From c1511b92cc9c215224314be38c28ed80843f55e4 Mon Sep 17 00:00:00 2001 From: "Ondrej Zajicek (work)" Date: Mon, 10 May 2021 20:09:31 +0200 Subject: [PATCH] Babel: Log the reason when refusing to run on an interface MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The babel protocol code checks whether iface supports multicast, and whether it has a link-local address assigned. However, it doesn not give any feedback if any of those checks fail, it just silently ignores the interface. Fix this by explicitly logging when multicast check fails. Based on patch from Toke Høiland-Jørgensen, thanks! --- proto/babel/babel.c | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) diff --git a/proto/babel/babel.c b/proto/babel/babel.c index 4b6b9d7f..25d8e330 100644 --- a/proto/babel/babel.c +++ b/proto/babel/babel.c @@ -1639,6 +1639,20 @@ babel_remove_iface(struct babel_proto *p, struct babel_iface *ifa) rfree(ifa->pool); /* contains ifa itself, locks, socket, etc */ } +static int +iface_is_valid(struct babel_proto *p, struct iface *iface) +{ + if (!(iface->flags & IF_MULTICAST)) + { + log(L_ERR "%s: Interface %s does not support multicast", + p->p.name, iface->name); + + return 0; + } + + return 1; +} + static void babel_if_notify(struct proto *P, unsigned flags, struct iface *iface) { @@ -1658,16 +1672,13 @@ babel_if_notify(struct proto *P, unsigned flags, struct iface *iface) if (!(iface->flags & IF_UP)) return; - /* We only speak multicast */ - if (!(iface->flags & IF_MULTICAST)) - return; - /* Ignore ifaces without link-local address */ if (!iface->llv6) return; struct babel_iface_config *ic = (void *) iface_patt_find(&cf->iface_list, iface, NULL); - if (ic) + + if (ic && iface_is_valid(p, iface)) babel_add_iface(p, iface, ic); return; @@ -1736,10 +1747,6 @@ babel_reconfigure_ifaces(struct babel_proto *p, struct babel_config *cf) if (!(iface->flags & IF_UP)) continue; - /* Ignore non-multicast ifaces */ - if (!(iface->flags & IF_MULTICAST)) - continue; - /* Ignore ifaces without link-local address */ if (!iface->llv6) continue; @@ -1747,6 +1754,9 @@ babel_reconfigure_ifaces(struct babel_proto *p, struct babel_config *cf) struct babel_iface *ifa = babel_find_iface(p, iface); struct babel_iface_config *ic = (void *) iface_patt_find(&cf->iface_list, iface, NULL); + if (ic && iface_is_valid(p, iface)) + ic = NULL; + if (ifa && ic) { if (babel_reconfigure_iface(p, ifa, ic))