From: Yuntai Kyong Date: Tue, 14 Aug 2018 16:12:40 +0000 (+0900) Subject: Add various checking when handling open and accept X-Git-Tag: v0.0.12~347^2~4 X-Git-Url: http://git.bitcoin.ninja/?a=commitdiff_plain;h=0fece38b19e78c390916dfc44a9192c52573db98;p=rust-lightning Add various checking when handling open and accept Add `derive_minimum_depth()` and `derive_maximum_minimum_depth()` and hide CONF_TARGET constant behind these functions. Replace `DisconnectPeer` error with `HandleError` with `ErrorAction::SendErrorMessage` --- diff --git a/src/ln/channel.rs b/src/ln/channel.rs index c88e1d776..93e164809 100644 --- a/src/ln/channel.rs +++ b/src/ln/channel.rs @@ -320,7 +320,6 @@ pub struct Channel { } const OUR_MAX_HTLCS: u16 = 5; //TODO -const CONF_TARGET: u32 = 12; //TODO: Should be much higher /// Confirmation count threshold at which we close a channel. Ideally we'd keep the channel around /// on ice until the funding transaction gets more confirmations, but the LN protocol doesn't /// really allow for this, so instead we're stuck closing it out at that point. @@ -372,6 +371,16 @@ impl Channel { 1000 // TODO } + fn derive_minimum_depth(_channel_value_satoshis_msat: u64, _value_to_self_msat: u64) -> u32 { + const CONF_TARGET: u32 = 12; //TODO: Should be much higher + CONF_TARGET + } + + fn derive_maximum_minimum_depth(_channel_value_satoshis_msat: u64, _value_to_self_msat: u64) -> u32 { + const CONF_TARGET: u32 = 12; //TODO: Should be much higher + CONF_TARGET * 2 + } + // Constructors: pub fn new_outbound(fee_estimator: &FeeEstimator, chan_keys: ChannelKeys, their_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, announce_publicly: bool, user_id: u64, logger: Arc) -> Result { if channel_value_satoshis >= MAX_FUNDING_SATOSHIS { @@ -465,31 +474,46 @@ impl Channel { /// Generally prefers to take the DisconnectPeer action on failure, as a notice to the sender /// that we're rejecting the new channel. pub fn new_from_req(fee_estimator: &FeeEstimator, chan_keys: ChannelKeys, their_node_id: PublicKey, msg: &msgs::OpenChannel, user_id: u64, require_announce: bool, allow_announce: bool, logger: Arc) -> Result { + macro_rules! return_error_message { + ( $msg: expr ) => { + return Err(HandleError{err: $msg, action: Some(msgs::ErrorAction::SendErrorMessage{ msg: msgs::ErrorMessage { channel_id: msg.temporary_channel_id, data: $msg.to_string() }})}); + } + } + // Check sanity of message fields: if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS { - return Err(HandleError{err: "funding value > 2^24", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}); + return_error_message!("funding value > 2^24"); } if msg.channel_reserve_satoshis > msg.funding_satoshis { - return Err(HandleError{err: "Bogus channel_reserve_satoshis", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}); + return_error_message!("Bogus channel_reserve_satoshis"); } if msg.push_msat > (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000 { - return Err(HandleError{err: "push_msat more than highest possible value", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}); + return_error_message!("push_msat larger than funding value"); } if msg.dust_limit_satoshis > msg.funding_satoshis { - return Err(HandleError{err: "Peer never wants payout outputs?", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}); + return_error_message!("Peer never wants payout outputs?"); + } + if msg.dust_limit_satoshis > msg.channel_reserve_satoshis { + return_error_message!("Bogus; channel reserve is less than dust limit"); } if msg.htlc_minimum_msat >= (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000 { - return Err(HandleError{err: "Minimum htlc value is full channel value", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}); + return_error_message!("Miminum htlc value is full channel value"); } - Channel::check_remote_fee(fee_estimator, msg.feerate_per_kw)?; + Channel::check_remote_fee(fee_estimator, msg.feerate_per_kw).map_err(|e| + HandleError{err: e.err, action: Some(msgs::ErrorAction::SendErrorMessage{ msg: msgs::ErrorMessage { channel_id: msg.temporary_channel_id, data: e.err.to_string() }})} + )?; + if msg.to_self_delay > MAX_LOCAL_BREAKDOWN_TIMEOUT { - return Err(HandleError{err: "They wanted our payments to be delayed by a needlessly long period", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}); + return_error_message!("They wanted our payments to be delayed by a needlessly long period"); } if msg.max_accepted_htlcs < 1 { - return Err(HandleError{err: "0 max_accpted_htlcs makes for a useless channel", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}); + return_error_message!("0 max_accpted_htlcs makes for a useless channel"); + } + if msg.max_accepted_htlcs > 483 { + return_error_message!("max_accpted_htlcs > 483"); } if (msg.channel_flags & 254) != 0 { - return Err(HandleError{err: "unknown channel_flags", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}); + return Err(HandleError{err: "Unknown channel flags", action: Some(msgs::ErrorAction::IgnoreError) }); } // Convert things into internal flags and prep our state: @@ -504,6 +528,31 @@ impl Channel { let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background); + let our_dust_limit_satoshis = Channel::derive_our_dust_limit_satoshis(background_feerate); + let our_channel_reserve_satoshis = Channel::get_our_channel_reserve_satoshis(msg.funding_satoshis); + if our_channel_reserve_satoshis < our_dust_limit_satoshis { + return_error_message!("Suitalbe channel reserve not found. aborting"); + } + if msg.channel_reserve_satoshis < our_dust_limit_satoshis { + return_error_message!("channel_reserve_satoshis too small"); + } + if our_channel_reserve_satoshis < msg.dust_limit_satoshis { + return_error_message!("Dust limit too high for our channel reserve"); + } + + // check if the funder's amount for the initial commitment tx is sufficient + // for full fee payment + let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat; + if funders_amount_msat < background_feerate * COMMITMENT_TX_BASE_WEIGHT { + return_error_message!("Insufficient funding amount for initial commitment"); + } + + let to_local_msat = msg.push_msat; + let to_remote_msat = funders_amount_msat - background_feerate * COMMITMENT_TX_BASE_WEIGHT; + if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= our_channel_reserve_satoshis * 1000 { + return_error_message!("Insufficient funding amount for initial commitment"); + } + let secp_ctx = Secp256k1::new(); let our_channel_monitor_claim_key_hash = Hash160::from_data(&PublicKey::from_secret_key(&secp_ctx, &chan_keys.channel_monitor_claim_key).unwrap().serialize()); let our_channel_monitor_claim_script = Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&our_channel_monitor_claim_key_hash[..]).into_script(); @@ -545,7 +594,7 @@ impl Channel { feerate_per_kw: msg.feerate_per_kw as u64, channel_value_satoshis: msg.funding_satoshis, their_dust_limit_satoshis: msg.dust_limit_satoshis, - our_dust_limit_satoshis: Channel::derive_our_dust_limit_satoshis(background_feerate), + our_dust_limit_satoshis: our_dust_limit_satoshis, their_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000), their_channel_reserve_satoshis: msg.channel_reserve_satoshis, their_htlc_minimum_msat: msg.htlc_minimum_msat, @@ -1118,28 +1167,47 @@ impl Channel { // Message handlers: pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel) -> Result<(), HandleError> { + macro_rules! return_error_message { + ( $msg: expr ) => { + return Err(HandleError{err: $msg, action: Some(msgs::ErrorAction::SendErrorMessage{ msg: msgs::ErrorMessage { channel_id: msg.temporary_channel_id, data: $msg.to_string() }})}); + } + } // Check sanity of message fields: if !self.channel_outbound { - return Err(HandleError{err: "Got an accept_channel message from an inbound peer", action: None}); + return_error_message!("Got an accept_channel message from an inbound peer"); } if self.channel_state != ChannelState::OurInitSent as u32 { - return Err(HandleError{err: "Got an accept_channel message at a strange time", action: None}); + return_error_message!("Got an accept_channel message at a strange time"); } if msg.dust_limit_satoshis > 21000000 * 100000000 { - return Err(HandleError{err: "Peer never wants payout outputs?", action: None}); + return_error_message!("Peer never wants payout outputs?"); } if msg.channel_reserve_satoshis > self.channel_value_satoshis { - return Err(HandleError{err: "Bogus channel_reserve_satoshis", action: None}); + return_error_message!("Bogus channel_reserve_satoshis"); + } + if msg.dust_limit_satoshis > msg.channel_reserve_satoshis { + return_error_message!("Bogus channel_reserve and dust_limit"); + } + if msg.channel_reserve_satoshis < self.our_dust_limit_satoshis { + return_error_message!("Peer never wants payout outputs?"); + } + if msg.dust_limit_satoshis > Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis) { + return_error_message!("Dust limit is bigger than our channel reverse"); } if msg.htlc_minimum_msat >= (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000 { - return Err(HandleError{err: "Minimum htlc value is full channel value", action: None}); + return_error_message!("Minimum htlc value is full channel value"); + } + if msg.minimum_depth > Channel::derive_maximum_minimum_depth(self.channel_value_satoshis*1000, self.value_to_self_msat) { + return_error_message!("minimum_depth too large"); } - //TODO do something with minimum_depth if msg.to_self_delay > MAX_LOCAL_BREAKDOWN_TIMEOUT { - return Err(HandleError{err: "They wanted our payments to be delayed by a needlessly long period", action: None}); + return_error_message!("They wanted our payments to be delayed by a needlessly long period"); } if msg.max_accepted_htlcs < 1 { - return Err(HandleError{err: "0 max_accpted_htlcs makes for a useless channel", action: None}); + return_error_message!("0 max_accpted_htlcs makes for a useless channel"); + } + if msg.max_accepted_htlcs > 483 { + return_error_message!("max_accpted_htlcs > 483"); } self.channel_monitor.set_their_htlc_base_key(&msg.htlc_basepoint); @@ -1958,7 +2026,7 @@ impl Channel { if header.bitcoin_hash() != self.last_block_connected { self.last_block_connected = header.bitcoin_hash(); self.funding_tx_confirmations += 1; - if self.funding_tx_confirmations == CONF_TARGET as u64 { + if self.funding_tx_confirmations == Channel::derive_minimum_depth(self.channel_value_satoshis*1000, self.value_to_self_msat) as u64 { let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 { self.channel_state |= ChannelState::OurFundingLocked as u32; true @@ -2026,7 +2094,7 @@ impl Channel { } } if Some(header.bitcoin_hash()) == self.funding_tx_confirmed_in { - self.funding_tx_confirmations = CONF_TARGET as u64 - 1; + self.funding_tx_confirmations = Channel::derive_minimum_depth(self.channel_value_satoshis*1000, self.value_to_self_msat) as u64 - 1; } false } @@ -2090,7 +2158,7 @@ impl Channel { max_htlc_value_in_flight_msat: Channel::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis), channel_reserve_satoshis: Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis), htlc_minimum_msat: self.our_htlc_minimum_msat, - minimum_depth: CONF_TARGET, + minimum_depth: Channel::derive_minimum_depth(self.channel_value_satoshis*1000, self.value_to_self_msat), to_self_delay: BREAKDOWN_TIMEOUT, max_accepted_htlcs: OUR_MAX_HTLCS, funding_pubkey: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key).unwrap(),