From c8b34e680a090ab8dc42f8331020e31052b49a70 Mon Sep 17 00:00:00 2001 From: wenxu Date: Tue, 22 Jan 2019 18:39:50 +0800 Subject: ip_tunnel: Add tnl_update_pmtu in ip_md_tunnel_xmit Add tnl_update_pmtu in ip_md_tunnel_xmit to dynamic modify the pmtu which packet send through collect_metadata mode ip tunnel Signed-off-by: wenxu Signed-off-by: David S. Miller --- net/ipv4/ip_tunnel.c | 37 +++++++++++++++++++++++++++---------- net/ipv4/ipip.c | 2 +- 2 files changed, 28 insertions(+), 11 deletions(-) (limited to 'net') diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index f98fc4c983a5..6233a7c434b1 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -501,15 +501,19 @@ EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup); static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, struct rtable *rt, __be16 df, - const struct iphdr *inner_iph) + const struct iphdr *inner_iph, + int tunnel_hlen, __be32 dst, bool md) { struct ip_tunnel *tunnel = netdev_priv(dev); - int pkt_size = skb->len - tunnel->hlen - dev->hard_header_len; + int pkt_size; int mtu; + tunnel_hlen = md ? tunnel_hlen : tunnel->hlen; + pkt_size = skb->len - tunnel_hlen - dev->hard_header_len; + if (df) mtu = dst_mtu(&rt->dst) - dev->hard_header_len - - sizeof(struct iphdr) - tunnel->hlen; + - sizeof(struct iphdr) - tunnel_hlen; else mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu; @@ -527,11 +531,13 @@ static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, #if IS_ENABLED(CONFIG_IPV6) else if (skb->protocol == htons(ETH_P_IPV6)) { struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb); + __be32 daddr; + + daddr = md ? dst : tunnel->parms.iph.daddr; if (rt6 && mtu < dst_mtu(skb_dst(skb)) && mtu >= IPV6_MIN_MTU) { - if ((tunnel->parms.iph.daddr && - !ipv4_is_multicast(tunnel->parms.iph.daddr)) || + if ((daddr && !ipv4_is_multicast(daddr)) || rt6->rt6i_dst.plen == 128) { rt6->rt6i_flags |= RTF_MODIFIED; dst_metric_set(skb_dst(skb), RTAX_MTU, mtu); @@ -548,7 +554,8 @@ static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, return 0; } -void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto) +void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, + u8 proto, int tunnel_hlen) { struct ip_tunnel *tunnel = netdev_priv(dev); u32 headroom = sizeof(struct iphdr); @@ -598,6 +605,15 @@ void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto) dev->stats.collisions++; goto tx_error; } + + if (key->tun_flags & TUNNEL_DONT_FRAGMENT) + df = htons(IP_DF); + if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, tunnel_hlen, + key->u.ipv4.dst, true)) { + ip_rt_put(rt); + goto tx_error; + } + tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); ttl = key->ttl; if (ttl == 0) { @@ -608,10 +624,10 @@ void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto) else ttl = ip4_dst_hoplimit(&rt->dst); } - if (key->tun_flags & TUNNEL_DONT_FRAGMENT) - df = htons(IP_DF); - else if (skb->protocol == htons(ETH_P_IP)) + + if (!df && skb->protocol == htons(ETH_P_IP)) df = inner_iph->frag_off & htons(IP_DF); + headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len; if (headroom > dev->needed_headroom) dev->needed_headroom = headroom; @@ -741,7 +757,8 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, goto tx_error; } - if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) { + if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph, + 0, 0, false)) { ip_rt_put(rt); goto tx_error; } diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c index 57c5dd283a2c..fe10b9a2efc8 100644 --- a/net/ipv4/ipip.c +++ b/net/ipv4/ipip.c @@ -302,7 +302,7 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, skb_set_inner_ipproto(skb, ipproto); if (tunnel->collect_md) - ip_md_tunnel_xmit(skb, dev, ipproto); + ip_md_tunnel_xmit(skb, dev, ipproto, 0); else ip_tunnel_xmit(skb, dev, tiph, ipproto); return NETDEV_TX_OK; -- cgit v1.2.3-59-g8ed1b