short_to_id: HashMap<u64, [u8; 32]>,
next_forward: Instant,
/// short channel id -> forward infos. Key of 0 means payments received
+ /// Note that while this is held in the same mutex as the channels themselves, no consistency
+ /// guarantees are made about there existing a channel with the short id here, nor the short
+ /// ids in the PendingForwardHTLCInfo!
forward_htlcs: HashMap<u64, Vec<PendingForwardHTLCInfo>>,
+ /// Note that while this is held in the same mutex as the channels themselves, no consistency
+ /// guarantees are made about the channels given here actually existing anymore by the time you
+ /// go to read them!
claimable_htlcs: HashMap<[u8; 32], PendingOutboundHTLC>,
}
struct MutChannelHolder<'a> {
by_id: &'a mut HashMap<[u8; 32], Channel>,
short_to_id: &'a mut HashMap<u64, [u8; 32]>,
next_forward: &'a mut Instant,
- /// short channel id -> forward infos. Key of 0 means payments received
forward_htlcs: &'a mut HashMap<u64, Vec<PendingForwardHTLCInfo>>,
claimable_htlcs: &'a mut HashMap<[u8; 32], PendingOutboundHTLC>,
}
/// Sends a payment along a given route.
/// Value parameters are provided via the last hop in route, see documentation for RouteHop
/// fields for more info.
+ /// Note that if the payment_hash already exists elsewhere (eg you're sending a duplicative
+ /// payment), we don't do anything to stop you! We always try to ensure that if the provided
+ /// next hop knows the preimage to payment_hash they can claim an additional amount as
+ /// specified in the last hop in the route! Thus, you should probably do your own
+ /// payment_preimage tracking (which you should already be doing as they represent "proof of
+ /// payment") and prevent double-sends yourself.
/// See-also docs on Channel::send_htlc_and_commit.
/// May generate a SendHTLCs event on success, which should be relayed.
pub fn send_payment(&self, route: Route, payment_hash: [u8; 32]) -> Result<(), HandleError> {
let onion_packet = ChannelManager::construct_onion_packet(onion_payloads, onion_keys, &payment_hash)?;
let (first_hop_node_id, (update_add, commitment_signed, chan_monitor)) = {
- let mut channel_state = self.channel_state.lock().unwrap();
+ let mut channel_state_lock = self.channel_state.lock().unwrap();
+ let channel_state = channel_state_lock.borrow_parts();
+
let id = match channel_state.short_to_id.get(&route.hops.first().unwrap().short_channel_id) {
None => return Err(HandleError{err: "No channel available with first hop!", action: None}),
Some(id) => id.clone()
};
+
+ let claimable_htlc_entry = channel_state.claimable_htlcs.entry(payment_hash.clone());
+ if let hash_map::Entry::Occupied(_) = claimable_htlc_entry {
+ return Err(HandleError{err: "Already had pending HTLC with the same payment_hash", action: None});
+ }
+
let res = {
let chan = channel_state.by_id.get_mut(&id).unwrap();
if chan.get_their_node_id() != route.hops.first().unwrap().pubkey {
return Err(HandleError{err: "Node ID mismatch on first hop!", action: None});
}
- chan.send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, onion_packet)?
+ chan.send_htlc_and_commit(htlc_msat, payment_hash, htlc_cltv, onion_packet)?
};
let first_hop_node_id = route.hops.first().unwrap().pubkey;
- if channel_state.claimable_htlcs.insert(payment_hash, PendingOutboundHTLC::OutboundRoute {
+ claimable_htlc_entry.or_insert(PendingOutboundHTLC::OutboundRoute {
route,
session_priv,
- }).is_some() {
- // TODO: We need to track these better, we're not generating these, so a
- // third-party might make this happen:
- panic!("payment_hash was repeated! Don't let this happen");
- }
+ });
match res {
Some(msgs) => (first_hop_node_id, msgs),
self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: Vec::new() })
}
+ /// Fails an HTLC backwards to the sender of it to us.
+ /// Note that while we take a channel_state lock as input, we do *not* assume consistency here.
+ /// There are several callsites that do stupid things like loop over a list of payment_hashes
+ /// to fail and take the channel_state lock for each iteration (as we take ownership and may
+ /// drop it). In other words, no assumptions are made that entries in claimable_htlcs point to
+ /// still-available channels.
fn fail_htlc_backwards_internal(&self, mut channel_state: MutexGuard<ChannelHolder>, payment_hash: &[u8; 32], onion_error: HTLCFailReason) -> bool {
let mut pending_htlc = {
match channel_state.claimable_htlcs.remove(payment_hash) {
}
match pending_htlc {
- PendingOutboundHTLC::CycledRoute { .. } => { panic!("WAT"); },
+ PendingOutboundHTLC::CycledRoute { .. } => unreachable!(),
PendingOutboundHTLC::OutboundRoute { .. } => {
mem::drop(channel_state);
}
match pending_htlc {
- PendingOutboundHTLC::CycledRoute { .. } => { panic!("WAT"); },
+ PendingOutboundHTLC::CycledRoute { .. } => unreachable!(),
PendingOutboundHTLC::OutboundRoute { .. } => {
if from_user {
panic!("Called claim_funds with a preimage for an outgoing payment. There is nothing we can do with this, and something is seriously wrong if you knew this...");
let (node_id, fulfill_msgs) = {
let chan_id = match channel_state.short_to_id.get(&source_short_channel_id) {
Some(chan_id) => chan_id.clone(),
- None => return false
+ None => {
+ // TODO: There is probably a channel manager somewhere that needs to
+ // learn the preimage as the channel already hit the chain and that's
+ // why its missing.
+ return false
+ }
};
let chan = channel_state.by_id.get_mut(&chan_id).unwrap();
match chan.get_update_fulfill_htlc_and_commit(payment_preimage) {
Ok(msg) => (chan.get_their_node_id(), msg),
Err(_e) => {
+ // TODO: There is probably a channel manager somewhere that needs to
+ // learn the preimage as the channel may be about to hit the chain.
//TODO: Do something with e?
return false;
},
};
mem::drop(channel_state);
- match fulfill_msgs {
- Some((msg, commitment_msg, chan_monitor)) => {
- if let Err(_e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
- unimplemented!();// but def dont push the event...
- }
+ if let Some(chan_monitor) = fulfill_msgs.1 {
+ if let Err(_e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
+ unimplemented!();// but def dont push the event...
+ }
+ }
- let mut pending_events = self.pending_events.lock().unwrap();
- pending_events.push(events::Event::SendFulfillHTLC {
- node_id: node_id,
- msg,
- commitment_msg,
- });
- },
- None => {},
+ if let Some((msg, commitment_msg)) = fulfill_msgs.0 {
+ let mut pending_events = self.pending_events.lock().unwrap();
+ pending_events.push(events::Event::SendFulfillHTLC {
+ node_id: node_id,
+ msg,
+ commitment_msg,
+ });
}
true
},
pending_forward_info.prev_short_channel_id = short_channel_id;
(short_channel_id, chan.update_add_htlc(&msg, pending_forward_info)?)
},
- None => return Err(HandleError{err: "Failed to find corresponding channel", action: None}), //TODO: panic?
+ None => return Err(HandleError{err: "Failed to find corresponding channel", action: None}),
};
match claimable_htlcs_entry {
&mut PendingOutboundHTLC::OutboundRoute { ref route, ref session_priv } => {
(route.clone(), session_priv.clone())
},
- _ => { panic!("WAT") },
+ _ => unreachable!(),
};
*outbound_route = PendingOutboundHTLC::CycledRoute {
source_short_channel_id,
projects / rust-lightning / blobdiff