route.c

   1 /* route
   2  *
   3  * Similar to the standard Unix route, but with only the necessary
   4  * parts for AF_INET
   5  *
   6  * Bjorn Wesen, Axis Communications AB
   7  *
   8  * Author of the original route:
   9  *              Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
  10  *              (derived from FvK's 'route.c     1.70    01/04/94')
  11  *
  12  * This program is free software; you can redistribute it
  13  * and/or  modify it under  the terms of  the GNU General
  14  * Public  License as  published  by  the  Free  Software
  15  * Foundation;  either  version 2 of the License, or  (at
  16  * your option) any later version.
  17  *
  18  * $Id: route.c,v 1.10 2001/03/21 07:34:26 andersen Exp $
  19  *
  20  * displayroute() code added by Vladimir N. Oleynik <dzo@simtreas.ru>
  21  * adjustments by Larry Doolittle  <LRDoolittle@lbl.gov>
  22  */
  23
  24 #include <sys/types.h>
  25 #include <sys/ioctl.h>
  26 #include <sys/socket.h>
  27 #include <net/route.h>
  28 #include <linux/param.h>  // HZ
  29 #include <netinet/in.h>
  30 #include <arpa/inet.h>
  31 #include <stdio.h>
  32 #include <errno.h>
  33 #include <fcntl.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <getopt.h>
  37 #include <unistd.h>
  38 #include <ctype.h>
  39 #include "busybox.h"
  40
  41 #define _(x) x
  42
  43 #define RTACTION_ADD   1
  44 #define RTACTION_DEL   2
  45 #define RTACTION_HELP  3
  46 #define RTACTION_FLUSH 4
  47 #define RTACTION_SHOW  5
  48
  49 #define E_NOTFOUND      8
  50 #define E_SOCK          7
  51 #define E_LOOKUP        6
  52 #define E_VERSION       5
  53 #define E_USAGE         4
  54 #define E_OPTERR        3
  55 #define E_INTERN        2
  56 #define E_NOSUPP        1
  57
  58 /* resolve XXX.YYY.ZZZ.QQQ -> binary */
  59
  60 static int
  61 INET_resolve(char *name, struct sockaddr *sa)
  62 {
  63         struct sockaddr_in *s_in = (struct sockaddr_in *)sa;
  64
  65         s_in->sin_family = AF_INET;
  66         s_in->sin_port = 0;
  67
  68         /* Default is special, meaning 0.0.0.0. */
  69         if (strcmp(name, "default")==0) {
  70                 s_in->sin_addr.s_addr = INADDR_ANY;
  71                 return 1;
  72         }
  73         /* Look to see if it's a dotted quad. */
  74         if (inet_aton(name, &s_in->sin_addr)) {
  75                 return 0;
  76         }
  77         /* guess not.. */
  78         return -1;
  79 }
  80
  81 #if defined (SIOCADDRTOLD) || defined (RTF_IRTT)        /* route */
  82 #define HAVE_NEW_ADDRT 1
  83 #endif
  84 #ifdef RTF_IRTT                 /* route */
  85 #define HAVE_RTF_IRTT 1
  86 #endif
  87 #ifdef RTF_REJECT               /* route */
  88 #define HAVE_RTF_REJECT 1
  89 #endif
  90
  91 #if HAVE_NEW_ADDRT
  92 #define mask_in_addr(x) (((struct sockaddr_in *)&((x).rt_genmask))->sin_addr.s_addr)
  93 #define full_mask(x) (x)
  94 #else
  95 #define mask_in_addr(x) ((x).rt_genmask)
  96 #define full_mask(x) (((struct sockaddr_in *)&(x))->sin_addr.s_addr)
  97 #endif
  98
  99 /* add or delete a route depending on action */
 100
 101 static int
 102 INET_setroute(int action, int options, char **args)
 103 {
 104         struct rtentry rt;
 105         char target[128], gateway[128] = "NONE", netmask[128] = "default";
 106         int xflag, isnet;
 107         int skfd;
 108
 109         xflag = 0;
 110
 111         if (strcmp(*args, "-net")==0) {
 112                 xflag = 1;
 113                 args++;
 114         } else if (strcmp(*args, "-host")==0) {
 115                 xflag = 2;
 116                 args++;
 117         }
 118         if (*args == NULL)
 119                 show_usage();
 120
 121         safe_strncpy(target, *args++, (sizeof target));
 122
 123         /* Clean out the RTREQ structure. */
 124         memset((char *) &rt, 0, sizeof(struct rtentry));
 125
 126
 127         if ((isnet = INET_resolve(target, &rt.rt_dst)) < 0) {
 128                 error_msg(_("can't resolve %s"), target);
 129                 return EXIT_FAILURE;   /* XXX change to E_something */
 130         }
 131
 132         switch (xflag) {
 133                 case 1:
 134                         isnet = 1;
 135                         break;
 136
 137                 case 2:
 138                         isnet = 0;
 139                         break;
 140
 141                 default:
 142                         break;
 143         }
 144
 145         /* Fill in the other fields. */
 146         rt.rt_flags = (RTF_UP | RTF_HOST);
 147         if (isnet)
 148                 rt.rt_flags &= ~RTF_HOST;
 149
 150         while (*args) {
 151                 if (strcmp(*args, "metric")==0) {
 152                         int metric;
 153
 154                         args++;
 155                         if (!*args || !isdigit(**args))
 156                                 show_usage();
 157                         metric = atoi(*args);
 158 #if HAVE_NEW_ADDRT
 159                         rt.rt_metric = metric + 1;
 160 #else
 161                         ENOSUPP("inet_setroute", "NEW_ADDRT (metric)");  /* XXX Fixme */
 162 #endif
 163                         args++;
 164                         continue;
 165                 }
 166
 167                 if (strcmp(*args, "netmask")==0) {
 168                         struct sockaddr mask;
 169
 170                         args++;
 171                         if (!*args || mask_in_addr(rt))
 172                                 show_usage();
 173                         safe_strncpy(netmask, *args, (sizeof netmask));
 174                         if ((isnet = INET_resolve(netmask, &mask)) < 0) {
 175                                 error_msg(_("can't resolve netmask %s"), netmask);
 176                                 return E_LOOKUP;
 177                         }
 178                         rt.rt_genmask = full_mask(mask);
 179                         args++;
 180                         continue;
 181                 }
 182
 183                 if (strcmp(*args, "gw")==0 || strcmp(*args, "gateway")==0) {
 184                         args++;
 185                         if (!*args)
 186                                 show_usage();
 187                         if (rt.rt_flags & RTF_GATEWAY)
 188                                 show_usage();
 189                         safe_strncpy(gateway, *args, (sizeof gateway));
 190                         if ((isnet = INET_resolve(gateway, &rt.rt_gateway)) < 0) {
 191                                 error_msg(_("can't resolve gw %s"), gateway);
 192                                 return E_LOOKUP;
 193                         }
 194                         if (isnet) {
 195                                 error_msg(
 196                                         _("%s: cannot use a NETWORK as gateway!"),
 197                                         gateway);
 198                                 return E_OPTERR;
 199                         }
 200                         rt.rt_flags |= RTF_GATEWAY;
 201                         args++;
 202                         continue;
 203                 }
 204
 205                 if (strcmp(*args, "mss")==0) {
 206                         args++;
 207                         rt.rt_flags |= RTF_MSS;
 208                         if (!*args)
 209                                 show_usage();
 210                         rt.rt_mss = atoi(*args);
 211                         args++;
 212                         if (rt.rt_mss < 64 || rt.rt_mss > 32768) {
 213                                 error_msg(_("Invalid MSS."));
 214                                 return E_OPTERR;
 215                         }
 216                         continue;
 217                 }
 218
 219                 if (strcmp(*args, "window")==0) {
 220                         args++;
 221                         if (!*args)
 222                                 show_usage();
 223                         rt.rt_flags |= RTF_WINDOW;
 224                         rt.rt_window = atoi(*args);
 225                         args++;
 226                         if (rt.rt_window < 128) {
 227                                 error_msg(_("Invalid window."));
 228                                 return E_OPTERR;
 229                         }
 230                         continue;
 231                 }
 232
 233                 if (strcmp(*args, "irtt")==0) {
 234                         args++;
 235                         if (!*args)
 236                                 show_usage();
 237                         args++;
 238 #if HAVE_RTF_IRTT
 239                         rt.rt_flags |= RTF_IRTT;
 240                         rt.rt_irtt = atoi(*(args - 1));
 241                         rt.rt_irtt *= (HZ / 100);       /* FIXME */
 242 #if 0                           /* FIXME: do we need to check anything of this? */
 243                         if (rt.rt_irtt < 1 || rt.rt_irtt > (120 * HZ)) {
 244                                 error_msg(_("Invalid initial rtt."));
 245                                 return E_OPTERR;
 246                         }
 247 #endif
 248 #else
 249                         ENOSUPP("inet_setroute", "RTF_IRTT"); /* XXX Fixme */
 250 #endif
 251                         continue;
 252                 }
 253
 254                 if (strcmp(*args, "reject")==0) {
 255                         args++;
 256 #if HAVE_RTF_REJECT
 257                         rt.rt_flags |= RTF_REJECT;
 258 #else
 259                         ENOSUPP("inet_setroute", "RTF_REJECT"); /* XXX Fixme */
 260 #endif
 261                         continue;
 262                 }
 263                 if (strcmp(*args, "mod")==0) {
 264                         args++;
 265                         rt.rt_flags |= RTF_MODIFIED;
 266                         continue;
 267                 }
 268                 if (strcmp(*args, "dyn")==0) {
 269                         args++;
 270                         rt.rt_flags |= RTF_DYNAMIC;
 271                         continue;
 272                 }
 273                 if (strcmp(*args, "reinstate")==0) {
 274                         args++;
 275                         rt.rt_flags |= RTF_REINSTATE;
 276                         continue;
 277                 }
 278                 if (strcmp(*args, "device")==0 || strcmp(*args, "dev")==0) {
 279                         args++;
 280                         if (rt.rt_dev || *args == NULL)
 281                                 show_usage();
 282                         rt.rt_dev = *args++;
 283                         continue;
 284                 }
 285                 /* nothing matches */
 286                 if (!rt.rt_dev) {
 287                         rt.rt_dev = *args++;
 288                         if (*args)
 289                                 show_usage();   /* must be last to catch typos */
 290                 } else {
 291                         show_usage();
 292                 }
 293         }
 294
 295 #if HAVE_RTF_REJECT
 296         if ((rt.rt_flags & RTF_REJECT) && !rt.rt_dev)
 297                 rt.rt_dev = "lo";
 298 #endif
 299
 300         /* sanity checks.. */
 301         if (mask_in_addr(rt)) {
 302                 unsigned long mask = mask_in_addr(rt);
 303                 mask = ~ntohl(mask);
 304                 if ((rt.rt_flags & RTF_HOST) && mask != 0xffffffff) {
 305                         error_msg(
 306                                 _("netmask %.8x doesn't make sense with host route"),
 307                                 (unsigned int)mask);
 308                         return E_OPTERR;
 309                 }
 310                 if (mask & (mask + 1)) {
 311                         error_msg(_("bogus netmask %s"), netmask);
 312                         return E_OPTERR;
 313                 }
 314                 mask = ((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr;
 315                 if (mask & ~mask_in_addr(rt)) {
 316                         error_msg(_("netmask doesn't match route address"));
 317                         return E_OPTERR;
 318                 }
 319         }
 320         /* Fill out netmask if still unset */
 321         if ((action == RTACTION_ADD) && rt.rt_flags & RTF_HOST)
 322                 mask_in_addr(rt) = 0xffffffff;
 323
 324         /* Create a socket to the INET kernel. */
 325         if ((skfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
 326                 perror("socket");
 327                 return E_SOCK;
 328         }
 329         /* Tell the kernel to accept this route. */
 330         if (action == RTACTION_DEL) {
 331                 if (ioctl(skfd, SIOCDELRT, &rt) < 0) {
 332                         perror("SIOCDELRT");
 333                         close(skfd);
 334                         return E_SOCK;
 335                 }
 336         } else {
 337                 if (ioctl(skfd, SIOCADDRT, &rt) < 0) {
 338                         perror("SIOCADDRT");
 339                         close(skfd);
 340                         return E_SOCK;
 341                 }
 342         }
 343
 344         /* Close the socket. */
 345         (void) close(skfd);
 346         return EXIT_SUCCESS;
 347 }
 348
 349 static void displayroutes(void)
 350 {
 351         char buff[256];
 352         int  nl = 0 ;
 353         struct in_addr dest;
 354         struct in_addr gw;
 355         struct in_addr mask;
 356         int flgs, ref, use, metric;
 357         char flags[4];
 358         unsigned long int d,g,m;
 359
 360         char sdest[16], sgw[16];
 361
 362
 363         FILE *fp = xfopen("/proc/net/route", "r");
 364
 365         while( fgets(buff, sizeof(buff), fp) != NULL ) {
 366                 if(nl) {
 367                         int ifl = 0;
 368                         while(buff[ifl]!=' ' && buff[ifl]!='\t' && buff[ifl]!='\0')
 369                                 ifl++;
 370                         buff[ifl]=0;    /* interface */
 371                         if(sscanf(buff+ifl+1, "%lx%lx%d%d%d%d%lx",
 372                            &d, &g, &flgs, &ref, &use, &metric, &m)!=7) {
 373                                 error_msg_and_die( "Unsuported kernel route format\n");
 374                         }
 375                         if(nl==1) {
 376                 printf("Kernel IP routing table\n"
 377 "Destination     Gateway         Genmask         Flags Metric Ref    Use Iface\n");
 378                         }
 379
 380
 381                         ifl = 0;        /* parse flags */
 382                         if(flgs&1)
 383                                 flags[ifl++]='U';
 384                         if(flgs&2)
 385                                 flags[ifl++]='G';
 386                         if(flgs&4)
 387                                 flags[ifl++]='H';
 388                         flags[ifl]=0;
 389                         dest.s_addr = d;
 390                         gw.s_addr   = g;
 391                         mask.s_addr = m;
 392                         strcpy(sdest,  (dest.s_addr==0 ? "default" :
 393                                         inet_ntoa(dest)));
 394                         strcpy(sgw,    (gw.s_addr==0   ? "*"       :
 395                                         inet_ntoa(gw)));
 396                         printf("%-16s%-16s%-16s%-6s%-6d %-2d %7d %s\n",
 397                                 sdest, sgw,
 398                                 inet_ntoa(mask),
 399                                 flags, metric, ref, use, buff);
 400                 }
 401         nl++;
 402         }
 403 }
 404
 405 int route_main(int argc, char **argv)
 406 {
 407         int what = 0;
 408
 409         argc--;
 410         argv++;
 411
 412         if (*argv == NULL) {
 413                 displayroutes();
 414                 return EXIT_SUCCESS;
 415         } else {
 416                 /* check verb */
 417                 if (strcmp(*argv, "add")==0)
 418                         what = RTACTION_ADD;
 419                 else if (strcmp(*argv, "del")==0 || strcmp(*argv, "delete")==0)
 420                         what = RTACTION_DEL;
 421                 else if (strcmp(*argv, "flush")==0)
 422                         what = RTACTION_FLUSH;
 423                 else
 424                         show_usage();
 425         }
 426
 427         return INET_setroute(what, 0, ++argv);
 428 }