Files
ferrix/README.md
Rayhaan JaufeerallyandClaude Fable 5.1 39632e3c38 Property tests and fuzz targets for the parsers, and the bugs they found
Property tests (run by `cargo test`):
- crates/packet/tests/properties.rs: every kind of message, generated,
  must be written, be as long as wire_len says, and read back equal; and
  noise, noise behind a valid header, and valid messages with bytes damaged
  must never do more than return an error. Anything the decoder accepts
  must be showable and survive being written and read again.
- IpPrefix: text round trip, noise as text, `contains` against a bitwise
  model.
- The session's framing: a stream of messages yields the same messages
  however it is cut into reads.

Fuzz targets (fuzz/, cargo-fuzz on nightly, a minute each in CI): raw
messages, message bodies behind a valid header, prefix text, the
configuration file.

Bugs found, each with a named regression test:
- A prefix longer than its address family (e.g. an IPv4 NLRI of length 99)
  was accepted, and showing it panicked. The session logs every route, so
  one UPDATE from a peer ended the session task. Such a prefix is now
  malformed, and showing a prefix cannot fail.
- Bits past a prefix's length were kept, so the same prefix sent with stray
  bits was a different key in the RIB. Prefixes now have one form.
- An opaque extended community was read as seven octets instead of eight,
  putting every community after it out of step.
- AGGREGATOR could be neither read from nor written to a peer with
  two-octet AS numbers.
- The Outbound Route Filter and Long-Lived Graceful Restart capabilities
  were written differently from how they are read.
- A capability value or unknown attribute too long for its length field
  was written with the length wrapped around; it is now an error, or for
  the attribute the two-octet length.

Also: ROUTE-REFRESH carries its AFI and SAFI instead of being modelled as
an empty message, and one with a body of the wrong length is refused.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
2026-10-01 22:54:37 +02:00

2.2 KiB

BGP

The bgp crate is an implementation of the Border Gateway Protocol, which is used to exchange routing and control plane information between Autonomous Systems.

The aim of this project is to provide a modern, high performance, secure, programmatic and customizable software package that can be useful to network operators, researchers, and people interested in Internet.

Current status.

The project is currently being rewritten from scratch to be more modular and maintainable, as well as to fix deeper issues with the previous implementation.

⚠️ Warning: This is currently a work in progress and not ready for use.

🛣️ Roadmap to v1.0

We aim for the 1.0 release to be functional and stable to operate peering sessions, and to install routes in the Linux Kernel.

  • ☐ Implement basic parsers for the fundamental types required
    • ✅ Path Attributes from RFC4271
    • ✅ Open message
      • ✅ Capabilities from RFC4271
    • ✅ Update message
    • ☐ Notification message
  • ✅ Implement scaffolding required to start and configure a server
  • ✅ Implement connection logic to establish sessions with peers (passive and active)
  • ✅ Routes originated from the configuration, with communities, announced to all peers
  • ✅ Read-only HTTP API, status page and Prometheus metrics
  • ☐ Implement an efficient data structure for storing prefixes (e.g. Poptrie)
  • ☐ Filtering for peer RIB in / out
  • ☐ Main / auxiliary RIBs for exchanging routes between peers

Development

CI runs these three on every push, and fails on any warning:

cargo fmt --all -- --check
cargo clippy --workspace --all-targets -- -D warnings
cargo test --workspace

Lints are configured once, under [workspace.lints] in the root Cargo.toml. unsafe code is forbidden throughout.

cargo test includes property tests: generated messages must survive being written and read back, and no input, however damaged, may make a parser panic. They take about a second; for a longer hunt:

PROPTEST_CASES=1000000 cargo test --release -p bgp-packet --test properties

Coverage-guided fuzz targets for the same parsers are in fuzz/; see fuzz/README.md. CI runs each of them for a minute.

License

Apache License 2.0; see LICENSE.