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 //usage:#define ifup_trivial_usage
  21 //usage:       "[-an"IF_FEATURE_IFUPDOWN_MAPPING("m")"vf] [-i FILE] IFACE..."
  22 //usage:#define ifup_full_usage "\n\n"
  23 //usage:       "        -a      De/configure all interfaces automatically"
  24 //usage:     "\n        -i FILE Use FILE for interface definitions"
  25 //usage:     "\n        -n      Print out what would happen, but don't do it"
  26 //usage:        IF_FEATURE_IFUPDOWN_MAPPING(
  27 //usage:     "\n                (note: doesn't disable mappings)"
  28 //usage:     "\n        -m      Don't run any mappings"
  29 //usage:        )
  30 //usage:     "\n        -v      Print out what would happen before doing it"
  31 //usage:     "\n        -f      Force de/configuration"
  32 //usage:
  33 //usage:#define ifdown_trivial_usage
  34 //usage:       "[-an"IF_FEATURE_IFUPDOWN_MAPPING("m")"vf] [-i FILE] IFACE..."
  35 //usage:#define ifdown_full_usage "\n\n"
  36 //usage:       "        -a      De/configure all interfaces automatically"
  37 //usage:     "\n        -i FILE Use FILE for interface definitions"
  38 //usage:     "\n        -n      Print out what would happen, but don't do it"
  39 //usage:        IF_FEATURE_IFUPDOWN_MAPPING(
  40 //usage:     "\n                (note: doesn't disable mappings)"
  41 //usage:     "\n        -m      Don't run any mappings"
  42 //usage:        )
  43 //usage:     "\n        -v      Print out what would happen before doing it"
  44 //usage:     "\n        -f      Force de/configuration"
  45
  46 #include "libbb.h"
  47 /* After libbb.h, since it needs sys/types.h on some systems */
  48 #include <sys/utsname.h>
  49 #include <fnmatch.h>
  50
  51 #define MAX_OPT_DEPTH 10
  52
  53 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
  54 #define MAX_INTERFACE_LENGTH 10
  55 #endif
  56
  57 #define UDHCPC_CMD_OPTIONS CONFIG_IFUPDOWN_UDHCPC_CMD_OPTIONS
  58
  59 #define debug_noise(args...) /*fprintf(stderr, args)*/
  60
  61 /* Forward declaration */
  62 struct interface_defn_t;
  63
  64 typedef int execfn(char *command);
  65
  66 struct method_t {
  67         const char *name;
  68         int (*up)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
  69         int (*down)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
  70 };
  71
  72 struct address_family_t {
  73         const char *name;
  74         int n_methods;
  75         const struct method_t *method;
  76 };
  77
  78 struct mapping_defn_t {
  79         struct mapping_defn_t *next;
  80
  81         int max_matches;
  82         int n_matches;
  83         char **match;
  84
  85         char *script;
  86
  87         int n_mappings;
  88         char **mapping;
  89 };
  90
  91 struct variable_t {
  92         char *name;
  93         char *value;
  94 };
  95
  96 struct interface_defn_t {
  97         const struct address_family_t *address_family;
  98         const struct method_t *method;
  99
 100         char *iface;
 101         int n_options;
 102         struct variable_t *option;
 103 };
 104
 105 struct interfaces_file_t {
 106         llist_t *autointerfaces;
 107         llist_t *ifaces;
 108         struct mapping_defn_t *mappings;
 109 };
 110
 111
 112 #define OPTION_STR "anvf" IF_FEATURE_IFUPDOWN_MAPPING("m") "i:"
 113 enum {
 114         OPT_do_all      = 0x1,
 115         OPT_no_act      = 0x2,
 116         OPT_verbose     = 0x4,
 117         OPT_force       = 0x8,
 118         OPT_no_mappings = 0x10,
 119 };
 120 #define DO_ALL      (option_mask32 & OPT_do_all)
 121 #define NO_ACT      (option_mask32 & OPT_no_act)
 122 #define VERBOSE     (option_mask32 & OPT_verbose)
 123 #define FORCE       (option_mask32 & OPT_force)
 124 #define NO_MAPPINGS (option_mask32 & OPT_no_mappings)
 125
 126
 127 struct globals {
 128         char **my_environ;
 129         const char *startup_PATH;
 130         char *shell;
 131 } FIX_ALIASING;
 132 #define G (*(struct globals*)&bb_common_bufsiz1)
 133 #define INIT_G() do { } while (0)
 134
 135
 136 static const char keywords_up_down[] ALIGN1 =
 137         "up\0"
 138         "down\0"
 139         "pre-up\0"
 140         "post-down\0"
 141 ;
 142
 143
 144 #if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
 145
 146 static void addstr(char **bufp, const char *str, size_t str_length)
 147 {
 148         /* xasprintf trick will be smaller, but we are often
 149          * called with str_length == 1 - don't want to have
 150          * THAT much of malloc/freeing! */
 151         char *buf = *bufp;
 152         int len = (buf ? strlen(buf) : 0);
 153         str_length++;
 154         buf = xrealloc(buf, len + str_length);
 155         /* copies at most str_length-1 chars! */
 156         safe_strncpy(buf + len, str, str_length);
 157         *bufp = buf;
 158 }
 159
 160 static int strncmpz(const char *l, const char *r, size_t llen)
 161 {
 162         int i = strncmp(l, r, llen);
 163
 164         if (i == 0)
 165                 return - (unsigned char)r[llen];
 166         return i;
 167 }
 168
 169 static char *get_var(const char *id, size_t idlen, struct interface_defn_t *ifd)
 170 {
 171         int i;
 172
 173         if (strncmpz(id, "iface", idlen) == 0) {
 174                 // ubuntu's ifup doesn't do this:
 175                 //static char *label_buf;
 176                 //char *result;
 177                 //free(label_buf);
 178                 //label_buf = xstrdup(ifd->iface);
 179                 // Remove virtual iface suffix
 180                 //result = strchrnul(label_buf, ':');
 181                 //*result = '\0';
 182                 //return label_buf;
 183
 184                 return ifd->iface;
 185         }
 186         if (strncmpz(id, "label", idlen) == 0) {
 187                 return ifd->iface;
 188         }
 189         for (i = 0; i < ifd->n_options; i++) {
 190                 if (strncmpz(id, ifd->option[i].name, idlen) == 0) {
 191                         return ifd->option[i].value;
 192                 }
 193         }
 194         return NULL;
 195 }
 196
 197 # if ENABLE_FEATURE_IFUPDOWN_IP
 198 static int count_netmask_bits(const char *dotted_quad)
 199 {
 200 //      int result;
 201 //      unsigned a, b, c, d;
 202 //      /* Found a netmask...  Check if it is dotted quad */
 203 //      if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
 204 //              return -1;
 205 //      if ((a|b|c|d) >> 8)
 206 //              return -1; /* one of numbers is >= 256 */
 207 //      d |= (a << 24) | (b << 16) | (c << 8); /* IP */
 208 //      d = ~d; /* 11110000 -> 00001111 */
 209
 210         /* Shorter version */
 211         int result;
 212         struct in_addr ip;
 213         unsigned d;
 214
 215         if (inet_aton(dotted_quad, &ip) == 0)
 216                 return -1; /* malformed dotted IP */
 217         d = ntohl(ip.s_addr); /* IP in host order */
 218         d = ~d; /* 11110000 -> 00001111 */
 219         if (d & (d+1)) /* check that it is in 00001111 form */
 220                 return -1; /* no it is not */
 221         result = 32;
 222         while (d) {
 223                 d >>= 1;
 224                 result--;
 225         }
 226         return result;
 227 }
 228 # endif
 229
 230 static char *parse(const char *command, struct interface_defn_t *ifd)
 231 {
 232         size_t old_pos[MAX_OPT_DEPTH] = { 0 };
 233         smallint okay[MAX_OPT_DEPTH] = { 1 };
 234         int opt_depth = 1;
 235         char *result = NULL;
 236
 237         while (*command) {
 238                 switch (*command) {
 239                 default:
 240                         addstr(&result, command, 1);
 241                         command++;
 242                         break;
 243                 case '\\':
 244                         if (command[1])
 245                                 command++;
 246                         addstr(&result, command, 1);
 247                         command++;
 248                         break;
 249                 case '[':
 250                         if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
 251                                 old_pos[opt_depth] = result ? strlen(result) : 0;
 252                                 okay[opt_depth] = 1;
 253                                 opt_depth++;
 254                                 command += 2;
 255                         } else {
 256                                 addstr(&result, command, 1);
 257                                 command++;
 258                         }
 259                         break;
 260                 case ']':
 261                         if (command[1] == ']' && opt_depth > 1) {
 262                                 opt_depth--;
 263                                 if (!okay[opt_depth]) {
 264                                         result[old_pos[opt_depth]] = '\0';
 265                                 }
 266                                 command += 2;
 267                         } else {
 268                                 addstr(&result, command, 1);
 269                                 command++;
 270                         }
 271                         break;
 272                 case '%':
 273                         {
 274                                 char *nextpercent;
 275                                 char *varvalue;
 276
 277                                 command++;
 278                                 nextpercent = strchr(command, '%');
 279                                 if (!nextpercent) {
 280                                         /* Unterminated %var% */
 281                                         free(result);
 282                                         return NULL;
 283                                 }
 284
 285                                 varvalue = get_var(command, nextpercent - command, ifd);
 286
 287                                 if (varvalue) {
 288 # if ENABLE_FEATURE_IFUPDOWN_IP
 289                                         /* "hwaddress <class> <address>":
 290                                          * unlike ifconfig, ip doesnt want <class>
 291                                          * (usually "ether" keyword). Skip it. */
 292                                         if (strncmp(command, "hwaddress", 9) == 0) {
 293                                                 varvalue = skip_whitespace(skip_non_whitespace(varvalue));
 294                                         }
 295 # endif
 296                                         addstr(&result, varvalue, strlen(varvalue));
 297                                 } else {
 298 # if ENABLE_FEATURE_IFUPDOWN_IP
 299                                         /* Sigh...  Add a special case for 'ip' to convert from
 300                                          * dotted quad to bit count style netmasks.  */
 301                                         if (strncmp(command, "bnmask", 6) == 0) {
 302                                                 unsigned res;
 303                                                 varvalue = get_var("netmask", 7, ifd);
 304                                                 if (varvalue) {
 305                                                         res = count_netmask_bits(varvalue);
 306                                                         if (res > 0) {
 307                                                                 const char *argument = utoa(res);
 308                                                                 addstr(&result, argument, strlen(argument));
 309                                                                 command = nextpercent + 1;
 310                                                                 break;
 311                                                         }
 312                                                 }
 313                                         }
 314 # endif
 315                                         okay[opt_depth - 1] = 0;
 316                                 }
 317
 318                                 command = nextpercent + 1;
 319                         }
 320                         break;
 321                 }
 322         }
 323
 324         if (opt_depth > 1) {
 325                 /* Unbalanced bracket */
 326                 free(result);
 327                 return NULL;
 328         }
 329
 330         if (!okay[0]) {
 331                 /* Undefined variable and we aren't in a bracket */
 332                 free(result);
 333                 return NULL;
 334         }
 335
 336         return result;
 337 }
 338
 339 /* execute() returns 1 for success and 0 for failure */
 340 static int execute(const char *command, struct interface_defn_t *ifd, execfn *exec)
 341 {
 342         char *out;
 343         int ret;
 344
 345         out = parse(command, ifd);
 346         if (!out) {
 347                 /* parse error? */
 348                 return 0;
 349         }
 350         /* out == "": parsed ok but not all needed variables known, skip */
 351         ret = out[0] ? (*exec)(out) : 1;
 352
 353         free(out);
 354         if (ret != 1) {
 355                 return 0;
 356         }
 357         return 1;
 358 }
 359
 360 #endif /* FEATURE_IFUPDOWN_IPV4 || FEATURE_IFUPDOWN_IPV6 */
 361
 362
 363 #if ENABLE_FEATURE_IFUPDOWN_IPV6
 364
 365 static int FAST_FUNC loopback_up6(struct interface_defn_t *ifd, execfn *exec)
 366 {
 367 # if ENABLE_FEATURE_IFUPDOWN_IP
 368         int result;
 369         result = execute("ip addr add ::1 dev %iface%", ifd, exec);
 370         result += execute("ip link set %iface% up", ifd, exec);
 371         return ((result == 2) ? 2 : 0);
 372 # else
 373         return execute("ifconfig %iface% add ::1", ifd, exec);
 374 # endif
 375 }
 376
 377 static int FAST_FUNC loopback_down6(struct interface_defn_t *ifd, execfn *exec)
 378 {
 379 # if ENABLE_FEATURE_IFUPDOWN_IP
 380         return execute("ip link set %iface% down", ifd, exec);
 381 # else
 382         return execute("ifconfig %iface% del ::1", ifd, exec);
 383 # endif
 384 }
 385
 386 static int FAST_FUNC manual_up_down6(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 387 {
 388         return 1;
 389 }
 390
 391 static int FAST_FUNC static_up6(struct interface_defn_t *ifd, execfn *exec)
 392 {
 393         int result;
 394 # if ENABLE_FEATURE_IFUPDOWN_IP
 395         result = execute("ip addr add %address%/%netmask% dev %iface%[[ label %label%]]", ifd, exec);
 396         result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
 397         /* Was: "[[ ip ....%gateway% ]]". Removed extra spaces w/o checking */
 398         result += execute("[[ip route add ::/0 via %gateway%]][[ prio %metric%]]", ifd, exec);
 399 # else
 400         result = execute("ifconfig %iface%[[ media %media%]][[ hw %hwaddress%]][[ mtu %mtu%]] up", ifd, exec);
 401         result += execute("ifconfig %iface% add %address%/%netmask%", ifd, exec);
 402         result += execute("[[route -A inet6 add ::/0 gw %gateway%[[ metric %metric%]]]]", ifd, exec);
 403 # endif
 404         return ((result == 3) ? 3 : 0);
 405 }
 406
 407 static int FAST_FUNC static_down6(struct interface_defn_t *ifd, execfn *exec)
 408 {
 409 # if ENABLE_FEATURE_IFUPDOWN_IP
 410         return execute("ip link set %iface% down", ifd, exec);
 411 # else
 412         return execute("ifconfig %iface% down", ifd, exec);
 413 # endif
 414 }
 415
 416 # if ENABLE_FEATURE_IFUPDOWN_IP
 417 static int FAST_FUNC v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
 418 {
 419         int result;
 420         result = execute("ip tunnel add %iface% mode sit remote "
 421                         "%endpoint%[[ local %local%]][[ ttl %ttl%]]", ifd, exec);
 422         result += execute("ip link set %iface% up", ifd, exec);
 423         result += execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec);
 424         result += execute("[[ip route add ::/0 via %gateway%]]", ifd, exec);
 425         return ((result == 4) ? 4 : 0);
 426 }
 427
 428 static int FAST_FUNC v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
 429 {
 430         return execute("ip tunnel del %iface%", ifd, exec);
 431 }
 432 # endif
 433
 434 static const struct method_t methods6[] = {
 435 # if ENABLE_FEATURE_IFUPDOWN_IP
 436         { "v4tunnel" , v4tunnel_up     , v4tunnel_down   , },
 437 # endif
 438         { "static"   , static_up6      , static_down6    , },
 439         { "manual"   , manual_up_down6 , manual_up_down6 , },
 440         { "loopback" , loopback_up6    , loopback_down6  , },
 441 };
 442
 443 static const struct address_family_t addr_inet6 = {
 444         "inet6",
 445         ARRAY_SIZE(methods6),
 446         methods6
 447 };
 448
 449 #endif /* FEATURE_IFUPDOWN_IPV6 */
 450
 451
 452 #if ENABLE_FEATURE_IFUPDOWN_IPV4
 453
 454 static int FAST_FUNC loopback_up(struct interface_defn_t *ifd, execfn *exec)
 455 {
 456 # if ENABLE_FEATURE_IFUPDOWN_IP
 457         int result;
 458         result = execute("ip addr add 127.0.0.1/8 dev %iface%", ifd, exec);
 459         result += execute("ip link set %iface% up", ifd, exec);
 460         return ((result == 2) ? 2 : 0);
 461 # else
 462         return execute("ifconfig %iface% 127.0.0.1 up", ifd, exec);
 463 # endif
 464 }
 465
 466 static int FAST_FUNC loopback_down(struct interface_defn_t *ifd, execfn *exec)
 467 {
 468 # if ENABLE_FEATURE_IFUPDOWN_IP
 469         int result;
 470         result = execute("ip addr flush dev %iface%", ifd, exec);
 471         result += execute("ip link set %iface% down", ifd, exec);
 472         return ((result == 2) ? 2 : 0);
 473 # else
 474         return execute("ifconfig %iface% 127.0.0.1 down", ifd, exec);
 475 # endif
 476 }
 477
 478 static int FAST_FUNC static_up(struct interface_defn_t *ifd, execfn *exec)
 479 {
 480         int result;
 481 # if ENABLE_FEATURE_IFUPDOWN_IP
 482         result = execute("ip addr add %address%/%bnmask%[[ broadcast %broadcast%]] "
 483                         "dev %iface%[[ peer %pointopoint%]][[ label %label%]]", ifd, exec);
 484         result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
 485         result += execute("[[ip route add default via %gateway% dev %iface%[[ prio %metric%]]]]", ifd, exec);
 486         return ((result == 3) ? 3 : 0);
 487 # else
 488         /* ifconfig said to set iface up before it processes hw %hwaddress%,
 489          * which then of course fails. Thus we run two separate ifconfig */
 490         result = execute("ifconfig %iface%[[ hw %hwaddress%]][[ media %media%]][[ mtu %mtu%]] up",
 491                                 ifd, exec);
 492         result += execute("ifconfig %iface% %address% netmask %netmask%"
 493                                 "[[ broadcast %broadcast%]][[ pointopoint %pointopoint%]] ",
 494                                 ifd, exec);
 495         result += execute("[[route add default gw %gateway%[[ metric %metric%]] %iface%]]", ifd, exec);
 496         return ((result == 3) ? 3 : 0);
 497 # endif
 498 }
 499
 500 static int FAST_FUNC static_down(struct interface_defn_t *ifd, execfn *exec)
 501 {
 502         int result;
 503 # if ENABLE_FEATURE_IFUPDOWN_IP
 504         result = execute("ip addr flush dev %iface%", ifd, exec);
 505         result += execute("ip link set %iface% down", ifd, exec);
 506 # else
 507         /* result = execute("[[route del default gw %gateway% %iface%]]", ifd, exec); */
 508         /* Bringing the interface down deletes the routes in itself.
 509            Otherwise this fails if we reference 'gateway' when using this from dhcp_down */
 510         result = 1;
 511         result += execute("ifconfig %iface% down", ifd, exec);
 512 # endif
 513         return ((result == 2) ? 2 : 0);
 514 }
 515
 516 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 517 struct dhcp_client_t {
 518         const char *name;
 519         const char *startcmd;
 520         const char *stopcmd;
 521 };
 522
 523 static const struct dhcp_client_t ext_dhcp_clients[] = {
 524         { "dhcpcd",
 525                 "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %client%]][[ -l %leasetime%]] %iface%",
 526                 "dhcpcd -k %iface%",
 527         },
 528         { "dhclient",
 529                 "dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
 530                 "kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
 531         },
 532         { "pump",
 533                 "pump -i %iface%[[ -h %hostname%]][[ -l %leasehours%]]",
 534                 "pump -i %iface% -k",
 535         },
 536         { "udhcpc",
 537                 "udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %client%]]"
 538                                 "[[ -s %script%]][[ %udhcpc_opts%]]",
 539                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
 540         },
 541 };
 542 # endif /* FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
 543
 544 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 545 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 546 {
 547         unsigned i;
 548 #  if ENABLE_FEATURE_IFUPDOWN_IP
 549         /* ip doesn't up iface when it configures it (unlike ifconfig) */
 550         if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
 551                 return 0;
 552 #  else
 553         /* needed if we have hwaddress on dhcp iface */
 554         if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
 555                 return 0;
 556 #  endif
 557         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
 558                 if (exists_execable(ext_dhcp_clients[i].name))
 559                         return execute(ext_dhcp_clients[i].startcmd, ifd, exec);
 560         }
 561         bb_error_msg("no dhcp clients found");
 562         return 0;
 563 }
 564 # elif ENABLE_UDHCPC
 565 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 566 {
 567 #  if ENABLE_FEATURE_IFUPDOWN_IP
 568         /* ip doesn't up iface when it configures it (unlike ifconfig) */
 569         if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
 570                 return 0;
 571 #  else
 572         /* needed if we have hwaddress on dhcp iface */
 573         if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
 574                 return 0;
 575 #  endif
 576         return execute("udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid "
 577                         "-i %iface%[[ -H %hostname%]][[ -c %client%]][[ -s %script%]][[ %udhcpc_opts%]]",
 578                         ifd, exec);
 579 }
 580 # else
 581 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd UNUSED_PARAM,
 582                 execfn *exec UNUSED_PARAM)
 583 {
 584         return 0; /* no dhcp support */
 585 }
 586 # endif
 587
 588 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 589 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 590 {
 591         int result = 0;
 592         unsigned i;
 593
 594         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
 595                 if (exists_execable(ext_dhcp_clients[i].name)) {
 596                         result = execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
 597                         if (result)
 598                                 break;
 599                 }
 600         }
 601
 602         if (!result)
 603                 bb_error_msg("warning: no dhcp clients found and stopped");
 604
 605         /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
 606            and it may come back up because udhcpc is still shutting down */
 607         usleep(100000);
 608         result += static_down(ifd, exec);
 609         return ((result == 3) ? 3 : 0);
 610 }
 611 # elif ENABLE_UDHCPC
 612 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 613 {
 614         int result;
 615         result = execute(
 616                 "test -f /var/run/udhcpc.%iface%.pid && "
 617                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
 618                 ifd, exec);
 619         /* Also bring the hardware interface down since
 620            killing the dhcp client alone doesn't do it.
 621            This enables consecutive ifup->ifdown->ifup */
 622         /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
 623            and it may come back up because udhcpc is still shutting down */
 624         usleep(100000);
 625         result += static_down(ifd, exec);
 626         return ((result == 3) ? 3 : 0);
 627 }
 628 # else
 629 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd UNUSED_PARAM,
 630                 execfn *exec UNUSED_PARAM)
 631 {
 632         return 0; /* no dhcp support */
 633 }
 634 # endif
 635
 636 static int FAST_FUNC manual_up_down(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 637 {
 638         return 1;
 639 }
 640
 641 static int FAST_FUNC bootp_up(struct interface_defn_t *ifd, execfn *exec)
 642 {
 643         return execute("bootpc[[ --bootfile %bootfile%]] --dev %iface%"
 644                         "[[ --server %server%]][[ --hwaddr %hwaddr%]]"
 645                         " --returniffail --serverbcast", ifd, exec);
 646 }
 647
 648 static int FAST_FUNC ppp_up(struct interface_defn_t *ifd, execfn *exec)
 649 {
 650         return execute("pon[[ %provider%]]", ifd, exec);
 651 }
 652
 653 static int FAST_FUNC ppp_down(struct interface_defn_t *ifd, execfn *exec)
 654 {
 655         return execute("poff[[ %provider%]]", ifd, exec);
 656 }
 657
 658 static int FAST_FUNC wvdial_up(struct interface_defn_t *ifd, execfn *exec)
 659 {
 660         return execute("start-stop-daemon --start -x wvdial "
 661                 "-p /var/run/wvdial.%iface% -b -m --[[ %provider%]]", ifd, exec);
 662 }
 663
 664 static int FAST_FUNC wvdial_down(struct interface_defn_t *ifd, execfn *exec)
 665 {
 666         return execute("start-stop-daemon --stop -x wvdial "
 667                         "-p /var/run/wvdial.%iface% -s 2", ifd, exec);
 668 }
 669
 670 static const struct method_t methods[] = {
 671         { "manual"  , manual_up_down, manual_up_down, },
 672         { "wvdial"  , wvdial_up     , wvdial_down   , },
 673         { "ppp"     , ppp_up        , ppp_down      , },
 674         { "static"  , static_up     , static_down   , },
 675         { "bootp"   , bootp_up      , static_down   , },
 676         { "dhcp"    , dhcp_up       , dhcp_down     , },
 677         { "loopback", loopback_up   , loopback_down , },
 678 };
 679
 680 static const struct address_family_t addr_inet = {
 681         "inet",
 682         ARRAY_SIZE(methods),
 683         methods
 684 };
 685
 686 #endif  /* FEATURE_IFUPDOWN_IPV4 */
 687
 688 static int FAST_FUNC link_up_down(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 689 {
 690         return 1;
 691 }
 692
 693 static const struct method_t link_methods[] = {
 694         { "none", link_up_down, link_up_down }
 695 };
 696
 697 static const struct address_family_t addr_link = {
 698         "link", ARRAY_SIZE(link_methods), link_methods
 699 };
 700
 701 /* Returns pointer to the next word, or NULL.
 702  * In 1st case, advances *buf to the word after this one.
 703  */
 704 static char *next_word(char **buf)
 705 {
 706         unsigned length;
 707         char *word;
 708
 709         /* Skip over leading whitespace */
 710         word = skip_whitespace(*buf);
 711
 712         /* Stop on EOL */
 713         if (*word == '\0')
 714                 return NULL;
 715
 716         /* Find the length of this word (can't be 0) */
 717         length = strcspn(word, " \t\n");
 718
 719         /* Unless we are already at NUL, store NUL and advance */
 720         if (word[length] != '\0')
 721                 word[length++] = '\0';
 722
 723         *buf = skip_whitespace(word + length);
 724
 725         return word;
 726 }
 727
 728 static const struct address_family_t *get_address_family(const struct address_family_t *const af[], char *name)
 729 {
 730         int i;
 731
 732         if (!name)
 733                 return NULL;
 734
 735         for (i = 0; af[i]; i++) {
 736                 if (strcmp(af[i]->name, name) == 0) {
 737                         return af[i];
 738                 }
 739         }
 740         return NULL;
 741 }
 742
 743 static const struct method_t *get_method(const struct address_family_t *af, char *name)
 744 {
 745         int i;
 746
 747         if (!name)
 748                 return NULL;
 749         /* TODO: use index_in_str_array() */
 750         for (i = 0; i < af->n_methods; i++) {
 751                 if (strcmp(af->method[i].name, name) == 0) {
 752                         return &af->method[i];
 753                 }
 754         }
 755         return NULL;
 756 }
 757
 758 static struct interfaces_file_t *read_interfaces(const char *filename, struct interfaces_file_t *defn)
 759 {
 760         /* Let's try to be compatible.
 761          *
 762          * "man 5 interfaces" says:
 763          * Lines starting with "#" are ignored. Note that end-of-line
 764          * comments are NOT supported, comments must be on a line of their own.
 765          * A line may be extended across multiple lines by making
 766          * the last character a backslash.
 767          *
 768          * Seen elsewhere in example config file:
 769          * A first non-blank "#" character makes the rest of the line
 770          * be ignored. Blank lines are ignored. Lines may be indented freely.
 771          * A "\" character at the very end of the line indicates the next line
 772          * should be treated as a continuation of the current one.
 773          *
 774          * Lines  beginning with "source" are used to include stanzas from
 775          * other files, so configuration can be split into many files.
 776          * The word "source" is followed by the path of file to be sourced.
 777          */
 778 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 779         struct mapping_defn_t *currmap = NULL;
 780 #endif
 781         struct interface_defn_t *currif = NULL;
 782         FILE *f;
 783         char *buf;
 784         char *first_word;
 785         char *rest_of_line;
 786         enum { NONE, IFACE, MAPPING } currently_processing = NONE;
 787
 788         if (!defn)
 789                 defn = xzalloc(sizeof(*defn));
 790
 791         debug_noise("reading %s file:\n", filename);
 792         f = xfopen_for_read(filename);
 793
 794         while ((buf = xmalloc_fgetline(f)) != NULL) {
 795 #if ENABLE_DESKTOP
 796                 /* Trailing "\" concatenates lines */
 797                 char *p;
 798                 while ((p = last_char_is(buf, '\\')) != NULL) {
 799                         *p = '\0';
 800                         rest_of_line = xmalloc_fgetline(f);
 801                         if (!rest_of_line)
 802                                 break;
 803                         p = xasprintf("%s%s", buf, rest_of_line);
 804                         free(buf);
 805                         free(rest_of_line);
 806                         buf = p;
 807                 }
 808 #endif
 809                 rest_of_line = buf;
 810                 first_word = next_word(&rest_of_line);
 811                 if (!first_word || *first_word == '#') {
 812                         free(buf);
 813                         continue; /* blank/comment line */
 814                 }
 815
 816                 if (strcmp(first_word, "mapping") == 0) {
 817 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 818                         currmap = xzalloc(sizeof(*currmap));
 819
 820                         while ((first_word = next_word(&rest_of_line)) != NULL) {
 821                                 currmap->match = xrealloc_vector(currmap->match, 4, currmap->n_matches);
 822                                 currmap->match[currmap->n_matches++] = xstrdup(first_word);
 823                         }
 824                         /*currmap->n_mappings = 0;*/
 825                         /*currmap->mapping = NULL;*/
 826                         /*currmap->script = NULL;*/
 827                         {
 828                                 struct mapping_defn_t **where = &defn->mappings;
 829                                 while (*where != NULL) {
 830                                         where = &(*where)->next;
 831                                 }
 832                                 *where = currmap;
 833                                 /*currmap->next = NULL;*/
 834                         }
 835                         debug_noise("Added mapping\n");
 836 #endif
 837                         currently_processing = MAPPING;
 838                 } else if (strcmp(first_word, "iface") == 0) {
 839                         static const struct address_family_t *const addr_fams[] = {
 840 #if ENABLE_FEATURE_IFUPDOWN_IPV4
 841                                 &addr_inet,
 842 #endif
 843 #if ENABLE_FEATURE_IFUPDOWN_IPV6
 844                                 &addr_inet6,
 845 #endif
 846                                 &addr_link,
 847                                 NULL
 848                         };
 849                         char *iface_name;
 850                         char *address_family_name;
 851                         char *method_name;
 852                         llist_t *iface_list;
 853
 854                         currif = xzalloc(sizeof(*currif));
 855                         iface_name = next_word(&rest_of_line);
 856                         address_family_name = next_word(&rest_of_line);
 857                         method_name = next_word(&rest_of_line);
 858
 859                         if (method_name == NULL)
 860                                 bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
 861
 862                         /* ship any trailing whitespace */
 863                         rest_of_line = skip_whitespace(rest_of_line);
 864
 865                         if (rest_of_line[0] != '\0' /* && rest_of_line[0] != '#' */)
 866                                 bb_error_msg_and_die("too many parameters \"%s\"", buf);
 867
 868                         currif->iface = xstrdup(iface_name);
 869
 870                         currif->address_family = get_address_family(addr_fams, address_family_name);
 871                         if (!currif->address_family)
 872                                 bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
 873
 874                         currif->method = get_method(currif->address_family, method_name);
 875                         if (!currif->method)
 876                                 bb_error_msg_and_die("unknown method \"%s\"", method_name);
 877
 878                         for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
 879                                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
 880                                 if ((strcmp(tmp->iface, currif->iface) == 0)
 881                                  && (tmp->address_family == currif->address_family)
 882                                 ) {
 883                                         bb_error_msg_and_die("duplicate interface \"%s\"", tmp->iface);
 884                                 }
 885                         }
 886                         llist_add_to_end(&(defn->ifaces), (char*)currif);
 887
 888                         debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
 889                         currently_processing = IFACE;
 890                 } else if (strcmp(first_word, "auto") == 0) {
 891                         while ((first_word = next_word(&rest_of_line)) != NULL) {
 892
 893                                 /* Check the interface isnt already listed */
 894                                 if (llist_find_str(defn->autointerfaces, first_word)) {
 895                                         bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
 896                                 }
 897
 898                                 /* Add the interface to the list */
 899                                 llist_add_to_end(&(defn->autointerfaces), xstrdup(first_word));
 900                                 debug_noise("\nauto %s\n", first_word);
 901                         }
 902                         currently_processing = NONE;
 903                 } else if (strcmp(first_word, "source") == 0) {
 904                         read_interfaces(next_word(&rest_of_line), defn);
 905                 } else {
 906                         switch (currently_processing) {
 907                         case IFACE:
 908                                 if (rest_of_line[0] == '\0')
 909                                         bb_error_msg_and_die("option with empty value \"%s\"", buf);
 910
 911                                 if (strcmp(first_word, "post-up") == 0)
 912                                         first_word += 5; /* "up" */
 913                                 else if (strcmp(first_word, "pre-down") == 0)
 914                                         first_word += 4; /* "down" */
 915
 916                                 /* If not one of "up", "down",... words... */
 917                                 if (index_in_strings(keywords_up_down, first_word) < 0) {
 918                                         int i;
 919                                         for (i = 0; i < currif->n_options; i++) {
 920                                                 if (strcmp(currif->option[i].name, first_word) == 0)
 921                                                         bb_error_msg_and_die("duplicate option \"%s\"", buf);
 922                                         }
 923                                 }
 924                                 debug_noise("\t%s=%s\n", first_word, rest_of_line);
 925                                 currif->option = xrealloc_vector(currif->option, 4, currif->n_options);
 926                                 currif->option[currif->n_options].name = xstrdup(first_word);
 927                                 currif->option[currif->n_options].value = xstrdup(rest_of_line);
 928                                 currif->n_options++;
 929                                 break;
 930                         case MAPPING:
 931 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 932                                 if (strcmp(first_word, "script") == 0) {
 933                                         if (currmap->script != NULL)
 934                                                 bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
 935                                         currmap->script = xstrdup(next_word(&rest_of_line));
 936                                 } else if (strcmp(first_word, "map") == 0) {
 937                                         currmap->mapping = xrealloc_vector(currmap->mapping, 2, currmap->n_mappings);
 938                                         currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&rest_of_line));
 939                                         currmap->n_mappings++;
 940                                 } else {
 941                                         bb_error_msg_and_die("misplaced option \"%s\"", buf);
 942                                 }
 943 #endif
 944                                 break;
 945                         case NONE:
 946                         default:
 947                                 bb_error_msg_and_die("misplaced option \"%s\"", buf);
 948                         }
 949                 }
 950                 free(buf);
 951         } /* while (fgets) */
 952
 953         if (ferror(f) != 0) {
 954                 /* ferror does NOT set errno! */
 955                 bb_error_msg_and_die("%s: I/O error", filename);
 956         }
 957         fclose(f);
 958         debug_noise("\ndone reading %s\n\n", filename);
 959
 960         return defn;
 961 }
 962
 963 static char *setlocalenv(const char *format, const char *name, const char *value)
 964 {
 965         char *result;
 966         char *dst;
 967         char *src;
 968         char c;
 969
 970         result = xasprintf(format, name, value);
 971
 972         for (dst = src = result; (c = *src) != '=' && c; src++) {
 973                 if (c == '-')
 974                         c = '_';
 975                 if (c >= 'a' && c <= 'z')
 976                         c -= ('a' - 'A');
 977                 if (isalnum(c) || c == '_')
 978                         *dst++ = c;
 979         }
 980         overlapping_strcpy(dst, src);
 981
 982         return result;
 983 }
 984
 985 static void set_environ(struct interface_defn_t *iface, const char *mode, const char *opt)
 986 {
 987         int i;
 988         char **pp;
 989
 990         if (G.my_environ != NULL) {
 991                 for (pp = G.my_environ; *pp; pp++) {
 992                         free(*pp);
 993                 }
 994                 free(G.my_environ);
 995         }
 996
 997         /* note: last element will stay NULL: */
 998         G.my_environ = xzalloc(sizeof(char *) * (iface->n_options + 7));
 999         pp = G.my_environ;
1000
1001         for (i = 0; i < iface->n_options; i++) {
1002                 if (index_in_strings(keywords_up_down, iface->option[i].name) >= 0) {
1003                         continue;
1004                 }
1005                 *pp++ = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
1006         }
1007
1008         *pp++ = setlocalenv("%s=%s", "IFACE", iface->iface);
1009         *pp++ = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
1010         *pp++ = setlocalenv("%s=%s", "METHOD", iface->method->name);
1011         *pp++ = setlocalenv("%s=%s", "MODE", mode);
1012         *pp++ = setlocalenv("%s=%s", "PHASE", opt);
1013         if (G.startup_PATH)
1014                 *pp++ = setlocalenv("%s=%s", "PATH", G.startup_PATH);
1015 }
1016
1017 static int doit(char *str)
1018 {
1019         if (option_mask32 & (OPT_no_act|OPT_verbose)) {
1020                 puts(str);
1021         }
1022         if (!(option_mask32 & OPT_no_act)) {
1023                 pid_t child;
1024                 int status;
1025
1026                 fflush_all();
1027                 child = vfork();
1028                 if (child < 0) /* failure */
1029                         return 0;
1030                 if (child == 0) { /* child */
1031                         execle(G.shell, G.shell, "-c", str, (char *) NULL, G.my_environ);
1032                         _exit(127);
1033                 }
1034                 safe_waitpid(child, &status, 0);
1035                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
1036                         return 0;
1037                 }
1038         }
1039         return 1;
1040 }
1041
1042 static int execute_all(struct interface_defn_t *ifd, const char *opt)
1043 {
1044         int i;
1045         char *buf;
1046         for (i = 0; i < ifd->n_options; i++) {
1047                 if (strcmp(ifd->option[i].name, opt) == 0) {
1048                         if (!doit(ifd->option[i].value)) {
1049                                 return 0;
1050                         }
1051                 }
1052         }
1053
1054         buf = xasprintf("run-parts /etc/network/if-%s.d", opt);
1055         /* heh, we don't bother free'ing it */
1056         return doit(buf);
1057 }
1058
1059 static int check(char *str)
1060 {
1061         return str != NULL;
1062 }
1063
1064 static int iface_up(struct interface_defn_t *iface)
1065 {
1066         if (!iface->method->up(iface, check)) return -1;
1067         set_environ(iface, "start", "pre-up");
1068         if (!execute_all(iface, "pre-up")) return 0;
1069         if (!iface->method->up(iface, doit)) return 0;
1070         set_environ(iface, "start", "post-up");
1071         if (!execute_all(iface, "up")) return 0;
1072         return 1;
1073 }
1074
1075 static int iface_down(struct interface_defn_t *iface)
1076 {
1077         if (!iface->method->down(iface, check)) return -1;
1078         set_environ(iface, "stop", "pre-down");
1079         if (!execute_all(iface, "down")) return 0;
1080         if (!iface->method->down(iface, doit)) return 0;
1081         set_environ(iface, "stop", "post-down");
1082         if (!execute_all(iface, "post-down")) return 0;
1083         return 1;
1084 }
1085
1086 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1087 static int popen2(FILE **in, FILE **out, char *command, char *param)
1088 {
1089         char *argv[3] = { command, param, NULL };
1090         struct fd_pair infd, outfd;
1091         pid_t pid;
1092
1093         xpiped_pair(infd);
1094         xpiped_pair(outfd);
1095
1096         fflush_all();
1097         pid = xvfork();
1098
1099         if (pid == 0) {
1100                 /* Child */
1101                 /* NB: close _first_, then move fds! */
1102                 close(infd.wr);
1103                 close(outfd.rd);
1104                 xmove_fd(infd.rd, 0);
1105                 xmove_fd(outfd.wr, 1);
1106                 BB_EXECVP_or_die(argv);
1107         }
1108         /* parent */
1109         close(infd.rd);
1110         close(outfd.wr);
1111         *in = xfdopen_for_write(infd.wr);
1112         *out = xfdopen_for_read(outfd.rd);
1113         return pid;
1114 }
1115
1116 static char *run_mapping(char *physical, struct mapping_defn_t *map)
1117 {
1118         FILE *in, *out;
1119         int i, status;
1120         pid_t pid;
1121
1122         char *logical = xstrdup(physical);
1123
1124         /* Run the mapping script. Never fails. */
1125         pid = popen2(&in, &out, map->script, physical);
1126
1127         /* Write mappings to stdin of mapping script. */
1128         for (i = 0; i < map->n_mappings; i++) {
1129                 fprintf(in, "%s\n", map->mapping[i]);
1130         }
1131         fclose(in);
1132         safe_waitpid(pid, &status, 0);
1133
1134         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
1135                 /* If the mapping script exited successfully, try to
1136                  * grab a line of output and use that as the name of the
1137                  * logical interface. */
1138                 char *new_logical = xmalloc_fgetline(out);
1139
1140                 if (new_logical) {
1141                         /* If we are able to read a line of output from the script,
1142                          * remove any trailing whitespace and use this value
1143                          * as the name of the logical interface. */
1144                         char *pch = new_logical + strlen(new_logical) - 1;
1145
1146                         while (pch >= new_logical && isspace(*pch))
1147                                 *(pch--) = '\0';
1148
1149                         free(logical);
1150                         logical = new_logical;
1151                 }
1152         }
1153
1154         fclose(out);
1155
1156         return logical;
1157 }
1158 #endif /* FEATURE_IFUPDOWN_MAPPING */
1159
1160 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
1161 {
1162         unsigned iface_len = strlen(iface);
1163         llist_t *search = state_list;
1164
1165         while (search) {
1166                 if ((strncmp(search->data, iface, iface_len) == 0)
1167                  && (search->data[iface_len] == '=')
1168                 ) {
1169                         return search;
1170                 }
1171                 search = search->link;
1172         }
1173         return NULL;
1174 }
1175
1176 /* read the previous state from the state file */
1177 static llist_t *read_iface_state(void)
1178 {
1179         llist_t *state_list = NULL;
1180         FILE *state_fp = fopen_for_read(CONFIG_IFUPDOWN_IFSTATE_PATH);
1181
1182         if (state_fp) {
1183                 char *start, *end_ptr;
1184                 while ((start = xmalloc_fgets(state_fp)) != NULL) {
1185                         /* We should only need to check for a single character */
1186                         end_ptr = start + strcspn(start, " \t\n");
1187                         *end_ptr = '\0';
1188                         llist_add_to(&state_list, start);
1189                 }
1190                 fclose(state_fp);
1191         }
1192         return state_list;
1193 }
1194
1195
1196 int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1197 int ifupdown_main(int argc UNUSED_PARAM, char **argv)
1198 {
1199         int (*cmds)(struct interface_defn_t *);
1200         struct interfaces_file_t *defn;
1201         llist_t *target_list = NULL;
1202         const char *interfaces = "/etc/network/interfaces";
1203         bool any_failures = 0;
1204
1205         INIT_G();
1206
1207         G.startup_PATH = getenv("PATH");
1208         G.shell = xstrdup(get_shell_name());
1209
1210         cmds = iface_down;
1211         if (applet_name[2] == 'u') {
1212                 /* ifup command */
1213                 cmds = iface_up;
1214         }
1215
1216         getopt32(argv, OPTION_STR, &interfaces);
1217         argv += optind;
1218         if (argv[0]) {
1219                 if (DO_ALL) bb_show_usage();
1220         } else {
1221                 if (!DO_ALL) bb_show_usage();
1222         }
1223
1224         defn = read_interfaces(interfaces, NULL);
1225
1226         /* Create a list of interfaces to work on */
1227         if (DO_ALL) {
1228                 target_list = defn->autointerfaces;
1229         } else {
1230                 llist_add_to_end(&target_list, argv[0]);
1231         }
1232
1233         /* Update the interfaces */
1234         while (target_list) {
1235                 llist_t *iface_list;
1236                 struct interface_defn_t *currif;
1237                 char *iface;
1238                 char *liface;
1239                 char *pch;
1240                 bool okay = 0;
1241                 int cmds_ret;
1242
1243                 iface = xstrdup(target_list->data);
1244                 target_list = target_list->link;
1245
1246                 pch = strchr(iface, '=');
1247                 if (pch) {
1248                         *pch = '\0';
1249                         liface = xstrdup(pch + 1);
1250                 } else {
1251                         liface = xstrdup(iface);
1252                 }
1253
1254                 if (!FORCE) {
1255                         llist_t *state_list = read_iface_state();
1256                         const llist_t *iface_state = find_iface_state(state_list, iface);
1257
1258                         if (cmds == iface_up) {
1259                                 /* ifup */
1260                                 if (iface_state) {
1261                                         bb_error_msg("interface %s already configured", iface);
1262                                         goto next;
1263                                 }
1264                         } else {
1265                                 /* ifdown */
1266                                 if (!iface_state) {
1267                                         bb_error_msg("interface %s not configured", iface);
1268                                         goto next;
1269                                 }
1270                         }
1271                         llist_free(state_list, free);
1272                 }
1273
1274 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1275                 if ((cmds == iface_up) && !NO_MAPPINGS) {
1276                         struct mapping_defn_t *currmap;
1277
1278                         for (currmap = defn->mappings; currmap; currmap = currmap->next) {
1279                                 int i;
1280                                 for (i = 0; i < currmap->n_matches; i++) {
1281                                         if (fnmatch(currmap->match[i], liface, 0) != 0)
1282                                                 continue;
1283                                         if (VERBOSE) {
1284                                                 printf("Running mapping script %s on %s\n", currmap->script, liface);
1285                                         }
1286                                         liface = run_mapping(iface, currmap);
1287                                         break;
1288                                 }
1289                         }
1290                 }
1291 #endif
1292
1293                 iface_list = defn->ifaces;
1294                 while (iface_list) {
1295                         currif = (struct interface_defn_t *) iface_list->data;
1296                         if (strcmp(liface, currif->iface) == 0) {
1297                                 char *oldiface = currif->iface;
1298
1299                                 okay = 1;
1300                                 currif->iface = iface;
1301
1302                                 debug_noise("\nConfiguring interface %s (%s)\n", liface, currif->address_family->name);
1303
1304                                 /* Call the cmds function pointer, does either iface_up() or iface_down() */
1305                                 cmds_ret = cmds(currif);
1306                                 if (cmds_ret == -1) {
1307                                         bb_error_msg("don't seem to have all the variables for %s/%s",
1308                                                         liface, currif->address_family->name);
1309                                         any_failures = 1;
1310                                 } else if (cmds_ret == 0) {
1311                                         any_failures = 1;
1312                                 }
1313
1314                                 currif->iface = oldiface;
1315                         }
1316                         iface_list = iface_list->link;
1317                 }
1318                 if (VERBOSE) {
1319                         bb_putchar('\n');
1320                 }
1321
1322                 if (!okay && !FORCE) {
1323                         bb_error_msg("ignoring unknown interface %s", liface);
1324                         any_failures = 1;
1325                 } else if (!NO_ACT) {
1326                         /* update the state file */
1327                         FILE *state_fp;
1328                         llist_t *state;
1329                         llist_t *state_list = read_iface_state();
1330                         llist_t *iface_state = find_iface_state(state_list, iface);
1331
1332                         if (cmds == iface_up && !any_failures) {
1333                                 char *newiface = xasprintf("%s=%s", iface, liface);
1334                                 if (!iface_state) {
1335                                         llist_add_to_end(&state_list, newiface);
1336                                 } else {
1337                                         free(iface_state->data);
1338                                         iface_state->data = newiface;
1339                                 }
1340                         } else {
1341                                 /* Remove an interface from state_list */
1342                                 llist_unlink(&state_list, iface_state);
1343                                 free(llist_pop(&iface_state));
1344                         }
1345
1346                         /* Actually write the new state */
1347                         state_fp = xfopen_for_write(CONFIG_IFUPDOWN_IFSTATE_PATH);
1348                         state = state_list;
1349                         while (state) {
1350                                 if (state->data) {
1351                                         fprintf(state_fp, "%s\n", state->data);
1352                                 }
1353                                 state = state->link;
1354                         }
1355                         fclose(state_fp);
1356                         llist_free(state_list, free);
1357                 }
1358  next:
1359                 free(iface);
1360                 free(liface);
1361         }
1362
1363         return any_failures;
1364 }