networking/ifupdown.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  *  ifupdown for busybox
   4  *  Copyright (c) 2002 Glenn McGrath <bug1@iinet.net.au>
   5  *  Copyright (c) 2003-2004 Erik Andersen <andersen@codepoet.org>
   6  *
   7  *  Based on ifupdown v 0.6.4 by Anthony Towns
   8  *  Copyright (c) 1999 Anthony Towns <aj@azure.humbug.org.au>
   9  *
  10  *  Changes to upstream version
  11  *  Remove checks for kernel version, assume kernel version 2.2.0 or better.
  12  *  Lines in the interfaces file cannot wrap.
  13  *  To adhere to the FHS, the default state file is /var/run/ifstate.
  14  *
  15  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  16  */
  17
  18 /* TODO: standardise execute() return codes to return 0 for success and 1 for failure */
  19
  20 #include <sys/stat.h>
  21 #include <sys/utsname.h>
  22 #include <sys/wait.h>
  23
  24 #include <ctype.h>
  25 #include <errno.h>
  26 #include <fcntl.h>
  27 #include <fnmatch.h>
  28 #include <getopt.h>
  29 #include <stdarg.h>
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <unistd.h>
  34
  35 #include "busybox.h"
  36
  37 #define MAX_OPT_DEPTH 10
  38 #define EUNBALBRACK 10001
  39 #define EUNDEFVAR   10002
  40 #define EUNBALPER   10000
  41
  42 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
  43 #define MAX_INTERFACE_LENGTH 10
  44 #endif
  45
  46 #define debug_noise(fmt, args...)
  47
  48 /* Forward declaration */
  49 struct interface_defn_t;
  50
  51 typedef int (execfn)(char *command);
  52
  53 struct method_t
  54 {
  55         char *name;
  56         int (*up)(struct interface_defn_t *ifd, execfn *e);
  57         int (*down)(struct interface_defn_t *ifd, execfn *e);
  58 };
  59
  60 struct address_family_t
  61 {
  62         char *name;
  63         int n_methods;
  64         struct method_t *method;
  65 };
  66
  67 struct mapping_defn_t
  68 {
  69         struct mapping_defn_t *next;
  70
  71         int max_matches;
  72         int n_matches;
  73         char **match;
  74
  75         char *script;
  76
  77         int max_mappings;
  78         int n_mappings;
  79         char **mapping;
  80 };
  81
  82 struct variable_t
  83 {
  84         char *name;
  85         char *value;
  86 };
  87
  88 struct interface_defn_t
  89 {
  90         struct address_family_t *address_family;
  91         struct method_t *method;
  92
  93         char *iface;
  94         int max_options;
  95         int n_options;
  96         struct variable_t *option;
  97 };
  98
  99 struct interfaces_file_t
 100 {
 101         llist_t *autointerfaces;
 102         llist_t *ifaces;
 103         struct mapping_defn_t *mappings;
 104 };
 105
 106 static char no_act = 0;
 107 static char verbose = 0;
 108 static char **__myenviron = NULL;
 109
 110 #if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
 111
 112 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 113
 114 static unsigned int count_bits(unsigned int a)
 115 {
 116         unsigned int result;
 117         result = (a & 0x55) + ((a >> 1) & 0x55);
 118         result = (result & 0x33) + ((result >> 2) & 0x33);
 119         return((result & 0x0F) + ((result >> 4) & 0x0F));
 120 }
 121
 122 static int count_netmask_bits(char *dotted_quad)
 123 {
 124         unsigned int result, a, b, c, d;
 125         /* Found a netmask...  Check if it is dotted quad */
 126         if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
 127                 return -1;
 128         result = count_bits(a);
 129         result += count_bits(b);
 130         result += count_bits(c);
 131         result += count_bits(d);
 132         return ((int)result);
 133 }
 134 #endif
 135
 136 static void addstr(char **buf, size_t *len, size_t *pos, char *str, size_t str_length)
 137 {
 138         if (*pos + str_length >= *len) {
 139                 char *newbuf;
 140
 141                 newbuf = xrealloc(*buf, *len * 2 + str_length + 1);
 142                 *buf = newbuf;
 143                 *len = *len * 2 + str_length + 1;
 144         }
 145
 146         while (str_length-- >= 1) {
 147                 (*buf)[(*pos)++] = *str;
 148                 str++;
 149         }
 150         (*buf)[*pos] = '\0';
 151 }
 152
 153 static int strncmpz(char *l, char *r, size_t llen)
 154 {
 155         int i = strncmp(l, r, llen);
 156
 157         if (i == 0) {
 158                 return(-r[llen]);
 159         } else {
 160                 return(i);
 161         }
 162 }
 163
 164 static char *get_var(char *id, size_t idlen, struct interface_defn_t *ifd)
 165 {
 166         int i;
 167
 168         if (strncmpz(id, "iface", idlen) == 0) {
 169                 char *result;
 170                 static char label_buf[20];
 171                 strncpy(label_buf, ifd->iface, 19);
 172                 label_buf[19]=0;
 173                 result = strchr(label_buf, ':');
 174                 if (result) {
 175                         *result=0;
 176                 }
 177                 return( label_buf);
 178         } else if (strncmpz(id, "label", idlen) == 0) {
 179                 return (ifd->iface);
 180         } else {
 181                 for (i = 0; i < ifd->n_options; i++) {
 182                         if (strncmpz(id, ifd->option[i].name, idlen) == 0) {
 183                                 return (ifd->option[i].value);
 184                         }
 185                 }
 186         }
 187
 188         return(NULL);
 189 }
 190
 191 static char *parse(char *command, struct interface_defn_t *ifd)
 192 {
 193
 194         char *result = NULL;
 195         size_t pos = 0, len = 0;
 196         size_t old_pos[MAX_OPT_DEPTH] = { 0 };
 197         int okay[MAX_OPT_DEPTH] = { 1 };
 198         int opt_depth = 1;
 199
 200         while (*command) {
 201                 switch (*command) {
 202
 203                         default:
 204                                 addstr(&result, &len, &pos, command, 1);
 205                                 command++;
 206                                 break;
 207                         case '\\':
 208                                 if (command[1]) {
 209                                         addstr(&result, &len, &pos, command + 1, 1);
 210                                         command += 2;
 211                                 } else {
 212                                         addstr(&result, &len, &pos, command, 1);
 213                                         command++;
 214                                 }
 215                                 break;
 216                         case '[':
 217                                 if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
 218                                         old_pos[opt_depth] = pos;
 219                                         okay[opt_depth] = 1;
 220                                         opt_depth++;
 221                                         command += 2;
 222                                 } else {
 223                                         addstr(&result, &len, &pos, "[", 1);
 224                                         command++;
 225                                 }
 226                                 break;
 227                         case ']':
 228                                 if (command[1] == ']' && opt_depth > 1) {
 229                                         opt_depth--;
 230                                         if (!okay[opt_depth]) {
 231                                                 pos = old_pos[opt_depth];
 232                                                 result[pos] = '\0';
 233                                         }
 234                                         command += 2;
 235                                 } else {
 236                                         addstr(&result, &len, &pos, "]", 1);
 237                                         command++;
 238                                 }
 239                                 break;
 240                         case '%':
 241                                 {
 242                                         char *nextpercent;
 243                                         char *varvalue;
 244
 245                                         command++;
 246                                         nextpercent = strchr(command, '%');
 247                                         if (!nextpercent) {
 248                                                 errno = EUNBALPER;
 249                                                 free(result);
 250                                                 return (NULL);
 251                                         }
 252
 253                                         varvalue = get_var(command, nextpercent - command, ifd);
 254
 255                                         if (varvalue) {
 256                                                 addstr(&result, &len, &pos, varvalue, strlen(varvalue));
 257                                         } else {
 258 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 259                                                 /* Sigh...  Add a special case for 'ip' to convert from
 260                                                  * dotted quad to bit count style netmasks.  */
 261                                                 if (strncmp(command, "bnmask", 6)==0) {
 262                                                         int res;
 263                                                         varvalue = get_var("netmask", 7, ifd);
 264                                                         if (varvalue && (res=count_netmask_bits(varvalue)) > 0) {
 265                                                                 char argument[255];
 266                                                                 sprintf(argument, "%d", res);
 267                                                                 addstr(&result, &len, &pos, argument, strlen(argument));
 268                                                                 command = nextpercent + 1;
 269                                                                 break;
 270                                                         }
 271                                                 }
 272 #endif
 273                                                 okay[opt_depth - 1] = 0;
 274                                         }
 275
 276                                         command = nextpercent + 1;
 277                                 }
 278                                 break;
 279                 }
 280         }
 281
 282         if (opt_depth > 1) {
 283                 errno = EUNBALBRACK;
 284                 free(result);
 285                 return(NULL);
 286         }
 287
 288         if (!okay[0]) {
 289                 errno = EUNDEFVAR;
 290                 free(result);
 291                 return(NULL);
 292         }
 293
 294         return(result);
 295 }
 296
 297 static int execute(char *command, struct interface_defn_t *ifd, execfn *exec)
 298 {
 299         char *out;
 300         int ret;
 301
 302         out = parse(command, ifd);
 303         if (!out) {
 304                 return(0);
 305         }
 306         ret = (*exec) (out);
 307
 308         free(out);
 309         if (ret != 1) {
 310                 return(0);
 311         }
 312         return(1);
 313 }
 314 #endif
 315
 316 #ifdef CONFIG_FEATURE_IFUPDOWN_IPV6
 317 static int loopback_up6(struct interface_defn_t *ifd, execfn *exec)
 318 {
 319 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 320         int result;
 321         result =execute("ip addr add ::1 dev %iface%", ifd, exec);
 322         result += execute("ip link set %iface% up", ifd, exec);
 323         return ((result == 2) ? 2 : 0);
 324 #else
 325         return( execute("ifconfig %iface% add ::1", ifd, exec));
 326 #endif
 327 }
 328
 329 static int loopback_down6(struct interface_defn_t *ifd, execfn *exec)
 330 {
 331 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 332         return(execute("ip link set %iface% down", ifd, exec));
 333 #else
 334         return(execute("ifconfig %iface% del ::1", ifd, exec));
 335 #endif
 336 }
 337
 338 static int static_up6(struct interface_defn_t *ifd, execfn *exec)
 339 {
 340         int result;
 341 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 342         result = execute("ip addr add %address%/%netmask% dev %iface% [[label %label%]]", ifd, exec);
 343         result += execute("ip link set [[mtu %mtu%]] [[address %hwaddress%]] %iface% up", ifd, exec);
 344         result += execute("[[ ip route add ::/0 via %gateway% ]]", ifd, exec);
 345 #else
 346         result = execute("ifconfig %iface% [[media %media%]] [[hw %hwaddress%]] [[mtu %mtu%]] up", ifd, exec);
 347         result += execute("ifconfig %iface% add %address%/%netmask%", ifd, exec);
 348         result += execute("[[ route -A inet6 add ::/0 gw %gateway% ]]", ifd, exec);
 349 #endif
 350         return ((result == 3) ? 3 : 0);
 351 }
 352
 353 static int static_down6(struct interface_defn_t *ifd, execfn *exec)
 354 {
 355 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 356         return(execute("ip link set %iface% down", ifd, exec));
 357 #else
 358         return(execute("ifconfig %iface% down", ifd, exec));
 359 #endif
 360 }
 361
 362 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 363 static int v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
 364 {
 365         int result;
 366         result = execute("ip tunnel add %iface% mode sit remote "
 367                                 "%endpoint% [[local %local%]] [[ttl %ttl%]]", ifd, exec);
 368         result += execute("ip link set %iface% up", ifd, exec);
 369         result += execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec);
 370         result += execute("[[ ip route add ::/0 via %gateway% ]]", ifd, exec);
 371         return ((result == 4) ? 4 : 0);
 372 }
 373
 374 static int v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
 375 {
 376         return( execute("ip tunnel del %iface%", ifd, exec));
 377 }
 378 #endif
 379
 380 static struct method_t methods6[] = {
 381 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 382         { "v4tunnel", v4tunnel_up, v4tunnel_down, },
 383 #endif
 384         { "static", static_up6, static_down6, },
 385         { "loopback", loopback_up6, loopback_down6, },
 386 };
 387
 388 static struct address_family_t addr_inet6 = {
 389         "inet6",
 390         sizeof(methods6) / sizeof(struct method_t),
 391         methods6
 392 };
 393 #endif /* CONFIG_FEATURE_IFUPDOWN_IPV6 */
 394
 395 #ifdef CONFIG_FEATURE_IFUPDOWN_IPV4
 396 static int loopback_up(struct interface_defn_t *ifd, execfn *exec)
 397 {
 398 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 399         int result;
 400         result = execute("ip addr add 127.0.0.1/8 dev %iface%", ifd, exec);
 401         result += execute("ip link set %iface% up", ifd, exec);
 402         return ((result == 2) ? 2 : 0);
 403 #else
 404         return( execute("ifconfig %iface% 127.0.0.1 up", ifd, exec));
 405 #endif
 406 }
 407
 408 static int loopback_down(struct interface_defn_t *ifd, execfn *exec)
 409 {
 410 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 411         int result;
 412         result = execute("ip addr flush dev %iface%", ifd, exec);
 413         result += execute("ip link set %iface% down", ifd, exec);
 414         return ((result == 2) ? 2 : 0);
 415 #else
 416         return( execute("ifconfig %iface% 127.0.0.1 down", ifd, exec));
 417 #endif
 418 }
 419
 420 static int static_up(struct interface_defn_t *ifd, execfn *exec)
 421 {
 422         int result;
 423 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 424         result = execute("ip addr add %address%/%bnmask% [[broadcast %broadcast%]] "
 425                         "dev %iface% [[peer %pointopoint%]] [[label %label%]]", ifd, exec);
 426         result += execute("ip link set [[mtu %mtu%]] [[address %hwaddress%]] %iface% up", ifd, exec);
 427         result += execute("[[ ip route add default via %gateway% dev %iface% ]]", ifd, exec);
 428         return ((result == 3) ? 3 : 0);
 429 #else
 430         result = execute("ifconfig %iface% %address% netmask %netmask% "
 431                                 "[[broadcast %broadcast%]] [[pointopoint %pointopoint%]] "
 432                                 "[[media %media%]] [[mtu %mtu%]] [[hw %hwaddress%]] up",
 433                                 ifd, exec);
 434         result += execute("[[ route add default gw %gateway% %iface% ]]", ifd, exec);
 435         return ((result == 2) ? 2 : 0);
 436 #endif
 437 }
 438
 439 static int static_down(struct interface_defn_t *ifd, execfn *exec)
 440 {
 441         int result;
 442 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
 443         result = execute("ip addr flush dev %iface%", ifd, exec);
 444         result += execute("ip link set %iface% down", ifd, exec);
 445 #else
 446         result = execute("[[ route del default gw %gateway% %iface% ]]", ifd, exec);
 447         result += execute("ifconfig %iface% down", ifd, exec);
 448 #endif
 449         return ((result == 2) ? 2 : 0);
 450 }
 451
 452 static int execable(char *program)
 453 {
 454         struct stat buf;
 455         if (0 == stat(program, &buf)) {
 456                 if (S_ISREG(buf.st_mode) && (S_IXUSR & buf.st_mode)) {
 457                         return(1);
 458                 }
 459         }
 460         return(0);
 461 }
 462
 463 static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 464 {
 465         if (execable("/sbin/udhcpc")) {
 466                 return( execute("udhcpc -n -p /var/run/udhcpc.%iface%.pid -i "
 467                                         "%iface% [[-H %hostname%]] [[-c %clientid%]]", ifd, exec));
 468         } else if (execable("/sbin/pump")) {
 469                 return( execute("pump -i %iface% [[-h %hostname%]] [[-l %leasehours%]]", ifd, exec));
 470         } else if (execable("/sbin/dhclient")) {
 471                 return( execute("dhclient -pf /var/run/dhclient.%iface%.pid %iface%", ifd, exec));
 472         } else if (execable("/sbin/dhcpcd")) {
 473                 return( execute("dhcpcd [[-h %hostname%]] [[-i %vendor%]] [[-I %clientid%]] "
 474                                         "[[-l %leasetime%]] %iface%", ifd, exec));
 475         }
 476         return(0);
 477 }
 478
 479 static int dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 480 {
 481         int result = 0;
 482         if (execable("/sbin/udhcpc")) {
 483                 /* SIGUSR2 forces udhcpc to release the current lease and go inactive,
 484                  * and SIGTERM causes udhcpc to exit.  Signals are queued and processed
 485                  * sequentially so we don't need to sleep */
 486                 result = execute("kill -USR2 `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec);
 487                 result += execute("kill -TERM `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec);
 488         } else if (execable("/sbin/pump")) {
 489                 result = execute("pump -i %iface% -k", ifd, exec);
 490         } else if (execable("/sbin/dhclient")) {
 491                 result = execute("kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null", ifd, exec);
 492         } else if (execable("/sbin/dhcpcd")) {
 493                 result = execute("dhcpcd -k %iface%", ifd, exec);
 494         }
 495         return (result || static_down(ifd, exec));
 496 }
 497
 498 static int bootp_up(struct interface_defn_t *ifd, execfn *exec)
 499 {
 500         return( execute("bootpc [[--bootfile %bootfile%]] --dev %iface% "
 501                                 "[[--server %server%]] [[--hwaddr %hwaddr%]] "
 502                                 "--returniffail --serverbcast", ifd, exec));
 503 }
 504
 505 static int ppp_up(struct interface_defn_t *ifd, execfn *exec)
 506 {
 507         return( execute("pon [[%provider%]]", ifd, exec));
 508 }
 509
 510 static int ppp_down(struct interface_defn_t *ifd, execfn *exec)
 511 {
 512         return( execute("poff [[%provider%]]", ifd, exec));
 513 }
 514
 515 static int wvdial_up(struct interface_defn_t *ifd, execfn *exec)
 516 {
 517         return( execute("/sbin/start-stop-daemon --start -x /usr/bin/wvdial "
 518                                 "-p /var/run/wvdial.%iface% -b -m -- [[ %provider% ]]", ifd, exec));
 519 }
 520
 521 static int wvdial_down(struct interface_defn_t *ifd, execfn *exec)
 522 {
 523         return( execute("/sbin/start-stop-daemon --stop -x /usr/bin/wvdial "
 524                                 "-p /var/run/wvdial.%iface% -s 2", ifd, exec));
 525 }
 526
 527 static struct method_t methods[] =
 528 {
 529         { "wvdial", wvdial_up, wvdial_down, },
 530         { "ppp", ppp_up, ppp_down, },
 531         { "static", static_up, static_down, },
 532         { "bootp", bootp_up, static_down, },
 533         { "dhcp", dhcp_up, dhcp_down, },
 534         { "loopback", loopback_up, loopback_down, },
 535 };
 536
 537 static struct address_family_t addr_inet =
 538 {
 539         "inet",
 540         sizeof(methods) / sizeof(struct method_t),
 541         methods
 542 };
 543
 544 #endif  /* ifdef CONFIG_FEATURE_IFUPDOWN_IPV4 */
 545
 546 static char *next_word(char **buf)
 547 {
 548         unsigned short length;
 549         char *word;
 550
 551         if ((buf == NULL) || (*buf == NULL) || (**buf == '\0')) {
 552                 return NULL;
 553         }
 554
 555         /* Skip over leading whitespace */
 556         word = *buf;
 557         while (isspace(*word)) {
 558                 ++word;
 559         }
 560
 561         /* Skip over comments */
 562         if (*word == '#') {
 563                 return(NULL);
 564         }
 565
 566         /* Find the length of this word */
 567         length = strcspn(word, " \t\n");
 568         if (length == 0) {
 569                 return(NULL);
 570         }
 571         *buf = word + length;
 572         /*DBU:[dave@cray.com] if we are already at EOL dont't increment beyond it */
 573         if (**buf) {
 574                 **buf = '\0';
 575                 (*buf)++;
 576         }
 577
 578         return word;
 579 }
 580
 581 static struct address_family_t *get_address_family(struct address_family_t *af[], char *name)
 582 {
 583         int i;
 584
 585         for (i = 0; af[i]; i++) {
 586                 if (strcmp(af[i]->name, name) == 0) {
 587                         return af[i];
 588                 }
 589         }
 590         return NULL;
 591 }
 592
 593 static struct method_t *get_method(struct address_family_t *af, char *name)
 594 {
 595         int i;
 596
 597         for (i = 0; i < af->n_methods; i++) {
 598                 if (strcmp(af->method[i].name, name) == 0) {
 599                         return &af->method[i];
 600                 }
 601         }
 602         return(NULL);
 603 }
 604
 605 static const llist_t *find_list_string(const llist_t *list, const char *string)
 606 {
 607         while (list) {
 608                 if (strcmp(list->data, string) == 0) {
 609                         return(list);
 610                 }
 611                 list = list->link;
 612         }
 613         return(NULL);
 614 }
 615
 616 static struct interfaces_file_t *read_interfaces(const char *filename)
 617 {
 618 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
 619         struct mapping_defn_t *currmap = NULL;
 620 #endif
 621         struct interface_defn_t *currif = NULL;
 622         struct interfaces_file_t *defn;
 623         FILE *f;
 624         char *firstword;
 625         char *buf;
 626
 627         enum { NONE, IFACE, MAPPING } currently_processing = NONE;
 628
 629         defn = xzalloc(sizeof(struct interfaces_file_t));
 630
 631         f = bb_xfopen(filename, "r");
 632
 633         while ((buf = bb_get_chomped_line_from_file(f)) != NULL) {
 634                 char *buf_ptr = buf;
 635
 636                 firstword = next_word(&buf_ptr);
 637                 if (firstword == NULL) {
 638                         free(buf);
 639                         continue;       /* blank line */
 640                 }
 641
 642                 if (strcmp(firstword, "mapping") == 0) {
 643 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
 644                         currmap = xzalloc(sizeof(struct mapping_defn_t));
 645
 646                         while ((firstword = next_word(&buf_ptr)) != NULL) {
 647                                 if (currmap->max_matches == currmap->n_matches) {
 648                                         currmap->max_matches = currmap->max_matches * 2 + 1;
 649                                         currmap->match = xrealloc(currmap->match, sizeof(currmap->match) * currmap->max_matches);
 650                                 }
 651
 652                                 currmap->match[currmap->n_matches++] = bb_xstrdup(firstword);
 653                         }
 654                         currmap->max_mappings = 0;
 655                         currmap->n_mappings = 0;
 656                         currmap->mapping = NULL;
 657                         currmap->script = NULL;
 658                         {
 659                                 struct mapping_defn_t **where = &defn->mappings;
 660                                 while (*where != NULL) {
 661                                         where = &(*where)->next;
 662                                 }
 663                                 *where = currmap;
 664                                 currmap->next = NULL;
 665                         }
 666                         debug_noise("Added mapping\n");
 667 #endif
 668                         currently_processing = MAPPING;
 669                 } else if (strcmp(firstword, "iface") == 0) {
 670                         {
 671                                 char *iface_name;
 672                                 char *address_family_name;
 673                                 char *method_name;
 674                                 struct address_family_t *addr_fams[] = {
 675 #ifdef CONFIG_FEATURE_IFUPDOWN_IPV4
 676                                         &addr_inet,
 677 #endif
 678 #ifdef CONFIG_FEATURE_IFUPDOWN_IPV6
 679                                         &addr_inet6,
 680 #endif
 681                                         NULL
 682                                 };
 683
 684                                 currif = xzalloc(sizeof(struct interface_defn_t));
 685                                 iface_name = next_word(&buf_ptr);
 686                                 address_family_name = next_word(&buf_ptr);
 687                                 method_name = next_word(&buf_ptr);
 688
 689                                 if (buf_ptr == NULL) {
 690                                         bb_error_msg("too few parameters for line \"%s\"", buf);
 691                                         return NULL;
 692                                 }
 693
 694                                 /* ship any trailing whitespace */
 695                                 while (isspace(*buf_ptr)) {
 696                                         ++buf_ptr;
 697                                 }
 698
 699                                 if (buf_ptr[0] != '\0') {
 700                                         bb_error_msg("too many parameters \"%s\"", buf);
 701                                         return NULL;
 702                                 }
 703
 704                                 currif->iface = bb_xstrdup(iface_name);
 705
 706                                 currif->address_family = get_address_family(addr_fams, address_family_name);
 707                                 if (!currif->address_family) {
 708                                         bb_error_msg("unknown address type \"%s\"", address_family_name);
 709                                         return NULL;
 710                                 }
 711
 712                                 currif->method = get_method(currif->address_family, method_name);
 713                                 if (!currif->method) {
 714                                         bb_error_msg("unknown method \"%s\"", method_name);
 715                                         return NULL;
 716                                 }
 717
 718
 719                                 {
 720                                         llist_t *iface_list;
 721                                         for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
 722                                                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
 723                                                 if ((strcmp(tmp->iface, currif->iface) == 0) &&
 724                                                         (tmp->address_family == currif->address_family)) {
 725                                                         bb_error_msg("duplicate interface \"%s\"", tmp->iface);
 726                                                         return NULL;
 727                                                 }
 728                                         }
 729
 730                                         llist_add_to_end(&(defn->ifaces), (char*)currif);
 731                                 }
 732                                 debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
 733                         }
 734                         currently_processing = IFACE;
 735                 } else if (strcmp(firstword, "auto") == 0) {
 736                         while ((firstword = next_word(&buf_ptr)) != NULL) {
 737
 738                                 /* Check the interface isnt already listed */
 739                                 if (find_list_string(defn->autointerfaces, firstword)) {
 740                                         bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
 741                                 }
 742
 743                                 /* Add the interface to the list */
 744                                 llist_add_to_end(&(defn->autointerfaces), bb_xstrdup(firstword));
 745                                 debug_noise("\nauto %s\n", firstword);
 746                         }
 747                         currently_processing = NONE;
 748                 } else {
 749                         switch (currently_processing) {
 750                                 case IFACE:
 751                                         {
 752                                                 int i;
 753
 754                                                 if (strlen(buf_ptr) == 0) {
 755                                                         bb_error_msg("option with empty value \"%s\"", buf);
 756                                                         return NULL;
 757                                                 }
 758
 759                                                 if (strcmp(firstword, "up") != 0
 760                                                                 && strcmp(firstword, "down") != 0
 761                                                                 && strcmp(firstword, "pre-up") != 0
 762                                                                 && strcmp(firstword, "post-down") != 0) {
 763                                                         for (i = 0; i < currif->n_options; i++) {
 764                                                                 if (strcmp(currif->option[i].name, firstword) == 0) {
 765                                                                         bb_error_msg("duplicate option \"%s\"", buf);
 766                                                                         return NULL;
 767                                                                 }
 768                                                         }
 769                                                 }
 770                                         }
 771                                         if (currif->n_options >= currif->max_options) {
 772                                                 struct variable_t *opt;
 773
 774                                                 currif->max_options = currif->max_options + 10;
 775                                                 opt = xrealloc(currif->option, sizeof(*opt) * currif->max_options);
 776                                                 currif->option = opt;
 777                                         }
 778                                         currif->option[currif->n_options].name = bb_xstrdup(firstword);
 779                                         currif->option[currif->n_options].value = bb_xstrdup(buf_ptr);
 780                                         if (!currif->option[currif->n_options].name) {
 781                                                 perror(filename);
 782                                                 return NULL;
 783                                         }
 784                                         if (!currif->option[currif->n_options].value) {
 785                                                 perror(filename);
 786                                                 return NULL;
 787                                         }
 788                                         debug_noise("\t%s=%s\n", currif->option[currif->n_options].name,
 789                                                         currif->option[currif->n_options].value);
 790                                         currif->n_options++;
 791                                         break;
 792                                 case MAPPING:
 793 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
 794                                         if (strcmp(firstword, "script") == 0) {
 795                                                 if (currmap->script != NULL) {
 796                                                         bb_error_msg("duplicate script in mapping \"%s\"", buf);
 797                                                         return NULL;
 798                                                 } else {
 799                                                         currmap->script = bb_xstrdup(next_word(&buf_ptr));
 800                                                 }
 801                                         } else if (strcmp(firstword, "map") == 0) {
 802                                                 if (currmap->max_mappings == currmap->n_mappings) {
 803                                                         currmap->max_mappings = currmap->max_mappings * 2 + 1;
 804                                                         currmap->mapping = xrealloc(currmap->mapping, sizeof(char *) * currmap->max_mappings);
 805                                                 }
 806                                                 currmap->mapping[currmap->n_mappings] = bb_xstrdup(next_word(&buf_ptr));
 807                                                 currmap->n_mappings++;
 808                                         } else {
 809                                                 bb_error_msg("misplaced option \"%s\"", buf);
 810                                                 return NULL;
 811                                         }
 812 #endif
 813                                         break;
 814                                 case NONE:
 815                                 default:
 816                                         bb_error_msg("misplaced option \"%s\"", buf);
 817                                         return NULL;
 818                         }
 819                 }
 820                 free(buf);
 821         }
 822         if (ferror(f) != 0) {
 823                 bb_perror_msg_and_die("%s", filename);
 824         }
 825         fclose(f);
 826
 827         return defn;
 828 }
 829
 830 static char *setlocalenv(char *format, const char *name, const char *value)
 831 {
 832         char *result;
 833         char *here;
 834         char *there;
 835
 836         result = bb_xasprintf(format, name, value);
 837
 838         for (here = there = result; *there != '=' && *there; there++) {
 839                 if (*there == '-')
 840                         *there = '_';
 841                 if (isalpha(*there))
 842                         *there = toupper(*there);
 843
 844                 if (isalnum(*there) || *there == '_') {
 845                         *here = *there;
 846                         here++;
 847                 }
 848         }
 849         memmove(here, there, strlen(there) + 1);
 850
 851         return result;
 852 }
 853
 854 static void set_environ(struct interface_defn_t *iface, const char *mode)
 855 {
 856         char **environend;
 857         int i;
 858         const int n_env_entries = iface->n_options + 5;
 859         char **ppch;
 860
 861         if (__myenviron != NULL) {
 862                 for (ppch = __myenviron; *ppch; ppch++) {
 863                         free(*ppch);
 864                         *ppch = NULL;
 865                 }
 866                 free(__myenviron);
 867         }
 868         __myenviron = xzalloc(sizeof(char *) * (n_env_entries + 1 /* for final NULL */ ));
 869         environend = __myenviron;
 870
 871         for (i = 0; i < iface->n_options; i++) {
 872                 if (strcmp(iface->option[i].name, "up") == 0
 873                                 || strcmp(iface->option[i].name, "down") == 0
 874                                 || strcmp(iface->option[i].name, "pre-up") == 0
 875                                 || strcmp(iface->option[i].name, "post-down") == 0) {
 876                         continue;
 877                 }
 878                 *(environend++) = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
 879         }
 880
 881         *(environend++) = setlocalenv("%s=%s", "IFACE", iface->iface);
 882         *(environend++) = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
 883         *(environend++) = setlocalenv("%s=%s", "METHOD", iface->method->name);
 884         *(environend++) = setlocalenv("%s=%s", "MODE", mode);
 885         *(environend++) = setlocalenv("%s=%s", "PATH", "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin");
 886 }
 887
 888 static int doit(char *str)
 889 {
 890         if (verbose || no_act) {
 891                 printf("%s\n", str);
 892         }
 893         if (!no_act) {
 894                 pid_t child;
 895                 int status;
 896
 897                 fflush(NULL);
 898                 switch (child = fork()) {
 899                         case -1:                /* failure */
 900                                 return 0;
 901                         case 0:         /* child */
 902                                 execle(DEFAULT_SHELL, DEFAULT_SHELL, "-c", str, NULL, __myenviron);
 903                                 exit(127);
 904                 }
 905                 waitpid(child, &status, 0);
 906                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 907                         return 0;
 908                 }
 909         }
 910         return (1);
 911 }
 912
 913 static int execute_all(struct interface_defn_t *ifd, const char *opt)
 914 {
 915         int i;
 916         char *buf;
 917         for (i = 0; i < ifd->n_options; i++) {
 918                 if (strcmp(ifd->option[i].name, opt) == 0) {
 919                         if (!doit(ifd->option[i].value)) {
 920                                 return 0;
 921                         }
 922                 }
 923         }
 924
 925         buf = bb_xasprintf("run-parts /etc/network/if-%s.d", opt);
 926         if (doit(buf) != 1) {
 927                 return 0;
 928         }
 929         return 1;
 930 }
 931
 932 static int check(char *str) {
 933         return str != NULL;
 934 }
 935
 936 static int iface_up(struct interface_defn_t *iface)
 937 {
 938         if (!iface->method->up(iface,check)) return -1;
 939         set_environ(iface, "start");
 940         if (!execute_all(iface, "pre-up")) return 0;
 941         if (!iface->method->up(iface, doit)) return 0;
 942         if (!execute_all(iface, "up")) return 0;
 943         return 1;
 944 }
 945
 946 static int iface_down(struct interface_defn_t *iface)
 947 {
 948         if (!iface->method->down(iface,check)) return -1;
 949         set_environ(iface, "stop");
 950         if (!execute_all(iface, "down")) return 0;
 951         if (!iface->method->down(iface, doit)) return 0;
 952         if (!execute_all(iface, "post-down")) return 0;
 953         return 1;
 954 }
 955
 956 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
 957 static int popen2(FILE **in, FILE **out, char *command, ...)
 958 {
 959         va_list ap;
 960         char *argv[11] = { command };
 961         int argc;
 962         int infd[2], outfd[2];
 963         pid_t pid;
 964
 965         argc = 1;
 966         va_start(ap, command);
 967         while ((argc < 10) && (argv[argc] = va_arg(ap, char *))) {
 968                 argc++;
 969         }
 970         argv[argc] = NULL;      /* make sure */
 971         va_end(ap);
 972
 973         if (pipe(infd) != 0) {
 974                 return 0;
 975         }
 976
 977         if (pipe(outfd) != 0) {
 978                 close(infd[0]);
 979                 close(infd[1]);
 980                 return 0;
 981         }
 982
 983         fflush(NULL);
 984         switch (pid = fork()) {
 985                 case -1:                        /* failure */
 986                         close(infd[0]);
 987                         close(infd[1]);
 988                         close(outfd[0]);
 989                         close(outfd[1]);
 990                         return 0;
 991                 case 0:                 /* child */
 992                         dup2(infd[0], 0);
 993                         dup2(outfd[1], 1);
 994                         close(infd[0]);
 995                         close(infd[1]);
 996                         close(outfd[0]);
 997                         close(outfd[1]);
 998                         execvp(command, argv);
 999                         exit(127);
1000                 default:                        /* parent */
1001                         *in = fdopen(infd[1], "w");
1002                         *out = fdopen(outfd[0], "r");
1003                         close(infd[0]);
1004                         close(outfd[1]);
1005                         return pid;
1006         }
1007         /* unreached */
1008 }
1009
1010 static char *run_mapping(char *physical, struct mapping_defn_t * map)
1011 {
1012         FILE *in, *out;
1013         int i, status;
1014         pid_t pid;
1015
1016         char *logical = bb_xstrdup(physical);
1017
1018         /* Run the mapping script. */
1019         pid = popen2(&in, &out, map->script, physical, NULL);
1020
1021         /* popen2() returns 0 on failure. */
1022         if (pid == 0)
1023                 return logical;
1024
1025         /* Write mappings to stdin of mapping script. */
1026         for (i = 0; i < map->n_mappings; i++) {
1027                 fprintf(in, "%s\n", map->mapping[i]);
1028         }
1029         fclose(in);
1030         waitpid(pid, &status, 0);
1031
1032         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
1033                 /* If the mapping script exited successfully, try to
1034                  * grab a line of output and use that as the name of the
1035                  * logical interface. */
1036                 char *new_logical = (char *)xmalloc(MAX_INTERFACE_LENGTH);
1037
1038                 if (fgets(new_logical, MAX_INTERFACE_LENGTH, out)) {
1039                         /* If we are able to read a line of output from the script,
1040                          * remove any trailing whitespace and use this value
1041                          * as the name of the logical interface. */
1042                         char *pch = new_logical + strlen(new_logical) - 1;
1043
1044                         while (pch >= new_logical && isspace(*pch))
1045                                 *(pch--) = '\0';
1046
1047                         free(logical);
1048                         logical = new_logical;
1049                 } else {
1050                         /* If we are UNABLE to read a line of output, discard our
1051                          * freshly allocated memory. */
1052                         free(new_logical);
1053                 }
1054         }
1055
1056         fclose(out);
1057
1058         return logical;
1059 }
1060 #endif /* CONFIG_FEATURE_IFUPDOWN_MAPPING */
1061
1062 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
1063 {
1064         unsigned short iface_len = strlen(iface);
1065         llist_t *search = state_list;
1066
1067         while (search) {
1068                 if ((strncmp(search->data, iface, iface_len) == 0) &&
1069                                 (search->data[iface_len] == '=')) {
1070                         return(search);
1071                 }
1072                 search = search->link;
1073         }
1074         return(NULL);
1075 }
1076
1077 int ifupdown_main(int argc, char **argv)
1078 {
1079         int (*cmds) (struct interface_defn_t *) = NULL;
1080         struct interfaces_file_t *defn;
1081         llist_t *state_list = NULL;
1082         llist_t *target_list = NULL;
1083         const char *interfaces = "/etc/network/interfaces";
1084         const char *statefile = "/var/run/ifstate";
1085
1086 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1087         int run_mappings = 1;
1088 #endif
1089         int do_all = 0;
1090         int force = 0;
1091         int any_failures = 0;
1092         int i;
1093
1094         if (bb_applet_name[2] == 'u') {
1095                 /* ifup command */
1096                 cmds = iface_up;
1097         } else {
1098                 /* ifdown command */
1099                 cmds = iface_down;
1100         }
1101
1102 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1103         while ((i = getopt(argc, argv, "i:hvnamf")) != -1)
1104 #else
1105                 while ((i = getopt(argc, argv, "i:hvnaf")) != -1)
1106 #endif
1107                 {
1108                         switch (i) {
1109                                 case 'i':       /* interfaces */
1110                                         interfaces = optarg;
1111                                         break;
1112                                 case 'v':       /* verbose */
1113                                         verbose = 1;
1114                                         break;
1115                                 case 'a':       /* all */
1116                                         do_all = 1;
1117                                         break;
1118                                 case 'n':       /* no-act */
1119                                         no_act = 1;
1120                                         break;
1121 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1122                                 case 'm':       /* no-mappings */
1123                                         run_mappings = 0;
1124                                         break;
1125 #endif
1126                                 case 'f':       /* force */
1127                                         force = 1;
1128                                         break;
1129                                 default:
1130                                         bb_show_usage();
1131                                         break;
1132                         }
1133                 }
1134
1135         if (argc - optind > 0) {
1136                 if (do_all) {
1137                         bb_show_usage();
1138                 }
1139         } else {
1140                 if (!do_all) {
1141                         bb_show_usage();
1142                 }
1143         }
1144
1145         debug_noise("reading %s file:\n", interfaces);
1146         defn = read_interfaces(interfaces);
1147         debug_noise("\ndone reading %s\n\n", interfaces);
1148
1149         if (!defn) {
1150                 exit(EXIT_FAILURE);
1151         }
1152
1153         /* Create a list of interfaces to work on */
1154         if (do_all) {
1155                 if (cmds == iface_up) {
1156                         target_list = defn->autointerfaces;
1157                 } else {
1158                         /* iface_down */
1159                         const llist_t *list = state_list;
1160                         while (list) {
1161                                 llist_add_to_end(&target_list, bb_xstrdup(list->data));
1162                                 list = list->link;
1163                         }
1164                         target_list = defn->autointerfaces;
1165                 }
1166         } else {
1167                 llist_add_to_end(&target_list, argv[optind]);
1168         }
1169
1170
1171         /* Update the interfaces */
1172         while (target_list) {
1173                 llist_t *iface_list;
1174                 struct interface_defn_t *currif;
1175                 char *iface;
1176                 char *liface;
1177                 char *pch;
1178                 int okay = 0;
1179                 int cmds_ret;
1180
1181                 iface = bb_xstrdup(target_list->data);
1182                 target_list = target_list->link;
1183
1184                 pch = strchr(iface, '=');
1185                 if (pch) {
1186                         *pch = '\0';
1187                         liface = bb_xstrdup(pch + 1);
1188                 } else {
1189                         liface = bb_xstrdup(iface);
1190                 }
1191
1192                 if (!force) {
1193                         const llist_t *iface_state = find_iface_state(state_list, iface);
1194
1195                         if (cmds == iface_up) {
1196                                 /* ifup */
1197                                 if (iface_state) {
1198                                         bb_error_msg("interface %s already configured", iface);
1199                                         continue;
1200                                 }
1201                         } else {
1202                                 /* ifdown */
1203                                 if (iface_state) {
1204                                         bb_error_msg("interface %s not configured", iface);
1205                                         continue;
1206                                 }
1207                         }
1208                 }
1209
1210 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1211                 if ((cmds == iface_up) && run_mappings) {
1212                         struct mapping_defn_t *currmap;
1213
1214                         for (currmap = defn->mappings; currmap; currmap = currmap->next) {
1215
1216                                 for (i = 0; i < currmap->n_matches; i++) {
1217                                         if (fnmatch(currmap->match[i], liface, 0) != 0)
1218                                                 continue;
1219                                         if (verbose) {
1220                                                 printf("Running mapping script %s on %s\n", currmap->script, liface);
1221                                         }
1222                                         liface = run_mapping(iface, currmap);
1223                                         break;
1224                                 }
1225                         }
1226                 }
1227 #endif
1228
1229
1230                 iface_list = defn->ifaces;
1231                 while (iface_list) {
1232                         currif = (struct interface_defn_t *) iface_list->data;
1233                         if (strcmp(liface, currif->iface) == 0) {
1234                                 char *oldiface = currif->iface;
1235
1236                                 okay = 1;
1237                                 currif->iface = iface;
1238
1239                                 debug_noise("\nConfiguring interface %s (%s)\n", liface, currif->address_family->name);
1240
1241                                 /* Call the cmds function pointer, does either iface_up() or iface_down() */
1242                                 cmds_ret = cmds(currif);
1243                                 if (cmds_ret == -1) {
1244                                         bb_error_msg("Don't seem to have all the variables for %s/%s.",
1245                                                         liface, currif->address_family->name);
1246                                         any_failures += 1;
1247                                 } else if (cmds_ret == 0) {
1248                                         any_failures += 1;
1249                                 }
1250
1251                                 currif->iface = oldiface;
1252                         }
1253                         iface_list = iface_list->link;
1254                 }
1255                 if (verbose) {
1256                         printf("\n");
1257                 }
1258
1259                 if (!okay && !force) {
1260                         bb_error_msg("Ignoring unknown interface %s", liface);
1261                         any_failures += 1;
1262                 } else {
1263                         llist_t *iface_state = find_iface_state(state_list, iface);
1264
1265                         if (cmds == iface_up) {
1266                                 char *newiface = bb_xasprintf("%s=%s", iface, liface);
1267                                 if (iface_state == NULL) {
1268                                         llist_add_to_end(&state_list, newiface);
1269                                 } else {
1270                                         free(iface_state->data);
1271                                         iface_state->data = newiface;
1272                                 }
1273                         } else {
1274                                 /* Remove an interface from the linked list */
1275                                 free(llist_pop(&iface_state));
1276                         }
1277                 }
1278         }
1279
1280         /* Actually write the new state */
1281         if (!no_act) {
1282                 FILE *state_fp = NULL;
1283
1284                 state_fp = bb_xfopen(statefile, "w");
1285                 while (state_list) {
1286                         if (state_list->data) {
1287                                 fputs(state_list->data, state_fp);
1288                                 fputc('\n', state_fp);
1289                         }
1290                         state_list = state_list->link;
1291                 }
1292                 fclose(state_fp);
1293         }
1294
1295         if (any_failures)
1296                 return 1;
1297         return 0;
1298 }