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@vt.uni-paderborn.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 <ctype.h>
21#include <errno.h>
22#include <nss.h>
23#include <pwd.h>
24#include <string.h>
25#include <libc-lock.h>
26#include <rpcsvc/yp.h>
27#include <rpcsvc/ypclnt.h>
28
29#include "nss-nis.h"
30#include <libnsl.h>
31
32/* Get the declaration of the parser function. */
33#define ENTNAME pwent
34#define STRUCTURE passwd
35#define EXTERN_PARSER
36#include <nss/nss_files/files-parse.c>
37
38/* Protect global state against multiple changers */
39__libc_lock_define_initialized (static, lock)
40
41static bool new_start = true;
42static char *oldkey;
43static int oldkeylen;
44static intern_t intern;
45
46
47int
48_nis_saveit (int instatus, char *inkey, int inkeylen, char *inval,
49 int invallen, char *indata)
50{
51 intern_t *intern = (intern_t *) indata;
52
53 if (instatus != YP_TRUE)
54 return 1;
55
56 if (inkey && inkeylen > 0 && inval && invallen > 0)
57 {
58 struct response_t *bucket = intern->next;
59
60 if (__glibc_unlikely (bucket == NULL))
61 {
62#define MINSIZE 4096 - 4 * sizeof (void *)
63 const size_t minsize = MAX (MINSIZE, 2 * (invallen + 1));
64 bucket = malloc (sizeof (struct response_t) + minsize);
65 if (bucket == NULL)
66 /* We have no error code for out of memory. */
67 return 1;
68
69 bucket->next = NULL;
70 bucket->size = minsize;
71 intern->start = intern->next = bucket;
72 intern->offset = 0;
73 }
74 else if (__builtin_expect (invallen + 1 > bucket->size - intern->offset,
75 0))
76 {
77 /* We need a new (larger) buffer. */
78 const size_t newsize = 2 * MAX (bucket->size, invallen + 1);
79 struct response_t *newp = malloc (sizeof (struct response_t)
80 + newsize);
81 if (newp == NULL)
82 /* We have no error code for out of memory. */
83 return 1;
84
85 /* Mark the old bucket as full. */
86 bucket->size = intern->offset;
87
88 newp->next = NULL;
89 newp->size = newsize;
90 bucket = intern->next = bucket->next = newp;
91 intern->offset = 0;
92 }
93
94 char *p = mempcpy (&bucket->mem[intern->offset], inval, invallen);
95 if (__glibc_unlikely (p[-1] != '\0'))
96 {
97 *p = '\0';
98 ++invallen;
99 }
100 intern->offset += invallen;
101 }
102
103 return 0;
104}
105
106
107static void
108internal_nis_endpwent (void)
109{
110 new_start = true;
111 free (oldkey);
112 oldkey = NULL;
113 oldkeylen = 0;
114
115 struct response_t *curr = intern.start;
116
117 while (curr != NULL)
118 {
119 struct response_t *last = curr;
120 curr = curr->next;
121 free (last);
122 }
123
124 intern.next = intern.start = NULL;
125}
126
127
128enum nss_status
129_nss_nis_endpwent (void)
130{
131 __libc_lock_lock (lock);
132
133 internal_nis_endpwent ();
134
135 __libc_lock_unlock (lock);
136
137 return NSS_STATUS_SUCCESS;
138}
139
140
141enum nss_status
142internal_nis_setpwent (void)
143{
144 /* We have to read all the data now. */
145 char *domain;
146 if (__glibc_unlikely (yp_get_default_domain (&domain)))
147 return NSS_STATUS_UNAVAIL;
148
149 struct ypall_callback ypcb;
150
151 ypcb.foreach = _nis_saveit;
152 ypcb.data = (char *) &intern;
153 enum nss_status status = yperr2nss (yp_all (domain, "passwd.byname", &ypcb));
154
155
156 /* Mark the last buffer as full. */
157 if (intern.next != NULL)
158 intern.next->size = intern.offset;
159
160 intern.next = intern.start;
161 intern.offset = 0;
162
163 return status;
164}
165
166
167enum nss_status
168_nss_nis_setpwent (int stayopen)
169{
170 enum nss_status result = NSS_STATUS_SUCCESS;
171
172 __libc_lock_lock (lock);
173
174 internal_nis_endpwent ();
175
176 if (_nsl_default_nss () & NSS_FLAG_SETENT_BATCH_READ)
177 result = internal_nis_setpwent ();
178
179 __libc_lock_unlock (lock);
180
181 return result;
182}
183
184
185static enum nss_status
186internal_nis_getpwent_r (struct passwd *pwd, char *buffer, size_t buflen,
187 int *errnop)
188{
189 /* If we read the entire database at setpwent time we just iterate
190 over the data we have in memory. */
191 bool batch_read = intern.start != NULL;
192
193 char *domain = NULL;
194 if (!batch_read && __builtin_expect (yp_get_default_domain (&domain), 0))
195 return NSS_STATUS_UNAVAIL;
196
197 /* Get the next entry until we found a correct one. */
198 int parse_res;
199 do
200 {
201 char *result;
202 char *outkey;
203 int len;
204 int keylen;
205
206 if (batch_read)
207 {
208 struct response_t *bucket;
209
210 handle_batch_read:
211 bucket = intern.next;
212
213 if (__glibc_unlikely (intern.offset >= bucket->size))
214 {
215 if (bucket->next == NULL)
216 return NSS_STATUS_NOTFOUND;
217
218 /* We look at all the content in the current bucket. Go on
219 to the next. */
220 bucket = intern.next = bucket->next;
221 intern.offset = 0;
222 }
223
224 for (result = &bucket->mem[intern.offset]; isspace (*result);
225 ++result)
226 ++intern.offset;
227
228 len = strlen (result);
229 }
230 else
231 {
232 int yperr;
233
234 if (new_start)
235 {
236 /* Maybe we should read the database in one piece. */
237 if ((_nsl_default_nss () & NSS_FLAG_SETENT_BATCH_READ)
238 && internal_nis_setpwent () == NSS_STATUS_SUCCESS
239 && intern.start != NULL)
240 {
241 batch_read = true;
242 goto handle_batch_read;
243 }
244
245 yperr = yp_first (domain, "passwd.byname", &outkey, &keylen,
246 &result, &len);
247 }
248 else
249 yperr = yp_next (domain, "passwd.byname", oldkey, oldkeylen,
250 &outkey, &keylen, &result, &len);
251
252 if (__glibc_unlikely (yperr != YPERR_SUCCESS))
253 {
254 enum nss_status retval = yperr2nss (yperr);
255
256 if (retval == NSS_STATUS_TRYAGAIN)
257 *errnop = errno;
258 return retval;
259 }
260 }
261
262 /* Check for adjunct style secret passwords. They can be
263 recognized by a password starting with "##". We do not use
264 it if the passwd.adjunct.byname table is supposed to be used
265 as a shadow.byname replacement. */
266 char *p = strchr (result, ':');
267 size_t namelen;
268 char *result2;
269 int len2;
270 if ((_nsl_default_nss () & NSS_FLAG_ADJUNCT_AS_SHADOW) == 0
271 && p != NULL /* This better should be true in all cases. */
272 && p[1] == '#' && p[2] == '#'
273 && (namelen = p - result,
274 yp_match (domain, "passwd.adjunct.byname", result, namelen,
275 &result2, &len2)) == YPERR_SUCCESS)
276 {
277 /* We found a passwd.adjunct.byname entry. Merge encrypted
278 password therein into original result. */
279 char *encrypted = strchr (result2, ':');
280 char *endp;
281 size_t restlen;
282
283 if (encrypted == NULL
284 || (endp = strchr (++encrypted, ':')) == NULL
285 || (p = strchr (p + 1, ':')) == NULL)
286 {
287 /* Invalid format of the entry. This never should happen
288 unless the data from which the NIS table is generated is
289 wrong. We simply ignore it. */
290 free (result2);
291 goto non_adjunct;
292 }
293
294 restlen = len - (p - result);
295 if (__builtin_expect ((size_t) (namelen + (endp - encrypted)
296 + restlen + 2) > buflen, 0))
297 {
298 free (result2);
299 free (result);
300 *errnop = ERANGE;
301 return NSS_STATUS_TRYAGAIN;
302 }
303
304 mempcpy (mempcpy (mempcpy (mempcpy (buffer, result, namelen),
305 ":", 1),
306 encrypted, endp - encrypted),
307 p, restlen + 1);
308 p = buffer;
309
310 free (result2);
311 }
312 else
313 {
314 non_adjunct:
315 if (__glibc_unlikely ((size_t) (len + 1) > buflen))
316 {
317 free (result);
318 *errnop = ERANGE;
319 return NSS_STATUS_TRYAGAIN;
320 }
321
322 p = buffer;
323 *((char *) mempcpy (buffer, result, len)) = '\0';
324 }
325
326 while (isspace (*p))
327 ++p;
328 if (!batch_read)
329 free (result);
330
331 parse_res = _nss_files_parse_pwent (p, pwd, (void *) buffer, buflen,
332 errnop);
333 if (__glibc_unlikely (parse_res == -1))
334 {
335 if (!batch_read)
336 free (outkey);
337 *errnop = ERANGE;
338 return NSS_STATUS_TRYAGAIN;
339 }
340
341 if (batch_read)
342 intern.offset += len + 1;
343 else
344 {
345 free (oldkey);
346 oldkey = outkey;
347 oldkeylen = keylen;
348 new_start = false;
349 }
350 }
351 while (parse_res < 1);
352
353 return NSS_STATUS_SUCCESS;
354}
355
356enum nss_status
357_nss_nis_getpwent_r (struct passwd *result, char *buffer, size_t buflen,
358 int *errnop)
359{
360 int status;
361
362 __libc_lock_lock (lock);
363
364 status = internal_nis_getpwent_r (result, buffer, buflen, errnop);
365
366 __libc_lock_unlock (lock);
367
368 return status;
369}
370
371enum nss_status
372_nss_nis_getpwnam_r (const char *name, struct passwd *pwd,
373 char *buffer, size_t buflen, int *errnop)
374{
375 if (name == NULL)
376 {
377 *errnop = EINVAL;
378 return NSS_STATUS_UNAVAIL;
379 }
380
381 char *domain;
382 if (__glibc_unlikely (yp_get_default_domain (&domain)))
383 return NSS_STATUS_UNAVAIL;
384
385 size_t namelen = strlen (name);
386
387 char *result;
388 int len;
389 int yperr = yp_match (domain, "passwd.byname", name, namelen, &result, &len);
390
391 if (__glibc_unlikely (yperr != YPERR_SUCCESS))
392 {
393 enum nss_status retval = yperr2nss (yperr);
394
395 if (retval == NSS_STATUS_TRYAGAIN)
396 *errnop = errno;
397 return retval;
398 }
399
400 /* Check for adjunct style secret passwords. They can be recognized
401 by a password starting with "##". We do not use it if the
402 passwd.adjunct.byname table is supposed to be used as a shadow.byname
403 replacement. */
404 char *result2;
405 int len2;
406 char *p = strchr (result, ':');
407 if ((_nsl_default_nss () & NSS_FLAG_ADJUNCT_AS_SHADOW) == 0
408 && p != NULL /* This better should be true in all cases. */
409 && p[1] == '#' && p[2] == '#'
410 && yp_match (domain, "passwd.adjunct.byname", name, namelen,
411 &result2, &len2) == YPERR_SUCCESS)
412 {
413 /* We found a passwd.adjunct.byname entry. Merge encrypted password
414 therein into original result. */
415 char *encrypted = strchr (result2, ':');
416 char *endp;
417
418 if (encrypted == NULL
419 || (endp = strchr (++encrypted, ':')) == NULL
420 || (p = strchr (p + 1, ':')) == NULL)
421 {
422 /* Invalid format of the entry. This never should happen
423 unless the data from which the NIS table is generated is
424 wrong. We simply ignore it. */
425 free (result2);
426 goto non_adjunct;
427 }
428
429 size_t restlen = len - (p - result);
430 if (__builtin_expect ((size_t) (namelen + (endp - encrypted)
431 + restlen + 2) > buflen, 0))
432 {
433 free (result2);
434 free (result);
435 *errnop = ERANGE;
436 return NSS_STATUS_TRYAGAIN;
437 }
438
439 __mempcpy (__mempcpy (__mempcpy (__mempcpy (buffer, name, namelen),
440 ":", 1),
441 encrypted, endp - encrypted),
442 p, restlen + 1);
443 p = buffer;
444
445 free (result2);
446 }
447 else
448 {
449 non_adjunct:
450 if (__glibc_unlikely ((size_t) (len + 1) > buflen))
451 {
452 free (result);
453 *errnop = ERANGE;
454 return NSS_STATUS_TRYAGAIN;
455 }
456
457 p = strncpy (buffer, result, len);
458 buffer[len] = '\0';
459 }
460
461 while (isspace (*p))
462 ++p;
463 free (result);
464
465 int parse_res = _nss_files_parse_pwent (p, pwd, (void *) buffer, buflen,
466 errnop);
467 if (__glibc_unlikely (parse_res < 1))
468 {
469 if (parse_res == -1)
470 return NSS_STATUS_TRYAGAIN;
471 else
472 return NSS_STATUS_NOTFOUND;
473 }
474 else
475 return NSS_STATUS_SUCCESS;
476}
477
478enum nss_status
479_nss_nis_getpwuid_r (uid_t uid, struct passwd *pwd,
480 char *buffer, size_t buflen, int *errnop)
481{
482 char *domain;
483 if (__glibc_unlikely (yp_get_default_domain (&domain)))
484 return NSS_STATUS_UNAVAIL;
485
486 char buf[32];
487 int nlen = snprintf (buf, sizeof (buf), "%lu", (unsigned long int) uid);
488
489 char *result;
490 int len;
491 int yperr = yp_match (domain, "passwd.byuid", buf, nlen, &result, &len);
492
493 if (__glibc_unlikely (yperr != YPERR_SUCCESS))
494 {
495 enum nss_status retval = yperr2nss (yperr);
496
497 if (retval == NSS_STATUS_TRYAGAIN)
498 *errnop = errno;
499 return retval;
500 }
501
502 /* Check for adjunct style secret passwords. They can be recognized
503 by a password starting with "##". We do not use it if the
504 passwd.adjunct.byname table is supposed to be used as a shadow.byname
505 replacement. */
506 char *result2;
507 int len2;
508 size_t namelen;
509 char *p = strchr (result, ':');
510 if ((_nsl_default_nss () & NSS_FLAG_ADJUNCT_AS_SHADOW) == 0
511 && p != NULL /* This better should be true in all cases. */
512 && p[1] == '#' && p[2] == '#'
513 && (namelen = p - result,
514 yp_match (domain, "passwd.adjunct.byname", result, namelen,
515 &result2, &len2)) == YPERR_SUCCESS)
516 {
517 /* We found a passwd.adjunct.byname entry. Merge encrypted password
518 therein into original result. */
519 char *encrypted = strchr (result2, ':');
520 char *endp;
521 size_t restlen;
522
523 if (encrypted == NULL
524 || (endp = strchr (++encrypted, ':')) == NULL
525 || (p = strchr (p + 1, ':')) == NULL)
526 {
527 /* Invalid format of the entry. This never should happen
528 unless the data from which the NIS table is generated is
529 wrong. We simply ignore it. */
530 free (result2);
531 goto non_adjunct;
532 }
533
534 restlen = len - (p - result);
535 if (__builtin_expect ((size_t) (namelen + (endp - encrypted)
536 + restlen + 2) > buflen, 0))
537 {
538 free (result2);
539 free (result);
540 *errnop = ERANGE;
541 return NSS_STATUS_TRYAGAIN;
542 }
543
544 __mempcpy (__mempcpy (__mempcpy (__mempcpy (buffer, result, namelen),
545 ":", 1),
546 encrypted, endp - encrypted),
547 p, restlen + 1);
548 p = buffer;
549
550 free (result2);
551 }
552 else
553 {
554 non_adjunct:
555 if (__glibc_unlikely ((size_t) (len + 1) > buflen))
556 {
557 free (result);
558 *errnop = ERANGE;
559 return NSS_STATUS_TRYAGAIN;
560 }
561
562 p = strncpy (buffer, result, len);
563 buffer[len] = '\0';
564 }
565
566 while (isspace (*p))
567 ++p;
568 free (result);
569
570 int parse_res = _nss_files_parse_pwent (p, pwd, (void *) buffer, buflen,
571 errnop);
572 if (__glibc_unlikely (parse_res < 1))
573 {
574 if (parse_res == -1)
575 return NSS_STATUS_TRYAGAIN;
576 else
577 return NSS_STATUS_NOTFOUND;
578 }
579 else
580 return NSS_STATUS_SUCCESS;
581}
582