flags_off = timestamp_off + 4;
-	const size_t channel_flags_off = message_flags_off + 1;
-	const size_t cltv_expiry_delta_off = channel_flags_off + 1;
-	const size_t htlc_minimum_off = cltv_expiry_delta_off + 2;
-	const size_t fee_base_off = htlc_minimum_off + 8;
-	const size_t fee_prop_off = fee_base_off + 4;
-	const size_t htlc_maximum_off = fee_prop_off + 4;
+	const u64 scid_off = chan->cupdate_off[dir] + 2 + (64 + 32);
+	const u64 timestamp_off = scid_off + 8;
+	const u64 message_flags_off = timestamp_off + 4;
+	const u64 channel_flags_off = message_flags_off + 1;
+	const u64 cltv_expiry_delta_off = channel_flags_off + 1;
+	const u64 htlc_minimum_off = cltv_expiry_delta_off + 2;
+	const u64 fee_base_off = htlc_minimum_off + 8;
+	const u64 fee_prop_off = fee_base_off + 4;
+	const u64 htlc_maximum_off = fee_prop_off + 4;
 
 	assert(gossmap_chan_set(chan, dir));
 	/* Not allowed on local updates! */
@@ -1440,7 +1441,7 @@ int gossmap_node_get_feature(const struct gossmap *map,
 			     const struct gossmap_node *n,
 			     int fbit)
 {
-	const size_t feature_len_off = 2 + 64;
+	const u64 feature_len_off = 2 + 64;
 	size_t feature_len;
 
 	if (n->nann_off == 0)
@@ -1458,7 +1459,7 @@ u8 *gossmap_node_get_features(const tal_t *ctx,
 {
 	u8 *ret;
 	/* Note that first two bytes are message type */
-	const size_t feature_len_off = 2 + 64;
+	const u64 feature_len_off = 2 + 64;
 	size_t feature_len;
 
 	if (n->nann_off == 0)
@@ -1491,7 +1492,7 @@ bool gossmap_scidd_pubkey(struct gossmap *gossmap,
 	return sciddir_or_pubkey_from_node_id(sciddpk, &id);
 }
 
-size_t gossmap_lengths(const struct gossmap *map, size_t *total)
+u64 gossmap_lengths(const struct gossmap *map, u64 *total)
 {
 	*total = map->map_size;
 	return map->map_end;
@@ -1549,7 +1550,7 @@ const void *gossmap_stream_next(const tal_t *ctx,
 
 	while (iter->offset + sizeof(h.u.type) <= map->map_size) {
 		void *ret;
-		size_t len;
+		u64 len;
 
 		map_copy(map, iter->offset, &h, sizeof(h.u.type));
 

common/gossmap.h

@@ -12,18 +12,18 @@ struct sciddir_or_pubkey;
 
 struct gossmap_node {
 	/* Offset in memory map for node_announce, or 0. */
-	u32 nann_off;
+	u64 nann_off;
 	u32 num_chans;
 	u32 *chan_idxs;
 };
 
 struct gossmap_chan {
-	u32 cann_off;
-	/* Technically redundant, but we have a hole anyway: from cann_off */
-	u32 plus_scid_off;
+	u64 cann_off;
+	/* FIXME: Technically redundant */
+	u64 plus_scid_off;
 	/* Offsets of cupdates (0 if missing).  Logically inside half_chan,
 	 * but that would add padding. */
-	u32 cupdate_off[2];
+	u64 cupdate_off[2];
 	/* two nodes we connect (lesser idx first) */
 	struct half_chan {
 		/* Top bit indicates it's enabled */
@@ -57,7 +57,7 @@ struct gossmap *gossmap_load(const tal_t *ctx, const char *filename,
 			 typesafe_cb_preargs(bool, void *, (unknown_record), (cbarg), \
 					     struct gossmap *,		\
 					     int type,			\
-					     size_t off,		\
+					     u64 off,			\
 					     size_t msglen),		\
 			 (cbarg))
 
@@ -70,7 +70,7 @@ struct gossmap *gossmap_load_fd_(const tal_t *ctx, int fd,
 						      void *cb_arg),
 				 bool (*unknown_record)(struct gossmap *map,
 							int type,
-							size_t off,
+							u64 off,
 							size_t msglen,
 							void *cb_arg),
 				 void *cb_arg);
@@ -296,7 +296,7 @@ void gossmap_iter_fast_forward(const struct gossmap *map,
 void gossmap_iter_end(const struct gossmap *map, struct gossmap_iter *iter);
 
 /* For debugging: returns length read, and total known length of file */
-size_t gossmap_lengths(const struct gossmap *map, size_t *total);
+u64 gossmap_lengths(const struct gossmap *map, u64 *total);
 
 /* Debugging: connectd wants to enumerate fds */
 int gossmap_fd(const struct gossmap *map);