In this commit, we modify the way we attempt to locate the our channel
peer to establish a persistent connection on start up. Before this
commit, we would use the channel policy pointing to the peer to locate
the node as it's embedded in the struct. However, at times it's
currently possible for the channel policy to not be found in the
database if the remote nodes announces before we finalize the process on
our end. This can at times lead to a panic as the pointer isn't checked
before attempting to access it.
To remedy this, we now instead use the channel info which will _always_
be there if the channel is known.
In this commit, we modify the decoding of the FailUnknownPaymentHash
message to ensure we're able to fully decode the legacy serialization of
the onion error. We do this by catching the `io.EOF` error as it's
returned when _no_ bytes are read. If this is the case, then only the
error type was serialized and not also the optional amount.
In this commit, we fix a bug in the way we defined our even/odd features
for a particular feature. The check for if a feature bit is part of a
pair assumes that the pair bit has the exact same name as the bit being
queried. The way we defined our feature map didn't take note of this
assumption, as a result, any attempts to require a new bit moving from
optional to required would fail since the bit would be found, but the
names differed.
This reverts commit 4aa52d267f.
It turns out that the other implementations set values for this field
which aren't based on the actual capacity of the channel. As a result,
we'll no reject most of their channel offerings, since they may offer a
value of a max `uint64` or something else hard coded that's above the
size of the channel. As a result, we're reverting this check for now to
maintain proper compatibility.
In this commit, we modify areas where we need to force close a channel
to use the new FetchChannel method instead of manually scanning. This
dramatically reduces the CPU usage when doing things like closing a
large number of channels within lnd.
In this commit, we remove an extra openChannel.FullSync() call from
breacharbiter_test.go. Before this collective diff, calling
SyncPending() then FullSync() didn't result in an error. However, a
prior commit now makes this an error to ensure we don't attempt to
override any existing channels. This is the only area in the codebase
that we made this mistake which in this case, was benign.
In this commit, we ensure that if a channel is detected to have local
data loss, then we don't allow a force close attempt, as this may not be
possible, or cause us to play an invalid state.
In this commit, we add a new type (ChannelShell) along with a new
method, RestoreChannelShells which allows a caller to insert a series of
channel shells into the database. These channel shells will allow a
restored node to initiate the DLP protocol and recover their set of
existing channels.
When we insert a channel shell, we re-create the original link node, and
also add the outgoing edge to the channel graph. This way we can be sure
that upon start up, we attempt to connect to the remote peers, and that
the normal graph query commands will operate as expected.
If the ChanStatusRestored flag is set, then we don't need to write or
read the set of commits for a channel as they won't exist. This will be
the case when we restore a channel from an SCB.
The new syncNewChannel function will allow callers to insert a new
channel given the OpenChannel struct, and set of addresses for the
channel peer. This new method will also create a new LinkNode for the
peer if one doesn't already exist.
In this commit, we modify the String() method of the ChannelStatus type
to reflect the fact that it's a flag set. With these new changes, we'll
now print the variable name of each assigned bit with a bar delimiting
them all.
In this commit, we add a prefix naming scheme to the ChannelStatus enum
variables. We do this as it enables outside callers to more easily
identify each individual enum variable as a part of the greater
enum-like type.
In this commit, we add a new AddrsForNode method. This method will allow
a wrapper sturct to implement the new chanbackup.LiveChannelSource
method which is required to implement the full SCB feature set.
In this commit, we increase the default trickle delay from 30s to 1m30s.
We do this as before we implement the new INV gossip mechanism, we want
to de-emphasise the quick propagation of updates through the network
which eats up bandwidth.
In this commit, we introduce the chanbackup.SubSwapper interface. It
takes a regular Swapper implementation (defined by the
chanbackup.SubSwapper) interface along with a chanbackup.ChannelNotifier
implementation. Given these two interfaces, we're able to be notified
when a new channel is opened or closed, and then use the Swapper to
atomically replace the on-disk channel back up. As a result, a Lightning
daemon can ensure that they alwayts have a up to date channels.backup on
disk that can safely be copied away by users and be used to restore
channel funds in the event of partial/total data loss.
In this commit, we add a new MultiFile struct. We'll use this struct in
store the latest multi-channel backup on disk, swap it out atomically,
and finally extract+unpack the contents of the multi-file. The format
that's written to disk is the same as a regular Packed multi. The
contents of this new file are meant to be used to safely implement an
always up to date multi file on disk as a way for users to easily rsync
or fsnotiy (when it changes) the backup state of their channels.
We implement an atomic update and swap in the UpdateAndSwap. The method
uses relies on the underlying file system supporting an atomic rename
syscall. We first make a temporary backup file, write the latest
contents to that, then swap the temp file with the main file using
rename(2). This way, we ensure that we always have a single up to date
file, if the protocol aborts before the rename, then we can detect this,
remove the temp file, and attempt another swap.
In this commit, we add a series of functions that will allow users to
recover existing channel backups. We do this using two primary
interfaces: the ChannelRestorer, and the PeerConnector. The first
interfaces allows us to abstract away the details w.r.t exactly how a
channel is restored. Instead, we simply expect that the channel backup
will be inserted as a sort of "channel shell" which contains only the
data required to initiate the data loss protection protocol. The second
interface is how we instruct the Lightning node to connect out to the
channel peer given its known addresses.
In this commit, we introduce a series of interfaces and methods that
will allow external callers to backup either all channels, or a specific
channel identified by its channel point. In order to abstract away the
details w.r.t _how_ we obtain the set of open channels, or their storage
mechanisms, we introduce a new LiveChannelSource interfaces. This
interfaces allows us to fetch all channels, a channel by its channel
point, and also all the known addresses for a node as we'll need this in
order to connect out to the node in the case of a recovery attempt.
In this commit, we introduce the Multi sturct. Multi is a series of
static channel backups. This type of backup can contains ALL the channel
backup state in a single packed blob. This is suitable for storing on
your file system, cloud storage, etc. Systems will be in place within
lnd to ensure that one can easily obtain the latest version of the Multi
for the node, and also that it will be kept up to date if channel state
changes.
In this commit, we add the initial implementation of the SCB structure.
Given an SCB, and a user's seed, it will be possible to recover the
settled balanced of a channel in the event of total or partial data
loss. The SCB contains all information required to initiate the data
loss protection protocol once we restore the channel and connect to the
remote channel peer.
The primary way outside callers will interact with this package are via
the Pack and Unpack methods. Packing means writing a
serialized+encrypted version of the SCB to an io.Writer. Unpacking does
the opposite.
The encoding format itself uses the same encoding as we do on the wire
within Lightning. Each encoded backup begins with a version so we can
easily add or modify the serialization format in the future, if new
channel types appear, or we need to add/remove fields.
In this commit, we implement a series of new crypto operations that will
allow us to encrypt and decrypt a set of serialized channel backups.
Their various backups may have distinct encodings when serialized, but
to the functions defined in this file, we treat them as simple opaque
blobs.
For encryption, we utilize chacha20poly1305 with a random 24 byte nonce.
We use a larger nonce size as this can be safely generated via a CSPRNG
without fear of frequency collisions between nonces generated. To
encrypt a blob, we then use this nonce as the AD (associated data) and
prepend the nonce to the front of the ciphertext package.
For key generation, in order to ensure the user only needs their
passphrase and the backup file, we utilize the existing keychain to
derive a private key. In order to ensure that at we don't force any
hardware signer to be aware of our crypto operations, we instead opt to
utilize a public key that will be hashed to derive our private key. The
assumption here is that this key will only be exposed to this software,
and never derived as a public facing address.
In this commit, we update the release script to include a directory
containing all of our vendored dependencies. This makes out releases
more self contained as they can be built using `go build -mod=vendor`
without requiring any package fetching.
Additionally, we pacakge the entire source as well.
Fixes#1550.
In this commit, we modify our default local feature bits to require the
Data Loss Protection (DLP) feature to be active. Once full Static
Channel Backups are implemented, if we connect to a peer that doesn't
follow the DLP protocol, then the SCBs are useless, as we may not be
able to recover funds. As a result, in prep for full SCB deployment,
we'll now ensure that any peer we connect to, knows of the DLP bit. This
could be a bit more relaxed and allow _connections_ to non-DLP peers,
but reject channel requests to/from them. However, this implementation is
much simpler.
In this commit, we add a new section to the code contribution guidelines
explaining how to use `go mod replace`. This will be a common procedure
for any developer that needs to make a change in any of our sister
projects, so it's nice to have this outlined in a single place.
In this commit we fix a compatibility issue with other implementations.
Before this commit, when writing out an onion error that includes a
`ChannelUpdate` we would use the `MaxPayloadLength` to get the length to
encode. However, a recent update has modified that to be the max
`brontide` payload length as it's possible to pad out the message with
optional fields we're unaware of. As a result, we would always write out
a length of 65KB or so. This didn't effect our parser as we ignore the
length and decode the channel update directly as we don't need the
length to do that. However, other implementations depended on the length
rather than just reading the channel update, meaning that they weren't
able to decode our onion errors that had channel updates.
In this commit we fix that by introducing a new
`writeOnionErrorChanUpdate` which will write out the precise length
instead of using the max payload size.
Fixes#2450.
In this commit, we add a new flag to the sendcoins command that allows
callers to sweep all funds out of the daemon's wallet. This CANNOT be
set at the same time that an amount is specified.
In this commit, we implement the new feature which allows sendcoins to
sweep all the coins in the wallet. We use the new sweep.CraftSweepAllTx
method, and also use WithCoinSelectLock to ensure that we don't trigger
any double-spend errors triggered by coin selection race conditions.
In this commit, we add a new method WithCoinSelectLock. This method will
allow us to fix bugs in the project atm that can arise if a channel
funding is attempted (either manually or by autopilot) while a users is
attempting to send an on-chain transaction. If this happens
concurrently, then both contexts will grab the set of UTXOs and attempt
to lock them one by one. However, since they didn't obtain an exclusive
snapshot of the UTXO set of the wallet, they may both attempt to lock
the same input.
We also ensure that calls to SendMany cannot run into this issue by
using the WithCoinSelectLock synchronization when attempting to instruct
the internal wallet to send payments.
In this commit, we add a new function, CraftSweepAllTx. This function
allows callers to craft a transaction which sweeps ALL outputs from the
wallet to a single target address. It can either be used for UTXO
consolidation (at the cost of privacy by co-mingling inputs), or simply
to sweep all funds out of a wallet for various reasons.
In an attempt to ensure this method is loosely coupled and testable, for
all behavior structs, we create brand new interface to accept. This
ensures that we only rely on the minimal number of methods needed to
perform our duty.
In this commit, we update the `getInputWitnessSizeUpperBound` and all
its callers to be aware of nested p2sh witness inputs. We do so by
adding another bool which is true if the output is a nested p2sh output.
If so, then in order to properly estimate the total weight, the caller
needs to factor in the non-witness data of the additional sigScript data
push.
In this commit, we extend the WitnessGenerator type to now return an
InputScript. This allows it to be more encompassing, as now callers can
expect a sigScript to be populated if the input being swept requires a
sigScript field.
Along the way, we've also renamed input.BuildWitness to
input.CraftInputScript. We also take a step towards allowing the
sweeper to sweep transactions for n2pwkh outputs. We do so by modifying
the BuiltWitness method to instead return an InputScript. Additionally,
when populating inputs if a sigScript is present, it will now be
populated.
Olaoluwa Osuntokun