draft-yang-bgp-communities

This document provides a YANG module for specifying BGP communities, Extended BGP communities and Large BGP communities. The purpose of this is to provide a standardized way for publishing community definitions. It also helps applications such as looking glasses to interpret communities seen in BGP announcements.

Contents

This repository contains the following files:

• draft/draft-yang-bgp-communities.xml - XML specification of the draft
• draft/draft-yang-bgp-communities.txt - The draft in plain text format, generated using xml2rfc
• draft/draft-yang-bgp-communities.html - The draft in html format, generated using xml2rfc
• yang/draft-ietf-grow-yang-bgp-communities.yang - The YANG model, verified using yanglint
• scripts/parser.py - An example parser
• scripts/convertcbor.py - A tool for converting from JSON to CBOR and vice versa
• examples/bgp-communities.json - An example JSON specification conforming to the YANG model
• examples/rfc4384.json - Example JSON specification for RFC4384 communities used in the draft
• examples/rfc8195.json - Example JSON specification for RFC8195 community used in the draft
• examples/*.txt - Example communities to match using the JSON specification
• examples/*.out - Example output of the parser
• resources/inventory.md - A non-exhaustive list of BGP community definitions found on the web

Usage

Generate the draft:

xml2rfc --v3 --text --html draft/draft-yang-bgp-communities.xml

Display the YANG module tree:

git clone https://github.com/YangModels/yang.git YangModels
ln -s YangModels/experimental/ietf-extracted-YANG-modules ietf-yang
pyang --verbose --ietf -p ietf-yang:yang -f tree  yang/ietf-bgp-communities.yang
pyang --verbose --ietf -p ietf-yang:yang -f tree  yang/ietf-bgp-communities-annotate.yang
pyang --verbose --ietf -p ietf-yang:yang -f tree --tree-print-groupings ietf-yang/ietf-bgp@2024-10-21.yang yang/ietf-bgp-communities-annotate.yang

Validate the JSON specification using the YANG model:

yanglint -p ietf-yang yang/ietf-bgp-communities.yang examples/bgp-communities.json
yanglint -p ietf-yang yang/ietf-bgp-communities-annotate.yang examples/ietf-bgp.json

Generate a SID file from the YANG model (using Experimental/Private SIDs):

cat yang/ietf-bgp-communities.yang | pyang -p yang --sid-generate-file 60000:100

Parse the example communities using example JSON specifications:

scripts/parser.py examples/bgp-communities.txt examples/bgp-communities.json
scripts/parser.py examples/rfc8195.txt examples/rfc8195.json
scripts/parser.py examples/rfc4384.txt examples/rfc4384.json

Convert the example JSON specification to a CBOR file:

python3 -m venv scripts
scripts/bin/pip install cbor2
PATH=scripts/bin:$PATH
scripts/convertcbor.py --j2c -j examples/bgp-communities.json -c examples/bgp-communities.cbor
scripts/convertcbor.py --j2c -j examples/bgp-communities.json -s *.sid -c examples/bgp-communities-sids.cbor

Convert a CBOR file to JSON:

scripts/convertcbor.py --c2j -c <in.cbor> [-s *.sid] -j <out.json>

Sign a JSON file:

scripts/bin/pip install jwcrypto rfc8785
openssl ecparam -genkey -name secp521r1 -noout -out jws.key
openssl ec -in jws.key -pubout -out jws.pub
scripts/jwstool.py -s -k jws.key examples/bgp-communities.json

Validate the signed JSON:

scripts/jwstool.py -v -k jws.pub examples/bgp-communities.json

## Implementations

The following known implementations exist.

### Publishing ASNs

* [AS197000](https://www-static.ripe.net/dynamic/draft-ietf-grow-yang-bgp-communities/as197000.json)
* [AS25152](https://www-static.ripe.net/dynamic/draft-ietf-grow-yang-bgp-communities/as25152.json)

### Parsers

* [NLNOG Looking Glass](https://github.com/NLNOG/lg.ring.nlnog.net/)