wallet: Display addresses derived from scriptPubKey where available

In particular this matches the case of `their_unilateral/to_us` outputs, which
were missing their addresses so far.

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

CHANGELOG.md

@@ -29,6 +29,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - JSON API: `getroute` `riskfactor` argument is simplified; `pay` now defaults to setting it to 10.
 - pylightning: New class 'Millisatoshi' can be used for JSON API, and new '_msat' fields are turned into this on reading.
 - JSON API: `fundchannel` and `withdraw` now have a new parameter `minconf` that limits coinselection to outputs that have at least `minconf` confirmations (default 1). (#2380)
+- JSON API: `listfunds` now displays addresses for all outputs owned by the wallet (#2387)
 
 ### Changed
 

tests/test_closing.py

@@ -1469,6 +1469,12 @@ def test_permfail(node_factory, bitcoind):
     # generated some more blocks.
     assert (closetxid, "confirmed") in set([(o['txid'], o['status']) for o in l1.rpc.listfunds()['outputs']])
 
+    # Check that the all the addresses match what we generated ourselves:
+    for o in l1.rpc.listfunds()['outputs']:
+        txout = bitcoind.rpc.gettxout(o['txid'], o['output'])
+        addr = txout['scriptPubKey']['addresses'][0]
+        assert(addr == o['address'])
+
     addr = l1.bitcoin.rpc.getnewaddress()
     l1.rpc.withdraw(addr, "all")
 

wallet/walletrpc.c

@@ -246,6 +246,26 @@ encode_pubkey_to_addr(const tal_t *ctx,
 	return out;
 }
 
+/* Returns NULL if the script is not a P2WPKH */
+static char *
+encode_scriptpubkey_to_addr(const tal_t *ctx,
+			    const struct lightningd *ld,
+			    const u8 *scriptPubkey)
+{
+	char *out;
+	const char *hrp;
+	size_t scriptLen = tal_bytelen(scriptPubkey);
+	bool ok;
+	if (scriptLen != 22 || scriptPubkey[0] != 0x00 || scriptPubkey[1] != 0x14)
+		return NULL;
+	hrp = get_chainparams(ld)->bip173_name;
+	out = tal_arr(ctx, char, 73 + strlen(hrp));
+	ok = segwit_addr_encode(out, hrp, 0, scriptPubkey + 2, scriptLen - 2);
+	if (!ok)
+		return tal_free(out);
+	return out;
+}
+
 /* Extract a bool indicating "p2sh-segwit" or "bech32" */
 static struct command_result *param_newaddr(struct command *cmd,
 					    const char *name,
@@ -445,7 +465,13 @@ static struct command_result *json_listfunds(struct command *cmd,
 						    "p2wpkh address encoding failure.");
 			}
 		        json_add_string(response, "address", out);
+		} else if (utxos[i]->scriptPubkey != NULL) {
+			out = encode_scriptpubkey_to_addr(
+			    cmd, cmd->ld, utxos[i]->scriptPubkey);
+			if (out)
+				json_add_string(response, "address", out);
 		}
+
 		if (utxos[i]->spendheight)
 			json_add_string(response, "status", "spent");
 		else if (utxos[i]->blockheight)