1 | /* Copyright (C) 1996-2017 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | Contributed by Thorsten Kukuk <kukuk@suse.de>, 1996. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <assert.h> |
20 | #include <nss.h> |
21 | #include <ctype.h> |
22 | /* The following is an ugly trick to avoid a prototype declaration for |
23 | _nss_nis_endgrent. */ |
24 | #define _nss_nis_endhostent _nss_nis_endhostent_XXX |
25 | #include <netdb.h> |
26 | #undef _nss_nis_endhostent |
27 | #include <string.h> |
28 | #include <netinet/in.h> |
29 | #include <arpa/inet.h> |
30 | #include <resolv/resolv-internal.h> |
31 | #include <libc-lock.h> |
32 | #include <rpcsvc/yp.h> |
33 | #include <rpcsvc/ypclnt.h> |
34 | |
35 | #include "nss-nis.h" |
36 | |
37 | /* Get implementation for some internal functions. */ |
38 | #include <resolv/mapv4v6addr.h> |
39 | |
40 | #define ENTNAME hostent |
41 | #define DATABASE "hosts" |
42 | #define NEED_H_ERRNO |
43 | |
44 | #define , af, flags |
45 | #define , int af, int flags |
46 | |
47 | #define ENTDATA hostent_data |
48 | struct hostent_data |
49 | { |
50 | unsigned char host_addr[16]; /* IPv4 or IPv6 address. */ |
51 | char *h_addr_ptrs[2]; /* Points to that and null terminator. */ |
52 | }; |
53 | |
54 | #define TRAILING_LIST_MEMBER h_aliases |
55 | #define TRAILING_LIST_SEPARATOR_P isspace |
56 | #include <nss/nss_files/files-parse.c> |
57 | LINE_PARSER |
58 | ("#" , |
59 | { |
60 | char *addr; |
61 | |
62 | STRING_FIELD (addr, isspace, 1); |
63 | |
64 | assert (af == AF_INET || af == AF_INET6 || af == AF_UNSPEC); |
65 | |
66 | /* Parse address. */ |
67 | if (af != AF_INET6 && inet_pton (AF_INET, addr, entdata->host_addr) > 0) |
68 | { |
69 | assert ((flags & AI_V4MAPPED) == 0 || af != AF_UNSPEC); |
70 | if (flags & AI_V4MAPPED) |
71 | { |
72 | map_v4v6_address ((char *) entdata->host_addr, |
73 | (char *) entdata->host_addr); |
74 | result->h_addrtype = AF_INET6; |
75 | result->h_length = IN6ADDRSZ; |
76 | } |
77 | else |
78 | { |
79 | result->h_addrtype = AF_INET; |
80 | result->h_length = INADDRSZ; |
81 | } |
82 | } |
83 | else if (af != AF_INET |
84 | && inet_pton (AF_INET6, addr, entdata->host_addr) > 0) |
85 | { |
86 | result->h_addrtype = AF_INET6; |
87 | result->h_length = IN6ADDRSZ; |
88 | } |
89 | else |
90 | /* Illegal address: ignore line. */ |
91 | return 0; |
92 | |
93 | /* Store a pointer to the address in the expected form. */ |
94 | entdata->h_addr_ptrs[0] = (char *) entdata->host_addr; |
95 | entdata->h_addr_ptrs[1] = NULL; |
96 | result->h_addr_list = entdata->h_addr_ptrs; |
97 | |
98 | STRING_FIELD (result->h_name, isspace, 1); |
99 | }) |
100 | |
101 | |
102 | __libc_lock_define_initialized (static, lock) |
103 | |
104 | static bool_t new_start = 1; |
105 | static char *oldkey = NULL; |
106 | static int oldkeylen = 0; |
107 | |
108 | |
109 | enum nss_status |
110 | _nss_nis_sethostent (int stayopen) |
111 | { |
112 | __libc_lock_lock (lock); |
113 | |
114 | new_start = 1; |
115 | if (oldkey != NULL) |
116 | { |
117 | free (oldkey); |
118 | oldkey = NULL; |
119 | oldkeylen = 0; |
120 | } |
121 | |
122 | __libc_lock_unlock (lock); |
123 | |
124 | return NSS_STATUS_SUCCESS; |
125 | } |
126 | /* Make _nss_nis_endhostent an alias of _nss_nis_sethostent. We do this |
127 | even though the prototypes don't match. The argument of sethostent |
128 | is used so this makes no difference. */ |
129 | strong_alias (_nss_nis_sethostent, _nss_nis_endhostent) |
130 | |
131 | |
132 | /* The calling function always need to get a lock first. */ |
133 | static enum nss_status |
134 | internal_nis_gethostent_r (struct hostent *host, char *buffer, |
135 | size_t buflen, int *errnop, int *h_errnop, |
136 | int af, int flags) |
137 | { |
138 | char *domain; |
139 | if (__glibc_unlikely (yp_get_default_domain (&domain))) |
140 | return NSS_STATUS_UNAVAIL; |
141 | |
142 | uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct parser_data); |
143 | buffer += pad; |
144 | |
145 | struct parser_data *data = (void *) buffer; |
146 | if (__glibc_unlikely (buflen < sizeof *data + 1 + pad)) |
147 | { |
148 | *errnop = ERANGE; |
149 | *h_errnop = NETDB_INTERNAL; |
150 | return NSS_STATUS_TRYAGAIN; |
151 | } |
152 | buflen -= pad; |
153 | |
154 | /* Get the next entry until we found a correct one. */ |
155 | const size_t linebuflen = buffer + buflen - data->linebuffer; |
156 | int parse_res; |
157 | do |
158 | { |
159 | char *result; |
160 | int len; |
161 | char *outkey; |
162 | int keylen; |
163 | int yperr; |
164 | if (new_start) |
165 | yperr = yp_first (domain, "hosts.byname" , &outkey, &keylen, &result, |
166 | &len); |
167 | else |
168 | yperr = yp_next (domain, "hosts.byname" , oldkey, oldkeylen, &outkey, |
169 | &keylen, &result, &len); |
170 | |
171 | if (__glibc_unlikely (yperr != YPERR_SUCCESS)) |
172 | { |
173 | enum nss_status retval = yperr2nss (yperr); |
174 | |
175 | switch (retval) |
176 | { |
177 | case NSS_STATUS_TRYAGAIN: |
178 | *errnop = errno; |
179 | *h_errnop = TRY_AGAIN; |
180 | break; |
181 | case NSS_STATUS_NOTFOUND: |
182 | *h_errnop = HOST_NOT_FOUND; |
183 | break; |
184 | default: |
185 | *h_errnop = NO_RECOVERY; |
186 | break; |
187 | } |
188 | return retval; |
189 | } |
190 | |
191 | if (__glibc_unlikely ((size_t) (len + 1) > linebuflen)) |
192 | { |
193 | free (result); |
194 | *h_errnop = NETDB_INTERNAL; |
195 | *errnop = ERANGE; |
196 | return NSS_STATUS_TRYAGAIN; |
197 | } |
198 | |
199 | char *p = strncpy (data->linebuffer, result, len); |
200 | data->linebuffer[len] = '\0'; |
201 | while (isspace (*p)) |
202 | ++p; |
203 | free (result); |
204 | |
205 | parse_res = parse_line (p, host, data, buflen, errnop, af, flags); |
206 | if (__glibc_unlikely (parse_res == -1)) |
207 | { |
208 | free (outkey); |
209 | *h_errnop = NETDB_INTERNAL; |
210 | *errnop = ERANGE; |
211 | return NSS_STATUS_TRYAGAIN; |
212 | } |
213 | free (oldkey); |
214 | oldkey = outkey; |
215 | oldkeylen = keylen; |
216 | new_start = 0; |
217 | } |
218 | while (!parse_res); |
219 | |
220 | *h_errnop = NETDB_SUCCESS; |
221 | return NSS_STATUS_SUCCESS; |
222 | } |
223 | |
224 | |
225 | enum nss_status |
226 | _nss_nis_gethostent_r (struct hostent *host, char *buffer, size_t buflen, |
227 | int *errnop, int *h_errnop) |
228 | { |
229 | enum nss_status status; |
230 | |
231 | __libc_lock_lock (lock); |
232 | |
233 | status = internal_nis_gethostent_r (host, buffer, buflen, errnop, h_errnop, |
234 | (res_use_inet6 () ? AF_INET6 : AF_INET), |
235 | (res_use_inet6 () ? AI_V4MAPPED : 0 )); |
236 | |
237 | __libc_lock_unlock (lock); |
238 | |
239 | return status; |
240 | } |
241 | |
242 | |
243 | static enum nss_status |
244 | internal_gethostbyname2_r (const char *name, int af, struct hostent *host, |
245 | char *buffer, size_t buflen, int *errnop, |
246 | int *h_errnop, int flags) |
247 | { |
248 | uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct parser_data); |
249 | buffer += pad; |
250 | |
251 | struct parser_data *data = (void *) buffer; |
252 | |
253 | if (name == NULL) |
254 | { |
255 | *errnop = EINVAL; |
256 | return NSS_STATUS_UNAVAIL; |
257 | } |
258 | |
259 | char *domain; |
260 | if (yp_get_default_domain (&domain)) |
261 | return NSS_STATUS_UNAVAIL; |
262 | |
263 | if (buflen < sizeof *data + 1 + pad) |
264 | { |
265 | *h_errnop = NETDB_INTERNAL; |
266 | *errnop = ERANGE; |
267 | return NSS_STATUS_TRYAGAIN; |
268 | } |
269 | buflen -= pad; |
270 | |
271 | /* Convert name to lowercase. */ |
272 | size_t namlen = strlen (name); |
273 | /* Limit name length to the maximum size of an RPC packet. */ |
274 | if (namlen > UDPMSGSIZE) |
275 | { |
276 | *errnop = ERANGE; |
277 | return NSS_STATUS_UNAVAIL; |
278 | } |
279 | |
280 | char name2[namlen + 1]; |
281 | size_t i; |
282 | |
283 | for (i = 0; i < namlen; ++i) |
284 | name2[i] = tolower (name[i]); |
285 | name2[i] = '\0'; |
286 | |
287 | char *result; |
288 | int len; |
289 | int yperr = yp_match (domain, "hosts.byname" , name2, namlen, &result, &len); |
290 | |
291 | if (__glibc_unlikely (yperr != YPERR_SUCCESS)) |
292 | { |
293 | enum nss_status retval = yperr2nss (yperr); |
294 | |
295 | if (retval == NSS_STATUS_TRYAGAIN) |
296 | { |
297 | *h_errnop = TRY_AGAIN; |
298 | *errnop = errno; |
299 | } |
300 | if (retval == NSS_STATUS_NOTFOUND) |
301 | *h_errnop = HOST_NOT_FOUND; |
302 | return retval; |
303 | } |
304 | |
305 | const size_t linebuflen = buffer + buflen - data->linebuffer; |
306 | if (__glibc_unlikely ((size_t) (len + 1) > linebuflen)) |
307 | { |
308 | free (result); |
309 | *h_errnop = NETDB_INTERNAL; |
310 | *errnop = ERANGE; |
311 | return NSS_STATUS_TRYAGAIN; |
312 | } |
313 | |
314 | char *p = strncpy (data->linebuffer, result, len); |
315 | data->linebuffer[len] = '\0'; |
316 | while (isspace (*p)) |
317 | ++p; |
318 | free (result); |
319 | |
320 | int parse_res = parse_line (p, host, data, buflen, errnop, af, flags); |
321 | |
322 | if (__glibc_unlikely (parse_res < 1 || host->h_addrtype != af)) |
323 | { |
324 | if (parse_res == -1) |
325 | { |
326 | *h_errnop = NETDB_INTERNAL; |
327 | return NSS_STATUS_TRYAGAIN; |
328 | } |
329 | else |
330 | { |
331 | *h_errnop = HOST_NOT_FOUND; |
332 | return NSS_STATUS_NOTFOUND; |
333 | } |
334 | } |
335 | |
336 | *h_errnop = NETDB_SUCCESS; |
337 | return NSS_STATUS_SUCCESS; |
338 | } |
339 | |
340 | |
341 | enum nss_status |
342 | _nss_nis_gethostbyname2_r (const char *name, int af, struct hostent *host, |
343 | char *buffer, size_t buflen, int *errnop, |
344 | int *h_errnop) |
345 | { |
346 | if (af != AF_INET && af != AF_INET6) |
347 | { |
348 | *h_errnop = HOST_NOT_FOUND; |
349 | return NSS_STATUS_NOTFOUND; |
350 | } |
351 | |
352 | return internal_gethostbyname2_r (name, af, host, buffer, buflen, errnop, |
353 | h_errnop, |
354 | (res_use_inet6 () ? AI_V4MAPPED : 0)); |
355 | } |
356 | |
357 | |
358 | enum nss_status |
359 | _nss_nis_gethostbyname_r (const char *name, struct hostent *host, char *buffer, |
360 | size_t buflen, int *errnop, int *h_errnop) |
361 | { |
362 | if (res_use_inet6 ()) |
363 | { |
364 | enum nss_status status; |
365 | |
366 | status = internal_gethostbyname2_r (name, AF_INET6, host, buffer, buflen, |
367 | errnop, h_errnop, AI_V4MAPPED); |
368 | if (status == NSS_STATUS_SUCCESS) |
369 | return status; |
370 | } |
371 | |
372 | return internal_gethostbyname2_r (name, AF_INET, host, buffer, buflen, |
373 | errnop, h_errnop, 0); |
374 | } |
375 | |
376 | |
377 | enum nss_status |
378 | _nss_nis_gethostbyaddr_r (const void *addr, socklen_t addrlen, int af, |
379 | struct hostent *host, char *buffer, size_t buflen, |
380 | int *errnop, int *h_errnop) |
381 | { |
382 | char *domain; |
383 | if (__glibc_unlikely (yp_get_default_domain (&domain))) |
384 | return NSS_STATUS_UNAVAIL; |
385 | |
386 | uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct parser_data); |
387 | buffer += pad; |
388 | |
389 | struct parser_data *data = (void *) buffer; |
390 | if (__glibc_unlikely (buflen < sizeof *data + 1 + pad)) |
391 | { |
392 | *errnop = ERANGE; |
393 | *h_errnop = NETDB_INTERNAL; |
394 | return NSS_STATUS_TRYAGAIN; |
395 | } |
396 | buflen -= pad; |
397 | |
398 | char *buf = inet_ntoa (*(const struct in_addr *) addr); |
399 | |
400 | char *result; |
401 | int len; |
402 | int yperr = yp_match (domain, "hosts.byaddr" , buf, strlen (buf), &result, |
403 | &len); |
404 | |
405 | if (__glibc_unlikely (yperr != YPERR_SUCCESS)) |
406 | { |
407 | enum nss_status retval = yperr2nss (yperr); |
408 | |
409 | if (retval == NSS_STATUS_TRYAGAIN) |
410 | { |
411 | *h_errnop = TRY_AGAIN; |
412 | *errnop = errno; |
413 | } |
414 | else if (retval == NSS_STATUS_NOTFOUND) |
415 | *h_errnop = HOST_NOT_FOUND; |
416 | |
417 | return retval; |
418 | } |
419 | |
420 | const size_t linebuflen = buffer + buflen - data->linebuffer; |
421 | if (__glibc_unlikely ((size_t) (len + 1) > linebuflen)) |
422 | { |
423 | free (result); |
424 | *errnop = ERANGE; |
425 | *h_errnop = NETDB_INTERNAL; |
426 | return NSS_STATUS_TRYAGAIN; |
427 | } |
428 | |
429 | char *p = strncpy (data->linebuffer, result, len); |
430 | data->linebuffer[len] = '\0'; |
431 | while (isspace (*p)) |
432 | ++p; |
433 | free (result); |
434 | |
435 | int parse_res = parse_line (p, host, data, buflen, errnop, af, |
436 | (res_use_inet6 () ? AI_V4MAPPED : 0)); |
437 | if (__glibc_unlikely (parse_res < 1)) |
438 | { |
439 | if (parse_res == -1) |
440 | { |
441 | *h_errnop = NETDB_INTERNAL; |
442 | return NSS_STATUS_TRYAGAIN; |
443 | } |
444 | else |
445 | { |
446 | *h_errnop = HOST_NOT_FOUND; |
447 | return NSS_STATUS_NOTFOUND; |
448 | } |
449 | } |
450 | |
451 | *h_errnop = NETDB_SUCCESS; |
452 | return NSS_STATUS_SUCCESS; |
453 | } |
454 | |
455 | |
456 | enum nss_status |
457 | _nss_nis_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat, |
458 | char *buffer, size_t buflen, int *errnop, |
459 | int *herrnop, int32_t *ttlp) |
460 | { |
461 | char *domain; |
462 | if (yp_get_default_domain (&domain)) |
463 | { |
464 | *herrnop = NO_DATA; |
465 | return NSS_STATUS_UNAVAIL; |
466 | } |
467 | |
468 | /* Convert name to lowercase. */ |
469 | size_t namlen = strlen (name); |
470 | /* Limit name length to the maximum size of an RPC packet. */ |
471 | if (namlen > UDPMSGSIZE) |
472 | { |
473 | *errnop = ERANGE; |
474 | return NSS_STATUS_UNAVAIL; |
475 | } |
476 | |
477 | char name2[namlen + 1]; |
478 | size_t i; |
479 | |
480 | for (i = 0; i < namlen; ++i) |
481 | name2[i] = tolower (name[i]); |
482 | name2[i] = '\0'; |
483 | |
484 | char *result; |
485 | int len; |
486 | int yperr = yp_match (domain, "hosts.byname" , name2, namlen, &result, &len); |
487 | |
488 | if (__glibc_unlikely (yperr != YPERR_SUCCESS)) |
489 | { |
490 | enum nss_status retval = yperr2nss (yperr); |
491 | |
492 | if (retval == NSS_STATUS_TRYAGAIN) |
493 | { |
494 | *herrnop = TRY_AGAIN; |
495 | *errnop = errno; |
496 | } |
497 | if (retval == NSS_STATUS_NOTFOUND) |
498 | *herrnop = HOST_NOT_FOUND; |
499 | return retval; |
500 | } |
501 | |
502 | if (*pat == NULL) |
503 | { |
504 | uintptr_t pad = (-(uintptr_t) buffer |
505 | % __alignof__ (struct gaih_addrtuple)); |
506 | buffer += pad; |
507 | buflen = buflen > pad ? buflen - pad : 0; |
508 | |
509 | if (__glibc_unlikely (buflen < sizeof (struct gaih_addrtuple))) |
510 | { |
511 | erange: |
512 | free (result); |
513 | *errnop = ERANGE; |
514 | *herrnop = NETDB_INTERNAL; |
515 | return NSS_STATUS_TRYAGAIN; |
516 | } |
517 | |
518 | *pat = (struct gaih_addrtuple *) buffer; |
519 | buffer += sizeof (struct gaih_addrtuple); |
520 | buflen -= sizeof (struct gaih_addrtuple); |
521 | } |
522 | |
523 | uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct parser_data); |
524 | buffer += pad; |
525 | |
526 | struct parser_data *data = (void *) buffer; |
527 | |
528 | if (__glibc_unlikely (buflen < sizeof *data + 1 + pad)) |
529 | goto erange; |
530 | buflen -= pad; |
531 | |
532 | struct hostent host; |
533 | int parse_res = parse_line (result, &host, data, buflen, errnop, AF_UNSPEC, |
534 | 0); |
535 | if (__glibc_unlikely (parse_res < 1)) |
536 | { |
537 | if (parse_res == -1) |
538 | { |
539 | *herrnop = NETDB_INTERNAL; |
540 | return NSS_STATUS_TRYAGAIN; |
541 | } |
542 | else |
543 | { |
544 | *herrnop = HOST_NOT_FOUND; |
545 | return NSS_STATUS_NOTFOUND; |
546 | } |
547 | } |
548 | |
549 | (*pat)->next = NULL; |
550 | (*pat)->family = host.h_addrtype; |
551 | memcpy ((*pat)->addr, host.h_addr_list[0], host.h_length); |
552 | (*pat)->scopeid = 0; |
553 | assert (host.h_addr_list[1] == NULL); |
554 | |
555 | /* Undo the alignment for parser_data. */ |
556 | buffer -= pad; |
557 | buflen += pad; |
558 | |
559 | size_t h_name_len = strlen (host.h_name) + 1; |
560 | if (h_name_len >= buflen) |
561 | goto erange; |
562 | (*pat)->name = memcpy (buffer, host.h_name, h_name_len); |
563 | |
564 | free (result); |
565 | |
566 | return NSS_STATUS_SUCCESS; |
567 | } |
568 | |