include/net/route.h

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET  is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              Definitions for the IP router.
   7  *
   8  * Version:     @(#)route.h     1.0.4   05/27/93
   9  *
  10  * Authors:     Ross Biro
  11  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12  * Fixes:
  13  *              Alan Cox        :       Reformatted. Added ip_rt_local()
  14  *              Alan Cox        :       Support for TCP parameters.
  15  *              Alexey Kuznetsov:       Major changes for new routing code.
  16  *              Mike McLagan    :       Routing by source
  17  *              Robert Olsson   :       Added rt_cache statistics
  18  *
  19  *              This program is free software; you can redistribute it and/or
  20  *              modify it under the terms of the GNU General Public License
  21  *              as published by the Free Software Foundation; either version
  22  *              2 of the License, or (at your option) any later version.
  23  */
  24 #ifndef _ROUTE_H
  25 #define _ROUTE_H
  26
  27 #include <linux/config.h>
  28 #include <net/dst.h>
  29 #include <net/inetpeer.h>
  30 #include <net/flow.h>
  31 #include <net/inet_sock.h>
  32 #include <linux/in_route.h>
  33 #include <linux/rtnetlink.h>
  34 #include <linux/route.h>
  35 #include <linux/ip.h>
  36 #include <linux/cache.h>
  37 #include <linux/vs_network.h>
  38 #include <linux/in.h>
  39
  40 #ifndef __KERNEL__
  41 #warning This file is not supposed to be used outside of kernel.
  42 #endif
  43
  44 #define RTO_ONLINK      0x01
  45
  46 #define RTO_CONN        0
  47 /* RTO_CONN is not used (being alias for 0), but preserved not to break
  48  * some modules referring to it. */
  49
  50 #define RT_CONN_FLAGS(sk)   (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))
  51
  52 struct fib_nh;
  53 struct inet_peer;
  54 struct rtable
  55 {
  56         union
  57         {
  58                 struct dst_entry        dst;
  59                 struct rtable           *rt_next;
  60         } u;
  61
  62         struct in_device        *idev;
  63
  64         unsigned                rt_flags;
  65         __u16                   rt_type;
  66         __u16                   rt_multipath_alg;
  67
  68         __u32                   rt_dst; /* Path destination     */
  69         __u32                   rt_src; /* Path source          */
  70         int                     rt_iif;
  71
  72         /* Info on neighbour */
  73         __u32                   rt_gateway;
  74
  75         /* Cache lookup keys */
  76         struct flowi            fl;
  77
  78         /* Miscellaneous cached information */
  79         __u32                   rt_spec_dst; /* RFC1122 specific destination */
  80         struct inet_peer        *peer; /* long-living peer info */
  81 };
  82
  83 struct ip_rt_acct
  84 {
  85         __u32   o_bytes;
  86         __u32   o_packets;
  87         __u32   i_bytes;
  88         __u32   i_packets;
  89 };
  90
  91 struct rt_cache_stat
  92 {
  93         unsigned int in_hit;
  94         unsigned int in_slow_tot;
  95         unsigned int in_slow_mc;
  96         unsigned int in_no_route;
  97         unsigned int in_brd;
  98         unsigned int in_martian_dst;
  99         unsigned int in_martian_src;
 100         unsigned int out_hit;
 101         unsigned int out_slow_tot;
 102         unsigned int out_slow_mc;
 103         unsigned int gc_total;
 104         unsigned int gc_ignored;
 105         unsigned int gc_goal_miss;
 106         unsigned int gc_dst_overflow;
 107         unsigned int in_hlist_search;
 108         unsigned int out_hlist_search;
 109 };
 110
 111 extern struct ip_rt_acct *ip_rt_acct;
 112
 113 struct in_device;
 114 extern int              ip_rt_init(void);
 115 extern void             ip_rt_redirect(u32 old_gw, u32 dst, u32 new_gw,
 116                                        u32 src, struct net_device *dev);
 117 extern void             ip_rt_advice(struct rtable **rp, int advice);
 118 extern void             rt_cache_flush(int how);
 119 extern int              __ip_route_output_key(struct rtable **, const struct flowi *flp);
 120 extern int              ip_route_output_key(struct rtable **, struct flowi *flp);
 121 extern int              ip_route_output_flow(struct rtable **rp, struct flowi *flp, struct sock *sk, int flags);
 122 extern int              ip_route_input(struct sk_buff*, u32 dst, u32 src, u8 tos, struct net_device *devin);
 123 extern unsigned short   ip_rt_frag_needed(struct iphdr *iph, unsigned short new_mtu);
 124 extern void             ip_rt_send_redirect(struct sk_buff *skb);
 125
 126 extern unsigned         inet_addr_type(u32 addr);
 127 extern void             ip_rt_multicast_event(struct in_device *);
 128 extern int              ip_rt_ioctl(unsigned int cmd, void __user *arg);
 129 extern void             ip_rt_get_source(u8 *src, struct rtable *rt);
 130 extern int              ip_rt_dump(struct sk_buff *skb,  struct netlink_callback *cb);
 131
 132 struct in_ifaddr;
 133 extern void fib_add_ifaddr(struct in_ifaddr *);
 134
 135 static inline void ip_rt_put(struct rtable * rt)
 136 {
 137         if (rt)
 138                 dst_release(&rt->u.dst);
 139 }
 140
 141 #define IPTOS_RT_MASK   (IPTOS_TOS_MASK & ~3)
 142
 143 extern __u8 ip_tos2prio[16];
 144
 145 static inline char rt_tos2priority(u8 tos)
 146 {
 147         return ip_tos2prio[IPTOS_TOS(tos)>>1];
 148 }
 149
 150 #define IPI_LOOPBACK    htonl(INADDR_LOOPBACK)
 151
 152 static inline int ip_find_src(struct nx_info *nxi, struct rtable **rp, struct flowi *fl)
 153 {
 154         int err;
 155         int i, n = nxi->nbipv4;
 156         u32 ipv4root = nxi->ipv4[0];
 157
 158         if (ipv4root == 0)
 159                 return 0;
 160
 161         if (fl->fl4_src == 0) {
 162                 if (n > 1) {
 163                         u32 foundsrc;
 164
 165                         err = __ip_route_output_key(rp, fl);
 166                         if (err) {
 167                                 fl->fl4_src = ipv4root;
 168                                 err = __ip_route_output_key(rp, fl);
 169                         }
 170                         if (err)
 171                                 return err;
 172
 173                         foundsrc = (*rp)->rt_src;
 174                         ip_rt_put(*rp);
 175
 176                         for (i=0; i<n; i++){
 177                                 u32 mask = nxi->mask[i];
 178                                 u32 ipv4 = nxi->ipv4[i];
 179                                 u32 net4 = ipv4 & mask;
 180
 181                                 if (foundsrc == ipv4) {
 182                                         fl->fl4_src = ipv4;
 183                                         break;
 184                                 }
 185                                 if (!fl->fl4_src && (foundsrc & mask) == net4)
 186                                         fl->fl4_src = ipv4;
 187                         }
 188                 }
 189                 if (fl->fl4_src == 0)
 190                         fl->fl4_src = (fl->fl4_dst == IPI_LOOPBACK)
 191                                 ? IPI_LOOPBACK : ipv4root;
 192         } else {
 193                 for (i=0; i<n; i++) {
 194                         if (nxi->ipv4[i] == fl->fl4_src)
 195                                 break;
 196                 }
 197                 if (i == n)
 198                         return -EPERM;
 199         }
 200         return 0;
 201 }
 202
 203 static inline int ip_route_connect(struct rtable **rp, u32 dst,
 204                                    u32 src, u32 tos, int oif, u8 protocol,
 205                                    u16 sport, u16 dport, struct sock *sk)
 206 {
 207         struct flowi fl = { .oif = oif,
 208                             .nl_u = { .ip4_u = { .daddr = dst,
 209                                                  .saddr = src,
 210                                                  .tos   = tos } },
 211                             .proto = protocol,
 212                             .uli_u = { .ports =
 213                                        { .sport = sport,
 214                                          .dport = dport } } };
 215
 216         int err;
 217         struct nx_info *nx_info = current->nx_info;
 218
 219         if (sk)
 220                 nx_info = sk->sk_nx_info;
 221         vxdprintk(VXD_CBIT(net, 4),
 222                 "ip_route_connect(%p) %p,%p;%lx",
 223                 sk, nx_info, sk->sk_socket,
 224                 (sk->sk_socket?sk->sk_socket->flags:0));
 225
 226         if (nx_info) {
 227                 err = ip_find_src(nx_info, rp, &fl);
 228                 if (err)
 229                         return err;
 230                 if (fl.fl4_dst == IPI_LOOPBACK && !vx_check(0, VX_ADMIN))
 231                         fl.fl4_dst = nx_info->ipv4[0];
 232 #ifdef CONFIG_VSERVER_REMAP_SADDR
 233                 if (fl.fl4_src == IPI_LOOPBACK && !vx_check(0, VX_ADMIN))
 234                         fl.fl4_src = nx_info->ipv4[0];
 235 #endif
 236         }
 237         if (!fl.fl4_dst || !fl.fl4_src) {
 238                 err = __ip_route_output_key(rp, &fl);
 239                 if (err)
 240                         return err;
 241                 fl.fl4_dst = (*rp)->rt_dst;
 242                 fl.fl4_src = (*rp)->rt_src;
 243                 ip_rt_put(*rp);
 244                 *rp = NULL;
 245         }
 246         return ip_route_output_flow(rp, &fl, sk, 0);
 247 }
 248
 249 static inline int ip_route_newports(struct rtable **rp, u8 protocol,
 250                                     u16 sport, u16 dport, struct sock *sk)
 251 {
 252         if (sport != (*rp)->fl.fl_ip_sport ||
 253             dport != (*rp)->fl.fl_ip_dport) {
 254                 struct flowi fl;
 255
 256                 memcpy(&fl, &(*rp)->fl, sizeof(fl));
 257                 fl.fl_ip_sport = sport;
 258                 fl.fl_ip_dport = dport;
 259                 fl.proto = protocol;
 260                 ip_rt_put(*rp);
 261                 *rp = NULL;
 262                 return ip_route_output_flow(rp, &fl, sk, 0);
 263         }
 264         return 0;
 265 }
 266
 267 extern void rt_bind_peer(struct rtable *rt, int create);
 268
 269 static inline struct inet_peer *rt_get_peer(struct rtable *rt)
 270 {
 271         if (rt->peer)
 272                 return rt->peer;
 273
 274         rt_bind_peer(rt, 0);
 275         return rt->peer;
 276 }
 277
 278 extern ctl_table ipv4_route_table[];
 279
 280 #endif  /* _ROUTE_H */