URI: 
       tlnbase: verify remote signature - electrum - Electrum Bitcoin wallet
  HTML git clone https://git.parazyd.org/electrum
   DIR Log
   DIR Files
   DIR Refs
   DIR Submodules
       ---
   DIR commit 21be384603fa044fbf99768a60152686f23a2995
   DIR parent e9bad2e862db17087d2b11a2e5abef79476119c5
  HTML Author: ThomasV <thomasv@electrum.org>
       Date:   Sat, 21 Apr 2018 14:33:41 +0200
       
       lnbase: verify remote signature
       
       Diffstat:
         M lib/lnbase.py                       |      43 +++++++++++++++----------------
         M lib/tests/test_lnbase.py            |      10 +++++-----
       
       2 files changed, 26 insertions(+), 27 deletions(-)
       ---
   DIR diff --git a/lib/lnbase.py b/lib/lnbase.py
       t@@ -428,9 +428,10 @@ def make_received_htlc(revocation_pubkey, remote_htlcpubkey, local_htlcpubkey, p
        
        
        def make_commitment(ctn, local_funding_pubkey, remote_funding_pubkey, remotepubkey,
       -                    payment_basepoint, remote_payment_basepoint, revocation_pubkey, delayed_pubkey,
       +                    payment_basepoint, remote_payment_basepoint,
       +                    revocation_pubkey, delayed_pubkey, to_self_delay,
                            funding_txid, funding_pos, funding_satoshis,
       -                    local_amount, remote_amount, to_self_delay, dust_limit_satoshis, htlcs=[]):
       +                    local_amount, remote_amount, dust_limit_satoshis, htlcs=[]):
            pubkeys = sorted([bh2u(local_funding_pubkey), bh2u(remote_funding_pubkey)])
            obs = get_obscured_ctn(ctn, payment_basepoint, remote_payment_basepoint)
            locktime = (0x20 << 24) + (obs & 0xffffff)
       t@@ -467,7 +468,7 @@ def make_commitment(ctn, local_funding_pubkey, remote_funding_pubkey, remotepubk
        
        class Peer(PrintError):
        
       -    def __init__(self, host, port, pubkey, request_initial_sync=True, network=None):
       +    def __init__(self, host, port, pubkey, request_initial_sync=False, network=None):
                self.host = host
                self.port = port
                self.privkey = os.urandom(32) + b"\x01"
       t@@ -746,8 +747,8 @@ class Peer(PrintError):
                remotepubkey = derive_pubkey(remote_payment_basepoint, per_commitment_point_first)
                revocation_pubkey = derive_blinded_pubkey(revocation_basepoint, remote_per_commitment_point)
                remote_revocation_pubkey = derive_blinded_pubkey(remote_revocation_basepoint, per_commitment_point_first)
       -        local_delayedpubkey = derive_pubkey(delayed_payment_basepoint, remote_per_commitment_point)
       -        remote_delayedpubkey = derive_pubkey(remote_delayed_payment_basepoint, per_commitment_point_first)
       +        local_delayedpubkey = derive_pubkey(delayed_payment_basepoint, per_commitment_point_first)
       +        remote_delayedpubkey = derive_pubkey(remote_delayed_payment_basepoint, remote_per_commitment_point)
                # compute amounts
                htlcs = []
                fee = local_feerate * overall_weight(len(htlcs)) // 1000
       t@@ -758,20 +759,19 @@ class Peer(PrintError):
                # remote commitment transaction
                remote_ctx = make_commitment(
                    ctn,
       -            remote_funding_pubkey, funding_pubkey,    # will be sorted
       -            localpubkey,                              # used in to_remote
       -            base_point, remote_payment_basepoint,     # used by obscured ctn
       -            revocation_pubkey, remote_delayedpubkey,  # used by to_local script
       +            remote_funding_pubkey, funding_pubkey, localpubkey,
       +            base_point, remote_payment_basepoint,
       +            revocation_pubkey, remote_delayedpubkey, remote_delay,
                    funding_txid, funding_index, funding_satoshis,
       -            remote_amount, local_amount, remote_delay, remote_dust_limit_satoshis)
       +            remote_amount, local_amount, remote_dust_limit_satoshis)
                remote_ctx.sign({bh2u(funding_pubkey): (funding_privkey, True)})
                sig_index = pubkeys.index(bh2u(funding_pubkey))
                sig = bytes.fromhex(remote_ctx.inputs()[0]["signatures"][sig_index])
                r, s = sigdecode_der(sig[:-1], SECP256k1.generator.order())
                sig_64 = sigencode_string_canonize(r, s, SECP256k1.generator.order())
       -        funding_txid = bytes.fromhex(funding_txid)[::-1]
       -        channel_id = int.from_bytes(funding_txid, byteorder="big") ^ funding_index
       -        self.send_message(gen_msg("funding_created", temporary_channel_id=temp_channel_id, funding_txid=funding_txid, funding_output_index=funding_index, signature=sig_64))
       +        funding_txid_bytes = bytes.fromhex(funding_txid)[::-1]
       +        channel_id = int.from_bytes(funding_txid_bytes, byteorder="big") ^ funding_index
       +        self.send_message(gen_msg("funding_created", temporary_channel_id=temp_channel_id, funding_txid=funding_txid_bytes, funding_output_index=funding_index, signature=sig_64))
                self.funding_signed[channel_id] = asyncio.Future()
                try:
                    payload = await self.funding_signed[channel_id]
       t@@ -779,27 +779,26 @@ class Peer(PrintError):
                    del self.funding_signed[channel_id]
                self.print_error('received funding_signed')
                remote_sig = payload['signature']
       -        # todo: check signature against local ctx
       +        # verify remote signature
                local_ctx = make_commitment(
                    ctn,
       -            funding_pubkey, remote_funding_pubkey,
       -            remotepubkey,
       +            funding_pubkey, remote_funding_pubkey, remotepubkey,
                    base_point, remote_payment_basepoint,
       -            revocation_pubkey, local_delayedpubkey,
       +            remote_revocation_pubkey, local_delayedpubkey, to_self_delay,
                    funding_txid, funding_index, funding_satoshis,
       -            local_amount, remote_amount, to_self_delay, dust_limit_satoshis)
       -        self.print_error('Done making commitment')
       -
       +            local_amount, remote_amount, dust_limit_satoshis)
       +        pre_hash = bitcoin.Hash(bfh(local_ctx.serialize_preimage(0)))
       +        if not bitcoin.verify_signature(remote_funding_pubkey, remote_sig, pre_hash):
       +            raise Exception('verifying remote signature failed.')
                # broadcast funding tx
                self.local_funding_locked[channel_id] = asyncio.Future()
                self.remote_funding_locked[channel_id] = asyncio.Future()
                success, _txid = self.network.broadcast(funding_tx)
                assert success
                # wait until we see confirmations
       -
                def on_network_update(event, *args):
                    if event == 'updated':
       -                conf = wallet.get_tx_height(bh2u(funding_txid[::-1]))[1]
       +                conf = wallet.get_tx_height(funding_txid)[1]
                        if conf >= funding_txn_minimum_depth:
                            async def set_local_funding_locked_result():
                                try:
   DIR diff --git a/lib/tests/test_lnbase.py b/lib/tests/test_lnbase.py
       t@@ -68,9 +68,9 @@ class Test_LNBase(unittest.TestCase):
                    commitment_number,
                    local_funding_pubkey, remote_funding_pubkey, remotepubkey,
                    local_payment_basepoint, remote_payment_basepoint,
       -            local_revocation_pubkey, local_delayedpubkey,
       +            local_revocation_pubkey, local_delayedpubkey, local_delay,
                    funding_tx_id, funding_output_index, funding_amount_satoshi,
       -            local_amount, remote_amount, local_delay, local_dust_limit_satoshi)
       +            local_amount, remote_amount, local_dust_limit_satoshi)
                self.sign_and_insert_remote_sig(our_commit_tx, remote_funding_pubkey, remote_signature, local_funding_pubkey, local_funding_privkey)
                ref_commit_tx_str = '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'
                self.assertEqual(str(our_commit_tx), ref_commit_tx_str)
       t@@ -158,10 +158,10 @@ class Test_LNBase(unittest.TestCase):
                    commitment_number,
                    local_funding_pubkey, remote_funding_pubkey, remotepubkey,
                    local_payment_basepoint, remote_payment_basepoint,
       -            local_revocation_pubkey, local_delayedpubkey,
       +            local_revocation_pubkey, local_delayedpubkey, loccal_delay,
                    funding_tx_id, funding_output_index, funding_amount_satoshi,
       -            local_amount, remote_amount,
       -            local_delay, local_dust_limit_satoshi, htlcs=htlcs)
       +            local_amount, remote_amount, local_dust_limit_satoshi,
       +            htlcs=htlcs)
                self.sign_and_insert_remote_sig(our_commit_tx, remote_funding_pubkey, remote_signature, local_funding_pubkey, local_funding_privkey)
                self.assertEqual(str(our_commit_tx), output_commit_tx)