forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
96 lines
2.6 KiB
96 lines
2.6 KiB
/* |
|
* IPv4 specific functions of netfilter core |
|
* |
|
* Rusty Russell (C) 2000 -- This code is GPL. |
|
* Patrick McHardy (C) 2006-2012 |
|
*/ |
|
#include <linux/kernel.h> |
|
#include <linux/netfilter.h> |
|
#include <linux/netfilter_ipv4.h> |
|
#include <linux/ip.h> |
|
#include <linux/skbuff.h> |
|
#include <linux/gfp.h> |
|
#include <linux/export.h> |
|
#include <net/route.h> |
|
#include <net/xfrm.h> |
|
#include <net/ip.h> |
|
#include <net/netfilter/nf_queue.h> |
|
|
|
/* route_me_harder function, used by iptable_nat, iptable_mangle + ip_queue */ |
|
int ip_route_me_harder(struct net *net, struct sock *sk, struct sk_buff *skb, unsigned int addr_type) |
|
{ |
|
const struct iphdr *iph = ip_hdr(skb); |
|
struct rtable *rt; |
|
struct flowi4 fl4 = {}; |
|
__be32 saddr = iph->saddr; |
|
__u8 flags; |
|
struct net_device *dev = skb_dst(skb)->dev; |
|
struct flow_keys flkeys; |
|
unsigned int hh_len; |
|
|
|
sk = sk_to_full_sk(sk); |
|
flags = sk ? inet_sk_flowi_flags(sk) : 0; |
|
|
|
if (addr_type == RTN_UNSPEC) |
|
addr_type = inet_addr_type_dev_table(net, dev, saddr); |
|
if (addr_type == RTN_LOCAL || addr_type == RTN_UNICAST) |
|
flags |= FLOWI_FLAG_ANYSRC; |
|
else |
|
saddr = 0; |
|
|
|
/* some non-standard hacks like ipt_REJECT.c:send_reset() can cause |
|
* packets with foreign saddr to appear on the NF_INET_LOCAL_OUT hook. |
|
*/ |
|
fl4.daddr = iph->daddr; |
|
fl4.saddr = saddr; |
|
fl4.flowi4_tos = RT_TOS(iph->tos); |
|
fl4.flowi4_oif = sk ? sk->sk_bound_dev_if : 0; |
|
if (!fl4.flowi4_oif) |
|
fl4.flowi4_oif = l3mdev_master_ifindex(dev); |
|
fl4.flowi4_mark = skb->mark; |
|
fl4.flowi4_flags = flags; |
|
fib4_rules_early_flow_dissect(net, skb, &fl4, &flkeys); |
|
rt = ip_route_output_key(net, &fl4); |
|
if (IS_ERR(rt)) |
|
return PTR_ERR(rt); |
|
|
|
/* Drop old route. */ |
|
skb_dst_drop(skb); |
|
skb_dst_set(skb, &rt->dst); |
|
|
|
if (skb_dst(skb)->error) |
|
return skb_dst(skb)->error; |
|
|
|
#ifdef CONFIG_XFRM |
|
if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) && |
|
xfrm_decode_session(skb, flowi4_to_flowi(&fl4), AF_INET) == 0) { |
|
struct dst_entry *dst = skb_dst(skb); |
|
skb_dst_set(skb, NULL); |
|
dst = xfrm_lookup(net, dst, flowi4_to_flowi(&fl4), sk, 0); |
|
if (IS_ERR(dst)) |
|
return PTR_ERR(dst); |
|
skb_dst_set(skb, dst); |
|
} |
|
#endif |
|
|
|
/* Change in oif may mean change in hh_len. */ |
|
hh_len = skb_dst(skb)->dev->hard_header_len; |
|
if (skb_headroom(skb) < hh_len && |
|
pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)), |
|
0, GFP_ATOMIC)) |
|
return -ENOMEM; |
|
|
|
return 0; |
|
} |
|
EXPORT_SYMBOL(ip_route_me_harder); |
|
|
|
int nf_ip_route(struct net *net, struct dst_entry **dst, struct flowi *fl, |
|
bool strict __always_unused) |
|
{ |
|
struct rtable *rt = ip_route_output_key(net, &fl->u.ip4); |
|
if (IS_ERR(rt)) |
|
return PTR_ERR(rt); |
|
*dst = &rt->dst; |
|
return 0; |
|
} |
|
EXPORT_SYMBOL_GPL(nf_ip_route);
|
|
|