From b7ddd2ec481969bdfcd576c52a6e99c4489ece58 Mon Sep 17 00:00:00 2001 From: Donald Sharp Date: Tue, 14 Feb 2017 20:03:18 -0500 Subject: [PATCH] pimd: Intelligently drop wrvifwhole packets in some cases Suppose we have this (*,G) IIF = swp1 OIL: swp3 (S,G) IIF = swp2 OIL: swp3 swp4 There exists situations where we can receive the mcast packet for (S,G) on both swp1 and swp2. In this case the packet received on swp1 will be sent from the kernel to us as a WRVIF and WRVIFWHOLE. As per normal, WRVIF packet processing handles the assert case so we know we have not received the packet on a downstream interface, so no assert. The WRVIFWHOLE packet processing can then check to see if it received the packet as a result of the (*,G) mroute from upstream. If we have then we can safely drop the packet. Signed-off-by: Donald Sharp --- pimd/pim_mroute.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/pimd/pim_mroute.c b/pimd/pim_mroute.c index 4fae5b3ca5..ae5d0e9891 100644 --- a/pimd/pim_mroute.c +++ b/pimd/pim_mroute.c @@ -351,7 +351,7 @@ pim_mroute_msg_wrvifwhole (int fd, struct interface *ifp, const char *buf) struct pim_interface *pim_ifp; struct pim_ifchannel *ch; struct pim_upstream *up; - //struct prefix_sg star_g; + struct prefix_sg star_g; struct prefix_sg sg; struct channel_oil *oil; @@ -367,9 +367,10 @@ pim_mroute_msg_wrvifwhole (int fd, struct interface *ifp, const char *buf) ch->sg_str, ifp->name); return -1; } -#if 0 + star_g = sg; star_g.src.s_addr = INADDR_ANY; +#if 0 ch = pim_ifchannel_find(ifp, &star_g); if (ch) { @@ -383,11 +384,22 @@ pim_mroute_msg_wrvifwhole (int fd, struct interface *ifp, const char *buf) up = pim_upstream_find (&sg); if (up) { + struct pim_upstream *parent; struct pim_nexthop source; struct pim_rpf *rpf = RP (sg.grp); if (!rpf || !rpf->source_nexthop.interface) return 0; + /* + * If we have received a WRVIFWHOLE and are at this + * point, we could be receiving the packet on the *,G + * tree, let's check and if so we can safely drop + * it. + */ + parent = pim_upstream_find (&star_g); + if (parent && parent->rpf.source_nexthop.interface == ifp) + return 0; + pim_ifp = rpf->source_nexthop.interface->info; memset (&source, 0, sizeof (source)); -- 2.39.5