From 20dc143cfa4055af468730d2986041aeae0f525f Mon Sep 17 00:00:00 2001 From: Yuntai Kyong Date: Sun, 14 Oct 2018 22:30:21 +0900 Subject: [PATCH] Error handling in decoding onion --- src/ln/channel.rs | 5 ++++ src/ln/channelmanager.rs | 63 ++++++++++++++++++++++++++++------------ 2 files changed, 49 insertions(+), 19 deletions(-) diff --git a/src/ln/channel.rs b/src/ln/channel.rs index 1d736d41d..894ecdc19 100644 --- a/src/ln/channel.rs +++ b/src/ln/channel.rs @@ -2369,6 +2369,11 @@ impl Channel { self.our_htlc_minimum_msat } + /// Allowed in any state (including after shutdown) + pub fn get_their_htlc_minimum_msat(&self) -> u64 { + self.our_htlc_minimum_msat + } + pub fn get_value_satoshis(&self) -> u64 { self.channel_value_satoshis } diff --git a/src/ln/channelmanager.rs b/src/ln/channelmanager.rs index 07ea87f9d..806d056dd 100644 --- a/src/ln/channelmanager.rs +++ b/src/ln/channelmanager.rs @@ -291,6 +291,8 @@ pub struct ChannelManager { } const CLTV_EXPIRY_DELTA: u16 = 6 * 24 * 2; //TODO? +const CLTV_FAR_FAR_AWAY: u16 = 6 * 24 * 7; //TODO? +const FINAL_NODE_TIMEOUT: u16 = 3; //TODO? macro_rules! secp_call { ( $res: expr, $err: expr ) => { @@ -878,12 +880,15 @@ impl ChannelManager { let pending_forward_info = if next_hop_data.hmac == [0; 32] { // OUR PAYMENT! - if next_hop_data.data.amt_to_forward != msg.amount_msat { - return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat)); + if (msg.cltv_expiry as u64) < self.latest_block_height.load(Ordering::Acquire) as u64 + FINAL_NODE_TIMEOUT as u64 { // final_expiry_too_soon + return_err!("The CLTV expiry is too soon to handle", 17, &[0;0]); } if next_hop_data.data.outgoing_cltv_value != msg.cltv_expiry { return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry)); } + if next_hop_data.data.amt_to_forward != msg.amount_msat { + return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat)); + } // Note that we could obviously respond immediately with an update_fulfill_htlc // message, however that would leak that we are the recipient of this payment, so @@ -945,29 +950,46 @@ impl ChannelManager { if onion_packet.is_some() { // If short_channel_id is 0 here, we'll reject them in the body here let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned(); let forwarding_id = match id_option { - None => { + None => { // unknown_next_peer return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]); }, Some(id) => id.clone(), }; - if let Some((err, code, chan_update)) = { + if let Some((err, code, chan_update)) = loop { let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap(); - if !chan.is_live() { - Some(("Forwarding channel is not in a ready state.", 0x1000 | 7, self.get_channel_update(chan).unwrap())) - } else { - let fee = amt_to_forward.checked_mul(self.fee_proportional_millionths as u64).and_then(|prop_fee| { (prop_fee / 1000000).checked_add(chan.get_our_fee_base_msat(&*self.fee_estimator) as u64) }); - if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { - Some(("Prior hop has deviated from specified fees parameters or origin node has obsolete ones", 0x1000 | 12, self.get_channel_update(chan).unwrap())) - } else { - if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 { - Some(("Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta", 0x1000 | 13, self.get_channel_update(chan).unwrap())) - } else { - None - } - } + + if !chan.is_live() { // temporary_channel_failure + break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, self.get_channel_update(chan).unwrap())); + } + if *amt_to_forward < chan.get_their_htlc_minimum_msat() { // amount_below_minimum + break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, self.get_channel_update(chan).unwrap())); } - } { - return_err!(err, code, &chan_update.encode_with_len()[..]); + let fee = amt_to_forward.checked_mul(self.fee_proportional_millionths as u64).and_then(|prop_fee| { (prop_fee / 1000000).checked_add(chan.get_our_fee_base_msat(&*self.fee_estimator) as u64) }); + if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward { // fee_insufficient + break Some(("Prior hop has deviated from specified fees parameters or origin node has obsolete ones", 0x1000 | 12, self.get_channel_update(chan).unwrap())); + } + if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 { // incorrect_cltv_expiry + break Some(("Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta", 0x1000 | 13, self.get_channel_update(chan).unwrap())); + } + let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1; + if msg.cltv_expiry <= cur_height + 3 as u32 { // expiry_too_soon + break Some(("CLTV expiry is too close", 0x1000 | 14, self.get_channel_update(chan).unwrap())); + } + if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far + break Some(("CLTV expiry is too far in the future", 0x1000 | 21, self.get_channel_update(chan).unwrap())); + } + break None; + } + { + let mut res = Vec::with_capacity(8 + 128); + if code == 0x1000 | 11 || code == 0x1000 | 12 { + res.extend_from_slice(&byte_utils::be64_to_array(*amt_to_forward)); + } + else if code == 0x1000 | 13 { + res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry)); + } + res.extend_from_slice(&chan_update.encode_with_len()[..]); + return_err!(err, code, &res[..]); } } } @@ -4193,6 +4215,9 @@ mod tests { assert_eq!(nodes[0].node.list_channels().len(), 0); assert_eq!(nodes[1].node.list_channels().len(), 1); + let header = BlockHeader { version: 0x20000000, prev_blockhash: Default::default(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 }; + nodes[4].chain_monitor.block_connected_with_filtering(&Block { header, txdata: vec![] }, 1); + // One pending HTLC is discarded by the force-close: let payment_preimage_1 = route_payment(&nodes[1], &vec!(&nodes[2], &nodes[3])[..], 3000000).0; -- 2.39.5