Contributors: 31
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Linus Torvalds (pre-git) |
263 |
40.40% |
14 |
23.33% |
| Florian Westphal |
98 |
15.05% |
2 |
3.33% |
| Alexey Kuznetsov |
66 |
10.14% |
5 |
8.33% |
| John Heffner |
36 |
5.53% |
1 |
1.67% |
| Eric W. Biedermann |
28 |
4.30% |
6 |
10.00% |
| Hannes Frederic Sowa |
24 |
3.69% |
2 |
3.33% |
| Ido Schimmel |
21 |
3.23% |
1 |
1.67% |
| Sebastian Pöhn |
12 |
1.84% |
1 |
1.67% |
| Denis Kirjanov |
12 |
1.84% |
1 |
1.67% |
| Eric Dumazet |
12 |
1.84% |
4 |
6.67% |
| Ben Hutchings |
10 |
1.54% |
1 |
1.67% |
| David S. Miller |
9 |
1.38% |
1 |
1.67% |
| Vincent Bernat |
9 |
1.38% |
1 |
1.67% |
| Petr Machata |
8 |
1.23% |
1 |
1.67% |
| Arnaldo Carvalho de Melo |
6 |
0.92% |
1 |
1.67% |
| Linus Torvalds |
5 |
0.77% |
1 |
1.67% |
| Wei Dong |
4 |
0.61% |
1 |
1.67% |
| Herbert Xu |
3 |
0.46% |
1 |
1.67% |
| Masahide Nakamura |
3 |
0.46% |
1 |
1.67% |
| Tejun Heo |
3 |
0.46% |
1 |
1.67% |
| Alexey Dobriyan |
3 |
0.46% |
1 |
1.67% |
| Hideaki Yoshifuji / 吉藤英明 |
3 |
0.46% |
2 |
3.33% |
| Pavel Emelyanov |
3 |
0.46% |
2 |
3.33% |
| Thomas Graf |
2 |
0.31% |
1 |
1.67% |
| Marcelo Ricardo Leitner |
2 |
0.31% |
1 |
1.67% |
| Adrian Bunk |
1 |
0.15% |
1 |
1.67% |
| David Ahern |
1 |
0.15% |
1 |
1.67% |
| Jan Engelhardt |
1 |
0.15% |
1 |
1.67% |
| Greg Kroah-Hartman |
1 |
0.15% |
1 |
1.67% |
| Patrick McHardy |
1 |
0.15% |
1 |
1.67% |
| Daniel Axtens |
1 |
0.15% |
1 |
1.67% |
| Total |
651 |
|
60 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* The IP forwarding functionality.
*
* Authors: see ip.c
*
* Fixes:
* Many : Split from ip.c , see ip_input.c for
* history.
* Dave Gregorich : NULL ip_rt_put fix for multicast
* routing.
* Jos Vos : Add call_out_firewall before sending,
* use output device for accounting.
* Jos Vos : Call forward firewall after routing
* (always use output device).
* Mike McLagan : Routing by source
*/
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/icmp.h>
#include <linux/netdevice.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/icmp.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/netfilter_ipv4.h>
#include <net/checksum.h>
#include <linux/route.h>
#include <net/route.h>
#include <net/xfrm.h>
static bool ip_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
{
if (skb->len <= mtu)
return false;
if (unlikely((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0))
return false;
/* original fragment exceeds mtu and DF is set */
if (unlikely(IPCB(skb)->frag_max_size > mtu))
return true;
if (skb->ignore_df)
return false;
if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
return false;
return true;
}
static int ip_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct ip_options *opt = &(IPCB(skb)->opt);
__IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
__IP_ADD_STATS(net, IPSTATS_MIB_OUTOCTETS, skb->len);
#ifdef CONFIG_NET_SWITCHDEV
if (skb->offload_l3_fwd_mark) {
consume_skb(skb);
return 0;
}
#endif
if (unlikely(opt->optlen))
ip_forward_options(skb);
skb->tstamp = 0;
return dst_output(net, sk, skb);
}
int ip_forward(struct sk_buff *skb)
{
u32 mtu;
struct iphdr *iph; /* Our header */
struct rtable *rt; /* Route we use */
struct ip_options *opt = &(IPCB(skb)->opt);
struct net *net;
/* that should never happen */
if (skb->pkt_type != PACKET_HOST)
goto drop;
if (unlikely(skb->sk))
goto drop;
if (skb_warn_if_lro(skb))
goto drop;
if (!xfrm4_policy_check(NULL, XFRM_POLICY_FWD, skb))
goto drop;
if (IPCB(skb)->opt.router_alert && ip_call_ra_chain(skb))
return NET_RX_SUCCESS;
skb_forward_csum(skb);
net = dev_net(skb->dev);
/*
* According to the RFC, we must first decrease the TTL field. If
* that reaches zero, we must reply an ICMP control message telling
* that the packet's lifetime expired.
*/
if (ip_hdr(skb)->ttl <= 1)
goto too_many_hops;
if (!xfrm4_route_forward(skb))
goto drop;
rt = skb_rtable(skb);
if (opt->is_strictroute && rt->rt_uses_gateway)
goto sr_failed;
IPCB(skb)->flags |= IPSKB_FORWARDED;
mtu = ip_dst_mtu_maybe_forward(&rt->dst, true);
if (ip_exceeds_mtu(skb, mtu)) {
IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
htonl(mtu));
goto drop;
}
/* We are about to mangle packet. Copy it! */
if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+rt->dst.header_len))
goto drop;
iph = ip_hdr(skb);
/* Decrease ttl after skb cow done */
ip_decrease_ttl(iph);
/*
* We now generate an ICMP HOST REDIRECT giving the route
* we calculated.
*/
if (IPCB(skb)->flags & IPSKB_DOREDIRECT && !opt->srr &&
!skb_sec_path(skb))
ip_rt_send_redirect(skb);
if (net->ipv4.sysctl_ip_fwd_update_priority)
skb->priority = rt_tos2priority(iph->tos);
return NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
net, NULL, skb, skb->dev, rt->dst.dev,
ip_forward_finish);
sr_failed:
/*
* Strict routing permits no gatewaying
*/
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_SR_FAILED, 0);
goto drop;
too_many_hops:
/* Tell the sender its packet died... */
__IP_INC_STATS(net, IPSTATS_MIB_INHDRERRORS);
icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
drop:
kfree_skb(skb);
return NET_RX_DROP;
}