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0c4b51f005
This is immediately motivated by the bridge code that chains functions that call into netfilter. Without passing net into the okfns the bridge code would need to guess about the best expression for the network namespace to process packets in. As net is frequently one of the first things computed in continuation functions after netfilter has done it's job passing in the desired network namespace is in many cases a code simplification. To support this change the function dst_output_okfn is introduced to simplify passing dst_output as an okfn. For the moment dst_output_okfn just silently drops the struct net. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
177 lines
4.0 KiB
C
177 lines
4.0 KiB
C
/*
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* xfrm6_output.c - Common IPsec encapsulation code for IPv6.
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* Copyright (C) 2002 USAGI/WIDE Project
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* Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/if_ether.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/skbuff.h>
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#include <linux/icmpv6.h>
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#include <linux/netfilter_ipv6.h>
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#include <net/dst.h>
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#include <net/ipv6.h>
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#include <net/ip6_route.h>
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#include <net/xfrm.h>
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int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
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u8 **prevhdr)
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{
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return ip6_find_1stfragopt(skb, prevhdr);
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}
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EXPORT_SYMBOL(xfrm6_find_1stfragopt);
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static int xfrm6_local_dontfrag(struct sk_buff *skb)
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{
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int proto;
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struct sock *sk = skb->sk;
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if (sk) {
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if (sk->sk_family != AF_INET6)
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return 0;
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proto = sk->sk_protocol;
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if (proto == IPPROTO_UDP || proto == IPPROTO_RAW)
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return inet6_sk(sk)->dontfrag;
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}
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return 0;
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}
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static void xfrm6_local_rxpmtu(struct sk_buff *skb, u32 mtu)
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{
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struct flowi6 fl6;
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struct sock *sk = skb->sk;
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fl6.flowi6_oif = sk->sk_bound_dev_if;
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fl6.daddr = ipv6_hdr(skb)->daddr;
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ipv6_local_rxpmtu(sk, &fl6, mtu);
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}
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void xfrm6_local_error(struct sk_buff *skb, u32 mtu)
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{
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struct flowi6 fl6;
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const struct ipv6hdr *hdr;
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struct sock *sk = skb->sk;
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hdr = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
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fl6.fl6_dport = inet_sk(sk)->inet_dport;
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fl6.daddr = hdr->daddr;
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ipv6_local_error(sk, EMSGSIZE, &fl6, mtu);
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}
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static int xfrm6_tunnel_check_size(struct sk_buff *skb)
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{
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int mtu, ret = 0;
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struct dst_entry *dst = skb_dst(skb);
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mtu = dst_mtu(dst);
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if (mtu < IPV6_MIN_MTU)
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mtu = IPV6_MIN_MTU;
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if (!skb->ignore_df && skb->len > mtu) {
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skb->dev = dst->dev;
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if (xfrm6_local_dontfrag(skb))
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xfrm6_local_rxpmtu(skb, mtu);
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else if (skb->sk)
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xfrm_local_error(skb, mtu);
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else
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icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
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ret = -EMSGSIZE;
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}
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return ret;
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}
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int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
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{
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int err;
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err = xfrm6_tunnel_check_size(skb);
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if (err)
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return err;
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XFRM_MODE_SKB_CB(skb)->protocol = ipv6_hdr(skb)->nexthdr;
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return xfrm6_extract_header(skb);
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}
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int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
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{
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int err;
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err = xfrm_inner_extract_output(x, skb);
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if (err)
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return err;
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skb->ignore_df = 1;
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skb->protocol = htons(ETH_P_IPV6);
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return x->outer_mode->output2(x, skb);
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}
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EXPORT_SYMBOL(xfrm6_prepare_output);
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int xfrm6_output_finish(struct sock *sk, struct sk_buff *skb)
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{
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memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
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#ifdef CONFIG_NETFILTER
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IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
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#endif
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return xfrm_output(sk, skb);
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}
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static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
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{
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struct dst_entry *dst = skb_dst(skb);
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struct xfrm_state *x = dst->xfrm;
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int mtu;
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#ifdef CONFIG_NETFILTER
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if (!x) {
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IP6CB(skb)->flags |= IP6SKB_REROUTED;
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return dst_output(sk, skb);
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}
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#endif
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if (skb->protocol == htons(ETH_P_IPV6))
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mtu = ip6_skb_dst_mtu(skb);
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else
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mtu = dst_mtu(skb_dst(skb));
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if (skb->len > mtu && xfrm6_local_dontfrag(skb)) {
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xfrm6_local_rxpmtu(skb, mtu);
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return -EMSGSIZE;
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} else if (!skb->ignore_df && skb->len > mtu && skb->sk) {
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xfrm_local_error(skb, mtu);
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return -EMSGSIZE;
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}
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if (x->props.mode == XFRM_MODE_TUNNEL &&
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((skb->len > mtu && !skb_is_gso(skb)) ||
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dst_allfrag(skb_dst(skb)))) {
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return ip6_fragment(sk, skb,
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x->outer_mode->afinfo->output_finish);
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}
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return x->outer_mode->afinfo->output_finish(sk, skb);
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}
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int xfrm6_output(struct sock *sk, struct sk_buff *skb)
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{
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struct net *net = dev_net(skb_dst(skb)->dev);
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return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
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net, sk, skb, NULL, skb_dst(skb)->dev,
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__xfrm6_output,
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!(IP6CB(skb)->flags & IP6SKB_REROUTED));
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}
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