This change was largely motivated by an increase in high disk usage as a
result of channel update spam. With an in memory graph, this would've
gone mostly undetected except for the increased bandwidth usage, which
this doesn't aim to solve yet. To minimize the effects to disks, we
begin to rate limit channel updates in two ways. Keep alive updates,
those which only increase their timestamps to signal liveliness, are now
limited to one per lnd's rebroadcast interval (current default of 24H).
Non keep alive updates are now limited to one per block per direction.
In this commit, we add a field to the ChannelUpdate
denoting the maximum HTLC we support sending over
this channel, a field which was recently added to the
spec.
This field serves multiple purposes. In the short
term, it enables nodes to signal the largest HTLC
they're willing to carry, allows light clients who
don't verify channel existence to have some guidance
when routing HTLCs, and finally may allow nodes to
preserve a portion of bandwidth at all times.
In the long term, this field can be used by
implementations of AMP to guide payment splitting,
as it becomes apparent to a node the largest possible
HTLC one can route over a particular channel.
This PR was made possible by the merge of #1825,
which enables older nodes to properly retain and
verify signatures on updates that include new fields
(like this new max HTLC field) that they haven't yet
been updated to recognize.
In addition, the new ChannelUpdate fields are added to
the lnwire fuzzing tests.
Co-authored-by: Johan T. Halseth <johanth@gmail.com>
In this commit, we fix the problem where it's annoying to parse a
bitfield printed out in decimal by writing a String method for the
ChanUpdate[Chan|Msg]Flags bitfield.
Co-authored-by: Johan T. Halseth <johanth@gmail.com>
In this commit:
* we partition lnwire.ChanUpdateFlag into two (ChanUpdateChanFlags and
ChanUpdateMsgFlags), from a uint16 to a pair of uint8's
* we rename the ChannelUpdate.Flags to ChannelFlags and add an
additional MessageFlags field, which will be used to indicate the
presence of the optional field HtlcMaximumMsat within the ChannelUpdate.
* we partition ChannelEdgePolicy.Flags into message and channel flags.
This change corresponds to the partitioning of the ChannelUpdate's Flags
field into MessageFlags and ChannelFlags.
Co-authored-by: Johan T. Halseth <johanth@gmail.com>
In this commit, we export the ReadElements and WriteElements functions.
We do this as exporting these functions makes it possible for outside
packages to define serializations which use the BOLT 1.0 wire format.
In this commit, we add a new field to all the existing gossip messages:
ExtraOpqueData. We do this, as before this commit, if we came across a
ChannelUpdate message with a set of optional fields, then we wouldn't be
able to properly parse the signatures related to the message. If we
never corrected this behavior, then we would violate the forwards
compatible principle we use when parsing existing messages.
As these messages can now be padded out to the max message size, we've
increased the MaxPayloadLength value for all of these messages.
Fixes#1814.
In this commit, we add a new type to the lnwire package:
ChanUpdateFlag. This type represent the bitfield that’s used within the
ChannelUpdate message to give additional details as how the message
should be interpreted.
This commit modifies the Message interface to convert the Command
method to a MsgType method that uses a new set of message type for all
the defined messages. These new messages types nearly exactly match the
message types used within the current draft of the BOLT specifications.
This commit revues the Validate method from the Message interface as
the method is no longer used and is a relic from an older version of
the codebase.
