whitespace cleanup. no code changes
[platform/upstream/busybox.git] / 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
689 /* Returns pointer to the next word, or NULL.
690  * In 1st case, advances *buf to the word after this one.
691  */
692 static char *next_word(char **buf)
693 {
694         unsigned length;
695         char *word;
696
697         /* Skip over leading whitespace */
698         word = skip_whitespace(*buf);
699
700         /* Stop on EOL */
701         if (*word == '\0')
702                 return NULL;
703
704         /* Find the length of this word (can't be 0) */
705         length = strcspn(word, " \t\n");
706
707         /* Unless we are already at NUL, store NUL and advance */
708         if (word[length] != '\0')
709                 word[length++] = '\0';
710
711         *buf = skip_whitespace(word + length);
712
713         return word;
714 }
715
716 static const struct address_family_t *get_address_family(const struct address_family_t *const af[], char *name)
717 {
718         int i;
719
720         if (!name)
721                 return NULL;
722
723         for (i = 0; af[i]; i++) {
724                 if (strcmp(af[i]->name, name) == 0) {
725                         return af[i];
726                 }
727         }
728         return NULL;
729 }
730
731 static const struct method_t *get_method(const struct address_family_t *af, char *name)
732 {
733         int i;
734
735         if (!name)
736                 return NULL;
737         /* TODO: use index_in_str_array() */
738         for (i = 0; i < af->n_methods; i++) {
739                 if (strcmp(af->method[i].name, name) == 0) {
740                         return &af->method[i];
741                 }
742         }
743         return NULL;
744 }
745
746 static struct interfaces_file_t *read_interfaces(const char *filename)
747 {
748         /* Let's try to be compatible.
749          *
750          * "man 5 interfaces" says:
751          * Lines starting with "#" are ignored. Note that end-of-line
752          * comments are NOT supported, comments must be on a line of their own.
753          * A line may be extended across multiple lines by making
754          * the last character a backslash.
755          *
756          * Seen elsewhere in example config file:
757          * A first non-blank "#" character makes the rest of the line
758          * be ignored. Blank lines are ignored. Lines may be indented freely.
759          * A "\" character at the very end of the line indicates the next line
760          * should be treated as a continuation of the current one.
761          */
762 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
763         struct mapping_defn_t *currmap = NULL;
764 #endif
765         struct interface_defn_t *currif = NULL;
766         struct interfaces_file_t *defn;
767         FILE *f;
768         char *buf;
769         char *first_word;
770         char *rest_of_line;
771         enum { NONE, IFACE, MAPPING } currently_processing = NONE;
772
773         defn = xzalloc(sizeof(*defn));
774         f = xfopen_for_read(filename);
775
776         while ((buf = xmalloc_fgetline(f)) != NULL) {
777 #if ENABLE_DESKTOP
778                 /* Trailing "\" concatenates lines */
779                 char *p;
780                 while ((p = last_char_is(buf, '\\')) != NULL) {
781                         *p = '\0';
782                         rest_of_line = xmalloc_fgetline(f);
783                         if (!rest_of_line)
784                                 break;
785                         p = xasprintf("%s%s", buf, rest_of_line);
786                         free(buf);
787                         free(rest_of_line);
788                         buf = p;
789                 }
790 #endif
791                 rest_of_line = buf;
792                 first_word = next_word(&rest_of_line);
793                 if (!first_word || *first_word == '#') {
794                         free(buf);
795                         continue; /* blank/comment line */
796                 }
797
798                 if (strcmp(first_word, "mapping") == 0) {
799 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
800                         currmap = xzalloc(sizeof(*currmap));
801
802                         while ((first_word = next_word(&rest_of_line)) != NULL) {
803                                 currmap->match = xrealloc_vector(currmap->match, 4, currmap->n_matches);
804                                 currmap->match[currmap->n_matches++] = xstrdup(first_word);
805                         }
806                         /*currmap->n_mappings = 0;*/
807                         /*currmap->mapping = NULL;*/
808                         /*currmap->script = NULL;*/
809                         {
810                                 struct mapping_defn_t **where = &defn->mappings;
811                                 while (*where != NULL) {
812                                         where = &(*where)->next;
813                                 }
814                                 *where = currmap;
815                                 /*currmap->next = NULL;*/
816                         }
817                         debug_noise("Added mapping\n");
818 #endif
819                         currently_processing = MAPPING;
820                 } else if (strcmp(first_word, "iface") == 0) {
821                         static const struct address_family_t *const addr_fams[] = {
822 #if ENABLE_FEATURE_IFUPDOWN_IPV4
823                                 &addr_inet,
824 #endif
825 #if ENABLE_FEATURE_IFUPDOWN_IPV6
826                                 &addr_inet6,
827 #endif
828                                 NULL
829                         };
830                         char *iface_name;
831                         char *address_family_name;
832                         char *method_name;
833                         llist_t *iface_list;
834
835                         currif = xzalloc(sizeof(*currif));
836                         iface_name = next_word(&rest_of_line);
837                         address_family_name = next_word(&rest_of_line);
838                         method_name = next_word(&rest_of_line);
839
840                         if (method_name == NULL)
841                                 bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
842
843                         /* ship any trailing whitespace */
844                         rest_of_line = skip_whitespace(rest_of_line);
845
846                         if (rest_of_line[0] != '\0' /* && rest_of_line[0] != '#' */)
847                                 bb_error_msg_and_die("too many parameters \"%s\"", buf);
848
849                         currif->iface = xstrdup(iface_name);
850
851                         currif->address_family = get_address_family(addr_fams, address_family_name);
852                         if (!currif->address_family)
853                                 bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
854
855                         currif->method = get_method(currif->address_family, method_name);
856                         if (!currif->method)
857                                 bb_error_msg_and_die("unknown method \"%s\"", method_name);
858
859                         for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
860                                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
861                                 if ((strcmp(tmp->iface, currif->iface) == 0)
862                                  && (tmp->address_family == currif->address_family)
863                                 ) {
864                                         bb_error_msg_and_die("duplicate interface \"%s\"", tmp->iface);
865                                 }
866                         }
867                         llist_add_to_end(&(defn->ifaces), (char*)currif);
868
869                         debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
870                         currently_processing = IFACE;
871                 } else if (strcmp(first_word, "auto") == 0) {
872                         while ((first_word = next_word(&rest_of_line)) != NULL) {
873
874                                 /* Check the interface isnt already listed */
875                                 if (llist_find_str(defn->autointerfaces, first_word)) {
876                                         bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
877                                 }
878
879                                 /* Add the interface to the list */
880                                 llist_add_to_end(&(defn->autointerfaces), xstrdup(first_word));
881                                 debug_noise("\nauto %s\n", first_word);
882                         }
883                         currently_processing = NONE;
884                 } else {
885                         switch (currently_processing) {
886                         case IFACE:
887                                 if (rest_of_line[0] == '\0')
888                                         bb_error_msg_and_die("option with empty value \"%s\"", buf);
889
890                                 if (strcmp(first_word, "post-up") == 0)
891                                         first_word += 5; /* "up" */
892                                 else if (strcmp(first_word, "pre-down") == 0)
893                                         first_word += 4; /* "down" */
894
895                                 /* If not one of "up", "down",... words... */
896                                 if (index_in_strings(keywords_up_down, first_word) < 0) {
897                                         int i;
898                                         for (i = 0; i < currif->n_options; i++) {
899                                                 if (strcmp(currif->option[i].name, first_word) == 0)
900                                                         bb_error_msg_and_die("duplicate option \"%s\"", buf);
901                                         }
902                                 }
903                                 debug_noise("\t%s=%s\n", first_word, rest_of_line);
904                                 currif->option = xrealloc_vector(currif->option, 4, currif->n_options);
905                                 currif->option[currif->n_options].name = xstrdup(first_word);
906                                 currif->option[currif->n_options].value = xstrdup(rest_of_line);
907                                 currif->n_options++;
908                                 break;
909                         case MAPPING:
910 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
911                                 if (strcmp(first_word, "script") == 0) {
912                                         if (currmap->script != NULL)
913                                                 bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
914                                         currmap->script = xstrdup(next_word(&rest_of_line));
915                                 } else if (strcmp(first_word, "map") == 0) {
916                                         currmap->mapping = xrealloc_vector(currmap->mapping, 2, currmap->n_mappings);
917                                         currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&rest_of_line));
918                                         currmap->n_mappings++;
919                                 } else {
920                                         bb_error_msg_and_die("misplaced option \"%s\"", buf);
921                                 }
922 #endif
923                                 break;
924                         case NONE:
925                         default:
926                                 bb_error_msg_and_die("misplaced option \"%s\"", buf);
927                         }
928                 }
929                 free(buf);
930         } /* while (fgets) */
931
932         if (ferror(f) != 0) {
933                 /* ferror does NOT set errno! */
934                 bb_error_msg_and_die("%s: I/O error", filename);
935         }
936         fclose(f);
937
938         return defn;
939 }
940
941 static char *setlocalenv(const char *format, const char *name, const char *value)
942 {
943         char *result;
944         char *dst;
945         char *src;
946         char c;
947
948         result = xasprintf(format, name, value);
949
950         for (dst = src = result; (c = *src) != '=' && c; src++) {
951                 if (c == '-')
952                         c = '_';
953                 if (c >= 'a' && c <= 'z')
954                         c -= ('a' - 'A');
955                 if (isalnum(c) || c == '_')
956                         *dst++ = c;
957         }
958         overlapping_strcpy(dst, src);
959
960         return result;
961 }
962
963 static void set_environ(struct interface_defn_t *iface, const char *mode, const char *opt)
964 {
965         int i;
966         char **pp;
967
968         if (G.my_environ != NULL) {
969                 for (pp = G.my_environ; *pp; pp++) {
970                         free(*pp);
971                 }
972                 free(G.my_environ);
973         }
974
975         /* note: last element will stay NULL: */
976         G.my_environ = xzalloc(sizeof(char *) * (iface->n_options + 7));
977         pp = G.my_environ;
978
979         for (i = 0; i < iface->n_options; i++) {
980                 if (index_in_strings(keywords_up_down, iface->option[i].name) >= 0) {
981                         continue;
982                 }
983                 *pp++ = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
984         }
985
986         *pp++ = setlocalenv("%s=%s", "IFACE", iface->iface);
987         *pp++ = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
988         *pp++ = setlocalenv("%s=%s", "METHOD", iface->method->name);
989         *pp++ = setlocalenv("%s=%s", "MODE", mode);
990         *pp++ = setlocalenv("%s=%s", "PHASE", opt);
991         if (G.startup_PATH)
992                 *pp++ = setlocalenv("%s=%s", "PATH", G.startup_PATH);
993 }
994
995 static int doit(char *str)
996 {
997         if (option_mask32 & (OPT_no_act|OPT_verbose)) {
998                 puts(str);
999         }
1000         if (!(option_mask32 & OPT_no_act)) {
1001                 pid_t child;
1002                 int status;
1003
1004                 fflush_all();
1005                 child = vfork();
1006                 if (child < 0) /* failure */
1007                         return 0;
1008                 if (child == 0) { /* child */
1009                         execle(G.shell, G.shell, "-c", str, (char *) NULL, G.my_environ);
1010                         _exit(127);
1011                 }
1012                 safe_waitpid(child, &status, 0);
1013                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
1014                         return 0;
1015                 }
1016         }
1017         return 1;
1018 }
1019
1020 static int execute_all(struct interface_defn_t *ifd, const char *opt)
1021 {
1022         int i;
1023         char *buf;
1024         for (i = 0; i < ifd->n_options; i++) {
1025                 if (strcmp(ifd->option[i].name, opt) == 0) {
1026                         if (!doit(ifd->option[i].value)) {
1027                                 return 0;
1028                         }
1029                 }
1030         }
1031
1032         buf = xasprintf("run-parts /etc/network/if-%s.d", opt);
1033         /* heh, we don't bother free'ing it */
1034         return doit(buf);
1035 }
1036
1037 static int check(char *str)
1038 {
1039         return str != NULL;
1040 }
1041
1042 static int iface_up(struct interface_defn_t *iface)
1043 {
1044         if (!iface->method->up(iface, check)) return -1;
1045         set_environ(iface, "start", "pre-up");
1046         if (!execute_all(iface, "pre-up")) return 0;
1047         if (!iface->method->up(iface, doit)) return 0;
1048         set_environ(iface, "start", "post-up");
1049         if (!execute_all(iface, "up")) return 0;
1050         return 1;
1051 }
1052
1053 static int iface_down(struct interface_defn_t *iface)
1054 {
1055         if (!iface->method->down(iface, check)) return -1;
1056         set_environ(iface, "stop", "pre-down");
1057         if (!execute_all(iface, "down")) return 0;
1058         if (!iface->method->down(iface, doit)) return 0;
1059         set_environ(iface, "stop", "post-down");
1060         if (!execute_all(iface, "post-down")) return 0;
1061         return 1;
1062 }
1063
1064 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1065 static int popen2(FILE **in, FILE **out, char *command, char *param)
1066 {
1067         char *argv[3] = { command, param, NULL };
1068         struct fd_pair infd, outfd;
1069         pid_t pid;
1070
1071         xpiped_pair(infd);
1072         xpiped_pair(outfd);
1073
1074         fflush_all();
1075         pid = xvfork();
1076
1077         if (pid == 0) {
1078                 /* Child */
1079                 /* NB: close _first_, then move fds! */
1080                 close(infd.wr);
1081                 close(outfd.rd);
1082                 xmove_fd(infd.rd, 0);
1083                 xmove_fd(outfd.wr, 1);
1084                 BB_EXECVP_or_die(argv);
1085         }
1086         /* parent */
1087         close(infd.rd);
1088         close(outfd.wr);
1089         *in = xfdopen_for_write(infd.wr);
1090         *out = xfdopen_for_read(outfd.rd);
1091         return pid;
1092 }
1093
1094 static char *run_mapping(char *physical, struct mapping_defn_t *map)
1095 {
1096         FILE *in, *out;
1097         int i, status;
1098         pid_t pid;
1099
1100         char *logical = xstrdup(physical);
1101
1102         /* Run the mapping script. Never fails. */
1103         pid = popen2(&in, &out, map->script, physical);
1104
1105         /* Write mappings to stdin of mapping script. */
1106         for (i = 0; i < map->n_mappings; i++) {
1107                 fprintf(in, "%s\n", map->mapping[i]);
1108         }
1109         fclose(in);
1110         safe_waitpid(pid, &status, 0);
1111
1112         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
1113                 /* If the mapping script exited successfully, try to
1114                  * grab a line of output and use that as the name of the
1115                  * logical interface. */
1116                 char *new_logical = xmalloc_fgetline(out);
1117
1118                 if (new_logical) {
1119                         /* If we are able to read a line of output from the script,
1120                          * remove any trailing whitespace and use this value
1121                          * as the name of the logical interface. */
1122                         char *pch = new_logical + strlen(new_logical) - 1;
1123
1124                         while (pch >= new_logical && isspace(*pch))
1125                                 *(pch--) = '\0';
1126
1127                         free(logical);
1128                         logical = new_logical;
1129                 }
1130         }
1131
1132         fclose(out);
1133
1134         return logical;
1135 }
1136 #endif /* FEATURE_IFUPDOWN_MAPPING */
1137
1138 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
1139 {
1140         unsigned iface_len = strlen(iface);
1141         llist_t *search = state_list;
1142
1143         while (search) {
1144                 if ((strncmp(search->data, iface, iface_len) == 0)
1145                  && (search->data[iface_len] == '=')
1146                 ) {
1147                         return search;
1148                 }
1149                 search = search->link;
1150         }
1151         return NULL;
1152 }
1153
1154 /* read the previous state from the state file */
1155 static llist_t *read_iface_state(void)
1156 {
1157         llist_t *state_list = NULL;
1158         FILE *state_fp = fopen_for_read(CONFIG_IFUPDOWN_IFSTATE_PATH);
1159
1160         if (state_fp) {
1161                 char *start, *end_ptr;
1162                 while ((start = xmalloc_fgets(state_fp)) != NULL) {
1163                         /* We should only need to check for a single character */
1164                         end_ptr = start + strcspn(start, " \t\n");
1165                         *end_ptr = '\0';
1166                         llist_add_to(&state_list, start);
1167                 }
1168                 fclose(state_fp);
1169         }
1170         return state_list;
1171 }
1172
1173
1174 int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1175 int ifupdown_main(int argc UNUSED_PARAM, char **argv)
1176 {
1177         int (*cmds)(struct interface_defn_t *);
1178         struct interfaces_file_t *defn;
1179         llist_t *target_list = NULL;
1180         const char *interfaces = "/etc/network/interfaces";
1181         bool any_failures = 0;
1182
1183         INIT_G();
1184
1185         G.startup_PATH = getenv("PATH");
1186         G.shell = xstrdup(get_shell_name());
1187
1188         cmds = iface_down;
1189         if (applet_name[2] == 'u') {
1190                 /* ifup command */
1191                 cmds = iface_up;
1192         }
1193
1194         getopt32(argv, OPTION_STR, &interfaces);
1195         argv += optind;
1196         if (argv[0]) {
1197                 if (DO_ALL) bb_show_usage();
1198         } else {
1199                 if (!DO_ALL) bb_show_usage();
1200         }
1201
1202         debug_noise("reading %s file:\n", interfaces);
1203         defn = read_interfaces(interfaces);
1204         debug_noise("\ndone reading %s\n\n", interfaces);
1205
1206         /* Create a list of interfaces to work on */
1207         if (DO_ALL) {
1208                 target_list = defn->autointerfaces;
1209         } else {
1210                 llist_add_to_end(&target_list, argv[0]);
1211         }
1212
1213         /* Update the interfaces */
1214         while (target_list) {
1215                 llist_t *iface_list;
1216                 struct interface_defn_t *currif;
1217                 char *iface;
1218                 char *liface;
1219                 char *pch;
1220                 bool okay = 0;
1221                 int cmds_ret;
1222
1223                 iface = xstrdup(target_list->data);
1224                 target_list = target_list->link;
1225
1226                 pch = strchr(iface, '=');
1227                 if (pch) {
1228                         *pch = '\0';
1229                         liface = xstrdup(pch + 1);
1230                 } else {
1231                         liface = xstrdup(iface);
1232                 }
1233
1234                 if (!FORCE) {
1235                         llist_t *state_list = read_iface_state();
1236                         const llist_t *iface_state = find_iface_state(state_list, iface);
1237
1238                         if (cmds == iface_up) {
1239                                 /* ifup */
1240                                 if (iface_state) {
1241                                         bb_error_msg("interface %s already configured", iface);
1242                                         goto next;
1243                                 }
1244                         } else {
1245                                 /* ifdown */
1246                                 if (!iface_state) {
1247                                         bb_error_msg("interface %s not configured", iface);
1248                                         goto next;
1249                                 }
1250                         }
1251                         llist_free(state_list, free);
1252                 }
1253
1254 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1255                 if ((cmds == iface_up) && !NO_MAPPINGS) {
1256                         struct mapping_defn_t *currmap;
1257
1258                         for (currmap = defn->mappings; currmap; currmap = currmap->next) {
1259                                 int i;
1260                                 for (i = 0; i < currmap->n_matches; i++) {
1261                                         if (fnmatch(currmap->match[i], liface, 0) != 0)
1262                                                 continue;
1263                                         if (VERBOSE) {
1264                                                 printf("Running mapping script %s on %s\n", currmap->script, liface);
1265                                         }
1266                                         liface = run_mapping(iface, currmap);
1267                                         break;
1268                                 }
1269                         }
1270                 }
1271 #endif
1272
1273                 iface_list = defn->ifaces;
1274                 while (iface_list) {
1275                         currif = (struct interface_defn_t *) iface_list->data;
1276                         if (strcmp(liface, currif->iface) == 0) {
1277                                 char *oldiface = currif->iface;
1278
1279                                 okay = 1;
1280                                 currif->iface = iface;
1281
1282                                 debug_noise("\nConfiguring interface %s (%s)\n", liface, currif->address_family->name);
1283
1284                                 /* Call the cmds function pointer, does either iface_up() or iface_down() */
1285                                 cmds_ret = cmds(currif);
1286                                 if (cmds_ret == -1) {
1287                                         bb_error_msg("don't seem to have all the variables for %s/%s",
1288                                                         liface, currif->address_family->name);
1289                                         any_failures = 1;
1290                                 } else if (cmds_ret == 0) {
1291                                         any_failures = 1;
1292                                 }
1293
1294                                 currif->iface = oldiface;
1295                         }
1296                         iface_list = iface_list->link;
1297                 }
1298                 if (VERBOSE) {
1299                         bb_putchar('\n');
1300                 }
1301
1302                 if (!okay && !FORCE) {
1303                         bb_error_msg("ignoring unknown interface %s", liface);
1304                         any_failures = 1;
1305                 } else if (!NO_ACT) {
1306                         /* update the state file */
1307                         FILE *state_fp;
1308                         llist_t *state;
1309                         llist_t *state_list = read_iface_state();
1310                         llist_t *iface_state = find_iface_state(state_list, iface);
1311
1312                         if (cmds == iface_up && !any_failures) {
1313                                 char *newiface = xasprintf("%s=%s", iface, liface);
1314                                 if (!iface_state) {
1315                                         llist_add_to_end(&state_list, newiface);
1316                                 } else {
1317                                         free(iface_state->data);
1318                                         iface_state->data = newiface;
1319                                 }
1320                         } else {
1321                                 /* Remove an interface from state_list */
1322                                 llist_unlink(&state_list, iface_state);
1323                                 free(llist_pop(&iface_state));
1324                         }
1325
1326                         /* Actually write the new state */
1327                         state_fp = xfopen_for_write(CONFIG_IFUPDOWN_IFSTATE_PATH);
1328                         state = state_list;
1329                         while (state) {
1330                                 if (state->data) {
1331                                         fprintf(state_fp, "%s\n", state->data);
1332                                 }
1333                                 state = state->link;
1334                         }
1335                         fclose(state_fp);
1336                         llist_free(state_list, free);
1337                 }
1338  next:
1339                 free(iface);
1340                 free(liface);
1341         }
1342
1343         return any_failures;
1344 }