From b469df5283f9ba890555666299338974fbf3a308 Mon Sep 17 00:00:00 2001
From: ThomasV <thomasv@electrum.org>
Date: Thu, 21 Nov 2019 20:16:04 +0100
Subject: [PATCH] check channel funding_tx amount and script in
 save_short_channel_id

---
 electrum/lnpeer.py   | 15 ---------------
 electrum/lnworker.py | 39 +++++++++++++++++++++++++++------------
 2 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/electrum/lnpeer.py b/electrum/lnpeer.py
index ce843768b..d15fe10ae 100644
--- a/electrum/lnpeer.py
+++ b/electrum/lnpeer.py
@@ -680,21 +680,6 @@ class Peer(Logger):
         self.lnworker.save_channel(chan)
         self.lnworker.lnwatcher.add_channel(chan.funding_outpoint.to_str(), chan.get_funding_address())
         self.lnworker.on_channels_updated()
-        # TODO make more robust
-        while True:
-            try:
-                funding_tx = Transaction(await self.network.get_transaction(funding_txid))
-            except NetworkException as e:
-                print("sleeping", str(e))
-                await asyncio.sleep(1)
-            else:
-                break
-        outp = funding_tx.outputs()[funding_idx]
-        redeem_script = funding_output_script(chan.config[REMOTE], chan.config[LOCAL])
-        funding_address = bitcoin.redeem_script_to_address('p2wsh', redeem_script)
-        if not (outp.address == funding_address and outp.value == funding_sat):
-            chan.set_state('DISCONNECTED')
-            raise Exception('funding outpoint mismatch')
 
     def validate_remote_reserve(self, payload_field: bytes, dust_limit: int, funding_sat: int) -> int:
         remote_reserve_sat = int.from_bytes(payload_field, 'big')
diff --git a/electrum/lnworker.py b/electrum/lnworker.py
index 1b268b9ed..58fe461ad 100644
--- a/electrum/lnworker.py
+++ b/electrum/lnworker.py
@@ -41,6 +41,8 @@ from .ecc import der_sig_from_sig_string
 from .ecc_fast import is_using_fast_ecc
 from .lnchannel import Channel, ChannelJsonEncoder
 from . import lnutil
+from .lnutil import funding_output_script
+from .bitcoin import redeem_script_to_address
 from .lnutil import (Outpoint, LNPeerAddr,
                      get_compressed_pubkey_from_bech32, extract_nodeid,
                      PaymentFailure, split_host_port, ConnStringFormatError,
@@ -604,19 +606,32 @@ class LNWallet(LNWorker):
         if it's also deep enough, also save to disk.
         Returns tuple (mined_deep_enough, num_confirmations).
         """
-        conf = self.lnwatcher.get_tx_height(chan.funding_outpoint.txid).conf
-        if conf > 0:
-            block_height, tx_pos = self.lnwatcher.get_txpos(chan.funding_outpoint.txid)
-            assert tx_pos >= 0
-            chan.short_channel_id_predicted = ShortChannelID.from_components(
-                block_height, tx_pos, chan.funding_outpoint.output_index)
-        if conf >= chan.constraints.funding_txn_minimum_depth > 0:
-            chan.short_channel_id = chan.short_channel_id_predicted
-            self.logger.info(f"save_short_channel_id: {chan.short_channel_id}")
-            self.save_channel(chan)
-            self.on_channels_updated()
-        else:
+        funding_txid = chan.funding_outpoint.txid
+        funding_idx = chan.funding_outpoint.output_index
+        conf = self.lnwatcher.get_tx_height(funding_txid).conf
+        if conf < chan.constraints.funding_txn_minimum_depth:
             self.logger.info(f"funding tx is still not at sufficient depth. actual depth: {conf}")
+            return
+        assert conf > 0
+        # check funding_tx amount and script
+        funding_tx = self.lnwatcher.db.get_transaction(funding_txid)
+        if not funding_tx:
+            self.logger.info(f"no funding_tx {funding_txid}")
+            return
+        outp = funding_tx.outputs()[funding_idx]
+        redeem_script = funding_output_script(chan.config[REMOTE], chan.config[LOCAL])
+        funding_address = redeem_script_to_address('p2wsh', redeem_script)
+        funding_sat = chan.constraints.capacity
+        if not (outp.address == funding_address and outp.value == funding_sat):
+            self.logger.info('funding outpoint mismatch')
+            return
+        block_height, tx_pos = self.lnwatcher.get_txpos(chan.funding_outpoint.txid)
+        assert tx_pos >= 0
+        chan.short_channel_id = ShortChannelID.from_components(
+            block_height, tx_pos, chan.funding_outpoint.output_index)
+        self.logger.info(f"save_short_channel_id: {chan.short_channel_id}")
+        self.save_channel(chan)
+        self.on_channels_updated()
 
     def channel_by_txo(self, txo):
         with self.lock: