This commit adds a critical capability to the daemon: proper handling
of error cases that occur during the dispatch and forwarding of
multi-hop payments.
The following errors are now properly handled within the daemon:
* unknown payment hash
* unknown destination
* incorrect HTLC amount
* insufficient link capacity
In response to any of these errors, an lnwire.CanceHTLC message will be
back propagated from the spot of the error back to the source of the
payment. In the case of a locally initiated HTLC payment, the error
will be propagated back to the client which initiated the payment.
At this point, proper encrypted error replies as defined within the
spec are not yet implemented and will be fully implemented within a
follow up PR.
This commit makes a large number of minor changes concerning API usage
within the deamon to match the latest version on the upstream btcsuite
libraries.
The major changes are the switch from wire.ShaHash to chainhash.Hash,
and that wire.NewMsgTx() now takes a paramter indicating the version of
the transaction to be created.
This commit adds a much needed feature to the daemon, namely the
ability to force close a channel while the source daemon doesn’t have
an active connection to the counter party. Previously this wasn’t
possible as ALL channel closures were routed through the htlcSwitch
which is only able to trigger a channel closure if the peer is online.
To remedy this, if the closure type is “force” then, we now handle the
channel closure and related RPC streaming updates from the call handler
site of the RPC itself. As a result, there are now only two htlcSwitch
channel closure types: breach, and regular. The logic that’s now in the
rpcSever should likely be refactored into a distinct sub-system, but
getting the initial functionality in is important.
Finally, the channel breach integration test has been modified to skip
connection the peers before attempting the forceful channel closure of
a revoked state as the remote peer no longer needs to be online.
This commit modifies the interaction between the breachArbiter and the
peer struct such that the breachArbiter _always_ has the latest version
of a contract.
Prior to this commit once we connected out to a peer which we had an
active contract with and the breachArbiter was watching, we’d have two
copies of the channel in memory, instead of just a single one. This was
wasteful and caused some duplicated log messages due to two instances
of the channel being active.
This commit fully integrates the ChannelRouter of the new routing
package into the main lnd daemon.
A number of changes have been made to properly support the new
authenticated gossiping scheme.
Two new messages have been added to the server which allow outside
services to: send a message to all peers possible excluding one, and
send a series of messages to a single peer. These two new capabilities
are used by the ChannelRouter to gossip new accepted announcements and
also to synchronize graph state with a new peer on initial connect.
The switch no longer needs a pointer to the routing state machine as it
no longer needs to report when channels closed since the channel
closures will be detected by the ChannelRouter during graph pruning
when a new block comes in.
Finally, the funding manager now crafts the proper authenticated
announcement to send to the ChannelRouter once a new channel has bene
fully confirmed. As a place holder we have fake signatures everywhere
since we don’t properly store the funding keys and haven’t yet adapted
the Signer interface (or create a new one) that abstracts out the
process of signing a generic interface.
This commit adds some additional measures to ensure that a call to
queueMsg while the peer is shutting down won’t result in a potential
deadlock.
Currently, during shutdown the outgoingQueue channel is attempted to be
cleared by he writeHandler, however adding an additional select
statement serves as a mother layer of defense from nasty dead locks.
This commit revamps the way in bound and outbound connections are
handled within lnd. Instead of manually managing listening goroutines
and also outbound connections, all the duty is now assigned to the
connmgr, a new btcsuite package.
The connmgr now handles accepting inbound (brontide) connections and
communicates with the server to hand off new connections via a
callback. Additionally, any outbound connection attempt is now made
persistent by default, with the assumption that (for right now),
connections are only to be made to peers we wish to make connections
to. Finally, on start-up we now attempt to connection to all/any of our
direct channel counter parties in order to promote the availability of
our channels to the daemon itself and any RPC users.
This commit fixes a htlcSwitch bandwidth update bug that would manifest
when two sending daemons were started with the —debughtlc flag. The
invoice created for the debug HTLC has a value of 1000BTC. As a result
regardless of the amount sent, the switch’s state which be updated to
reflect that the daemon had just received a 1000BTC transfer.
To fix this bug, we now use the value of the HTLC itself for the
update, rather than the value if the invoice as they should match.
This commit introduces a new sub-system into the daemon whose job it is
to vigilantly watch for any potential channel breaches throughout the
up-time of the daemon. The logic which was moved from the utxoNursery
in a prior commit now resides within the breachArbiter.
Upon start-up the breachArbiter will query the database for all active
channels, launching a goroutine for each channel in order to be able to
take action if a channel breach is detected. The breachArbiter is also
responsible for notifying the htlcSwitch about channel breaches in
order to black-list the breached linked during any multi-hop forwarding
decisions.
This commit removes the previously added contract breach retribution
duties from the utxoNursery. Much of the code removed will instead be
moved to a new sub-system which continuously monitors the state of ALL
active contracts for their entire life time.
Use [33]byte for graph vertex representation.
Delete unneeded stuff:
1. DeepEqual for graph comparison
2. EdgePath
3. 2-thread BFS
4. Table transfer messages and neighborhood radius
5. Beacons
Refactor:
1. Change ID to Vertex
2. Test use table driven approach
3. Add comments
4. Make graph internal representation private
5. Use wire.OutPoint as EdgeId
6. Decouple routing messages from routing implementation
7. Delete Async methods
8. Delete unneeded channels and priority buffer from manager
9. Delete unneeded interfaces in internal graph realisation
10. Renamed ID to Vertex
This commit adds the necessary logic a peer’s htlcManger goroutine to
dispatch justice (sweeping all the funds in a channel) after it has
been detected that the counter-party has broadcast a prior revoked
commitment state.
The task to generate the justice transaction is handed off to the
utxoNursery. Once the nursery has finished its duty, the peer launches
a new goroutine which will delete the state of the channel once the
justice transaction has been confirmed within a block.
This commit refactors the peer struct slightly in order to implement
the new ping/pong workflow added in a prior commit. Pings are currently
sent every 30 seconds unconditionally.
This commit modifies both the Sphinx packet generation and processing
for recent updates to the API.
With the version 1 Sphinx specification, the payment hash is now
included in the MACs in order to thwart any potential replay attacks.
As a result, any attempts to replay previous HTLC packets MUST re-use
the same payment hash, meaning that the first-hop node can simply
settle the HTLC immediately, thwarting the attacker.
Additionally, within the Sphinx packet, each hop now gets a per-hop
payload which contains the necessary details (CTLV value, fee, etc) for
the node to successfully forward the payment. This per-hop payload is
protected by a packet-wide MAC.
This commit modifies the existing p2p connection authentication and
encryption scheme to now use the newly designed ‘brontide’
authenticated key agreement scheme for all connections.
Additionally, within the daemon lnwire.NetAddress is now used within
all peers which encapsulates host information, a node’s identity public
key relevant services, and supported bitcoin nets.
This commit takes advantage of the newly added
channeldb.FetchAllChannels method to return the state of all active
channels for the ListChannels RPC command. With this change the state
of all channels can now be queried regardless of if any/all the peers
are currently online.
In a future modification a bit will be added to the channel information
which indicates if the LinkNode the channel was created with is
currently online or not.
This commit fixes a bug which was introduced when the routing table was
switched over to store full pub keys rather then public key hashes. The
switch was change was required in order to properly support onion
routing within the daemon. During the change the source node vertex
when receiving a message wasn’t converted to use public keys instead of
pubkeyhashes. As a result, nodes would be blind to any topology related
updates sent by its neighbors.
This commit fixes the bug by setting the source node of the received
message to the serialized public key rather than the pubkeyhash.
This commit consists of a mass variable renaming to call the pkScript being executed for segwit outputs the `witnessScript` instead of `redeemScript`. The latter naming convention is generally considered to be reserved for the context of BIP 16 execution. With segwit to be deployed soon, we should be using the correct terminology uniformly through the codebase.
In addition some minor typos throughout the codebase has been fixed.
This commit adds a few workarounds in order to concurrently support the
REST proxy as well as the regular gRPC interface. Additionally,
concrete support for the following RPC calls has been added:
GetTransactions, SubscriptTransactions, SubscribeInvoices, and
NewWitnessAddress.
This commit adds an additional clause to the update of the current
commitment state each time the commitTimer ticks. We now additional
check to see if we have any active HTLC’s to settle, triggering a state
update if so.
This case is needed due to the possibility of desynchronization across
commitment transactions. As an example if any HTLC adds are sent after
the remote node receives our ack-sig, then they may remain uncommitted
within our local commitment chain. The addition of this check solves
the issue by ensuring convergence towards a symmetric commitment state.
This commit properly removes any/all closed channels from the routing
table. In the current implementation individual links (channels)
between nodes are treated sparely from the PoV of the routing table. In
the future, this behavior should be modified such that, the routing
table views all the links between nodes as a single channel. Such a
change will simplify the task of path finding as the links can simply
be viewed as a channel with the sum of their capacities. The link layer
(htlcSwitch) will handle the details of fragmentation on a local basis.
This commit adds full support for multi-hop onion routed payments
within the daemon.
The switch has been greatly extended in order to gain the functionality
required to manage Sphinx payment circuits amongst active links. A
payment circuit is initiated when a link sends an HTLC add to the
downstream htlcSwitch it received from the upstream peer. The switch
then examines the parsed sphinx packet to set up the clear/settle ends
of the circuit. Created circuits can be re-used amongst HTLC payments
which share the same RHash.
All bandwidth updates within a link’s internal state are now managed
with atomic increments/decrements in order to avoid race conditions
amongst the two goroutines the switch currently uses.
Each channel’s htlcManager has also been extended to parse out the
next-hop contained within Sphinx packets, and construct a proper
htlcPkt such that the htlcSwitch can initiate then manage the payment
circuit.
This commit alters the send/receive HTLC pipe line a bit in order to
fully integrate onion routing into the daemon.
The server now stores the global Sphinx router which all active
htlcManagers will used when processing upstream HTLC add messages.
Currently the onion routing private key is static, and identical to the
node’s current identity public key. In the future this key will be
rotated daily the node based on the current block hash.
When sending a payment via the SendPayment RPC, the routing manager is
now queried for the existence of a route before the payment request is
sent to the HTLC switch. If a path is found, then a Sphinx onion packet
encoding the route is created, then populated within the HTLC add
message.
Finally, when processing an upstream HTLC add request, the sphinx
packet is decoded, then processed by the target peer. If the peer is
indicated as the exit node, then the HTLC is queue’d to be settled
within the next state update.
This commit extends the existing invoiceRegistry functionality to wrap
the on-disk invoices available via the channeldb with an in-memory
cache on invoices. Currently the in-memory cache is only reserved for
the storage of special “debug” invoices which all nodes are able to
settle immediately.
This commit includes some slight refactoring to properly execute force
closures which are initiated by RPC clients.
The CloseLink method within the htlcSwitch has been extended to take an
additional parameter which indicates if the link should be closed
forcefully. If so, then the channelManager which dispatches the request
executes a force closure using the target channel state machine. Once
the closing transaction has been broadcast, the summary is sent to the
utxoNursery so the outputs can be swept once they’re mature.
This commit introduces the concept of a manually initiated “force”
closer within the channel state machine. A force closure is a closure
initiated by a local subsystem which broadcasts the current commitment
state directly on-chain rather than attempting to cooperatively
negotiate a closure with the remote party.
A force closure returns a ForceCloseSummary which includes all the
details required for claiming all rightfully owned outputs within the
broadcast commitment transaction.
Additionally two new publicly exported channels are introduced, one
which is closed due a locally initiated force closure, and the other
which is closed once we detect that the remote party has executed a
unilateral closure by broadcasting their version of the commitment
transaction.
LIGHT-138, LIGHT-141. Due to some issues in sending/receiving parts of lnd,
messages with zero length are not sent. So added some mock content to
NeighborAck. Moved sender/receiver from routing message to wrap message
which contains lnwire routing message.
This commit modifies the daemon’s initialization within the `lndMain`
method to create an instance of the current default ChainNotifier
outside of the LightningWallet.
At this point, since there are no other implementations of the
ChainNotifier, the current concrete implementation BtcdNotifier is used
by default. In the future, once other ChainNotifier implementations are
in place, config parsing should be fed into a factory function which
creates the proper ChainNotifier implementation.
Finally, several imports have been updated to reflect the change in
package name.
This commit modifies the internal workflow for opening or closing a
channel in order to create a path in which RPC clients can receive
updates. Updates are now communicated via channels from the goroutines
spawned by the RPC server to process the request, and the sub-system
within the daemon that actually executes the request.
With this change clients can now receive updates that the request is
pending (final message has been sent to the target client), or that the
request has been completed. Confirmation related updates have not yet
been implemented as that will require some changes to the ChainNotifier
interface.
This commit fixes an omission within the htlcSwitch. With this commit,
a channels bandwidth is now properly updated once an incoming HTLC is
settled.
This also fixes a bug where if a node received a payment, it wouldn’t
be able to then utilize the newly available bandwidth to send further
payments.
This commit integrates BitFury's current routing functionality into lnd. The
primary ochestration point for the routing sub-system in the routingMgr. The
routingMgr manages all persistent and volatile state related to routing within
the network.
Newly opened channels, either when the initiator or responder are inserted into
the routing table once the channel is fully open. Once new links are inserted
the routingMgr can then perform path selection in order to locate an "optimal"
path to a target destination.
This commit optimizes the previous deadlock bug-fix within the peer’s
channelManager which handles driving the LCP state machine with
additional context-specific state.
Rather than forwarding to the HTLC switch within the primary loop which
handles fully locked-in HTLCs, we now launch a distinct goroutine which
is responsible for properly forwarding lock-in HTLC’s to the
htlcSwitch.
