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