wallet: Add primitives to store htlcs in the database

Signed-off-by: Christian Decker <decker.christian@gmail.com>

lightningd/htlc_end.h

@@ -15,6 +15,10 @@ struct htlc_key {
 
 /* Incoming HTLC */
 struct htlc_in {
+	/* The database primary key for this htlc. Must be 0 until it
+	 * is saved to the database, must be >0 after saving to the
+	 * database. */
+	u64 dbid;
 	struct htlc_key key;
 	u64 msatoshi;
 	u32 cltv_expiry;
@@ -39,6 +43,10 @@ struct htlc_in {
 };
 
 struct htlc_out {
+	/* The database primary key for this htlc. Must be 0 until it
+	 * is saved to the database, must be >0 after saving to the
+	 * database. */
+	u64 dbid;
 	struct htlc_key key;
 	u64 msatoshi;
 	u32 cltv_expiry;

wallet/db.c

@@ -99,7 +99,7 @@ char *dbmigrations[] = {
     "  direction INTEGER,"
     "  origin_htlc INTEGER,"
     "  msatoshi INTEGER,"
-    "  ctlv_expiry INTEGER,"
+    "  cltv_expiry INTEGER,"
     "  payment_hash BLOB,"
     "  payment_key BLOB,"
     "  routing_onion BLOB,"
@@ -107,7 +107,6 @@ char *dbmigrations[] = {
     "  malformed_onion INTEGER,"
     "  hstate INTEGER,"
     "  shared_secret BLOB,"
-    "  preimage BLOB,"
     "  PRIMARY KEY (id),"
     "  UNIQUE (channel_id, channel_htlc_id, direction)"
     ");",

wallet/wallet.c

@@ -10,6 +10,8 @@
 #include <lightningd/peer_htlcs.h>
 
 #define SQLITE_MAX_UINT 0x7FFFFFFFFFFFFFFF
+#define DIRECTION_INCOMING 0
+#define DIRECTION_OUTGOING 1
 
 struct wallet *wallet_new(const tal_t *ctx, struct log *log)
 {
@@ -845,6 +847,220 @@ int wallet_extract_owned_outputs(struct wallet *w, const struct bitcoin_tx *tx,
 	return num_utxos;
 }
 
+bool wallet_htlc_save_in(struct wallet *wallet,
+			 const struct wallet_channel *chan, struct htlc_in *in)
+{
+	bool ok = true;
+	tal_t *tmpctx = tal_tmpctx(wallet);
+
+	ok &= db_exec(
+	    __func__, wallet->db,
+	    "INSERT INTO channel_htlcs "
+	    "(channel_id, channel_htlc_id, direction, origin_htlc, msatoshi, cltv_expiry, payment_hash, payment_key, hstate, shared_secret, routing_onion) VALUES "
+	    "(%" PRIu64 ", %"PRIu64", %d, NULL, %"PRIu64", %d, '%s', %s, %d, '%s', '%s');",
+	    chan->id, in->key.id, DIRECTION_INCOMING, in->msatoshi, in->cltv_expiry,
+	    tal_hexstr(tmpctx, &in->payment_hash, sizeof(struct sha256)),
+	    in->preimage == NULL ? "NULL" : tal_hexstr(tmpctx, &in->preimage,
+						       sizeof(struct preimage)),
+	    in->hstate,
+	    tal_hexstr(tmpctx, &in->shared_secret, sizeof(struct secret)),
+	    tal_hexstr(tmpctx, &in->onion_routing_packet, sizeof(in->onion_routing_packet))
+	);
+
+	tal_free(tmpctx);
+	if (ok) {
+		in->dbid = sqlite3_last_insert_rowid(wallet->db->sql);
+	}
+	return ok;
+}
+
+bool wallet_htlc_save_out(struct wallet *wallet,
+			  const struct wallet_channel *chan,
+			  struct htlc_out *out)
+{
+	bool ok = true;
+	tal_t *tmpctx = tal_tmpctx(wallet);
+
+	/* We absolutely need the incoming HTLC to be persisted before
+	 * we can persist it's dependent */
+	assert(out->in == NULL || out->in->dbid != 0);
+
+	ok &= db_exec(
+	    __func__, wallet->db,
+	    "INSERT INTO channel_htlcs "
+	    "(channel_id, channel_htlc_id, direction, origin_htlc, msatoshi, cltv_expiry, "
+	    "payment_hash, payment_key, hstate, shared_secret, routing_onion) VALUES "
+	    "(%" PRIu64 ", %" PRIu64 ", %d, %s, %" PRIu64", %d, '%s', %s, %d, NULL, '%s');",
+	    chan->id,
+	    out->key.id,
+	    DIRECTION_OUTGOING,
+	    out->in ? tal_fmt(tmpctx, "%" PRIu64, out->in->dbid) : "NULL",
+	    out->msatoshi,
+	    out->cltv_expiry,
+	    tal_hexstr(tmpctx, &out->payment_hash, sizeof(struct sha256)),
+	    out->preimage ? tal_hexstr(tmpctx, &out->preimage, sizeof(struct preimage)) : "NULL",
+	    out->hstate,
+	    tal_hexstr(tmpctx, &out->onion_routing_packet, sizeof(out->onion_routing_packet))
+	);
+
+	tal_free(tmpctx);
+	if (ok) {
+		out->dbid = sqlite3_last_insert_rowid(wallet->db->sql);
+	}
+	return ok;
+}
+
+bool wallet_htlc_update(struct wallet *wallet, const u64 htlc_dbid,
+			const enum htlc_state new_state,
+			const struct preimage *payment_key)
+{
+	bool ok = true;
+	tal_t *tmpctx = tal_tmpctx(wallet);
+
+	if (payment_key) {
+		ok &= db_exec(
+		    __func__, wallet->db, "UPDATE channel_htlcs SET hstate=%d, "
+					  "payment_key='%s' WHERE id=%" PRIu64,
+		    new_state,
+		    tal_hexstr(tmpctx, payment_key, sizeof(struct preimage)),
+		    htlc_dbid);
+
+	} else {
+		ok &= db_exec(
+		    __func__, wallet->db,
+		    "UPDATE channel_htlcs SET hstate = %d WHERE id=%" PRIu64,
+		    new_state, htlc_dbid);
+	}
+	tal_free(tmpctx);
+	return ok;
+}
+
+static bool wallet_stmt2htlc_in(const struct wallet_channel *channel,
+				sqlite3_stmt *stmt, struct htlc_in *in)
+{
+	bool ok = true;
+	in->dbid = sqlite3_column_int64(stmt, 0);
+	in->key.id = sqlite3_column_int64(stmt, 1);
+	in->key.peer = channel->peer;
+	in->msatoshi = sqlite3_column_int64(stmt, 2);
+	in->cltv_expiry = sqlite3_column_int(stmt, 3);
+	in->hstate = sqlite3_column_int(stmt, 4);
+
+	ok &= sqlite3_column_hexval(stmt, 5, &in->payment_hash,
+			      sizeof(in->payment_hash));
+	ok &= sqlite3_column_hexval(stmt, 6, &in->shared_secret,
+			      sizeof(in->shared_secret));
+
+	if (sqlite3_column_type(stmt, 7) != SQLITE_NULL) {
+		in->preimage = tal(in, struct preimage);
+		ok &= sqlite3_column_hexval(stmt, 7, in->preimage, sizeof(*in->preimage));
+	} else {
+		in->preimage = NULL;
+	}
+
+	sqlite3_column_hexval(stmt, 8, &in->onion_routing_packet,
+			      sizeof(in->onion_routing_packet));
+
+	in->failuremsg = NULL;
+	in->malformed = 0;
+
+	return ok;
+}
+static bool wallet_stmt2htlc_out(const struct wallet_channel *channel,
+				sqlite3_stmt *stmt, struct htlc_out *out)
+{
+	bool ok = true;
+	out->dbid = sqlite3_column_int64(stmt, 0);
+	out->key.id = sqlite3_column_int64(stmt, 1);
+	out->key.peer = channel->peer;
+	out->msatoshi = sqlite3_column_int64(stmt, 2);
+	out->cltv_expiry = sqlite3_column_int(stmt, 3);
+	out->hstate = sqlite3_column_int(stmt, 4);
+	ok &= sqlite3_column_hexval(stmt, 5, &out->payment_hash,
+			      sizeof(out->payment_hash));
+
+	if (sqlite3_column_type(stmt, 6) != SQLITE_NULL) {
+		out->origin_htlc_id = sqlite3_column_int64(stmt, 6);
+	} else {
+		out->origin_htlc_id = 0;
+	}
+
+	if (sqlite3_column_type(stmt, 7) != SQLITE_NULL) {
+		out->preimage = tal(out, struct preimage);
+		ok &= sqlite3_column_hexval(stmt, 7, &out->preimage, sizeof(struct preimage));
+	} else {
+		out->preimage = NULL;
+	}
+
+	sqlite3_column_hexval(stmt, 8, &out->onion_routing_packet,
+			      sizeof(out->onion_routing_packet));
+
+	out->failuremsg = NULL;
+	out->malformed = 0;
+
+	/* Need to defer wiring until we can look up all incoming
+	 * htlcs, will wire using origin_htlc_id */
+	out->in = NULL;
+
+	return ok;
+}
+
+bool wallet_htlcs_load_for_channel(struct wallet *wallet,
+				   struct wallet_channel *chan,
+				   struct htlc_in_map *htlcs_in,
+				   struct htlc_out_map *htlcs_out)
+{
+	bool ok = true;
+	int incount = 0, outcount = 0;
+
+	log_debug(wallet->log, "Loading HTLCs for channel %"PRIu64, chan->id);
+	sqlite3_stmt *stmt = db_query(
+	    __func__, wallet->db,
+	    "SELECT id, channel_htlc_id, msatoshi, cltv_expiry, hstate, "
+	    "payment_hash, shared_secret, payment_key FROM channel_htlcs WHERE "
+	    "direction=%d AND channel_id=%" PRIu64 " AND hstate != %d",
+	    DIRECTION_INCOMING, chan->id, SENT_REMOVE_ACK_REVOCATION);
+
+	if (!stmt) {
+		log_broken(wallet->log, "Could not select htlc_ins: %s", wallet->db->err);
+		return false;
+	}
+
+	while (ok && stmt && sqlite3_step(stmt) == SQLITE_ROW) {
+		struct htlc_in *in = tal(chan, struct htlc_in);
+		ok &= wallet_stmt2htlc_in(chan, stmt, in);
+		connect_htlc_in(htlcs_in, in);
+		ok &=  htlc_in_check(in, "wallet_htlcs_load") != NULL;
+		incount++;
+	}
+	sqlite3_finalize(stmt);
+
+	stmt = db_query(
+	    __func__, wallet->db,
+	    "SELECT id, channel_htlc_id, msatoshi, cltv_expiry, hstate, "
+	    "payment_hash, origin_htlc, payment_key FROM channel_htlcs WHERE "
+	    "direction=%d AND channel_id=%" PRIu64 " AND hstate != %d",
+	    DIRECTION_OUTGOING, chan->id, RCVD_REMOVE_ACK_REVOCATION);
+
+	if (!stmt) {
+		log_broken(wallet->log, "Could not select htlc_outs: %s", wallet->db->err);
+		return false;
+	}
+
+	while (ok && stmt && sqlite3_step(stmt) == SQLITE_ROW) {
+		struct htlc_out *out = tal(chan, struct htlc_out);
+		ok &= wallet_stmt2htlc_out(chan, stmt, out);
+		connect_htlc_out(htlcs_out, out);
+		/* Cannot htlc_out_check because we haven't wired the
+		 * dependencies in yet */
+		outcount++;
+	}
+	sqlite3_finalize(stmt);
+	log_debug(wallet->log, "Restored %d incoming and %d outgoing HTLCS", incount, outcount);
+
+	return ok;
+}
+
 /**
  * wallet_shachain_delete - Drop the shachain from the database
  *

wallet/wallet.h

@@ -9,6 +9,7 @@
 #include <ccan/tal/tal.h>
 #include <common/channel_config.h>
 #include <common/utxo.h>
+#include <lightningd/htlc_end.h>
 #include <wally_bip32.h>
 
 struct lightningd;
@@ -219,4 +220,48 @@ bool wallet_channels_load_active(struct wallet *w, struct list_head *peers);
 int wallet_extract_owned_outputs(struct wallet *w, const struct bitcoin_tx *tx,
 				 u64 *total_satoshi);
 
+/**
+ * wallet_htlc_save_in - store a htlc_in in the database
+ *
+ * @wallet: wallet to store the htlc into
+ * @chan: the `wallet_channel` this HTLC is associated with
+ * @in: the htlc_in to store
+ *
+ * This will store the contents of the `struct htlc_in` in the
+ * database. Since `struct htlc_in` commonly only change state after
+ * being created we do not support updating arbitrary fields and this
+ * function will fail when attempting to call it multiple times for
+ * the same `struct htlc_in`. Instead `wallet_htlc_update` may be used
+ * for state transitions or to set the `payment_key` for completed
+ * HTLCs.
+ */
+bool wallet_htlc_save_in(struct wallet *wallet,
+			 const struct wallet_channel *chan, struct htlc_in *in);
+
+/**
+ * wallet_htlc_save_out - store a htlc_out in the database
+ *
+ * See comment for wallet_htlc_save_in.
+ */
+bool wallet_htlc_save_out(struct wallet *wallet,
+			  const struct wallet_channel *chan,
+			  struct htlc_out *out);
+
+/**
+ * wallet_htlc_update - perform state transition or add payment_key
+ *
+ * @wallet: the wallet containing the HTLC to update
+ * @htlc_dbid: the database ID used to identify the HTLC
+ * @new_state: the state we should transition to
+ * @payment_key: the `payment_key` which hashes to the `payment_hash`,
+ *   or NULL if unknown.
+ *
+ * Used to update the state of an HTLC, either a `struct htlc_in` or a
+ * `struct htlc_out` and optionally set the `payment_key` should the
+ * HTLC have been settled.
+ */
+bool wallet_htlc_update(struct wallet *wallet, const u64 htlc_dbid,
+			const enum htlc_state new_state,
+			const struct preimage *payment_key);
+
 #endif /* WALLET_WALLET_H */

wallet/wallet_tests.c

@@ -294,6 +294,48 @@ static bool test_channel_config_crud(const tal_t *ctx)
        	return true;
 }
 
+static bool test_htlc_crud(const tal_t *ctx)
+{
+	struct htlc_in in;
+	struct htlc_out out;
+	struct preimage payment_key;
+	struct wallet_channel chan;
+	struct wallet *w = create_test_wallet(ctx);
+
+	/* Make sure we have our references correct */
+	db_exec(__func__, w->db, "INSERT INTO channels (id) VALUES (1);");
+	chan.id = 1;
+
+	memset(&in, 0, sizeof(in));
+	memset(&out, 0, sizeof(out));
+	memset(&in.payment_hash, 'A', sizeof(struct sha256));
+	memset(&out.payment_hash, 'A', sizeof(struct sha256));
+	memset(&payment_key, 'B', sizeof(payment_key));
+	out.in = ∈
+	out.key.id = 1337;
+
+	/* Store the htlc_in */
+	CHECK_MSG(wallet_htlc_save_in(w, &chan, &in),
+		  tal_fmt(ctx, "Save htlc_in failed: %s", w->db->err));
+	CHECK_MSG(in.dbid != 0, "HTLC DB ID was not set.");
+	/* Saving again should get us a collision */
+	CHECK_MSG(!wallet_htlc_save_in(w, &chan, &in),
+		  "Saving two HTLCs with the same data must not succeed.");
+	/* Update */
+	CHECK_MSG(wallet_htlc_update(w, in.dbid, RCVD_ADD_HTLC, NULL),
+		  "Update HTLC with null payment_key failed");
+	CHECK_MSG(
+	    wallet_htlc_update(w, in.dbid, SENT_REMOVE_HTLC, &payment_key),
+	    "Update HTLC with payment_key failed");
+
+	CHECK_MSG(wallet_htlc_save_out(w, &chan, &out),
+		  tal_fmt(ctx, "Save htlc_out failed: %s", w->db->err));
+	CHECK_MSG(out.dbid != 0, "HTLC DB ID was not set.");
+	CHECK_MSG(!wallet_htlc_save_out(w, &chan, &out),
+		  "Saving two HTLCs with the same data must not succeed.");
+	return true;
+}
+
 int main(void)
 {
 	bool ok = true;
@@ -303,6 +345,7 @@ int main(void)
 	ok &= test_shachain_crud();
 	ok &= test_channel_crud(tmpctx);
 	ok &= test_channel_config_crud(tmpctx);
+	ok &= test_htlc_crud(tmpctx);
 
 	tal_free(tmpctx);
 	return !ok;