use chain::chaininterface::{BroadcasterInterface,ChainListener,ChainWatchInterface,FeeEstimator};
use chain::transaction::OutPoint;
use ln::channel::{Channel, ChannelError, ChannelKeys};
-use ln::channelmonitor::ManyChannelMonitor;
+use ln::channelmonitor::{ManyChannelMonitor, CLTV_CLAIM_BUFFER, HTLC_FAIL_TIMEOUT_BLOCKS};
use ln::router::{Route,RouteHop};
use ln::msgs;
use ln::msgs::{HandleError,ChannelMessageHandler};
logger: Arc<Logger>,
}
+/// The minimum number of blocks between an inbound HTLC's CLTV and the corresponding outbound
+/// HTLC's CLTV. This should always be a few blocks greater than channelmonitor::CLTV_CLAIM_BUFFER,
+/// ie the node we forwarded the payment on to should always have enough room to reliably time out
+/// the HTLC via a full update_fail_htlc/commitment_signed dance before we hit the
+/// CLTV_CLAIM_BUFFER point (we static assert that its at least 3 blocks more).
const CLTV_EXPIRY_DELTA: u16 = 6 * 24 * 2; //TODO?
+const CLTV_FAR_FAR_AWAY: u32 = 6 * 24 * 7; //TODO?
+
+// Check that our CLTV_EXPIRY is at least CLTV_CLAIM_BUFFER + 2*HTLC_FAIL_TIMEOUT_BLOCKS, ie that
+// if the next-hop peer fails the HTLC within HTLC_FAIL_TIMEOUT_BLOCKS then we'll still have
+// HTLC_FAIL_TIMEOUT_BLOCKS left to fail it backwards ourselves before hitting the
+// CLTV_CLAIM_BUFFER point and failing the channel on-chain to time out the HTLC.
+#[deny(const_err)]
+#[allow(dead_code)]
+const CHECK_CLTV_EXPIRY_SANITY: u32 = CLTV_EXPIRY_DELTA as u32 - 2*HTLC_FAIL_TIMEOUT_BLOCKS - CLTV_CLAIM_BUFFER;
+
+// Check for ability of an attacker to make us fail on-chain by delaying inbound claim. See
+// ChannelMontior::would_broadcast_at_height for a description of why this is needed.
+#[deny(const_err)]
+#[allow(dead_code)]
+const CHECK_CLTV_EXPIRY_SANITY_2: u32 = CLTV_EXPIRY_DELTA as u32 - HTLC_FAIL_TIMEOUT_BLOCKS - 2*CLTV_CLAIM_BUFFER;
macro_rules! secp_call {
( $res: expr, $err: expr ) => {
}
};
- //TODO: Check that msg.cltv_expiry is within acceptable bounds!
-
let pending_forward_info = if next_hop_data.hmac == [0; 32] {
// OUR PAYMENT!
- if next_hop_data.data.amt_to_forward != msg.amount_msat {
+ // final_expiry_too_soon
+ if (msg.cltv_expiry as u64) < self.latest_block_height.load(Ordering::Acquire) as u64 + (CLTV_CLAIM_BUFFER + HTLC_FAIL_TIMEOUT_BLOCKS) as u64 {
+ return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
+ }
+ // final_incorrect_htlc_amount
+ 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));
}
+ // final_incorrect_cltv_expiry
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 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() { // channel_disabled
+ break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, Some(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, Some(self.get_channel_update(chan).unwrap())));
+ }
+ 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, Some(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, Some(self.get_channel_update(chan).unwrap())));
}
- } {
- return_err!(err, code, &chan_update.encode_with_len()[..]);
+ let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
+ // We want to have at least HTLC_FAIL_TIMEOUT_BLOCKS to fail prior to going on chain CLAIM_BUFFER blocks before expiration
+ if msg.cltv_expiry <= cur_height + CLTV_CLAIM_BUFFER + HTLC_FAIL_TIMEOUT_BLOCKS as u32 { // expiry_too_soon
+ break Some(("CLTV expiry is too close", 0x1000 | 14, Some(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", 21, None));
+ }
+ 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(msg.amount_msat));
+ }
+ else if code == 0x1000 | 13 {
+ res.extend_from_slice(&byte_utils::be32_to_array(msg.cltv_expiry));
+ }
+ if let Some(chan_update) = chan_update {
+ res.extend_from_slice(&chan_update.encode_with_len()[..]);
+ }
+ return_err!(err, code, &res[..]);
}
}
}
/// Indicates that the preimage for payment_hash is unknown after a PaymentReceived event.
pub fn fail_htlc_backwards(&self, payment_hash: &[u8; 32]) -> bool {
+ // TODO: Add ability to return 0x4000|16 (incorrect_payment_amount) if the amount we
+ // received is < expected or > 2*expected
let mut channel_state = Some(self.channel_state.lock().unwrap());
let removed_source = channel_state.as_mut().unwrap().claimable_htlcs.remove(payment_hash);
if let Some(mut sources) = removed_source {
// No such next-hop. We know this came from the
// current node as the HMAC validated.
res = Some(msgs::HTLCFailChannelUpdate::ChannelClosed {
- short_channel_id: route_hop.short_channel_id
+ short_channel_id: route_hop.short_channel_id,
+ is_permanent: true,
});
},
_ => {}, //TODO: Enumerate all of these!
use chain::transaction::OutPoint;
use chain::chaininterface::ChainListener;
use ln::channelmanager::{ChannelManager,OnionKeys};
+ use ln::channelmonitor::{CLTV_CLAIM_BUFFER, HTLC_FAIL_TIMEOUT_BLOCKS};
use ln::router::{Route, RouteHop, Router};
use ln::msgs;
use ln::msgs::{ChannelMessageHandler,RoutingMessageHandler};
use std::default::Default;
use std::rc::Rc;
use std::sync::{Arc, Mutex};
+ use std::sync::atomic::Ordering;
use std::time::Instant;
use std::mem;
assert_eq!(nodes[2].node.list_channels().len(), 0);
assert_eq!(nodes[3].node.list_channels().len(), 1);
+ { // Cheat and reset nodes[4]'s height to 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);
+ }
+
+ assert_eq!(nodes[3].node.latest_block_height.load(Ordering::Acquire), 1);
+ assert_eq!(nodes[4].node.latest_block_height.load(Ordering::Acquire), 1);
// One pending HTLC to time out:
let payment_preimage_2 = route_payment(&nodes[3], &vec!(&nodes[4])[..], 3000000).0;
+ // CLTV expires at TEST_FINAL_CLTV + 1 (current height) + 1 (added in send_payment for
+ // buffer space).
{
let mut header = BlockHeader { version: 0x20000000, prev_blockhash: Default::default(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
- nodes[3].chain_monitor.block_connected_checked(&header, 1, &Vec::new()[..], &[0; 0]);
- for i in 2..TEST_FINAL_CLTV - 3 {
+ nodes[3].chain_monitor.block_connected_checked(&header, 2, &Vec::new()[..], &[0; 0]);
+ for i in 3..TEST_FINAL_CLTV + 2 + HTLC_FAIL_TIMEOUT_BLOCKS + 1 {
header = BlockHeader { version: 0x20000000, prev_blockhash: header.bitcoin_hash(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
nodes[3].chain_monitor.block_connected_checked(&header, i, &Vec::new()[..], &[0; 0]);
}
claim_funds!(nodes[4], nodes[3], payment_preimage_2);
header = BlockHeader { version: 0x20000000, prev_blockhash: Default::default(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
- nodes[4].chain_monitor.block_connected_checked(&header, 1, &Vec::new()[..], &[0; 0]);
- for i in 2..TEST_FINAL_CLTV - 3 {
+ nodes[4].chain_monitor.block_connected_checked(&header, 2, &Vec::new()[..], &[0; 0]);
+ for i in 3..TEST_FINAL_CLTV + 2 - CLTV_CLAIM_BUFFER + 1 {
header = BlockHeader { version: 0x20000000, prev_blockhash: header.bitcoin_hash(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
nodes[4].chain_monitor.block_connected_checked(&header, i, &Vec::new()[..], &[0; 0]);
}
let as_chan = a_channel_lock.by_id.get(&chan_announcement.3).unwrap();
let bs_chan = b_channel_lock.by_id.get(&chan_announcement.3).unwrap();
- let _ = nodes[0].router.handle_htlc_fail_channel_update(&msgs::HTLCFailChannelUpdate::ChannelClosed { short_channel_id : as_chan.get_short_channel_id().unwrap() } );
+ let _ = nodes[0].router.handle_htlc_fail_channel_update(&msgs::HTLCFailChannelUpdate::ChannelClosed { short_channel_id : as_chan.get_short_channel_id().unwrap(), is_permanent: false } );
let as_bitcoin_key = PublicKey::from_secret_key(&secp_ctx, &as_chan.get_local_keys().funding_key);
let bs_bitcoin_key = PublicKey::from_secret_key(&secp_ctx, &bs_chan.get_local_keys().funding_key);
let unsigned_msg = dummy_unsigned_msg!();
sign_msg!(unsigned_msg);
assert_eq!(nodes[0].router.handle_channel_announcement(&chan_announcement).unwrap(), true);
- let _ = nodes[0].router.handle_htlc_fail_channel_update(&msgs::HTLCFailChannelUpdate::ChannelClosed { short_channel_id : as_chan.get_short_channel_id().unwrap() } );
+ let _ = nodes[0].router.handle_htlc_fail_channel_update(&msgs::HTLCFailChannelUpdate::ChannelClosed { short_channel_id : as_chan.get_short_channel_id().unwrap(), is_permanent: false } );
// Configured with Network::Testnet
let mut unsigned_msg = dummy_unsigned_msg!();
projects / rust-lightning / blobdiff