route.h

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/*
 * 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.
 *
 *              Definitions for the IP router.
 *
 * Version:     @(#)route.h     1.0.4   05/27/93
 *
 * Authors:     Ross Biro, <bir7@leland.Stanford.Edu>
 *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 * Fixes:
 *              Alan Cox        :       Reformatted. Added ip_rt_local()
 *              Alan Cox        :       Support for TCP parameters.
 *              Alexey Kuznetsov:       Major changes for new routing code.
 *              Mike McLagan    :       Routing by source
 *              Robert Olsson   :       Added rt_cache statistics
 *
 *              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.
 */
#ifndef _ROUTE_H
#define _ROUTE_H

#include <linux/config.h>
#include <net/dst.h>
#include <net/inetpeer.h>
#include <linux/in_route.h>
#include <linux/rtnetlink.h>
#include <linux/route.h>
#include <linux/ip.h>
#include <linux/cache.h>

#ifndef __KERNEL__
#warning This file is not supposed to be used outside of kernel.
#endif

#define RTO_ONLINK      0x01

#define RTO_CONN        0
/* RTO_CONN is not used (being alias for 0), but preserved not to break
 * some modules referring to it. */

#define RT_CONN_FLAGS(sk)   (RT_TOS(sk->protinfo.af_inet.tos) | sk->localroute)

struct rt_key
{
        __u32                   dst;
        __u32                   src;
        int                     iif;
        int                     oif;
#ifdef CONFIG_IP_ROUTE_FWMARK
        __u32                   fwmark;
#endif
        __u8                    tos;
        __u8                    scope;
};

struct inet_peer;
struct rtable
{
        union
        {
                struct dst_entry        dst;
                struct rtable           *rt_next;
        } u;

        unsigned                rt_flags;
        unsigned                rt_type;

        __u32                   rt_dst; /* Path destination     */
        __u32                   rt_src; /* Path source          */
        int                     rt_iif;

        /* Info on neighbour */
        __u32                   rt_gateway;

        /* Cache lookup keys */
        struct rt_key           key;

        /* Miscellaneous cached information */
        __u32                   rt_spec_dst; /* RFC1122 specific destination */
        struct inet_peer        *peer; /* long-living peer info */

#ifdef CONFIG_IP_ROUTE_NAT
        __u32                   rt_src_map;
        __u32                   rt_dst_map;
#endif
};

struct ip_rt_acct
{
        __u32   o_bytes;
        __u32   o_packets;
        __u32   i_bytes;
        __u32   i_packets;
};

struct rt_cache_stat 
{
        unsigned int in_hit;
        unsigned int in_slow_tot;
        unsigned int in_slow_mc;
        unsigned int in_no_route;
        unsigned int in_brd;
        unsigned int in_martian_dst;
        unsigned int in_martian_src;
        unsigned int out_hit;
        unsigned int out_slow_tot;
        unsigned int out_slow_mc;
        unsigned int gc_total;
        unsigned int gc_ignored;
        unsigned int gc_goal_miss;
        unsigned int gc_dst_overflow;
        unsigned int in_hlist_search;
        unsigned int out_hlist_search;
} ____cacheline_aligned_in_smp;

extern struct ip_rt_acct *ip_rt_acct;

struct in_device;
extern void             ip_rt_init(void);
extern void             ip_rt_redirect(u32 old_gw, u32 dst, u32 new_gw,
                                       u32 src, u8 tos, struct net_device *dev);
extern void             ip_rt_advice(struct rtable **rp, int advice);
extern void             rt_cache_flush(int how);
extern int              ip_route_output_key(struct rtable **, const struct rt_key *key);
extern int              ip_route_input(struct sk_buff*, u32 dst, u32 src, u8 tos, struct net_device *devin);
extern unsigned short   ip_rt_frag_needed(struct iphdr *iph, unsigned short new_mtu);
extern void             ip_rt_update_pmtu(struct dst_entry *dst, unsigned mtu);
extern void             ip_rt_send_redirect(struct sk_buff *skb);

extern unsigned         inet_addr_type(u32 addr);
extern void             ip_rt_multicast_event(struct in_device *);
extern int              ip_rt_ioctl(unsigned int cmd, void *arg);
extern void             ip_rt_get_source(u8 *src, struct rtable *rt);
extern int              ip_rt_dump(struct sk_buff *skb,  struct netlink_callback *cb);

/* Deprecated: use ip_route_output_key directly */
static inline int ip_route_output(struct rtable **rp,
                                      u32 daddr, u32 saddr, u32 tos, int oif)
{
        struct rt_key key = { dst:daddr, src:saddr, oif:oif, tos:tos };

        return ip_route_output_key(rp, &key);
}


static inline void ip_rt_put(struct rtable * rt)
{
        if (rt)
                dst_release(&rt->u.dst);
}

#define IPTOS_RT_MASK   (IPTOS_TOS_MASK & ~3)

extern __u8 ip_tos2prio[16];

static inline char rt_tos2priority(u8 tos)
{
        return ip_tos2prio[IPTOS_TOS(tos)>>1];
}

static inline int ip_route_connect(struct rtable **rp, u32 dst, u32 src, u32 tos, int oif)
{
        int err;
        err = ip_route_output(rp, dst, src, tos, oif);
        if (err || (dst && src))
                return err;
        dst = (*rp)->rt_dst;
        src = (*rp)->rt_src;
        ip_rt_put(*rp);
        *rp = NULL;
        return ip_route_output(rp, dst, src, tos, oif);
}

extern void rt_bind_peer(struct rtable *rt, int create);

static inline struct inet_peer *rt_get_peer(struct rtable *rt)
{
        if (rt->peer)
                return rt->peer;

        rt_bind_peer(rt, 0);
        return rt->peer;
}

#endif  /* _ROUTE_H */

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