}
}
+ /// Performs checks against necessary constraints after receiving either an `accept_channel` or
+ /// `accept_channel2` message.
+ pub fn do_accept_channel_checks(
+ &mut self, default_limits: &ChannelHandshakeLimits, their_features: &InitFeatures,
+ common_fields: &msgs::CommonAcceptChannelFields, channel_reserve_satoshis: u64,
+ ) -> Result<(), ChannelError> {
+ let peer_limits = if let Some(ref limits) = self.inbound_handshake_limits_override { limits } else { default_limits };
+
+ // Check sanity of message fields:
+ if !self.is_outbound() {
+ return Err(ChannelError::close("Got an accept_channel message from an inbound peer".to_owned()));
+ }
+ if !matches!(self.channel_state, ChannelState::NegotiatingFunding(flags) if flags == NegotiatingFundingFlags::OUR_INIT_SENT) {
+ return Err(ChannelError::close("Got an accept_channel message at a strange time".to_owned()));
+ }
+ if common_fields.dust_limit_satoshis > 21000000 * 100000000 {
+ return Err(ChannelError::close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", common_fields.dust_limit_satoshis)));
+ }
+ if channel_reserve_satoshis > self.channel_value_satoshis {
+ return Err(ChannelError::close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", channel_reserve_satoshis, self.channel_value_satoshis)));
+ }
+ if common_fields.dust_limit_satoshis > self.holder_selected_channel_reserve_satoshis {
+ return Err(ChannelError::close(format!("Dust limit ({}) is bigger than our channel reserve ({})", common_fields.dust_limit_satoshis, self.holder_selected_channel_reserve_satoshis)));
+ }
+ if channel_reserve_satoshis > self.channel_value_satoshis - self.holder_selected_channel_reserve_satoshis {
+ return Err(ChannelError::close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than channel value minus our reserve ({})",
+ channel_reserve_satoshis, self.channel_value_satoshis - self.holder_selected_channel_reserve_satoshis)));
+ }
+ let full_channel_value_msat = (self.channel_value_satoshis - channel_reserve_satoshis) * 1000;
+ if common_fields.htlc_minimum_msat >= full_channel_value_msat {
+ return Err(ChannelError::close(format!("Minimum htlc value ({}) is full channel value ({})", common_fields.htlc_minimum_msat, full_channel_value_msat)));
+ }
+ let max_delay_acceptable = u16::min(peer_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
+ if common_fields.to_self_delay > max_delay_acceptable {
+ return Err(ChannelError::close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_delay_acceptable, common_fields.to_self_delay)));
+ }
+ if common_fields.max_accepted_htlcs < 1 {
+ return Err(ChannelError::close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
+ }
+ if common_fields.max_accepted_htlcs > MAX_HTLCS {
+ return Err(ChannelError::close(format!("max_accepted_htlcs was {}. It must not be larger than {}", common_fields.max_accepted_htlcs, MAX_HTLCS)));
+ }
+
+ // Now check against optional parameters as set by config...
+ if common_fields.htlc_minimum_msat > peer_limits.max_htlc_minimum_msat {
+ return Err(ChannelError::close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", common_fields.htlc_minimum_msat, peer_limits.max_htlc_minimum_msat)));
+ }
+ if common_fields.max_htlc_value_in_flight_msat < peer_limits.min_max_htlc_value_in_flight_msat {
+ return Err(ChannelError::close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", common_fields.max_htlc_value_in_flight_msat, peer_limits.min_max_htlc_value_in_flight_msat)));
+ }
+ if channel_reserve_satoshis > peer_limits.max_channel_reserve_satoshis {
+ return Err(ChannelError::close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", channel_reserve_satoshis, peer_limits.max_channel_reserve_satoshis)));
+ }
+ if common_fields.max_accepted_htlcs < peer_limits.min_max_accepted_htlcs {
+ return Err(ChannelError::close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", common_fields.max_accepted_htlcs, peer_limits.min_max_accepted_htlcs)));
+ }
+ if common_fields.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
+ return Err(ChannelError::close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", common_fields.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
+ }
+ if common_fields.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
+ return Err(ChannelError::close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", common_fields.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
+ }
+ if common_fields.minimum_depth > peer_limits.max_minimum_depth {
+ return Err(ChannelError::close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", peer_limits.max_minimum_depth, common_fields.minimum_depth)));
+ }
+
+ if let Some(ty) = &common_fields.channel_type {
+ if *ty != self.channel_type {
+ return Err(ChannelError::close("Channel Type in accept_channel didn't match the one sent in open_channel.".to_owned()));
+ }
+ } else if their_features.supports_channel_type() {
+ // Assume they've accepted the channel type as they said they understand it.
+ } else {
+ let channel_type = ChannelTypeFeatures::from_init(&their_features);
+ if channel_type != ChannelTypeFeatures::only_static_remote_key() {
+ return Err(ChannelError::close("Only static_remote_key is supported for non-negotiated channel types".to_owned()));
+ }
+ self.channel_type = channel_type.clone();
+ self.channel_transaction_parameters.channel_type_features = channel_type;
+ }
+
+ let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
+ match &common_fields.shutdown_scriptpubkey {
+ &Some(ref script) => {
+ // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
+ if script.len() == 0 {
+ None
+ } else {
+ if !script::is_bolt2_compliant(&script, their_features) {
+ return Err(ChannelError::close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
+ }
+ Some(script.clone())
+ }
+ },
+ // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
+ &None => {
+ return Err(ChannelError::close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
+ }
+ }
+ } else { None };
+
+ self.counterparty_dust_limit_satoshis = common_fields.dust_limit_satoshis;
+ self.counterparty_max_htlc_value_in_flight_msat = cmp::min(common_fields.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
+ self.counterparty_selected_channel_reserve_satoshis = Some(channel_reserve_satoshis);
+ self.counterparty_htlc_minimum_msat = common_fields.htlc_minimum_msat;
+ self.counterparty_max_accepted_htlcs = common_fields.max_accepted_htlcs;
+
+ if peer_limits.trust_own_funding_0conf {
+ self.minimum_depth = Some(common_fields.minimum_depth);
+ } else {
+ self.minimum_depth = Some(cmp::max(1, common_fields.minimum_depth));
+ }
+
+ let counterparty_pubkeys = ChannelPublicKeys {
+ funding_pubkey: common_fields.funding_pubkey,
+ revocation_basepoint: RevocationBasepoint::from(common_fields.revocation_basepoint),
+ payment_point: common_fields.payment_basepoint,
+ delayed_payment_basepoint: DelayedPaymentBasepoint::from(common_fields.delayed_payment_basepoint),
+ htlc_basepoint: HtlcBasepoint::from(common_fields.htlc_basepoint)
+ };
+
+ self.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
+ selected_contest_delay: common_fields.to_self_delay,
+ pubkeys: counterparty_pubkeys,
+ });
+
+ self.counterparty_cur_commitment_point = Some(common_fields.first_per_commitment_point);
+ self.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
+
+ self.channel_state = ChannelState::NegotiatingFunding(
+ NegotiatingFundingFlags::OUR_INIT_SENT | NegotiatingFundingFlags::THEIR_INIT_SENT
+ );
+ self.inbound_handshake_limits_override = None; // We're done enforcing limits on our peer's handshake now.
+
+ Ok(())
+ }
+
/// Returns the block hash in which our funding transaction was confirmed.
pub fn get_funding_tx_confirmed_in(&self) -> Option<BlockHash> {
self.funding_tx_confirmed_in
}
// Message handlers
- pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, default_limits: &ChannelHandshakeLimits, their_features: &InitFeatures) -> Result<(), ChannelError> {
- let peer_limits = if let Some(ref limits) = self.context.inbound_handshake_limits_override { limits } else { default_limits };
-
- // Check sanity of message fields:
- if !self.context.is_outbound() {
- return Err(ChannelError::close("Got an accept_channel message from an inbound peer".to_owned()));
- }
- if !matches!(self.context.channel_state, ChannelState::NegotiatingFunding(flags) if flags == NegotiatingFundingFlags::OUR_INIT_SENT) {
- return Err(ChannelError::close("Got an accept_channel message at a strange time".to_owned()));
- }
- if msg.common_fields.dust_limit_satoshis > 21000000 * 100000000 {
- return Err(ChannelError::close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.common_fields.dust_limit_satoshis)));
- }
- if msg.channel_reserve_satoshis > self.context.channel_value_satoshis {
- return Err(ChannelError::close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.context.channel_value_satoshis)));
- }
- if msg.common_fields.dust_limit_satoshis > self.context.holder_selected_channel_reserve_satoshis {
- return Err(ChannelError::close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.common_fields.dust_limit_satoshis, self.context.holder_selected_channel_reserve_satoshis)));
- }
- if msg.channel_reserve_satoshis > self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis {
- return Err(ChannelError::close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than channel value minus our reserve ({})",
- msg.channel_reserve_satoshis, self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis)));
- }
- let full_channel_value_msat = (self.context.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
- if msg.common_fields.htlc_minimum_msat >= full_channel_value_msat {
- return Err(ChannelError::close(format!("Minimum htlc value ({}) is full channel value ({})", msg.common_fields.htlc_minimum_msat, full_channel_value_msat)));
- }
- let max_delay_acceptable = u16::min(peer_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
- if msg.common_fields.to_self_delay > max_delay_acceptable {
- return Err(ChannelError::close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_delay_acceptable, msg.common_fields.to_self_delay)));
- }
- if msg.common_fields.max_accepted_htlcs < 1 {
- return Err(ChannelError::close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
- }
- if msg.common_fields.max_accepted_htlcs > MAX_HTLCS {
- return Err(ChannelError::close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.common_fields.max_accepted_htlcs, MAX_HTLCS)));
- }
-
- // Now check against optional parameters as set by config...
- if msg.common_fields.htlc_minimum_msat > peer_limits.max_htlc_minimum_msat {
- return Err(ChannelError::close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.common_fields.htlc_minimum_msat, peer_limits.max_htlc_minimum_msat)));
- }
- if msg.common_fields.max_htlc_value_in_flight_msat < peer_limits.min_max_htlc_value_in_flight_msat {
- return Err(ChannelError::close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.common_fields.max_htlc_value_in_flight_msat, peer_limits.min_max_htlc_value_in_flight_msat)));
- }
- if msg.channel_reserve_satoshis > peer_limits.max_channel_reserve_satoshis {
- return Err(ChannelError::close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, peer_limits.max_channel_reserve_satoshis)));
- }
- if msg.common_fields.max_accepted_htlcs < peer_limits.min_max_accepted_htlcs {
- return Err(ChannelError::close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.common_fields.max_accepted_htlcs, peer_limits.min_max_accepted_htlcs)));
- }
- if msg.common_fields.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
- return Err(ChannelError::close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.common_fields.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
- }
- if msg.common_fields.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
- return Err(ChannelError::close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.common_fields.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
- }
- if msg.common_fields.minimum_depth > peer_limits.max_minimum_depth {
- return Err(ChannelError::close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", peer_limits.max_minimum_depth, msg.common_fields.minimum_depth)));
- }
-
- if let Some(ty) = &msg.common_fields.channel_type {
- if *ty != self.context.channel_type {
- return Err(ChannelError::close("Channel Type in accept_channel didn't match the one sent in open_channel.".to_owned()));
- }
- } else if their_features.supports_channel_type() {
- // Assume they've accepted the channel type as they said they understand it.
- } else {
- let channel_type = ChannelTypeFeatures::from_init(&their_features);
- if channel_type != ChannelTypeFeatures::only_static_remote_key() {
- return Err(ChannelError::close("Only static_remote_key is supported for non-negotiated channel types".to_owned()));
- }
- self.context.channel_type = channel_type.clone();
- self.context.channel_transaction_parameters.channel_type_features = channel_type;
- }
-
- let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
- match &msg.common_fields.shutdown_scriptpubkey {
- &Some(ref script) => {
- // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
- if script.len() == 0 {
- None
- } else {
- if !script::is_bolt2_compliant(&script, their_features) {
- return Err(ChannelError::close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
- }
- Some(script.clone())
- }
- },
- // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
- &None => {
- return Err(ChannelError::close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
- }
- }
- } else { None };
-
- self.context.counterparty_dust_limit_satoshis = msg.common_fields.dust_limit_satoshis;
- self.context.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.common_fields.max_htlc_value_in_flight_msat, self.context.channel_value_satoshis * 1000);
- self.context.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
- self.context.counterparty_htlc_minimum_msat = msg.common_fields.htlc_minimum_msat;
- self.context.counterparty_max_accepted_htlcs = msg.common_fields.max_accepted_htlcs;
-
- if peer_limits.trust_own_funding_0conf {
- self.context.minimum_depth = Some(msg.common_fields.minimum_depth);
- } else {
- self.context.minimum_depth = Some(cmp::max(1, msg.common_fields.minimum_depth));
- }
-
- let counterparty_pubkeys = ChannelPublicKeys {
- funding_pubkey: msg.common_fields.funding_pubkey,
- revocation_basepoint: RevocationBasepoint::from(msg.common_fields.revocation_basepoint),
- payment_point: msg.common_fields.payment_basepoint,
- delayed_payment_basepoint: DelayedPaymentBasepoint::from(msg.common_fields.delayed_payment_basepoint),
- htlc_basepoint: HtlcBasepoint::from(msg.common_fields.htlc_basepoint)
- };
-
- self.context.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
- selected_contest_delay: msg.common_fields.to_self_delay,
- pubkeys: counterparty_pubkeys,
- });
-
- self.context.counterparty_cur_commitment_point = Some(msg.common_fields.first_per_commitment_point);
- self.context.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
-
- self.context.channel_state = ChannelState::NegotiatingFunding(
- NegotiatingFundingFlags::OUR_INIT_SENT | NegotiatingFundingFlags::THEIR_INIT_SENT
- );
- self.context.inbound_handshake_limits_override = None; // We're done enforcing limits on our peer's handshake now.
-
- Ok(())
+ pub fn accept_channel(
+ &mut self, msg: &msgs::AcceptChannel, default_limits: &ChannelHandshakeLimits,
+ their_features: &InitFeatures
+ ) -> Result<(), ChannelError> {
+ self.context.do_accept_channel_checks(default_limits, their_features, &msg.common_fields, msg.channel_reserve_satoshis)
}
/// Handles a funding_signed message from the remote end.
projects / rust-lightning / commitdiff