linux/net/ipv6/xfrm6_output.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

194 lines
4.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* xfrm6_output.c - Common IPsec encapsulation code for IPv6.
* Copyright (C) 2002 USAGI/WIDE Project
* Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
*/
#include <linux/if_ether.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/icmpv6.h>
#include <linux/netfilter_ipv6.h>
#include <net/dst.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#include <net/xfrm.h>
int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
u8 **prevhdr)
{
return ip6_find_1stfragopt(skb, prevhdr);
}
EXPORT_SYMBOL(xfrm6_find_1stfragopt);
static int xfrm6_local_dontfrag(struct sk_buff *skb)
{
int proto;
struct sock *sk = skb->sk;
if (sk) {
if (sk->sk_family != AF_INET6)
return 0;
proto = sk->sk_protocol;
if (proto == IPPROTO_UDP || proto == IPPROTO_RAW)
return inet6_sk(sk)->dontfrag;
}
return 0;
}
static void xfrm6_local_rxpmtu(struct sk_buff *skb, u32 mtu)
{
struct flowi6 fl6;
struct sock *sk = skb->sk;
fl6.flowi6_oif = sk->sk_bound_dev_if;
fl6.daddr = ipv6_hdr(skb)->daddr;
ipv6_local_rxpmtu(sk, &fl6, mtu);
}
void xfrm6_local_error(struct sk_buff *skb, u32 mtu)
{
struct flowi6 fl6;
const struct ipv6hdr *hdr;
struct sock *sk = skb->sk;
hdr = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
fl6.fl6_dport = inet_sk(sk)->inet_dport;
fl6.daddr = hdr->daddr;
ipv6_local_error(sk, EMSGSIZE, &fl6, mtu);
}
static int xfrm6_tunnel_check_size(struct sk_buff *skb)
{
int mtu, ret = 0;
struct dst_entry *dst = skb_dst(skb);
if (skb->ignore_df)
goto out;
mtu = dst_mtu(dst);
if (mtu < IPV6_MIN_MTU)
mtu = IPV6_MIN_MTU;
if ((!skb_is_gso(skb) && skb->len > mtu) ||
(skb_is_gso(skb) &&
!skb_gso_validate_network_len(skb, ip6_skb_dst_mtu(skb)))) {
skb->dev = dst->dev;
skb->protocol = htons(ETH_P_IPV6);
if (xfrm6_local_dontfrag(skb))
xfrm6_local_rxpmtu(skb, mtu);
else if (skb->sk)
xfrm_local_error(skb, mtu);
else
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
ret = -EMSGSIZE;
}
out:
return ret;
}
int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
{
int err;
err = xfrm6_tunnel_check_size(skb);
if (err)
return err;
XFRM_MODE_SKB_CB(skb)->protocol = ipv6_hdr(skb)->nexthdr;
return xfrm6_extract_header(skb);
}
int xfrm6_output_finish(struct sock *sk, struct sk_buff *skb)
{
memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
#ifdef CONFIG_NETFILTER
IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
#endif
return xfrm_output(sk, skb);
}
static int __xfrm6_output_state_finish(struct xfrm_state *x, struct sock *sk,
struct sk_buff *skb)
{
const struct xfrm_state_afinfo *afinfo;
int ret = -EAFNOSUPPORT;
rcu_read_lock();
afinfo = xfrm_state_afinfo_get_rcu(x->outer_mode.family);
if (likely(afinfo))
ret = afinfo->output_finish(sk, skb);
else
kfree_skb(skb);
rcu_read_unlock();
return ret;
}
static int __xfrm6_output_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct xfrm_state *x = skb_dst(skb)->xfrm;
return __xfrm6_output_state_finish(x, sk, skb);
}
static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
struct xfrm_state *x = dst->xfrm;
int mtu;
bool toobig;
#ifdef CONFIG_NETFILTER
if (!x) {
IP6CB(skb)->flags |= IP6SKB_REROUTED;
return dst_output(net, sk, skb);
}
#endif
if (x->props.mode != XFRM_MODE_TUNNEL)
goto skip_frag;
if (skb->protocol == htons(ETH_P_IPV6))
mtu = ip6_skb_dst_mtu(skb);
else
mtu = dst_mtu(skb_dst(skb));
toobig = skb->len > mtu && !skb_is_gso(skb);
if (toobig && xfrm6_local_dontfrag(skb)) {
xfrm6_local_rxpmtu(skb, mtu);
kfree_skb(skb);
return -EMSGSIZE;
} else if (!skb->ignore_df && toobig && skb->sk) {
xfrm_local_error(skb, mtu);
kfree_skb(skb);
return -EMSGSIZE;
}
if (toobig || dst_allfrag(skb_dst(skb)))
return ip6_fragment(net, sk, skb,
__xfrm6_output_finish);
skip_frag:
return __xfrm6_output_state_finish(x, sk, skb);
}
int xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
net, sk, skb, NULL, skb_dst(skb)->dev,
__xfrm6_output,
!(IP6CB(skb)->flags & IP6SKB_REROUTED));
}