ppad-bolt7

A pure Haskell implementation of BOLT #7 (Lightning Network routing gossip protocol).

Usage

A sample GHCi session:

  > :set -XOverloadedStrings
  >
  > -- import qualified
  > import qualified Lightning.Protocol.BOLT7 as B7
  >
  > -- decode a gossip_timestamp_filter from wire bytes (after msg type)
  > -- wire contains: 32-byte chain_hash, 4-byte first_timestamp,
  > --                4-byte timestamp_range
  > case B7.decodeGossipTimestampFilter wire of
  >   Left err -> print err
  >   Right (msg, rest) -> print (B7.gossipFilterFirstTimestamp msg)
  1609459200
  >
  > -- construct and encode a gossip_timestamp_filter
  > let msg = B7.GossipTimestampFilter B7.mainnetChainHash 1609459200 86400
  > let encoded = B7.encodeGossipTimestampFilter msg
  >
  > -- validate a channel_announcement before processing
  > case B7.validateChannelAnnouncement announcement of
  >   Left B7.ValidateNodeIdOrdering -> putStrLn "invalid node ordering"
  >   Right () -> putStrLn "valid"
  >
  > -- compute the hash for signature verification
  > let sigHash = B7.channelAnnouncementHash encodedAnnouncement
  > -- verify signatures with ppad-secp256k1 (separate library)

Overview

ppad-bolt7 provides types and codecs for BOLT #7 gossip messages:

• channel_announcement (256)
• node_announcement (257)
• channel_update (258)
• announcement_signatures (259)
• query_short_channel_ids (261)
• reply_short_channel_ids_end (262)
• query_channel_range (263)
• reply_channel_range (264)
• gossip_timestamp_filter (265)

Documentation

Haddock documentation is available at docs.ppad.tech/bolt7.

Security

This is a pre-release version of the library and makes no claims about security whatsoever.

Development

A Nix development shell is provided via flake. Enter it with:

$ nix develop

Then use cabal as usual:

$ cabal build
$ cabal test
$ cabal bench