db: save and restore accepted payments.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

daemon/db.c

@@ -8,6 +8,7 @@
 #include "names.h"
 #include "netaddr.h"
 #include "pay.h"
+#include "payment.h"
 #include "routing.h"
 #include "secrets.h"
 #include "utils.h"
@@ -1071,6 +1072,40 @@ static void db_load_pay(struct lightningd_state *dstate)
 	tal_free(ctx);
 }
 
+static void db_load_payment(struct lightningd_state *dstate)
+{
+	int err;
+	sqlite3_stmt *stmt;
+	char *ctx = tal(dstate, char);
+
+	err = sqlite3_prepare_v2(dstate->db->sql, "SELECT * FROM payment;", -1,
+				 &stmt, NULL);
+
+	if (err != SQLITE_OK)
+		fatal("db_load_payment:prepare gave %s:%s",
+		      sqlite3_errstr(err), sqlite3_errmsg(dstate->db->sql));
+
+	while ((err = sqlite3_step(stmt)) != SQLITE_DONE) {
+		struct rval r;
+		u64 msatoshis;
+		bool complete;
+
+		if (err != SQLITE_ROW)
+			fatal("db_load_payment:step gave %s:%s",
+			      sqlite3_errstr(err),
+			      sqlite3_errmsg(dstate->db->sql));
+		if (sqlite3_column_count(stmt) != 3)
+			fatal("db_load_pay:step gave %i cols, not 3",
+			      sqlite3_column_count(stmt));
+
+		from_sql_blob(stmt, 0, &r, sizeof(r));
+		msatoshis = sqlite3_column_int64(stmt, 1);
+		complete = sqlite3_column_int(stmt, 2);
+		payment_add(dstate, &r, msatoshis, complete);
+	}
+	tal_free(ctx);
+}
+
 static void db_load_addresses(struct lightningd_state *dstate)
 {
 	int err;
@@ -1112,6 +1147,7 @@ static void db_load(struct lightningd_state *dstate)
 	db_load_addresses(dstate);
 	db_load_peers(dstate);
 	db_load_pay(dstate);
+	db_load_payment(dstate);
 }
 
 void db_init(struct lightningd_state *dstate)
@@ -1158,6 +1194,9 @@ void db_init(struct lightningd_state *dstate)
 			       SQL_BLOB(ids), SQL_PUBKEY(htlc_peer),
 			       SQL_U64(htlc_id), SQL_R(r), SQL_FAIL(fail),
 			       "PRIMARY KEY(rhash)")
+			 TABLE(payment,
+			       SQL_R(r), SQL_U64(msatoshis), SQL_BOOL(complete),
+			       "PRIMARY KEY(r)")
 			 TABLE(anchors,
 			       SQL_PUBKEY(peer),
 			       SQL_TXID(txid), SQL_U32(idx), SQL_U64(amount),
@@ -1886,3 +1925,40 @@ bool db_complete_pay_command(struct lightningd_state *dstate,
 	tal_free(ctx);
 	return !errmsg;
 }
+
+bool db_new_payment(struct lightningd_state *dstate,
+		    u64 msatoshis,
+		    const struct rval *r)
+{
+	const char *errmsg, *ctx = tal(dstate, char);
+
+	log_debug(dstate->base_log, "%s", __func__);
+
+	assert(!dstate->db->in_transaction);
+	
+	errmsg = db_exec(ctx, dstate, "INSERT INTO payment VALUES (x'%s', %"PRIu64", %s);",
+			 tal_hexstr(ctx, r, sizeof(*r)),
+			 msatoshis,
+			 sql_bool(false));
+	if (errmsg)
+		log_broken(dstate->base_log, "%s:%s", __func__, errmsg);
+	tal_free(ctx);
+	return !errmsg;
+}
+
+bool db_resolve_payment(struct lightningd_state *dstate, const struct rval *r)
+{
+	const char *errmsg, *ctx = tal(dstate, char);
+
+	log_debug(dstate->base_log, "%s", __func__);
+
+	assert(dstate->db->in_transaction);
+	
+	errmsg = db_exec(ctx, dstate, "UPDATE payment SET complete=%s WHERE r=x'%s';",
+			 sql_bool(true),
+			 tal_hexstr(ctx, r, sizeof(*r)));
+	if (errmsg)
+		log_broken(dstate->base_log, "%s:%s", __func__, errmsg);
+	tal_free(ctx);
+	return !errmsg;
+}

daemon/db.h

@@ -37,6 +37,9 @@ bool db_replace_pay_command(struct lightningd_state *dstate,
 			    const struct pubkey *ids,
 			    u64 msatoshis,
 			    const struct htlc *htlc);
+bool db_new_payment(struct lightningd_state *dstate,
+		    u64 msatoshis,
+		    const struct rval *r);
 
 /* FIXME: save error handling until db_commit_transaction for calls
  * which have to be inside transaction anyway. */
@@ -46,8 +49,9 @@ bool db_new_htlc(struct peer *peer, const struct htlc *htlc);
 bool db_new_feechange(struct peer *peer, const struct feechange *feechange);
 bool db_update_htlc_state(struct peer *peer, const struct htlc *htlc,
 				 enum htlc_state oldstate);
-bool db_complete_pay_command(struct lightningd_state *state,
+bool db_complete_pay_command(struct lightningd_state *dstate,
 			     const struct htlc *htlc);
+bool db_resolve_payment(struct lightningd_state *dstate, const struct rval *r);
 bool db_update_feechange_state(struct peer *peer,
 			       const struct feechange *f,
 			       enum htlc_state oldstate);

daemon/payment.c

@@ -1,3 +1,4 @@
+#include "db.h"
 #include "jsonrpc.h"
 #include "lightningd.h"
 #include "payment.h"
@@ -17,6 +18,20 @@ struct payment *find_payment(struct lightningd_state *dstate,
 	return NULL;
 }
 
+void payment_add(struct lightningd_state *dstate,
+		 const struct rval *r,
+		 u64 msatoshis,
+		 bool complete)
+{
+	struct payment *payment = tal(dstate, struct payment);
+
+	payment->msatoshis = msatoshis;
+	payment->r = *r;
+	payment->complete = complete;
+	sha256(&payment->rhash, payment->r.r, sizeof(payment->r.r));
+	list_add(&dstate->payments, &payment->list);
+}
+
 static void json_accept_payment(struct command *cmd,
 				const char *buffer, const jsmntok_t *params)
 {
@@ -57,7 +72,12 @@ static void json_accept_payment(struct command *cmd,
 			     buffer + msatoshis->start);
 		return;
 	}
+	payment->complete = false;
 
+	if (!db_new_payment(cmd->dstate, payment->msatoshis, &payment->r)) {
+		command_fail(cmd, "database error");
+		return;
+	}		
 	/* OK, connect it to main state, respond with hash */
 	tal_steal(cmd->dstate, payment);
 	list_add(&cmd->dstate->payments, &payment->list);

daemon/payment.h

@@ -10,8 +10,15 @@ struct payment {
 	u64 msatoshis;
 	struct rval r;
 	struct sha256 rhash;
+	bool complete;
 };
 
+/* From database */
+void payment_add(struct lightningd_state *dstate,
+		 const struct rval *r,
+		 u64 msatoshis,
+		 bool complete);
+
 struct payment *find_payment(struct lightningd_state *dstate,
 			     const struct sha256 *rhash);
 

daemon/peer.c

@@ -560,9 +560,28 @@ static void their_htlc_added(struct peer *peer, struct htlc *htlc,
 			return;
 		}
 
+		/* This is a courtesy: we could simply take your money! */
+		if (payment->complete) {
+			log_unusual(peer->log,
+				    "Repeated payment for HTLC %"PRIu64,
+				    htlc->id);
+			command_htlc_set_fail(peer, htlc,
+					      UNAUTHORIZED_401,
+					      "already received payment");
+			return;
+		}
+
 		log_info(peer->log, "Immediately resolving HTLC %"PRIu64,
 			 htlc->id);
 
+		if (!db_resolve_payment(peer->dstate, &payment->r)) {
+			command_htlc_set_fail(peer, htlc,
+					      INTERNAL_SERVER_ERROR_500,
+					      "database error");
+			return;
+		}
+
+		payment->complete = true;
 		set_htlc_rval(peer, htlc, &payment->r);
 		command_htlc_fulfill(peer, htlc);
 		goto free_rest;

daemon/test/test.sh

@@ -386,9 +386,10 @@ EOF
 cp $DIR2/config $DIR3/config
 
 if [ x"$RECONNECT" = xrestart ]; then
-    # Make sure node2 restarts on same port, by setting in config.
+    # Make sure node2 & 3 restart on same port, by setting in config.
     # Find a free TCP port.
     echo port=`findport 4000` >> $DIR2/config
+    echo port=`findport 4010` >> $DIR3/config
 fi
 
 if [ -n "$DIFFERENT_FEES" ]; then
@@ -418,7 +419,8 @@ else
     LIGHTNINGD2="$PREFIX $LIGHTNINGD2"
     $LIGHTNINGD2 > $REDIR2 2> $REDIRERR2 &
 fi
-$PREFIX ../lightningd --lightning-dir=$DIR3 > $DIR3/output 2> $DIR3/errors &
+LIGHTNINGD3="$PREFIX $(readlink -f `pwd`/../lightningd) --lightning-dir=$DIR3"
+$LIGHTNINGD3 > $DIR3/output 2> $DIR3/errors &
 
 if ! check "$LCLI1 getlog 2>/dev/null | $FGREP Hello"; then
     echo Failed to start daemon 1 >&2
@@ -1028,6 +1030,15 @@ if [ ! -n "$MANUALCOMMIT" ]; then
 	exit 1
     fi
 
+    # If restarting, make sure node3 remembers incoming payment.
+    if [ "$RECONNECT" = restart ]; then
+	$LCLI3 -- dev-restart $LIGHTNINGD3 >/dev/null 2>&1 || true
+	if ! check "$LCLI3 getpeers | tr -s '\012\011\" ' ' ' | fgrep -q 'connected : true'"; then
+	    echo "Failed to reconnect!">&2
+	    exit 1
+	fi
+    fi
+    
     # Pay correctly.
     lcli1 sendpay "$ROUTE" $RHASH5
 
@@ -1035,6 +1046,25 @@ if [ ! -n "$MANUALCOMMIT" ]; then
     # Note that it is delayed a little, since node2 fulfils as soon as fulfill
     # starts.
     check lcli3 "getpeers | $FGREP \"\\\"our_amount\\\" : $(($HTLC_AMOUNT - $NO_HTLCS_FEE / 2))\""
+
+    # If restarting, make sure node3 remembers completed payment.
+    if [ "$RECONNECT" = restart ]; then
+	echo RESTARTING NODE3
+	$LCLI3 -- dev-restart $LIGHTNINGD3 >/dev/null 2>&1 || true
+	if ! check "$LCLI3 getpeers 2>/dev/null | tr -s '\012\011\" ' ' ' | fgrep -q 'connected : true'"; then
+	    echo "Failed to reconnect!">&2
+	    exit 1
+	fi
+    fi
+
+    # Can't pay twice (try from node2)
+    ROUTE2=`lcli2 getroute $ID3 $HTLC_AMOUNT`
+    ROUTE2=`echo $ROUTE2 | sed 's/^{ "route" : \(.*\) }$/\1/'`
+    if lcli2 sendpay "$ROUTE2" $RHASH5; then
+	echo "Paying twice worked?" >&2
+	exit 1
+    fi
+
     lcli3 close $ID2
 
     # Re-send should be a noop (doesn't matter that node3 is down!)