xdp-project-bpf-examples/nat64-bpf

• NAT64 BPF implementation

NAT64 BPF implementation

This directory contains a BPF implementation of a stateless NAT64 implementation, like that performed by Tayga, but entirely in BPF.

Design:

• Global v6 /96 prefix defined as NAT64 prefix

• Each interface is assigned a v4 prefix for mapping v6 addresses

  • Install onlink v4 route for that prefix to make sure traffic goes out the interface

• Attach ingress and egress BPF programs to each interface

  • On ingress: match v6 packets with a NAT64 prefix destination; remap to v4
  • On egress: lookup v4 destination address; if it's in the configured NAT64 prefix, remap back to v6
• Some logic to dynamically assign v4 addresses each time a new v6 source is seen