X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchannel.rs;h=c05ca2a8f16656dd03a3ca2fb531859175b71a39;hb=99eef23f4ef0c53e2b047261a4495d2c2f7bbe20;hp=8d55804f41d62a8c83825f1dc7b02df8f52a10c9;hpb=2087032e7a823f6c63a64dac951e0f4843bc4667;p=rust-lightning diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs index 8d55804f..c05ca2a8 100644 --- a/lightning/src/ln/channel.rs +++ b/lightning/src/ln/channel.rs @@ -34,6 +34,7 @@ use std; use std::default::Default; use std::{cmp,mem,fmt}; use std::ops::Deref; +use bitcoin::hashes::hex::ToHex; #[cfg(test)] pub struct ChannelValueStat { @@ -44,6 +45,7 @@ pub struct ChannelValueStat { pub pending_inbound_htlcs_amount_msat: u64, pub holding_cell_outbound_amount_msat: u64, pub their_max_htlc_value_in_flight_msat: u64, // outgoing + pub their_dust_limit_msat: u64, } enum InboundHTLCRemovalReason { @@ -53,19 +55,43 @@ enum InboundHTLCRemovalReason { } enum InboundHTLCState { - /// Added by remote, to be included in next local commitment tx. + /// Offered by remote, to be included in next local commitment tx. I.e., the remote sent an + /// update_add_htlc message for this HTLC. RemoteAnnounced(PendingHTLCStatus), - /// Included in a received commitment_signed message (implying we've revoke_and_ack'ed it), but - /// the remote side hasn't yet revoked their previous state, which we need them to do before we - /// accept this HTLC. Implies AwaitingRemoteRevoke. - /// We also have not yet included this HTLC in a commitment_signed message, and are waiting on - /// a remote revoke_and_ack on a previous state before we can do so. + /// Included in a received commitment_signed message (implying we've + /// revoke_and_ack'd it), but the remote hasn't yet revoked their previous + /// state (see the example below). We have not yet included this HTLC in a + /// commitment_signed message because we are waiting on the remote's + /// aforementioned state revocation. One reason this missing remote RAA + /// (revoke_and_ack) blocks us from constructing a commitment_signed message + /// is because every time we create a new "state", i.e. every time we sign a + /// new commitment tx (see [BOLT #2]), we need a new per_commitment_point, + /// which are provided one-at-a-time in each RAA. E.g., the last RAA they + /// sent provided the per_commitment_point for our current commitment tx. + /// The other reason we should not send a commitment_signed without their RAA + /// is because their RAA serves to ACK our previous commitment_signed. + /// + /// Here's an example of how an HTLC could come to be in this state: + /// remote --> update_add_htlc(prev_htlc) --> local + /// remote --> commitment_signed(prev_htlc) --> local + /// remote <-- revoke_and_ack <-- local + /// remote <-- commitment_signed(prev_htlc) <-- local + /// [note that here, the remote does not respond with a RAA] + /// remote --> update_add_htlc(this_htlc) --> local + /// remote --> commitment_signed(prev_htlc, this_htlc) --> local + /// Now `this_htlc` will be assigned this state. It's unable to be officially + /// accepted, i.e. included in a commitment_signed, because we're missing the + /// RAA that provides our next per_commitment_point. The per_commitment_point + /// is used to derive commitment keys, which are used to construct the + /// signatures in a commitment_signed message. + /// Implies AwaitingRemoteRevoke. + /// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus), - /// Included in a received commitment_signed message (implying we've revoke_and_ack'ed it), but - /// the remote side hasn't yet revoked their previous state, which we need them to do before we - /// accept this HTLC. Implies AwaitingRemoteRevoke. - /// We have included this HTLC in our latest commitment_signed and are now just waiting on a - /// revoke_and_ack. + /// Included in a received commitment_signed message (implying we've revoke_and_ack'd it). + /// We have also included this HTLC in our latest commitment_signed and are now just waiting + /// on the remote's revoke_and_ack to make this HTLC an irrevocable part of the state of the + /// channel (before it can then get forwarded and/or removed). + /// Implies AwaitingRemoteRevoke. AwaitingAnnouncedRemoteRevoke(PendingHTLCStatus), Committed, /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we @@ -159,9 +185,9 @@ enum HTLCUpdateAwaitingACK { /// move on to ShutdownComplete, at which point most calls into this channel are disallowed. enum ChannelState { /// Implies we have (or are prepared to) send our open_channel/accept_channel message - OurInitSent = (1 << 0), + OurInitSent = 1 << 0, /// Implies we have received their open_channel/accept_channel message - TheirInitSent = (1 << 1), + TheirInitSent = 1 << 1, /// We have sent funding_created and are awaiting a funding_signed to advance to FundingSent. /// Note that this is nonsense for an inbound channel as we immediately generate funding_signed /// upon receipt of funding_created, so simply skip this state. @@ -172,35 +198,35 @@ enum ChannelState { FundingSent = 8, /// Flag which can be set on FundingSent to indicate they sent us a funding_locked message. /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded. - TheirFundingLocked = (1 << 4), + TheirFundingLocked = 1 << 4, /// Flag which can be set on FundingSent to indicate we sent them a funding_locked message. /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded. - OurFundingLocked = (1 << 5), + OurFundingLocked = 1 << 5, ChannelFunded = 64, /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered /// "disconnected" and no updates are allowed until after we've done a channel_reestablish /// dance. - PeerDisconnected = (1 << 7), + PeerDisconnected = 1 << 7, /// Flag which is set on ChannelFunded, FundingCreated, and FundingSent indicating the user has /// told us they failed to update our ChannelMonitor somewhere and we should pause sending any /// outbound messages until they've managed to do so. - MonitorUpdateFailed = (1 << 8), + MonitorUpdateFailed = 1 << 8, /// Flag which implies that we have sent a commitment_signed but are awaiting the responding /// revoke_and_ack message. During this time period, we can't generate new commitment_signed /// messages as then we will be unable to determine which HTLCs they included in their /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent /// later. /// Flag is set on ChannelFunded. - AwaitingRemoteRevoke = (1 << 9), + AwaitingRemoteRevoke = 1 << 9, /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected /// to respond with our own shutdown message when possible. - RemoteShutdownSent = (1 << 10), + RemoteShutdownSent = 1 << 10, /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this /// point, we may not add any new HTLCs to the channel. /// TODO: Investigate some kind of timeout mechanism by which point the remote end must provide /// us their shutdown. - LocalShutdownSent = (1 << 11), + LocalShutdownSent = 1 << 11, /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about /// to drop us, but we store this anyway. ShutdownComplete = 4096, @@ -285,16 +311,16 @@ pub(super) struct Channel { // revoke_and_ack is received and new commitment_signed is generated to be // sent to the funder. Otherwise, the pending value is removed when receiving // commitment_signed. - pending_update_fee: Option, + pending_update_fee: Option, // update_fee() during ChannelState::AwaitingRemoteRevoke is hold in // holdina_cell_update_fee then moved to pending_udpate_fee when revoke_and_ack // is received. holding_cell_update_fee is updated when there are additional // update_fee() during ChannelState::AwaitingRemoteRevoke. - holding_cell_update_fee: Option, + holding_cell_update_fee: Option, next_local_htlc_id: u64, next_remote_htlc_id: u64, update_time_counter: u32, - feerate_per_kw: u64, + feerate_per_kw: u32, #[cfg(debug_assertions)] /// Max to_local and to_remote outputs in a locally-generated commitment transaction @@ -303,7 +329,7 @@ pub(super) struct Channel { /// Max to_local and to_remote outputs in a remote-generated commitment transaction max_commitment_tx_output_remote: ::std::sync::Mutex<(u64, u64)>, - last_sent_closing_fee: Option<(u64, u64, Signature)>, // (feerate, fee, our_sig) + last_sent_closing_fee: Option<(u32, u64, Signature)>, // (feerate, fee, our_sig) funding_txo: Option, @@ -384,17 +410,17 @@ pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24; /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our /// channel_id in ChannelManager. pub(super) enum ChannelError { - Ignore(&'static str), - Close(&'static str), - CloseDelayBroadcast(&'static str), + Ignore(String), + Close(String), + CloseDelayBroadcast(String), } impl fmt::Debug for ChannelError { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { match self { - &ChannelError::Ignore(e) => write!(f, "Ignore : {}", e), - &ChannelError::Close(e) => write!(f, "Close : {}", e), - &ChannelError::CloseDelayBroadcast(e) => write!(f, "CloseDelayBroadcast : {}", e) + &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e), + &ChannelError::Close(ref e) => write!(f, "Close : {}", e), + &ChannelError::CloseDelayBroadcast(ref e) => write!(f, "CloseDelayBroadcast : {}", e) } } } @@ -423,8 +449,8 @@ impl Channel { cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO } - fn derive_our_dust_limit_satoshis(at_open_background_feerate: u64) -> u64 { - cmp::max(at_open_background_feerate * B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT / 1000, 546) //TODO + fn derive_our_dust_limit_satoshis(at_open_background_feerate: u32) -> u64 { + cmp::max(at_open_background_feerate as u64 * B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT / 1000, 546) //TODO } // Constructors: @@ -432,20 +458,19 @@ impl Channel { where K::Target: KeysInterface, F::Target: FeeEstimator, { + let our_to_self_delay = config.own_channel_config.our_to_self_delay; let chan_keys = keys_provider.get_channel_keys(false, channel_value_satoshis); if channel_value_satoshis >= MAX_FUNDING_SATOSHIS { - return Err(APIError::APIMisuseError{err: "funding value > 2^24"}); + return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than {}, it was {}", MAX_FUNDING_SATOSHIS, channel_value_satoshis)}); } - - if push_msat > channel_value_satoshis * 1000 { - return Err(APIError::APIMisuseError{err: "push value > channel value"}); + let channel_value_msat = channel_value_satoshis * 1000; + if push_msat > channel_value_msat { + return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) }); } - if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT { - return Err(APIError::APIMisuseError{err: "Configured with an unreasonable our_to_self_delay putting user funds at risks"}); + if our_to_self_delay < BREAKDOWN_TIMEOUT { + return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", our_to_self_delay)}); } - - let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background); if Channel::::get_remote_channel_reserve_satoshis(channel_value_satoshis) < Channel::::derive_our_dust_limit_satoshis(background_feerate) { return Err(APIError::FeeRateTooHigh{err: format!("Not enough reserve above dust limit can be found at current fee rate({})", background_feerate), feerate: background_feerate}); @@ -511,7 +536,7 @@ impl Channel { their_htlc_minimum_msat: 0, our_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat }, their_to_self_delay: 0, - our_to_self_delay: config.own_channel_config.our_to_self_delay, + our_to_self_delay, their_max_accepted_htlcs: 0, minimum_depth: 0, // Filled in in accept_channel @@ -533,11 +558,13 @@ impl Channel { fn check_remote_fee(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError> where F::Target: FeeEstimator { - if (feerate_per_kw as u64) < fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) { - return Err(ChannelError::Close("Peer's feerate much too low")); + let lower_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background); + if feerate_per_kw < lower_limit { + return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit))); } - if (feerate_per_kw as u64) > fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) * 2 { - return Err(ChannelError::Close("Peer's feerate much too high")); + let upper_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64 * 2; + if feerate_per_kw as u64 > upper_limit { + return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit))); } Ok(()) } @@ -556,65 +583,68 @@ impl Channel { delayed_payment_basepoint: msg.delayed_payment_basepoint, htlc_basepoint: msg.htlc_basepoint }; - chan_keys.set_remote_channel_pubkeys(&their_pubkeys); + chan_keys.on_accept(&their_pubkeys, msg.to_self_delay, config.own_channel_config.our_to_self_delay); let mut local_config = (*config).channel_options.clone(); if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT { - return Err(ChannelError::Close("Configured with an unreasonable our_to_self_delay putting user funds at risks")); + return Err(ChannelError::Close(format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks. It must be greater than {}", config.own_channel_config.our_to_self_delay, BREAKDOWN_TIMEOUT))); } // Check sanity of message fields: if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS { - return Err(ChannelError::Close("funding value > 2^24")); + return Err(ChannelError::Close(format!("Funding must be smaller than {}. It was {}", MAX_FUNDING_SATOSHIS, msg.funding_satoshis))); } if msg.channel_reserve_satoshis > msg.funding_satoshis { - return Err(ChannelError::Close("Bogus channel_reserve_satoshis")); + return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis))); } - if msg.push_msat > (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000 { - return Err(ChannelError::Close("push_msat larger than funding value")); + let funding_value = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000; + if msg.push_msat > funding_value { + return Err(ChannelError::Close(format!("push_msat {} was larger than funding value {}", msg.push_msat, funding_value))); } if msg.dust_limit_satoshis > msg.funding_satoshis { - return Err(ChannelError::Close("Peer never wants payout outputs?")); + return Err(ChannelError::Close(format!("dust_limit_satoshis {} was larger than funding_satoshis {}. Peer never wants payout outputs?", msg.dust_limit_satoshis, msg.funding_satoshis))); } if msg.dust_limit_satoshis > msg.channel_reserve_satoshis { - return Err(ChannelError::Close("Bogus; channel reserve is less than dust limit")); + return Err(ChannelError::Close(format!("Bogus; channel reserve ({}) is less than dust limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis))); } - if msg.htlc_minimum_msat >= (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000 { - return Err(ChannelError::Close("Minimum htlc value is full channel value")); + let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000; + if msg.htlc_minimum_msat >= full_channel_value_msat { + return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat))); } Channel::::check_remote_fee(fee_estimator, msg.feerate_per_kw)?; - if msg.to_self_delay > config.peer_channel_config_limits.their_to_self_delay || msg.to_self_delay > MAX_LOCAL_BREAKDOWN_TIMEOUT { - return Err(ChannelError::Close("They wanted our payments to be delayed by a needlessly long period")); + let max_to_self_delay = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT); + if msg.to_self_delay > max_to_self_delay { + return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_to_self_delay, msg.to_self_delay))); } if msg.max_accepted_htlcs < 1 { - return Err(ChannelError::Close("0 max_accpted_htlcs makes for a useless channel")); + return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned())); } if msg.max_accepted_htlcs > 483 { - return Err(ChannelError::Close("max_accpted_htlcs > 483")); + return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than 483", msg.max_accepted_htlcs))); } // Now check against optional parameters as set by config... if msg.funding_satoshis < config.peer_channel_config_limits.min_funding_satoshis { - return Err(ChannelError::Close("funding satoshis is less than the user specified limit")); + return Err(ChannelError::Close(format!("Funding satoshis ({}) is less than the user specified limit ({})", msg.funding_satoshis, config.peer_channel_config_limits.min_funding_satoshis))); } if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat { - return Err(ChannelError::Close("htlc minimum msat is higher than the user specified limit")); + return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, config.peer_channel_config_limits.max_htlc_minimum_msat))); } if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat { - return Err(ChannelError::Close("max htlc value in flight msat is less than the user specified limit")); + return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat))); } if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis { - return Err(ChannelError::Close("channel reserve satoshis is higher than the user specified limit")); + return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, config.peer_channel_config_limits.max_channel_reserve_satoshis))); } if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs { - return Err(ChannelError::Close("max accepted htlcs is less than the user specified limit")); + return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.peer_channel_config_limits.min_max_accepted_htlcs))); } if msg.dust_limit_satoshis < config.peer_channel_config_limits.min_dust_limit_satoshis { - return Err(ChannelError::Close("dust limit satoshis is less than the user specified limit")); + return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.min_dust_limit_satoshis))); } if msg.dust_limit_satoshis > config.peer_channel_config_limits.max_dust_limit_satoshis { - return Err(ChannelError::Close("dust limit satoshis is greater than the user specified limit")); + return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.max_dust_limit_satoshis))); } // Convert things into internal flags and prep our state: @@ -622,7 +652,7 @@ impl Channel { let their_announce = if (msg.channel_flags & 1) == 1 { true } else { false }; if config.peer_channel_config_limits.force_announced_channel_preference { if local_config.announced_channel != their_announce { - return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours")); + return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned())); } } // we either accept their preference or the preferences match @@ -633,26 +663,27 @@ impl Channel { let our_dust_limit_satoshis = Channel::::derive_our_dust_limit_satoshis(background_feerate); let remote_channel_reserve_satoshis = Channel::::get_remote_channel_reserve_satoshis(msg.funding_satoshis); if remote_channel_reserve_satoshis < our_dust_limit_satoshis { - return Err(ChannelError::Close("Suitable channel reserve not found. aborting")); + return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). our_dust_limit_satoshis is ({}).", remote_channel_reserve_satoshis, our_dust_limit_satoshis))); } if msg.channel_reserve_satoshis < our_dust_limit_satoshis { - return Err(ChannelError::Close("channel_reserve_satoshis too small")); + return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, our_dust_limit_satoshis))); } if remote_channel_reserve_satoshis < msg.dust_limit_satoshis { - return Err(ChannelError::Close("Dust limit too high for the channel reserve we require the remote to keep")); + return Err(ChannelError::Close(format!("Dust limit ({}) too high for the channel reserve we require the remote to keep ({})", msg.dust_limit_satoshis, remote_channel_reserve_satoshis))); } // 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 Err(ChannelError::Close("Insufficient funding amount for initial commitment")); + let lower_limit = background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT; + if funders_amount_msat < lower_limit { + return Err(ChannelError::Close(format!("Insufficient funding amount ({}) for initial commitment. Must be at least {}", funders_amount_msat, lower_limit))); } let to_local_msat = msg.push_msat; - let to_remote_msat = funders_amount_msat - background_feerate * COMMITMENT_TX_BASE_WEIGHT; + let to_remote_msat = funders_amount_msat - background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT; if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= remote_channel_reserve_satoshis * 1000 { - return Err(ChannelError::Close("Insufficient funding amount for initial commitment")); + return Err(ChannelError::Close("Insufficient funding amount for initial commitment".to_owned())); } let their_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() { @@ -666,12 +697,12 @@ impl Channel { None // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel } else { - return Err(ChannelError::Close("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format")); + return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format. script: ({})", script.to_bytes().to_hex()))); } }, // 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 &OptionalField::Absent => { - return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out")); + 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 }; @@ -725,7 +756,7 @@ impl Channel { last_block_connected: Default::default(), funding_tx_confirmations: 0, - feerate_per_kw: msg.feerate_per_kw as u64, + feerate_per_kw: msg.feerate_per_kw, channel_value_satoshis: msg.funding_satoshis, their_dust_limit_satoshis: msg.dust_limit_satoshis, our_dust_limit_satoshis: our_dust_limit_satoshis, @@ -755,26 +786,18 @@ impl Channel { Ok(chan) } - // Utilities to derive keys: - - fn build_local_commitment_secret(&self, idx: u64) -> SecretKey { - let res = chan_utils::build_commitment_secret(self.local_keys.commitment_seed(), idx); - SecretKey::from_slice(&res).unwrap() - } - // Utilities to build transactions: fn get_commitment_transaction_number_obscure_factor(&self) -> u64 { let mut sha = Sha256::engine(); - let our_payment_point = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.payment_key()); let their_payment_point = &self.their_pubkeys.as_ref().unwrap().payment_point.serialize(); if self.channel_outbound { - sha.input(&our_payment_point.serialize()); + sha.input(&self.local_keys.pubkeys().payment_point.serialize()); sha.input(their_payment_point); } else { sha.input(their_payment_point); - sha.input(&our_payment_point.serialize()); + sha.input(&self.local_keys.pubkeys().payment_point.serialize()); } let res = Sha256::from_engine(sha).into_inner(); @@ -804,7 +827,7 @@ impl Channel { /// Note that below-dust HTLCs are included in the third return value, but not the second, and /// sources are provided only for outbound HTLCs in the third return value. #[inline] - fn build_commitment_transaction(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, feerate_per_kw: u64, logger: &L) -> (Transaction, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) where L::Target: Logger { + fn build_commitment_transaction(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, feerate_per_kw: u32, logger: &L) -> (Transaction, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) where L::Target: Logger { let obscured_commitment_transaction_number = self.get_commitment_transaction_number_obscure_factor() ^ (INITIAL_COMMITMENT_NUMBER - commitment_number); let txins = { @@ -844,7 +867,7 @@ impl Channel { ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => { if $outbound == local { // "offered HTLC output" let htlc_in_tx = get_htlc_in_commitment!($htlc, true); - if $htlc.amount_msat / 1000 >= dust_limit_satoshis + (feerate_per_kw * HTLC_TIMEOUT_TX_WEIGHT / 1000) { + if $htlc.amount_msat / 1000 >= dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) { log_trace!(logger, " ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat); txouts.push((TxOut { script_pubkey: chan_utils::get_htlc_redeemscript(&htlc_in_tx, &keys).to_v0_p2wsh(), @@ -856,7 +879,7 @@ impl Channel { } } else { let htlc_in_tx = get_htlc_in_commitment!($htlc, false); - if $htlc.amount_msat / 1000 >= dust_limit_satoshis + (feerate_per_kw * HTLC_SUCCESS_TX_WEIGHT / 1000) { + if $htlc.amount_msat / 1000 >= dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) { log_trace!(logger, " ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat); txouts.push((TxOut { // "received HTLC output" script_pubkey: chan_utils::get_htlc_redeemscript(&htlc_in_tx, &keys).to_v0_p2wsh(), @@ -949,7 +972,7 @@ impl Channel { max_commitment_tx_output.1 = cmp::max(max_commitment_tx_output.1, value_to_remote_msat as u64); } - let total_fee: u64 = feerate_per_kw * (COMMITMENT_TX_BASE_WEIGHT + (txouts.len() as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000; + let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (txouts.len() as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000; let (value_to_self, value_to_remote) = if self.channel_outbound { (value_to_self_msat / 1000 - total_fee as i64, value_to_remote_msat / 1000) } else { @@ -1094,12 +1117,12 @@ impl Channel { /// The result is a transaction which we can revoke ownership of (ie a "local" transaction) /// TODO Some magic rust shit to compile-time check this? fn build_local_transaction_keys(&self, commitment_number: u64) -> Result { - let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(commitment_number)); - let delayed_payment_base = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.delayed_payment_base_key()); - let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key()); + let per_commitment_point = self.local_keys.get_per_commitment_point(commitment_number, &self.secp_ctx); + let delayed_payment_base = &self.local_keys.pubkeys().delayed_payment_basepoint; + let htlc_basepoint = &self.local_keys.pubkeys().htlc_basepoint; let their_pubkeys = self.their_pubkeys.as_ref().unwrap(); - Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &their_pubkeys.revocation_basepoint, &their_pubkeys.htlc_basepoint), "Local tx keys generation got bogus keys")) + Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &their_pubkeys.revocation_basepoint, &their_pubkeys.htlc_basepoint), "Local tx keys generation got bogus keys".to_owned())) } #[inline] @@ -1109,25 +1132,24 @@ impl Channel { fn build_remote_transaction_keys(&self) -> Result { //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we //may see payments to it! - let revocation_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.revocation_base_key()); - let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key()); + let revocation_basepoint = &self.local_keys.pubkeys().revocation_basepoint; + let htlc_basepoint = &self.local_keys.pubkeys().htlc_basepoint; let their_pubkeys = self.their_pubkeys.as_ref().unwrap(); - Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &their_pubkeys.delayed_payment_basepoint, &their_pubkeys.htlc_basepoint, &revocation_basepoint, &htlc_basepoint), "Remote tx keys generation got bogus keys")) + Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &their_pubkeys.delayed_payment_basepoint, &their_pubkeys.htlc_basepoint, revocation_basepoint, htlc_basepoint), "Remote tx keys generation got bogus keys".to_owned())) } /// Gets the redeemscript for the funding transaction output (ie the funding transaction output /// pays to get_funding_redeemscript().to_v0_p2wsh()). /// Panics if called before accept_channel/new_from_req pub fn get_funding_redeemscript(&self) -> Script { - let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()); - make_funding_redeemscript(&our_funding_key, self.their_funding_pubkey()) + make_funding_redeemscript(&self.local_keys.pubkeys().funding_pubkey, self.their_funding_pubkey()) } /// Builds the htlc-success or htlc-timeout transaction which spends a given HTLC output /// @local is used only to convert relevant internal structures which refer to remote vs local /// to decide value of outputs and direction of HTLCs. - fn build_htlc_transaction(&self, prev_hash: &Txid, htlc: &HTLCOutputInCommitment, local: bool, keys: &TxCreationKeys, feerate_per_kw: u64) -> Transaction { + fn build_htlc_transaction(&self, prev_hash: &Txid, htlc: &HTLCOutputInCommitment, local: bool, keys: &TxCreationKeys, feerate_per_kw: u32) -> Transaction { chan_utils::build_htlc_transaction(prev_hash, feerate_per_kw, if local { self.their_to_self_delay } else { self.our_to_self_delay }, htlc, &keys.a_delayed_payment_key, &keys.revocation_key) } @@ -1177,7 +1199,7 @@ impl Channel { } } if pending_idx == std::usize::MAX { - return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); + return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned())); } // Now update local state: @@ -1287,14 +1309,14 @@ impl Channel { }, _ => { debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to"); - return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); + return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id))); } } pending_idx = idx; } } if pending_idx == std::usize::MAX { - return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); + return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned())); } // Now update local state: @@ -1304,13 +1326,13 @@ impl Channel { &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => { if htlc_id_arg == htlc_id { debug_assert!(false, "Tried to fail an HTLC that was already fulfilled"); - return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); + return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned())); } }, &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => { if htlc_id_arg == htlc_id { debug_assert!(false, "Tried to fail an HTLC that was already failed"); - return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID")); + return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned())); } }, _ => {} @@ -1340,60 +1362,63 @@ impl Channel { pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: InitFeatures) -> Result<(), ChannelError> { // Check sanity of message fields: if !self.channel_outbound { - return Err(ChannelError::Close("Got an accept_channel message from an inbound peer")); + return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned())); } if self.channel_state != ChannelState::OurInitSent as u32 { - return Err(ChannelError::Close("Got an accept_channel message at a strange time")); + return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned())); } if msg.dust_limit_satoshis > 21000000 * 100000000 { - return Err(ChannelError::Close("Peer never wants payout outputs?")); + return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis))); } if msg.channel_reserve_satoshis > self.channel_value_satoshis { - return Err(ChannelError::Close("Bogus channel_reserve_satoshis")); + return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis))); } if msg.dust_limit_satoshis > msg.channel_reserve_satoshis { - return Err(ChannelError::Close("Bogus channel_reserve and dust_limit")); + return Err(ChannelError::Close(format!("Bogus channel_reserve ({}) and dust_limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis))); } if msg.channel_reserve_satoshis < self.our_dust_limit_satoshis { - return Err(ChannelError::Close("Peer never wants payout outputs?")); + return Err(ChannelError::Close(format!("Peer never wants payout outputs? channel_reserve_satoshis was ({}). our_dust_limit is ({})", msg.channel_reserve_satoshis, self.our_dust_limit_satoshis))); } - if msg.dust_limit_satoshis > Channel::::get_remote_channel_reserve_satoshis(self.channel_value_satoshis) { - return Err(ChannelError::Close("Dust limit is bigger than our channel reverse")); + let remote_reserve = Channel::::get_remote_channel_reserve_satoshis(self.channel_value_satoshis); + if msg.dust_limit_satoshis > remote_reserve { + return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, remote_reserve))); } - if msg.htlc_minimum_msat >= (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000 { - return Err(ChannelError::Close("Minimum htlc value is full channel value")); + let full_channel_value_msat = (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000; + if msg.htlc_minimum_msat >= full_channel_value_msat { + return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat))); } - if msg.to_self_delay > config.peer_channel_config_limits.their_to_self_delay || msg.to_self_delay > MAX_LOCAL_BREAKDOWN_TIMEOUT { - return Err(ChannelError::Close("They wanted our payments to be delayed by a needlessly long period")); + let max_delay_acceptable = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT); + if msg.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.to_self_delay))); } if msg.max_accepted_htlcs < 1 { - return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel")); + return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned())); } if msg.max_accepted_htlcs > 483 { - return Err(ChannelError::Close("max_accepted_htlcs > 483")); + return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than 483", msg.max_accepted_htlcs))); } // Now check against optional parameters as set by config... if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat { - return Err(ChannelError::Close("htlc minimum msat is higher than the user specified limit")); + return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, config.peer_channel_config_limits.max_htlc_minimum_msat))); } if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat { - return Err(ChannelError::Close("max htlc value in flight msat is less than the user specified limit")); + return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat))); } if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis { - return Err(ChannelError::Close("channel reserve satoshis is higher than the user specified limit")); + return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, config.peer_channel_config_limits.max_channel_reserve_satoshis))); } if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs { - return Err(ChannelError::Close("max accepted htlcs is less than the user specified limit")); + return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.peer_channel_config_limits.min_max_accepted_htlcs))); } if msg.dust_limit_satoshis < config.peer_channel_config_limits.min_dust_limit_satoshis { - return Err(ChannelError::Close("dust limit satoshis is less than the user specified limit")); + return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.min_dust_limit_satoshis))); } if msg.dust_limit_satoshis > config.peer_channel_config_limits.max_dust_limit_satoshis { - return Err(ChannelError::Close("dust limit satoshis is greater than the user specified limit")); + return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.max_dust_limit_satoshis))); } if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth { - return Err(ChannelError::Close("We consider the minimum depth to be unreasonably large")); + return Err(ChannelError::Close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", config.peer_channel_config_limits.max_minimum_depth, msg.minimum_depth))); } let their_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() { @@ -1407,12 +1432,12 @@ impl Channel { None // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel } else { - return Err(ChannelError::Close("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format")); + return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format. scriptpubkey: ({})", script.to_bytes().to_hex()))); } }, // 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 &OptionalField::Absent => { - return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out")); + 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 }; @@ -1433,7 +1458,7 @@ impl Channel { htlc_basepoint: msg.htlc_basepoint }; - self.local_keys.set_remote_channel_pubkeys(&their_pubkeys); + self.local_keys.on_accept(&their_pubkeys, msg.to_self_delay, self.our_to_self_delay); self.their_pubkeys = Some(their_pubkeys); self.their_cur_commitment_point = Some(msg.first_per_commitment_point); @@ -1453,14 +1478,14 @@ impl Channel { // They sign the "local" commitment transaction... log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.their_funding_pubkey().serialize()), encode::serialize_hex(&local_initial_commitment_tx), log_bytes!(local_sighash[..]), encode::serialize_hex(&funding_script)); - secp_check!(self.secp_ctx.verify(&local_sighash, &sig, self.their_funding_pubkey()), "Invalid funding_created signature from peer"); + secp_check!(self.secp_ctx.verify(&local_sighash, &sig, self.their_funding_pubkey()), "Invalid funding_created signature from peer".to_owned()); - let localtx = LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx, sig.clone(), &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), self.their_funding_pubkey(), local_keys, self.feerate_per_kw, Vec::new()); + let localtx = LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx, sig.clone(), &self.local_keys.pubkeys().funding_pubkey, self.their_funding_pubkey(), local_keys, self.feerate_per_kw, Vec::new()); let remote_keys = self.build_remote_transaction_keys()?; let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw, logger).0; - let remote_signature = self.local_keys.sign_remote_commitment(self.feerate_per_kw, &remote_initial_commitment_tx, &remote_keys, &Vec::new(), self.our_to_self_delay, &self.secp_ctx) - .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed"))?.0; + let remote_signature = self.local_keys.sign_remote_commitment(self.feerate_per_kw, &remote_initial_commitment_tx, &remote_keys, &Vec::new(), &self.secp_ctx) + .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0; // We sign the "remote" commitment transaction, allowing them to broadcast the tx if they wish. Ok((remote_initial_commitment_tx, localtx, remote_signature)) @@ -1472,13 +1497,13 @@ impl Channel { pub fn funding_created(&mut self, msg: &msgs::FundingCreated, logger: &L) -> Result<(msgs::FundingSigned, ChannelMonitor), ChannelError> where L::Target: Logger { if self.channel_outbound { - return Err(ChannelError::Close("Received funding_created for an outbound channel?")); + return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned())); } if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) { // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT // remember the channel, so it's safe to just send an error_message here and drop the // channel. - return Err(ChannelError::Close("Received funding_created after we got the channel!")); + return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned())); } if self.commitment_secrets.get_min_seen_secret() != (1 << 48) || self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER || @@ -1535,10 +1560,10 @@ impl Channel { /// If this call is successful, broadcast the funding transaction (and not before!) pub fn funding_signed(&mut self, msg: &msgs::FundingSigned, logger: &L) -> Result, ChannelError> where L::Target: Logger { if !self.channel_outbound { - return Err(ChannelError::Close("Received funding_signed for an inbound channel?")); + return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned())); } if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 { - return Err(ChannelError::Close("Received funding_signed in strange state!")); + return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned())); } if self.commitment_secrets.get_min_seen_secret() != (1 << 48) || self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER || @@ -1559,7 +1584,7 @@ impl Channel { // They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish. if let Err(_) = self.secp_ctx.verify(&local_sighash, &msg.signature, their_funding_pubkey) { - return Err(ChannelError::Close("Invalid funding_signed signature from peer")); + return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned())); } let their_pubkeys = self.their_pubkeys.as_ref().unwrap(); @@ -1568,7 +1593,7 @@ impl Channel { let funding_txo_script = funding_redeemscript.to_v0_p2wsh(); macro_rules! create_monitor { () => { { - let local_commitment_tx = LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx.clone(), msg.signature.clone(), &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), their_funding_pubkey, local_keys.clone(), self.feerate_per_kw, Vec::new()); + let local_commitment_tx = LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx.clone(), msg.signature.clone(), &self.local_keys.pubkeys().funding_pubkey, their_funding_pubkey, local_keys.clone(), self.feerate_per_kw, Vec::new()); let mut channel_monitor = ChannelMonitor::new(self.local_keys.clone(), &self.shutdown_pubkey, self.our_to_self_delay, &self.destination_script, (funding_txo.clone(), funding_txo_script.clone()), @@ -1596,7 +1621,7 @@ impl Channel { pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError> { if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent funding_locked when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent funding_locked when we needed a channel_reestablish".to_owned())); } let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS); @@ -1614,12 +1639,12 @@ impl Channel { (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32)) { if self.their_cur_commitment_point != Some(msg.next_per_commitment_point) { - return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point")); + return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point".to_owned())); } // They probably disconnected/reconnected and re-sent the funding_locked, which is required return Ok(()); } else { - return Err(ChannelError::Close("Peer sent a funding_locked at a strange time")); + return Err(ChannelError::Close("Peer sent a funding_locked at a strange time".to_owned())); } self.their_prev_commitment_point = self.their_cur_commitment_point; @@ -1665,30 +1690,105 @@ impl Channel { cmp::min(self.value_to_self_msat as i64 - self.get_outbound_pending_htlc_stats().1 as i64, 0) as u64) } - pub fn update_add_htlc(&mut self, msg: &msgs::UpdateAddHTLC, pending_forward_state: PendingHTLCStatus) -> Result<(), ChannelError> { - if (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32) { - return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state")); + // Get the fee cost of a commitment tx with a given number of HTLC outputs. + // Note that num_htlcs should not include dust HTLCs. + fn commit_tx_fee_msat(&self, num_htlcs: usize) -> u64 { + // Note that we need to divide before multiplying to round properly, + // since the lowest denomination of bitcoin on-chain is the satoshi. + (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * self.feerate_per_kw as u64 / 1000 * 1000 + } + + // Get the commitment tx fee for the local (i.e our) next commitment transaction + // based on the number of pending HTLCs that are on track to be in our next + // commitment tx. `addl_htcs` is an optional parameter allowing the caller + // to add a number of additional HTLCs to the calculation. Note that dust + // HTLCs are excluded. + fn next_local_commit_tx_fee_msat(&self, addl_htlcs: usize) -> u64 { + assert!(self.channel_outbound); + + let mut their_acked_htlcs = self.pending_inbound_htlcs.len(); + for ref htlc in self.pending_outbound_htlcs.iter() { + if htlc.amount_msat / 1000 <= self.our_dust_limit_satoshis { + continue + } + match htlc.state { + OutboundHTLCState::Committed => their_acked_htlcs += 1, + OutboundHTLCState::RemoteRemoved {..} => their_acked_htlcs += 1, + OutboundHTLCState::LocalAnnounced {..} => their_acked_htlcs += 1, + _ => {}, + } + } + + for htlc in self.holding_cell_htlc_updates.iter() { + match htlc { + &HTLCUpdateAwaitingACK::AddHTLC { .. } => their_acked_htlcs += 1, + _ => {}, + } + } + + self.commit_tx_fee_msat(their_acked_htlcs + addl_htlcs) + } + + // Get the commitment tx fee for the remote's next commitment transaction + // based on the number of pending HTLCs that are on track to be in their + // next commitment tx. `addl_htcs` is an optional parameter allowing the caller + // to add a number of additional HTLCs to the calculation. Note that dust HTLCs + // are excluded. + fn next_remote_commit_tx_fee_msat(&self, addl_htlcs: usize) -> u64 { + assert!(!self.channel_outbound); + + // When calculating the set of HTLCs which will be included in their next + // commitment_signed, all inbound HTLCs are included (as all states imply it will be + // included) and only committed outbound HTLCs, see below. + let mut their_acked_htlcs = self.pending_inbound_htlcs.len(); + for ref htlc in self.pending_outbound_htlcs.iter() { + if htlc.amount_msat / 1000 <= self.their_dust_limit_satoshis { + continue + } + // We only include outbound HTLCs if it will not be included in their next + // commitment_signed, i.e. if they've responded to us with an RAA after announcement. + match htlc.state { + OutboundHTLCState::Committed => their_acked_htlcs += 1, + OutboundHTLCState::RemoteRemoved {..} => their_acked_htlcs += 1, + _ => {}, + } + } + + self.commit_tx_fee_msat(their_acked_htlcs + addl_htlcs) + } + + pub fn update_add_htlc(&mut self, msg: &msgs::UpdateAddHTLC, mut pending_forward_status: PendingHTLCStatus, create_pending_htlc_status: F, logger: &L) -> Result<(), ChannelError> + where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger { + // We can't accept HTLCs sent after we've sent a shutdown. + let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32); + if local_sent_shutdown { + pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|20); + } + // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec. + let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32); + if remote_sent_shutdown { + return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned())); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned())); } if msg.amount_msat > self.channel_value_satoshis * 1000 { - return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel")); + return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel".to_owned())); } if msg.amount_msat == 0 { - return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC")); + return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC".to_owned())); } if msg.amount_msat < self.our_htlc_minimum_msat { - return Err(ChannelError::Close("Remote side tried to send less than our minimum HTLC value")); + return Err(ChannelError::Close(format!("Remote side tried to send less than our minimum HTLC value. Lower limit: ({}). Actual: ({})", self.our_htlc_minimum_msat, msg.amount_msat))); } let (inbound_htlc_count, htlc_inbound_value_msat) = self.get_inbound_pending_htlc_stats(); if inbound_htlc_count + 1 > OUR_MAX_HTLCS as u32 { - return Err(ChannelError::Close("Remote tried to push more than our max accepted HTLCs")); + return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", OUR_MAX_HTLCS))); } - // Check our_max_htlc_value_in_flight_msat - if htlc_inbound_value_msat + msg.amount_msat > Channel::::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis) { - return Err(ChannelError::Close("Remote HTLC add would put them over our max HTLC value")); + let our_max_htlc_value_in_flight_msat = Channel::::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis); + if htlc_inbound_value_msat + msg.amount_msat > our_max_htlc_value_in_flight_msat { + return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", our_max_htlc_value_in_flight_msat))); } // Check remote_channel_reserve_satoshis (we're getting paid, so they have to at least meet // the reserve_satoshis we told them to always have as direct payment so that they lose @@ -1710,18 +1810,65 @@ impl Channel { removed_outbound_total_msat += htlc.amount_msat; } } - if htlc_inbound_value_msat + msg.amount_msat + self.value_to_self_msat > (self.channel_value_satoshis - Channel::::get_remote_channel_reserve_satoshis(self.channel_value_satoshis)) * 1000 + removed_outbound_total_msat { - return Err(ChannelError::Close("Remote HTLC add would put them under their reserve value")); + + let pending_value_to_self_msat = + self.value_to_self_msat + htlc_inbound_value_msat - removed_outbound_total_msat; + let pending_remote_value_msat = + self.channel_value_satoshis * 1000 - pending_value_to_self_msat; + if pending_remote_value_msat < msg.amount_msat { + return Err(ChannelError::Close("Remote HTLC add would overdraw remaining funds".to_owned())); } + + // Check that the remote can afford to pay for this HTLC on-chain at the current + // feerate_per_kw, while maintaining their channel reserve (as required by the spec). + let remote_commit_tx_fee_msat = if self.channel_outbound { 0 } else { + // +1 for this HTLC. + self.next_remote_commit_tx_fee_msat(1) + }; + if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat { + return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned())); + }; + + let chan_reserve_msat = + Channel::::get_remote_channel_reserve_satoshis(self.channel_value_satoshis) * 1000; + if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < chan_reserve_msat { + return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned())); + } + + if !self.channel_outbound { + // `+1` for this HTLC, `2 *` and `+1` fee spike buffer we keep for the remote. This deviates from the + // spec because in the spec, the fee spike buffer requirement doesn't exist on the receiver's side, + // only on the sender's. + // Note that when we eventually remove support for fee updates and switch to anchor output fees, + // we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep the extra +1 + // as we should still be able to afford adding this HTLC plus one more future HTLC, regardless of + // being sensitive to fee spikes. + let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(1 + 1); + if pending_remote_value_msat - msg.amount_msat - chan_reserve_msat < remote_fee_cost_incl_stuck_buffer_msat { + // Note that if the pending_forward_status is not updated here, then it's because we're already failing + // the HTLC, i.e. its status is already set to failing. + log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation"); + pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7); + } + } else { + // Check that they won't violate our local required channel reserve by adding this HTLC. + + // +1 for this HTLC. + let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(1); + if self.value_to_self_msat < self.local_channel_reserve_satoshis * 1000 + local_commit_tx_fee_msat { + return Err(ChannelError::Close("Cannot receive value that would put us under local channel reserve value".to_owned())); + } + } + if self.next_remote_htlc_id != msg.htlc_id { - return Err(ChannelError::Close("Remote skipped HTLC ID")); + return Err(ChannelError::Close(format!("Remote skipped HTLC ID (skipped ID: {})", self.next_remote_htlc_id))); } if msg.cltv_expiry >= 500000000 { - return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height")); + return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned())); } if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 { - if let PendingHTLCStatus::Forward(_) = pending_forward_state { + if let PendingHTLCStatus::Forward(_) = pending_forward_status { panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing"); } } @@ -1733,7 +1880,7 @@ impl Channel { amount_msat: msg.amount_msat, payment_hash: msg.payment_hash, cltv_expiry: msg.cltv_expiry, - state: InboundHTLCState::RemoteAnnounced(pending_forward_state), + state: InboundHTLCState::RemoteAnnounced(pending_forward_status), }); Ok(()) } @@ -1747,30 +1894,30 @@ impl Channel { None => {}, Some(payment_hash) => if payment_hash != htlc.payment_hash { - return Err(ChannelError::Close("Remote tried to fulfill HTLC with an incorrect preimage")); + return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id))); } }; match htlc.state { OutboundHTLCState::LocalAnnounced(_) => - return Err(ChannelError::Close("Remote tried to fulfill/fail HTLC before it had been committed")), + return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) before it had been committed", htlc_id))), OutboundHTLCState::Committed => { htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason); }, OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) => - return Err(ChannelError::Close("Remote tried to fulfill/fail HTLC that they'd already fulfilled/failed")), + return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) that they'd already fulfilled/failed", htlc_id))), } return Ok(&htlc.source); } } - Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find")) + Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned())) } pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { - return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state")); + return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned())); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned())); } let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner()); @@ -1779,10 +1926,10 @@ impl Channel { pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { - return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state")); + return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned())); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned())); } self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?; @@ -1791,10 +1938,10 @@ impl Channel { pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { - return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state")); + return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned())); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish".to_owned())); } self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?; @@ -1806,13 +1953,13 @@ impl Channel { L::Target: Logger { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { - return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state"))); + return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned()))); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish"))); + return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned()))); } if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() { - return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds"))); + return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned()))); } let funding_script = self.get_funding_redeemscript(); @@ -1836,22 +1983,22 @@ impl Channel { let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_commitment_tx.0).sighash_all(&local_commitment_tx.0.input[0], &funding_script, self.channel_value_satoshis)[..]); log_trace!(logger, "Checking commitment tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(msg.signature.serialize_compact()[..]), log_bytes!(self.their_funding_pubkey().serialize()), encode::serialize_hex(&local_commitment_tx.0), log_bytes!(local_sighash[..]), encode::serialize_hex(&funding_script)); if let Err(_) = self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey()) { - return Err((None, ChannelError::Close("Invalid commitment tx signature from peer"))); + return Err((None, ChannelError::Close("Invalid commitment tx signature from peer".to_owned()))); } //If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction if update_fee { let num_htlcs = local_commitment_tx.1; - let total_fee: u64 = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000; + let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000; let remote_reserve_we_require = Channel::::get_remote_channel_reserve_satoshis(self.channel_value_satoshis); if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + remote_reserve_we_require { - return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee"))); + return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned()))); } } if msg.htlc_signatures.len() != local_commitment_tx.1 { - return Err((None, ChannelError::Close("Got wrong number of HTLC signatures from remote"))); + return Err((None, ChannelError::Close(format!("Got wrong number of HTLC signatures ({}) from remote. It must be {}", msg.htlc_signatures.len(), local_commitment_tx.1)))); } // TODO: Merge these two, sadly they are currently both required to be passed separately to @@ -1865,7 +2012,7 @@ impl Channel { let htlc_sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]); log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(local_keys.b_htlc_key.serialize()), encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript)); if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &local_keys.b_htlc_key) { - return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer"))); + return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer".to_owned()))); } htlcs_without_source.push((htlc.clone(), Some(msg.htlc_signatures[idx]))); htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source)); @@ -1875,8 +2022,8 @@ impl Channel { } } - let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number - 1)); - let per_commitment_secret = chan_utils::build_commitment_secret(self.local_keys.commitment_seed(), self.cur_local_commitment_transaction_number + 1); + let next_per_commitment_point = self.local_keys.get_per_commitment_point(self.cur_local_commitment_transaction_number - 1, &self.secp_ctx); + let per_commitment_secret = self.local_keys.release_commitment_secret(self.cur_local_commitment_transaction_number + 1); // Update state now that we've passed all the can-fail calls... let mut need_our_commitment = false; @@ -1899,7 +2046,7 @@ impl Channel { let mut monitor_update = ChannelMonitorUpdate { update_id: self.latest_monitor_update_id, updates: vec![ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { - commitment_tx: LocalCommitmentTransaction::new_missing_local_sig(local_commitment_tx.0, msg.signature.clone(), &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), &their_funding_pubkey, local_keys, self.feerate_per_kw, htlcs_without_source), + commitment_tx: LocalCommitmentTransaction::new_missing_local_sig(local_commitment_tx.0, msg.signature.clone(), &self.local_keys.pubkeys().funding_pubkey, &their_funding_pubkey, local_keys, self.feerate_per_kw, htlcs_without_source), htlc_outputs: htlcs_and_sigs }] }; @@ -1945,7 +2092,7 @@ impl Channel { } // TODO: Call maybe_propose_first_closing_signed on restoration (or call it here and // re-send the message on restoration) - return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA"))); + return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA".to_owned()))); } let (our_commitment_signed, closing_signed) = if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 { @@ -1971,7 +2118,7 @@ impl Channel { /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them /// fulfilling or failing the last pending HTLC) - fn free_holding_cell_htlcs(&mut self, logger: &L) -> Result, ChannelError> where L::Target: Logger { + fn free_holding_cell_htlcs(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger { assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0); if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() { log_trace!(logger, "Freeing holding cell with {} HTLC updates{}", self.holding_cell_htlc_updates.len(), if self.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }); @@ -1986,110 +2133,94 @@ impl Channel { let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len()); let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len()); let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len()); - let mut err = None; + let mut htlcs_to_fail = Vec::new(); for htlc_update in htlc_updates.drain(..) { // Note that this *can* fail, though it should be due to rather-rare conditions on // fee races with adding too many outputs which push our total payments just over // the limit. In case it's less rare than I anticipate, we may want to revisit // handling this case better and maybe fulfilling some of the HTLCs while attempting // to rebalance channels. - if err.is_some() { // We're back to AwaitingRemoteRevoke (or are about to fail the channel) - self.holding_cell_htlc_updates.push(htlc_update); - } else { - match &htlc_update { - &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => { - match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) { - Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()), - Err(e) => { - match e { - ChannelError::Ignore(ref msg) => { - log_info!(logger, "Failed to send HTLC with payment_hash {} due to {}", log_bytes!(payment_hash.0), msg); - }, - _ => { - log_info!(logger, "Failed to send HTLC with payment_hash {} resulting in a channel closure during holding_cell freeing", log_bytes!(payment_hash.0)); - }, - } - err = Some(e); + match &htlc_update { + &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => { + match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) { + Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()), + Err(e) => { + match e { + ChannelError::Ignore(ref msg) => { + log_info!(logger, "Failed to send HTLC with payment_hash {} due to {}", log_bytes!(payment_hash.0), msg); + // If we fail to send here, then this HTLC should + // be failed backwards. Failing to send here + // indicates that this HTLC may keep being put back + // into the holding cell without ever being + // successfully forwarded/failed/fulfilled, causing + // our counterparty to eventually close on us. + htlcs_to_fail.push((source.clone(), *payment_hash)); + }, + _ => { + panic!("Got a non-IgnoreError action trying to send holding cell HTLC"); + }, } } - }, - &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => { - match self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) { - Ok((update_fulfill_msg_option, additional_monitor_update_opt)) => { - update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap()); - if let Some(mut additional_monitor_update) = additional_monitor_update_opt { - monitor_update.updates.append(&mut additional_monitor_update.updates); - } - }, - Err(e) => { - if let ChannelError::Ignore(_) = e {} - else { - panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC"); - } + } + }, + &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => { + match self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) { + Ok((update_fulfill_msg_option, additional_monitor_update_opt)) => { + update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap()); + if let Some(mut additional_monitor_update) = additional_monitor_update_opt { + monitor_update.updates.append(&mut additional_monitor_update.updates); + } + }, + Err(e) => { + if let ChannelError::Ignore(_) = e {} + else { + panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC"); } } - }, - &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => { - match self.get_update_fail_htlc(htlc_id, err_packet.clone()) { - Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()), - Err(e) => { - if let ChannelError::Ignore(_) = e {} - else { - panic!("Got a non-IgnoreError action trying to fail holding cell HTLC"); - } + } + }, + &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => { + match self.get_update_fail_htlc(htlc_id, err_packet.clone()) { + Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()), + Err(e) => { + if let ChannelError::Ignore(_) = e {} + else { + panic!("Got a non-IgnoreError action trying to fail holding cell HTLC"); } } - }, - } - if err.is_some() { - self.holding_cell_htlc_updates.push(htlc_update); - if let Some(ChannelError::Ignore(_)) = err { - // If we failed to add the HTLC, but got an Ignore error, we should - // still send the new commitment_signed, so reset the err to None. - err = None; } - } + }, } } - //TODO: Need to examine the type of err - if it's a fee issue or similar we may want to - //fail it back the route, if it's a temporary issue we can ignore it... - match err { - None => { - if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() { - // This should never actually happen and indicates we got some Errs back - // from update_fulfill_htlc/update_fail_htlc, but we handle it anyway in - // case there is some strange way to hit duplicate HTLC removes. - return Ok(None); - } - let update_fee = if let Some(feerate) = self.holding_cell_update_fee { - self.pending_update_fee = self.holding_cell_update_fee.take(); - Some(msgs::UpdateFee { - channel_id: self.channel_id, - feerate_per_kw: feerate as u32, - }) - } else { - None - }; + if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() { + return Ok((None, htlcs_to_fail)); + } + let update_fee = if let Some(feerate) = self.holding_cell_update_fee { + self.pending_update_fee = self.holding_cell_update_fee.take(); + Some(msgs::UpdateFee { + channel_id: self.channel_id, + feerate_per_kw: feerate as u32, + }) + } else { + None + }; - let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?; - // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id - // but we want them to be strictly increasing by one, so reset it here. - self.latest_monitor_update_id = monitor_update.update_id; - monitor_update.updates.append(&mut additional_update.updates); + let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?; + // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id + // but we want them to be strictly increasing by one, so reset it here. + self.latest_monitor_update_id = monitor_update.update_id; + monitor_update.updates.append(&mut additional_update.updates); - Ok(Some((msgs::CommitmentUpdate { - update_add_htlcs, - update_fulfill_htlcs, - update_fail_htlcs, - update_fail_malformed_htlcs: Vec::new(), - update_fee: update_fee, - commitment_signed, - }, monitor_update))) - }, - Some(e) => Err(e) - } + Ok((Some((msgs::CommitmentUpdate { + update_add_htlcs, + update_fulfill_htlcs, + update_fail_htlcs, + update_fail_malformed_htlcs: Vec::new(), + update_fee: update_fee, + commitment_signed, + }, monitor_update)), htlcs_to_fail)) } else { - Ok(None) + Ok((None, Vec::new())) } } @@ -2098,23 +2229,23 @@ impl Channel { /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail, /// generating an appropriate error *after* the channel state has been updated based on the /// revoke_and_ack message. - pub fn revoke_and_ack(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &F, logger: &L) -> Result<(Option, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option, ChannelMonitorUpdate), ChannelError> + pub fn revoke_and_ack(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &F, logger: &L) -> Result<(Option, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>), ChannelError> where F::Target: FeeEstimator, L::Target: Logger, { if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) { - return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state")); + return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned())); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned())); } if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() { - return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds")); + return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned())); } if let Some(their_prev_commitment_point) = self.their_prev_commitment_point { - if PublicKey::from_secret_key(&self.secp_ctx, &secp_check!(SecretKey::from_slice(&msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret")) != their_prev_commitment_point { - return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey")); + if PublicKey::from_secret_key(&self.secp_ctx, &secp_check!(SecretKey::from_slice(&msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret".to_owned())) != their_prev_commitment_point { + return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey".to_owned())); } } @@ -2126,11 +2257,11 @@ impl Channel { // lot of work, and there's some chance this is all a misunderstanding anyway. // We have to do *something*, though, since our signer may get mad at us for otherwise // jumping a remote commitment number, so best to just force-close and move on. - return Err(ChannelError::Close("Received an unexpected revoke_and_ack")); + return Err(ChannelError::Close("Received an unexpected revoke_and_ack".to_owned())); } self.commitment_secrets.provide_secret(self.cur_remote_commitment_transaction_number + 1, msg.per_commitment_secret) - .map_err(|_| ChannelError::Close("Previous secrets did not match new one"))?; + .map_err(|_| ChannelError::Close("Previous secrets did not match new one".to_owned()))?; self.latest_monitor_update_id += 1; let mut monitor_update = ChannelMonitorUpdate { update_id: self.latest_monitor_update_id, @@ -2273,11 +2404,11 @@ impl Channel { } self.monitor_pending_forwards.append(&mut to_forward_infos); self.monitor_pending_failures.append(&mut revoked_htlcs); - return Ok((None, Vec::new(), Vec::new(), None, monitor_update)) + return Ok((None, Vec::new(), Vec::new(), None, monitor_update, Vec::new())) } match self.free_holding_cell_htlcs(logger)? { - Some((mut commitment_update, mut additional_update)) => { + (Some((mut commitment_update, mut additional_update)), htlcs_to_fail) => { commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len()); for fail_msg in update_fail_htlcs.drain(..) { commitment_update.update_fail_htlcs.push(fail_msg); @@ -2292,9 +2423,9 @@ impl Channel { self.latest_monitor_update_id = monitor_update.update_id; monitor_update.updates.append(&mut additional_update.updates); - Ok((Some(commitment_update), to_forward_infos, revoked_htlcs, None, monitor_update)) + Ok((Some(commitment_update), to_forward_infos, revoked_htlcs, None, monitor_update, htlcs_to_fail)) }, - None => { + (None, htlcs_to_fail) => { if require_commitment { let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?; @@ -2310,9 +2441,9 @@ impl Channel { update_fail_malformed_htlcs, update_fee: None, commitment_signed - }), to_forward_infos, revoked_htlcs, None, monitor_update)) + }), to_forward_infos, revoked_htlcs, None, monitor_update, htlcs_to_fail)) } else { - Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), monitor_update)) + Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), monitor_update, htlcs_to_fail)) } } } @@ -2322,7 +2453,7 @@ impl Channel { /// Adds a pending update to this channel. See the doc for send_htlc for /// further details on the optionness of the return value. /// You MUST call send_commitment prior to any other calls on this Channel - fn send_update_fee(&mut self, feerate_per_kw: u64) -> Option { + fn send_update_fee(&mut self, feerate_per_kw: u32) -> Option { if !self.channel_outbound { panic!("Cannot send fee from inbound channel"); } @@ -2343,11 +2474,11 @@ impl Channel { Some(msgs::UpdateFee { channel_id: self.channel_id, - feerate_per_kw: feerate_per_kw as u32, + feerate_per_kw: feerate_per_kw, }) } - pub fn send_update_fee_and_commit(&mut self, feerate_per_kw: u64, logger: &L) -> Result, ChannelError> where L::Target: Logger { + pub fn send_update_fee_and_commit(&mut self, feerate_per_kw: u32, logger: &L) -> Result, ChannelError> where L::Target: Logger { match self.send_update_fee(feerate_per_kw) { Some(update_fee) => { let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?; @@ -2414,6 +2545,11 @@ impl Channel { self.holding_cell_htlc_updates.retain(|htlc_update| { match htlc_update { + // Note that currently on channel reestablish we assert that there are + // no holding cell HTLC update_adds, so if in the future we stop + // dropping added HTLCs here and failing them backwards, then there will + // need to be corresponding changes made in the Channel's re-establish + // logic. &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => { outbound_drops.push((source.clone(), payment_hash.clone())); false @@ -2461,8 +2597,7 @@ impl Channel { let funding_locked = if self.monitor_pending_funding_locked { assert!(!self.channel_outbound, "Funding transaction broadcast without FundingBroadcastSafe!"); self.monitor_pending_funding_locked = false; - let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number); - let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret); + let next_per_commitment_point = self.local_keys.get_per_commitment_point(self.cur_local_commitment_transaction_number, &self.secp_ctx); Some(msgs::FundingLocked { channel_id: self.channel_id(), next_per_commitment_point: next_per_commitment_point, @@ -2502,20 +2637,20 @@ impl Channel { where F::Target: FeeEstimator { if self.channel_outbound { - return Err(ChannelError::Close("Non-funding remote tried to update channel fee")); + return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned())); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned())); } Channel::::check_remote_fee(fee_estimator, msg.feerate_per_kw)?; - self.pending_update_fee = Some(msg.feerate_per_kw as u64); + self.pending_update_fee = Some(msg.feerate_per_kw); self.update_time_counter += 1; Ok(()) } fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK { - let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number)); - let per_commitment_secret = chan_utils::build_commitment_secret(self.local_keys.commitment_seed(), self.cur_local_commitment_transaction_number + 2); + let next_per_commitment_point = self.local_keys.get_per_commitment_point(self.cur_local_commitment_transaction_number, &self.secp_ctx); + let per_commitment_secret = self.local_keys.release_commitment_secret(self.cur_local_commitment_transaction_number + 2); msgs::RevokeAndACK { channel_id: self.channel_id, per_commitment_secret, @@ -2587,23 +2722,26 @@ impl Channel { // While BOLT 2 doesn't indicate explicitly we should error this channel here, it // almost certainly indicates we are going to end up out-of-sync in some way, so we // just close here instead of trying to recover. - return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect")); + return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect".to_owned())); } if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_local_commitment_number == 0 { - return Err(ChannelError::Close("Peer sent a garbage channel_reestablish")); + return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned())); } if msg.next_remote_commitment_number > 0 { match msg.data_loss_protect { OptionalField::Present(ref data_loss) => { - if chan_utils::build_commitment_secret(self.local_keys.commitment_seed(), INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1) != data_loss.your_last_per_commitment_secret { - return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided")); + let expected_point = self.local_keys.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx); + let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret) + .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?; + if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) { + return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned())); } if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number { return Err(ChannelError::CloseDelayBroadcast( - "We have fallen behind - we have received proof that if we broadcast remote is going to claim our funds - we can't do any automated broadcasting" + "We have fallen behind - we have received proof that if we broadcast remote is going to claim our funds - we can't do any automated broadcasting".to_owned() )); } }, @@ -2627,15 +2765,14 @@ impl Channel { if self.channel_state & (ChannelState::OurFundingLocked as u32) == 0 || self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 { if msg.next_remote_commitment_number != 0 { - return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet")); + return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned())); } // Short circuit the whole handler as there is nothing we can resend them return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg)); } // We have OurFundingLocked set! - let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number); - let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret); + let next_per_commitment_point = self.local_keys.get_per_commitment_point(self.cur_local_commitment_transaction_number, &self.secp_ctx); return Ok((Some(msgs::FundingLocked { channel_id: self.channel_id(), next_per_commitment_point: next_per_commitment_point, @@ -2654,7 +2791,7 @@ impl Channel { Some(self.get_last_revoke_and_ack()) } } else { - return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction")); + return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned())); }; // We increment cur_remote_commitment_transaction_number only upon receipt of @@ -2665,8 +2802,7 @@ impl Channel { let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number == 1 { // We should never have to worry about MonitorUpdateFailed resending FundingLocked - let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number); - let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret); + let next_per_commitment_point = self.local_keys.get_per_commitment_point(self.cur_local_commitment_transaction_number, &self.secp_ctx); Some(msgs::FundingLocked { channel_id: self.channel_id(), next_per_commitment_point: next_per_commitment_point, @@ -2681,6 +2817,14 @@ impl Channel { } if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 { + // Note that if in the future we no longer drop holding cell update_adds on peer + // disconnect, this logic will need to be updated. + for htlc_update in self.holding_cell_htlc_updates.iter() { + if let &HTLCUpdateAwaitingACK::AddHTLC { .. } = htlc_update { + debug_assert!(false, "There shouldn't be any add-HTLCs in the holding cell now because they should have been dropped on peer disconnect. Panic here because said HTLCs won't be handled correctly."); + } + } + // We're up-to-date and not waiting on a remote revoke (if we are our // channel_reestablish should result in them sending a revoke_and_ack), but we may // have received some updates while we were disconnected. Free the holding cell @@ -2688,8 +2832,18 @@ impl Channel { match self.free_holding_cell_htlcs(logger) { Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)), Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"), - Ok(Some((commitment_update, monitor_update))) => return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), shutdown_msg)), - Ok(None) => return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg)), + Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => { + // If in the future we no longer drop holding cell update_adds on peer + // disconnect, we may be handed some HTLCs to fail backwards here. + assert!(htlcs_to_fail.is_empty()); + return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), shutdown_msg)); + }, + Ok((None, htlcs_to_fail)) => { + // If in the future we no longer drop holding cell update_adds on peer + // disconnect, we may be handed some HTLCs to fail backwards here. + assert!(htlcs_to_fail.is_empty()); + return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg)); + }, } } else { return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg)); @@ -2708,7 +2862,7 @@ impl Channel { return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), shutdown_msg)); } else { - return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction")); + return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned())); } } @@ -2726,7 +2880,7 @@ impl Channel { proposed_feerate = self.feerate_per_kw; } let tx_weight = Self::get_closing_transaction_weight(&self.get_closing_scriptpubkey(), self.their_shutdown_scriptpubkey.as_ref().unwrap()); - let proposed_total_fee_satoshis = proposed_feerate * tx_weight / 1000; + let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000; let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(proposed_total_fee_satoshis, false); let our_sig = self.local_keys @@ -2746,17 +2900,17 @@ impl Channel { where F::Target: FeeEstimator { if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned())); } if self.channel_state < ChannelState::FundingSent as u32 { // Spec says we should fail the connection, not the channel, but that's nonsense, there // are plenty of reasons you may want to fail a channel pre-funding, and spec says you // can do that via error message without getting a connection fail anyway... - return Err(ChannelError::Close("Peer sent shutdown pre-funding generation")); + return Err(ChannelError::Close("Peer sent shutdown pre-funding generation".to_owned())); } for htlc in self.pending_inbound_htlcs.iter() { if let InboundHTLCState::RemoteAnnounced(_) = htlc.state { - return Err(ChannelError::Close("Got shutdown with remote pending HTLCs")); + return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned())); } } assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0); @@ -2764,17 +2918,17 @@ impl Channel { // BOLT 2 says we must only send a scriptpubkey of certain standard forms, which are up to // 34 bytes in length, so don't let the remote peer feed us some super fee-heavy script. if self.channel_outbound && msg.scriptpubkey.len() > 34 { - return Err(ChannelError::Close("Got shutdown_scriptpubkey of absurd length from remote peer")); + return Err(ChannelError::Close(format!("Got shutdown_scriptpubkey ({}) of absurd length from remote peer", msg.scriptpubkey.to_bytes().to_hex()))); } //Check shutdown_scriptpubkey form as BOLT says we must if !msg.scriptpubkey.is_p2pkh() && !msg.scriptpubkey.is_p2sh() && !msg.scriptpubkey.is_v0_p2wpkh() && !msg.scriptpubkey.is_v0_p2wsh() { - return Err(ChannelError::Close("Got a nonstandard scriptpubkey from remote peer")); + return Err(ChannelError::Close(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex()))); } if self.their_shutdown_scriptpubkey.is_some() { if Some(&msg.scriptpubkey) != self.their_shutdown_scriptpubkey.as_ref() { - return Err(ChannelError::Close("Got shutdown request with a scriptpubkey which did not match their previous scriptpubkey")); + return Err(ChannelError::Close(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_bytes().to_hex()))); } } else { self.their_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone()); @@ -2825,7 +2979,7 @@ impl Channel { tx.input[0].witness.push(Vec::new()); // First is the multisig dummy - let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()).serialize(); + let our_funding_key = self.local_keys.pubkeys().funding_pubkey.serialize(); let their_funding_key = self.their_funding_pubkey().serialize(); if our_funding_key[..] < their_funding_key[..] { tx.input[0].witness.push(our_sig.serialize_der().to_vec()); @@ -2844,22 +2998,22 @@ impl Channel { where F::Target: FeeEstimator { if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK { - return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown")); + return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned())); } if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 { - return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish")); + return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned())); } if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() { - return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs")); + return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs".to_owned())); } if msg.fee_satoshis > 21000000 * 10000000 { //this is required to stop potential overflow in build_closing_transaction - return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee")); + return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned())); } let funding_redeemscript = self.get_funding_redeemscript(); let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false); if used_total_fee != msg.fee_satoshis { - return Err(ChannelError::Close("Remote sent us a closing_signed with a fee greater than the value they can claim")); + return Err(ChannelError::Close(format!("Remote sent us a closing_signed with a fee greater than the value they can claim. Fee in message: {}", msg.fee_satoshis))); } let mut sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]); @@ -2872,7 +3026,7 @@ impl Channel { // limits, so check for that case by re-checking the signature here. closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0; sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]); - secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.their_funding_pubkey()), "Invalid closing tx signature from peer"); + secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.their_funding_pubkey()), "Invalid closing tx signature from peer".to_owned()); }, }; @@ -2888,10 +3042,10 @@ impl Channel { macro_rules! propose_new_feerate { ($new_feerate: expr) => { let closing_tx_max_weight = Self::get_closing_transaction_weight(&self.get_closing_scriptpubkey(), self.their_shutdown_scriptpubkey.as_ref().unwrap()); - let (closing_tx, used_total_fee) = self.build_closing_transaction($new_feerate * closing_tx_max_weight / 1000, false); + let (closing_tx, used_total_fee) = self.build_closing_transaction($new_feerate as u64 * closing_tx_max_weight / 1000, false); let our_sig = self.local_keys .sign_closing_transaction(&closing_tx, &self.secp_ctx) - .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction"))?; + .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?; self.last_sent_closing_fee = Some(($new_feerate, used_total_fee, our_sig.clone())); return Ok((Some(msgs::ClosingSigned { channel_id: self.channel_id, @@ -2901,23 +3055,23 @@ impl Channel { } } - let proposed_sat_per_kw = msg.fee_satoshis * 1000 / closing_tx.get_weight() as u64; + let proposed_sat_per_kw = msg.fee_satoshis * 1000 / closing_tx.get_weight() as u64; if self.channel_outbound { let our_max_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal); - if proposed_sat_per_kw > our_max_feerate { + if (proposed_sat_per_kw as u32) > our_max_feerate { if let Some((last_feerate, _, _)) = self.last_sent_closing_fee { if our_max_feerate <= last_feerate { - return Err(ChannelError::Close("Unable to come to consensus about closing feerate, remote wanted something higher than our Normal feerate")); + return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wanted something higher ({}) than our Normal feerate ({})", last_feerate, our_max_feerate))); } } propose_new_feerate!(our_max_feerate); } } else { let our_min_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background); - if proposed_sat_per_kw < our_min_feerate { + if (proposed_sat_per_kw as u32) < our_min_feerate { if let Some((last_feerate, _, _)) = self.last_sent_closing_fee { if our_min_feerate >= last_feerate { - return Err(ChannelError::Close("Unable to come to consensus about closing feerate, remote wanted something lower than our Background feerate")); + return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wanted something lower ({}) than our Background feerate ({}).", last_feerate, our_min_feerate))); } } propose_new_feerate!(our_min_feerate); @@ -2926,7 +3080,7 @@ impl Channel { let our_sig = self.local_keys .sign_closing_transaction(&closing_tx, &self.secp_ctx) - .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction"))?; + .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?; self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &our_sig); self.channel_state = ChannelState::ShutdownComplete as u32; @@ -2982,6 +3136,18 @@ impl Channel { self.our_htlc_minimum_msat } + /// Allowed in any state (including after shutdown) + pub fn get_announced_htlc_max_msat(&self) -> u64 { + return cmp::min( + // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts + // to use full capacity. This is an effort to reduce routing failures, because in many cases + // channel might have been used to route very small values (either by honest users or as DoS). + self.channel_value_satoshis * 9 / 10, + + Channel::::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis) + ); + } + /// Allowed in any state (including after shutdown) pub fn get_their_htlc_minimum_msat(&self) -> u64 { self.our_htlc_minimum_msat @@ -2996,7 +3162,7 @@ impl Channel { } #[cfg(test)] - pub fn get_feerate(&self) -> u64 { + pub fn get_feerate(&self) -> u32 { self.feerate_per_kw } @@ -3038,6 +3204,7 @@ impl Channel { res }, their_max_htlc_value_in_flight_msat: self.their_max_htlc_value_in_flight_msat, + their_dust_limit_msat: self.their_dust_limit_satoshis * 1000, } } @@ -3067,15 +3234,15 @@ impl Channel { // output value back into a transaction with the regular channel output: // the fee cost of the HTLC-Success/HTLC-Timeout transaction: - let mut res = self.feerate_per_kw * cmp::max(HTLC_TIMEOUT_TX_WEIGHT, HTLC_SUCCESS_TX_WEIGHT) / 1000; + let mut res = self.feerate_per_kw as u64 * cmp::max(HTLC_TIMEOUT_TX_WEIGHT, HTLC_SUCCESS_TX_WEIGHT) / 1000; if self.channel_outbound { // + the marginal fee increase cost to us in the commitment transaction: - res += self.feerate_per_kw * COMMITMENT_TX_WEIGHT_PER_HTLC / 1000; + res += self.feerate_per_kw as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC / 1000; } // + the marginal cost of an input which spends the HTLC-Success/HTLC-Timeout output: - res += fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) * SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT / 1000; + res += fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) as u64 * SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT / 1000; res as u32 } @@ -3154,7 +3321,7 @@ impl Channel { /// /// May return some HTLCs (and their payment_hash) which have timed out and should be failed /// back. - pub fn block_connected(&mut self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) -> Result<(Option, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> { + pub fn block_connected(&mut self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[usize]) -> Result<(Option, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> { let mut timed_out_htlcs = Vec::new(); self.holding_cell_htlc_updates.retain(|htlc_update| { match htlc_update { @@ -3205,6 +3372,10 @@ impl Channel { } } } + if height > 0xff_ff_ff || (*index_in_block) > 0xff_ff_ff { + panic!("Block was bogus - either height 16 million or had > 16 million transactions"); + } + assert!(txo_idx <= 0xffff); // txo_idx is a (u16 as usize), so this is just listed here for completeness self.funding_tx_confirmations = 1; self.short_channel_id = Some(((height as u64) << (5*8)) | ((*index_in_block as u64) << (2*8)) | @@ -3247,8 +3418,7 @@ impl Channel { //a protocol oversight, but I assume I'm just missing something. if need_commitment_update { if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 { - let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number); - let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret); + let next_per_commitment_point = self.local_keys.get_per_commitment_point(self.cur_local_commitment_transaction_number, &self.secp_ctx); return Ok((Some(msgs::FundingLocked { channel_id: self.channel_id, next_per_commitment_point: next_per_commitment_point, @@ -3287,9 +3457,7 @@ impl Channel { // Methods to get unprompted messages to send to the remote end (or where we already returned // something in the handler for the message that prompted this message): - pub fn get_open_channel(&self, chain_hash: BlockHash, fee_estimator: &F) -> msgs::OpenChannel - where F::Target: FeeEstimator - { + pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel { if !self.channel_outbound { panic!("Tried to open a channel for an inbound channel?"); } @@ -3301,7 +3469,8 @@ impl Channel { panic!("Tried to send an open_channel for a channel that has already advanced"); } - let local_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number); + let first_per_commitment_point = self.local_keys.get_per_commitment_point(self.cur_local_commitment_transaction_number, &self.secp_ctx); + let local_keys = self.local_keys.pubkeys(); msgs::OpenChannel { chain_hash: chain_hash, @@ -3312,15 +3481,15 @@ 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_remote_channel_reserve_satoshis(self.channel_value_satoshis), htlc_minimum_msat: self.our_htlc_minimum_msat, - feerate_per_kw: fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) as u32, + feerate_per_kw: self.feerate_per_kw as u32, to_self_delay: self.our_to_self_delay, max_accepted_htlcs: OUR_MAX_HTLCS, - funding_pubkey: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), - revocation_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.revocation_base_key()), - payment_point: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.payment_key()), - delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.delayed_payment_base_key()), - htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key()), - first_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &local_commitment_secret), + funding_pubkey: local_keys.funding_pubkey, + revocation_basepoint: local_keys.revocation_basepoint, + payment_point: local_keys.payment_point, + delayed_payment_basepoint: local_keys.delayed_payment_basepoint, + htlc_basepoint: local_keys.htlc_basepoint, + first_per_commitment_point, channel_flags: if self.config.announced_channel {1} else {0}, shutdown_scriptpubkey: OptionalField::Present(if self.config.commit_upfront_shutdown_pubkey { self.get_closing_scriptpubkey() } else { Builder::new().into_script() }) } @@ -3337,7 +3506,8 @@ impl Channel { panic!("Tried to send an accept_channel for a channel that has already advanced"); } - let local_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number); + let first_per_commitment_point = self.local_keys.get_per_commitment_point(self.cur_local_commitment_transaction_number, &self.secp_ctx); + let local_keys = self.local_keys.pubkeys(); msgs::AcceptChannel { temporary_channel_id: self.channel_id, @@ -3348,12 +3518,12 @@ impl Channel { minimum_depth: self.minimum_depth, to_self_delay: self.our_to_self_delay, max_accepted_htlcs: OUR_MAX_HTLCS, - funding_pubkey: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), - revocation_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.revocation_base_key()), - payment_point: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.payment_key()), - delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.delayed_payment_base_key()), - htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key()), - first_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &local_commitment_secret), + funding_pubkey: local_keys.funding_pubkey, + revocation_basepoint: local_keys.revocation_basepoint, + payment_point: local_keys.payment_point, + delayed_payment_basepoint: local_keys.delayed_payment_basepoint, + htlc_basepoint: local_keys.htlc_basepoint, + first_per_commitment_point, shutdown_scriptpubkey: OptionalField::Present(if self.config.commit_upfront_shutdown_pubkey { self.get_closing_scriptpubkey() } else { Builder::new().into_script() }) } } @@ -3362,8 +3532,8 @@ impl Channel { fn get_outbound_funding_created_signature(&mut self, logger: &L) -> Result where L::Target: Logger { let remote_keys = self.build_remote_transaction_keys()?; let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw, logger).0; - Ok(self.local_keys.sign_remote_commitment(self.feerate_per_kw, &remote_initial_commitment_tx, &remote_keys, &Vec::new(), self.our_to_self_delay, &self.secp_ctx) - .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed"))?.0) + Ok(self.local_keys.sign_remote_commitment(self.feerate_per_kw, &remote_initial_commitment_tx, &remote_keys, &Vec::new(), &self.secp_ctx) + .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0) } /// Updates channel state with knowledge of the funding transaction's txid/index, and generates @@ -3421,17 +3591,16 @@ impl Channel { /// https://github.com/lightningnetwork/lightning-rfc/issues/468 pub fn get_channel_announcement(&self, our_node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> { if !self.config.announced_channel { - return Err(ChannelError::Ignore("Channel is not available for public announcements")); + return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned())); } if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 { - return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked")); + return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked".to_owned())); } if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 { - return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing")); + return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing".to_owned())); } let were_node_one = our_node_id.serialize()[..] < self.their_node_id.serialize()[..]; - let our_bitcoin_key = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()); let msg = msgs::UnsignedChannelAnnouncement { features: ChannelFeatures::known(), @@ -3439,13 +3608,13 @@ impl Channel { short_channel_id: self.get_short_channel_id().unwrap(), node_id_1: if were_node_one { our_node_id } else { self.get_their_node_id() }, node_id_2: if were_node_one { self.get_their_node_id() } else { our_node_id }, - bitcoin_key_1: if were_node_one { our_bitcoin_key } else { self.their_funding_pubkey().clone() }, - bitcoin_key_2: if were_node_one { self.their_funding_pubkey().clone() } else { our_bitcoin_key }, + bitcoin_key_1: if were_node_one { self.local_keys.pubkeys().funding_pubkey } else { self.their_funding_pubkey().clone() }, + bitcoin_key_2: if were_node_one { self.their_funding_pubkey().clone() } else { self.local_keys.pubkeys().funding_pubkey }, excess_data: Vec::new(), }; let sig = self.local_keys.sign_channel_announcement(&msg, &self.secp_ctx) - .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement"))?; + .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement".to_owned()))?; Ok((msg, sig)) } @@ -3513,19 +3682,19 @@ impl Channel { /// If an Err is returned, it's a ChannelError::Ignore! pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result, ChannelError> { if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) { - return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down")); + return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned())); } - - if amount_msat > self.channel_value_satoshis * 1000 { - return Err(ChannelError::Ignore("Cannot send more than the total value of the channel")); + let channel_total_msat = self.channel_value_satoshis * 1000; + if amount_msat > channel_total_msat { + return Err(ChannelError::Ignore(format!("Cannot send amount {}, because it is more than the total value of the channel {}", amount_msat, channel_total_msat))); } if amount_msat == 0 { - return Err(ChannelError::Ignore("Cannot send 0-msat HTLC")); + return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned())); } if amount_msat < self.their_htlc_minimum_msat { - return Err(ChannelError::Ignore("Cannot send less than their minimum HTLC value")); + return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.their_htlc_minimum_msat))); } if (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 { @@ -3535,41 +3704,68 @@ impl Channel { // disconnected during the time the previous hop was doing the commitment dance we may // end up getting here after the forwarding delay. In any case, returning an // IgnoreError will get ChannelManager to do the right thing and fail backwards now. - return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update")); + return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update".to_owned())); } let (outbound_htlc_count, htlc_outbound_value_msat) = self.get_outbound_pending_htlc_stats(); if outbound_htlc_count + 1 > self.their_max_accepted_htlcs as u32 { - return Err(ChannelError::Ignore("Cannot push more than their max accepted HTLCs")); + return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.their_max_accepted_htlcs))); } // Check their_max_htlc_value_in_flight_msat if htlc_outbound_value_msat + amount_msat > self.their_max_htlc_value_in_flight_msat { - return Err(ChannelError::Ignore("Cannot send value that would put us over the max HTLC value in flight our peer will accept")); + return Err(ChannelError::Ignore(format!("Cannot send value that would put us over the max HTLC value in flight our peer will accept ({})", self.their_max_htlc_value_in_flight_msat))); + } + + if !self.channel_outbound { + // Check that we won't violate the remote channel reserve by adding this HTLC. + + let remote_balance_msat = self.channel_value_satoshis * 1000 - self.value_to_self_msat; + let remote_chan_reserve_msat = Channel::::get_remote_channel_reserve_satoshis(self.channel_value_satoshis); + // 1 additional HTLC corresponding to this HTLC. + let remote_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(1); + if remote_balance_msat < remote_chan_reserve_msat + remote_commit_tx_fee_msat { + return Err(ChannelError::Ignore("Cannot send value that would put them under remote channel reserve value".to_owned())); + } + } + + let pending_value_to_self_msat = self.value_to_self_msat - htlc_outbound_value_msat; + if pending_value_to_self_msat < amount_msat { + return Err(ChannelError::Ignore(format!("Cannot send value that would overdraw remaining funds. Amount: {}, pending value to self {}", amount_msat, pending_value_to_self_msat))); + } + + // The `+1` is for the HTLC currently being added to the commitment tx and + // the `2 *` and `+1` are for the fee spike buffer. + let local_commit_tx_fee_msat = if self.channel_outbound { + 2 * self.next_local_commit_tx_fee_msat(1 + 1) + } else { 0 }; + if pending_value_to_self_msat - amount_msat < local_commit_tx_fee_msat { + return Err(ChannelError::Ignore(format!("Cannot send value that would not leave enough to pay for fees. Pending value to self: {}. local_commit_tx_fee {}", pending_value_to_self_msat, local_commit_tx_fee_msat))); } // Check self.local_channel_reserve_satoshis (the amount we must keep as // reserve for the remote to have something to claim if we misbehave) - if self.value_to_self_msat < self.local_channel_reserve_satoshis * 1000 + amount_msat + htlc_outbound_value_msat { - return Err(ChannelError::Ignore("Cannot send value that would put us under local channel reserve value")); + let chan_reserve_msat = self.local_channel_reserve_satoshis * 1000; + if pending_value_to_self_msat - amount_msat - local_commit_tx_fee_msat < chan_reserve_msat { + return Err(ChannelError::Ignore(format!("Cannot send value that would put us under local channel reserve value ({})", chan_reserve_msat))); } // Now update local state: if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) { self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC { - amount_msat: amount_msat, - payment_hash: payment_hash, - cltv_expiry: cltv_expiry, + amount_msat, + payment_hash, + cltv_expiry, source, - onion_routing_packet: onion_routing_packet, + onion_routing_packet, }); return Ok(None); } self.pending_outbound_htlcs.push(OutboundHTLCOutput { htlc_id: self.next_local_htlc_id, - amount_msat: amount_msat, + amount_msat, payment_hash: payment_hash.clone(), - cltv_expiry: cltv_expiry, + cltv_expiry, state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())), source, }); @@ -3577,10 +3773,10 @@ impl Channel { let res = msgs::UpdateAddHTLC { channel_id: self.channel_id, htlc_id: self.next_local_htlc_id, - amount_msat: amount_msat, - payment_hash: payment_hash, - cltv_expiry: cltv_expiry, - onion_routing_packet: onion_routing_packet, + amount_msat, + payment_hash, + cltv_expiry, + onion_routing_packet, }; self.next_local_htlc_id += 1; @@ -3689,8 +3885,8 @@ impl Channel { htlcs.push(htlc); } - let res = self.local_keys.sign_remote_commitment(feerate_per_kw, &remote_commitment_tx.0, &remote_keys, &htlcs, self.our_to_self_delay, &self.secp_ctx) - .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed"))?; + let res = self.local_keys.sign_remote_commitment(feerate_per_kw, &remote_commitment_tx.0, &remote_keys, &htlcs, &self.secp_ctx) + .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?; signature = res.0; htlc_signatures = res.1; @@ -3734,20 +3930,20 @@ impl Channel { pub fn get_shutdown(&mut self) -> Result<(msgs::Shutdown, Vec<(HTLCSource, PaymentHash)>), APIError> { for htlc in self.pending_outbound_htlcs.iter() { if let OutboundHTLCState::LocalAnnounced(_) = htlc.state { - return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first"}); + return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()}); } } if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 { if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 { - return Err(APIError::APIMisuseError{err: "Shutdown already in progress"}); + return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()}); } else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 { - return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote"}); + return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()}); } } assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0); if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 { - return Err(APIError::ChannelUnavailable{err: "Cannot begin shutdown while peer is disconnected or we're waiting on a monitor update, maybe force-close instead?"}); + return Err(APIError::ChannelUnavailable{err: "Cannot begin shutdown while peer is disconnected or we're waiting on a monitor update, maybe force-close instead?".to_owned()}); } let our_closing_script = self.get_closing_scriptpubkey(); @@ -4307,13 +4503,12 @@ mod tests { use bitcoin::hashes::Hash; use bitcoin::hash_types::{Txid, WPubkeyHash}; use std::sync::Arc; - use rand::{thread_rng,Rng}; struct TestFeeEstimator { - fee_est: u64 + fee_est: u32 } impl FeeEstimator for TestFeeEstimator { - fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u64 { + fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 { self.fee_est } } @@ -4355,14 +4550,34 @@ mod tests { PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap()) } + // Check that, during channel creation, we use the same feerate in the open channel message + // as we do in the Channel object creation itself. + #[test] + fn test_open_channel_msg_fee() { + let original_fee = 253; + let mut fee_est = TestFeeEstimator{fee_est: original_fee }; + let secp_ctx = Secp256k1::new(); + let seed = [42; 32]; + let network = Network::Testnet; + let keys_provider = test_utils::TestKeysInterface::new(&seed, network); + + let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()); + let config = UserConfig::default(); + let node_a_chan = Channel::::new_outbound(&&fee_est, &&keys_provider, node_a_node_id, 10000000, 100000, 42, &config).unwrap(); + + // Now change the fee so we can check that the fee in the open_channel message is the + // same as the old fee. + fee_est.fee_est = 500; + let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.bitcoin_hash()); + assert_eq!(open_channel_msg.feerate_per_kw, original_fee); + } + #[test] fn channel_reestablish_no_updates() { let feeest = TestFeeEstimator{fee_est: 15000}; let logger = test_utils::TestLogger::new(); let secp_ctx = Secp256k1::new(); - let mut seed = [0; 32]; - let mut rng = thread_rng(); - rng.fill_bytes(&mut seed); + let seed = [42; 32]; let network = Network::Testnet; let keys_provider = test_utils::TestKeysInterface::new(&seed, network); @@ -4374,7 +4589,7 @@ mod tests { let mut node_a_chan = Channel::::new_outbound(&&feeest, &&keys_provider, node_a_node_id, 10000000, 100000, 42, &config).unwrap(); // Create Node B's channel by receiving Node A's open_channel message - let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.bitcoin_hash(), &&feeest); + let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.bitcoin_hash()); let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap()); let mut node_b_chan = Channel::::new_from_req(&&feeest, &&keys_provider, node_b_node_id, InitFeatures::known(), &open_channel_msg, 7, &config).unwrap(); @@ -4442,7 +4657,7 @@ mod tests { (0, 0) ); - assert_eq!(PublicKey::from_secret_key(&secp_ctx, chan_keys.funding_key()).serialize()[..], + assert_eq!(chan_keys.pubkeys().funding_pubkey.serialize()[..], hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]); let keys_provider = Keys { chan_keys: chan_keys.clone() }; @@ -4463,7 +4678,7 @@ mod tests { delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"), htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444") }; - chan_keys.set_remote_channel_pubkeys(&their_pubkeys); + chan_keys.on_accept(&their_pubkeys, chan.their_to_self_delay, chan.our_to_self_delay); assert_eq!(their_pubkeys.payment_point.serialize()[..], hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]); @@ -4477,11 +4692,11 @@ mod tests { // We can't just use build_local_transaction_keys here as the per_commitment_secret is not // derived from a commitment_seed, so instead we copy it here and call // build_commitment_transaction. - let delayed_payment_base = PublicKey::from_secret_key(&secp_ctx, chan.local_keys.delayed_payment_base_key()); + let delayed_payment_base = &chan.local_keys.pubkeys().delayed_payment_basepoint; let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap(); let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret); - let htlc_basepoint = PublicKey::from_secret_key(&secp_ctx, chan.local_keys.htlc_base_key()); - let keys = TxCreationKeys::new(&secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &their_pubkeys.revocation_basepoint, &their_pubkeys.htlc_basepoint).unwrap(); + let htlc_basepoint = &chan.local_keys.pubkeys().htlc_basepoint; + let keys = TxCreationKeys::new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &their_pubkeys.revocation_basepoint, &their_pubkeys.htlc_basepoint).unwrap(); chan.their_pubkeys = Some(their_pubkeys); @@ -4512,14 +4727,14 @@ mod tests { })* assert_eq!(unsigned_tx.1.len(), per_htlc.len()); - localtx = LocalCommitmentTransaction::new_missing_local_sig(unsigned_tx.0.clone(), their_signature.clone(), &PublicKey::from_secret_key(&secp_ctx, chan.local_keys.funding_key()), chan.their_funding_pubkey(), keys.clone(), chan.feerate_per_kw, per_htlc); + localtx = LocalCommitmentTransaction::new_missing_local_sig(unsigned_tx.0.clone(), their_signature.clone(), &chan_keys.pubkeys().funding_pubkey, chan.their_funding_pubkey(), keys.clone(), chan.feerate_per_kw, per_htlc); let local_sig = chan_keys.sign_local_commitment(&localtx, &chan.secp_ctx).unwrap(); assert_eq!(Signature::from_der(&hex::decode($our_sig_hex).unwrap()[..]).unwrap(), local_sig); assert_eq!(serialize(&localtx.add_local_sig(&redeemscript, local_sig))[..], hex::decode($tx_hex).unwrap()[..]); - let htlc_sigs = chan_keys.sign_local_commitment_htlc_transactions(&localtx, chan.their_to_self_delay, &chan.secp_ctx).unwrap(); + let htlc_sigs = chan_keys.sign_local_commitment_htlc_transactions(&localtx, &chan.secp_ctx).unwrap(); let mut htlc_sig_iter = localtx.per_htlc.iter().zip(htlc_sigs.iter().enumerate()); $({