udhcpc: fix 6rd option formatting (was using 4 more bytes than there is)
[oweals/busybox.git] / networking / udhcp / common.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
4  *
5  * Licensed under GPLv2, see file LICENSE in this source tree.
6  */
7 #include "common.h"
8
9 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
10 unsigned dhcp_verbose;
11 #endif
12
13 const uint8_t MAC_BCAST_ADDR[6] ALIGN2 = {
14         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
15 };
16
17 /* Supported options are easily added here.
18  * See RFC2132 for more options.
19  * OPTION_REQ: these options are requested by udhcpc (unless -o).
20  */
21 const struct dhcp_optflag dhcp_optflags[] = {
22         /* flags                                    code */
23         { OPTION_IP                   | OPTION_REQ, 0x01 }, /* DHCP_SUBNET        */
24         { OPTION_S32                              , 0x02 }, /* DHCP_TIME_OFFSET   */
25         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x03 }, /* DHCP_ROUTER        */
26 //      { OPTION_IP | OPTION_LIST                 , 0x04 }, /* DHCP_TIME_SERVER   */
27 //      { OPTION_IP | OPTION_LIST                 , 0x05 }, /* DHCP_NAME_SERVER   */
28         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x06 }, /* DHCP_DNS_SERVER    */
29 //      { OPTION_IP | OPTION_LIST                 , 0x07 }, /* DHCP_LOG_SERVER    */
30 //      { OPTION_IP | OPTION_LIST                 , 0x08 }, /* DHCP_COOKIE_SERVER */
31         { OPTION_IP | OPTION_LIST                 , 0x09 }, /* DHCP_LPR_SERVER    */
32         { OPTION_STRING               | OPTION_REQ, 0x0c }, /* DHCP_HOST_NAME     */
33         { OPTION_U16                              , 0x0d }, /* DHCP_BOOT_SIZE     */
34         { OPTION_STRING               | OPTION_REQ, 0x0f }, /* DHCP_DOMAIN_NAME   */
35         { OPTION_IP                               , 0x10 }, /* DHCP_SWAP_SERVER   */
36         { OPTION_STRING                           , 0x11 }, /* DHCP_ROOT_PATH     */
37         { OPTION_U8                               , 0x17 }, /* DHCP_IP_TTL        */
38         { OPTION_U16                              , 0x1a }, /* DHCP_MTU           */
39         { OPTION_IP                   | OPTION_REQ, 0x1c }, /* DHCP_BROADCAST     */
40         { OPTION_IP_PAIR | OPTION_LIST            , 0x21 }, /* DHCP_ROUTES        */
41         { OPTION_STRING                           , 0x28 }, /* DHCP_NIS_DOMAIN    */
42         { OPTION_IP | OPTION_LIST                 , 0x29 }, /* DHCP_NIS_SERVER    */
43         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x2a }, /* DHCP_NTP_SERVER    */
44         { OPTION_IP | OPTION_LIST                 , 0x2c }, /* DHCP_WINS_SERVER   */
45         { OPTION_U32                              , 0x33 }, /* DHCP_LEASE_TIME    */
46         { OPTION_IP                               , 0x36 }, /* DHCP_SERVER_ID     */
47         { OPTION_STRING                           , 0x38 }, /* DHCP_ERR_MESSAGE   */
48 //TODO: must be combined with 'sname' and 'file' handling:
49         { OPTION_STRING                           , 0x42 }, /* DHCP_TFTP_SERVER_NAME */
50         { OPTION_STRING                           , 0x43 }, /* DHCP_BOOT_FILE     */
51 //TODO: not a string, but a set of LASCII strings:
52 //      { OPTION_STRING                           , 0x4D }, /* DHCP_USER_CLASS    */
53 #if ENABLE_FEATURE_UDHCP_RFC3397
54         { OPTION_DNS_STRING | OPTION_LIST         , 0x77 }, /* DHCP_DOMAIN_SEARCH */
55         { OPTION_SIP_SERVERS                      , 0x78 }, /* DHCP_SIP_SERVERS   */
56 #endif
57         { OPTION_STATIC_ROUTES                    , 0x79 }, /* DHCP_STATIC_ROUTES */
58 #if ENABLE_FEATURE_UDHCP_8021Q
59         { OPTION_U16                              , 0x84 }, /* DHCP_VLAN_ID       */
60         { OPTION_U8                               , 0x85 }, /* DHCP_VLAN_PRIORITY */
61 #endif
62         { OPTION_6RD                              , 0xd4 }, /* DHCP_6RD           */
63         { OPTION_STATIC_ROUTES                    , 0xf9 }, /* DHCP_MS_STATIC_ROUTES */
64         { OPTION_STRING                           , 0xfc }, /* DHCP_WPAD          */
65
66         /* Options below have no match in dhcp_option_strings[],
67          * are not passed to dhcpc scripts, and cannot be specified
68          * with "option XXX YYY" syntax in dhcpd config file.
69          * These entries are only used internally by udhcp[cd]
70          * to correctly encode options into packets.
71          */
72
73         { OPTION_IP                               , 0x32 }, /* DHCP_REQUESTED_IP  */
74         { OPTION_U8                               , 0x35 }, /* DHCP_MESSAGE_TYPE  */
75         { OPTION_U16                              , 0x39 }, /* DHCP_MAX_SIZE      */
76 //looks like these opts will work just fine even without these defs:
77 //      { OPTION_STRING                           , 0x3c }, /* DHCP_VENDOR        */
78 //      /* not really a string: */
79 //      { OPTION_STRING                           , 0x3d }, /* DHCP_CLIENT_ID     */
80         { 0, 0 } /* zeroed terminating entry */
81 };
82
83 /* Used for converting options from incoming packets to env variables
84  * for udhcpc stript, and for setting options for udhcpd via
85  * "opt OPTION_NAME OPTION_VALUE" directives in udhcpd.conf file.
86  */
87 /* Must match dhcp_optflags[] order */
88 const char dhcp_option_strings[] ALIGN1 =
89         "subnet" "\0"      /* DHCP_SUBNET         */
90         "timezone" "\0"    /* DHCP_TIME_OFFSET    */
91         "router" "\0"      /* DHCP_ROUTER         */
92 //      "timesrv" "\0"     /* DHCP_TIME_SERVER    */
93 //      "namesrv" "\0"     /* DHCP_NAME_SERVER    */
94         "dns" "\0"         /* DHCP_DNS_SERVER     */
95 //      "logsrv" "\0"      /* DHCP_LOG_SERVER     */
96 //      "cookiesrv" "\0"   /* DHCP_COOKIE_SERVER  */
97         "lprsrv" "\0"      /* DHCP_LPR_SERVER     */
98         "hostname" "\0"    /* DHCP_HOST_NAME      */
99         "bootsize" "\0"    /* DHCP_BOOT_SIZE      */
100         "domain" "\0"      /* DHCP_DOMAIN_NAME    */
101         "swapsrv" "\0"     /* DHCP_SWAP_SERVER    */
102         "rootpath" "\0"    /* DHCP_ROOT_PATH      */
103         "ipttl" "\0"       /* DHCP_IP_TTL         */
104         "mtu" "\0"         /* DHCP_MTU            */
105         "broadcast" "\0"   /* DHCP_BROADCAST      */
106         "routes" "\0"      /* DHCP_ROUTES         */
107         "nisdomain" "\0"   /* DHCP_NIS_DOMAIN     */
108         "nissrv" "\0"      /* DHCP_NIS_SERVER     */
109         "ntpsrv" "\0"      /* DHCP_NTP_SERVER     */
110         "wins" "\0"        /* DHCP_WINS_SERVER    */
111         "lease" "\0"       /* DHCP_LEASE_TIME     */
112         "serverid" "\0"    /* DHCP_SERVER_ID      */
113         "message" "\0"     /* DHCP_ERR_MESSAGE    */
114         "tftp" "\0"        /* DHCP_TFTP_SERVER_NAME */
115         "bootfile" "\0"    /* DHCP_BOOT_FILE      */
116 //      "userclass" "\0"   /* DHCP_USER_CLASS     */
117 #if ENABLE_FEATURE_UDHCP_RFC3397
118         "search" "\0"      /* DHCP_DOMAIN_SEARCH  */
119 // doesn't work in udhcpd.conf since OPTION_SIP_SERVERS
120 // is not handled yet by "string->option" conversion code:
121         "sipsrv" "\0"      /* DHCP_SIP_SERVERS    */
122 #endif
123 // doesn't work in udhcpd.conf since OPTION_STATIC_ROUTES
124 // is not handled yet by "string->option" conversion code:
125         "staticroutes" "\0"/* DHCP_STATIC_ROUTES  */
126 #if ENABLE_FEATURE_UDHCP_8021Q
127         "vlanid" "\0"      /* DHCP_VLAN_ID        */
128         "vlanpriority" "\0"/* DHCP_VLAN_PRIORITY  */
129 #endif
130         "ip6rd" "\0"       /* DHCP_6RD            */
131         "msstaticroutes""\0"/* DHCP_MS_STATIC_ROUTES */
132         "wpad" "\0"        /* DHCP_WPAD           */
133         ;
134
135 /* Lengths of the option types in binary form.
136  * Used by:
137  * udhcp_str2optset: to determine how many bytes to allocate.
138  * xmalloc_optname_optval: to estimate string length
139  * from binary option length: (option[LEN] / dhcp_option_lengths[opt_type])
140  * is the number of elements, multiply in by one element's string width
141  * (len_of_option_as_string[opt_type]) and you know how wide string you need.
142  */
143 const uint8_t dhcp_option_lengths[] ALIGN1 = {
144         [OPTION_IP] =      4,
145         [OPTION_IP_PAIR] = 8,
146 //      [OPTION_BOOLEAN] = 1,
147         [OPTION_STRING] =  1,  /* ignored by udhcp_str2optset */
148 #if ENABLE_FEATURE_UDHCP_RFC3397
149         [OPTION_DNS_STRING] = 1,  /* ignored by both udhcp_str2optset and xmalloc_optname_optval */
150         [OPTION_SIP_SERVERS] = 1,
151 #endif
152         [OPTION_U8] =      1,
153         [OPTION_U16] =     2,
154 //      [OPTION_S16] =     2,
155         [OPTION_U32] =     4,
156         [OPTION_S32] =     4,
157         /* Just like OPTION_STRING, we use minimum length here */
158         [OPTION_STATIC_ROUTES] = 5,
159         [OPTION_6RD] =    22,  /* ignored by udhcp_str2optset */
160 };
161
162
163 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
164 static void log_option(const char *pfx, const uint8_t *opt)
165 {
166         if (dhcp_verbose >= 2) {
167                 char buf[256 * 2 + 2];
168                 *bin2hex(buf, (void*) (opt + OPT_DATA), opt[OPT_LEN]) = '\0';
169                 bb_info_msg("%s: 0x%02x %s", pfx, opt[OPT_CODE], buf);
170         }
171 }
172 #else
173 # define log_option(pfx, opt) ((void)0)
174 #endif
175
176 unsigned FAST_FUNC udhcp_option_idx(const char *name)
177 {
178         int n = index_in_strings(dhcp_option_strings, name);
179         if (n >= 0)
180                 return n;
181
182         {
183                 char buf[sizeof(dhcp_option_strings)];
184                 char *d = buf;
185                 const char *s = dhcp_option_strings;
186                 while (s < dhcp_option_strings + sizeof(dhcp_option_strings) - 2) {
187                         *d++ = (*s == '\0' ? ' ' : *s);
188                         s++;
189                 }
190                 *d = '\0';
191                 bb_error_msg_and_die("unknown option '%s', known options: %s", name, buf);
192         }
193 }
194
195 /* Get an option with bounds checking (warning, result is not aligned) */
196 uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code)
197 {
198         uint8_t *optionptr;
199         int len;
200         int rem;
201         int overload = 0;
202         enum {
203                 FILE_FIELD101  = FILE_FIELD  * 0x101,
204                 SNAME_FIELD101 = SNAME_FIELD * 0x101,
205         };
206
207         /* option bytes: [code][len][data1][data2]..[dataLEN] */
208         optionptr = packet->options;
209         rem = sizeof(packet->options);
210         while (1) {
211                 if (rem <= 0) {
212                         bb_error_msg("bad packet, malformed option field");
213                         return NULL;
214                 }
215                 if (optionptr[OPT_CODE] == DHCP_PADDING) {
216                         rem--;
217                         optionptr++;
218                         continue;
219                 }
220                 if (optionptr[OPT_CODE] == DHCP_END) {
221                         if ((overload & FILE_FIELD101) == FILE_FIELD) {
222                                 /* can use packet->file, and didn't look at it yet */
223                                 overload |= FILE_FIELD101; /* "we looked at it" */
224                                 optionptr = packet->file;
225                                 rem = sizeof(packet->file);
226                                 continue;
227                         }
228                         if ((overload & SNAME_FIELD101) == SNAME_FIELD) {
229                                 /* can use packet->sname, and didn't look at it yet */
230                                 overload |= SNAME_FIELD101; /* "we looked at it" */
231                                 optionptr = packet->sname;
232                                 rem = sizeof(packet->sname);
233                                 continue;
234                         }
235                         break;
236                 }
237                 len = 2 + optionptr[OPT_LEN];
238                 rem -= len;
239                 if (rem < 0)
240                         continue; /* complain and return NULL */
241
242                 if (optionptr[OPT_CODE] == code) {
243                         log_option("Option found", optionptr);
244                         return optionptr + OPT_DATA;
245                 }
246
247                 if (optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) {
248                         overload |= optionptr[OPT_DATA];
249                         /* fall through */
250                 }
251                 optionptr += len;
252         }
253
254         /* log3 because udhcpc uses it a lot - very noisy */
255         log3("Option 0x%02x not found", code);
256         return NULL;
257 }
258
259 /* Return the position of the 'end' option (no bounds checking) */
260 int FAST_FUNC udhcp_end_option(uint8_t *optionptr)
261 {
262         int i = 0;
263
264         while (optionptr[i] != DHCP_END) {
265                 if (optionptr[i] != DHCP_PADDING)
266                         i += optionptr[i + OPT_LEN] + OPT_DATA-1;
267                 i++;
268         }
269         return i;
270 }
271
272 /* Add an option (supplied in binary form) to the options.
273  * Option format: [code][len][data1][data2]..[dataLEN]
274  */
275 void FAST_FUNC udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt)
276 {
277         unsigned len;
278         uint8_t *optionptr = packet->options;
279         unsigned end = udhcp_end_option(optionptr);
280
281         len = OPT_DATA + addopt[OPT_LEN];
282         /* end position + (option code/length + addopt length) + end option */
283         if (end + len + 1 >= DHCP_OPTIONS_BUFSIZE) {
284 //TODO: learn how to use overflow option if we exhaust packet->options[]
285                 bb_error_msg("option 0x%02x did not fit into the packet",
286                                 addopt[OPT_CODE]);
287                 return;
288         }
289         log_option("Adding option", addopt);
290         memcpy(optionptr + end, addopt, len);
291         optionptr[end + len] = DHCP_END;
292 }
293
294 /* Add an one to four byte option to a packet */
295 void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data)
296 {
297         const struct dhcp_optflag *dh;
298
299         for (dh = dhcp_optflags; dh->code; dh++) {
300                 if (dh->code == code) {
301                         uint8_t option[6], len;
302
303                         option[OPT_CODE] = code;
304                         len = dhcp_option_lengths[dh->flags & OPTION_TYPE_MASK];
305                         option[OPT_LEN] = len;
306                         if (BB_BIG_ENDIAN)
307                                 data <<= 8 * (4 - len);
308                         /* Assignment is unaligned! */
309                         move_to_unaligned32(&option[OPT_DATA], data);
310                         udhcp_add_binary_option(packet, option);
311                         return;
312                 }
313         }
314
315         bb_error_msg("can't add option 0x%02x", code);
316 }
317
318 /* Find option 'code' in opt_list */
319 struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code)
320 {
321         while (opt_list && opt_list->data[OPT_CODE] < code)
322                 opt_list = opt_list->next;
323
324         if (opt_list && opt_list->data[OPT_CODE] == code)
325                 return opt_list;
326         return NULL;
327 }
328
329 /* Parse string to IP in network order */
330 int FAST_FUNC udhcp_str2nip(const char *str, void *arg)
331 {
332         len_and_sockaddr *lsa;
333
334         lsa = host_and_af2sockaddr(str, 0, AF_INET);
335         if (!lsa)
336                 return 0;
337         *(uint32_t*)arg = lsa->u.sin.sin_addr.s_addr;
338         free(lsa);
339         return 1;
340 }
341
342 /* udhcp_str2optset:
343  * Parse string option representation to binary form and add it to opt_list.
344  * Called to parse "udhcpc -x OPTNAME:OPTVAL"
345  * and to parse udhcpd.conf's "opt OPTNAME OPTVAL" directives.
346  */
347 /* helper for the helper */
348 static char *allocate_tempopt_if_needed(
349                 const struct dhcp_optflag *optflag,
350                 char *buffer,
351                 int *length_p)
352 {
353         char *allocated = NULL;
354         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_BIN) {
355                 const char *end;
356                 allocated = xstrdup(buffer); /* more than enough */
357                 end = hex2bin(allocated, buffer, 255);
358                 if (errno)
359                         bb_error_msg_and_die("malformed hex string '%s'", buffer);
360                 *length_p = end - allocated;
361         }
362         return allocated;
363 }
364 /* helper: add an option to the opt_list */
365 static NOINLINE void attach_option(
366                 struct option_set **opt_list,
367                 const struct dhcp_optflag *optflag,
368                 char *buffer,
369                 int length)
370 {
371         struct option_set *existing, *new, **curr;
372         char *allocated = NULL;
373
374         existing = udhcp_find_option(*opt_list, optflag->code);
375         if (!existing) {
376                 log2("Attaching option %02x to list", optflag->code);
377                 allocated = allocate_tempopt_if_needed(optflag, buffer, &length);
378 #if ENABLE_FEATURE_UDHCP_RFC3397
379                 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
380                         /* reuse buffer and length for RFC1035-formatted string */
381                         allocated = buffer = (char *)dname_enc(NULL, 0, buffer, &length);
382                 }
383 #endif
384                 /* make a new option */
385                 new = xmalloc(sizeof(*new));
386                 new->data = xmalloc(length + OPT_DATA);
387                 new->data[OPT_CODE] = optflag->code;
388                 new->data[OPT_LEN] = length;
389                 memcpy(new->data + OPT_DATA, (allocated ? allocated : buffer), length);
390
391                 curr = opt_list;
392                 while (*curr && (*curr)->data[OPT_CODE] < optflag->code)
393                         curr = &(*curr)->next;
394
395                 new->next = *curr;
396                 *curr = new;
397                 goto ret;
398         }
399
400         if (optflag->flags & OPTION_LIST) {
401                 unsigned old_len;
402
403                 /* add it to an existing option */
404                 log2("Attaching option %02x to existing member of list", optflag->code);
405                 allocated = allocate_tempopt_if_needed(optflag, buffer, &length);
406                 old_len = existing->data[OPT_LEN];
407 #if ENABLE_FEATURE_UDHCP_RFC3397
408                 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
409                         /* reuse buffer and length for RFC1035-formatted string */
410                         allocated = buffer = (char *)dname_enc(existing->data + OPT_DATA, old_len, buffer, &length);
411                 }
412 #endif
413                 if (old_len + length < 255) {
414                         /* actually 255 is ok too, but adding a space can overlow it */
415
416                         existing->data = xrealloc(existing->data, OPT_DATA + 1 + old_len + length);
417                         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING) {
418                                 /* add space separator between STRING options in a list */
419                                 existing->data[OPT_DATA + old_len] = ' ';
420                                 old_len++;
421                         }
422                         memcpy(existing->data + OPT_DATA + old_len, buffer, length);
423                         existing->data[OPT_LEN] = old_len + length;
424                 } /* else, ignore the data, we could put this in a second option in the future */
425         } /* else, ignore the new data */
426
427  ret:
428         free(allocated);
429 }
430
431 int FAST_FUNC udhcp_str2optset(const char *const_str, void *arg)
432 {
433         struct option_set **opt_list = arg;
434         char *opt, *val, *endptr;
435         char *str;
436         const struct dhcp_optflag *optflag;
437         struct dhcp_optflag bin_optflag;
438         unsigned optcode;
439         int retval, length;
440         char buffer[8] ALIGNED(4);
441         uint16_t *result_u16 = (uint16_t *) buffer;
442         uint32_t *result_u32 = (uint32_t *) buffer;
443
444         /* Cheat, the only *const* str possible is "" */
445         str = (char *) const_str;
446         opt = strtok(str, " \t=");
447         if (!opt)
448                 return 0;
449
450         optcode = bb_strtou(opt, NULL, 0);
451         if (!errno && optcode < 255) {
452                 /* Raw (numeric) option code */
453                 bin_optflag.flags = OPTION_BIN;
454                 bin_optflag.code = optcode;
455                 optflag = &bin_optflag;
456         } else {
457                 optflag = &dhcp_optflags[udhcp_option_idx(opt)];
458         }
459
460         retval = 0;
461         do {
462                 val = strtok(NULL, ", \t");
463                 if (!val)
464                         break;
465                 length = dhcp_option_lengths[optflag->flags & OPTION_TYPE_MASK];
466                 retval = 0;
467                 opt = buffer; /* new meaning for variable opt */
468                 switch (optflag->flags & OPTION_TYPE_MASK) {
469                 case OPTION_IP:
470                         retval = udhcp_str2nip(val, buffer);
471                         break;
472                 case OPTION_IP_PAIR:
473                         retval = udhcp_str2nip(val, buffer);
474                         val = strtok(NULL, ", \t/-");
475                         if (!val)
476                                 retval = 0;
477                         if (retval)
478                                 retval = udhcp_str2nip(val, buffer + 4);
479                         break;
480                 case OPTION_STRING:
481 #if ENABLE_FEATURE_UDHCP_RFC3397
482                 case OPTION_DNS_STRING:
483 #endif
484                         length = strnlen(val, 254);
485                         if (length > 0) {
486                                 opt = val;
487                                 retval = 1;
488                         }
489                         break;
490 //              case OPTION_BOOLEAN: {
491 //                      static const char no_yes[] ALIGN1 = "no\0yes\0";
492 //                      buffer[0] = retval = index_in_strings(no_yes, val);
493 //                      retval++; /* 0 - bad; 1: "no" 2: "yes" */
494 //                      break;
495 //              }
496                 case OPTION_U8:
497                         buffer[0] = strtoul(val, &endptr, 0);
498                         retval = (endptr[0] == '\0');
499                         break;
500                 /* htonX are macros in older libc's, using temp var
501                  * in code below for safety */
502                 /* TODO: use bb_strtoX? */
503                 case OPTION_U16: {
504                         unsigned long tmp = strtoul(val, &endptr, 0);
505                         *result_u16 = htons(tmp);
506                         retval = (endptr[0] == '\0' /*&& tmp < 0x10000*/);
507                         break;
508                 }
509 //              case OPTION_S16: {
510 //                      long tmp = strtol(val, &endptr, 0);
511 //                      *result_u16 = htons(tmp);
512 //                      retval = (endptr[0] == '\0');
513 //                      break;
514 //              }
515                 case OPTION_U32: {
516                         unsigned long tmp = strtoul(val, &endptr, 0);
517                         *result_u32 = htonl(tmp);
518                         retval = (endptr[0] == '\0');
519                         break;
520                 }
521                 case OPTION_S32: {
522                         long tmp = strtol(val, &endptr, 0);
523                         *result_u32 = htonl(tmp);
524                         retval = (endptr[0] == '\0');
525                         break;
526                 }
527                 case OPTION_BIN: /* handled in attach_option() */
528                         opt = val;
529                         retval = 1;
530                 default:
531                         break;
532                 }
533                 if (retval)
534                         attach_option(opt_list, optflag, opt, length);
535         } while (retval && optflag->flags & OPTION_LIST);
536
537         return retval;
538 }