This commit alters the behavior of the fundingmanager to
rebroadcast the funding transaction of all pending-open
channels upon restart. This is applied only to single-funder
channels for which we are the initiator, and helps ensure that
funding txns do not get stuck in the face of failures or restarts.
In this commit, we fix an existing bug in the funding manager, that can
be triggered if the user is connecting to a node over Tor, and then
attempts to open a channel. An existing fix was added for the case that
the receiving node established the channel, but this now makes that case
symmetric.
This commit changes the failFundingFlow to accept an error, which will
only be sent to the remote the peer if it is among the
ReservationErrors or ErrorCode. This is done to ensure we don't send
errors that contain information we don't want to leak.
This commit adds wallet_best_block_timestamp to the gRPC interface.
This is done in order to allow clients to calculate progress while
lnd syncs to the blockchain. wallet_best_block_timestamp is exposed
via the GetInfo() rpc call. Additionally, IsSynced() returns the
WalletBestBlockTimestamp as the second value in the tuple
that is returned, providing additional detail when querying about the
status of the sync. The BtcWallet interface has also been updated
accordingly.
This commit was created to support the issue to
[Add progress bar for chain sync] (lightninglabs/lightning-app#10) in
lightning-app
This commit makes more channel constraints available
via closures part of the fundingConfig, moving them
from the reservation.RemoteChanConstraints method.
This commit adds the `lnnet` package which contains an
implementation of the newly created LightningNet interface which
multiplexes the Dial and DNS-related functions to use net
by default and torsvc if a flag is specified. This modularization
makes for cleaner code.
In this commit, we fix an existing bug that would result in some
payments getting “stuck”. This would happen if one side restarted
before the channel was fully locked in. In this case, since upon
re-connection, the link will get added to the switch with a *short
channel ID of zero*. If A then tries to make a multi-hop payment
through B, B will fail to forward the payment, as it’ll mistakenly
think that the payment originated from a local-subsystem as the channel
ID is zero. A short channel ID of zero is used to map local payments
back to their caller.
With fix this by allowing the funding manager to dynamically update the
short channel ID of a link after it discovers the short channel ID.
In this commit, we fix a second instance of reported “stuck” payments
by users.
In this commit, we fix an existing bug within the funding manager. A
channel barrier only needs to be create if upon startup the channel is
still pending. Otherwise, we’ll re-create the funding barrier
unnecessarily. This can lead to bugs when initiating payments between a
channels’ lock in and when it’s announced to the together network. If
during this period, a user attempts a payment, then the response won’t
be archived, as the grouting will be blocked waiting on the channel
barrier to close.
To fix this, we only re-create the barrier if the channel hasn’t been
confirmed.
This eliminates one source of reported “stuck payments”.
In this commit, we modify the logic executed when we decide that we
need to fail a funding flow. Before this commit, if the remote party
disconnected while we were attempting to fail the funding flow with an
error. Then we'd never actually cancel the reservation. This meant that
any inputs selected for that transaction would be locked until a
restart.
We fix this issue by always cancelling the reservation first, and
ensuring that failure to cancel the reservation doesn't prevent us from
sending the error.
Partially addresses #710.
Since a ChannelPoint's funding txid can now be get/set as raw bytes or
a string, we first need to check what type it's currently set to before
accessing it.
We no longer need to hand off new channels that come online as the
chainWatcher will be persistent, and always have an active signal for
the entire lifetime of the channel.
This commit defines minRemoteDelay and maxRemoteDelay,
which is the extremes of the CSV delay we will require
the remote to use for its commitment transaction. The
actual delay we will require will be somewhere between
these values, depending on channel size.
This commit makes the fundingmanager read the minHtlc
field of the initFundingMsg, and add it to the reservation
as this node's htlc_minimum_msat for the open_channel
message. If the field is not specified in the initFundingMsg,
the default value found in the DefaultRoutingPolicy will
be used.
This commits slightly rewrites the newly introduced
logic for private channels. Instead of keeping the
channel announce preference in a database within
fundingManager, it is stored as part of the
OpenChannel struct.
In addition, the ChanOpenStatus_Open update is now
sent after the channel is added to the router, instead
of waiting until the 6 blocks confirmation has passed.
This commit introduces some new interdependent functionality. As
soon as the fundingLocked message is sent, the channel is
immediately added to the ChannelRouter's internal topology.
Finally, channels are now only broadcasted to the greater
network after six confirmations on the funding transaction
has been reached.
In this commit, we ensure that we actually advertise our desired value
for the smallest HTLC we’ll accept as incoming. Before this commit, the
value advertised was always zero.
In this commit, we implement a recent spec change that require nodes to
advertise the minHTLC of the remote node within their ChannelUpdate. We
do this as it will be the remote node which carries the HTLC towards
us, therefore we should advertise *their* minHTLC value.
In this commit, we fix an existing issue that could at times cause an
inconsistent view between the set of total coins, and the set of segwit
coins in the wallet of the node. This could be caused by initiating a
funding flow, but then the funding negotiation breaking down somewhere
along the lines. In this case, us or the other peer will disconnect.
When we initiate funding flows, we lock coins exclusively, to ensure
that concurrent funding flows don’t end up double spending the same
coin. Before this commit, we wouldn’t ever unlock those coins. As a
result, our view of available coins would be skewed.
The walletbalance call would show all the coins, but when adding the
—witness_only flag, some coins would be missing, or gone all together.
This is because the former call actually scans the txstore and manually
tallies the amount of available coins, while the latter looks at the
sent of available outputs, which is filtered based on which coins are
locked.
To remedy this, we now ensure that when a peer disconnects, we wipe all
existing reservations which will return any locked outputs to the set
of available outputs for funding flows.
There is a sleep after channels are opened to ensure the channel is
removed from the set of pending reservations. We can avoid this sleep
and get better guarantees of the channel being opened by deleting the
reservation just before updating channel state to active instead of
after.
This commit decouples the wait for funding transaction confirmations
in the waitForFundingConfirmation function from the announcement of
the channel in the sendFundingLockedAndAnnounceChannel function.
Additionally, the sendFundingLockedAndAnnounceChannel function is
now decoupled into the sendFundingLocked and sendChannelAnnouncement
functions. There is also now a helper function that houses creation
of a lnwire.LightningChannel object, calls to both sendFundingLocked
and sendChannelAnnouncement.
This commit adds a select statement for sending on the fundingManager's
arbiterChan and the peer's newChannels channel. This makes sure we won't
be blocked sending on these channels in case of a shutdown.
The fundingManager will register with the server to get notified
when the targetted peer comes online, in case of a failed send
of the fundingLocked message. This is necessary because if the
peer is not connected yet (or was disconnected while we were
waiting for the funding tx to confirm), we cannot continue the
the opening process before the peer successfully has received
the fundingLocked.
This commit adds a channel barrier on fundingManager startup for
channels where the opening process is not finished. This fixes
a bug where we after restarting the fundingManager would receive
the fundingLocked message, and crash when trying to close the
non-existing barrier.
In case we received a fundingLocked message after our own opening
process was finished, we would crash with the same error. We
therefore check if the channel barrier exists before we try to
close it.
It also adds functionality to fundingManager that makes it
ignore a fundingLocked message it receives for a channel where
this is already received. This is necessary when we in case of
a reconnection resend the fundingLocked since we cannot be sure
the remote has received it.
The fundingmanager tests are also updated to check that the
fundingLocked messages are sent and handled correcly, and also
exercise the scanarios described above.
This commit adds a conditional send on quit to all methods used by
outside sub-systems to the funding manager. This ensures, that in the
case the funding manager is exiting, the caller won’t block
indefinitely.
This commit corrects a minor formatting error when logging the pending
channel ID within the logs. Previously, the logging directives and
parameter could cause the pending chan ID to display in a double-hex
encoded format. We fix this by ensuring that we properly slice the chan
ID before printing it, and also ensure that we use the %x formatting
(which will hex encode the bytes) everywhere.
Fixes#331.
This commit implements some missing functionality as we’ll now properly
validate and generate the various channel flow control constraints
during initial channel funding.
With this commit, we take an additional step towards full spec
compliance as we’ll now properly send over the required channel
reservation, max HTLC’s, and other parameters during the funding flow.
When processing the desired parameters by the remote party, if we think
they’re unreasonable, then we’ll send an Error message and end the
funding flow.
Previously, our old lnwire.Error message used a special code to
indicate different types of errors. With the recent push for spec
compatibility, we removed this field and instead stuffed the error into
the first byte of the error data. This works between lnd nodes, but
with other implementations they may send different errors which use a
different error scheme.
To fix this, we’ll now unconditionally return the error to the end
caller (if one exists).
This commit fixes a prior goroutine leak that could result in a node
having thousands of goroutines, particularly due to many concurrent
channel fundings. We now ensure that for each BlockEpoch client
created, we ensure that the client is cancelled once the creating
grouting exits.
This commit updates the tail end of the funding workflow to properly
include the ChainHash field when crafting ChannelAnnouncements and the
initial ChannelUpdate messages. Additionally, we now properly generate
the proper signatures to match the changes to BOLT0007.
This commit modifies the generation and parsing of errors to abandon
usage of the Code field, and instead use the first byte of the Data
field to store the error codes that we currently use. With this change,
we ensure that our error messages properly match BOLT-0002.
Persists the state of a channel opening process after funding
transaction is confirmed. This tracks the messages sent to
the peer such that the process can be continued in case of a
restart. Also introduces that the receiver side forgets about
channel if funding transaction is not confirmed in 48hrs.
Make the fundingmanager send an updated node announcement
each time it opens a new channel. This is to make sure
our node announcement is propagated in the network, since
peers will ignore our node announcements if we haven't
opened any channels yet.
This commit ensures that we always clean up the resources that are
created when a new instance of a lnwallet.LightningChannel is
instantiated. The is necessary due to the sigPool that’s now present as
an internal goroutine.
This commit updates the main single-funder funding workflow within the
fundingManager (initiated via the rpcserver or by a message from a
connected peer) to fully adhere to the funding protocol outlined in
BOLT-0002.
The major changes are as follows:
* All messages modified to use the new funding messages in BOLT-0002.
* The initiator of a funding workflow no longer decides how many
confirmations must elapse before the channel can be considered open.
* Rather than each side specifying their desired CSV delay, both
sides now specify the CSV delay for the _other_ party.
This commit fixes a possible panic within the funding manger’s workflow
for pending channels. We now ensure that the local discovery signal
retrieved from the localDiscoverySignals map is always non-nil.
Otherwise, we risk a server panic in the case that a node retransmits
the FundingLocked message after a channel has been fully processed, or
even just sends a FundingLocked message for a non-existent channel.
This commit adds a new bit of synchronization to the funding manager to
ensure that we only process the funding locked message directly _after_
the short channel ID has become available within the channel. This
fixes a possible bug wherein we would receive the funding locked
message, and register the channel with the switch without yet knowing
the short chan ID. This would then cause any HTLC’s routed to the new
channel to fail, as it would be using the incorrect short channel ID.
This commit modifies the funding process to use the short channel ID,
rather than only the opening block height to mark a channel as open
once it has been confirmed. With this change, the short channel ID
information will now be available immediately after the channel has
been confirmed in the chain.
This commit modifies the funding workflow slightly to move the querying
to the fee estimator (for the new channel) into the fundingManager
rather than within the LightningWallet layer. When querying to
FeePerWeight, we now multiply by 1000 to arrive at fee-per-kw.
Additionally, we now also properly thread through the fee-per-kw
offered by the initiator the to the responder of the channel workflow.
This commit adds the FeeEstimator interface, which can be used for
future fee calculation implementations. Currently, there is only the
StaticFeeEstimator implementation, which returns the same fee rate for
any transaction.
In order to make the node's dust limit available to the wallet during
the initial stages of the funding process, add and set a
DustLimit field in the Contribution.
This commit modifies the OpenChannel structure on-disk to also track
that opening height of a channel. This change is being made in order to
make and more light client friendly. A follow up commit will modify
several areas of the codebase to use this new functionality.
This commit fixes a bug that double counts the number of pending
channels in GetInfo. Previously we weren’t yet storing the pending
channels on disk, we are now but comparing both the disk channel and
the channels within memory leads us to double count channels. To fix
this, we now only count the database channels.
Note that this NumPendingChannels method can now be removed as it’s no
longer needed.
This commit modifies the order of operations after a channel has been
detected as fully opened. Rather than waiting until we receive the
FundingLocked message to announce the channel, we now do so immediately
after we detect the channel has been opened.
Additionally, we also patch a possible dead-lock bug by ensuring that
the RevokeAndAck message is always sent _after_ the FundingLocked
message. We do this by only passing the newly created channel too the
relevant sub-systems _after_ we receive the FundingLocked message. This
movement also serves to pave the way for our switch to the spec’s
funding workflow, as once we remove the initial revocation window,
there’ll be no way for us to initiate a state transition until we
receive the FundingLocked message from the remote party.
This commit modifies the way the fundingManager tracks pending funding
workflows internally. Rather than using the old auto-incrementing
64-bit pending channel ID’s, we now use a 32-byte pending channel ID
which is generated using a CSPRG. Additionally, once the final funding
message has been sent, we now de-multiplex the FundingLocked message
according to the new Channel ID’s which replace the old ChannelPoint’s
and are exactly 32-bytes long.
This commit modifies the fundingManager config to use the a SignMesage
function rather than two distinct functions for singing one half the
channel announcement proofs. This change unifies the signing of
messages under a single abstraction: the MessageSigner interface.
This commit implements some minor coding style, commenting and naming
clean up after the recent major discovery service was merged into the
codebase.
Highlights of the naming changes:
* fundingManager.SendToDiscovery -> SendAnnouncement
* discovery.Discovery -> discovery.AuthenticatedGossiper
The rest of the changes consist primary of grammar fixes and proper
column wrapping.
Change the name of fields of messages which are belong to the discovery
subsystem in a such way so they were the same with the names that are
defined in the specification.
Add usage of the 'discovery' package in the lnd, now discovery service
will be handle all lnwire announcement messages and send them to the
remote party.
This commit modifies the path finding routines to properly use the new
channel edge related API exposed by the database. Additionally, a new
type `ChannelHop` has been introduced which couples an edges routing
policy with the capacity and origin chain of the channel.
This commit fixes a bug that resulted from properly failing to do a
2-value read from the confirmation notification channel. If the
ChainNotifier was shutting down, then a nil read could be generated
which may prematurely mark the channel as open, and also trigger a nil
pointer panic exception below when the confDetails are accessed.
We fix this issue, by ensuring that we check the second value to see if
the channel has been closed or not.
This commit renames routing processing method in the funding mangers
config from ProcessRoutingMessage to SendToRouter and also modifies the
signature to only require the message itself and not the server’s
identity public key.
When the funding transaction has been confirmed, the FundingLocked
message is sent by the peers to each other so that the existence of the
newly funded channel can be announced to the network.
This commit also removes the SingleFundingOpenProof message.
Once a channel funding process has advanced to the point of broadcasting
the funding transaction, the state of the channel should be persisted
so that the nodes can disconnect or go down without having to wait for the
funding transaction to be confirmed on the blockchain.
Previously, the finalization of the funding process was handled by a
combination of the funding manager, the peer and the wallet, but if
the remote peer is no longer online or no longer connected, this flow
will no longer work. This commit moves all funding steps following
the transaction broadcast into the funding manager, which is available
as long as the daemon is running.
In order to facilitate persistence during the funding process, added
the isPending flag to channels so that when the daemon restarts, we can
properly re-initialize the chain notifier and update the state of
channels that were going through the funding process.
github.com/lightningnetwork/lnd master ✗
0m ◒
▶ golint
htlcswitch.go:292:4: should replace numUpdates += 1 with numUpdates++
htlcswitch.go:554:6: var onionId should be onionID
htlcswitch.go:629:7: var onionId should be onionID
lnd_test.go:133:1: context.Context should be the first parameter of a
function
lnd_test.go:177:1: context.Context should be the first parameter of a
function
networktest.go:84:2: struct field nodeId should be nodeID
peer.go:1704:16: should omit 2nd value from range; this loop is
equivalent to `for invoice := range ...`
rpcserver.go:57:6: func newRpcServer should be newRPCServer
github.com/lightningnetwork/lnd master ✗
9m ⚑ ◒ ⍉
▶ go vet
features.go:12: github.com/lightningnetwork/lnd/lnwire.Feature
composite literal uses unkeyed fields
fundingmanager.go:380: no formatting directive in Errorf call
exit status 1
Previously, during the channel funding process, peers sent wire
messages using peer.queueMsg. By switching to server.sendToPeer, the
fundingManager is more resilient to network connection issues or system
restarts during the funding process. With server.sendToPeer, if a peer
gets disconnected, the daemon can attempt to reconnect and continue the
process using the peer’s public key ID.
This commit adds a new restriction around funding channels at the
daemon level: lnd nodes will not allow either the initiation or the
acceptance of a channel before the node is fully synced to the best
known chain.
This fixes a class of bug that arises when a new node joins the network
and either attempts to open a channel or has a channel extended to them
before the node is fully synced to the network.
This commit ensures that we now properly handle and propagate errors
that arise when attempting to create a new channel after the funding
transaction is believed to be confirmed.
A previous edge case would arise when a user attempted to create a new
channel, but their corresponding btcd node wasn’t yet fully synced.
This commit modifies the login of sent/recv’d wire messages in trace
mode in order utilize the more detailed, and automatically generated
logging statements using pure spew.Sdump.
In order to avoid the spammy messages due to spew printing the
btcec.S256() curve paramter within wire messages with public keys, we
introduce a new logging function to unset the curve paramter to it
isn’t printed in its entirety. To insure we don’t run into any panics
as a result of a nil pointer defense, we now copy the public keys
during the funding process so we don’t run into a panic due to
modifying a pointer to the same object.
This commit adds daemon level support for pushing funds as part of the
single funder channel workflow. This new feature allows the user to
open a channel and simultaneously make a channel at the same time which
can improve the UX when setting up a channel for the first time.
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 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 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 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.
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 finalizes the implementation of #58 by integrating passing
around the obfuscate state hints into the funding workflow of the
wallet, and also the daemon’s funding manager.
In order to amend the tests, the functions to set and receive the state
hints are now publicly exported.
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 modifies the existing channel reservation workflow slightly
to thread through the IP address that we were able to reach the node
at, or the one which the node reached us via. Additionally, rather than
using OpenChannel.FullSync() at the end of the reservation workflow, we
now use OpenChannel.FullSyncWithAddr() in order to create the
relationship in the database between the channel, and the p2p node we
created the channel with.
All tests, as well as a portion of the fundingManager have been updated
accordingly,
This commit adds a new RPC command: `channelbalance` which returns the
sum of all available channel capacity across all open channels. The
total balance is currently returned in units of `satoshis`. Additionally
the `networkHarness` has been modified slightly to allow specifying the
additional "extra" command line parameters when creating the initial
seed nodes. Minor refactoring within the integration tests has been
undertaken in order to increase code re-use across tests.
Closes#29.
This commit modifies the prior funding workflow to account for fees
when creating the funding output. As a stop gap, the current fee for
the commitment transaction is now hard-coded at 5k satoshis. Once the
fee models are in place this should instead be some high multiple of
the current “average” fee rate within the network, continuing, the
proper fee should be adjusted from the commitment transaction has
outputs are added/removed.
LIGHT-131, LIGHT-140, LIGHT-138
`lncli showroutingtable` may output routing table as image.
Use graphviz for graph rendering.
Add explicit version dependency for tools. Add error checking.
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 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 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 adds a ticker which attempts to print the total volume
sent/recv over the last 10 seconds if any updates took place during
that interval.
Additionally, when selecting a link to forward an htlcPacket insert a
break after selection in order to properly terminate the loop.
With this commit, support for changing the target network (testnet,
simnet, etc) has been finalized. Previously a command line option was
present to swap networks, but the RPC port wouldn’t automatically be
updated to reflect the network.
This commit implements the “pendingchannels” RPC within the rpcserver.
This RPC allows callers to receive details concerning the current
pending channels associated with the daemon. Pending channels are those
waiting for additional confirmations before they can be considered
opened/closed.
At the time of this commit, only open channels are shown. A future
commit will also add the confirmation updates, along with information
for close channels.
This commit adds the necessary plumbing within the server, peer, and
rpcServer to handle opening and cooperatively closing a channel with a
remote peer.
Many new data structures have been added to the peer in order to allow
it to efficiently manage opening+.losing new/existing lightning
channels. Additional documentation has been added to several methods
within the peer struct, with some minor renaming along with way. The
peer has also gained a dedicated goroutine whose job it is to manage
any requests pertaining to opening, or closing any channels with the
remote peer.
The messages have been added to lnrpc define the requests and responses
to channel open+close messages. Additional channel logic has been added
between the rpcServer, peer, and server in order to properly manage the
necessary synchronization.
This commit introduces the fundingManger which is used as a bridge
between the wallet’s internal ‘ChannelReservation’ workflow, and the
wire protocol’s funding messages.
The funding manger is responsible for progressing the workflow, and
communicating any errors generated during the workflow back to the
source peer.
