This commit adds the ability to store closed channels by scid in
the database. This will allow the gossiper to ignore channel
announcements for closed channels without having to do any
expensive validation.
ChanUpdate timestamps are now restircted so that they cannot be
more than two weeks into the future. Moreover channels with both
timestamps in the ReplyChannelRange msg either too far in the past
or too far in the future are not queried.
Moreover fix unitests.
In preparation for adding a clean Graph DB interface, we create a
version of FetchLightningNode that doesnt allow a caller to provide in a
transaction.
With the new postgres concurrency control, an error may come from a
bucket function that's actually a postgres error. In this case, we need
to return early so we can retry the txn. Otherwise, we'll be working
with an aborted tx, and never actually return the error so we don't auto
retry.
In this commit, the FetchChanInfos ChannelGraph method is updated to
take in an optional read transaction for the case where it is called
from within another transaction.
In order to emphasise the fact that the ChannelGraph's cacheMu should be
acquired before calling the `delChannelEdge` method, we add the `Unsafe`
postfix and add a comment to alert readers.
In this commit, we ensure that the channeldb cacheMu mutex is only ever
aquired _before_ acquiring the main DB lock in the cases where the two
locks need to be held simultaneously.
With this commit, the deadlock demonstrated in the previous commit is
now fixed.
This commit is a set-up commit. It extracts the logic from
`MarkEdgeLive` to a helper `markEdgeLive` method so that the logic can
be called from within other kvdb.Update blocks. This will be used in the
next commit.
Let MarkEdgLive return a new ErrNotZombieEdge error if an entry with the
given channel ID cannot be found. In processZombieUpdate, we then
check for this error and log accordingly.
Finally, The LightningNode object is removed from ChannelEdgePolicy.
This is a step towards letting ChannelEdgePolicy reflect exactly the
schema that is on disk.
This is also nice because the `Node` object is not necessarily always
required when the ChannelEdgePolicy is loaded from the DB, so now it
only get's loaded when needed.
In preparation for the next commit which will remove the
`*LightningNode` from the `ChannelEdgePolicy` struct,
`FetchLightningNode` is modified to take in an optional transaction so
that it can be utilised in places where a transaction exists.
To prepare for the `kvdb.Backend` member of `ChannelEdgeInfo` being
removed, the `FetchOtherNode` method is moved from the `ChannelEdgeInfo`
to the `ChannelGraph` struct.
Having a `ForEachChannel` method on the `LightningNode` struct itself
results in a `kvdb.Backend` object needing to be stored within the
LightningNode struct. In this commit, this method is replaced with a
`ForEachNodeChannel` method on the `ChannelGraph` struct will perform
the same function without needing the db pointer to be stored within the
LightningNode. This change, the LightningNode struct more closely
represents the schema on disk.
The existing `ForEachNodeChannel` method on `ChannelGraph` is renamed to
`ForEachNodeDirectedChannel`. It performs a slightly different function
since it's call-back operates on Cached policies.
In this commit, we update the Sig type to support ECDSA and schnorr
signatures. We need to do this as the HTLC signatures will become
schnorr sigs for taproot channels. The current spec draft opts to
overload this field since both the sigs are actually 64 bytes in length.
The only consideration with this move is that callers need to "coerce" a
sig to the proper type if they need schnorr signatures.
When a block is disconnected due to a reorg, DisconnectBlockAtHeight
is called for the block height. Prior to this patch, it would delete
every SCID in the graph with a block height greater than the
disconnected height. This meant that a reorg would delete every
zero-conf channel edge from the graph. The fix simply iterates up
until the StartingAlias and deletes every SCID between the
disconnected height and the StartingAlias height.
feature-bit channels
This allows opening zero-conf chan-type, scid-alias chan-type, and
scid-alias feature-bit channels. scid-alias chan-type channels are
required to be private. Two paths are available for opening a zero-conf
channel:
* explicit chan-type negotiation
* LDK carve-out where chan-types are not used, LND is on the
receiving end, and a ChannelAcceptor is used to enable zero-conf
When a zero-conf channel is negotiated, the funding manager:
* sends a FundingLocked with an alias
* waits for a FundingLocked from the remote peer
* calls addToRouterGraph to persist the channel using our alias in
the graph. The peer's alias is used to send them a ChannelUpdate.
* wait for six confirmations. If public, the alias edge in the
graph is deleted and replaced (not atomically) with the confirmed
edge. Our policy is also read-and-replaced, but the counterparty's
policy won't exist until they send it to us.
When a scid-alias-feature channel is negotiated, the funding manager:
* sends a FundingLocked with an alias:
* calls addToRouterGraph, sends ChannelUpdate with the confirmed SCID
since it exists.
* when six confirmations occurs, the edge is deleted and re-inserted
since the peer may have sent us an alias ChannelUpdate that we are
storing in the graph.
Since it is possible for a user to toggle the scid-alias-feature-bit
to on while channels exist in the funding manager, care has been taken
to ensure that an alias is ALWAYS sent in the funding_locked message
if this happens.
An OptionalMsgField has been added that allows outside subsystems
to provide a short channel id we should insert into a ChannelUpdate
that we then sign and send to our peer.
When the gossiper receives a ChannelUpdate, it will query the
alias manager by the passed-in FindBaseByAlias function to determine
if the short channel id in the ChannelUpdate points to a known
channel. If this lookup returns an error, we'll fallback to using
the original id in the ChannelUpdate when querying the router.
The lookup and potential fallback must occur in order to properly
lock the multimutex, query the correct router channels, and rate
limit the correct short channel id. An unfortunate side effect of
receiving ChannelUpdates from our peer that reference on of our
aliases rather than the real SCID is that we must store this policy.
Yet it is not broadcast-able. Care has been taken to ensure the
gossiper does not broadcast *any* ChannelUpdate with an alias SCID.
The cachedNetworkMsg uses the new processedNetworkMsg struct. This
is necessary so that delete-and-reinsert in the funding manager
doesn't process a ChannelUpdate twice and end up in a deadlock since
the err chan is no longer being used.
This commit was previously split into the following parts to ease
review:
- 2d746f68: replace imports
- 4008f0fd: use ecdsa.Signature
- 849e33d1: remove btcec.S256()
- b8f6ebbd: use v2 library correctly
- fa80bca9: bump go modules
In this commit, we modify the implementation of ForEachChannel to
utilize the new kvdb method ForAll. This greatly reduces the number of
round-trips to the database needed to iterate over all channels
in the graph.
In case the channeldb package is used as a library in external tools, it
can be useful to allow read-only access to a DB. This allows such a
tool to access a DB even if not all migrations were executed, which can
be useful for recovery purposes.
To make it possible to even start the DB with a read-only backend, we
need to disable the automatic migration step.
This commit, adds a new ForEachNode method to the channel graph cache
that assumes the contents won't be modified. This is generally useful,
and will be used in a later commit to optimize some heavy RPC calls.
This commit partially reverts bf27d05a.
To avoid creating multiple database transactions during a single path
finding operation, we create an explicit transaction when the cached
graph is instantiated.
We cache the source node to avoid needing to look that up for every path
finding session.
The database transaction will be nil in case of the in-memory graph.
With this commit we forward the config option for disabling the channel
graph cache as a boolean to the channeldb. But we invert its meaning to
make the flag easier to understand.
Fixes#5830.
When a channel for a node is announced before the node itself is
announced on the network, it's possible that we have channels for a node
but no features defined yet. This was previously logged as a warning
which spammed the log unnecessarily.
With this commit we use an optimized version of the node iteration that
causes fewer memory allocations by only loading the part of the graph
node that we actually need to know for the cache.
To avoid the channel map needing to be re-grown while we fill the cache
initially, we might as well pre-allocate it with a somewhat sane value
to decrease the number of grow events.
