From 96812ac2c2b769c977e23c0e55a4667a708193e9 Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Fri, 23 Aug 2019 00:38:47 -0400 Subject: [PATCH] Select only ASNs visible in all paths for an IP --- src/bgp_client.rs | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/src/bgp_client.rs b/src/bgp_client.rs index a96de04..1fa9250 100644 --- a/src/bgp_client.rs +++ b/src/bgp_client.rs @@ -176,13 +176,24 @@ pub struct BGPClient { impl BGPClient { pub fn get_asn(&self, addr: IpAddr) -> u32 { let mut path_vecs = self.routes.lock().unwrap().get_route_attrs(addr).clone(); + if path_vecs.is_empty() { return 0; } + path_vecs.sort_unstable_by(|path_a, path_b| { path_a.pref.cmp(&path_b.pref) .then(path_b.path.len().cmp(&path_a.path.len())) .then(path_b.med.cmp(&path_a.med)) }); - // TODO: Find last common ASN among all paths - *path_vecs.first().map(|route| route.path.last().unwrap_or(&0)).unwrap_or(&0) + + let primary_route = path_vecs.pop().unwrap(); + 'asn_candidates: for asn in primary_route.path.iter().rev() { + for secondary_route in path_vecs.iter() { + if !secondary_route.path.contains(asn) { + continue 'asn_candidates; + } + } + return *asn; + } + *primary_route.path.last().unwrap_or(&0) } pub fn disconnect(&self) { -- 2.39.5