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 GPLv2 or later, see file LICENSE in this source tree.
  18  */
  19
  20 #include "libbb.h"
  21 /* After libbb.h, since it needs sys/types.h on some systems */
  22 #include <sys/utsname.h>
  23 #include <fnmatch.h>
  24
  25 #define MAX_OPT_DEPTH 10
  26 #define EUNBALBRACK 10001
  27 #define EUNDEFVAR   10002
  28 #define EUNBALPER   10000
  29
  30 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
  31 #define MAX_INTERFACE_LENGTH 10
  32 #endif
  33
  34 #define UDHCPC_CMD_OPTIONS CONFIG_IFUPDOWN_UDHCPC_CMD_OPTIONS
  35
  36 #define debug_noise(args...) /*fprintf(stderr, args)*/
  37
  38 /* Forward declaration */
  39 struct interface_defn_t;
  40
  41 typedef int execfn(char *command);
  42
  43 struct method_t {
  44         const char *name;
  45         int (*up)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
  46         int (*down)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
  47 };
  48
  49 struct address_family_t {
  50         const char *name;
  51         int n_methods;
  52         const struct method_t *method;
  53 };
  54
  55 struct mapping_defn_t {
  56         struct mapping_defn_t *next;
  57
  58         int max_matches;
  59         int n_matches;
  60         char **match;
  61
  62         char *script;
  63
  64         int max_mappings;
  65         int n_mappings;
  66         char **mapping;
  67 };
  68
  69 struct variable_t {
  70         char *name;
  71         char *value;
  72 };
  73
  74 struct interface_defn_t {
  75         const struct address_family_t *address_family;
  76         const struct method_t *method;
  77
  78         char *iface;
  79         int max_options;
  80         int n_options;
  81         struct variable_t *option;
  82 };
  83
  84 struct interfaces_file_t {
  85         llist_t *autointerfaces;
  86         llist_t *ifaces;
  87         struct mapping_defn_t *mappings;
  88 };
  89
  90
  91 #define OPTION_STR "anvf" IF_FEATURE_IFUPDOWN_MAPPING("m") "i:"
  92 enum {
  93         OPT_do_all      = 0x1,
  94         OPT_no_act      = 0x2,
  95         OPT_verbose     = 0x4,
  96         OPT_force       = 0x8,
  97         OPT_no_mappings = 0x10,
  98 };
  99 #define DO_ALL      (option_mask32 & OPT_do_all)
 100 #define NO_ACT      (option_mask32 & OPT_no_act)
 101 #define VERBOSE     (option_mask32 & OPT_verbose)
 102 #define FORCE       (option_mask32 & OPT_force)
 103 #define NO_MAPPINGS (option_mask32 & OPT_no_mappings)
 104
 105
 106 struct globals {
 107         char **my_environ;
 108         const char *startup_PATH;
 109         char *shell;
 110 } FIX_ALIASING;
 111 #define G (*(struct globals*)&bb_common_bufsiz1)
 112 #define INIT_G() do { } while (0)
 113
 114
 115 #if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
 116
 117 static void addstr(char **bufp, const char *str, size_t str_length)
 118 {
 119         /* xasprintf trick will be smaller, but we are often
 120          * called with str_length == 1 - don't want to have
 121          * THAT much of malloc/freeing! */
 122         char *buf = *bufp;
 123         int len = (buf ? strlen(buf) : 0);
 124         str_length++;
 125         buf = xrealloc(buf, len + str_length);
 126         /* copies at most str_length-1 chars! */
 127         safe_strncpy(buf + len, str, str_length);
 128         *bufp = buf;
 129 }
 130
 131 static int strncmpz(const char *l, const char *r, size_t llen)
 132 {
 133         int i = strncmp(l, r, llen);
 134
 135         if (i == 0)
 136                 return - (unsigned char)r[llen];
 137         return i;
 138 }
 139
 140 static char *get_var(const char *id, size_t idlen, struct interface_defn_t *ifd)
 141 {
 142         int i;
 143
 144         if (strncmpz(id, "iface", idlen) == 0) {
 145                 // ubuntu's ifup doesn't do this:
 146                 //static char *label_buf;
 147                 //char *result;
 148                 //free(label_buf);
 149                 //label_buf = xstrdup(ifd->iface);
 150                 // Remove virtual iface suffix
 151                 //result = strchrnul(label_buf, ':');
 152                 //*result = '\0';
 153                 //return label_buf;
 154
 155                 return ifd->iface;
 156         }
 157         if (strncmpz(id, "label", idlen) == 0) {
 158                 return ifd->iface;
 159         }
 160         for (i = 0; i < ifd->n_options; i++) {
 161                 if (strncmpz(id, ifd->option[i].name, idlen) == 0) {
 162                         return ifd->option[i].value;
 163                 }
 164         }
 165         return NULL;
 166 }
 167
 168 # if ENABLE_FEATURE_IFUPDOWN_IP
 169 static int count_netmask_bits(const char *dotted_quad)
 170 {
 171 //      int result;
 172 //      unsigned a, b, c, d;
 173 //      /* Found a netmask...  Check if it is dotted quad */
 174 //      if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
 175 //              return -1;
 176 //      if ((a|b|c|d) >> 8)
 177 //              return -1; /* one of numbers is >= 256 */
 178 //      d |= (a << 24) | (b << 16) | (c << 8); /* IP */
 179 //      d = ~d; /* 11110000 -> 00001111 */
 180
 181         /* Shorter version */
 182         int result;
 183         struct in_addr ip;
 184         unsigned d;
 185
 186         if (inet_aton(dotted_quad, &ip) == 0)
 187                 return -1; /* malformed dotted IP */
 188         d = ntohl(ip.s_addr); /* IP in host order */
 189         d = ~d; /* 11110000 -> 00001111 */
 190         if (d & (d+1)) /* check that it is in 00001111 form */
 191                 return -1; /* no it is not */
 192         result = 32;
 193         while (d) {
 194                 d >>= 1;
 195                 result--;
 196         }
 197         return result;
 198 }
 199 # endif
 200
 201 static char *parse(const char *command, struct interface_defn_t *ifd)
 202 {
 203         size_t old_pos[MAX_OPT_DEPTH] = { 0 };
 204         int okay[MAX_OPT_DEPTH] = { 1 };
 205         int opt_depth = 1;
 206         char *result = NULL;
 207
 208         while (*command) {
 209                 switch (*command) {
 210                 default:
 211                         addstr(&result, command, 1);
 212                         command++;
 213                         break;
 214                 case '\\':
 215                         if (command[1]) {
 216                                 addstr(&result, command + 1, 1);
 217                                 command += 2;
 218                         } else {
 219                                 addstr(&result, command, 1);
 220                                 command++;
 221                         }
 222                         break;
 223                 case '[':
 224                         if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
 225                                 old_pos[opt_depth] = result ? strlen(result) : 0;
 226                                 okay[opt_depth] = 1;
 227                                 opt_depth++;
 228                                 command += 2;
 229                         } else {
 230                                 addstr(&result, "[", 1);
 231                                 command++;
 232                         }
 233                         break;
 234                 case ']':
 235                         if (command[1] == ']' && opt_depth > 1) {
 236                                 opt_depth--;
 237                                 if (!okay[opt_depth]) {
 238                                         result[old_pos[opt_depth]] = '\0';
 239                                 }
 240                                 command += 2;
 241                         } else {
 242                                 addstr(&result, "]", 1);
 243                                 command++;
 244                         }
 245                         break;
 246                 case '%':
 247                         {
 248                                 char *nextpercent;
 249                                 char *varvalue;
 250
 251                                 command++;
 252                                 nextpercent = strchr(command, '%');
 253                                 if (!nextpercent) {
 254                                         errno = EUNBALPER;
 255                                         free(result);
 256                                         return NULL;
 257                                 }
 258
 259                                 varvalue = get_var(command, nextpercent - command, ifd);
 260
 261                                 if (varvalue) {
 262 # if ENABLE_FEATURE_IFUPDOWN_IP
 263                                         /* "hwaddress <class> <address>":
 264                                          * unlike ifconfig, ip doesnt want <class>
 265                                          * (usually "ether" keyword). Skip it. */
 266                                         if (strncmp(command, "hwaddress", 9) == 0) {
 267                                                 varvalue = skip_whitespace(skip_non_whitespace(varvalue));
 268                                         }
 269 # endif
 270                                         addstr(&result, varvalue, strlen(varvalue));
 271                                 } else {
 272 # if ENABLE_FEATURE_IFUPDOWN_IP
 273                                         /* Sigh...  Add a special case for 'ip' to convert from
 274                                          * dotted quad to bit count style netmasks.  */
 275                                         if (strncmp(command, "bnmask", 6) == 0) {
 276                                                 unsigned res;
 277                                                 varvalue = get_var("netmask", 7, ifd);
 278                                                 if (varvalue) {
 279                                                         res = count_netmask_bits(varvalue);
 280                                                         if (res > 0) {
 281                                                                 const char *argument = utoa(res);
 282                                                                 addstr(&result, argument, strlen(argument));
 283                                                                 command = nextpercent + 1;
 284                                                                 break;
 285                                                         }
 286                                                 }
 287                                         }
 288 # endif
 289                                         okay[opt_depth - 1] = 0;
 290                                 }
 291
 292                                 command = nextpercent + 1;
 293                         }
 294                         break;
 295                 }
 296         }
 297
 298         if (opt_depth > 1) {
 299                 errno = EUNBALBRACK;
 300                 free(result);
 301                 return NULL;
 302         }
 303
 304         if (!okay[0]) {
 305                 errno = EUNDEFVAR;
 306                 free(result);
 307                 return NULL;
 308         }
 309
 310         return result;
 311 }
 312
 313 /* execute() returns 1 for success and 0 for failure */
 314 static int execute(const char *command, struct interface_defn_t *ifd, execfn *exec)
 315 {
 316         char *out;
 317         int ret;
 318
 319         out = parse(command, ifd);
 320         if (!out) {
 321                 /* parse error? */
 322                 return 0;
 323         }
 324         /* out == "": parsed ok but not all needed variables known, skip */
 325         ret = out[0] ? (*exec)(out) : 1;
 326
 327         free(out);
 328         if (ret != 1) {
 329                 return 0;
 330         }
 331         return 1;
 332 }
 333
 334 #endif /* FEATURE_IFUPDOWN_IPV4 || FEATURE_IFUPDOWN_IPV6 */
 335
 336
 337 #if ENABLE_FEATURE_IFUPDOWN_IPV6
 338
 339 static int FAST_FUNC loopback_up6(struct interface_defn_t *ifd, execfn *exec)
 340 {
 341 # if ENABLE_FEATURE_IFUPDOWN_IP
 342         int result;
 343         result = execute("ip addr add ::1 dev %iface%", ifd, exec);
 344         result += execute("ip link set %iface% up", ifd, exec);
 345         return ((result == 2) ? 2 : 0);
 346 # else
 347         return execute("ifconfig %iface% add ::1", ifd, exec);
 348 # endif
 349 }
 350
 351 static int FAST_FUNC loopback_down6(struct interface_defn_t *ifd, execfn *exec)
 352 {
 353 # if ENABLE_FEATURE_IFUPDOWN_IP
 354         return execute("ip link set %iface% down", ifd, exec);
 355 # else
 356         return execute("ifconfig %iface% del ::1", ifd, exec);
 357 # endif
 358 }
 359
 360 static int FAST_FUNC manual_up_down6(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 361 {
 362         return 1;
 363 }
 364
 365 static int FAST_FUNC static_up6(struct interface_defn_t *ifd, execfn *exec)
 366 {
 367         int result;
 368 # if ENABLE_FEATURE_IFUPDOWN_IP
 369         result = execute("ip addr add %address%/%netmask% dev %iface%[[ label %label%]]", ifd, exec);
 370         result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
 371         /* Was: "[[ ip ....%gateway% ]]". Removed extra spaces w/o checking */
 372         result += execute("[[ip route add ::/0 via %gateway%]]", ifd, exec);
 373 # else
 374         result = execute("ifconfig %iface%[[ media %media%]][[ hw %hwaddress%]][[ mtu %mtu%]] up", ifd, exec);
 375         result += execute("ifconfig %iface% add %address%/%netmask%", ifd, exec);
 376         result += execute("[[route -A inet6 add ::/0 gw %gateway%]]", ifd, exec);
 377 # endif
 378         return ((result == 3) ? 3 : 0);
 379 }
 380
 381 static int FAST_FUNC static_down6(struct interface_defn_t *ifd, execfn *exec)
 382 {
 383 # if ENABLE_FEATURE_IFUPDOWN_IP
 384         return execute("ip link set %iface% down", ifd, exec);
 385 # else
 386         return execute("ifconfig %iface% down", ifd, exec);
 387 # endif
 388 }
 389
 390 # if ENABLE_FEATURE_IFUPDOWN_IP
 391 static int FAST_FUNC v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
 392 {
 393         int result;
 394         result = execute("ip tunnel add %iface% mode sit remote "
 395                         "%endpoint%[[ local %local%]][[ ttl %ttl%]]", ifd, exec);
 396         result += execute("ip link set %iface% up", ifd, exec);
 397         result += execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec);
 398         result += execute("[[ip route add ::/0 via %gateway%]]", ifd, exec);
 399         return ((result == 4) ? 4 : 0);
 400 }
 401
 402 static int FAST_FUNC v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
 403 {
 404         return execute("ip tunnel del %iface%", ifd, exec);
 405 }
 406 # endif
 407
 408 static const struct method_t methods6[] = {
 409 # if ENABLE_FEATURE_IFUPDOWN_IP
 410         { "v4tunnel" , v4tunnel_up     , v4tunnel_down   , },
 411 # endif
 412         { "static"   , static_up6      , static_down6    , },
 413         { "manual"   , manual_up_down6 , manual_up_down6 , },
 414         { "loopback" , loopback_up6    , loopback_down6  , },
 415 };
 416
 417 static const struct address_family_t addr_inet6 = {
 418         "inet6",
 419         ARRAY_SIZE(methods6),
 420         methods6
 421 };
 422
 423 #endif /* FEATURE_IFUPDOWN_IPV6 */
 424
 425
 426 #if ENABLE_FEATURE_IFUPDOWN_IPV4
 427
 428 static int FAST_FUNC loopback_up(struct interface_defn_t *ifd, execfn *exec)
 429 {
 430 # if ENABLE_FEATURE_IFUPDOWN_IP
 431         int result;
 432         result = execute("ip addr add 127.0.0.1/8 dev %iface%", ifd, exec);
 433         result += execute("ip link set %iface% up", ifd, exec);
 434         return ((result == 2) ? 2 : 0);
 435 # else
 436         return execute("ifconfig %iface% 127.0.0.1 up", ifd, exec);
 437 # endif
 438 }
 439
 440 static int FAST_FUNC loopback_down(struct interface_defn_t *ifd, execfn *exec)
 441 {
 442 # if ENABLE_FEATURE_IFUPDOWN_IP
 443         int result;
 444         result = execute("ip addr flush dev %iface%", ifd, exec);
 445         result += execute("ip link set %iface% down", ifd, exec);
 446         return ((result == 2) ? 2 : 0);
 447 # else
 448         return execute("ifconfig %iface% 127.0.0.1 down", ifd, exec);
 449 # endif
 450 }
 451
 452 static int FAST_FUNC static_up(struct interface_defn_t *ifd, execfn *exec)
 453 {
 454         int result;
 455 # if ENABLE_FEATURE_IFUPDOWN_IP
 456         result = execute("ip addr add %address%/%bnmask%[[ broadcast %broadcast%]] "
 457                         "dev %iface%[[ peer %pointopoint%]][[ label %label%]]", ifd, exec);
 458         result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
 459         result += execute("[[ip route add default via %gateway% dev %iface%]]", ifd, exec);
 460         return ((result == 3) ? 3 : 0);
 461 # else
 462         /* ifconfig said to set iface up before it processes hw %hwaddress%,
 463          * which then of course fails. Thus we run two separate ifconfig */
 464         result = execute("ifconfig %iface%[[ hw %hwaddress%]][[ media %media%]][[ mtu %mtu%]] up",
 465                                 ifd, exec);
 466         result += execute("ifconfig %iface% %address% netmask %netmask%"
 467                                 "[[ broadcast %broadcast%]][[ pointopoint %pointopoint%]] ",
 468                                 ifd, exec);
 469         result += execute("[[route add default gw %gateway% %iface%]]", ifd, exec);
 470         return ((result == 3) ? 3 : 0);
 471 # endif
 472 }
 473
 474 static int FAST_FUNC static_down(struct interface_defn_t *ifd, execfn *exec)
 475 {
 476         int result;
 477 # if ENABLE_FEATURE_IFUPDOWN_IP
 478         result = execute("ip addr flush dev %iface%", ifd, exec);
 479         result += execute("ip link set %iface% down", ifd, exec);
 480 # else
 481         /* result = execute("[[route del default gw %gateway% %iface%]]", ifd, exec); */
 482         /* Bringing the interface down deletes the routes in itself.
 483            Otherwise this fails if we reference 'gateway' when using this from dhcp_down */
 484         result = 1;
 485         result += execute("ifconfig %iface% down", ifd, exec);
 486 # endif
 487         return ((result == 2) ? 2 : 0);
 488 }
 489
 490 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 491 struct dhcp_client_t {
 492         const char *name;
 493         const char *startcmd;
 494         const char *stopcmd;
 495 };
 496
 497 static const struct dhcp_client_t ext_dhcp_clients[] = {
 498         { "dhcpcd",
 499                 "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %client%]][[ -l %leasetime%]] %iface%",
 500                 "dhcpcd -k %iface%",
 501         },
 502         { "dhclient",
 503                 "dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
 504                 "kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
 505         },
 506         { "pump",
 507                 "pump -i %iface%[[ -h %hostname%]][[ -l %leasehours%]]",
 508                 "pump -i %iface% -k",
 509         },
 510         { "udhcpc",
 511                 "udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %client%]]"
 512                                 "[[ -s %script%]][[ %udhcpc_opts%]]",
 513                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
 514         },
 515 };
 516 # endif /* FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
 517
 518 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 519 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 520 {
 521         unsigned i;
 522 #  if ENABLE_FEATURE_IFUPDOWN_IP
 523         /* ip doesn't up iface when it configures it (unlike ifconfig) */
 524         if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
 525                 return 0;
 526 #  else
 527         /* needed if we have hwaddress on dhcp iface */
 528         if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
 529                 return 0;
 530 #  endif
 531         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
 532                 if (exists_execable(ext_dhcp_clients[i].name))
 533                         return execute(ext_dhcp_clients[i].startcmd, ifd, exec);
 534         }
 535         bb_error_msg("no dhcp clients found");
 536         return 0;
 537 }
 538 # elif ENABLE_UDHCPC
 539 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 540 {
 541 #  if ENABLE_FEATURE_IFUPDOWN_IP
 542         /* ip doesn't up iface when it configures it (unlike ifconfig) */
 543         if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
 544                 return 0;
 545 #  else
 546         /* needed if we have hwaddress on dhcp iface */
 547         if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
 548                 return 0;
 549 #  endif
 550         return execute("udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid "
 551                         "-i %iface%[[ -H %hostname%]][[ -c %client%]][[ -s %script%]][[ %udhcpc_opts%]]",
 552                         ifd, exec);
 553 }
 554 # else
 555 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd UNUSED_PARAM,
 556                 execfn *exec UNUSED_PARAM)
 557 {
 558         return 0; /* no dhcp support */
 559 }
 560 # endif
 561
 562 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 563 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 564 {
 565         int result = 0;
 566         unsigned i;
 567
 568         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
 569                 if (exists_execable(ext_dhcp_clients[i].name)) {
 570                         result = execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
 571                         if (result)
 572                                 break;
 573                 }
 574         }
 575
 576         if (!result)
 577                 bb_error_msg("warning: no dhcp clients found and stopped");
 578
 579         /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
 580            and it may come back up because udhcpc is still shutting down */
 581         usleep(100000);
 582         result += static_down(ifd, exec);
 583         return ((result == 3) ? 3 : 0);
 584 }
 585 # elif ENABLE_UDHCPC
 586 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 587 {
 588         int result;
 589         result = execute(
 590                 "test -f /var/run/udhcpc.%iface%.pid && "
 591                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
 592                 ifd, exec);
 593         /* Also bring the hardware interface down since
 594            killing the dhcp client alone doesn't do it.
 595            This enables consecutive ifup->ifdown->ifup */
 596         /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
 597            and it may come back up because udhcpc is still shutting down */
 598         usleep(100000);
 599         result += static_down(ifd, exec);
 600         return ((result == 3) ? 3 : 0);
 601 }
 602 # else
 603 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd UNUSED_PARAM,
 604                 execfn *exec UNUSED_PARAM)
 605 {
 606         return 0; /* no dhcp support */
 607 }
 608 # endif
 609
 610 static int FAST_FUNC manual_up_down(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 611 {
 612         return 1;
 613 }
 614
 615 static int FAST_FUNC bootp_up(struct interface_defn_t *ifd, execfn *exec)
 616 {
 617         return execute("bootpc[[ --bootfile %bootfile%]] --dev %iface%"
 618                         "[[ --server %server%]][[ --hwaddr %hwaddr%]]"
 619                         " --returniffail --serverbcast", ifd, exec);
 620 }
 621
 622 static int FAST_FUNC ppp_up(struct interface_defn_t *ifd, execfn *exec)
 623 {
 624         return execute("pon[[ %provider%]]", ifd, exec);
 625 }
 626
 627 static int FAST_FUNC ppp_down(struct interface_defn_t *ifd, execfn *exec)
 628 {
 629         return execute("poff[[ %provider%]]", ifd, exec);
 630 }
 631
 632 static int FAST_FUNC wvdial_up(struct interface_defn_t *ifd, execfn *exec)
 633 {
 634         return execute("start-stop-daemon --start -x wvdial "
 635                 "-p /var/run/wvdial.%iface% -b -m --[[ %provider%]]", ifd, exec);
 636 }
 637
 638 static int FAST_FUNC wvdial_down(struct interface_defn_t *ifd, execfn *exec)
 639 {
 640         return execute("start-stop-daemon --stop -x wvdial "
 641                         "-p /var/run/wvdial.%iface% -s 2", ifd, exec);
 642 }
 643
 644 static const struct method_t methods[] = {
 645         { "manual"  , manual_up_down, manual_up_down, },
 646         { "wvdial"  , wvdial_up     , wvdial_down   , },
 647         { "ppp"     , ppp_up        , ppp_down      , },
 648         { "static"  , static_up     , static_down   , },
 649         { "bootp"   , bootp_up      , static_down   , },
 650         { "dhcp"    , dhcp_up       , dhcp_down     , },
 651         { "loopback", loopback_up   , loopback_down , },
 652 };
 653
 654 static const struct address_family_t addr_inet = {
 655         "inet",
 656         ARRAY_SIZE(methods),
 657         methods
 658 };
 659
 660 #endif  /* FEATURE_IFUPDOWN_IPV4 */
 661
 662
 663 /* Returns pointer to the next word, or NULL.
 664  * In 1st case, advances *buf to the word after this one.
 665  */
 666 static char *next_word(char **buf)
 667 {
 668         unsigned length;
 669         char *word;
 670
 671         /* Skip over leading whitespace */
 672         word = skip_whitespace(*buf);
 673
 674         /* Stop on EOL */
 675         if (*word == '\0')
 676                 return NULL;
 677
 678         /* Find the length of this word (can't be 0) */
 679         length = strcspn(word, " \t\n");
 680
 681         /* Unless we are already at NUL, store NUL and advance */
 682         if (word[length] != '\0')
 683                 word[length++] = '\0';
 684
 685         *buf = skip_whitespace(word + length);
 686
 687         return word;
 688 }
 689
 690 static const struct address_family_t *get_address_family(const struct address_family_t *const af[], char *name)
 691 {
 692         int i;
 693
 694         if (!name)
 695                 return NULL;
 696
 697         for (i = 0; af[i]; i++) {
 698                 if (strcmp(af[i]->name, name) == 0) {
 699                         return af[i];
 700                 }
 701         }
 702         return NULL;
 703 }
 704
 705 static const struct method_t *get_method(const struct address_family_t *af, char *name)
 706 {
 707         int i;
 708
 709         if (!name)
 710                 return NULL;
 711         /* TODO: use index_in_str_array() */
 712         for (i = 0; i < af->n_methods; i++) {
 713                 if (strcmp(af->method[i].name, name) == 0) {
 714                         return &af->method[i];
 715                 }
 716         }
 717         return NULL;
 718 }
 719
 720 static struct interfaces_file_t *read_interfaces(const char *filename)
 721 {
 722         /* Let's try to be compatible.
 723          *
 724          * "man 5 interfaces" says:
 725          * Lines starting with "#" are ignored. Note that end-of-line
 726          * comments are NOT supported, comments must be on a line of their own.
 727          * A line may be extended across multiple lines by making
 728          * the last character a backslash.
 729          *
 730          * Seen elsewhere in example config file:
 731          * A first non-blank "#" character makes the rest of the line
 732          * be ignored. Blank lines are ignored. Lines may be indented freely.
 733          * A "\" character at the very end of the line indicates the next line
 734          * should be treated as a continuation of the current one.
 735          */
 736 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 737         struct mapping_defn_t *currmap = NULL;
 738 #endif
 739         struct interface_defn_t *currif = NULL;
 740         struct interfaces_file_t *defn;
 741         FILE *f;
 742         char *buf;
 743         char *first_word;
 744         char *rest_of_line;
 745         enum { NONE, IFACE, MAPPING } currently_processing = NONE;
 746
 747         defn = xzalloc(sizeof(*defn));
 748         f = xfopen_for_read(filename);
 749
 750         while ((buf = xmalloc_fgetline(f)) != NULL) {
 751 #if ENABLE_DESKTOP
 752                 /* Trailing "\" concatenates lines */
 753                 char *p;
 754                 while ((p = last_char_is(buf, '\\')) != NULL) {
 755                         *p = '\0';
 756                         rest_of_line = xmalloc_fgetline(f);
 757                         if (!rest_of_line)
 758                                 break;
 759                         p = xasprintf("%s%s", buf, rest_of_line);
 760                         free(buf);
 761                         free(rest_of_line);
 762                         buf = p;
 763                 }
 764 #endif
 765                 rest_of_line = buf;
 766                 first_word = next_word(&rest_of_line);
 767                 if (!first_word || *first_word == '#') {
 768                         free(buf);
 769                         continue; /* blank/comment line */
 770                 }
 771
 772                 if (strcmp(first_word, "mapping") == 0) {
 773 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 774                         currmap = xzalloc(sizeof(*currmap));
 775
 776                         while ((first_word = next_word(&rest_of_line)) != NULL) {
 777                                 currmap->match = xrealloc_vector(currmap->match, 4, currmap->n_matches);
 778                                 currmap->match[currmap->n_matches++] = xstrdup(first_word);
 779                         }
 780                         /*currmap->max_mappings = 0; - done by xzalloc */
 781                         /*currmap->n_mappings = 0;*/
 782                         /*currmap->mapping = NULL;*/
 783                         /*currmap->script = NULL;*/
 784                         {
 785                                 struct mapping_defn_t **where = &defn->mappings;
 786                                 while (*where != NULL) {
 787                                         where = &(*where)->next;
 788                                 }
 789                                 *where = currmap;
 790                                 /*currmap->next = NULL;*/
 791                         }
 792                         debug_noise("Added mapping\n");
 793 #endif
 794                         currently_processing = MAPPING;
 795                 } else if (strcmp(first_word, "iface") == 0) {
 796                         static const struct address_family_t *const addr_fams[] = {
 797 #if ENABLE_FEATURE_IFUPDOWN_IPV4
 798                                 &addr_inet,
 799 #endif
 800 #if ENABLE_FEATURE_IFUPDOWN_IPV6
 801                                 &addr_inet6,
 802 #endif
 803                                 NULL
 804                         };
 805                         char *iface_name;
 806                         char *address_family_name;
 807                         char *method_name;
 808                         llist_t *iface_list;
 809
 810                         currif = xzalloc(sizeof(*currif));
 811                         iface_name = next_word(&rest_of_line);
 812                         address_family_name = next_word(&rest_of_line);
 813                         method_name = next_word(&rest_of_line);
 814
 815                         if (method_name == NULL)
 816                                 bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
 817
 818                         /* ship any trailing whitespace */
 819                         rest_of_line = skip_whitespace(rest_of_line);
 820
 821                         if (rest_of_line[0] != '\0' /* && rest_of_line[0] != '#' */)
 822                                 bb_error_msg_and_die("too many parameters \"%s\"", buf);
 823
 824                         currif->iface = xstrdup(iface_name);
 825
 826                         currif->address_family = get_address_family(addr_fams, address_family_name);
 827                         if (!currif->address_family)
 828                                 bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
 829
 830                         currif->method = get_method(currif->address_family, method_name);
 831                         if (!currif->method)
 832                                 bb_error_msg_and_die("unknown method \"%s\"", method_name);
 833
 834                         for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
 835                                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
 836                                 if ((strcmp(tmp->iface, currif->iface) == 0)
 837                                  && (tmp->address_family == currif->address_family)
 838                                 ) {
 839                                         bb_error_msg_and_die("duplicate interface \"%s\"", tmp->iface);
 840                                 }
 841                         }
 842                         llist_add_to_end(&(defn->ifaces), (char*)currif);
 843
 844                         debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
 845                         currently_processing = IFACE;
 846                 } else if (strcmp(first_word, "auto") == 0) {
 847                         while ((first_word = next_word(&rest_of_line)) != NULL) {
 848
 849                                 /* Check the interface isnt already listed */
 850                                 if (llist_find_str(defn->autointerfaces, first_word)) {
 851                                         bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
 852                                 }
 853
 854                                 /* Add the interface to the list */
 855                                 llist_add_to_end(&(defn->autointerfaces), xstrdup(first_word));
 856                                 debug_noise("\nauto %s\n", first_word);
 857                         }
 858                         currently_processing = NONE;
 859                 } else {
 860                         switch (currently_processing) {
 861                         case IFACE:
 862                                 if (rest_of_line[0] == '\0')
 863                                         bb_error_msg_and_die("option with empty value \"%s\"", buf);
 864
 865                                 if (strcmp(first_word, "up") != 0
 866                                  && strcmp(first_word, "down") != 0
 867                                  && strcmp(first_word, "pre-up") != 0
 868                                  && strcmp(first_word, "post-down") != 0
 869                                 ) {
 870                                         int i;
 871                                         for (i = 0; i < currif->n_options; i++) {
 872                                                 if (strcmp(currif->option[i].name, first_word) == 0)
 873                                                         bb_error_msg_and_die("duplicate option \"%s\"", buf);
 874                                         }
 875                                 }
 876                                 if (currif->n_options >= currif->max_options) {
 877                                         currif->max_options += 10;
 878                                         currif->option = xrealloc(currif->option,
 879                                                 sizeof(*currif->option) * currif->max_options);
 880                                 }
 881                                 debug_noise("\t%s=%s\n", first_word, rest_of_line);
 882                                 currif->option[currif->n_options].name = xstrdup(first_word);
 883                                 currif->option[currif->n_options].value = xstrdup(rest_of_line);
 884                                 currif->n_options++;
 885                                 break;
 886                         case MAPPING:
 887 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 888                                 if (strcmp(first_word, "script") == 0) {
 889                                         if (currmap->script != NULL)
 890                                                 bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
 891                                         currmap->script = xstrdup(next_word(&rest_of_line));
 892                                 } else if (strcmp(first_word, "map") == 0) {
 893                                         if (currmap->n_mappings >= currmap->max_mappings) {
 894                                                 currmap->max_mappings = currmap->max_mappings * 2 + 1;
 895                                                 currmap->mapping = xrealloc(currmap->mapping,
 896                                                         sizeof(char *) * currmap->max_mappings);
 897                                         }
 898                                         currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&rest_of_line));
 899                                         currmap->n_mappings++;
 900                                 } else {
 901                                         bb_error_msg_and_die("misplaced option \"%s\"", buf);
 902                                 }
 903 #endif
 904                                 break;
 905                         case NONE:
 906                         default:
 907                                 bb_error_msg_and_die("misplaced option \"%s\"", buf);
 908                         }
 909                 }
 910                 free(buf);
 911         } /* while (fgets) */
 912
 913         if (ferror(f) != 0) {
 914                 /* ferror does NOT set errno! */
 915                 bb_error_msg_and_die("%s: I/O error", filename);
 916         }
 917         fclose(f);
 918
 919         return defn;
 920 }
 921
 922 static char *setlocalenv(const char *format, const char *name, const char *value)
 923 {
 924         char *result;
 925         char *dst;
 926         char *src;
 927         char c;
 928
 929         result = xasprintf(format, name, value);
 930
 931         for (dst = src = result; (c = *src) != '=' && c; src++) {
 932                 if (c == '-')
 933                         c = '_';
 934                 if (c >= 'a' && c <= 'z')
 935                         c -= ('a' - 'A');
 936                 if (isalnum(c) || c == '_')
 937                         *dst++ = c;
 938         }
 939         overlapping_strcpy(dst, src);
 940
 941         return result;
 942 }
 943
 944 static void set_environ(struct interface_defn_t *iface, const char *mode)
 945 {
 946         int i;
 947         char **pp;
 948
 949         if (G.my_environ != NULL) {
 950                 for (pp = G.my_environ; *pp; pp++) {
 951                         free(*pp);
 952                 }
 953                 free(G.my_environ);
 954         }
 955
 956         /* note: last element will stay NULL: */
 957         G.my_environ = xzalloc(sizeof(char *) * (iface->n_options + 6));
 958         pp = G.my_environ;
 959
 960         for (i = 0; i < iface->n_options; i++) {
 961                 if (strcmp(iface->option[i].name, "up") == 0
 962                  || strcmp(iface->option[i].name, "down") == 0
 963                  || strcmp(iface->option[i].name, "pre-up") == 0
 964                  || strcmp(iface->option[i].name, "post-down") == 0
 965                 ) {
 966                         continue;
 967                 }
 968                 *pp++ = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
 969         }
 970
 971         *pp++ = setlocalenv("%s=%s", "IFACE", iface->iface);
 972         *pp++ = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
 973         *pp++ = setlocalenv("%s=%s", "METHOD", iface->method->name);
 974         *pp++ = setlocalenv("%s=%s", "MODE", mode);
 975         if (G.startup_PATH)
 976                 *pp++ = setlocalenv("%s=%s", "PATH", G.startup_PATH);
 977 }
 978
 979 static int doit(char *str)
 980 {
 981         if (option_mask32 & (OPT_no_act|OPT_verbose)) {
 982                 puts(str);
 983         }
 984         if (!(option_mask32 & OPT_no_act)) {
 985                 pid_t child;
 986                 int status;
 987
 988                 fflush_all();
 989                 child = vfork();
 990                 if (child < 0) /* failure */
 991                         return 0;
 992                 if (child == 0) { /* child */
 993                         execle(G.shell, G.shell, "-c", str, (char *) NULL, G.my_environ);
 994                         _exit(127);
 995                 }
 996                 safe_waitpid(child, &status, 0);
 997                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 998                         return 0;
 999                 }
1000         }
1001         return 1;
1002 }
1003
1004 static int execute_all(struct interface_defn_t *ifd, const char *opt)
1005 {
1006         int i;
1007         char *buf;
1008         for (i = 0; i < ifd->n_options; i++) {
1009                 if (strcmp(ifd->option[i].name, opt) == 0) {
1010                         if (!doit(ifd->option[i].value)) {
1011                                 return 0;
1012                         }
1013                 }
1014         }
1015
1016         buf = xasprintf("run-parts /etc/network/if-%s.d", opt);
1017         /* heh, we don't bother free'ing it */
1018         return doit(buf);
1019 }
1020
1021 static int check(char *str)
1022 {
1023         return str != NULL;
1024 }
1025
1026 static int iface_up(struct interface_defn_t *iface)
1027 {
1028         if (!iface->method->up(iface, check)) return -1;
1029         set_environ(iface, "start");
1030         if (!execute_all(iface, "pre-up")) return 0;
1031         if (!iface->method->up(iface, doit)) return 0;
1032         if (!execute_all(iface, "up")) return 0;
1033         return 1;
1034 }
1035
1036 static int iface_down(struct interface_defn_t *iface)
1037 {
1038         if (!iface->method->down(iface,check)) return -1;
1039         set_environ(iface, "stop");
1040         if (!execute_all(iface, "down")) return 0;
1041         if (!iface->method->down(iface, doit)) return 0;
1042         if (!execute_all(iface, "post-down")) return 0;
1043         return 1;
1044 }
1045
1046 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1047 static int popen2(FILE **in, FILE **out, char *command, char *param)
1048 {
1049         char *argv[3] = { command, param, NULL };
1050         struct fd_pair infd, outfd;
1051         pid_t pid;
1052
1053         xpiped_pair(infd);
1054         xpiped_pair(outfd);
1055
1056         fflush_all();
1057         pid = xvfork();
1058
1059         if (pid == 0) {
1060                 /* Child */
1061                 /* NB: close _first_, then move fds! */
1062                 close(infd.wr);
1063                 close(outfd.rd);
1064                 xmove_fd(infd.rd, 0);
1065                 xmove_fd(outfd.wr, 1);
1066                 BB_EXECVP_or_die(argv);
1067         }
1068         /* parent */
1069         close(infd.rd);
1070         close(outfd.wr);
1071         *in = xfdopen_for_write(infd.wr);
1072         *out = xfdopen_for_read(outfd.rd);
1073         return pid;
1074 }
1075
1076 static char *run_mapping(char *physical, struct mapping_defn_t *map)
1077 {
1078         FILE *in, *out;
1079         int i, status;
1080         pid_t pid;
1081
1082         char *logical = xstrdup(physical);
1083
1084         /* Run the mapping script. Never fails. */
1085         pid = popen2(&in, &out, map->script, physical);
1086
1087         /* Write mappings to stdin of mapping script. */
1088         for (i = 0; i < map->n_mappings; i++) {
1089                 fprintf(in, "%s\n", map->mapping[i]);
1090         }
1091         fclose(in);
1092         safe_waitpid(pid, &status, 0);
1093
1094         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
1095                 /* If the mapping script exited successfully, try to
1096                  * grab a line of output and use that as the name of the
1097                  * logical interface. */
1098                 char *new_logical = xmalloc_fgetline(out);
1099
1100                 if (new_logical) {
1101                         /* If we are able to read a line of output from the script,
1102                          * remove any trailing whitespace and use this value
1103                          * as the name of the logical interface. */
1104                         char *pch = new_logical + strlen(new_logical) - 1;
1105
1106                         while (pch >= new_logical && isspace(*pch))
1107                                 *(pch--) = '\0';
1108
1109                         free(logical);
1110                         logical = new_logical;
1111                 }
1112         }
1113
1114         fclose(out);
1115
1116         return logical;
1117 }
1118 #endif /* FEATURE_IFUPDOWN_MAPPING */
1119
1120 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
1121 {
1122         unsigned iface_len = strlen(iface);
1123         llist_t *search = state_list;
1124
1125         while (search) {
1126                 if ((strncmp(search->data, iface, iface_len) == 0)
1127                  && (search->data[iface_len] == '=')
1128                 ) {
1129                         return search;
1130                 }
1131                 search = search->link;
1132         }
1133         return NULL;
1134 }
1135
1136 /* read the previous state from the state file */
1137 static llist_t *read_iface_state(void)
1138 {
1139         llist_t *state_list = NULL;
1140         FILE *state_fp = fopen_for_read(CONFIG_IFUPDOWN_IFSTATE_PATH);
1141
1142         if (state_fp) {
1143                 char *start, *end_ptr;
1144                 while ((start = xmalloc_fgets(state_fp)) != NULL) {
1145                         /* We should only need to check for a single character */
1146                         end_ptr = start + strcspn(start, " \t\n");
1147                         *end_ptr = '\0';
1148                         llist_add_to(&state_list, start);
1149                 }
1150                 fclose(state_fp);
1151         }
1152         return state_list;
1153 }
1154
1155
1156 int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1157 int ifupdown_main(int argc UNUSED_PARAM, char **argv)
1158 {
1159         int (*cmds)(struct interface_defn_t *);
1160         struct interfaces_file_t *defn;
1161         llist_t *target_list = NULL;
1162         const char *interfaces = "/etc/network/interfaces";
1163         bool any_failures = 0;
1164
1165         INIT_G();
1166
1167         G.startup_PATH = getenv("PATH");
1168         G.shell = xstrdup(get_shell_name());
1169
1170         cmds = iface_down;
1171         if (applet_name[2] == 'u') {
1172                 /* ifup command */
1173                 cmds = iface_up;
1174         }
1175
1176         getopt32(argv, OPTION_STR, &interfaces);
1177         argv += optind;
1178         if (argv[0]) {
1179                 if (DO_ALL) bb_show_usage();
1180         } else {
1181                 if (!DO_ALL) bb_show_usage();
1182         }
1183
1184         debug_noise("reading %s file:\n", interfaces);
1185         defn = read_interfaces(interfaces);
1186         debug_noise("\ndone reading %s\n\n", interfaces);
1187
1188         /* Create a list of interfaces to work on */
1189         if (DO_ALL) {
1190                 target_list = defn->autointerfaces;
1191         } else {
1192                 llist_add_to_end(&target_list, argv[0]);
1193         }
1194
1195         /* Update the interfaces */
1196         while (target_list) {
1197                 llist_t *iface_list;
1198                 struct interface_defn_t *currif;
1199                 char *iface;
1200                 char *liface;
1201                 char *pch;
1202                 bool okay = 0;
1203                 int cmds_ret;
1204
1205                 iface = xstrdup(target_list->data);
1206                 target_list = target_list->link;
1207
1208                 pch = strchr(iface, '=');
1209                 if (pch) {
1210                         *pch = '\0';
1211                         liface = xstrdup(pch + 1);
1212                 } else {
1213                         liface = xstrdup(iface);
1214                 }
1215
1216                 if (!FORCE) {
1217                         llist_t *state_list = read_iface_state();
1218                         const llist_t *iface_state = find_iface_state(state_list, iface);
1219
1220                         if (cmds == iface_up) {
1221                                 /* ifup */
1222                                 if (iface_state) {
1223                                         bb_error_msg("interface %s already configured", iface);
1224                                         goto next;
1225                                 }
1226                         } else {
1227                                 /* ifdown */
1228                                 if (!iface_state) {
1229                                         bb_error_msg("interface %s not configured", iface);
1230                                         goto next;
1231                                 }
1232                         }
1233                         llist_free(state_list, free);
1234                 }
1235
1236 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1237                 if ((cmds == iface_up) && !NO_MAPPINGS) {
1238                         struct mapping_defn_t *currmap;
1239
1240                         for (currmap = defn->mappings; currmap; currmap = currmap->next) {
1241                                 int i;
1242                                 for (i = 0; i < currmap->n_matches; i++) {
1243                                         if (fnmatch(currmap->match[i], liface, 0) != 0)
1244                                                 continue;
1245                                         if (VERBOSE) {
1246                                                 printf("Running mapping script %s on %s\n", currmap->script, liface);
1247                                         }
1248                                         liface = run_mapping(iface, currmap);
1249                                         break;
1250                                 }
1251                         }
1252                 }
1253 #endif
1254
1255                 iface_list = defn->ifaces;
1256                 while (iface_list) {
1257                         currif = (struct interface_defn_t *) iface_list->data;
1258                         if (strcmp(liface, currif->iface) == 0) {
1259                                 char *oldiface = currif->iface;
1260
1261                                 okay = 1;
1262                                 currif->iface = iface;
1263
1264                                 debug_noise("\nConfiguring interface %s (%s)\n", liface, currif->address_family->name);
1265
1266                                 /* Call the cmds function pointer, does either iface_up() or iface_down() */
1267                                 cmds_ret = cmds(currif);
1268                                 if (cmds_ret == -1) {
1269                                         bb_error_msg("don't seem to have all the variables for %s/%s",
1270                                                         liface, currif->address_family->name);
1271                                         any_failures = 1;
1272                                 } else if (cmds_ret == 0) {
1273                                         any_failures = 1;
1274                                 }
1275
1276                                 currif->iface = oldiface;
1277                         }
1278                         iface_list = iface_list->link;
1279                 }
1280                 if (VERBOSE) {
1281                         bb_putchar('\n');
1282                 }
1283
1284                 if (!okay && !FORCE) {
1285                         bb_error_msg("ignoring unknown interface %s", liface);
1286                         any_failures = 1;
1287                 } else if (!NO_ACT) {
1288                         /* update the state file */
1289                         FILE *state_fp;
1290                         llist_t *state;
1291                         llist_t *state_list = read_iface_state();
1292                         llist_t *iface_state = find_iface_state(state_list, iface);
1293
1294                         if (cmds == iface_up) {
1295                                 char * const newiface = xasprintf("%s=%s", iface, liface);
1296                                 if (iface_state == NULL) {
1297                                         llist_add_to_end(&state_list, newiface);
1298                                 } else {
1299                                         free(iface_state->data);
1300                                         iface_state->data = newiface;
1301                                 }
1302                         } else {
1303                                 /* Remove an interface from state_list */
1304                                 llist_unlink(&state_list, iface_state);
1305                                 free(llist_pop(&iface_state));
1306                         }
1307
1308                         /* Actually write the new state */
1309                         state_fp = xfopen_for_write(CONFIG_IFUPDOWN_IFSTATE_PATH);
1310                         state = state_list;
1311                         while (state) {
1312                                 if (state->data) {
1313                                         fprintf(state_fp, "%s\n", state->data);
1314                                 }
1315                                 state = state->link;
1316                         }
1317                         fclose(state_fp);
1318                         llist_free(state_list, free);
1319                 }
1320  next:
1321                 free(iface);
1322                 free(liface);
1323         }
1324
1325         return any_failures;
1326 }