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Release 4.14 net/ipv4/netfilter.c

Directory: net/ipv4
 * 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 sk_buff *skb, unsigned int addr_type) { const struct iphdr *iph = ip_hdr(skb); struct rtable *rt; struct flowi4 fl4 = {}; __be32 saddr = iph->saddr; const struct sock *sk = skb_to_full_sk(skb); __u8 flags = sk ? inet_sk_flowi_flags(sk) : 0; struct net_device *dev = skb_dst(skb)->dev; unsigned int hh_len; 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; 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; }


Harald Welte11128.76%14.17%
Patrick McHardy5915.28%312.50%
David S. Miller4110.62%312.50%
Eric Dumazet389.84%28.33%
Julian Anastasov389.84%28.33%
David Ahern318.03%14.17%
Herbert Xu235.96%28.33%
Simon Horman133.37%14.17%
Florian Westphal112.85%14.17%
Eric W. Biedermann51.30%14.17%
Arnaldo Carvalho de Melo41.04%14.17%
Paul Guo30.78%14.17%
KOVACS Krisztian30.78%14.17%
Alexey Dobriyan30.78%28.33%
Denis V. Lunev20.52%14.17%
Thomas Graf10.26%14.17%

EXPORT_SYMBOL(ip_route_me_harder); /* * Extra routing may needed on local out, as the QUEUE target never * returns control to the table. */ struct ip_rt_info { __be32 daddr; __be32 saddr; u_int8_t tos; u_int32_t mark; };
static void nf_ip_saveroute(const struct sk_buff *skb, struct nf_queue_entry *entry) { struct ip_rt_info *rt_info = nf_queue_entry_reroute(entry); if (entry->state.hook == NF_INET_LOCAL_OUT) { const struct iphdr *iph = ip_hdr(skb); rt_info->tos = iph->tos; rt_info->daddr = iph->daddr; rt_info->saddr = iph->saddr; rt_info->mark = skb->mark; } }


Harald Welte6275.61%114.29%
Eric Leblond89.76%114.29%
Patrick McHardy78.54%342.86%
Arnaldo Carvalho de Melo33.66%114.29%
David S. Miller22.44%114.29%

static int nf_ip_reroute(struct net *net, struct sk_buff *skb, const struct nf_queue_entry *entry) { const struct ip_rt_info *rt_info = nf_queue_entry_reroute(entry); if (entry->state.hook == NF_INET_LOCAL_OUT) { const struct iphdr *iph = ip_hdr(skb); if (!(iph->tos == rt_info->tos && skb->mark == rt_info->mark && iph->daddr == rt_info->daddr && iph->saddr == rt_info->saddr)) return ip_route_me_harder(net, skb, RTN_UNSPEC); } return 0; }


Harald Welte7368.87%19.09%
Eric Leblond87.55%19.09%
Patrick McHardy76.60%327.27%
Eric W. Biedermann76.60%218.18%
Arnaldo Carvalho de Melo43.77%19.09%
Herbert Xu32.83%19.09%
David S. Miller21.89%19.09%
Simon Horman21.89%19.09%

__sum16 nf_ip_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, u_int8_t protocol) { const struct iphdr *iph = ip_hdr(skb); __sum16 csum = 0; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN) break; if ((protocol == 0 && !csum_fold(skb->csum)) || !csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len - dataoff, protocol, skb->csum)) { skb->ip_summed = CHECKSUM_UNNECESSARY; break; } /* fall through */ case CHECKSUM_NONE: if (protocol == 0) skb->csum = 0; else skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, skb->len - dataoff, protocol, 0); csum = __skb_checksum_complete(skb); } return csum; }


Patrick McHardy15496.25%360.00%
Arnaldo Carvalho de Melo42.50%120.00%
Al Viro21.25%120.00%

static __sum16 nf_ip_checksum_partial(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, unsigned int len, u_int8_t protocol) { const struct iphdr *iph = ip_hdr(skb); __sum16 csum = 0; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: if (len == skb->len - dataoff) return nf_ip_checksum(skb, hook, dataoff, protocol); /* fall through */ case CHECKSUM_NONE: skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, protocol, skb->len - dataoff, 0); skb->ip_summed = CHECKSUM_NONE; return __skb_checksum_complete_head(skb, dataoff + len); } return csum; }


Patrick McHardy12198.37%150.00%
Shan Wei21.63%150.00%

static 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; }


David S. Miller3450.75%233.33%
Patrick McHardy2232.84%116.67%
Florian Westphal1014.93%233.33%
Denis V. Lunev11.49%116.67%

static const struct nf_afinfo nf_ip_afinfo = { .family = AF_INET, .checksum = nf_ip_checksum, .checksum_partial = nf_ip_checksum_partial, .route = nf_ip_route, .saveroute = nf_ip_saveroute, .reroute = nf_ip_reroute, .route_key_size = sizeof(struct ip_rt_info), };
static int __init ipv4_netfilter_init(void) { return nf_register_afinfo(&nf_ip_afinfo); }


Harald Welte1275.00%125.00%
Patrick McHardy212.50%125.00%
Jan Beulich16.25%125.00%
Andrew Morton16.25%125.00%


Overall Contributors

Patrick McHardy42039.81%1327.08%
Harald Welte30929.29%24.17%
David S. Miller797.49%48.33%
Eric Dumazet383.60%24.17%
Julian Anastasov383.60%24.17%
David Ahern312.94%12.08%
Herbert Xu292.75%24.17%
Florian Westphal211.99%36.25%
Eric Leblond191.80%12.08%
Simon Horman151.42%12.08%
Arnaldo Carvalho de Melo151.42%12.08%
Eric W. Biedermann121.14%24.17%
Al Viro40.38%24.17%
Paul Gortmaker40.38%24.17%
KOVACS Krisztian30.28%12.08%
Paul Guo30.28%12.08%
Alexey Dobriyan30.28%24.17%
Tejun Heo30.28%12.08%
Denis V. Lunev30.28%12.08%
Shan Wei20.19%12.08%
Andrew Morton20.19%12.08%
Thomas Graf10.09%12.08%
Jan Beulich10.09%12.08%
Directory: net/ipv4
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