lnonion: use IntEnum and IntFlag for failure codes

electrum/lnbase.py

@@ -25,7 +25,7 @@ from .crypto import sha256
 from . import constants
 from .util import PrintError, bh2u, print_error, bfh, log_exceptions
 from .transaction import Transaction, TxOutput
-from .lnonion import new_onion_packet, OnionHopsDataSingle, OnionPerHop, decode_onion_error, ONION_FAILURE_CODE_MAP
+from .lnonion import new_onion_packet, OnionHopsDataSingle, OnionPerHop, decode_onion_error, OnionFailureCode
 from .lnaddr import lndecode
 from .lnhtlc import HTLCStateMachine, RevokeAndAck
 from .lnutil import (Outpoint, ChannelConfig, LocalState,
@@ -467,9 +467,12 @@ class Peer(PrintError):
             # Note that this is prone to a race.. we might not have a short_channel_id
             # associated with the channel in some cases
             short_channel_id = payload['short_channel_id']
+            self.print_error("not found channel announce for channel update in db", bh2u(short_channel_id))
             for chan in self.channels.values():
                 if chan.short_channel_id_predicted == short_channel_id:
                     chan.pending_channel_update_message = payload
+                    self.print_error("channel update is for our own private channel", bh2u(short_channel_id))
+                    break
 
     def on_channel_announcement(self, payload):
         self.channel_db.on_channel_announcement(payload)
@@ -1022,10 +1025,9 @@ class Peer(PrintError):
             self.print_error("UPDATE_FAIL_HTLC. cannot decode! attempted route is MISSING. {}".format(key))
         else:
             failure_msg, sender_idx = decode_onion_error(payload["reason"], [x.node_id for x in route], chan.onion_keys[htlc_id])
-            code = failure_msg.code
-            code_name = ONION_FAILURE_CODE_MAP.get(code, 'unknown_error??')
+            code = OnionFailureCode(failure_msg.code)
             data = failure_msg.data
-            self.print_error("UPDATE_FAIL_HTLC", code_name, code, data)
+            self.print_error("UPDATE_FAIL_HTLC", repr(code), data)
             try:
                 short_chan_id = route[sender_idx + 1].short_channel_id
             except IndexError:
@@ -1034,7 +1036,6 @@ class Peer(PrintError):
                 # TODO this should depend on the error
                 # also, we need finer blacklisting (directed edges; nodes)
                 self.network.path_finder.blacklist.add(short_chan_id)
-            self.print_error("HTLC failure with code {} ({})".format(code, code_name))
         # process update_fail_htlc on channel
         chan = self.channels[channel_id]
         chan.receive_fail_htlc(htlc_id)

electrum/lnonion.py

@@ -27,6 +27,7 @@ import hashlib
 import hmac
 from collections import namedtuple
 from typing import Sequence
+from enum import IntEnum, IntFlag
 
 from cryptography.hazmat.primitives.ciphers import Cipher, algorithms
 from cryptography.hazmat.backends import default_backend
@@ -299,33 +300,46 @@ def get_failure_msg_from_onion_error(decrypted_error_packet: bytes) -> OnionRout
     return OnionRoutingFailureMessage(failure_code, failure_data)
 
 
-ONION_FC_BADONION = BADONION = 0x8000
-ONION_FC_PERM     = PERM     = 0x4000
-ONION_FC_NODE     = NODE     = 0x2000
-ONION_FC_UPDATE   = UPDATE   = 0x1000
-ONION_FAILURE_CODE_MAP = {
-    PERM | 1 : 'invalid_realm',
-    NODE | 2 : 'temporary_node_failure',
-    PERM | NODE | 2 : 'permanent_node_failure',
-    PERM | NODE | 3 : 'required_node_feature_missing',
-    BADONION | PERM | 4 : 'invalid_onion_version',
-    BADONION | PERM | 5 : 'invalid_onion_hmac',
-    BADONION | PERM | 6 : 'invalid_onion_key',
-    UPDATE | 7 : 'temporary_channel_failure',
-    PERM | 8 : 'permanent_channel_failure',
-    PERM | 9 : 'required_channel_feature_missing',
-    PERM | 10 : 'unknown_next_peer',
-    UPDATE | 11 : 'amount_below_minimum',
-    UPDATE | 12 : 'fee_insufficient',
-    UPDATE | 13 : 'incorrect_cltv_expiry',
-    UPDATE | 14 : 'expiry_too_soon',
-    PERM | 15 : 'unknown_payment_hash',
-    PERM | 16 : 'incorrect_payment_amount',
-    17 : 'final_expiry_too_soon',
-    18 : 'final_incorrect_cltv_expiry',
-    19 : 'final_incorrect_htlc_amount',
-    UPDATE | 20 : 'channel_disabled',
-    21 : 'expiry_too_far',
-}
+class OnionFailureCodeMetaFlag(IntFlag):
+    BADONION = 0x8000
+    PERM     = 0x4000
+    NODE     = 0x2000
+    UPDATE   = 0x1000
+
+BADONION = OnionFailureCodeMetaFlag.BADONION
+PERM     = OnionFailureCodeMetaFlag.PERM
+NODE     = OnionFailureCodeMetaFlag.NODE
+UPDATE   = OnionFailureCodeMetaFlag.UPDATE
+class OnionFailureCode(IntEnum):
+    INVALID_REALM =                           PERM | 1
+    TEMPORARY_NODE_FAILURE =                  NODE | 2
+    PERMANENT_NODE_FAILURE =                  PERM | NODE | 2
+    REQUIRED_NODE_FEATURE_MISSING =           PERM | NODE | 3
+    INVALID_ONION_VERSION =                   BADONION | PERM | 4
+    INVALID_ONION_HMAC =                      BADONION | PERM | 5
+    INVALID_ONION_KEY =                       BADONION | PERM | 6
+    TEMPORARY_CHANNEL_FAILURE =               UPDATE | 7
+    PERMANENT_CHANNEL_FAILURE =               PERM | 8
+    REQUIRED_CHANNEL_FEATURE_MISSING =        PERM | 9
+    UNKNOWN_NEXT_PEER =                       PERM | 10
+    AMOUNT_BELOW_MINIMUM =                    UPDATE | 11
+    FEE_INSUFFICIENT =                        UPDATE | 12
+    INCORRECT_CLTV_EXPIRY =                   UPDATE | 13
+    EXPIRY_TOO_SOON =                         UPDATE | 14
+    UNKNOWN_PAYMENT_HASH =                    PERM | 15
+    INCORRECT_PAYMENT_AMOUNT =                PERM | 16
+    FINAL_EXPIRY_TOO_SOON =                   17
+    FINAL_INCORRECT_CLTV_EXPIRY =             18
+    FINAL_INCORRECT_HTLC_AMOUNT =             19
+    CHANNEL_DISABLED =                        UPDATE | 20
+    EXPIRY_TOO_FAR =                          21
+
+    @classmethod
+    def _missing_(cls, value: int) -> int:
+        # note that for unknown error codes, we return an int,
+        # not an instance of cls
+        return value
+
+
 # don't use these elsewhere, the names are ambiguous without context
 del BADONION; del PERM; del NODE; del UPDATE