From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: [PATCH net-next 06/13] net: original ingress device index in PKTINFO Date: Wed, 4 May 2016 20:33:23 -0700 Message-ID: <1462419210-10463-7-git-send-email-dsa@cumulusnetworks.com> References: <1462419210-10463-1-git-send-email-dsa@cumulusnetworks.com> Cc: David Ahern To: netdev@vger.kernel.org Return-path: Received: from mail-pa0-f45.google.com ([209.85.220.45]:33463 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755817AbcEEDeP (ORCPT ); Wed, 4 May 2016 23:34:15 -0400 Received: by mail-pa0-f45.google.com with SMTP id xk12so31293061pac.0 for ; Wed, 04 May 2016 20:34:15 -0700 (PDT) In-Reply-To: <1462419210-10463-1-git-send-email-dsa@cumulusnetworks.com> Sender: netdev-owner@vger.kernel.org List-ID: Applications such as OSPF and BFD need the original ingress device not the VRF device; the latter can be derived from the former. To that end add the skb_iif to inet_skb_parm and set it in ipv4 code after clearing the skb control buffer similar to IPv6. From there the pktinfo can just pull it from cb with the PKTINFO_SKB_CB cast. The previous patch moving the skb->dev change to L3 means nothing else is needed for IPv6; it just works. Signed-off-by: David Ahern --- include/net/ip.h | 1 + net/ipv4/ip_input.c | 1 + net/ipv4/ip_sockglue.c | 9 +++++++-- 3 files changed, 9 insertions(+), 2 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index 247ac82e9cf2..37165fba3741 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -36,6 +36,7 @@ struct sock; struct inet_skb_parm { + int iif; struct ip_options opt; /* Compiled IP options */ unsigned char flags; diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index 37375eedeef9..4b351af3e67b 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -478,6 +478,7 @@ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, /* Remove any debris in the socket control block */ memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); + IPCB(skb)->iif = skb->skb_iif; /* Must drop socket now because of tproxy. */ skb_orphan(skb); diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index bdb222c0c6a2..dbcd027c38e7 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -476,9 +476,9 @@ static bool ipv4_datagram_support_cmsg(const struct sock *sk, (!skb->dev)) return false; + /* see comment in ipv4_pktinfo_prepare about CB re-use */ info = PKTINFO_SKB_CB(skb); info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr; - info->ipi_ifindex = skb->dev->ifindex; return true; } @@ -1193,7 +1193,12 @@ void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb) ipv6_sk_rxinfo(sk); if (prepare && skb_rtable(skb)) { - pktinfo->ipi_ifindex = inet_iif(skb); + /* skb->cb is overloaded: prior to this point it is IP{6}CB + * which has interface index (iif) as the first member of the + * underlying inet{6}_skb_parm struct. This code then overlays + * PKTINFO_SKB_CB and in_pktinfo also has iif as the first + * element so the iif is picked up from the prior IPCB + */ pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb); } else { pktinfo->ipi_ifindex = 0; -- 2.1.4