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 instead of /etc/network/interfaces"
  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 #include "common_bufsiz.h"
  48 /* After libbb.h, since it needs sys/types.h on some systems */
  49 #include <sys/utsname.h>
  50 #include <fnmatch.h>
  51
  52 #define MAX_OPT_DEPTH 10
  53
  54 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
  55 #define MAX_INTERFACE_LENGTH 10
  56 #endif
  57
  58 #define UDHCPC_CMD_OPTIONS CONFIG_IFUPDOWN_UDHCPC_CMD_OPTIONS
  59
  60 #define debug_noise(args...) /*fprintf(stderr, args)*/
  61
  62 /* Forward declaration */
  63 struct interface_defn_t;
  64
  65 typedef int execfn(char *command);
  66
  67 struct method_t {
  68         const char *name;
  69         int (*up)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
  70         int (*down)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
  71 };
  72
  73 struct address_family_t {
  74         const char *name;
  75         int n_methods;
  76         const struct method_t *method;
  77 };
  78
  79 struct mapping_defn_t {
  80         struct mapping_defn_t *next;
  81
  82         int max_matches;
  83         int n_matches;
  84         char **match;
  85
  86         char *script;
  87
  88         int n_mappings;
  89         char **mapping;
  90 };
  91
  92 struct variable_t {
  93         char *name;
  94         char *value;
  95 };
  96
  97 struct interface_defn_t {
  98         const struct address_family_t *address_family;
  99         const struct method_t *method;
 100
 101         char *iface;
 102         int n_options;
 103         struct variable_t *option;
 104 };
 105
 106 struct interfaces_file_t {
 107         llist_t *autointerfaces;
 108         llist_t *ifaces;
 109         struct mapping_defn_t *mappings;
 110 };
 111
 112
 113 #define OPTION_STR "anvf" IF_FEATURE_IFUPDOWN_MAPPING("m") "i:"
 114 enum {
 115         OPT_do_all      = 0x1,
 116         OPT_no_act      = 0x2,
 117         OPT_verbose     = 0x4,
 118         OPT_force       = 0x8,
 119         OPT_no_mappings = 0x10,
 120 };
 121 #define DO_ALL      (option_mask32 & OPT_do_all)
 122 #define NO_ACT      (option_mask32 & OPT_no_act)
 123 #define VERBOSE     (option_mask32 & OPT_verbose)
 124 #define FORCE       (option_mask32 & OPT_force)
 125 #define NO_MAPPINGS (option_mask32 & OPT_no_mappings)
 126
 127
 128 struct globals {
 129         char **my_environ;
 130         const char *startup_PATH;
 131         char *shell;
 132 } FIX_ALIASING;
 133 #define G (*(struct globals*)bb_common_bufsiz1)
 134 #define INIT_G() do { setup_common_bufsiz(); } while (0)
 135
 136
 137 static const char keywords_up_down[] ALIGN1 =
 138         "up\0"
 139         "down\0"
 140         "pre-up\0"
 141         "post-down\0"
 142 ;
 143
 144
 145 #if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
 146
 147 static void addstr(char **bufp, const char *str, size_t str_length)
 148 {
 149         /* xasprintf trick will be smaller, but we are often
 150          * called with str_length == 1 - don't want to have
 151          * THAT much of malloc/freeing! */
 152         char *buf = *bufp;
 153         int len = (buf ? strlen(buf) : 0);
 154         str_length++;
 155         buf = xrealloc(buf, len + str_length);
 156         /* copies at most str_length-1 chars! */
 157         safe_strncpy(buf + len, str, str_length);
 158         *bufp = buf;
 159 }
 160
 161 static int strncmpz(const char *l, const char *r, size_t llen)
 162 {
 163         int i = strncmp(l, r, llen);
 164
 165         if (i == 0)
 166                 return - (unsigned char)r[llen];
 167         return i;
 168 }
 169
 170 static char *get_var(const char *id, size_t idlen, struct interface_defn_t *ifd)
 171 {
 172         int i;
 173
 174         if (strncmpz(id, "iface", idlen) == 0) {
 175                 // ubuntu's ifup doesn't do this:
 176                 //static char *label_buf;
 177                 //char *result;
 178                 //free(label_buf);
 179                 //label_buf = xstrdup(ifd->iface);
 180                 // Remove virtual iface suffix
 181                 //result = strchrnul(label_buf, ':');
 182                 //*result = '\0';
 183                 //return label_buf;
 184
 185                 return ifd->iface;
 186         }
 187         if (strncmpz(id, "label", idlen) == 0) {
 188                 return ifd->iface;
 189         }
 190         for (i = 0; i < ifd->n_options; i++) {
 191                 if (strncmpz(id, ifd->option[i].name, idlen) == 0) {
 192                         return ifd->option[i].value;
 193                 }
 194         }
 195         return NULL;
 196 }
 197
 198 # if ENABLE_FEATURE_IFUPDOWN_IP
 199 static int count_netmask_bits(const char *dotted_quad)
 200 {
 201 //      int result;
 202 //      unsigned a, b, c, d;
 203 //      /* Found a netmask...  Check if it is dotted quad */
 204 //      if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
 205 //              return -1;
 206 //      if ((a|b|c|d) >> 8)
 207 //              return -1; /* one of numbers is >= 256 */
 208 //      d |= (a << 24) | (b << 16) | (c << 8); /* IP */
 209 //      d = ~d; /* 11110000 -> 00001111 */
 210
 211         /* Shorter version */
 212         int result;
 213         struct in_addr ip;
 214         unsigned d;
 215
 216         if (inet_aton(dotted_quad, &ip) == 0)
 217                 return -1; /* malformed dotted IP */
 218         d = ntohl(ip.s_addr); /* IP in host order */
 219         d = ~d; /* 11110000 -> 00001111 */
 220         if (d & (d+1)) /* check that it is in 00001111 form */
 221                 return -1; /* no it is not */
 222         result = 32;
 223         while (d) {
 224                 d >>= 1;
 225                 result--;
 226         }
 227         return result;
 228 }
 229 # endif
 230
 231 static char *parse(const char *command, struct interface_defn_t *ifd)
 232 {
 233         size_t old_pos[MAX_OPT_DEPTH] = { 0 };
 234         smallint okay[MAX_OPT_DEPTH] = { 1 };
 235         int opt_depth = 1;
 236         char *result = NULL;
 237
 238         while (*command) {
 239                 switch (*command) {
 240                 default:
 241                         addstr(&result, command, 1);
 242                         command++;
 243                         break;
 244                 case '\\':
 245                         if (command[1])
 246                                 command++;
 247                         addstr(&result, command, 1);
 248                         command++;
 249                         break;
 250                 case '[':
 251                         if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
 252                                 old_pos[opt_depth] = result ? strlen(result) : 0;
 253                                 okay[opt_depth] = 1;
 254                                 opt_depth++;
 255                                 command += 2;
 256                         } else {
 257                                 addstr(&result, command, 1);
 258                                 command++;
 259                         }
 260                         break;
 261                 case ']':
 262                         if (command[1] == ']' && opt_depth > 1) {
 263                                 opt_depth--;
 264                                 if (!okay[opt_depth]) {
 265                                         result[old_pos[opt_depth]] = '\0';
 266                                 }
 267                                 command += 2;
 268                         } else {
 269                                 addstr(&result, command, 1);
 270                                 command++;
 271                         }
 272                         break;
 273                 case '%':
 274                         {
 275                                 char *nextpercent;
 276                                 char *varvalue;
 277
 278                                 command++;
 279                                 nextpercent = strchr(command, '%');
 280                                 if (!nextpercent) {
 281                                         /* Unterminated %var% */
 282                                         free(result);
 283                                         return NULL;
 284                                 }
 285
 286                                 varvalue = get_var(command, nextpercent - command, ifd);
 287
 288                                 if (varvalue) {
 289 # if ENABLE_FEATURE_IFUPDOWN_IP
 290                                         /* "hwaddress <class> <address>":
 291                                          * unlike ifconfig, ip doesnt want <class>
 292                                          * (usually "ether" keyword). Skip it. */
 293                                         if (is_prefixed_with(command, "hwaddress")) {
 294                                                 varvalue = skip_whitespace(skip_non_whitespace(varvalue));
 295                                         }
 296 # endif
 297                                         addstr(&result, varvalue, strlen(varvalue));
 298                                 } else {
 299 # if ENABLE_FEATURE_IFUPDOWN_IP
 300                                         /* Sigh...  Add a special case for 'ip' to convert from
 301                                          * dotted quad to bit count style netmasks.  */
 302                                         if (is_prefixed_with(command, "bnmask")) {
 303                                                 unsigned res;
 304                                                 varvalue = get_var("netmask", 7, ifd);
 305                                                 if (varvalue) {
 306                                                         res = count_netmask_bits(varvalue);
 307                                                         if (res > 0) {
 308                                                                 const char *argument = utoa(res);
 309                                                                 addstr(&result, argument, strlen(argument));
 310                                                                 command = nextpercent + 1;
 311                                                                 break;
 312                                                         }
 313                                                 }
 314                                         }
 315 # endif
 316                                         okay[opt_depth - 1] = 0;
 317                                 }
 318
 319                                 command = nextpercent + 1;
 320                         }
 321                         break;
 322                 }
 323         }
 324
 325         if (opt_depth > 1) {
 326                 /* Unbalanced bracket */
 327                 free(result);
 328                 return NULL;
 329         }
 330
 331         if (!okay[0]) {
 332                 /* Undefined variable and we aren't in a bracket */
 333                 free(result);
 334                 return NULL;
 335         }
 336
 337         return result;
 338 }
 339
 340 /* execute() returns 1 for success and 0 for failure */
 341 static int execute(const char *command, struct interface_defn_t *ifd, execfn *exec)
 342 {
 343         char *out;
 344         int ret;
 345
 346         out = parse(command, ifd);
 347         if (!out) {
 348                 /* parse error? */
 349                 return 0;
 350         }
 351         /* out == "": parsed ok but not all needed variables known, skip */
 352         ret = out[0] ? (*exec)(out) : 1;
 353
 354         free(out);
 355         if (ret != 1) {
 356                 return 0;
 357         }
 358         return 1;
 359 }
 360
 361 #endif /* FEATURE_IFUPDOWN_IPV4 || FEATURE_IFUPDOWN_IPV6 */
 362
 363
 364 #if ENABLE_FEATURE_IFUPDOWN_IPV6
 365
 366 static int FAST_FUNC loopback_up6(struct interface_defn_t *ifd, execfn *exec)
 367 {
 368 # if ENABLE_FEATURE_IFUPDOWN_IP
 369         int result;
 370         result = execute("ip addr add ::1 dev %iface%", ifd, exec);
 371         result += execute("ip link set %iface% up", ifd, exec);
 372         return ((result == 2) ? 2 : 0);
 373 # else
 374         return execute("ifconfig %iface% add ::1", ifd, exec);
 375 # endif
 376 }
 377
 378 static int FAST_FUNC loopback_down6(struct interface_defn_t *ifd, execfn *exec)
 379 {
 380 # if ENABLE_FEATURE_IFUPDOWN_IP
 381         return execute("ip link set %iface% down", ifd, exec);
 382 # else
 383         return execute("ifconfig %iface% del ::1", ifd, exec);
 384 # endif
 385 }
 386
 387 static int FAST_FUNC manual_up_down6(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 388 {
 389         return 1;
 390 }
 391
 392 static int FAST_FUNC static_up6(struct interface_defn_t *ifd, execfn *exec)
 393 {
 394         int result;
 395 # if ENABLE_FEATURE_IFUPDOWN_IP
 396         result = execute("ip addr add %address%/%netmask% dev %iface%[[ label %label%]]", ifd, exec);
 397         result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
 398         /* Reportedly, IPv6 needs "dev %iface%", but IPv4 does not: */
 399         result += execute("[[ip route add ::/0 via %gateway% dev %iface%]][[ metric %metric%]]", ifd, exec);
 400 # else
 401         result = execute("ifconfig %iface%[[ media %media%]][[ hw %hwaddress%]][[ mtu %mtu%]] up", ifd, exec);
 402         result += execute("ifconfig %iface% add %address%/%netmask%", ifd, exec);
 403         result += execute("[[route -A inet6 add ::/0 gw %gateway%[[ metric %metric%]]]]", ifd, exec);
 404 # endif
 405         return ((result == 3) ? 3 : 0);
 406 }
 407
 408 static int FAST_FUNC static_down6(struct interface_defn_t *ifd, execfn *exec)
 409 {
 410 # if ENABLE_FEATURE_IFUPDOWN_IP
 411         return execute("ip link set %iface% down", ifd, exec);
 412 # else
 413         return execute("ifconfig %iface% down", ifd, exec);
 414 # endif
 415 }
 416
 417 # if ENABLE_FEATURE_IFUPDOWN_IP
 418 static int FAST_FUNC v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
 419 {
 420         int result;
 421         result = execute("ip tunnel add %iface% mode sit remote "
 422                         "%endpoint%[[ local %local%]][[ ttl %ttl%]]", ifd, exec);
 423         result += execute("ip link set %iface% up", ifd, exec);
 424         result += execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec);
 425         /* Reportedly, IPv6 needs "dev %iface%", but IPv4 does not: */
 426         result += execute("[[ip route add ::/0 via %gateway% dev %iface%]]", ifd, exec);
 427         return ((result == 4) ? 4 : 0);
 428 }
 429
 430 static int FAST_FUNC v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
 431 {
 432         return execute("ip tunnel del %iface%", ifd, exec);
 433 }
 434 # endif
 435
 436 static const struct method_t methods6[] = {
 437 # if ENABLE_FEATURE_IFUPDOWN_IP
 438         { "v4tunnel" , v4tunnel_up     , v4tunnel_down   , },
 439 # endif
 440         { "static"   , static_up6      , static_down6    , },
 441         { "manual"   , manual_up_down6 , manual_up_down6 , },
 442         { "loopback" , loopback_up6    , loopback_down6  , },
 443 };
 444
 445 static const struct address_family_t addr_inet6 = {
 446         "inet6",
 447         ARRAY_SIZE(methods6),
 448         methods6
 449 };
 450
 451 #endif /* FEATURE_IFUPDOWN_IPV6 */
 452
 453
 454 #if ENABLE_FEATURE_IFUPDOWN_IPV4
 455
 456 static int FAST_FUNC loopback_up(struct interface_defn_t *ifd, execfn *exec)
 457 {
 458 # if ENABLE_FEATURE_IFUPDOWN_IP
 459         int result;
 460         result = execute("ip addr add 127.0.0.1/8 dev %iface%", ifd, exec);
 461         result += execute("ip link set %iface% up", ifd, exec);
 462         return ((result == 2) ? 2 : 0);
 463 # else
 464         return execute("ifconfig %iface% 127.0.0.1 up", ifd, exec);
 465 # endif
 466 }
 467
 468 static int FAST_FUNC loopback_down(struct interface_defn_t *ifd, execfn *exec)
 469 {
 470 # if ENABLE_FEATURE_IFUPDOWN_IP
 471         int result;
 472         result = execute("ip addr flush dev %iface%", ifd, exec);
 473         result += execute("ip link set %iface% down", ifd, exec);
 474         return ((result == 2) ? 2 : 0);
 475 # else
 476         return execute("ifconfig %iface% 127.0.0.1 down", ifd, exec);
 477 # endif
 478 }
 479
 480 static int FAST_FUNC static_up(struct interface_defn_t *ifd, execfn *exec)
 481 {
 482         int result;
 483 # if ENABLE_FEATURE_IFUPDOWN_IP
 484         result = execute("ip addr add %address%/%bnmask%[[ broadcast %broadcast%]] "
 485                         "dev %iface%[[ peer %pointopoint%]][[ label %label%]]", ifd, exec);
 486         result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
 487         result += execute("[[ip route add default via %gateway% dev %iface%[[ metric %metric%]]]]", ifd, exec);
 488         return ((result == 3) ? 3 : 0);
 489 # else
 490         /* ifconfig said to set iface up before it processes hw %hwaddress%,
 491          * which then of course fails. Thus we run two separate ifconfig */
 492         result = execute("ifconfig %iface%[[ hw %hwaddress%]][[ media %media%]][[ mtu %mtu%]] up",
 493                                 ifd, exec);
 494         result += execute("ifconfig %iface% %address% netmask %netmask%"
 495                                 "[[ broadcast %broadcast%]][[ pointopoint %pointopoint%]]",
 496                                 ifd, exec);
 497         result += execute("[[route add default gw %gateway%[[ metric %metric%]] %iface%]]", ifd, exec);
 498         return ((result == 3) ? 3 : 0);
 499 # endif
 500 }
 501
 502 static int FAST_FUNC static_down(struct interface_defn_t *ifd, execfn *exec)
 503 {
 504         int result;
 505 # if ENABLE_FEATURE_IFUPDOWN_IP
 506         /* Optional "label LBL" is necessary if interface is an alias (eth0:0),
 507          * otherwise "ip addr flush dev eth0:0" flushes all addresses on eth0.
 508          */
 509         result = execute("ip addr flush dev %iface%[[ label %label%]]", ifd, exec);
 510         result += execute("ip link set %iface% down", ifd, exec);
 511 # else
 512         /* result = execute("[[route del default gw %gateway% %iface%]]", ifd, exec); */
 513         /* Bringing the interface down deletes the routes in itself.
 514            Otherwise this fails if we reference 'gateway' when using this from dhcp_down */
 515         result = 1;
 516         result += execute("ifconfig %iface% down", ifd, exec);
 517 # endif
 518         return ((result == 2) ? 2 : 0);
 519 }
 520
 521 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 522 struct dhcp_client_t {
 523         const char *name;
 524         const char *startcmd;
 525         const char *stopcmd;
 526 };
 527
 528 static const struct dhcp_client_t ext_dhcp_clients[] = {
 529         { "dhcpcd",
 530                 "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %client%]][[ -l %leasetime%]] %iface%",
 531                 "dhcpcd -k %iface%",
 532         },
 533         { "dhclient",
 534                 "dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
 535                 "kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
 536         },
 537         { "pump",
 538                 "pump -i %iface%[[ -h %hostname%]][[ -l %leasehours%]]",
 539                 "pump -i %iface% -k",
 540         },
 541         { "udhcpc",
 542                 "udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -x hostname:%hostname%]][[ -c %client%]]"
 543                                 "[[ -s %script%]][[ %udhcpc_opts%]]",
 544                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
 545         },
 546 };
 547 # endif /* FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
 548
 549 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 550 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 551 {
 552         unsigned i;
 553 #  if ENABLE_FEATURE_IFUPDOWN_IP
 554         /* ip doesn't up iface when it configures it (unlike ifconfig) */
 555         if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
 556                 return 0;
 557 #  else
 558         /* needed if we have hwaddress on dhcp iface */
 559         if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
 560                 return 0;
 561 #  endif
 562         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
 563                 if (executable_exists(ext_dhcp_clients[i].name))
 564                         return execute(ext_dhcp_clients[i].startcmd, ifd, exec);
 565         }
 566         bb_error_msg("no dhcp clients found");
 567         return 0;
 568 }
 569 # elif ENABLE_UDHCPC
 570 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 571 {
 572 #  if ENABLE_FEATURE_IFUPDOWN_IP
 573         /* ip doesn't up iface when it configures it (unlike ifconfig) */
 574         if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
 575                 return 0;
 576 #  else
 577         /* needed if we have hwaddress on dhcp iface */
 578         if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
 579                 return 0;
 580 #  endif
 581         return execute("udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid "
 582                         "-i %iface%[[ -x hostname:%hostname%]][[ -c %client%]][[ -s %script%]][[ %udhcpc_opts%]]",
 583                         ifd, exec);
 584 }
 585 # else
 586 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd UNUSED_PARAM,
 587                 execfn *exec UNUSED_PARAM)
 588 {
 589         return 0; /* no dhcp support */
 590 }
 591 # endif
 592
 593 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 594 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 595 {
 596         int result = 0;
 597         unsigned i;
 598
 599         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
 600                 if (executable_exists(ext_dhcp_clients[i].name)) {
 601                         result = execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
 602                         if (result)
 603                                 break;
 604                 }
 605         }
 606
 607         if (!result)
 608                 bb_error_msg("warning: no dhcp clients found and stopped");
 609
 610         /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
 611            and it may come back up because udhcpc is still shutting down */
 612         usleep(100000);
 613         result += static_down(ifd, exec);
 614         return ((result == 3) ? 3 : 0);
 615 }
 616 # elif ENABLE_UDHCPC
 617 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 618 {
 619         int result;
 620         result = execute(
 621                 "test -f /var/run/udhcpc.%iface%.pid && "
 622                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
 623                 ifd, exec);
 624         /* Also bring the hardware interface down since
 625            killing the dhcp client alone doesn't do it.
 626            This enables consecutive ifup->ifdown->ifup */
 627         /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
 628            and it may come back up because udhcpc is still shutting down */
 629         usleep(100000);
 630         result += static_down(ifd, exec);
 631         return ((result == 3) ? 3 : 0);
 632 }
 633 # else
 634 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd UNUSED_PARAM,
 635                 execfn *exec UNUSED_PARAM)
 636 {
 637         return 0; /* no dhcp support */
 638 }
 639 # endif
 640
 641 static int FAST_FUNC manual_up_down(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 642 {
 643         return 1;
 644 }
 645
 646 static int FAST_FUNC bootp_up(struct interface_defn_t *ifd, execfn *exec)
 647 {
 648         return execute("bootpc[[ --bootfile %bootfile%]] --dev %iface%"
 649                         "[[ --server %server%]][[ --hwaddr %hwaddr%]]"
 650                         " --returniffail --serverbcast", ifd, exec);
 651 }
 652
 653 static int FAST_FUNC ppp_up(struct interface_defn_t *ifd, execfn *exec)
 654 {
 655         return execute("pon[[ %provider%]]", ifd, exec);
 656 }
 657
 658 static int FAST_FUNC ppp_down(struct interface_defn_t *ifd, execfn *exec)
 659 {
 660         return execute("poff[[ %provider%]]", ifd, exec);
 661 }
 662
 663 static int FAST_FUNC wvdial_up(struct interface_defn_t *ifd, execfn *exec)
 664 {
 665         return execute("start-stop-daemon --start -x wvdial "
 666                 "-p /var/run/wvdial.%iface% -b -m --[[ %provider%]]", ifd, exec);
 667 }
 668
 669 static int FAST_FUNC wvdial_down(struct interface_defn_t *ifd, execfn *exec)
 670 {
 671         return execute("start-stop-daemon --stop -x wvdial "
 672                         "-p /var/run/wvdial.%iface% -s 2", ifd, exec);
 673 }
 674
 675 static const struct method_t methods[] = {
 676         { "manual"  , manual_up_down, manual_up_down, },
 677         { "wvdial"  , wvdial_up     , wvdial_down   , },
 678         { "ppp"     , ppp_up        , ppp_down      , },
 679         { "static"  , static_up     , static_down   , },
 680         { "bootp"   , bootp_up      , static_down   , },
 681         { "dhcp"    , dhcp_up       , dhcp_down     , },
 682         { "loopback", loopback_up   , loopback_down , },
 683 };
 684
 685 static const struct address_family_t addr_inet = {
 686         "inet",
 687         ARRAY_SIZE(methods),
 688         methods
 689 };
 690
 691 #endif  /* FEATURE_IFUPDOWN_IPV4 */
 692
 693 static int FAST_FUNC link_up_down(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
 694 {
 695         return 1;
 696 }
 697
 698 static const struct method_t link_methods[] = {
 699         { "none", link_up_down, link_up_down }
 700 };
 701
 702 static const struct address_family_t addr_link = {
 703         "link", ARRAY_SIZE(link_methods), link_methods
 704 };
 705
 706 /* Returns pointer to the next word, or NULL.
 707  * In 1st case, advances *buf to the word after this one.
 708  */
 709 static char *next_word(char **buf)
 710 {
 711         unsigned length;
 712         char *word;
 713
 714         /* Skip over leading whitespace */
 715         word = skip_whitespace(*buf);
 716
 717         /* Stop on EOL */
 718         if (*word == '\0')
 719                 return NULL;
 720
 721         /* Find the length of this word (can't be 0) */
 722         length = strcspn(word, " \t\n");
 723
 724         /* Unless we are already at NUL, store NUL and advance */
 725         if (word[length] != '\0')
 726                 word[length++] = '\0';
 727
 728         *buf = skip_whitespace(word + length);
 729
 730         return word;
 731 }
 732
 733 static const struct address_family_t *get_address_family(const struct address_family_t *const af[], char *name)
 734 {
 735         int i;
 736
 737         if (!name)
 738                 return NULL;
 739
 740         for (i = 0; af[i]; i++) {
 741                 if (strcmp(af[i]->name, name) == 0) {
 742                         return af[i];
 743                 }
 744         }
 745         return NULL;
 746 }
 747
 748 static const struct method_t *get_method(const struct address_family_t *af, char *name)
 749 {
 750         int i;
 751
 752         if (!name)
 753                 return NULL;
 754         /* TODO: use index_in_str_array() */
 755         for (i = 0; i < af->n_methods; i++) {
 756                 if (strcmp(af->method[i].name, name) == 0) {
 757                         return &af->method[i];
 758                 }
 759         }
 760         return NULL;
 761 }
 762
 763 static struct interfaces_file_t *read_interfaces(const char *filename, struct interfaces_file_t *defn)
 764 {
 765         /* Let's try to be compatible.
 766          *
 767          * "man 5 interfaces" says:
 768          * Lines starting with "#" are ignored. Note that end-of-line
 769          * comments are NOT supported, comments must be on a line of their own.
 770          * A line may be extended across multiple lines by making
 771          * the last character a backslash.
 772          *
 773          * Seen elsewhere in example config file:
 774          * A first non-blank "#" character makes the rest of the line
 775          * be ignored. Blank lines are ignored. Lines may be indented freely.
 776          * A "\" character at the very end of the line indicates the next line
 777          * should be treated as a continuation of the current one.
 778          *
 779          * Lines  beginning with "source" are used to include stanzas from
 780          * other files, so configuration can be split into many files.
 781          * The word "source" is followed by the path of file to be sourced.
 782          */
 783 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 784         struct mapping_defn_t *currmap = NULL;
 785 #endif
 786         struct interface_defn_t *currif = NULL;
 787         FILE *f;
 788         char *buf;
 789         char *first_word;
 790         char *rest_of_line;
 791         enum { NONE, IFACE, MAPPING } currently_processing = NONE;
 792
 793         if (!defn)
 794                 defn = xzalloc(sizeof(*defn));
 795
 796         debug_noise("reading %s file:\n", filename);
 797         f = xfopen_for_read(filename);
 798
 799         while ((buf = xmalloc_fgetline(f)) != NULL) {
 800 #if ENABLE_DESKTOP
 801                 /* Trailing "\" concatenates lines */
 802                 char *p;
 803                 while ((p = last_char_is(buf, '\\')) != NULL) {
 804                         *p = '\0';
 805                         rest_of_line = xmalloc_fgetline(f);
 806                         if (!rest_of_line)
 807                                 break;
 808                         p = xasprintf("%s%s", buf, rest_of_line);
 809                         free(buf);
 810                         free(rest_of_line);
 811                         buf = p;
 812                 }
 813 #endif
 814                 rest_of_line = buf;
 815                 first_word = next_word(&rest_of_line);
 816                 if (!first_word || *first_word == '#') {
 817                         free(buf);
 818                         continue; /* blank/comment line */
 819                 }
 820
 821                 if (strcmp(first_word, "mapping") == 0) {
 822 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 823                         currmap = xzalloc(sizeof(*currmap));
 824
 825                         while ((first_word = next_word(&rest_of_line)) != NULL) {
 826                                 currmap->match = xrealloc_vector(currmap->match, 4, currmap->n_matches);
 827                                 currmap->match[currmap->n_matches++] = xstrdup(first_word);
 828                         }
 829                         /*currmap->n_mappings = 0;*/
 830                         /*currmap->mapping = NULL;*/
 831                         /*currmap->script = NULL;*/
 832                         {
 833                                 struct mapping_defn_t **where = &defn->mappings;
 834                                 while (*where != NULL) {
 835                                         where = &(*where)->next;
 836                                 }
 837                                 *where = currmap;
 838                                 /*currmap->next = NULL;*/
 839                         }
 840                         debug_noise("Added mapping\n");
 841 #endif
 842                         currently_processing = MAPPING;
 843                 } else if (strcmp(first_word, "iface") == 0) {
 844                         static const struct address_family_t *const addr_fams[] = {
 845 #if ENABLE_FEATURE_IFUPDOWN_IPV4
 846                                 &addr_inet,
 847 #endif
 848 #if ENABLE_FEATURE_IFUPDOWN_IPV6
 849                                 &addr_inet6,
 850 #endif
 851                                 &addr_link,
 852                                 NULL
 853                         };
 854                         char *iface_name;
 855                         char *address_family_name;
 856                         char *method_name;
 857
 858                         currif = xzalloc(sizeof(*currif));
 859                         iface_name = next_word(&rest_of_line);
 860                         address_family_name = next_word(&rest_of_line);
 861                         method_name = next_word(&rest_of_line);
 862
 863                         if (method_name == NULL)
 864                                 bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
 865
 866                         /* ship any trailing whitespace */
 867                         rest_of_line = skip_whitespace(rest_of_line);
 868
 869                         if (rest_of_line[0] != '\0' /* && rest_of_line[0] != '#' */)
 870                                 bb_error_msg_and_die("too many parameters \"%s\"", buf);
 871
 872                         currif->iface = xstrdup(iface_name);
 873
 874                         currif->address_family = get_address_family(addr_fams, address_family_name);
 875                         if (!currif->address_family)
 876                                 bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
 877
 878                         currif->method = get_method(currif->address_family, method_name);
 879                         if (!currif->method)
 880                                 bb_error_msg_and_die("unknown method \"%s\"", method_name);
 881 #if 0
 882 // Allegedly, Debian allows a duplicate definition:
 883 // iface eth0 inet static
 884 //     address 192.168.0.15
 885 //     netmask 255.255.0.0
 886 //     gateway 192.168.0.1
 887 //
 888 // iface eth0 inet static
 889 //     address 10.0.0.1
 890 //     netmask 255.255.255.0
 891 //
 892 // This adds *two* addresses to eth0 (probably requires use of "ip", not "ifconfig"
 893 //
 894                         llist_t *iface_list;
 895                         for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
 896                                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
 897                                 if ((strcmp(tmp->iface, currif->iface) == 0)
 898                                  && (tmp->address_family == currif->address_family)
 899                                 ) {
 900                                         bb_error_msg_and_die("duplicate interface \"%s\"", tmp->iface);
 901                                 }
 902                         }
 903 #endif
 904                         llist_add_to_end(&(defn->ifaces), (char*)currif);
 905
 906                         debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
 907                         currently_processing = IFACE;
 908                 } else if (strcmp(first_word, "auto") == 0) {
 909                         while ((first_word = next_word(&rest_of_line)) != NULL) {
 910
 911                                 /* Check the interface isnt already listed */
 912                                 if (llist_find_str(defn->autointerfaces, first_word)) {
 913                                         bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
 914                                 }
 915
 916                                 /* Add the interface to the list */
 917                                 llist_add_to_end(&(defn->autointerfaces), xstrdup(first_word));
 918                                 debug_noise("\nauto %s\n", first_word);
 919                         }
 920                         currently_processing = NONE;
 921                 } else if (strcmp(first_word, "source") == 0) {
 922                         read_interfaces(next_word(&rest_of_line), defn);
 923                 } else {
 924                         switch (currently_processing) {
 925                         case IFACE:
 926                                 if (rest_of_line[0] == '\0')
 927                                         bb_error_msg_and_die("option with empty value \"%s\"", buf);
 928
 929                                 if (strcmp(first_word, "post-up") == 0)
 930                                         first_word += 5; /* "up" */
 931                                 else if (strcmp(first_word, "pre-down") == 0)
 932                                         first_word += 4; /* "down" */
 933
 934                                 /* If not one of "up", "down",... words... */
 935                                 if (index_in_strings(keywords_up_down, first_word) < 0) {
 936                                         int i;
 937                                         for (i = 0; i < currif->n_options; i++) {
 938                                                 if (strcmp(currif->option[i].name, first_word) == 0)
 939                                                         bb_error_msg_and_die("duplicate option \"%s\"", buf);
 940                                         }
 941                                 }
 942                                 debug_noise("\t%s=%s\n", first_word, rest_of_line);
 943                                 currif->option = xrealloc_vector(currif->option, 4, currif->n_options);
 944                                 currif->option[currif->n_options].name = xstrdup(first_word);
 945                                 currif->option[currif->n_options].value = xstrdup(rest_of_line);
 946                                 currif->n_options++;
 947                                 break;
 948                         case MAPPING:
 949 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
 950                                 if (strcmp(first_word, "script") == 0) {
 951                                         if (currmap->script != NULL)
 952                                                 bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
 953                                         currmap->script = xstrdup(next_word(&rest_of_line));
 954                                 } else if (strcmp(first_word, "map") == 0) {
 955                                         currmap->mapping = xrealloc_vector(currmap->mapping, 2, currmap->n_mappings);
 956                                         currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&rest_of_line));
 957                                         currmap->n_mappings++;
 958                                 } else {
 959                                         bb_error_msg_and_die("misplaced option \"%s\"", buf);
 960                                 }
 961 #endif
 962                                 break;
 963                         case NONE:
 964                         default:
 965                                 bb_error_msg_and_die("misplaced option \"%s\"", buf);
 966                         }
 967                 }
 968                 free(buf);
 969         } /* while (fgets) */
 970
 971         if (ferror(f) != 0) {
 972                 /* ferror does NOT set errno! */
 973                 bb_error_msg_and_die("%s: I/O error", filename);
 974         }
 975         fclose(f);
 976         debug_noise("\ndone reading %s\n\n", filename);
 977
 978         return defn;
 979 }
 980
 981 static char *setlocalenv(const char *format, const char *name, const char *value)
 982 {
 983         char *result;
 984         char *dst;
 985         char *src;
 986         char c;
 987
 988         result = xasprintf(format, name, value);
 989
 990         for (dst = src = result; (c = *src) != '=' && c; src++) {
 991                 if (c == '-')
 992                         c = '_';
 993                 if (c >= 'a' && c <= 'z')
 994                         c -= ('a' - 'A');
 995                 if (isalnum(c) || c == '_')
 996                         *dst++ = c;
 997         }
 998         overlapping_strcpy(dst, src);
 999
1000         return result;
1001 }
1002
1003 static void set_environ(struct interface_defn_t *iface, const char *mode, const char *opt)
1004 {
1005         int i;
1006         char **pp;
1007
1008         if (G.my_environ != NULL) {
1009                 for (pp = G.my_environ; *pp; pp++) {
1010                         free(*pp);
1011                 }
1012                 free(G.my_environ);
1013         }
1014
1015         /* note: last element will stay NULL: */
1016         G.my_environ = xzalloc(sizeof(char *) * (iface->n_options + 7));
1017         pp = G.my_environ;
1018
1019         for (i = 0; i < iface->n_options; i++) {
1020                 if (index_in_strings(keywords_up_down, iface->option[i].name) >= 0) {
1021                         continue;
1022                 }
1023                 *pp++ = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
1024         }
1025
1026         *pp++ = setlocalenv("%s=%s", "IFACE", iface->iface);
1027         *pp++ = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
1028         *pp++ = setlocalenv("%s=%s", "METHOD", iface->method->name);
1029         *pp++ = setlocalenv("%s=%s", "MODE", mode);
1030         *pp++ = setlocalenv("%s=%s", "PHASE", opt);
1031         if (G.startup_PATH)
1032                 *pp++ = setlocalenv("%s=%s", "PATH", G.startup_PATH);
1033 }
1034
1035 static int doit(char *str)
1036 {
1037         if (option_mask32 & (OPT_no_act|OPT_verbose)) {
1038                 puts(str);
1039         }
1040         if (!(option_mask32 & OPT_no_act)) {
1041                 pid_t child;
1042                 int status;
1043
1044                 fflush_all();
1045                 child = vfork();
1046                 if (child < 0) /* failure */
1047                         return 0;
1048                 if (child == 0) { /* child */
1049                         execle(G.shell, G.shell, "-c", str, (char *) NULL, G.my_environ);
1050                         _exit(127);
1051                 }
1052                 safe_waitpid(child, &status, 0);
1053                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
1054                         return 0;
1055                 }
1056         }
1057         return 1;
1058 }
1059
1060 static int execute_all(struct interface_defn_t *ifd, const char *opt)
1061 {
1062         int i;
1063         char *buf;
1064         for (i = 0; i < ifd->n_options; i++) {
1065                 if (strcmp(ifd->option[i].name, opt) == 0) {
1066                         if (!doit(ifd->option[i].value)) {
1067                                 return 0;
1068                         }
1069                 }
1070         }
1071
1072         /* Tested on Debian Squeeze: "standard" ifup runs this without
1073          * checking that directory exists. If it doesn't, run-parts
1074          * complains, and this message _is_ annoyingly visible.
1075          * Don't "fix" this (unless newer Debian does).
1076          */
1077         buf = xasprintf("run-parts /etc/network/if-%s.d", opt);
1078         /* heh, we don't bother free'ing it */
1079         return doit(buf);
1080 }
1081
1082 static int check(char *str)
1083 {
1084         return str != NULL;
1085 }
1086
1087 static int iface_up(struct interface_defn_t *iface)
1088 {
1089         if (!iface->method->up(iface, check)) return -1;
1090         set_environ(iface, "start", "pre-up");
1091         if (!execute_all(iface, "pre-up")) return 0;
1092         if (!iface->method->up(iface, doit)) return 0;
1093         set_environ(iface, "start", "post-up");
1094         if (!execute_all(iface, "up")) return 0;
1095         return 1;
1096 }
1097
1098 static int iface_down(struct interface_defn_t *iface)
1099 {
1100         if (!iface->method->down(iface, check)) return -1;
1101         set_environ(iface, "stop", "pre-down");
1102         if (!execute_all(iface, "down")) return 0;
1103         if (!iface->method->down(iface, doit)) return 0;
1104         set_environ(iface, "stop", "post-down");
1105         if (!execute_all(iface, "post-down")) return 0;
1106         return 1;
1107 }
1108
1109 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1110 static int popen2(FILE **in, FILE **out, char *command, char *param)
1111 {
1112         char *argv[3] = { command, param, NULL };
1113         struct fd_pair infd, outfd;
1114         pid_t pid;
1115
1116         xpiped_pair(infd);
1117         xpiped_pair(outfd);
1118
1119         fflush_all();
1120         pid = xvfork();
1121
1122         if (pid == 0) {
1123                 /* Child */
1124                 /* NB: close _first_, then move fds! */
1125                 close(infd.wr);
1126                 close(outfd.rd);
1127                 xmove_fd(infd.rd, 0);
1128                 xmove_fd(outfd.wr, 1);
1129                 BB_EXECVP_or_die(argv);
1130         }
1131         /* parent */
1132         close(infd.rd);
1133         close(outfd.wr);
1134         *in = xfdopen_for_write(infd.wr);
1135         *out = xfdopen_for_read(outfd.rd);
1136         return pid;
1137 }
1138
1139 static char *run_mapping(char *physical, struct mapping_defn_t *map)
1140 {
1141         FILE *in, *out;
1142         int i, status;
1143         pid_t pid;
1144
1145         char *logical = xstrdup(physical);
1146
1147         /* Run the mapping script. Never fails. */
1148         pid = popen2(&in, &out, map->script, physical);
1149
1150         /* Write mappings to stdin of mapping script. */
1151         for (i = 0; i < map->n_mappings; i++) {
1152                 fprintf(in, "%s\n", map->mapping[i]);
1153         }
1154         fclose(in);
1155         safe_waitpid(pid, &status, 0);
1156
1157         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
1158                 /* If the mapping script exited successfully, try to
1159                  * grab a line of output and use that as the name of the
1160                  * logical interface. */
1161                 char *new_logical = xmalloc_fgetline(out);
1162
1163                 if (new_logical) {
1164                         /* If we are able to read a line of output from the script,
1165                          * remove any trailing whitespace and use this value
1166                          * as the name of the logical interface. */
1167                         char *pch = new_logical + strlen(new_logical) - 1;
1168
1169                         while (pch >= new_logical && isspace(*pch))
1170                                 *(pch--) = '\0';
1171
1172                         free(logical);
1173                         logical = new_logical;
1174                 }
1175         }
1176
1177         fclose(out);
1178
1179         return logical;
1180 }
1181 #endif /* FEATURE_IFUPDOWN_MAPPING */
1182
1183 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
1184 {
1185         llist_t *search = state_list;
1186
1187         while (search) {
1188                 char *after_iface = is_prefixed_with(search->data, iface);
1189                 if (after_iface
1190                  && *after_iface == '='
1191                 ) {
1192                         return search;
1193                 }
1194                 search = search->link;
1195         }
1196         return NULL;
1197 }
1198
1199 /* read the previous state from the state file */
1200 static llist_t *read_iface_state(void)
1201 {
1202         llist_t *state_list = NULL;
1203         FILE *state_fp = fopen_for_read(CONFIG_IFUPDOWN_IFSTATE_PATH);
1204
1205         if (state_fp) {
1206                 char *start, *end_ptr;
1207                 while ((start = xmalloc_fgets(state_fp)) != NULL) {
1208                         /* We should only need to check for a single character */
1209                         end_ptr = start + strcspn(start, " \t\n");
1210                         *end_ptr = '\0';
1211                         llist_add_to(&state_list, start);
1212                 }
1213                 fclose(state_fp);
1214         }
1215         return state_list;
1216 }
1217
1218
1219 int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1220 int ifupdown_main(int argc UNUSED_PARAM, char **argv)
1221 {
1222         int (*cmds)(struct interface_defn_t *);
1223         struct interfaces_file_t *defn;
1224         llist_t *target_list = NULL;
1225         const char *interfaces = "/etc/network/interfaces";
1226         bool any_failures = 0;
1227
1228         INIT_G();
1229
1230         G.startup_PATH = getenv("PATH");
1231         G.shell = xstrdup(get_shell_name());
1232
1233         cmds = iface_down;
1234         if (applet_name[2] == 'u') {
1235                 /* ifup command */
1236                 cmds = iface_up;
1237         }
1238
1239         getopt32(argv, OPTION_STR, &interfaces);
1240         argv += optind;
1241         if (argv[0]) {
1242                 if (DO_ALL) bb_show_usage();
1243         } else {
1244                 if (!DO_ALL) bb_show_usage();
1245         }
1246
1247         defn = read_interfaces(interfaces, NULL);
1248
1249         /* Create a list of interfaces to work on */
1250         if (DO_ALL) {
1251                 target_list = defn->autointerfaces;
1252         } else {
1253                 llist_add_to_end(&target_list, argv[0]);
1254         }
1255
1256         /* Update the interfaces */
1257         while (target_list) {
1258                 llist_t *iface_list;
1259                 struct interface_defn_t *currif;
1260                 char *iface;
1261                 char *liface;
1262                 char *pch;
1263                 bool okay = 0;
1264                 int cmds_ret;
1265                 bool curr_failure = 0;
1266
1267                 iface = xstrdup(target_list->data);
1268                 target_list = target_list->link;
1269
1270                 pch = strchr(iface, '=');
1271                 if (pch) {
1272                         *pch = '\0';
1273                         liface = xstrdup(pch + 1);
1274                 } else {
1275                         liface = xstrdup(iface);
1276                 }
1277
1278                 if (!FORCE) {
1279                         llist_t *state_list = read_iface_state();
1280                         const llist_t *iface_state = find_iface_state(state_list, iface);
1281
1282                         if (cmds == iface_up) {
1283                                 /* ifup */
1284                                 if (iface_state) {
1285                                         bb_error_msg("interface %s already configured", iface);
1286                                         goto next;
1287                                 }
1288                         } else {
1289                                 /* ifdown */
1290                                 if (!iface_state) {
1291                                         bb_error_msg("interface %s not configured", iface);
1292                                         goto next;
1293                                 }
1294                         }
1295                         llist_free(state_list, free);
1296                 }
1297
1298 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1299                 if ((cmds == iface_up) && !NO_MAPPINGS) {
1300                         struct mapping_defn_t *currmap;
1301
1302                         for (currmap = defn->mappings; currmap; currmap = currmap->next) {
1303                                 int i;
1304                                 for (i = 0; i < currmap->n_matches; i++) {
1305                                         if (fnmatch(currmap->match[i], liface, 0) != 0)
1306                                                 continue;
1307                                         if (VERBOSE) {
1308                                                 printf("Running mapping script %s on %s\n", currmap->script, liface);
1309                                         }
1310                                         liface = run_mapping(iface, currmap);
1311                                         break;
1312                                 }
1313                         }
1314                 }
1315 #endif
1316
1317                 iface_list = defn->ifaces;
1318                 while (iface_list) {
1319                         currif = (struct interface_defn_t *) iface_list->data;
1320                         if (strcmp(liface, currif->iface) == 0) {
1321                                 char *oldiface = currif->iface;
1322
1323                                 okay = 1;
1324                                 currif->iface = iface;
1325
1326                                 debug_noise("\nConfiguring interface %s (%s)\n", liface, currif->address_family->name);
1327
1328                                 /* Call the cmds function pointer, does either iface_up() or iface_down() */
1329                                 cmds_ret = cmds(currif);
1330                                 if (cmds_ret == -1) {
1331                                         bb_error_msg("don't have all variables for %s/%s",
1332                                                         liface, currif->address_family->name);
1333                                         any_failures = curr_failure = 1;
1334                                 } else if (cmds_ret == 0) {
1335                                         any_failures = curr_failure = 1;
1336                                 }
1337
1338                                 currif->iface = oldiface;
1339                         }
1340                         iface_list = iface_list->link;
1341                 }
1342                 if (VERBOSE) {
1343                         bb_putchar('\n');
1344                 }
1345
1346                 if (!okay && !FORCE) {
1347                         bb_error_msg("ignoring unknown interface %s", liface);
1348                         any_failures = 1;
1349                 } else if (!NO_ACT) {
1350                         /* update the state file */
1351                         FILE *state_fp;
1352                         llist_t *state;
1353                         llist_t *state_list = read_iface_state();
1354                         llist_t *iface_state = find_iface_state(state_list, iface);
1355
1356                         if (cmds == iface_up && !curr_failure) {
1357                                 char *newiface = xasprintf("%s=%s", iface, liface);
1358                                 if (!iface_state) {
1359                                         llist_add_to_end(&state_list, newiface);
1360                                 } else {
1361                                         free(iface_state->data);
1362                                         iface_state->data = newiface;
1363                                 }
1364                         } else {
1365                                 /* Remove an interface from state_list */
1366                                 llist_unlink(&state_list, iface_state);
1367                                 free(llist_pop(&iface_state));
1368                         }
1369
1370                         /* Actually write the new state */
1371                         state_fp = xfopen_for_write(CONFIG_IFUPDOWN_IFSTATE_PATH);
1372                         state = state_list;
1373                         while (state) {
1374                                 if (state->data) {
1375                                         fprintf(state_fp, "%s\n", state->data);
1376                                 }
1377                                 state = state->link;
1378                         }
1379                         fclose(state_fp);
1380                         llist_free(state_list, free);
1381                 }
1382  next:
1383                 free(iface);
1384                 free(liface);
1385         }
1386
1387         return any_failures;
1388 }