vcs.maemo.org Git - busybox4maemo/blob - networking/ifupdown.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  *  ifupdown for busybox
   4  *  Copyright (c) 2002 Glenn McGrath
   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  *  (defined via CONFIG_IFUPDOWN_IFSTATE_PATH) and can be overridden by build
  15  *  configuration.
  16  *
  17  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  18  */
  19
  20 #include <sys/utsname.h>
  21 #include <fnmatch.h>
  22 #include <getopt.h>
  23
  24 #include "libbb.h"
  25
  26 #define MAX_OPT_DEPTH 10
  27 #define EUNBALBRACK 10001
  28 #define EUNDEFVAR   10002
  29 #define EUNBALPER   10000
  30
  31 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
  32 #define MAX_INTERFACE_LENGTH 10
  33 #endif
  34
  35 #define debug_noise(args...) /*fprintf(stderr, args)*/
  36
  37 /* Forward declaration */
  38 struct interface_defn_t;
  39
  40 typedef int execfn(char *command);
  41
  42 struct method_t {
  43         const char *name;
  44         int (*up)(struct interface_defn_t *ifd, execfn *e);
  45         int (*down)(struct interface_defn_t *ifd, execfn *e);
  46 };
  47
  48 struct address_family_t {
  49         const char *name;
  50         int n_methods;
  51         const struct method_t *method;
  52 };
  53
  54 struct mapping_defn_t {
  55         struct mapping_defn_t *next;
  56
  57         int max_matches;
  58         int n_matches;
  59         char **match;
  60
  61         char *script;
  62
  63         int max_mappings;
  64         int n_mappings;
  65         char **mapping;
  66 };
  67
  68 struct variable_t {
  69         char *name;
  70         char *value;
  71 };
  72
  73 struct interface_defn_t {
  74         const struct address_family_t *address_family;
  75         const struct method_t *method;
  76
  77         char *iface;
  78         int max_options;
  79         int n_options;
  80         struct variable_t *option;
  81 };
  82
  83 struct interfaces_file_t {
  84         llist_t *autointerfaces;
  85         llist_t *ifaces;
  86         struct mapping_defn_t *mappings;
  87 };
  88
  89 #define OPTION_STR "anvf" USE_FEATURE_IFUPDOWN_MAPPING("m") "i:"
  90 enum {
  91         OPT_do_all = 0x1,
  92         OPT_no_act = 0x2,
  93         OPT_verbose = 0x4,
  94         OPT_force = 0x8,
  95         OPT_no_mappings = 0x10,
  96 };
  97 #define DO_ALL (option_mask32 & OPT_do_all)
  98 #define NO_ACT (option_mask32 & OPT_no_act)
  99 #define VERBOSE (option_mask32 & OPT_verbose)
 100 #define FORCE (option_mask32 & OPT_force)
 101 #define NO_MAPPINGS (option_mask32 & OPT_no_mappings)
 102
 103 static char **my_environ;
 104
 105 static const char *startup_PATH;
 106
 107 #if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
 108
 109 static void addstr(char **bufp, const char *str, size_t str_length)
 110 {
 111         /* xasprintf trick will be smaller, but we are often
 112          * called with str_length == 1 - don't want to have
 113          * THAT much of malloc/freeing! */
 114         char *buf = *bufp;
 115         int len = (buf ? strlen(buf) : 0);
 116         str_length++;
 117         buf = xrealloc(buf, len + str_length);
 118         /* copies at most str_length-1 chars! */
 119         safe_strncpy(buf + len, str, str_length);
 120         *bufp = buf;
 121 }
 122
 123 static int strncmpz(const char *l, const char *r, size_t llen)
 124 {
 125         int i = strncmp(l, r, llen);
 126
 127         if (i == 0)
 128                 return -r[llen];
 129         return i;
 130 }
 131
 132 static char *get_var(const char *id, size_t idlen, struct interface_defn_t *ifd)
 133 {
 134         int i;
 135
 136         if (strncmpz(id, "iface", idlen) == 0) {
 137                 static char *label_buf;
 138                 //char *result;
 139
 140                 free(label_buf);
 141                 label_buf = xstrdup(ifd->iface);
 142                 // Remove virtual iface suffix - why?
 143                 // ubuntu's ifup doesn't do this
 144                 //result = strchrnul(label_buf, ':');
 145                 //*result = '\0';
 146                 return label_buf;
 147         }
 148         if (strncmpz(id, "label", idlen) == 0) {
 149                 return ifd->iface;
 150         }
 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         return NULL;
 157 }
 158
 159 #if ENABLE_FEATURE_IFUPDOWN_IP
 160 static int count_netmask_bits(const char *dotted_quad)
 161 {
 162 //      int result;
 163 //      unsigned a, b, c, d;
 164 //      /* Found a netmask...  Check if it is dotted quad */
 165 //      if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
 166 //              return -1;
 167 //      if ((a|b|c|d) >> 8)
 168 //              return -1; /* one of numbers is >= 256 */
 169 //      d |= (a << 24) | (b << 16) | (c << 8); /* IP */
 170 //      d = ~d; /* 11110000 -> 00001111 */
 171
 172         /* Shorter version */
 173         int result;
 174         struct in_addr ip;
 175         unsigned d;
 176
 177         if (inet_aton(dotted_quad, &ip) == 0)
 178                 return -1; /* malformed dotted IP */
 179         d = ntohl(ip.s_addr); /* IP in host order */
 180         d = ~d; /* 11110000 -> 00001111 */
 181         if (d & (d+1)) /* check that it is in 00001111 form */
 182                 return -1; /* no it is not */
 183         result = 32;
 184         while (d) {
 185                 d >>= 1;
 186                 result--;
 187         }
 188         return result;
 189 }
 190 #endif
 191
 192 static char *parse(const char *command, struct interface_defn_t *ifd)
 193 {
 194         size_t old_pos[MAX_OPT_DEPTH] = { 0 };
 195         int okay[MAX_OPT_DEPTH] = { 1 };
 196         int opt_depth = 1;
 197         char *result = NULL;
 198
 199         while (*command) {
 200                 switch (*command) {
 201                 default:
 202                         addstr(&result, command, 1);
 203                         command++;
 204                         break;
 205                 case '\\':
 206                         if (command[1]) {
 207                                 addstr(&result, command + 1, 1);
 208                                 command += 2;
 209                         } else {
 210                                 addstr(&result, command, 1);
 211                                 command++;
 212                         }
 213                         break;
 214                 case '[':
 215                         if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
 216                                 old_pos[opt_depth] = result ? strlen(result) : 0;
 217                                 okay[opt_depth] = 1;
 218                                 opt_depth++;
 219                                 command += 2;
 220                         } else {
 221                                 addstr(&result, "[", 1);
 222                                 command++;
 223                         }
 224                         break;
 225                 case ']':
 226                         if (command[1] == ']' && opt_depth > 1) {
 227                                 opt_depth--;
 228                                 if (!okay[opt_depth]) {
 229                                         result[old_pos[opt_depth]] = '\0';
 230                                 }
 231                                 command += 2;
 232                         } else {
 233                                 addstr(&result, "]", 1);
 234                                 command++;
 235                         }
 236                         break;
 237                 case '%':
 238                         {
 239                                 char *nextpercent;
 240                                 char *varvalue;
 241
 242                                 command++;
 243                                 nextpercent = strchr(command, '%');
 244                                 if (!nextpercent) {
 245                                         errno = EUNBALPER;
 246                                         free(result);
 247                                         return NULL;
 248                                 }
 249
 250                                 varvalue = get_var(command, nextpercent - command, ifd);
 251
 252                                 if (varvalue) {
 253                                         addstr(&result, varvalue, strlen(varvalue));
 254                                 } else {
 255 #if ENABLE_FEATURE_IFUPDOWN_IP
 256                                         /* Sigh...  Add a special case for 'ip' to convert from
 257                                          * dotted quad to bit count style netmasks.  */
 258                                         if (strncmp(command, "bnmask", 6) == 0) {
 259                                                 unsigned res;
 260                                                 varvalue = get_var("netmask", 7, ifd);
 261                                                 if (varvalue) {
 262                                                         res = count_netmask_bits(varvalue);
 263                                                         if (res > 0) {
 264                                                                 const char *argument = utoa(res);
 265                                                                 addstr(&result, argument, strlen(argument));
 266                                                                 command = nextpercent + 1;
 267                                                                 break;
 268                                                         }
 269                                                 }
 270                                         }
 271 #endif
 272                                         okay[opt_depth - 1] = 0;
 273                                 }
 274
 275                                 command = nextpercent + 1;
 276                         }
 277                         break;
 278                 }
 279         }
 280
 281         if (opt_depth > 1) {
 282                 errno = EUNBALBRACK;
 283                 free(result);
 284                 return NULL;
 285         }
 286
 287         if (!okay[0]) {
 288                 errno = EUNDEFVAR;
 289                 free(result);
 290                 return NULL;
 291         }
 292
 293         return result;
 294 }
 295
 296 /* execute() returns 1 for success and 0 for failure */
 297 static int execute(const 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                 /* parse error? */
 305                 return 0;
 306         }
 307         /* out == "": parsed ok but not all needed variables known, skip */
 308         ret = out[0] ? (*exec)(out) : 1;
 309
 310         free(out);
 311         if (ret != 1) {
 312                 return 0;
 313         }
 314         return 1;
 315 }
 316 #endif
 317
 318 #if ENABLE_FEATURE_IFUPDOWN_IPV6
 319 static int loopback_up6(struct interface_defn_t *ifd, execfn *exec)
 320 {
 321 #if ENABLE_FEATURE_IFUPDOWN_IP
 322         int result;
 323         result = execute("ip addr add ::1 dev %iface%", ifd, exec);
 324         result += execute("ip link set %iface% up", ifd, exec);
 325         return ((result == 2) ? 2 : 0);
 326 #else
 327         return execute("ifconfig %iface% add ::1", ifd, exec);
 328 #endif
 329 }
 330
 331 static int loopback_down6(struct interface_defn_t *ifd, execfn *exec)
 332 {
 333 #if ENABLE_FEATURE_IFUPDOWN_IP
 334         return execute("ip link set %iface% down", ifd, exec);
 335 #else
 336         return execute("ifconfig %iface% del ::1", ifd, exec);
 337 #endif
 338 }
 339
 340 static int static_up6(struct interface_defn_t *ifd, execfn *exec)
 341 {
 342         int result;
 343 #if ENABLE_FEATURE_IFUPDOWN_IP
 344         result = execute("ip addr add %address%/%netmask% dev %iface%[[ label %label%]]", ifd, exec);
 345         result += execute("ip link set[[ mtu %mtu%]][[ address %hwaddress%]] %iface% up", ifd, exec);
 346         /* Was: "[[ ip ....%gateway% ]]". Removed extra spaces w/o checking */
 347         result += execute("[[ip route add ::/0 via %gateway%]]", ifd, exec);
 348 #else
 349         result = execute("ifconfig %iface%[[ media %media%]][[ hw %hwaddress%]][[ mtu %mtu%]] up", ifd, exec);
 350         result += execute("ifconfig %iface% add %address%/%netmask%", ifd, exec);
 351         result += execute("[[route -A inet6 add ::/0 gw %gateway%]]", ifd, exec);
 352 #endif
 353         return ((result == 3) ? 3 : 0);
 354 }
 355
 356 static int static_down6(struct interface_defn_t *ifd, execfn *exec)
 357 {
 358 #if ENABLE_FEATURE_IFUPDOWN_IP
 359         return execute("ip link set %iface% down", ifd, exec);
 360 #else
 361         return execute("ifconfig %iface% down", ifd, exec);
 362 #endif
 363 }
 364
 365 #if ENABLE_FEATURE_IFUPDOWN_IP
 366 static int v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
 367 {
 368         int result;
 369         result = execute("ip tunnel add %iface% mode sit remote "
 370                         "%endpoint%[[ local %local%]][[ ttl %ttl%]]", ifd, exec);
 371         result += execute("ip link set %iface% up", ifd, exec);
 372         result += execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec);
 373         result += execute("[[ip route add ::/0 via %gateway%]]", ifd, exec);
 374         return ((result == 4) ? 4 : 0);
 375 }
 376
 377 static int v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
 378 {
 379         return execute("ip tunnel del %iface%", ifd, exec);
 380 }
 381 #endif
 382
 383 static const struct method_t methods6[] = {
 384 #if ENABLE_FEATURE_IFUPDOWN_IP
 385         { "v4tunnel", v4tunnel_up, v4tunnel_down, },
 386 #endif
 387         { "static", static_up6, static_down6, },
 388         { "loopback", loopback_up6, loopback_down6, },
 389 };
 390
 391 static const struct address_family_t addr_inet6 = {
 392         "inet6",
 393         ARRAY_SIZE(methods6),
 394         methods6
 395 };
 396 #endif /* FEATURE_IFUPDOWN_IPV6 */
 397
 398 #if ENABLE_FEATURE_IFUPDOWN_IPV4
 399 static int loopback_up(struct interface_defn_t *ifd, execfn *exec)
 400 {
 401 #if ENABLE_FEATURE_IFUPDOWN_IP
 402         int result;
 403         result = execute("ip addr add 127.0.0.1/8 dev %iface%", ifd, exec);
 404         result += execute("ip link set %iface% up", ifd, exec);
 405         return ((result == 2) ? 2 : 0);
 406 #else
 407         return execute("ifconfig %iface% 127.0.0.1 up", ifd, exec);
 408 #endif
 409 }
 410
 411 static int loopback_down(struct interface_defn_t *ifd, execfn *exec)
 412 {
 413 #if ENABLE_FEATURE_IFUPDOWN_IP
 414         int result;
 415         result = execute("ip addr flush dev %iface%", ifd, exec);
 416         result += execute("ip link set %iface% down", ifd, exec);
 417         return ((result == 2) ? 2 : 0);
 418 #else
 419         return execute("ifconfig %iface% 127.0.0.1 down", ifd, exec);
 420 #endif
 421 }
 422
 423 static int static_up(struct interface_defn_t *ifd, execfn *exec)
 424 {
 425         int result;
 426 #if ENABLE_FEATURE_IFUPDOWN_IP
 427         result = execute("ip addr add %address%/%bnmask%[[ broadcast %broadcast%]] "
 428                         "dev %iface%[[ peer %pointopoint%]][[ label %label%]]", ifd, exec);
 429         result += execute("ip link set[[ mtu %mtu%]][[ address %hwaddress%]] %iface% up", ifd, exec);
 430         result += execute("[[ip route add default via %gateway% dev %iface%]]", ifd, exec);
 431         return ((result == 3) ? 3 : 0);
 432 #else
 433         /* ifconfig said to set iface up before it processes hw %hwaddress%,
 434          * which then of course fails. Thus we run two separate ifconfig */
 435         result = execute("ifconfig %iface%[[ hw %hwaddress%]][[ media %media%]][[ mtu %mtu%]] up",
 436                                 ifd, exec);
 437         result += execute("ifconfig %iface% %address% netmask %netmask%"
 438                                 "[[ broadcast %broadcast%]][[ pointopoint %pointopoint%]] ",
 439                                 ifd, exec);
 440         result += execute("[[route add default gw %gateway% %iface%]]", ifd, exec);
 441         return ((result == 3) ? 3 : 0);
 442 #endif
 443 }
 444
 445 static int static_down(struct interface_defn_t *ifd, execfn *exec)
 446 {
 447         int result;
 448 #if ENABLE_FEATURE_IFUPDOWN_IP
 449         result = execute("ip addr flush dev %iface%", ifd, exec);
 450         result += execute("ip link set %iface% down", ifd, exec);
 451 #else
 452         result = execute("[[route del default gw %gateway% %iface%]]", ifd, exec);
 453         result += execute("ifconfig %iface% down", ifd, exec);
 454 #endif
 455         return ((result == 2) ? 2 : 0);
 456 }
 457
 458 #if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 459 struct dhcp_client_t
 460 {
 461         const char *name;
 462         const char *startcmd;
 463         const char *stopcmd;
 464 };
 465
 466 static const struct dhcp_client_t ext_dhcp_clients[] = {
 467         { "dhcpcd",
 468                 "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %clientid%]][[ -l %leasetime%]] %iface%",
 469                 "dhcpcd -k %iface%",
 470         },
 471         { "dhclient",
 472                 "dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
 473                 "kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
 474         },
 475         { "pump",
 476                 "pump -i %iface%[[ -h %hostname%]][[ -l %leasehours%]]",
 477                 "pump -i %iface% -k",
 478         },
 479         { "udhcpc",
 480                 "udhcpc -R -n -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
 481                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
 482         },
 483 };
 484 #endif /* ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
 485
 486 #if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 487 static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 488 {
 489         int i;
 490 #if ENABLE_FEATURE_IFUPDOWN_IP
 491         /* ip doesn't up iface when it configures it (unlike ifconfig) */
 492         if (!execute("ip link set %iface% up", ifd, exec))
 493                 return 0;
 494 #endif
 495         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
 496                 if (exists_execable(ext_dhcp_clients[i].name))
 497                         return execute(ext_dhcp_clients[i].startcmd, ifd, exec);
 498         }
 499         bb_error_msg("no dhcp clients found");
 500         return 0;
 501 }
 502 #elif ENABLE_APP_UDHCPC
 503 static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 504 {
 505 #if ENABLE_FEATURE_IFUPDOWN_IP
 506         /* ip doesn't up iface when it configures it (unlike ifconfig) */
 507         if (!execute("ip link set %iface% up", ifd, exec))
 508                 return 0;
 509 #endif
 510         return execute("udhcpc -R -n -p /var/run/udhcpc.%iface%.pid "
 511                         "-i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
 512                         ifd, exec);
 513 }
 514 #else
 515 static int dhcp_up(struct interface_defn_t *ifd ATTRIBUTE_UNUSED,
 516                 execfn *exec ATTRIBUTE_UNUSED)
 517 {
 518         return 0; /* no dhcp support */
 519 }
 520 #endif
 521
 522 #if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 523 static int dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 524 {
 525         int i;
 526         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
 527                 if (exists_execable(ext_dhcp_clients[i].name))
 528                         return execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
 529         }
 530         bb_error_msg("no dhcp clients found, using static interface shutdown");
 531         return static_down(ifd, exec);
 532 }
 533 #elif ENABLE_APP_UDHCPC
 534 static int dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 535 {
 536         return execute("kill "
 537                        "`cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec);
 538 }
 539 #else
 540 static int dhcp_down(struct interface_defn_t *ifd ATTRIBUTE_UNUSED,
 541                 execfn *exec ATTRIBUTE_UNUSED)
 542 {
 543         return 0; /* no dhcp support */
 544 }
 545 #endif
 546
 547 static int manual_up_down(struct interface_defn_t *ifd ATTRIBUTE_UNUSED, execfn *exec ATTRIBUTE_UNUSED)
 548 {
 549         return 1;
 550 }
 551
 552 static int bootp_up(struct interface_defn_t *ifd, execfn *exec)
 553 {
 554         return execute("bootpc[[ --bootfile %bootfile%]] --dev %iface%"
 555                         "[[ --server %server%]][[ --hwaddr %hwaddr%]]"
 556                         " --returniffail --serverbcast", ifd, exec);
 557 }
 558
 559 static int ppp_up(struct interface_defn_t *ifd, execfn *exec)
 560 {
 561         return execute("pon[[ %provider%]]", ifd, exec);
 562 }
 563
 564 static int ppp_down(struct interface_defn_t *ifd, execfn *exec)
 565 {
 566         return execute("poff[[ %provider%]]", ifd, exec);
 567 }
 568
 569 static int wvdial_up(struct interface_defn_t *ifd, execfn *exec)
 570 {
 571         return execute("start-stop-daemon --start -x wvdial "
 572                 "-p /var/run/wvdial.%iface% -b -m --[[ %provider%]]", ifd, exec);
 573 }
 574
 575 static int wvdial_down(struct interface_defn_t *ifd, execfn *exec)
 576 {
 577         return execute("start-stop-daemon --stop -x wvdial "
 578                         "-p /var/run/wvdial.%iface% -s 2", ifd, exec);
 579 }
 580
 581 static const struct method_t methods[] = {
 582         { "manual", manual_up_down, manual_up_down, },
 583         { "wvdial", wvdial_up, wvdial_down, },
 584         { "ppp", ppp_up, ppp_down, },
 585         { "static", static_up, static_down, },
 586         { "bootp", bootp_up, static_down, },
 587         { "dhcp", dhcp_up, dhcp_down, },
 588         { "loopback", loopback_up, loopback_down, },
 589 };
 590
 591 static const struct address_family_t addr_inet = {
 592         "inet",
 593         ARRAY_SIZE(methods),
 594         methods
 595 };
 596
 597 #endif  /* if ENABLE_FEATURE_IFUPDOWN_IPV4 */
 598
 599 static char *next_word(char **buf)
 600 {
 601         unsigned length;
 602         char *word;
 603
 604         /* Skip over leading whitespace */
 605         word = skip_whitespace(*buf);
 606
 607         /* Stop on EOL */
 608         if (*word == '\0')
 609                 return NULL;
 610
 611         /* Find the length of this word (can't be 0) */
 612         length = strcspn(word, " \t\n");
 613
 614         /* Unless we are already at NUL, store NUL and advance */
 615         if (word[length] != '\0')
 616                 word[length++] = '\0';
 617
 618         *buf = word + length;
 619
 620         return word;
 621 }
 622
 623 static const struct address_family_t *get_address_family(const struct address_family_t *const af[], char *name)
 624 {
 625         int i;
 626
 627         if (!name)
 628                 return NULL;
 629
 630         for (i = 0; af[i]; i++) {
 631                 if (strcmp(af[i]->name, name) == 0) {
 632                         return af[i];
 633                 }
 634         }
 635         return NULL;
 636 }
 637
 638 static const struct method_t *get_method(const struct address_family_t *af, char *name)
 639 {
 640         int i;
 641
 642         if (!name)
 643                 return NULL;
 644         /* TODO: use index_in_str_array() */
 645         for (i = 0; i < af->n_methods; i++) {
 646                 if (strcmp(af->method[i].name, name) == 0) {
 647                         return &af->method[i];
 648                 }
 649         }
 650         return NULL;
 651 }
 652
 653 static const llist_t *find_list_string(const llist_t *list, const char *string)
 654 {
 655         if (string == NULL)
 656                 return NULL;
 657
 658         while (list) {
 659                 if (strcmp(list->data, string) == 0) {
 660                         return list;
 661                 }
 662                 list = list->link;
 663         }
 664         return NULL;
 665 }
 666
 667 static struct interfaces_file_t *read_interfaces(const char *filename)
 668 {
 669         /* Let's try to be compatible.
 670          *
 671          * "man 5 interfaces" says:
 672          * Lines starting with "#" are ignored. Note that end-of-line
 673          * comments are NOT supported, comments must be on a line of their own.
 674          * A line may be extended across multiple lines by making
 675          * the last character a backslash.
 676          *
 677          * Seen elsewhere in example config file:
 678          * A "#" character in the very first column makes the rest of the line
 679          * be ignored. Blank lines are ignored. Lines may be indented freely.
 680          * A "\" character at the very end of the line indicates the next line
 681          * should be treated as a continuation of the current one.
 682          */
 683 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 684         struct mapping_defn_t *currmap = NULL;
 685 #endif
 686         struct interface_defn_t *currif = NULL;
 687         struct interfaces_file_t *defn;
 688         FILE *f;
 689         char *buf;
 690         char *first_word;
 691         char *rest_of_line;
 692         enum { NONE, IFACE, MAPPING } currently_processing = NONE;
 693
 694         defn = xzalloc(sizeof(*defn));
 695         f = xfopen(filename, "r");
 696
 697         while ((buf = xmalloc_getline(f)) != NULL) {
 698 #if ENABLE_DESKTOP
 699                 /* Trailing "\" concatenates lines */
 700                 char *p;
 701                 while ((p = last_char_is(buf, '\\')) != NULL) {
 702                         *p = '\0';
 703                         rest_of_line = xmalloc_getline(f);
 704                         if (!rest_of_line)
 705                                 break;
 706                         p = xasprintf("%s%s", buf, rest_of_line);
 707                         free(buf);
 708                         free(rest_of_line);
 709                         buf = p;
 710                 }
 711 #endif
 712                 rest_of_line = buf;
 713                 first_word = next_word(&rest_of_line);
 714                 if (!first_word || *buf == '#') {
 715                         free(buf);
 716                         continue; /* blank/comment line */
 717                 }
 718
 719                 if (strcmp(first_word, "mapping") == 0) {
 720 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 721                         currmap = xzalloc(sizeof(*currmap));
 722
 723                         while ((first_word = next_word(&rest_of_line)) != NULL) {
 724                                 if (currmap->n_matches >= currmap->max_matches) {
 725                                         currmap->max_matches = currmap->max_matches * 2 + 1;
 726                                         currmap->match = xrealloc(currmap->match,
 727                                                 sizeof(*currmap->match) * currmap->max_matches);
 728                                 }
 729                                 currmap->match[currmap->n_matches++] = xstrdup(first_word);
 730                         }
 731                         /*currmap->max_mappings = 0; - done by xzalloc */
 732                         /*currmap->n_mappings = 0;*/
 733                         /*currmap->mapping = NULL;*/
 734                         /*currmap->script = NULL;*/
 735                         {
 736                                 struct mapping_defn_t **where = &defn->mappings;
 737                                 while (*where != NULL) {
 738                                         where = &(*where)->next;
 739                                 }
 740                                 *where = currmap;
 741                                 /*currmap->next = NULL;*/
 742                         }
 743                         debug_noise("Added mapping\n");
 744 #endif
 745                         currently_processing = MAPPING;
 746                 } else if (strcmp(first_word, "iface") == 0) {
 747                         static const struct address_family_t *const addr_fams[] = {
 748 #if ENABLE_FEATURE_IFUPDOWN_IPV4
 749                                 &addr_inet,
 750 #endif
 751 #if ENABLE_FEATURE_IFUPDOWN_IPV6
 752                                 &addr_inet6,
 753 #endif
 754                                 NULL
 755                         };
 756                         char *iface_name;
 757                         char *address_family_name;
 758                         char *method_name;
 759                         llist_t *iface_list;
 760
 761                         currif = xzalloc(sizeof(*currif));
 762                         iface_name = next_word(&rest_of_line);
 763                         address_family_name = next_word(&rest_of_line);
 764                         method_name = next_word(&rest_of_line);
 765
 766                         if (method_name == NULL)
 767                                 bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
 768
 769                         /* ship any trailing whitespace */
 770                         rest_of_line = skip_whitespace(rest_of_line);
 771
 772                         if (rest_of_line[0] != '\0' /* && rest_of_line[0] != '#' */)
 773                                 bb_error_msg_and_die("too many parameters \"%s\"", buf);
 774
 775                         currif->iface = xstrdup(iface_name);
 776
 777                         currif->address_family = get_address_family(addr_fams, address_family_name);
 778                         if (!currif->address_family)
 779                                 bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
 780
 781                         currif->method = get_method(currif->address_family, method_name);
 782                         if (!currif->method)
 783                                 bb_error_msg_and_die("unknown method \"%s\"", method_name);
 784
 785                         for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
 786                                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
 787                                 if ((strcmp(tmp->iface, currif->iface) == 0)
 788                                  && (tmp->address_family == currif->address_family)
 789                                 ) {
 790                                         bb_error_msg_and_die("duplicate interface \"%s\"", tmp->iface);
 791                                 }
 792                         }
 793                         llist_add_to_end(&(defn->ifaces), (char*)currif);
 794
 795                         debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
 796                         currently_processing = IFACE;
 797                 } else if (strcmp(first_word, "auto") == 0) {
 798                         while ((first_word = next_word(&rest_of_line)) != NULL) {
 799
 800                                 /* Check the interface isnt already listed */
 801                                 if (find_list_string(defn->autointerfaces, first_word)) {
 802                                         bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
 803                                 }
 804
 805                                 /* Add the interface to the list */
 806                                 llist_add_to_end(&(defn->autointerfaces), xstrdup(first_word));
 807                                 debug_noise("\nauto %s\n", first_word);
 808                         }
 809                         currently_processing = NONE;
 810                 } else {
 811                         switch (currently_processing) {
 812                         case IFACE:
 813                                 if (rest_of_line[0] == '\0')
 814                                         bb_error_msg_and_die("option with empty value \"%s\"", buf);
 815
 816                                 if (strcmp(first_word, "up") != 0
 817                                  && strcmp(first_word, "down") != 0
 818                                  && strcmp(first_word, "pre-up") != 0
 819                                  && strcmp(first_word, "post-down") != 0
 820                                 ) {
 821                                         int i;
 822                                         for (i = 0; i < currif->n_options; i++) {
 823                                                 if (strcmp(currif->option[i].name, first_word) == 0)
 824                                                         bb_error_msg_and_die("duplicate option \"%s\"", buf);
 825                                         }
 826                                 }
 827                                 if (currif->n_options >= currif->max_options) {
 828                                         currif->max_options += 10;
 829                                         currif->option = xrealloc(currif->option,
 830                                                 sizeof(*currif->option) * currif->max_options);
 831                                 }
 832                                 debug_noise("\t%s=%s\n", first_word, rest_of_line);
 833                                 currif->option[currif->n_options].name = xstrdup(first_word);
 834                                 currif->option[currif->n_options].value = xstrdup(rest_of_line);
 835                                 currif->n_options++;
 836                                 break;
 837                         case MAPPING:
 838 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 839                                 if (strcmp(first_word, "script") == 0) {
 840                                         if (currmap->script != NULL)
 841                                                 bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
 842                                         currmap->script = xstrdup(next_word(&rest_of_line));
 843                                 } else if (strcmp(first_word, "map") == 0) {
 844                                         if (currmap->n_mappings >= currmap->max_mappings) {
 845                                                 currmap->max_mappings = currmap->max_mappings * 2 + 1;
 846                                                 currmap->mapping = xrealloc(currmap->mapping,
 847                                                         sizeof(char *) * currmap->max_mappings);
 848                                         }
 849                                         currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&rest_of_line));
 850                                         currmap->n_mappings++;
 851                                 } else {
 852                                         bb_error_msg_and_die("misplaced option \"%s\"", buf);
 853                                 }
 854 #endif
 855                                 break;
 856                         case NONE:
 857                         default:
 858                                 bb_error_msg_and_die("misplaced option \"%s\"", buf);
 859                         }
 860                 }
 861                 free(buf);
 862         } /* while (fgets) */
 863
 864         if (ferror(f) != 0) {
 865                 /* ferror does NOT set errno! */
 866                 bb_error_msg_and_die("%s: I/O error", filename);
 867         }
 868         fclose(f);
 869
 870         return defn;
 871 }
 872
 873 static char *setlocalenv(const char *format, const char *name, const char *value)
 874 {
 875         char *result;
 876         char *here;
 877         char *there;
 878
 879         result = xasprintf(format, name, value);
 880
 881         for (here = there = result; *there != '=' && *there; there++) {
 882                 if (*there == '-')
 883                         *there = '_';
 884                 if (isalpha(*there))
 885                         *there = toupper(*there);
 886
 887                 if (isalnum(*there) || *there == '_') {
 888                         *here = *there;
 889                         here++;
 890                 }
 891         }
 892         memmove(here, there, strlen(there) + 1);
 893
 894         return result;
 895 }
 896
 897 static void set_environ(struct interface_defn_t *iface, const char *mode)
 898 {
 899         char **environend;
 900         int i;
 901         const int n_env_entries = iface->n_options + 5;
 902         char **ppch;
 903
 904         if (my_environ != NULL) {
 905                 for (ppch = my_environ; *ppch; ppch++) {
 906                         free(*ppch);
 907                         *ppch = NULL;
 908                 }
 909                 free(my_environ);
 910         }
 911         my_environ = xzalloc(sizeof(char *) * (n_env_entries + 1 /* for final NULL */ ));
 912         environend = my_environ;
 913
 914         for (i = 0; i < iface->n_options; i++) {
 915                 if (strcmp(iface->option[i].name, "up") == 0
 916                  || strcmp(iface->option[i].name, "down") == 0
 917                  || strcmp(iface->option[i].name, "pre-up") == 0
 918                  || strcmp(iface->option[i].name, "post-down") == 0
 919                 ) {
 920                         continue;
 921                 }
 922                 *(environend++) = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
 923         }
 924
 925         *(environend++) = setlocalenv("%s=%s", "IFACE", iface->iface);
 926         *(environend++) = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
 927         *(environend++) = setlocalenv("%s=%s", "METHOD", iface->method->name);
 928         *(environend++) = setlocalenv("%s=%s", "MODE", mode);
 929         *(environend++) = setlocalenv("%s=%s", "PATH", startup_PATH);
 930 }
 931
 932 static int doit(char *str)
 933 {
 934         if (option_mask32 & (OPT_no_act|OPT_verbose)) {
 935                 puts(str);
 936         }
 937         if (!(option_mask32 & OPT_no_act)) {
 938                 pid_t child;
 939                 int status;
 940
 941                 fflush(NULL);
 942                 child = vfork();
 943                 switch (child) {
 944                 case -1: /* failure */
 945                         return 0;
 946                 case 0: /* child */
 947                         execle(DEFAULT_SHELL, DEFAULT_SHELL, "-c", str, NULL, my_environ);
 948                         _exit(127);
 949                 }
 950                 safe_waitpid(child, &status, 0);
 951                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 952                         return 0;
 953                 }
 954         }
 955         return 1;
 956 }
 957
 958 static int execute_all(struct interface_defn_t *ifd, const char *opt)
 959 {
 960         int i;
 961         char *buf;
 962         for (i = 0; i < ifd->n_options; i++) {
 963                 if (strcmp(ifd->option[i].name, opt) == 0) {
 964                         if (!doit(ifd->option[i].value)) {
 965                                 return 0;
 966                         }
 967                 }
 968         }
 969
 970         buf = xasprintf("run-parts /etc/network/if-%s.d", opt);
 971         /* heh, we don't bother free'ing it */
 972         return doit(buf);
 973 }
 974
 975 static int check(char *str)
 976 {
 977         return str != NULL;
 978 }
 979
 980 static int iface_up(struct interface_defn_t *iface)
 981 {
 982         if (!iface->method->up(iface, check)) return -1;
 983         set_environ(iface, "start");
 984         if (!execute_all(iface, "pre-up")) return 0;
 985         if (!iface->method->up(iface, doit)) return 0;
 986         if (!execute_all(iface, "up")) return 0;
 987         return 1;
 988 }
 989
 990 static int iface_down(struct interface_defn_t *iface)
 991 {
 992         if (!iface->method->down(iface,check)) return -1;
 993         set_environ(iface, "stop");
 994         if (!execute_all(iface, "down")) return 0;
 995         if (!iface->method->down(iface, doit)) return 0;
 996         if (!execute_all(iface, "post-down")) return 0;
 997         return 1;
 998 }
 999
1000 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1001 static int popen2(FILE **in, FILE **out, char *command, char *param)
1002 {
1003         char *argv[3] = { command, param, NULL };
1004         struct fd_pair infd, outfd;
1005         pid_t pid;
1006
1007         xpiped_pair(infd);
1008         xpiped_pair(outfd);
1009
1010         fflush(NULL);
1011         pid = vfork();
1012
1013         switch (pid) {
1014         case -1:  /* failure */
1015                 bb_perror_msg_and_die("vfork");
1016         case 0:  /* child */
1017                 /* NB: close _first_, then move fds! */
1018                 close(infd.wr);
1019                 close(outfd.rd);
1020                 xmove_fd(infd.rd, 0);
1021                 xmove_fd(outfd.wr, 1);
1022                 BB_EXECVP(command, argv);
1023                 _exit(127);
1024         }
1025         /* parent */
1026         close(infd.rd);
1027         close(outfd.wr);
1028         *in = fdopen(infd.wr, "w");
1029         *out = fdopen(outfd.rd, "r");
1030         return pid;
1031 }
1032
1033 static char *run_mapping(char *physical, struct mapping_defn_t *map)
1034 {
1035         FILE *in, *out;
1036         int i, status;
1037         pid_t pid;
1038
1039         char *logical = xstrdup(physical);
1040
1041         /* Run the mapping script. Never fails. */
1042         pid = popen2(&in, &out, map->script, physical);
1043
1044         /* Write mappings to stdin of mapping script. */
1045         for (i = 0; i < map->n_mappings; i++) {
1046                 fprintf(in, "%s\n", map->mapping[i]);
1047         }
1048         fclose(in);
1049         safe_waitpid(pid, &status, 0);
1050
1051         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
1052                 /* If the mapping script exited successfully, try to
1053                  * grab a line of output and use that as the name of the
1054                  * logical interface. */
1055                 char *new_logical = xmalloc_getline(out);
1056
1057                 if (new_logical) {
1058                         /* If we are able to read a line of output from the script,
1059                          * remove any trailing whitespace and use this value
1060                          * as the name of the logical interface. */
1061                         char *pch = new_logical + strlen(new_logical) - 1;
1062
1063                         while (pch >= new_logical && isspace(*pch))
1064                                 *(pch--) = '\0';
1065
1066                         free(logical);
1067                         logical = new_logical;
1068                 }
1069         }
1070
1071         fclose(out);
1072
1073         return logical;
1074 }
1075 #endif /* FEATURE_IFUPDOWN_MAPPING */
1076
1077 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
1078 {
1079         unsigned iface_len = strlen(iface);
1080         llist_t *search = state_list;
1081
1082         while (search) {
1083                 if ((strncmp(search->data, iface, iface_len) == 0)
1084                  && (search->data[iface_len] == '=')
1085                 ) {
1086                         return search;
1087                 }
1088                 search = search->link;
1089         }
1090         return NULL;
1091 }
1092
1093 /* read the previous state from the state file */
1094 static llist_t *read_iface_state(void)
1095 {
1096         llist_t *state_list = NULL;
1097         FILE *state_fp = fopen(CONFIG_IFUPDOWN_IFSTATE_PATH, "r");
1098
1099         if (state_fp) {
1100                 char *start, *end_ptr;
1101                 while ((start = xmalloc_fgets(state_fp)) != NULL) {
1102                         /* We should only need to check for a single character */
1103                         end_ptr = start + strcspn(start, " \t\n");
1104                         *end_ptr = '\0';
1105                         llist_add_to(&state_list, start);
1106                 }
1107                 fclose(state_fp);
1108         }
1109         return state_list;
1110 }
1111
1112
1113 int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1114 int ifupdown_main(int argc, char **argv)
1115 {
1116         int (*cmds)(struct interface_defn_t *);
1117         struct interfaces_file_t *defn;
1118         llist_t *target_list = NULL;
1119         const char *interfaces = "/etc/network/interfaces";
1120         bool any_failures = 0;
1121
1122         cmds = iface_down;
1123         if (applet_name[2] == 'u') {
1124                 /* ifup command */
1125                 cmds = iface_up;
1126         }
1127
1128         getopt32(argv, OPTION_STR, &interfaces);
1129         if (argc - optind > 0) {
1130                 if (DO_ALL) bb_show_usage();
1131         } else {
1132                 if (!DO_ALL) bb_show_usage();
1133         }
1134
1135         debug_noise("reading %s file:\n", interfaces);
1136         defn = read_interfaces(interfaces);
1137         debug_noise("\ndone reading %s\n\n", interfaces);
1138
1139         startup_PATH = getenv("PATH");
1140         if (!startup_PATH) startup_PATH = "";
1141
1142         /* Create a list of interfaces to work on */
1143         if (DO_ALL) {
1144                 target_list = defn->autointerfaces;
1145         } else {
1146                 llist_add_to_end(&target_list, argv[optind]);
1147         }
1148
1149         /* Update the interfaces */
1150         while (target_list) {
1151                 llist_t *iface_list;
1152                 struct interface_defn_t *currif;
1153                 char *iface;
1154                 char *liface;
1155                 char *pch;
1156                 bool okay = 0;
1157                 unsigned cmds_ret;
1158
1159                 iface = xstrdup(target_list->data);
1160                 target_list = target_list->link;
1161
1162                 pch = strchr(iface, '=');
1163                 if (pch) {
1164                         *pch = '\0';
1165                         liface = xstrdup(pch + 1);
1166                 } else {
1167                         liface = xstrdup(iface);
1168                 }
1169
1170                 if (!FORCE) {
1171                         llist_t *state_list = read_iface_state();
1172                         const llist_t *iface_state = find_iface_state(state_list, iface);
1173
1174                         if (cmds == iface_up) {
1175                                 /* ifup */
1176                                 if (iface_state) {
1177                                         bb_error_msg("interface %s already configured", iface);
1178                                         continue;
1179                                 }
1180                         } else {
1181                                 /* ifdown */
1182                                 if (!iface_state) {
1183                                         bb_error_msg("interface %s not configured", iface);
1184                                         continue;
1185                                 }
1186                         }
1187                         llist_free(state_list, free);
1188                 }
1189
1190 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1191                 if ((cmds == iface_up) && !NO_MAPPINGS) {
1192                         struct mapping_defn_t *currmap;
1193
1194                         for (currmap = defn->mappings; currmap; currmap = currmap->next) {
1195                                 int i;
1196                                 for (i = 0; i < currmap->n_matches; i++) {
1197                                         if (fnmatch(currmap->match[i], liface, 0) != 0)
1198                                                 continue;
1199                                         if (VERBOSE) {
1200                                                 printf("Running mapping script %s on %s\n", currmap->script, liface);
1201                                         }
1202                                         liface = run_mapping(iface, currmap);
1203                                         break;
1204                                 }
1205                         }
1206                 }
1207 #endif
1208
1209                 iface_list = defn->ifaces;
1210                 while (iface_list) {
1211                         currif = (struct interface_defn_t *) iface_list->data;
1212                         if (strcmp(liface, currif->iface) == 0) {
1213                                 char *oldiface = currif->iface;
1214
1215                                 okay = 1;
1216                                 currif->iface = iface;
1217
1218                                 debug_noise("\nConfiguring interface %s (%s)\n", liface, currif->address_family->name);
1219
1220                                 /* Call the cmds function pointer, does either iface_up() or iface_down() */
1221                                 cmds_ret = cmds(currif);
1222                                 if (cmds_ret == -1) {
1223                                         bb_error_msg("don't seem to have all the variables for %s/%s",
1224                                                         liface, currif->address_family->name);
1225                                         any_failures = 1;
1226                                 } else if (cmds_ret == 0) {
1227                                         any_failures = 1;
1228                                 }
1229
1230                                 currif->iface = oldiface;
1231                         }
1232                         iface_list = iface_list->link;
1233                 }
1234                 if (VERBOSE) {
1235                         bb_putchar('\n');
1236                 }
1237
1238                 if (!okay && !FORCE) {
1239                         bb_error_msg("ignoring unknown interface %s", liface);
1240                         any_failures = 1;
1241                 } else if (!NO_ACT) {
1242                         /* update the state file */
1243                         FILE *state_fp;
1244                         llist_t *state;
1245                         llist_t *state_list = read_iface_state();
1246                         llist_t *iface_state = find_iface_state(state_list, iface);
1247
1248                         if (cmds == iface_up) {
1249                                 char * const newiface = xasprintf("%s=%s", iface, liface);
1250                                 if (iface_state == NULL) {
1251                                         llist_add_to_end(&state_list, newiface);
1252                                 } else {
1253                                         free(iface_state->data);
1254                                         iface_state->data = newiface;
1255                                 }
1256                         } else {
1257                                 /* Remove an interface from state_list */
1258                                 llist_unlink(&state_list, iface_state);
1259                                 free(llist_pop(&iface_state));
1260                         }
1261
1262                         /* Actually write the new state */
1263                         state_fp = xfopen(CONFIG_IFUPDOWN_IFSTATE_PATH, "w");
1264                         state = state_list;
1265                         while (state) {
1266                                 if (state->data) {
1267                                         fprintf(state_fp, "%s\n", state->data);
1268                                 }
1269                                 state = state->link;
1270                         }
1271                         fclose(state_fp);
1272                         llist_free(state_list, free);
1273                 }
1274         }
1275
1276         return any_failures;
1277 }