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 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 check to HtlcSatifiesPolicy to verify that the
time lock for the outgoing htlc that is requested in the onion packet
isn't too far in the future.
Without this check, anyone could force an unreasonably long time lock on
the forwarding node.
In this commit, we add a compatibility mode for older version of
clightning to ensure that we're able to properly parse all their channel
updates. An older version of c-lightning would send out encapsulated
onion error message with an additional type byte. This would throw off
our parsing as we didn't expect the type byte, and so we always 2 bytes
off. In order to ensure that we're able to parse these messages and make
adjustments to our path finding, we'll first check to see if the type
byte is there, if so, then we'll snip off two bytes from the front and
continue with parsing. if the bytes aren't found, then we can proceed as
normal and parse the request.
In this commit, we add additional detail in the error return hen were’e
unable to properly decode an encapsulated error. This additional
logging was added with the goal of being able to track down a lingering
bug, where at times lnd cannot decode a TemporaryChannelFailure
message.
This commit updates the encoding/decoding for the onion errors to
properly match BOLT-0004. This commit does to major things: we increase
the max message size to 256 bytes to account for recent modifications
to the ChannelUpdate message, and also fold in the error code into the
failure message encapsulation itself.
In this commit onion routing error from BOLT#4 have been added, the
initial error construction have been splitted on two parts: The first
part which contains the actual data will reside inside the lnwire
package because it contains all necessary function to decode/encode
the data. The second part obfuscation and hmac checking will resides
inside the lighting-onion package because it requires the key
generation.
