lnpeer: follow-up OPTION_SUPPORT_LARGE_CHANNEL

follow-up 40f2087ac3

electrum/lnpeer.py

@@ -603,9 +603,6 @@ class Peer(Logger):
     def is_shutdown_anysegwit(self):
         return self.features.supports(LnFeatures.OPTION_SHUTDOWN_ANYSEGWIT_OPT)
 
-    def supports_large_channels(self):
-        return self.features.supports(LnFeatures.OPTION_SUPPORT_LARGE_CHANNELS)
-
     def is_channel_type(self):
         return self.features.supports(LnFeatures.OPTION_CHANNEL_TYPE_OPT)
 
@@ -662,7 +659,7 @@ class Peer(Logger):
             current_htlc_signatures=b'',
             htlc_minimum_msat=1,
         )
-        local_config.validate_params(funding_sat=funding_sat)
+        local_config.validate_params(funding_sat=funding_sat, config=self.network.config, peer_features=self.features)
         return local_config
 
     def temporarily_reserve_funding_tx_change_address(func):
@@ -807,6 +804,8 @@ class Peer(Logger):
             funding_sat=funding_sat,
             is_local_initiator=True,
             initial_feerate_per_kw=feerate,
+            config=self.network.config,
+            peer_features=self.features,
         )
 
         # -> funding created
@@ -967,6 +966,8 @@ class Peer(Logger):
             funding_sat=funding_sat,
             is_local_initiator=False,
             initial_feerate_per_kw=feerate,
+            config=self.network.config,
+            peer_features=self.features,
         )
 
         # note: we ignore payload['channel_flags'],  which e.g. contains 'announce_channel'.

electrum/lnutil.py

@@ -38,6 +38,7 @@ if TYPE_CHECKING:
     from .lnchannel import Channel, AbstractChannel
     from .lnrouter import LNPaymentRoute
     from .lnonion import OnionRoutingFailure
+    from .simple_config import SimpleConfig
 
 
 _logger = get_logger(__name__)
@@ -49,6 +50,7 @@ HTLC_SUCCESS_WEIGHT = 703
 COMMITMENT_TX_WEIGHT = 724
 HTLC_OUTPUT_WEIGHT = 172
 
+LN_MAX_FUNDING_SAT_LEGACY = pow(2, 24) - 1
 DUST_LIMIT_MAX = 1000
 
 # dummy address for fee estimation of funding tx
@@ -92,7 +94,7 @@ class ChannelConfig(StoredObject):
     htlc_minimum_msat = attr.ib(type=int)  # smallest value for INCOMING htlc
     upfront_shutdown_script = attr.ib(type=bytes, converter=hex_to_bytes)
 
-    def validate_params(self, *, funding_sat: int) -> None:
+    def validate_params(self, *, funding_sat: int, config: 'SimpleConfig', peer_features: 'LnFeatures') -> None:
         conf_name = type(self).__name__
         for key in (
                 self.payment_basepoint,
@@ -105,6 +107,12 @@ class ChannelConfig(StoredObject):
                 raise Exception(f"{conf_name}. invalid pubkey in channel config")
         if funding_sat < MIN_FUNDING_SAT:
             raise Exception(f"funding_sat too low: {funding_sat} sat < {MIN_FUNDING_SAT}")
+        if not peer_features.supports(LnFeatures.OPTION_SUPPORT_LARGE_CHANNEL_OPT):
+            # MUST set funding_satoshis to less than 2^24 satoshi
+            if funding_sat > LN_MAX_FUNDING_SAT_LEGACY:
+                raise Exception(f"funding_sat too high: {funding_sat} sat > {LN_MAX_FUNDING_SAT_LEGACY} (legacy limit)")
+        if funding_sat > config.LIGHTNING_MAX_FUNDING_SAT:
+            raise Exception(f"funding_sat too high: {funding_sat} sat > {config.LIGHTNING_MAX_FUNDING_SAT} (config setting)")
         # MUST set push_msat to equal or less than 1000 * funding_satoshis
         if not (0 <= self.initial_msat <= 1000 * funding_sat):
             raise Exception(f"{conf_name}. insane initial_msat={self.initial_msat}. (funding_sat={funding_sat})")
@@ -139,10 +147,12 @@ class ChannelConfig(StoredObject):
             funding_sat: int,
             is_local_initiator: bool,  # whether we are the funder
             initial_feerate_per_kw: int,
+            config: 'SimpleConfig',
+            peer_features: 'LnFeatures',
     ) -> None:
         # first we validate the configs separately
-        local_config.validate_params(funding_sat=funding_sat)
+        local_config.validate_params(funding_sat=funding_sat, config=config, peer_features=peer_features)
-        remote_config.validate_params(funding_sat=funding_sat)
+        remote_config.validate_params(funding_sat=funding_sat, config=config, peer_features=peer_features)
         # now do tests that need access to both configs
         if is_local_initiator:
             funder, fundee = LOCAL, REMOTE
@@ -209,10 +219,10 @@ class LocalConfig(ChannelConfig):
             kwargs['payment_basepoint'] = keypair_generator(LnKeyFamily.PAYMENT_BASE)
         return LocalConfig(**kwargs)
 
-    def validate_params(self, *, funding_sat: int) -> None:
+    def validate_params(self, *, funding_sat: int, config: 'SimpleConfig', peer_features: 'LnFeatures') -> None:
         conf_name = type(self).__name__
         # run base checks regardless whether LOCAL/REMOTE config
-        super().validate_params(funding_sat=funding_sat)
+        super().validate_params(funding_sat=funding_sat, config=config, peer_features=peer_features)
         # run some stricter checks on LOCAL config (make sure we ourselves do the sane thing,
         # even if we are lenient with REMOTE for compatibility reasons)
         HTLC_MINIMUM_MSAT_MIN = 1

electrum/simple_config.py

@@ -18,6 +18,7 @@ from . import invoices
 from .util import base_units, base_unit_name_to_decimal_point, decimal_point_to_base_unit_name, UnknownBaseUnit, DECIMAL_POINT_DEFAULT
 from .util import format_satoshis, format_fee_satoshis, os_chmod
 from .util import user_dir, make_dir, NoDynamicFeeEstimates, quantize_feerate
+from .lnutil import LN_MAX_FUNDING_SAT_LEGACY
 from .i18n import _
 from .logging import get_logger, Logger
 
@@ -888,7 +889,7 @@ class SimpleConfig(Logger):
     LIGHTNING_USE_RECOVERABLE_CHANNELS = ConfigVar('use_recoverable_channels', default=True, type_=bool)
     LIGHTNING_ALLOW_INSTANT_SWAPS = ConfigVar('allow_instant_swaps', default=False, type_=bool)
     LIGHTNING_TO_SELF_DELAY_CSV = ConfigVar('lightning_to_self_delay', default=7 * 144, type_=int)
-    LIGHTNING_MAX_FUNDING_SAT = ConfigVar('lightning_max_funding_sat', default=pow(2, 24) - 1, type_=int)
+    LIGHTNING_MAX_FUNDING_SAT = ConfigVar('lightning_max_funding_sat', default=LN_MAX_FUNDING_SAT_LEGACY, type_=int)
 
     EXPERIMENTAL_LN_FORWARD_PAYMENTS = ConfigVar('lightning_forward_payments', default=False, type_=bool)
     EXPERIMENTAL_LN_FORWARD_TRAMPOLINE_PAYMENTS = ConfigVar('lightning_forward_trampoline_payments', default=False, type_=bool)