# BGP

This crate provides the `bgp` binary which runs the Border Gateway Protocol
daemon together with its HTTP API.

```
cargo run -- path/to/config.textpb
```

The configuration format is defined in `crates/server/proto/config.proto`;
`testdata/server.textpb` is a worked example. When `http_endpoint` is set the
binary also serves:

| Path | Purpose |
|---|---|
| `GET /statusz` | Status page: peers, announce form, local and received routes, live event log |
| `GET /api/status` | Router ID, ASN, uptime and table sizes |
| `GET /api/peers` | Established sessions |
| `GET /api/routes/local` | Locally originated routes |
| `POST /api/routes/local` | Announce a route (JSON body, see below) |
| `DELETE /api/routes/local` | Withdraw a route (JSON body: `prefix`, optional `owner`) |
| `GET /api/routes/local/wire?prefix=…` | The exact UPDATE bytes sent to each peer |
| `GET /api/routes/received` | Adj-RIB-In contents |
| `GET /api/communities/well-known` | Names accepted in place of numeric communities |
| `GET /api/events` | Server-sent events for session and route changes |
| `GET /metricz` | Prometheus metrics |

Announce body:

```json
{
  "prefix": "10.100.1.0/24",
  "owner": "alice",
  "origin": "IGP",
  "prepend": 2,
  "med": 100,
  "communities": ["65000:100", "NO_EXPORT"],
  "large_communities": ["65000:1:2"]
}
```

Only `prefix` and `owner` are required. Routes are subject to the
`local_route_policy` in the configuration.

## Trying it without a router

`fake_peer` is a minimal BGP speaker that connects to the daemon, announces a
prefix, prints every UPDATE it receives and, with `--echo`, re-announces each
received prefix back with its own ASN prepended (dropping NO_EXPORT routes).
That makes locally announced prefixes show up in the received table as if
they had travelled through a neighbouring AS:

```
cargo run -- testdata/server.textpb
cargo run -p bgp-integration-tests --example fake_peer -- \
    --server 127.0.0.1:179 --asn 65001 --announce 203.0.113.0/24 --echo
```

Please refer to the other implementation crates in this repository where most
of the actual implementation lives.

Warning: This is still very much a work in progress and is not yet ready for
production use.