path: root/include/net/ip_vs.h

/* IP Virtual Server
 * data structure and functionality definitions
 */

#ifndef _NET_IP_VS_H
#define _NET_IP_VS_H

#include <linux/ip_vs.h>                /* definitions shared with userland */

#include <asm/types.h>                  /* for __uXX types */

#include <linux/list.h>                 /* for struct list_head */
#include <linux/spinlock.h>             /* for struct rwlock_t */
#include <linux/atomic.h>               /* for struct atomic_t */
#include <linux/compiler.h>
#include <linux/timer.h>
#include <linux/bug.h>

#include <net/checksum.h>
#include <linux/netfilter.h>		/* for union nf_inet_addr */
#include <linux/ip.h>
#include <linux/ipv6.h>			/* for struct ipv6hdr */
#include <net/ipv6.h>
#if IS_ENABLED(CONFIG_IP_VS_IPV6)
#include <linux/netfilter_ipv6/ip6_tables.h>
#endif
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
#include <net/netfilter/nf_conntrack.h>
#endif
#include <net/net_namespace.h>		/* Netw namespace */

/* Generic access of ipvs struct */
static inline struct netns_ipvs *net_ipvs(struct net* net)
{
	return net->ipvs;
}

/* Get net ptr from skb in traffic cases
 * use skb_sknet when call is from userland (ioctl or netlink)
 */
static inline struct net *skb_net(const struct sk_buff *skb)
{
#ifdef CONFIG_NET_NS
#ifdef CONFIG_IP_VS_DEBUG
	/*
	 * This is used for debug only.
	 * Start with the most likely hit
	 * End with BUG
	 */
	if (likely(skb->dev && dev_net(skb->dev)))
		return dev_net(skb->dev);
	if (skb_dst(skb) && skb_dst(skb)->dev)
		return dev_net(skb_dst(skb)->dev);
	WARN(skb->sk, "Maybe skb_sknet should be used in %s() at line:%d\n",
		      __func__, __LINE__);
	if (likely(skb->sk && sock_net(skb->sk)))
		return sock_net(skb->sk);
	pr_err("There is no net ptr to find in the skb in %s() line:%d\n",
		__func__, __LINE__);
	BUG();
#else
	return dev_net(skb->dev ? : skb_dst(skb)->dev);
#endif
#else
	return &init_net;
#endif
}

static inline struct net *skb_sknet(const struct sk_buff *skb)
{
#ifdef CONFIG_NET_NS
#ifdef CONFIG_IP_VS_DEBUG
	/* Start with the most likely hit */
	if (likely(skb->sk && sock_net(skb->sk)))
		return sock_net(skb->sk);
	WARN(skb->dev, "Maybe skb_net should be used instead in %s() line:%d\n",
		       __func__, __LINE__);
	if (likely(skb->dev && dev_net(skb->dev)))
		return dev_net(skb->dev);
	pr_err("There is no net ptr to find in the skb in %s() line:%d\n",
		__func__, __LINE__);
	BUG();
#else
	return sock_net(skb->sk);
#endif
#else
	return &init_net;
#endif
}

/* This one needed for single_open_net since net is stored directly in
 * private not as a struct i.e. seq_file_net can't be used.
 */
static inline struct net *seq_file_single_net(struct seq_file *seq)
{
#ifdef CONFIG_NET_NS
	return (struct net *)seq->private;
#else
	return &init_net;
#endif
}

/* Connections' size value needed by ip_vs_ctl.c */
extern int ip_vs_conn_tab_size;

struct ip_vs_iphdr {
	__u32 len;	/* IPv4 simply where L4 starts
			 * IPv6 where L4 Transport Header starts */
	__u16 fragoffs; /* IPv6 fragment offset, 0 if first frag (or not frag)*/
	__s16 protocol;
	__s32 flags;
	union nf_inet_addr saddr;
	union nf_inet_addr daddr;
};

static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset,
				      int len, void *buffer,
				      const struct ip_vs_iphdr *ipvsh)
{
	return skb_header_pointer(skb, offset, len, buffer);
}

static inline void
ip_vs_fill_ip4hdr(const void *nh, struct ip_vs_iphdr *iphdr)
{
	const struct iphdr *iph = nh;

	iphdr->len	= iph->ihl * 4;
	iphdr->fragoffs	= 0;
	iphdr->protocol	= iph->protocol;
	iphdr->saddr.ip	= iph->saddr;
	iphdr->daddr.ip	= iph->daddr;
}

/* This function handles filling *ip_vs_iphdr, both for IPv4 and IPv6.
 * IPv6 requires some extra work, as finding proper header position,
 * depend on the IPv6 extension headers.
 */
static inline void
ip_vs_fill_iph_skb(int af, const struct sk_buff *skb, struct ip_vs_iphdr *iphdr)
{
#ifdef CONFIG_IP_VS_IPV6
	if (af == AF_INET6) {
		const struct ipv6hdr *iph =
			(struct ipv6hdr *)skb_network_header(skb);
		iphdr->saddr.in6 = iph->saddr;
		iphdr->daddr.in6 = iph->daddr;
		/* ipv6_find_hdr() updates len, flags */
		iphdr->len	 = 0;
		iphdr->flags	 = 0;
		iphdr->protocol  = ipv6_find_hdr(skb, &iphdr->len, -1,
						 &iphdr->fragoffs,
						 &iphdr->flags);
	} else
#endif
	{
		const struct iphdr *iph =
			(struct iphdr *)skb_network_header(skb);
		iphdr->len	= iph->ihl * 4;
		iphdr->fragoffs	= 0;
		iphdr->protocol	= iph->protocol;
		iphdr->saddr.ip	= iph->saddr;
		iphdr->daddr.ip	= iph->daddr;
	}
}

static inline void ip_vs_addr_copy(int af, union nf_inet_addr *dst,
				   const u