simplification

lib/lnbase.py

@@ -443,7 +443,8 @@ def make_commitment(ctn, local_funding_pubkey, remote_funding_pubkey, remotepubk
                     payment_basepoint, remote_payment_basepoint,
                     revocation_pubkey, delayed_pubkey, to_self_delay,
                     funding_txid, funding_pos, funding_satoshis,
-                    local_amount, remote_amount, dust_limit_satoshis, local_feerate, commitment_owner, htlcs):
+                    local_amount, remote_amount,
+                    dust_limit_satoshis, local_feerate, for_us, htlcs):
 
     pubkeys = sorted([bh2u(local_funding_pubkey), bh2u(remote_funding_pubkey)])
     obs = get_obscured_ctn(ctn, payment_basepoint, remote_payment_basepoint)
@@ -469,15 +470,8 @@ def make_commitment(ctn, local_funding_pubkey, remote_funding_pubkey, remotepubk
     remote_address = bitcoin.pubkey_to_address('p2wpkh', bh2u(remotepubkey))
     # TODO trim htlc outputs here while also considering 2nd stage htlc transactions
     fee = local_feerate * overall_weight(len(htlcs)) // 1000 # TODO incorrect if anything is trimmed
-    fee_local, fee_remote = 0, 0
-    if commitment_owner == FOR_US:
-      fee_local = fee
-    elif commitment_owner == FOR_REMOTE:
-      fee_remote = fee
-    else:
-      raise Exception("unexpected commitment owner")
-    to_local = (bitcoin.TYPE_ADDRESS, local_address, local_amount - fee_local)
-    to_remote = (bitcoin.TYPE_ADDRESS, remote_address, remote_amount - fee_remote)
+    to_local = (bitcoin.TYPE_ADDRESS, local_address, local_amount - (fee if for_us else 0))
+    to_remote = (bitcoin.TYPE_ADDRESS, remote_address, remote_amount - (fee if not for_us else 0))
     c_outputs = [to_local, to_remote]
     for script, msat_amount in htlcs:
         c_outputs += [(bitcoin.TYPE_ADDRESS, bitcoin.redeem_script_to_address('p2wsh', bh2u(script)), msat_amount // 1000)]
@@ -806,7 +800,7 @@ class Peer(PrintError):
             base_point, remote_payment_basepoint,
             revocation_pubkey, remote_delayedpubkey, remote_delay,
             funding_txid, funding_index, funding_satoshis,
-            remote_amount, local_amount, remote_dust_limit_satoshis, local_feerate, FOR_REMOTE, htlcs=[])
+            remote_amount, local_amount, remote_dust_limit_satoshis, local_feerate, False, htlcs=[])
         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])
@@ -829,7 +823,7 @@ class Peer(PrintError):
             base_point, remote_payment_basepoint,
             remote_revocation_pubkey, local_delayedpubkey, to_self_delay,
             funding_txid, funding_index, funding_satoshis,
-            local_amount, remote_amount, dust_limit_satoshis, local_feerate, FOR_US)
+            local_amount, remote_amount, dust_limit_satoshis, local_feerate, True)
         local_ctx = make_commitment(*local_ctx_args, htlcs=[])
         pre_hash = bitcoin.Hash(bfh(local_ctx.serialize_preimage(0)))
         if not bitcoin.verify_signature(remote_funding_pubkey, remote_sig, pre_hash):

lib/tests/test_lnbase.py

@@ -3,7 +3,6 @@ import json
 import unittest
 
 from lib.util import bh2u, bfh
-from lib.lnbase import FOR_US, FOR_REMOTE
 from lib.lnbase import make_commitment, get_obscured_ctn, Peer, make_offered_htlc, make_received_htlc, make_htlc_tx
 from lib.lnbase import secret_to_pubkey, derive_pubkey, derive_privkey, derive_blinded_pubkey, overall_weight
 from lib.lnbase import make_htlc_tx_output, make_htlc_tx_inputs, get_per_commitment_secret_from_seed
@@ -70,7 +69,8 @@ class Test_LNBase(unittest.TestCase):
             local_payment_basepoint, remote_payment_basepoint,
             local_revocation_pubkey, local_delayedpubkey, local_delay,
             funding_tx_id, funding_output_index, funding_amount_satoshi,
-            local_amount, remote_amount, local_dust_limit_satoshi, local_feerate=local_feerate_per_kw, commitment_owner=FOR_US, htlcs=[])
+            local_amount, remote_amount, local_dust_limit_satoshi,
+            local_feerate_per_kw, True, htlcs=[])
         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)
@@ -159,7 +159,7 @@ class Test_LNBase(unittest.TestCase):
             local_revocation_pubkey, local_delayedpubkey, local_delay,
             funding_tx_id, funding_output_index, funding_amount_satoshi,
             local_amount, remote_amount, local_dust_limit_satoshi,
-            local_feerate=local_feerate_per_kw, commitment_owner=FOR_US, htlcs=htlcs)
+            local_feerate_per_kw, True, 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)