From: Antoine Riard Date: Fri, 21 Feb 2020 00:20:29 +0000 (-0500) Subject: BOLT2: Check we don't send and accept 0-msat HTLC X-Git-Tag: v0.0.12~105^2~3 X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=d1c6f235f9e432785150bd72c6ba6731e8f75c85;p=rust-lightning BOLT2: Check we don't send and accept 0-msat HTLC Failing this requirement at sending means a strict receiver would fail our channel while processing a HTLC routed from a third-party. Fix by enforcing check on both sender and receiver side. --- diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs index 8b5d9120b..5771f772e 100644 --- a/lightning/src/ln/channel.rs +++ b/lightning/src/ln/channel.rs @@ -1656,6 +1656,9 @@ impl Channel { 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")); } + if msg.amount_msat == 0 { + return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC")); + } if msg.amount_msat < self.our_htlc_minimum_msat { return Err(ChannelError::Close("Remote side tried to send less than our minimum HTLC value")); } @@ -3493,6 +3496,11 @@ impl Channel { if amount_msat > self.channel_value_satoshis * 1000 { return Err(ChannelError::Ignore("Cannot send more than the total value of the channel")); } + + if amount_msat == 0 { + return Err(ChannelError::Ignore("Cannot send 0-msat HTLC")); + } + if amount_msat < self.their_htlc_minimum_msat { return Err(ChannelError::Ignore("Cannot send less than their minimum HTLC value")); } diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs index a41ae11af..4dc7e5e12 100644 --- a/lightning/src/ln/functional_tests.rs +++ b/lightning/src/ln/functional_tests.rs @@ -5486,7 +5486,6 @@ fn bolt2_open_channel_sending_node_checks_part2() { #[test] fn test_update_add_htlc_bolt2_sender_value_below_minimum_msat() { - //BOLT2 Requirement: MUST offer amount_msat greater than 0. //BOLT2 Requirement: MUST NOT offer amount_msat below the receiving node's htlc_minimum_msat (same validation check catches both of these) let chanmon_cfgs = create_chanmon_cfgs(2); let node_cfgs = create_node_cfgs(2, &chanmon_cfgs); @@ -5496,7 +5495,7 @@ fn test_update_add_htlc_bolt2_sender_value_below_minimum_msat() { let mut route = nodes[0].router.get_route(&nodes[1].node.get_our_node_id(), None, &[], 100000, TEST_FINAL_CLTV).unwrap(); let (_, our_payment_hash) = get_payment_preimage_hash!(nodes[0]); - route.hops[0].fee_msat = 0; + route.hops[0].fee_msat = 100; let err = nodes[0].node.send_payment(route, our_payment_hash); @@ -5509,6 +5508,30 @@ fn test_update_add_htlc_bolt2_sender_value_below_minimum_msat() { nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Cannot send less than their minimum HTLC value".to_string(), 1); } +#[test] +fn test_update_add_htlc_bolt2_sender_zero_value_msat() { + //BOLT2 Requirement: MUST offer amount_msat greater than 0. + let chanmon_cfgs = create_chanmon_cfgs(2); + let node_cfgs = create_node_cfgs(2, &chanmon_cfgs); + let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]); + let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs); + let _chan = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 95000000, InitFeatures::supported(), InitFeatures::supported()); + let mut route = nodes[0].router.get_route(&nodes[1].node.get_our_node_id(), None, &[], 100000, TEST_FINAL_CLTV).unwrap(); + let (_, our_payment_hash) = get_payment_preimage_hash!(nodes[0]); + + route.hops[0].fee_msat = 0; + + let err = nodes[0].node.send_payment(route, our_payment_hash); + + if let Err(APIError::ChannelUnavailable{err}) = err { + assert_eq!(err, "Cannot send 0-msat HTLC"); + } else { + assert!(false); + } + assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty()); + nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Cannot send 0-msat HTLC".to_string(), 1); +} + #[test] fn test_update_add_htlc_bolt2_sender_cltv_expiry_too_high() { //BOLT 2 Requirement: MUST set cltv_expiry less than 500000000.