networking/ifupdown.c

   1 /*
   2  *  ifupdown for busybox
   3  *  Based on ifupdown by Anthony Towns
   4  *  Copyright (c) 1999 Anthony Towns <aj@azure.humbug.org.au>
   5  *
   6  *  Changes to upstream version
   7  *  Remove checks for kernel version, assume kernel version 2.2.0 or better
   8  *  Lines in the interfaces file cannot wrap.
   9  *  The default state file is moved to /var/run/ifstate
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 2 of the License, or
  14  *  (at your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful,
  17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *  GNU General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License
  22  *  along with this program; if not, write to the Free Software
  23  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24  */
  25
  26 #include <sys/stat.h>
  27 #include <sys/utsname.h>
  28 #include <sys/wait.h>
  29
  30 #include <ctype.h>
  31 #include <errno.h>
  32 #include <fcntl.h>
  33 #include <fnmatch.h>
  34 #include <getopt.h>
  35 #include <stdarg.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <unistd.h>
  40
  41 #include "libbb.h"
  42 //#include "busybox.h"
  43 //#include "config.h"
  44
  45 #define IFUPDOWN_VERSION "0.6.4"
  46
  47 typedef struct interface_defn_s interface_defn_t;
  48
  49 typedef int (execfn)(char *command);
  50 typedef int (command_set)(interface_defn_t *ifd, execfn *e);
  51
  52 typedef struct method_s {
  53         char *name;
  54         command_set *up;
  55         command_set *down;
  56 } method_t;
  57
  58 typedef struct address_family_s {
  59         char *name;
  60         int n_methods;
  61         method_t *method;
  62 } address_family_t;
  63
  64 typedef struct mapping_defn_s {
  65         struct mapping_defn_s *next;
  66
  67         int max_matches;
  68         int n_matches;
  69         char **match;
  70
  71         char *script;
  72
  73         int max_mappings;
  74         int n_mappings;
  75         char **mapping;
  76 } mapping_defn_t;
  77
  78 typedef struct variable_s {
  79         char *name;
  80         char *value;
  81 } variable_t;
  82
  83 struct interface_defn_s {
  84         struct interface_defn_s *next;
  85
  86         char *iface;
  87         address_family_t *address_family;
  88         method_t *method;
  89
  90         int automatic;
  91
  92         int max_options;
  93         int n_options;
  94         variable_t *option;
  95 };
  96
  97 typedef struct interfaces_file_s {
  98         int max_autointerfaces;
  99         int n_autointerfaces;
 100         char **autointerfaces;
 101
 102         interface_defn_t *ifaces;
 103         mapping_defn_t *mappings;
 104 } interfaces_file_t;
 105
 106 #define MAX_OPT_DEPTH 10
 107 #define EUNBALBRACK 10001
 108 #define EUNDEFVAR   10002
 109 #define MAX_VARNAME    32
 110 #define EUNBALPER   10000
 111
 112 static int no_act = 0;
 113 static int verbose = 0;
 114 static char **environ = NULL;
 115
 116 static void addstr(char **buf, size_t *len, size_t *pos, char *str, size_t str_length)
 117 {
 118         if (*pos + str_length >= *len) {
 119                 char *newbuf;
 120
 121                 newbuf = xrealloc(*buf, *len * 2 + str_length + 1);
 122                 *buf = newbuf;
 123                 *len = *len * 2 + str_length + 1;
 124         }
 125
 126         while (str_length-- >= 1) {
 127                 (*buf)[(*pos)++] = *str;
 128                 str++;
 129         }
 130         (*buf)[*pos] = '\0';
 131 }
 132
 133 static int strncmpz(char *l, char *r, size_t llen)
 134 {
 135         int i = strncmp(l, r, llen);
 136
 137         if (i == 0) {
 138                 return(-r[llen]);
 139         } else {
 140                 return(i);
 141         }
 142 }
 143
 144 static char *get_var(char *id, size_t idlen, interface_defn_t *ifd)
 145 {
 146         int i;
 147
 148         if (strncmpz(id, "iface", idlen) == 0) {
 149                 return (ifd->iface);
 150         } else {
 151                 for (i = 0; i < ifd->n_options; i++) {
 152                         if (strncmpz(id, ifd->option[i].name, idlen) == 0) {
 153                                 return (ifd->option[i].value);
 154                         }
 155                 }
 156         }
 157
 158         return(NULL);
 159 }
 160
 161 static char *parse(char *command, interface_defn_t *ifd)
 162 {
 163
 164         char *result = NULL;
 165         size_t pos = 0, len = 0;
 166         size_t old_pos[MAX_OPT_DEPTH] = { 0 };
 167         int okay[MAX_OPT_DEPTH] = { 1 };
 168         int opt_depth = 1;
 169
 170         while (*command) {
 171                 switch (*command) {
 172
 173                 default:
 174                         addstr(&result, &len, &pos, command, 1);
 175                         command++;
 176                         break;
 177                 case '\\':
 178                         if (command[1]) {
 179                                 addstr(&result, &len, &pos, command + 1, 1);
 180                                 command += 2;
 181                         } else {
 182                                 addstr(&result, &len, &pos, command, 1);
 183                                 command++;
 184                         }
 185                         break;
 186                 case '[':
 187                         if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
 188                                 old_pos[opt_depth] = pos;
 189                                 okay[opt_depth] = 1;
 190                                 opt_depth++;
 191                                 command += 2;
 192                         } else {
 193                                 addstr(&result, &len, &pos, "[", 1);
 194                                 command++;
 195                         }
 196                         break;
 197                 case ']':
 198                         if (command[1] == ']' && opt_depth > 1) {
 199                                 opt_depth--;
 200                                 if (!okay[opt_depth]) {
 201                                         pos = old_pos[opt_depth];
 202                                         result[pos] = '\0';
 203                                 }
 204                                 command += 2;
 205                         } else {
 206                                 addstr(&result, &len, &pos, "]", 1);
 207                                 command++;
 208                         }
 209                         break;
 210                 case '%':
 211                 {
 212                         char *nextpercent;
 213                         char *varvalue;
 214
 215                         command++;
 216                         nextpercent = strchr(command, '%');
 217                         if (!nextpercent) {
 218                                 errno = EUNBALPER;
 219                                 free(result);
 220                                 return (NULL);
 221                         }
 222
 223                         varvalue = get_var(command, nextpercent - command, ifd);
 224
 225                         if (varvalue) {
 226                                 addstr(&result, &len, &pos, varvalue, xstrlen(varvalue));
 227                         } else {
 228                                 okay[opt_depth - 1] = 0;
 229                         }
 230
 231                         command = nextpercent + 1;
 232                 }
 233                         break;
 234                 }
 235         }
 236
 237         if (opt_depth > 1) {
 238                 errno = EUNBALBRACK;
 239                 free(result);
 240                 return(NULL);
 241         }
 242
 243         if (!okay[0]) {
 244                 errno = EUNDEFVAR;
 245                 free(result);
 246                 return(NULL);
 247         }
 248
 249         return(result);
 250 }
 251
 252 static int execute(char *command, interface_defn_t *ifd, execfn *exec)
 253 {
 254         char *out;
 255         int ret;
 256
 257         out = parse(command, ifd);
 258         if (!out) {
 259                 return(0);
 260         }
 261
 262         ret = (*exec) (out);
 263
 264         free(out);
 265         return(ret);
 266 }
 267
 268 #ifdef CONFIG_FEATURE_IFUPDOWN_IPX
 269 static int static_up_ipx(interface_defn_t *ifd, execfn *exec)
 270 {
 271         if (!execute("ipx_interface add %iface% %frame% %netnum%", ifd, exec)) {
 272                 return(0);
 273         }
 274         return(1);
 275 }
 276
 277 static int static_down_ipx(interface_defn_t *ifd, execfn *exec)
 278 {
 279         if (!execute("ipx_interface del %iface% %frame%", ifd, exec)) {
 280                 return(0);
 281         }
 282         return(1);
 283 }
 284
 285 static int dynamic_up(interface_defn_t *ifd, execfn *exec)
 286 {
 287         if (!execute("ipx_interface add %iface% %frame%", ifd, exec)) {
 288                 return(0);
 289         }
 290         return(1);
 291 }
 292
 293 static int dynamic_down(interface_defn_t *ifd, execfn *exec)
 294 {
 295         if (!execute("ipx_interface del %iface% %frame%", ifd, exec)) {
 296                 return(0);
 297         }
 298         return(1);
 299 }
 300
 301 static method_t methods_ipx[] = {
 302         { "dynamic", dynamic_up, dynamic_down, },
 303         { "static", static_up_ipx, static_down_ipx, },
 304 };
 305
 306 address_family_t addr_ipx = {
 307         "ipx",
 308         sizeof(methods_ipx) / sizeof(method_t),
 309         methods_ipx
 310 };
 311 #endif /* IFUP_FEATURE_IPX */
 312
 313 #ifdef CONFIG_FEATURE_IFUPDOWN_IPV6
 314 static int loopback_up6(interface_defn_t *ifd, execfn *exec)
 315 {
 316         if (!execute("ifconfig %iface% add ::1", ifd, exec)) {
 317                 return(0);
 318         }
 319         return(1);
 320 }
 321
 322 static int loopback_down6(interface_defn_t *ifd, execfn *exec)
 323 {
 324         if (!execute("ifconfig %iface% del ::1", ifd, exec)) {
 325                 return(0);
 326         }
 327         return(1);
 328 }
 329
 330 static int static_up6(interface_defn_t *ifd, execfn *exec)
 331 {
 332         if (!execute("ifconfig %iface% [[media %media%]] [[hw %hwaddress%]] [[mtu %mtu%]] up", ifd, exec)) {
 333                 return(0);
 334         }
 335         if (!execute("ifconfig %iface% add %address%/%netmask%", ifd, exec)) {
 336                 return(0);
 337         }
 338         if (!execute("[[ route -A inet6 add ::/0 gw %gateway% ]]", ifd, exec)) {
 339                 return(0);
 340         }
 341         return(1);
 342 }
 343
 344 static int static_down6(interface_defn_t *ifd, execfn *exec)
 345 {
 346         if (!execute("ifconfig %iface% down", ifd, exec)) {
 347                 return(0);
 348         }
 349         return(1);
 350 }
 351
 352 static int v4tunnel_up(interface_defn_t *ifd, execfn *exec)
 353 {
 354         if (!execute("ip tunnel add %iface% mode sit remote %endpoint% [[local %local%]] [[ttl %ttl%]]", ifd, exec)) {
 355                 return(0);
 356         }
 357         if (!execute("ip link set %iface% up", ifd, exec)) {
 358                 return(0);
 359         }
 360         if (!execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec)) {
 361                 return(0);
 362         }
 363         if (!execute("[[ ip route add ::/0 via %gateway% ]]", ifd, exec)) {
 364                 return(0);
 365         }
 366         return(1);
 367 }
 368
 369 static int v4tunnel_down(interface_defn_t * ifd, execfn * exec)
 370 {
 371         if (!execute("ip tunnel del %iface%", ifd, exec)) {
 372                 return(0);
 373         }
 374         return(1);
 375 }
 376
 377 static method_t methods6[] = {
 378         { "v4tunnel", v4tunnel_up, v4tunnel_down, },
 379         { "static", static_up6, static_down6, },
 380         { "loopback", loopback_up6, loopback_down6, },
 381 };
 382
 383 address_family_t addr_inet6 = {
 384         "inet6",
 385         sizeof(methods6) / sizeof(method_t),
 386         methods6
 387 };
 388 #endif /* CONFIG_FEATURE_IFUPDOWN_IPV6 */
 389
 390 #ifdef CONFIG_FEATURE_IFUPDOWN_IPV4
 391 static int loopback_up(interface_defn_t *ifd, execfn *exec)
 392 {
 393         if (!execute("ifconfig %iface% 127.0.0.1 up", ifd, exec)) {
 394                 return(0);
 395         }
 396         return(1);
 397 }
 398
 399 static int loopback_down(interface_defn_t *ifd, execfn *exec)
 400 {
 401         if (!execute("ifconfig %iface% 127.0.0.1 down", ifd, exec)) {
 402                 return(0);
 403         }
 404         return(1);
 405 }
 406
 407 static int static_up(interface_defn_t *ifd, execfn *exec)
 408 {
 409         if (!execute("ifconfig %iface% %address% netmask %netmask% [[broadcast %broadcast%]]    [[pointopoint %pointopoint%]] [[media %media%]] [[mtu %mtu%]]   [[hw %hwaddress%]] up",
 410                  ifd, exec)) {
 411                 return(0);
 412         }
 413         if (!execute("[[ route add default gw %gateway% %iface% ]]", ifd, exec)) {
 414                 return(0);
 415         }
 416         return(1);
 417 }
 418
 419 static int static_down(interface_defn_t *ifd, execfn *exec)
 420 {
 421         if (!execute("[[ route del default gw %gateway% %iface% ]]", ifd, exec)) {
 422                 return(0);
 423         }
 424         if (!execute("ifconfig %iface% down", ifd, exec)) {
 425                 return(0);
 426         }
 427         return(1);
 428 }
 429
 430 static int execable(char *program)
 431 {
 432         struct stat buf;
 433         if (0 == stat(program, &buf)) {
 434                 if (S_ISREG(buf.st_mode) && (S_IXUSR & buf.st_mode)) {
 435                         return(1);
 436                 }
 437         }
 438         return(0);
 439 }
 440
 441 static int dhcp_up(interface_defn_t *ifd, execfn *exec)
 442 {
 443         if (execable("/sbin/dhclient")) {
 444                 if (!execute("dhclient -pf /var/run/dhclient.%iface%.pid %iface%", ifd, exec)) {
 445                         return(0);
 446                 }
 447         } else if (execable("/sbin/pump")) {
 448                 if (!execute("pump -i %iface% [[-h %hostname%]] [[-l %leasehours%]]", ifd, exec)) {
 449                         return(0);
 450                 }
 451         } else if (execable("/sbin/udhcpc")) {
 452                 if (!execute("udhcpc -n -p /var/run/udhcpc.%iface%.pid -i %iface% [[-H %hostname%]] [[-c %clientid%]]", ifd, exec)) {
 453                         return 0;
 454                 }
 455         } else if (execable("/sbin/dhcpcd")) {
 456                 if (!execute("dhcpcd [[-h %hostname%]] [[-i %vendor%]] [[-I %clientid%]] [[-l %leasetime%]] %iface%", ifd, exec)) {
 457                         return(0);
 458                 }
 459         }
 460         return(1);
 461 }
 462
 463 static int dhcp_down(interface_defn_t *ifd, execfn *exec)
 464 {
 465         if (execable("/sbin/dhclient")) {
 466                 if (!execute("kill -9 `cat /var/run/udhcpc.%iface%.pid`", ifd, exec)) {
 467                         return(0);
 468                 }
 469         } else if (execable("/sbin/pump")) {
 470                 if (!execute("pump -i %iface% -k", ifd, exec)) {
 471                         return(0);
 472                 }
 473         } else if (execable("/sbin/udhcpc")) {
 474                 if (!execute("kill -9 `cat /var/run/udhcpc.%iface%.pid`", ifd, exec)) {
 475                         return(0);
 476                 }
 477         } else if (execable("/sbin/dhcpcd")) {
 478                 if (!execute("dhcpcd -k %iface%", ifd, exec)) {
 479                         return(0);
 480                 }
 481         }
 482         if (!execute("ifconfig %iface% down", ifd, exec)) {
 483                 return(0);
 484         }
 485         return(1);
 486 }
 487
 488 static int bootp_up(interface_defn_t *ifd, execfn *exec)
 489 {
 490         if (!execute("bootpc [[--bootfile %bootfile%]] --dev %iface% [[--server %server%]]            [[--hwaddr %hwaddr%]] --returniffail --serverbcast", ifd, exec)) {
 491                 return 0;
 492         }
 493         return 1;
 494 }
 495
 496 static int bootp_down(interface_defn_t *ifd, execfn *exec)
 497 {
 498         if (!execute("ifconfig down %iface%", ifd, exec)) {
 499                 return 0;
 500         }
 501         return 1;
 502 }
 503
 504 static int ppp_up(interface_defn_t *ifd, execfn *exec)
 505 {
 506         if (!execute("pon [[%provider%]]", ifd, exec)) {
 507                 return 0;
 508         }
 509         return 1;
 510 }
 511
 512 static int ppp_down(interface_defn_t *ifd, execfn *exec)
 513 {
 514         if (!execute("poff [[%provider%]]", ifd, exec)) {
 515                 return 0;
 516         }
 517         return 1;
 518 }
 519
 520 static int wvdial_up(interface_defn_t *ifd, execfn *exec)
 521 {
 522         if (!execute("/sbin/start-stop-daemon --start -x /usr/bin/wvdial -p /var/run/wvdial.%iface% -b -m -- [[ %provider% ]]", ifd, exec)) {
 523                 return 0;
 524         }
 525         return 1;
 526 }
 527
 528 static int wvdial_down(interface_defn_t *ifd, execfn *exec)
 529 {
 530         if (!execute ("/sbin/start-stop-daemon --stop -x /usr/bin/wvdial -p /var/run/wvdial.%iface% -s 2", ifd, exec)) {
 531                 return 0;
 532         }
 533         return 1;
 534 }
 535
 536 static method_t methods[] = {
 537         { "wvdial", wvdial_up, wvdial_down, },
 538         { "ppp", ppp_up, ppp_down, },
 539         { "static", static_up, static_down, },
 540         { "bootp", bootp_up, bootp_down, },
 541         { "dhcp", dhcp_up, dhcp_down, },
 542         { "loopback", loopback_up, loopback_down, },
 543 };
 544
 545 address_family_t addr_inet = {
 546         "inet",
 547         sizeof(methods) / sizeof(method_t),
 548         methods
 549 };
 550
 551 #endif  /* ifdef CONFIG_FEATURE_IFUPDOWN_IPV4 */
 552
 553 static char *next_word(char *buf, char *word, int maxlen)
 554 {
 555         if (!buf)
 556                 return NULL;
 557         if (!*buf)
 558                 return NULL;
 559
 560         while (!isspace(*buf) && *buf) {
 561                 if (maxlen-- > 1)
 562                         *word++ = *buf;
 563                 buf++;
 564         }
 565         if (maxlen > 0) {
 566                 *word = '\0';
 567         }
 568
 569         while (isspace(*buf) && *buf) {
 570                 buf++;
 571         }
 572
 573         return buf;
 574 }
 575
 576 static address_family_t *get_address_family(address_family_t *af[], char *name)
 577 {
 578         int i;
 579
 580         for (i = 0; af[i]; i++) {
 581                 if (strcmp(af[i]->name, name) == 0) {
 582                         return af[i];
 583                 }
 584         }
 585         return NULL;
 586 }
 587
 588 static method_t *get_method(address_family_t *af, char *name)
 589 {
 590         int i;
 591
 592         for (i = 0; i < af->n_methods; i++) {
 593                 if (strcmp(af->method[i].name, name) == 0) {
 594                         return &af->method[i];
 595                 }
 596         }
 597         return(NULL);
 598 }
 599
 600 static int duplicate_if(interface_defn_t *ifa, interface_defn_t *ifb)
 601 {
 602         if (strcmp(ifa->iface, ifb->iface) != 0) {
 603                 return(0);
 604         }
 605         if (ifa->address_family != ifb->address_family) {
 606                 return(0);
 607         }
 608         return(1);
 609 }
 610
 611 static interfaces_file_t *read_interfaces(char *filename)
 612 {
 613         interface_defn_t *currif = NULL;
 614         interfaces_file_t *defn;
 615 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
 616         mapping_defn_t *currmap = NULL;
 617 #endif
 618         FILE *f;
 619         char firstword[80];
 620         char *buf = NULL;
 621         char *rest;
 622 //      int line;
 623
 624         enum { NONE, IFACE, MAPPING } currently_processing = NONE;
 625
 626         defn = xmalloc(sizeof(interfaces_file_t));
 627         defn->max_autointerfaces = defn->n_autointerfaces = 0;
 628         defn->autointerfaces = NULL;
 629         defn->mappings = NULL;
 630         defn->ifaces = NULL;
 631         f = fopen(filename, "r");
 632         if (f == NULL) {
 633                 return NULL;
 634         }
 635
 636         while ((buf = get_line_from_file(f)) != NULL) {
 637                 char *end;
 638
 639                 if (buf[0] == '#') {
 640                         continue;
 641                 }
 642                 end = last_char_is(buf, '\n');
 643                 if (end) {
 644                         *end = '\0';
 645                 }
 646                 while ((end = last_char_is(buf, ' ')) != NULL) {
 647                         *end = '\0';
 648                 }
 649                 rest = next_word(buf, firstword, 80);
 650                 if (rest == NULL) {
 651                         continue;       /* blank line */
 652                 }
 653
 654                 if (strcmp(firstword, "mapping") == 0) {
 655 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
 656                         currmap = xmalloc(sizeof(mapping_defn_t));
 657                         currmap->max_matches = 0;
 658                         currmap->n_matches = 0;
 659                         currmap->match = NULL;
 660
 661                         while ((rest = next_word(rest, firstword, 80))) {
 662                                 if (currmap->max_matches == currmap->n_matches) {
 663                                         currmap->max_matches = currmap->max_matches * 2 + 1;
 664                                         currmap->match = xrealloc(currmap->match, sizeof(currmap->match) * currmap->max_matches);
 665                                 }
 666
 667                                 currmap->match[currmap->n_matches++] = xstrdup(firstword);
 668                         }
 669                         currmap->max_mappings = 0;
 670                         currmap->n_mappings = 0;
 671                         currmap->mapping = NULL;
 672                         currmap->script = NULL;
 673                         {
 674                                 mapping_defn_t **where = &defn->mappings;
 675                                 while (*where != NULL) {
 676                                         where = &(*where)->next;
 677                                 }
 678                                 *where = currmap;
 679                                 currmap->next = NULL;
 680                         }
 681 #endif
 682                         currently_processing = MAPPING;
 683                 } else if (strcmp(firstword, "iface") == 0) {
 684                         {
 685                                 char iface_name[80];
 686                                 char address_family_name[80];
 687                                 char method_name[80];
 688                                 address_family_t *addr_fams[] = {
 689 #ifdef CONFIG_FEATURE_IFUPDOWN_IPV4
 690                                         &addr_inet,
 691 #endif
 692 #ifdef CONFIG_FEATURE_IFUPDOWN_IPV6
 693                                         &addr_inet6,
 694 #endif
 695 #ifdef CONFIG_FEATURE_IFUPDOWN_IPX
 696                                         &addr_ipx,
 697 #endif
 698                                         NULL
 699                                 };
 700
 701                                 currif = xmalloc(sizeof(interface_defn_t));
 702
 703                                 rest = next_word(rest, iface_name, 80);
 704                                 rest = next_word(rest, address_family_name, 80);
 705                                 rest = next_word(rest, method_name, 80);
 706
 707                                 if (rest == NULL) {
 708                                         error_msg("too few parameters for line \"%s\"", buf);
 709                                         return NULL;
 710                                 }
 711
 712                                 if (rest[0] != '\0') {
 713                                         error_msg("too many parameters \"%s\"", buf);
 714                                         return NULL;
 715                                 }
 716
 717                                 currif->iface = xstrdup(iface_name);
 718
 719                                 currif->address_family = get_address_family(addr_fams, address_family_name);
 720                                 if (!currif->address_family) {
 721                                         error_msg("unknown address type \"%s\"", buf);
 722                                         return NULL;
 723                                 }
 724
 725                                 currif->method = get_method(currif->address_family, method_name);
 726                                 if (!currif->method) {
 727                                         error_msg("unknown method \"%s\"", buf);
 728                                         return NULL;
 729                                 }
 730
 731                                 currif->automatic = 1;
 732                                 currif->max_options = 0;
 733                                 currif->n_options = 0;
 734                                 currif->option = NULL;
 735
 736
 737                                 {
 738                                         interface_defn_t **where = &defn->ifaces;
 739
 740                                         while (*where != NULL) {
 741                                                 if (duplicate_if(*where, currif)) {
 742                                                         error_msg("duplicate interface \"%s\"", buf);
 743                                                         return NULL;
 744                                                 }
 745                                                 where = &(*where)->next;
 746                                         }
 747
 748                                         *where = currif;
 749                                         currif->next = NULL;
 750                                 }
 751                         }
 752                         currently_processing = IFACE;
 753                 } else if (strcmp(firstword, "auto") == 0) {
 754                         while ((rest = next_word(rest, firstword, 80))) {
 755                                 int i;
 756
 757                                 for (i = 0; i < defn->n_autointerfaces; i++) {
 758                                         if (strcmp(firstword, defn->autointerfaces[i]) == 0) {
 759                                                 perror_msg("interface declared auto twice \"%s\"", buf);
 760                                                 return NULL;
 761                                         }
 762                                 }
 763
 764                                 if (defn->n_autointerfaces == defn->max_autointerfaces) {
 765                                         char **tmp;
 766
 767                                         defn->max_autointerfaces *= 2;
 768                                         defn->max_autointerfaces++;
 769                                         tmp = xrealloc(defn->autointerfaces, sizeof(*tmp) * defn->max_autointerfaces);
 770                                         defn->autointerfaces = tmp;
 771                                 }
 772
 773                                 defn->autointerfaces[defn->n_autointerfaces] = xstrdup(firstword);
 774                                 defn->n_autointerfaces++;
 775                         }
 776                         currently_processing = NONE;
 777                 } else {
 778                         switch (currently_processing) {
 779                         case IFACE:
 780                         {
 781                                 int i;
 782
 783                                 if (xstrlen(rest) == 0) {
 784                                         error_msg("option with empty value \"%s\"", buf);
 785                                         return NULL;
 786                                 }
 787
 788                                 if (strcmp(firstword, "up") != 0
 789                                         && strcmp(firstword, "down") != 0
 790                                         && strcmp(firstword, "pre-up") != 0
 791                                         && strcmp(firstword, "post-down") != 0) {
 792                                         for (i = 0; i < currif->n_options; i++) {
 793                                                 if (strcmp(currif->option[i].name, firstword) == 0) {
 794                                                         error_msg("duplicate option \"%s\"", buf);
 795                                                         return NULL;
 796                                                 }
 797                                         }
 798                                 }
 799                         }
 800                                 if (currif->n_options >= currif->max_options) {
 801                                         variable_t *opt;
 802
 803                                         currif->max_options = currif->max_options + 10;
 804                                         opt = xrealloc(currif->option, sizeof(*opt) * currif->max_options);
 805                                         currif->option = opt;
 806                                 }
 807                                 currif->option[currif->n_options].name = xstrdup(firstword);
 808                                 currif->option[currif->n_options].value = xstrdup(rest);
 809                                 if (!currif->option[currif->n_options].name) {
 810                                         perror(filename);
 811                                         return NULL;
 812                                 }
 813                                 if (!currif->option[currif->n_options].value) {
 814                                         perror(filename);
 815                                         return NULL;
 816                                 }
 817                                 currif->n_options++;
 818                                 break;
 819                         case MAPPING:
 820 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
 821                                 if (strcmp(firstword, "script") == 0) {
 822                                         if (currmap->script != NULL) {
 823                                                 error_msg("duplicate script in mapping \"%s\"", buf);
 824                                                 return NULL;
 825                                         } else {
 826                                                 currmap->script = xstrdup(rest);
 827                                         }
 828                                 } else if (strcmp(firstword, "map") == 0) {
 829                                         if (currmap->max_mappings == currmap->n_mappings) {
 830                                                 currmap->max_mappings = currmap->max_mappings * 2 + 1;
 831                                                 currmap->mapping = xrealloc(currmap->mapping, sizeof(char *) * currmap->max_mappings);
 832                                         }
 833                                         currmap->mapping[currmap->n_mappings] = xstrdup(rest);
 834                                         currmap->n_mappings++;
 835                                 } else {
 836                                         error_msg("misplaced option \"%s\"", buf);
 837                                         return NULL;
 838                                 }
 839 #endif
 840                                 break;
 841                         case NONE:
 842                         default:
 843                                 error_msg("misplaced option \"%s\"", buf);
 844                                 return NULL;
 845                         }
 846                 }
 847         }
 848         if (ferror(f) != 0) {
 849                 perror_msg("%s", filename);
 850                 return NULL;
 851         }
 852         fclose(f);
 853
 854         return defn;
 855 }
 856
 857 static int check(char *str)
 858 {
 859         return (str != NULL);
 860 }
 861
 862 static char *setlocalenv(char *format, char *name, char *value)
 863 {
 864         char *result;
 865         char *here;
 866         char *there;
 867
 868         result = xmalloc(xstrlen(format) + xstrlen(name) + xstrlen(value) + 1);
 869
 870         sprintf(result, format, name, value);
 871
 872         for (here = there = result; *there != '=' && *there; there++) {
 873                 if (*there == '-')
 874                         *there = '_';
 875                 if (isalpha(*there))
 876                         *there = toupper(*there);
 877
 878                 if (isalnum(*there) || *there == '_') {
 879                         *here = *there;
 880                         here++;
 881                 }
 882         }
 883         memmove(here, there, xstrlen(there) + 1);
 884
 885         return result;
 886 }
 887
 888 static void set_environ(interface_defn_t *iface, char *mode)
 889 {
 890         char **environend;
 891         int i;
 892         const int n_env_entries = iface->n_options + 5;
 893         char **ppch;
 894
 895         if (environ != NULL) {
 896                 for (ppch = environ; *ppch; ppch++) {
 897                         free(*ppch);
 898                         *ppch = NULL;
 899                 }
 900                 free(environ);
 901                 environ = NULL;
 902         }
 903         environ = xmalloc(sizeof(char *) * (n_env_entries + 1 /* for final NULL */ ));
 904         environend = environ;
 905         *environend = NULL;
 906
 907         for (i = 0; i < iface->n_options; i++) {
 908                 if (strcmp(iface->option[i].name, "up") == 0
 909                         || strcmp(iface->option[i].name, "down") == 0
 910                         || strcmp(iface->option[i].name, "pre-up") == 0
 911                         || strcmp(iface->option[i].name, "post-down") == 0) {
 912                         continue;
 913                 }
 914                 *(environend++) = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
 915                 *environend = NULL;
 916         }
 917
 918         *(environend++) = setlocalenv("%s=%s", "IFACE", iface->iface);
 919         *environend = NULL;
 920         *(environend++) = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
 921         *environend = NULL;
 922         *(environend++) = setlocalenv("%s=%s", "METHOD", iface->method->name);
 923         *environend = NULL;
 924         *(environend++) = setlocalenv("%s=%s", "MODE", mode);
 925         *environend = NULL;
 926         *(environend++) = setlocalenv("%s=%s", "PATH", "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin");
 927         *environend = NULL;
 928 }
 929
 930 static int doit(char *str)
 931 {
 932         if (verbose || no_act) {
 933                 error_msg("%s", str);
 934         }
 935         if (!no_act) {
 936                 pid_t child;
 937                 int status;
 938
 939                 fflush(NULL);
 940                 switch (child = fork()) {
 941                 case -1:                /* failure */
 942                         return 0;
 943                 case 0:         /* child */
 944                         execle("/bin/sh", "/bin/sh", "-c", str, NULL, environ);
 945                         exit(127);
 946                 default:                /* parent */
 947                 }
 948                 waitpid(child, &status, 0);
 949                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 950                         return 0;
 951                 }
 952         }
 953         return (1);
 954 }
 955
 956 static int execute_all(interface_defn_t *ifd, execfn *exec, const char *opt)
 957 {
 958         int i;
 959         char *buf;
 960
 961         for (i = 0; i < ifd->n_options; i++) {
 962                 if (strcmp(ifd->option[i].name, opt) == 0) {
 963                         if (!(*exec) (ifd->option[i].value)) {
 964                                 return 0;
 965                         }
 966                 }
 967         }
 968
 969         buf = xmalloc(xstrlen(opt) + 19);
 970         sprintf(buf, "/etc/network/if-%s.d", opt);
 971         run_parts(&buf, 0);
 972         free(buf);
 973         return (1);
 974 }
 975
 976 static int iface_up(interface_defn_t *iface)
 977 {
 978         if (!iface->method->up(iface, check)) {
 979                 return (-1);
 980         }
 981
 982         set_environ(iface, "start");
 983         if (!execute_all(iface, doit, "pre-up")) {
 984                 return (0);
 985         }
 986         if (!iface->method->up(iface, doit)) {
 987                 return (0);
 988         }
 989         if (!execute_all(iface, doit, "up")) {
 990                 return (0);
 991         }
 992
 993         return (1);
 994 }
 995
 996 static int iface_down(interface_defn_t *iface)
 997 {
 998         if (!iface->method->down(iface, check)) {
 999                 return (-1);
1000         }
1001         set_environ(iface, "stop");
1002         if (!execute_all(iface, doit, "down")) {
1003                 return (0);
1004         }
1005         if (!iface->method->down(iface, doit)) {
1006                 return (0);
1007         }
1008         if (!execute_all(iface, doit, "post-down")) {
1009                 return (0);
1010         }
1011         return (1);
1012 }
1013
1014 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1015 static int popen2(FILE **in, FILE **out, char *command, ...)
1016 {
1017         va_list ap;
1018         char *argv[11] = { command };
1019         int argc;
1020         int infd[2], outfd[2];
1021         pid_t pid;
1022
1023         argc = 1;
1024         va_start(ap, command);
1025         while ((argc < 10) && (argv[argc] = va_arg(ap, char *))) {
1026                 argc++;
1027         }
1028         argv[argc] = NULL;      /* make sure */
1029         va_end(ap);
1030
1031         if (pipe(infd) != 0) {
1032                 return 0;
1033         }
1034
1035         if (pipe(outfd) != 0) {
1036                 close(infd[0]);
1037                 close(infd[1]);
1038                 return 0;
1039         }
1040
1041         fflush(NULL);
1042         switch (pid = fork()) {
1043         case -1:                        /* failure */
1044                 close(infd[0]);
1045                 close(infd[1]);
1046                 close(outfd[0]);
1047                 close(outfd[1]);
1048                 return 0;
1049         case 0:                 /* child */
1050                 dup2(infd[0], 0);
1051                 dup2(outfd[1], 1);
1052                 close(infd[0]);
1053                 close(infd[1]);
1054                 close(outfd[0]);
1055                 close(outfd[1]);
1056                 execvp(command, argv);
1057                 exit(127);
1058         default:                        /* parent */
1059                 *in = fdopen(infd[1], "w");
1060                 *out = fdopen(outfd[0], "r");
1061                 close(infd[0]);
1062                 close(outfd[1]);
1063                 return pid;
1064         }
1065         /* unreached */
1066 }
1067
1068 static int run_mapping(char *physical, char *logical, int len, mapping_defn_t * map)
1069 {
1070         FILE *in, *out;
1071         int i, status;
1072         pid_t pid;
1073
1074
1075         pid = popen2(&in, &out, map->script, physical, NULL);
1076         if (pid == 0) {
1077                 return 0;
1078         }
1079         for (i = 0; i < map->n_mappings; i++) {
1080                 fprintf(in, "%s\n", map->mapping[i]);
1081         }
1082         fclose(in);
1083         waitpid(pid, &status, 0);
1084         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
1085                 if (fgets(logical, len, out)) {
1086                         char *pch = logical + xstrlen(logical) - 1;
1087
1088                         while (pch >= logical && isspace(*pch))
1089                                 *(pch--) = '\0';
1090                 }
1091         }
1092         fclose(out);
1093
1094         return 1;
1095 }
1096 #endif /* CONFIG_FEATURE_IFUPDOWN_IPV6 */
1097
1098 static int lookfor_iface(char **ifaces, int n_ifaces, char *iface)
1099 {
1100         int i;
1101
1102         for (i = 0; i < n_ifaces; i++) {
1103                 if (strncmp(iface, ifaces[i], xstrlen(iface)) == 0) {
1104                         if (ifaces[i][xstrlen(iface)] == '=') {
1105                                 return i;
1106                         }
1107                 }
1108         }
1109
1110         return(-1);
1111 }
1112
1113 static void add_to_state(char ***ifaces, int *n_ifaces, int *max_ifaces, char *new_iface)
1114 {
1115         if (*max_ifaces == *n_ifaces) {
1116                 *max_ifaces = (*max_ifaces * 2) + 1;
1117                 *ifaces = xrealloc(*ifaces, sizeof(**ifaces) * *max_ifaces);
1118         }
1119
1120         (*ifaces)[(*n_ifaces)++] = new_iface;
1121 }
1122
1123 extern int ifupdown_main(int argc, char **argv)
1124 {
1125         int (*cmds) (interface_defn_t *) = NULL;
1126         interfaces_file_t *defn;
1127         FILE *state_fp = NULL;
1128         char **target_iface = NULL;
1129         char **state = NULL;    /* list of iface=liface */
1130         char *interfaces = "/etc/network/interfaces";
1131         char *statefile = "/var/run/ifstate";
1132
1133 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1134         int run_mappings = 1;
1135 #endif
1136         int do_all = 0;
1137         int force = 0;
1138         int n_target_ifaces = 0;
1139         int n_state = 0;
1140         int max_state = 0;
1141         int i;
1142
1143         if (applet_name[2] == 'u') {
1144                 /* ifup command */
1145                 cmds = iface_up;
1146         } else {
1147                 /* ifdown command */
1148                 cmds = iface_down;
1149         }
1150
1151 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1152         while ((i = getopt(argc, argv, "i:hvnamf")) != -1) {
1153 #else
1154         while ((i = getopt(argc, argv, "i:hvnaf")) != -1) {
1155 #endif
1156                 switch (i) {
1157                 case 'i':       /* interfaces */
1158                         interfaces = xstrdup(optarg);
1159                         break;
1160                 case 'v':       /* verbose */
1161                         verbose = 1;
1162                         break;
1163                 case 'a':       /* all */
1164                         do_all = 1;
1165                         break;
1166                 case 'n':       /* no-act */
1167                         no_act = 1;
1168                         break;
1169 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1170                 case 'm':       /* no-mappings */
1171                         run_mappings = 0;
1172                         break;
1173 #endif
1174                 case 'f':       /* force */
1175                         force = 1;
1176                         break;
1177                 default:
1178                         show_usage();
1179                         break;
1180                 }
1181         }
1182
1183         if (argc - optind > 0) {
1184                 if (do_all) {
1185                         show_usage();
1186                 }
1187         } else {
1188                 if (!do_all) {
1189                         show_usage();
1190                 }
1191         }
1192
1193         defn = read_interfaces(interfaces);
1194         if (!defn) {
1195                 error_msg_and_die("couldn't read interfaces file \"%s\"", interfaces);
1196         }
1197
1198         state_fp = fopen(statefile, no_act ? "r" : "a+");
1199         if (state_fp == NULL && !no_act) {
1200                 perror_msg_and_die("failed to open statefile %s", statefile);
1201         }
1202
1203         if (state_fp != NULL) {
1204                 char *start;
1205                 while ((start = get_line_from_file(state_fp)) != NULL) {
1206                         char *end_ptr;
1207                         /* We should only need to check for a single character */
1208                         end_ptr = start + strcspn(start, " \t\n");
1209                         *end_ptr = '\0';
1210                         add_to_state(&state, &n_state, &max_state, start);
1211                 }
1212         }
1213
1214         if (do_all) {
1215                 if (cmds == iface_up) {
1216                         target_iface = defn->autointerfaces;
1217                         n_target_ifaces = defn->n_autointerfaces;
1218                 } else if (cmds == iface_down) {
1219                         target_iface = state;
1220                         n_target_ifaces = n_state;
1221                 }
1222         } else {
1223                 target_iface = argv + optind;
1224                 n_target_ifaces = argc - optind;
1225         }
1226
1227
1228         for (i = 0; i < n_target_ifaces; i++) {
1229                 interface_defn_t *currif;
1230                 char iface[80];
1231                 char liface[80];
1232                 char *pch;
1233                 int okay = 0;
1234
1235                 strncpy(iface, target_iface[i], sizeof(iface));
1236                 iface[sizeof(iface) - 1] = '\0';
1237
1238                 if ((pch = strchr(iface, '='))) {
1239                         *pch = '\0';
1240                         strncpy(liface, pch + 1, sizeof(liface));
1241                         liface[sizeof(liface) - 1] = '\0';
1242                 } else {
1243                         strncpy(liface, iface, sizeof(liface));
1244                         liface[sizeof(liface) - 1] = '\0';
1245                 }
1246                 if (!force) {
1247                         int already_up = lookfor_iface(state, n_state, iface);;
1248
1249                         if (cmds == iface_up) {
1250                                 /* ifup */
1251                                 if (already_up != -1) {
1252                                         error_msg("interface %s already configured", iface);
1253                                         continue;
1254                                 }
1255                         } else {
1256                                 /* ifdown */
1257                                 if (already_up == -1) {
1258                                         error_msg("interface %s not configured", iface);
1259                                         continue;
1260                                 }
1261                                 strncpy(liface, strchr(state[already_up], '=') + 1, 80);
1262                                 liface[79] = 0;
1263                         }
1264                 }
1265 #ifdef CONFIG_FEATURE_IFUPDOWN_MAPPING
1266                 if ((cmds == iface_up) && run_mappings) {
1267                         mapping_defn_t *currmap;
1268
1269                         for (currmap = defn->mappings; currmap; currmap = currmap->next) {
1270
1271                                 for (i = 0; i < currmap->n_matches; i++) {
1272                                         if (fnmatch(currmap->match[i], liface, 0) != 0)
1273                                                 continue;
1274                                         if (verbose) {
1275                                                 error_msg("Running mapping script %s on %s", currmap->script, liface);
1276                                         }
1277                                         run_mapping(iface, liface, sizeof(liface), currmap);
1278                                         break;
1279                                 }
1280                         }
1281                 }
1282 #endif
1283
1284                 for (currif = defn->ifaces; currif; currif = currif->next) {
1285                         if (strcmp(liface, currif->iface) == 0) {
1286                                 char *oldiface = currif->iface;
1287
1288                                 okay = 1;
1289
1290                                 currif->iface = iface;
1291
1292                                 if (verbose) {
1293                                         error_msg("Configuring interface %s=%s (%s)", iface, liface, currif->address_family->name);
1294                                 }
1295
1296                                 if (cmds(currif) == -1) {
1297                                         printf
1298                                                 ("Don't seem to be have all the variables for %s/%s.\n",
1299                                                  liface, currif->address_family->name);
1300                                 }
1301
1302                                 currif->iface = oldiface;
1303                         }
1304                 }
1305
1306                 if (!okay && !force) {
1307                         error_msg("Ignoring unknown interface %s=%s.", iface, liface);
1308                 } else {
1309                         int already_up = lookfor_iface(state, n_state, iface);
1310
1311                         if (cmds == iface_up) {
1312                                 char *newiface = xmalloc(xstrlen(iface) + 1 + xstrlen(liface) + 1);
1313                                 sprintf(newiface, "%s=%s", iface, liface);
1314                                 if (already_up == -1) {
1315                                         add_to_state(&state, &n_state, &max_state, newiface);
1316                                 } else {
1317                                         free(state[already_up]);
1318                                         state[already_up] = newiface;
1319                                 }
1320                         } else if (cmds == iface_down) {
1321                                 if (already_up != -1) {
1322                                         state[already_up] = state[--n_state];
1323                                 }
1324                         }
1325                 }
1326                 if (state_fp != NULL && !no_act) {
1327                         unsigned short j;
1328
1329                         if (ftruncate(fileno(state_fp), 0) < 0) {
1330                                 error_msg_and_die("failed to truncate statefile %s: %s", statefile, strerror(errno));
1331                         }
1332
1333                         rewind(state_fp);
1334                         for (j = 0; j < n_state; j++) {
1335                                 fputs(state[i], state_fp);
1336                                 fputc('\n', state_fp);
1337                         }
1338                         fflush(state_fp);
1339                 }
1340         }
1341
1342         if (state_fp != NULL) {
1343                 fclose(state_fp);
1344                 state_fp = NULL;
1345         }
1346
1347         return 0;
1348 }