995908dc5b
[ Upstream commit 0c922a4850eba2e668f73a3f1153196e09abb251 ] IPSKB_XFRM_TRANSFORMED and IP6SKB_XFRM_TRANSFORMED are skb flags set by xfrm code to tell other skb handlers that the packet has been passed through the xfrm output functions. Simplify the code and just always set them rather than conditionally based on netfilter enabled thus making the flag available for other users. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
193 lines
4.3 KiB
C
193 lines
4.3 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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if (skb->ignore_df)
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goto out;
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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_is_gso(skb) && skb->len > mtu) ||
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(skb_is_gso(skb) &&
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!skb_gso_validate_network_len(skb, ip6_skb_dst_mtu(skb)))) {
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skb->dev = dst->dev;
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skb->protocol = htons(ETH_P_IPV6);
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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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out:
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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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IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
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return xfrm_output(sk, skb);
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}
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static int __xfrm6_output_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
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{
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struct xfrm_state *x = skb_dst(skb)->xfrm;
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return x->outer_mode->afinfo->output_finish(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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bool toobig;
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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(net, sk, skb);
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}
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#endif
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if (x->props.mode != XFRM_MODE_TUNNEL)
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goto skip_frag;
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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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toobig = skb->len > mtu && !skb_is_gso(skb);
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if (toobig && xfrm6_local_dontfrag(skb)) {
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xfrm6_local_rxpmtu(skb, mtu);
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kfree_skb(skb);
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return -EMSGSIZE;
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} else if (!skb->ignore_df && toobig && skb->sk) {
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xfrm_local_error(skb, mtu);
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kfree_skb(skb);
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return -EMSGSIZE;
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}
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if (toobig || dst_allfrag(skb_dst(skb)))
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return ip6_fragment(net, sk, skb,
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__xfrm6_output_finish);
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skip_frag:
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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 net *net, struct sock *sk, struct sk_buff *skb)
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{
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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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