ftpd: fix MDTM's month value. Closes 5336
[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 #define EUNBALBRACK 10001
53 #define EUNDEFVAR   10002
54 #define EUNBALPER   10000
55
56 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
57 #define MAX_INTERFACE_LENGTH 10
58 #endif
59
60 #define UDHCPC_CMD_OPTIONS CONFIG_IFUPDOWN_UDHCPC_CMD_OPTIONS
61
62 #define debug_noise(args...) /*fprintf(stderr, args)*/
63
64 /* Forward declaration */
65 struct interface_defn_t;
66
67 typedef int execfn(char *command);
68
69 struct method_t {
70         const char *name;
71         int (*up)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
72         int (*down)(struct interface_defn_t *ifd, execfn *e) FAST_FUNC;
73 };
74
75 struct address_family_t {
76         const char *name;
77         int n_methods;
78         const struct method_t *method;
79 };
80
81 struct mapping_defn_t {
82         struct mapping_defn_t *next;
83
84         int max_matches;
85         int n_matches;
86         char **match;
87
88         char *script;
89
90         int n_mappings;
91         char **mapping;
92 };
93
94 struct variable_t {
95         char *name;
96         char *value;
97 };
98
99 struct interface_defn_t {
100         const struct address_family_t *address_family;
101         const struct method_t *method;
102
103         char *iface;
104         int n_options;
105         struct variable_t *option;
106 };
107
108 struct interfaces_file_t {
109         llist_t *autointerfaces;
110         llist_t *ifaces;
111         struct mapping_defn_t *mappings;
112 };
113
114
115 #define OPTION_STR "anvf" IF_FEATURE_IFUPDOWN_MAPPING("m") "i:"
116 enum {
117         OPT_do_all      = 0x1,
118         OPT_no_act      = 0x2,
119         OPT_verbose     = 0x4,
120         OPT_force       = 0x8,
121         OPT_no_mappings = 0x10,
122 };
123 #define DO_ALL      (option_mask32 & OPT_do_all)
124 #define NO_ACT      (option_mask32 & OPT_no_act)
125 #define VERBOSE     (option_mask32 & OPT_verbose)
126 #define FORCE       (option_mask32 & OPT_force)
127 #define NO_MAPPINGS (option_mask32 & OPT_no_mappings)
128
129
130 struct globals {
131         char **my_environ;
132         const char *startup_PATH;
133         char *shell;
134 } FIX_ALIASING;
135 #define G (*(struct globals*)&bb_common_bufsiz1)
136 #define INIT_G() do { } while (0)
137
138
139 static const char keywords_up_down[] ALIGN1 =
140         "up\0"
141         "down\0"
142         "pre-up\0"
143         "post-down\0"
144 ;
145
146
147 #if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
148
149 static void addstr(char **bufp, const char *str, size_t str_length)
150 {
151         /* xasprintf trick will be smaller, but we are often
152          * called with str_length == 1 - don't want to have
153          * THAT much of malloc/freeing! */
154         char *buf = *bufp;
155         int len = (buf ? strlen(buf) : 0);
156         str_length++;
157         buf = xrealloc(buf, len + str_length);
158         /* copies at most str_length-1 chars! */
159         safe_strncpy(buf + len, str, str_length);
160         *bufp = buf;
161 }
162
163 static int strncmpz(const char *l, const char *r, size_t llen)
164 {
165         int i = strncmp(l, r, llen);
166
167         if (i == 0)
168                 return - (unsigned char)r[llen];
169         return i;
170 }
171
172 static char *get_var(const char *id, size_t idlen, struct interface_defn_t *ifd)
173 {
174         int i;
175
176         if (strncmpz(id, "iface", idlen) == 0) {
177                 // ubuntu's ifup doesn't do this:
178                 //static char *label_buf;
179                 //char *result;
180                 //free(label_buf);
181                 //label_buf = xstrdup(ifd->iface);
182                 // Remove virtual iface suffix
183                 //result = strchrnul(label_buf, ':');
184                 //*result = '\0';
185                 //return label_buf;
186
187                 return ifd->iface;
188         }
189         if (strncmpz(id, "label", idlen) == 0) {
190                 return ifd->iface;
191         }
192         for (i = 0; i < ifd->n_options; i++) {
193                 if (strncmpz(id, ifd->option[i].name, idlen) == 0) {
194                         return ifd->option[i].value;
195                 }
196         }
197         return NULL;
198 }
199
200 # if ENABLE_FEATURE_IFUPDOWN_IP
201 static int count_netmask_bits(const char *dotted_quad)
202 {
203 //      int result;
204 //      unsigned a, b, c, d;
205 //      /* Found a netmask...  Check if it is dotted quad */
206 //      if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
207 //              return -1;
208 //      if ((a|b|c|d) >> 8)
209 //              return -1; /* one of numbers is >= 256 */
210 //      d |= (a << 24) | (b << 16) | (c << 8); /* IP */
211 //      d = ~d; /* 11110000 -> 00001111 */
212
213         /* Shorter version */
214         int result;
215         struct in_addr ip;
216         unsigned d;
217
218         if (inet_aton(dotted_quad, &ip) == 0)
219                 return -1; /* malformed dotted IP */
220         d = ntohl(ip.s_addr); /* IP in host order */
221         d = ~d; /* 11110000 -> 00001111 */
222         if (d & (d+1)) /* check that it is in 00001111 form */
223                 return -1; /* no it is not */
224         result = 32;
225         while (d) {
226                 d >>= 1;
227                 result--;
228         }
229         return result;
230 }
231 # endif
232
233 static char *parse(const char *command, struct interface_defn_t *ifd)
234 {
235         size_t old_pos[MAX_OPT_DEPTH] = { 0 };
236         int okay[MAX_OPT_DEPTH] = { 1 };
237         int opt_depth = 1;
238         char *result = NULL;
239
240         while (*command) {
241                 switch (*command) {
242                 default:
243                         addstr(&result, command, 1);
244                         command++;
245                         break;
246                 case '\\':
247                         if (command[1]) {
248                                 addstr(&result, command + 1, 1);
249                                 command += 2;
250                         } else {
251                                 addstr(&result, command, 1);
252                                 command++;
253                         }
254                         break;
255                 case '[':
256                         if (command[1] == '[' && opt_depth < MAX_OPT_DEPTH) {
257                                 old_pos[opt_depth] = result ? strlen(result) : 0;
258                                 okay[opt_depth] = 1;
259                                 opt_depth++;
260                                 command += 2;
261                         } else {
262                                 addstr(&result, "[", 1);
263                                 command++;
264                         }
265                         break;
266                 case ']':
267                         if (command[1] == ']' && opt_depth > 1) {
268                                 opt_depth--;
269                                 if (!okay[opt_depth]) {
270                                         result[old_pos[opt_depth]] = '\0';
271                                 }
272                                 command += 2;
273                         } else {
274                                 addstr(&result, "]", 1);
275                                 command++;
276                         }
277                         break;
278                 case '%':
279                         {
280                                 char *nextpercent;
281                                 char *varvalue;
282
283                                 command++;
284                                 nextpercent = strchr(command, '%');
285                                 if (!nextpercent) {
286                                         errno = EUNBALPER;
287                                         free(result);
288                                         return NULL;
289                                 }
290
291                                 varvalue = get_var(command, nextpercent - command, ifd);
292
293                                 if (varvalue) {
294 # if ENABLE_FEATURE_IFUPDOWN_IP
295                                         /* "hwaddress <class> <address>":
296                                          * unlike ifconfig, ip doesnt want <class>
297                                          * (usually "ether" keyword). Skip it. */
298                                         if (strncmp(command, "hwaddress", 9) == 0) {
299                                                 varvalue = skip_whitespace(skip_non_whitespace(varvalue));
300                                         }
301 # endif
302                                         addstr(&result, varvalue, strlen(varvalue));
303                                 } else {
304 # if ENABLE_FEATURE_IFUPDOWN_IP
305                                         /* Sigh...  Add a special case for 'ip' to convert from
306                                          * dotted quad to bit count style netmasks.  */
307                                         if (strncmp(command, "bnmask", 6) == 0) {
308                                                 unsigned res;
309                                                 varvalue = get_var("netmask", 7, ifd);
310                                                 if (varvalue) {
311                                                         res = count_netmask_bits(varvalue);
312                                                         if (res > 0) {
313                                                                 const char *argument = utoa(res);
314                                                                 addstr(&result, argument, strlen(argument));
315                                                                 command = nextpercent + 1;
316                                                                 break;
317                                                         }
318                                                 }
319                                         }
320 # endif
321                                         okay[opt_depth - 1] = 0;
322                                 }
323
324                                 command = nextpercent + 1;
325                         }
326                         break;
327                 }
328         }
329
330         if (opt_depth > 1) {
331                 errno = EUNBALBRACK;
332                 free(result);
333                 return NULL;
334         }
335
336         if (!okay[0]) {
337                 errno = EUNDEFVAR;
338                 free(result);
339                 return NULL;
340         }
341
342         return result;
343 }
344
345 /* execute() returns 1 for success and 0 for failure */
346 static int execute(const char *command, struct interface_defn_t *ifd, execfn *exec)
347 {
348         char *out;
349         int ret;
350
351         out = parse(command, ifd);
352         if (!out) {
353                 /* parse error? */
354                 return 0;
355         }
356         /* out == "": parsed ok but not all needed variables known, skip */
357         ret = out[0] ? (*exec)(out) : 1;
358
359         free(out);
360         if (ret != 1) {
361                 return 0;
362         }
363         return 1;
364 }
365
366 #endif /* FEATURE_IFUPDOWN_IPV4 || FEATURE_IFUPDOWN_IPV6 */
367
368
369 #if ENABLE_FEATURE_IFUPDOWN_IPV6
370
371 static int FAST_FUNC loopback_up6(struct interface_defn_t *ifd, execfn *exec)
372 {
373 # if ENABLE_FEATURE_IFUPDOWN_IP
374         int result;
375         result = execute("ip addr add ::1 dev %iface%", ifd, exec);
376         result += execute("ip link set %iface% up", ifd, exec);
377         return ((result == 2) ? 2 : 0);
378 # else
379         return execute("ifconfig %iface% add ::1", ifd, exec);
380 # endif
381 }
382
383 static int FAST_FUNC loopback_down6(struct interface_defn_t *ifd, execfn *exec)
384 {
385 # if ENABLE_FEATURE_IFUPDOWN_IP
386         return execute("ip link set %iface% down", ifd, exec);
387 # else
388         return execute("ifconfig %iface% del ::1", ifd, exec);
389 # endif
390 }
391
392 static int FAST_FUNC manual_up_down6(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
393 {
394         return 1;
395 }
396
397 static int FAST_FUNC static_up6(struct interface_defn_t *ifd, execfn *exec)
398 {
399         int result;
400 # if ENABLE_FEATURE_IFUPDOWN_IP
401         result = execute("ip addr add %address%/%netmask% dev %iface%[[ label %label%]]", ifd, exec);
402         result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
403         /* Was: "[[ ip ....%gateway% ]]". Removed extra spaces w/o checking */
404         result += execute("[[ip route add ::/0 via %gateway%]][[ prio %metric%]]", ifd, exec);
405 # else
406         result = execute("ifconfig %iface%[[ media %media%]][[ hw %hwaddress%]][[ mtu %mtu%]] up", ifd, exec);
407         result += execute("ifconfig %iface% add %address%/%netmask%", ifd, exec);
408         result += execute("[[route -A inet6 add ::/0 gw %gateway%[[ metric %metric%]]]]", ifd, exec);
409 # endif
410         return ((result == 3) ? 3 : 0);
411 }
412
413 static int FAST_FUNC static_down6(struct interface_defn_t *ifd, execfn *exec)
414 {
415 # if ENABLE_FEATURE_IFUPDOWN_IP
416         return execute("ip link set %iface% down", ifd, exec);
417 # else
418         return execute("ifconfig %iface% down", ifd, exec);
419 # endif
420 }
421
422 # if ENABLE_FEATURE_IFUPDOWN_IP
423 static int FAST_FUNC v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
424 {
425         int result;
426         result = execute("ip tunnel add %iface% mode sit remote "
427                         "%endpoint%[[ local %local%]][[ ttl %ttl%]]", ifd, exec);
428         result += execute("ip link set %iface% up", ifd, exec);
429         result += execute("ip addr add %address%/%netmask% dev %iface%", ifd, exec);
430         result += execute("[[ip route add ::/0 via %gateway%]]", ifd, exec);
431         return ((result == 4) ? 4 : 0);
432 }
433
434 static int FAST_FUNC v4tunnel_down(struct interface_defn_t * ifd, execfn * exec)
435 {
436         return execute("ip tunnel del %iface%", ifd, exec);
437 }
438 # endif
439
440 static const struct method_t methods6[] = {
441 # if ENABLE_FEATURE_IFUPDOWN_IP
442         { "v4tunnel" , v4tunnel_up     , v4tunnel_down   , },
443 # endif
444         { "static"   , static_up6      , static_down6    , },
445         { "manual"   , manual_up_down6 , manual_up_down6 , },
446         { "loopback" , loopback_up6    , loopback_down6  , },
447 };
448
449 static const struct address_family_t addr_inet6 = {
450         "inet6",
451         ARRAY_SIZE(methods6),
452         methods6
453 };
454
455 #endif /* FEATURE_IFUPDOWN_IPV6 */
456
457
458 #if ENABLE_FEATURE_IFUPDOWN_IPV4
459
460 static int FAST_FUNC loopback_up(struct interface_defn_t *ifd, execfn *exec)
461 {
462 # if ENABLE_FEATURE_IFUPDOWN_IP
463         int result;
464         result = execute("ip addr add 127.0.0.1/8 dev %iface%", ifd, exec);
465         result += execute("ip link set %iface% up", ifd, exec);
466         return ((result == 2) ? 2 : 0);
467 # else
468         return execute("ifconfig %iface% 127.0.0.1 up", ifd, exec);
469 # endif
470 }
471
472 static int FAST_FUNC loopback_down(struct interface_defn_t *ifd, execfn *exec)
473 {
474 # if ENABLE_FEATURE_IFUPDOWN_IP
475         int result;
476         result = execute("ip addr flush dev %iface%", ifd, exec);
477         result += execute("ip link set %iface% down", ifd, exec);
478         return ((result == 2) ? 2 : 0);
479 # else
480         return execute("ifconfig %iface% 127.0.0.1 down", ifd, exec);
481 # endif
482 }
483
484 static int FAST_FUNC static_up(struct interface_defn_t *ifd, execfn *exec)
485 {
486         int result;
487 # if ENABLE_FEATURE_IFUPDOWN_IP
488         result = execute("ip addr add %address%/%bnmask%[[ broadcast %broadcast%]] "
489                         "dev %iface%[[ peer %pointopoint%]][[ label %label%]]", ifd, exec);
490         result += execute("ip link set[[ mtu %mtu%]][[ addr %hwaddress%]] %iface% up", ifd, exec);
491         result += execute("[[ip route add default via %gateway% dev %iface%[[ prio %metric%]]]]", ifd, exec);
492         return ((result == 3) ? 3 : 0);
493 # else
494         /* ifconfig said to set iface up before it processes hw %hwaddress%,
495          * which then of course fails. Thus we run two separate ifconfig */
496         result = execute("ifconfig %iface%[[ hw %hwaddress%]][[ media %media%]][[ mtu %mtu%]] up",
497                                 ifd, exec);
498         result += execute("ifconfig %iface% %address% netmask %netmask%"
499                                 "[[ broadcast %broadcast%]][[ pointopoint %pointopoint%]] ",
500                                 ifd, exec);
501         result += execute("[[route add default gw %gateway%[[ metric %metric%]] %iface%]]", ifd, exec);
502         return ((result == 3) ? 3 : 0);
503 # endif
504 }
505
506 static int FAST_FUNC static_down(struct interface_defn_t *ifd, execfn *exec)
507 {
508         int result;
509 # if ENABLE_FEATURE_IFUPDOWN_IP
510         result = execute("ip addr flush dev %iface%", ifd, exec);
511         result += execute("ip link set %iface% down", ifd, exec);
512 # else
513         /* result = execute("[[route del default gw %gateway% %iface%]]", ifd, exec); */
514         /* Bringing the interface down deletes the routes in itself.
515            Otherwise this fails if we reference 'gateway' when using this from dhcp_down */
516         result = 1;
517         result += execute("ifconfig %iface% down", ifd, exec);
518 # endif
519         return ((result == 2) ? 2 : 0);
520 }
521
522 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
523 struct dhcp_client_t {
524         const char *name;
525         const char *startcmd;
526         const char *stopcmd;
527 };
528
529 static const struct dhcp_client_t ext_dhcp_clients[] = {
530         { "dhcpcd",
531                 "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %client%]][[ -l %leasetime%]] %iface%",
532                 "dhcpcd -k %iface%",
533         },
534         { "dhclient",
535                 "dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
536                 "kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
537         },
538         { "pump",
539                 "pump -i %iface%[[ -h %hostname%]][[ -l %leasehours%]]",
540                 "pump -i %iface% -k",
541         },
542         { "udhcpc",
543                 "udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %client%]]"
544                                 "[[ -s %script%]][[ %udhcpc_opts%]]",
545                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
546         },
547 };
548 # endif /* FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
549
550 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
551 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
552 {
553         unsigned i;
554 #  if ENABLE_FEATURE_IFUPDOWN_IP
555         /* ip doesn't up iface when it configures it (unlike ifconfig) */
556         if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
557                 return 0;
558 #  else
559         /* needed if we have hwaddress on dhcp iface */
560         if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
561                 return 0;
562 #  endif
563         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
564                 if (exists_execable(ext_dhcp_clients[i].name))
565                         return execute(ext_dhcp_clients[i].startcmd, ifd, exec);
566         }
567         bb_error_msg("no dhcp clients found");
568         return 0;
569 }
570 # elif ENABLE_UDHCPC
571 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd, execfn *exec)
572 {
573 #  if ENABLE_FEATURE_IFUPDOWN_IP
574         /* ip doesn't up iface when it configures it (unlike ifconfig) */
575         if (!execute("ip link set[[ addr %hwaddress%]] %iface% up", ifd, exec))
576                 return 0;
577 #  else
578         /* needed if we have hwaddress on dhcp iface */
579         if (!execute("ifconfig %iface%[[ hw %hwaddress%]] up", ifd, exec))
580                 return 0;
581 #  endif
582         return execute("udhcpc " UDHCPC_CMD_OPTIONS " -p /var/run/udhcpc.%iface%.pid "
583                         "-i %iface%[[ -H %hostname%]][[ -c %client%]][[ -s %script%]][[ %udhcpc_opts%]]",
584                         ifd, exec);
585 }
586 # else
587 static int FAST_FUNC dhcp_up(struct interface_defn_t *ifd UNUSED_PARAM,
588                 execfn *exec UNUSED_PARAM)
589 {
590         return 0; /* no dhcp support */
591 }
592 # endif
593
594 # if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
595 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
596 {
597         int result = 0;
598         unsigned i;
599
600         for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
601                 if (exists_execable(ext_dhcp_clients[i].name)) {
602                         result = execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
603                         if (result)
604                                 break;
605                 }
606         }
607
608         if (!result)
609                 bb_error_msg("warning: no dhcp clients found and stopped");
610
611         /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
612            and it may come back up because udhcpc is still shutting down */
613         usleep(100000);
614         result += static_down(ifd, exec);
615         return ((result == 3) ? 3 : 0);
616 }
617 # elif ENABLE_UDHCPC
618 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd, execfn *exec)
619 {
620         int result;
621         result = execute(
622                 "test -f /var/run/udhcpc.%iface%.pid && "
623                 "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
624                 ifd, exec);
625         /* Also bring the hardware interface down since
626            killing the dhcp client alone doesn't do it.
627            This enables consecutive ifup->ifdown->ifup */
628         /* Sleep a bit, otherwise static_down tries to bring down interface too soon,
629            and it may come back up because udhcpc is still shutting down */
630         usleep(100000);
631         result += static_down(ifd, exec);
632         return ((result == 3) ? 3 : 0);
633 }
634 # else
635 static int FAST_FUNC dhcp_down(struct interface_defn_t *ifd UNUSED_PARAM,
636                 execfn *exec UNUSED_PARAM)
637 {
638         return 0; /* no dhcp support */
639 }
640 # endif
641
642 static int FAST_FUNC manual_up_down(struct interface_defn_t *ifd UNUSED_PARAM, execfn *exec UNUSED_PARAM)
643 {
644         return 1;
645 }
646
647 static int FAST_FUNC bootp_up(struct interface_defn_t *ifd, execfn *exec)
648 {
649         return execute("bootpc[[ --bootfile %bootfile%]] --dev %iface%"
650                         "[[ --server %server%]][[ --hwaddr %hwaddr%]]"
651                         " --returniffail --serverbcast", ifd, exec);
652 }
653
654 static int FAST_FUNC ppp_up(struct interface_defn_t *ifd, execfn *exec)
655 {
656         return execute("pon[[ %provider%]]", ifd, exec);
657 }
658
659 static int FAST_FUNC ppp_down(struct interface_defn_t *ifd, execfn *exec)
660 {
661         return execute("poff[[ %provider%]]", ifd, exec);
662 }
663
664 static int FAST_FUNC wvdial_up(struct interface_defn_t *ifd, execfn *exec)
665 {
666         return execute("start-stop-daemon --start -x wvdial "
667                 "-p /var/run/wvdial.%iface% -b -m --[[ %provider%]]", ifd, exec);
668 }
669
670 static int FAST_FUNC wvdial_down(struct interface_defn_t *ifd, execfn *exec)
671 {
672         return execute("start-stop-daemon --stop -x wvdial "
673                         "-p /var/run/wvdial.%iface% -s 2", ifd, exec);
674 }
675
676 static const struct method_t methods[] = {
677         { "manual"  , manual_up_down, manual_up_down, },
678         { "wvdial"  , wvdial_up     , wvdial_down   , },
679         { "ppp"     , ppp_up        , ppp_down      , },
680         { "static"  , static_up     , static_down   , },
681         { "bootp"   , bootp_up      , static_down   , },
682         { "dhcp"    , dhcp_up       , dhcp_down     , },
683         { "loopback", loopback_up   , loopback_down , },
684 };
685
686 static const struct address_family_t addr_inet = {
687         "inet",
688         ARRAY_SIZE(methods),
689         methods
690 };
691
692 #endif  /* FEATURE_IFUPDOWN_IPV4 */
693
694
695 /* Returns pointer to the next word, or NULL.
696  * In 1st case, advances *buf to the word after this one.
697  */
698 static char *next_word(char **buf)
699 {
700         unsigned length;
701         char *word;
702
703         /* Skip over leading whitespace */
704         word = skip_whitespace(*buf);
705
706         /* Stop on EOL */
707         if (*word == '\0')
708                 return NULL;
709
710         /* Find the length of this word (can't be 0) */
711         length = strcspn(word, " \t\n");
712
713         /* Unless we are already at NUL, store NUL and advance */
714         if (word[length] != '\0')
715                 word[length++] = '\0';
716
717         *buf = skip_whitespace(word + length);
718
719         return word;
720 }
721
722 static const struct address_family_t *get_address_family(const struct address_family_t *const af[], char *name)
723 {
724         int i;
725
726         if (!name)
727                 return NULL;
728
729         for (i = 0; af[i]; i++) {
730                 if (strcmp(af[i]->name, name) == 0) {
731                         return af[i];
732                 }
733         }
734         return NULL;
735 }
736
737 static const struct method_t *get_method(const struct address_family_t *af, char *name)
738 {
739         int i;
740
741         if (!name)
742                 return NULL;
743         /* TODO: use index_in_str_array() */
744         for (i = 0; i < af->n_methods; i++) {
745                 if (strcmp(af->method[i].name, name) == 0) {
746                         return &af->method[i];
747                 }
748         }
749         return NULL;
750 }
751
752 static struct interfaces_file_t *read_interfaces(const char *filename)
753 {
754         /* Let's try to be compatible.
755          *
756          * "man 5 interfaces" says:
757          * Lines starting with "#" are ignored. Note that end-of-line
758          * comments are NOT supported, comments must be on a line of their own.
759          * A line may be extended across multiple lines by making
760          * the last character a backslash.
761          *
762          * Seen elsewhere in example config file:
763          * A first non-blank "#" character makes the rest of the line
764          * be ignored. Blank lines are ignored. Lines may be indented freely.
765          * A "\" character at the very end of the line indicates the next line
766          * should be treated as a continuation of the current one.
767          */
768 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
769         struct mapping_defn_t *currmap = NULL;
770 #endif
771         struct interface_defn_t *currif = NULL;
772         struct interfaces_file_t *defn;
773         FILE *f;
774         char *buf;
775         char *first_word;
776         char *rest_of_line;
777         enum { NONE, IFACE, MAPPING } currently_processing = NONE;
778
779         defn = xzalloc(sizeof(*defn));
780         f = xfopen_for_read(filename);
781
782         while ((buf = xmalloc_fgetline(f)) != NULL) {
783 #if ENABLE_DESKTOP
784                 /* Trailing "\" concatenates lines */
785                 char *p;
786                 while ((p = last_char_is(buf, '\\')) != NULL) {
787                         *p = '\0';
788                         rest_of_line = xmalloc_fgetline(f);
789                         if (!rest_of_line)
790                                 break;
791                         p = xasprintf("%s%s", buf, rest_of_line);
792                         free(buf);
793                         free(rest_of_line);
794                         buf = p;
795                 }
796 #endif
797                 rest_of_line = buf;
798                 first_word = next_word(&rest_of_line);
799                 if (!first_word || *first_word == '#') {
800                         free(buf);
801                         continue; /* blank/comment line */
802                 }
803
804                 if (strcmp(first_word, "mapping") == 0) {
805 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
806                         currmap = xzalloc(sizeof(*currmap));
807
808                         while ((first_word = next_word(&rest_of_line)) != NULL) {
809                                 currmap->match = xrealloc_vector(currmap->match, 4, currmap->n_matches);
810                                 currmap->match[currmap->n_matches++] = xstrdup(first_word);
811                         }
812                         /*currmap->n_mappings = 0;*/
813                         /*currmap->mapping = NULL;*/
814                         /*currmap->script = NULL;*/
815                         {
816                                 struct mapping_defn_t **where = &defn->mappings;
817                                 while (*where != NULL) {
818                                         where = &(*where)->next;
819                                 }
820                                 *where = currmap;
821                                 /*currmap->next = NULL;*/
822                         }
823                         debug_noise("Added mapping\n");
824 #endif
825                         currently_processing = MAPPING;
826                 } else if (strcmp(first_word, "iface") == 0) {
827                         static const struct address_family_t *const addr_fams[] = {
828 #if ENABLE_FEATURE_IFUPDOWN_IPV4
829                                 &addr_inet,
830 #endif
831 #if ENABLE_FEATURE_IFUPDOWN_IPV6
832                                 &addr_inet6,
833 #endif
834                                 NULL
835                         };
836                         char *iface_name;
837                         char *address_family_name;
838                         char *method_name;
839                         llist_t *iface_list;
840
841                         currif = xzalloc(sizeof(*currif));
842                         iface_name = next_word(&rest_of_line);
843                         address_family_name = next_word(&rest_of_line);
844                         method_name = next_word(&rest_of_line);
845
846                         if (method_name == NULL)
847                                 bb_error_msg_and_die("too few parameters for line \"%s\"", buf);
848
849                         /* ship any trailing whitespace */
850                         rest_of_line = skip_whitespace(rest_of_line);
851
852                         if (rest_of_line[0] != '\0' /* && rest_of_line[0] != '#' */)
853                                 bb_error_msg_and_die("too many parameters \"%s\"", buf);
854
855                         currif->iface = xstrdup(iface_name);
856
857                         currif->address_family = get_address_family(addr_fams, address_family_name);
858                         if (!currif->address_family)
859                                 bb_error_msg_and_die("unknown address type \"%s\"", address_family_name);
860
861                         currif->method = get_method(currif->address_family, method_name);
862                         if (!currif->method)
863                                 bb_error_msg_and_die("unknown method \"%s\"", method_name);
864
865                         for (iface_list = defn->ifaces; iface_list; iface_list = iface_list->link) {
866                                 struct interface_defn_t *tmp = (struct interface_defn_t *) iface_list->data;
867                                 if ((strcmp(tmp->iface, currif->iface) == 0)
868                                  && (tmp->address_family == currif->address_family)
869                                 ) {
870                                         bb_error_msg_and_die("duplicate interface \"%s\"", tmp->iface);
871                                 }
872                         }
873                         llist_add_to_end(&(defn->ifaces), (char*)currif);
874
875                         debug_noise("iface %s %s %s\n", currif->iface, address_family_name, method_name);
876                         currently_processing = IFACE;
877                 } else if (strcmp(first_word, "auto") == 0) {
878                         while ((first_word = next_word(&rest_of_line)) != NULL) {
879
880                                 /* Check the interface isnt already listed */
881                                 if (llist_find_str(defn->autointerfaces, first_word)) {
882                                         bb_perror_msg_and_die("interface declared auto twice \"%s\"", buf);
883                                 }
884
885                                 /* Add the interface to the list */
886                                 llist_add_to_end(&(defn->autointerfaces), xstrdup(first_word));
887                                 debug_noise("\nauto %s\n", first_word);
888                         }
889                         currently_processing = NONE;
890                 } else {
891                         switch (currently_processing) {
892                         case IFACE:
893                                 if (rest_of_line[0] == '\0')
894                                         bb_error_msg_and_die("option with empty value \"%s\"", buf);
895
896                                 if (strcmp(first_word, "post-up") == 0)
897                                         first_word += 5; /* "up" */
898                                 else if (strcmp(first_word, "pre-down") == 0)
899                                         first_word += 4; /* "down" */
900
901                                 /* If not one of "up", "down",... words... */
902                                 if (index_in_strings(keywords_up_down, first_word) < 0) {
903                                         int i;
904                                         for (i = 0; i < currif->n_options; i++) {
905                                                 if (strcmp(currif->option[i].name, first_word) == 0)
906                                                         bb_error_msg_and_die("duplicate option \"%s\"", buf);
907                                         }
908                                 }
909                                 debug_noise("\t%s=%s\n", first_word, rest_of_line);
910                                 currif->option = xrealloc_vector(currif->option, 4, currif->n_options);
911                                 currif->option[currif->n_options].name = xstrdup(first_word);
912                                 currif->option[currif->n_options].value = xstrdup(rest_of_line);
913                                 currif->n_options++;
914                                 break;
915                         case MAPPING:
916 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
917                                 if (strcmp(first_word, "script") == 0) {
918                                         if (currmap->script != NULL)
919                                                 bb_error_msg_and_die("duplicate script in mapping \"%s\"", buf);
920                                         currmap->script = xstrdup(next_word(&rest_of_line));
921                                 } else if (strcmp(first_word, "map") == 0) {
922                                         currmap->mapping = xrealloc_vector(currmap->mapping, 2, currmap->n_mappings);
923                                         currmap->mapping[currmap->n_mappings] = xstrdup(next_word(&rest_of_line));
924                                         currmap->n_mappings++;
925                                 } else {
926                                         bb_error_msg_and_die("misplaced option \"%s\"", buf);
927                                 }
928 #endif
929                                 break;
930                         case NONE:
931                         default:
932                                 bb_error_msg_and_die("misplaced option \"%s\"", buf);
933                         }
934                 }
935                 free(buf);
936         } /* while (fgets) */
937
938         if (ferror(f) != 0) {
939                 /* ferror does NOT set errno! */
940                 bb_error_msg_and_die("%s: I/O error", filename);
941         }
942         fclose(f);
943
944         return defn;
945 }
946
947 static char *setlocalenv(const char *format, const char *name, const char *value)
948 {
949         char *result;
950         char *dst;
951         char *src;
952         char c;
953
954         result = xasprintf(format, name, value);
955
956         for (dst = src = result; (c = *src) != '=' && c; src++) {
957                 if (c == '-')
958                         c = '_';
959                 if (c >= 'a' && c <= 'z')
960                         c -= ('a' - 'A');
961                 if (isalnum(c) || c == '_')
962                         *dst++ = c;
963         }
964         overlapping_strcpy(dst, src);
965
966         return result;
967 }
968
969 static void set_environ(struct interface_defn_t *iface, const char *mode, const char *opt)
970 {
971         int i;
972         char **pp;
973
974         if (G.my_environ != NULL) {
975                 for (pp = G.my_environ; *pp; pp++) {
976                         free(*pp);
977                 }
978                 free(G.my_environ);
979         }
980
981         /* note: last element will stay NULL: */
982         G.my_environ = xzalloc(sizeof(char *) * (iface->n_options + 7));
983         pp = G.my_environ;
984
985         for (i = 0; i < iface->n_options; i++) {
986                 if (index_in_strings(keywords_up_down, iface->option[i].name) >= 0) {
987                         continue;
988                 }
989                 *pp++ = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
990         }
991
992         *pp++ = setlocalenv("%s=%s", "IFACE", iface->iface);
993         *pp++ = setlocalenv("%s=%s", "ADDRFAM", iface->address_family->name);
994         *pp++ = setlocalenv("%s=%s", "METHOD", iface->method->name);
995         *pp++ = setlocalenv("%s=%s", "MODE", mode);
996         *pp++ = setlocalenv("%s=%s", "PHASE", opt);
997         if (G.startup_PATH)
998                 *pp++ = setlocalenv("%s=%s", "PATH", G.startup_PATH);
999 }
1000
1001 static int doit(char *str)
1002 {
1003         if (option_mask32 & (OPT_no_act|OPT_verbose)) {
1004                 puts(str);
1005         }
1006         if (!(option_mask32 & OPT_no_act)) {
1007                 pid_t child;
1008                 int status;
1009
1010                 fflush_all();
1011                 child = vfork();
1012                 if (child < 0) /* failure */
1013                         return 0;
1014                 if (child == 0) { /* child */
1015                         execle(G.shell, G.shell, "-c", str, (char *) NULL, G.my_environ);
1016                         _exit(127);
1017                 }
1018                 safe_waitpid(child, &status, 0);
1019                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
1020                         return 0;
1021                 }
1022         }
1023         return 1;
1024 }
1025
1026 static int execute_all(struct interface_defn_t *ifd, const char *opt)
1027 {
1028         int i;
1029         char *buf;
1030         for (i = 0; i < ifd->n_options; i++) {
1031                 if (strcmp(ifd->option[i].name, opt) == 0) {
1032                         if (!doit(ifd->option[i].value)) {
1033                                 return 0;
1034                         }
1035                 }
1036         }
1037
1038         buf = xasprintf("run-parts /etc/network/if-%s.d", opt);
1039         /* heh, we don't bother free'ing it */
1040         return doit(buf);
1041 }
1042
1043 static int check(char *str)
1044 {
1045         return str != NULL;
1046 }
1047
1048 static int iface_up(struct interface_defn_t *iface)
1049 {
1050         if (!iface->method->up(iface, check)) return -1;
1051         set_environ(iface, "start", "pre-up");
1052         if (!execute_all(iface, "pre-up")) return 0;
1053         if (!iface->method->up(iface, doit)) return 0;
1054         set_environ(iface, "start", "post-up");
1055         if (!execute_all(iface, "up")) return 0;
1056         return 1;
1057 }
1058
1059 static int iface_down(struct interface_defn_t *iface)
1060 {
1061         if (!iface->method->down(iface,check)) return -1;
1062         set_environ(iface, "stop", "pre-down");
1063         if (!execute_all(iface, "down")) return 0;
1064         if (!iface->method->down(iface, doit)) return 0;
1065         set_environ(iface, "stop", "post-down");
1066         if (!execute_all(iface, "post-down")) return 0;
1067         return 1;
1068 }
1069
1070 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1071 static int popen2(FILE **in, FILE **out, char *command, char *param)
1072 {
1073         char *argv[3] = { command, param, NULL };
1074         struct fd_pair infd, outfd;
1075         pid_t pid;
1076
1077         xpiped_pair(infd);
1078         xpiped_pair(outfd);
1079
1080         fflush_all();
1081         pid = xvfork();
1082
1083         if (pid == 0) {
1084                 /* Child */
1085                 /* NB: close _first_, then move fds! */
1086                 close(infd.wr);
1087                 close(outfd.rd);
1088                 xmove_fd(infd.rd, 0);
1089                 xmove_fd(outfd.wr, 1);
1090                 BB_EXECVP_or_die(argv);
1091         }
1092         /* parent */
1093         close(infd.rd);
1094         close(outfd.wr);
1095         *in = xfdopen_for_write(infd.wr);
1096         *out = xfdopen_for_read(outfd.rd);
1097         return pid;
1098 }
1099
1100 static char *run_mapping(char *physical, struct mapping_defn_t *map)
1101 {
1102         FILE *in, *out;
1103         int i, status;
1104         pid_t pid;
1105
1106         char *logical = xstrdup(physical);
1107
1108         /* Run the mapping script. Never fails. */
1109         pid = popen2(&in, &out, map->script, physical);
1110
1111         /* Write mappings to stdin of mapping script. */
1112         for (i = 0; i < map->n_mappings; i++) {
1113                 fprintf(in, "%s\n", map->mapping[i]);
1114         }
1115         fclose(in);
1116         safe_waitpid(pid, &status, 0);
1117
1118         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
1119                 /* If the mapping script exited successfully, try to
1120                  * grab a line of output and use that as the name of the
1121                  * logical interface. */
1122                 char *new_logical = xmalloc_fgetline(out);
1123
1124                 if (new_logical) {
1125                         /* If we are able to read a line of output from the script,
1126                          * remove any trailing whitespace and use this value
1127                          * as the name of the logical interface. */
1128                         char *pch = new_logical + strlen(new_logical) - 1;
1129
1130                         while (pch >= new_logical && isspace(*pch))
1131                                 *(pch--) = '\0';
1132
1133                         free(logical);
1134                         logical = new_logical;
1135                 }
1136         }
1137
1138         fclose(out);
1139
1140         return logical;
1141 }
1142 #endif /* FEATURE_IFUPDOWN_MAPPING */
1143
1144 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
1145 {
1146         unsigned iface_len = strlen(iface);
1147         llist_t *search = state_list;
1148
1149         while (search) {
1150                 if ((strncmp(search->data, iface, iface_len) == 0)
1151                  && (search->data[iface_len] == '=')
1152                 ) {
1153                         return search;
1154                 }
1155                 search = search->link;
1156         }
1157         return NULL;
1158 }
1159
1160 /* read the previous state from the state file */
1161 static llist_t *read_iface_state(void)
1162 {
1163         llist_t *state_list = NULL;
1164         FILE *state_fp = fopen_for_read(CONFIG_IFUPDOWN_IFSTATE_PATH);
1165
1166         if (state_fp) {
1167                 char *start, *end_ptr;
1168                 while ((start = xmalloc_fgets(state_fp)) != NULL) {
1169                         /* We should only need to check for a single character */
1170                         end_ptr = start + strcspn(start, " \t\n");
1171                         *end_ptr = '\0';
1172                         llist_add_to(&state_list, start);
1173                 }
1174                 fclose(state_fp);
1175         }
1176         return state_list;
1177 }
1178
1179
1180 int ifupdown_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1181 int ifupdown_main(int argc UNUSED_PARAM, char **argv)
1182 {
1183         int (*cmds)(struct interface_defn_t *);
1184         struct interfaces_file_t *defn;
1185         llist_t *target_list = NULL;
1186         const char *interfaces = "/etc/network/interfaces";
1187         bool any_failures = 0;
1188
1189         INIT_G();
1190
1191         G.startup_PATH = getenv("PATH");
1192         G.shell = xstrdup(get_shell_name());
1193
1194         cmds = iface_down;
1195         if (applet_name[2] == 'u') {
1196                 /* ifup command */
1197                 cmds = iface_up;
1198         }
1199
1200         getopt32(argv, OPTION_STR, &interfaces);
1201         argv += optind;
1202         if (argv[0]) {
1203                 if (DO_ALL) bb_show_usage();
1204         } else {
1205                 if (!DO_ALL) bb_show_usage();
1206         }
1207
1208         debug_noise("reading %s file:\n", interfaces);
1209         defn = read_interfaces(interfaces);
1210         debug_noise("\ndone reading %s\n\n", interfaces);
1211
1212         /* Create a list of interfaces to work on */
1213         if (DO_ALL) {
1214                 target_list = defn->autointerfaces;
1215         } else {
1216                 llist_add_to_end(&target_list, argv[0]);
1217         }
1218
1219         /* Update the interfaces */
1220         while (target_list) {
1221                 llist_t *iface_list;
1222                 struct interface_defn_t *currif;
1223                 char *iface;
1224                 char *liface;
1225                 char *pch;
1226                 bool okay = 0;
1227                 int cmds_ret;
1228
1229                 iface = xstrdup(target_list->data);
1230                 target_list = target_list->link;
1231
1232                 pch = strchr(iface, '=');
1233                 if (pch) {
1234                         *pch = '\0';
1235                         liface = xstrdup(pch + 1);
1236                 } else {
1237                         liface = xstrdup(iface);
1238                 }
1239
1240                 if (!FORCE) {
1241                         llist_t *state_list = read_iface_state();
1242                         const llist_t *iface_state = find_iface_state(state_list, iface);
1243
1244                         if (cmds == iface_up) {
1245                                 /* ifup */
1246                                 if (iface_state) {
1247                                         bb_error_msg("interface %s already configured", iface);
1248                                         goto next;
1249                                 }
1250                         } else {
1251                                 /* ifdown */
1252                                 if (!iface_state) {
1253                                         bb_error_msg("interface %s not configured", iface);
1254                                         goto next;
1255                                 }
1256                         }
1257                         llist_free(state_list, free);
1258                 }
1259
1260 #if ENABLE_FEATURE_IFUPDOWN_MAPPING
1261                 if ((cmds == iface_up) && !NO_MAPPINGS) {
1262                         struct mapping_defn_t *currmap;
1263
1264                         for (currmap = defn->mappings; currmap; currmap = currmap->next) {
1265                                 int i;
1266                                 for (i = 0; i < currmap->n_matches; i++) {
1267                                         if (fnmatch(currmap->match[i], liface, 0) != 0)
1268                                                 continue;
1269                                         if (VERBOSE) {
1270                                                 printf("Running mapping script %s on %s\n", currmap->script, liface);
1271                                         }
1272                                         liface = run_mapping(iface, currmap);
1273                                         break;
1274                                 }
1275                         }
1276                 }
1277 #endif
1278
1279                 iface_list = defn->ifaces;
1280                 while (iface_list) {
1281                         currif = (struct interface_defn_t *) iface_list->data;
1282                         if (strcmp(liface, currif->iface) == 0) {
1283                                 char *oldiface = currif->iface;
1284
1285                                 okay = 1;
1286                                 currif->iface = iface;
1287
1288                                 debug_noise("\nConfiguring interface %s (%s)\n", liface, currif->address_family->name);
1289
1290                                 /* Call the cmds function pointer, does either iface_up() or iface_down() */
1291                                 cmds_ret = cmds(currif);
1292                                 if (cmds_ret == -1) {
1293                                         bb_error_msg("don't seem to have all the variables for %s/%s",
1294                                                         liface, currif->address_family->name);
1295                                         any_failures = 1;
1296                                 } else if (cmds_ret == 0) {
1297                                         any_failures = 1;
1298                                 }
1299
1300                                 currif->iface = oldiface;
1301                         }
1302                         iface_list = iface_list->link;
1303                 }
1304                 if (VERBOSE) {
1305                         bb_putchar('\n');
1306                 }
1307
1308                 if (!okay && !FORCE) {
1309                         bb_error_msg("ignoring unknown interface %s", liface);
1310                         any_failures = 1;
1311                 } else if (!NO_ACT) {
1312                         /* update the state file */
1313                         FILE *state_fp;
1314                         llist_t *state;
1315                         llist_t *state_list = read_iface_state();
1316                         llist_t *iface_state = find_iface_state(state_list, iface);
1317
1318                         if (cmds == iface_up && !any_failures) {
1319                                 char *newiface = xasprintf("%s=%s", iface, liface);
1320                                 if (!iface_state) {
1321                                         llist_add_to_end(&state_list, newiface);
1322                                 } else {
1323                                         free(iface_state->data);
1324                                         iface_state->data = newiface;
1325                                 }
1326                         } else {
1327                                 /* Remove an interface from state_list */
1328                                 llist_unlink(&state_list, iface_state);
1329                                 free(llist_pop(&iface_state));
1330                         }
1331
1332                         /* Actually write the new state */
1333                         state_fp = xfopen_for_write(CONFIG_IFUPDOWN_IFSTATE_PATH);
1334                         state = state_list;
1335                         while (state) {
1336                                 if (state->data) {
1337                                         fprintf(state_fp, "%s\n", state->data);
1338                                 }
1339                                 state = state->link;
1340                         }
1341                         fclose(state_fp);
1342                         llist_free(state_list, free);
1343                 }
1344  next:
1345                 free(iface);
1346                 free(liface);
1347         }
1348
1349         return any_failures;
1350 }