1/* Copyright (C) 1996-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <ctype.h>
19#include <errno.h>
20#include <fcntl.h>
21#include <netdb.h>
22#include <nss.h>
23#include <nsswitch.h>
24#include <pwd.h>
25#include <stdio_ext.h>
26#include <string.h>
27#include <libc-lock.h>
28#include <kernel-features.h>
29#include <nss_files.h>
30
31#include "netgroup.h"
32#include "nisdomain.h"
33
34NSS_DECLARE_MODULE_FUNCTIONS (compat)
35
36static nss_action_list ni;
37static enum nss_status (*setpwent_impl) (int stayopen);
38static enum nss_status (*getpwnam_r_impl) (const char *name,
39 struct passwd * pwd, char *buffer,
40 size_t buflen, int *errnop);
41static enum nss_status (*getpwuid_r_impl) (uid_t uid, struct passwd * pwd,
42 char *buffer, size_t buflen,
43 int *errnop);
44static enum nss_status (*getpwent_r_impl) (struct passwd * pwd, char *buffer,
45 size_t buflen, int *errnop);
46static enum nss_status (*endpwent_impl) (void);
47
48/* Get the declaration of the parser function. */
49#define ENTNAME pwent
50#define STRUCTURE passwd
51#define EXTERN_PARSER
52#include <nss/nss_files/files-parse.c>
53
54/* Structure for remembering -@netgroup and -user members ... */
55#define BLACKLIST_INITIAL_SIZE 512
56#define BLACKLIST_INCREMENT 256
57struct blacklist_t
58{
59 char *data;
60 int current;
61 int size;
62};
63
64struct ent_t
65{
66 bool netgroup;
67 bool first;
68 bool files;
69 enum nss_status setent_status;
70 FILE *stream;
71 struct blacklist_t blacklist;
72 struct passwd pwd;
73 struct __netgrent netgrdata;
74};
75typedef struct ent_t ent_t;
76
77static ent_t ext_ent = { false, false, true, NSS_STATUS_SUCCESS, NULL,
78 { NULL, 0, 0 },
79 { NULL, NULL, 0, 0, NULL, NULL, NULL }};
80
81/* Protect global state against multiple changers. */
82__libc_lock_define_initialized (static, lock)
83
84/* Prototypes for local functions. */
85static void blacklist_store_name (const char *, ent_t *);
86static bool in_blacklist (const char *, int, ent_t *);
87
88/* Initialize the NSS interface/functions. The calling function must
89 hold the lock. */
90static void
91init_nss_interface (void)
92{
93 if (__nss_database_get (nss_database_passwd_compat, &ni))
94 {
95 setpwent_impl = __nss_lookup_function (ni, "setpwent");
96 getpwnam_r_impl = __nss_lookup_function (ni, "getpwnam_r");
97 getpwuid_r_impl = __nss_lookup_function (ni, "getpwuid_r");
98 getpwent_r_impl = __nss_lookup_function (ni, "getpwent_r");
99 endpwent_impl = __nss_lookup_function (ni, "endpwent");
100 }
101}
102
103static void
104give_pwd_free (struct passwd *pwd)
105{
106 free (pwd->pw_name);
107 free (pwd->pw_passwd);
108 free (pwd->pw_gecos);
109 free (pwd->pw_dir);
110 free (pwd->pw_shell);
111
112 memset (pwd, '\0', sizeof (struct passwd));
113}
114
115static size_t
116pwd_need_buflen (struct passwd *pwd)
117{
118 size_t len = 0;
119
120 if (pwd->pw_passwd != NULL)
121 len += strlen (pwd->pw_passwd) + 1;
122
123 if (pwd->pw_gecos != NULL)
124 len += strlen (pwd->pw_gecos) + 1;
125
126 if (pwd->pw_dir != NULL)
127 len += strlen (pwd->pw_dir) + 1;
128
129 if (pwd->pw_shell != NULL)
130 len += strlen (pwd->pw_shell) + 1;
131
132 return len;
133}
134
135static void
136copy_pwd_changes (struct passwd *dest, struct passwd *src,
137 char *buffer, size_t buflen)
138{
139 if (src->pw_passwd != NULL && strlen (src->pw_passwd))
140 {
141 if (buffer == NULL)
142 dest->pw_passwd = strdup (src->pw_passwd);
143 else if (dest->pw_passwd
144 && strlen (dest->pw_passwd) >= strlen (src->pw_passwd))
145 strcpy (dest->pw_passwd, src->pw_passwd);
146 else
147 {
148 dest->pw_passwd = buffer;
149 strcpy (dest->pw_passwd, src->pw_passwd);
150 buffer += strlen (dest->pw_passwd) + 1;
151 buflen = buflen - (strlen (dest->pw_passwd) + 1);
152 }
153 }
154
155 if (src->pw_gecos != NULL && strlen (src->pw_gecos))
156 {
157 if (buffer == NULL)
158 dest->pw_gecos = strdup (src->pw_gecos);
159 else if (dest->pw_gecos
160 && strlen (dest->pw_gecos) >= strlen (src->pw_gecos))
161 strcpy (dest->pw_gecos, src->pw_gecos);
162 else
163 {
164 dest->pw_gecos = buffer;
165 strcpy (dest->pw_gecos, src->pw_gecos);
166 buffer += strlen (dest->pw_gecos) + 1;
167 buflen = buflen - (strlen (dest->pw_gecos) + 1);
168 }
169 }
170 if (src->pw_dir != NULL && strlen (src->pw_dir))
171 {
172 if (buffer == NULL)
173 dest->pw_dir = strdup (src->pw_dir);
174 else if (dest->pw_dir && strlen (dest->pw_dir) >= strlen (src->pw_dir))
175 strcpy (dest->pw_dir, src->pw_dir);
176 else
177 {
178 dest->pw_dir = buffer;
179 strcpy (dest->pw_dir, src->pw_dir);
180 buffer += strlen (dest->pw_dir) + 1;
181 buflen = buflen - (strlen (dest->pw_dir) + 1);
182 }
183 }
184
185 if (src->pw_shell != NULL && strlen (src->pw_shell))
186 {
187 if (buffer == NULL)
188 dest->pw_shell = strdup (src->pw_shell);
189 else if (dest->pw_shell
190 && strlen (dest->pw_shell) >= strlen (src->pw_shell))
191 strcpy (dest->pw_shell, src->pw_shell);
192 else
193 {
194 dest->pw_shell = buffer;
195 strcpy (dest->pw_shell, src->pw_shell);
196 buffer += strlen (dest->pw_shell) + 1;
197 buflen = buflen - (strlen (dest->pw_shell) + 1);
198 }
199 }
200}
201
202static enum nss_status
203internal_setpwent (ent_t *ent, int stayopen, int needent)
204{
205 enum nss_status status = NSS_STATUS_SUCCESS;
206
207 ent->first = ent->netgroup = false;
208 ent->files = true;
209 ent->setent_status = NSS_STATUS_SUCCESS;
210
211 /* If something was left over free it. */
212 if (ent->netgroup)
213 __internal_endnetgrent (&ent->netgrdata);
214
215 if (ent->blacklist.data != NULL)
216 {
217 ent->blacklist.current = 1;
218 ent->blacklist.data[0] = '|';
219 ent->blacklist.data[1] = '\0';
220 }
221 else
222 ent->blacklist.current = 0;
223
224 if (ent->stream == NULL)
225 {
226 ent->stream = __nss_files_fopen ("/etc/passwd");
227
228 if (ent->stream == NULL)
229 status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
230 }
231 else
232 rewind (ent->stream);
233
234 give_pwd_free (&ent->pwd);
235
236 if (needent && status == NSS_STATUS_SUCCESS && setpwent_impl)
237 ent->setent_status = setpwent_impl (stayopen);
238
239 return status;
240}
241
242
243enum nss_status
244_nss_compat_setpwent (int stayopen)
245{
246 enum nss_status result;
247
248 __libc_lock_lock (lock);
249
250 if (ni == NULL)
251 init_nss_interface ();
252
253 result = internal_setpwent (&ext_ent, stayopen, 1);
254
255 __libc_lock_unlock (lock);
256
257 return result;
258}
259
260
261static enum nss_status __attribute_warn_unused_result__
262internal_endpwent (ent_t *ent)
263{
264 if (ent->stream != NULL)
265 {
266 fclose (ent->stream);
267 ent->stream = NULL;
268 }
269
270 if (ent->netgroup)
271 __internal_endnetgrent (&ent->netgrdata);
272
273 ent->first = ent->netgroup = false;
274
275 if (ent->blacklist.data != NULL)
276 {
277 ent->blacklist.current = 1;
278 ent->blacklist.data[0] = '|';
279 ent->blacklist.data[1] = '\0';
280 }
281 else
282 ent->blacklist.current = 0;
283
284 give_pwd_free (&ent->pwd);
285
286 return NSS_STATUS_SUCCESS;
287}
288
289/* Like internal_endpwent, but preserve errno in all cases. */
290static void
291internal_endpwent_noerror (ent_t *ent)
292{
293 int saved_errno = errno;
294 enum nss_status unused __attribute__ ((unused)) = internal_endpwent (ent);
295 __set_errno (saved_errno);
296}
297
298enum nss_status
299_nss_compat_endpwent (void)
300{
301 enum nss_status result;
302
303 __libc_lock_lock (lock);
304
305 if (endpwent_impl)
306 endpwent_impl ();
307
308 result = internal_endpwent (&ext_ent);
309
310 __libc_lock_unlock (lock);
311
312 return result;
313}
314
315
316static enum nss_status
317getpwent_next_nss_netgr (const char *name, struct passwd *result, ent_t *ent,
318 char *group, char *buffer, size_t buflen,
319 int *errnop)
320{
321 char *curdomain = NULL, *host, *user, *domain, *p2;
322 int status;
323 size_t p2len;
324
325 /* Leave function if NSS module does not support getpwnam_r,
326 we need this function here. */
327 if (!getpwnam_r_impl)
328 return NSS_STATUS_UNAVAIL;
329
330 if (ent->first)
331 {
332 memset (&ent->netgrdata, 0, sizeof (struct __netgrent));
333 __internal_setnetgrent (group, &ent->netgrdata);
334 ent->first = false;
335 }
336
337 while (1)
338 {
339 status = __internal_getnetgrent_r (&host, &user, &domain,
340 &ent->netgrdata, buffer, buflen,
341 errnop);
342 if (status != 1)
343 {
344 __internal_endnetgrent (&ent->netgrdata);
345 ent->netgroup = 0;
346 give_pwd_free (&ent->pwd);
347 return NSS_STATUS_RETURN;
348 }
349
350 if (user == NULL || user[0] == '-')
351 continue;
352
353 if (domain != NULL)
354 {
355 if (curdomain == NULL
356 && __nss_get_default_domain (&curdomain) != 0)
357 {
358 __internal_endnetgrent (&ent->netgrdata);
359 ent->netgroup = false;
360 give_pwd_free (&ent->pwd);
361 return NSS_STATUS_UNAVAIL;
362 }
363 if (strcmp (curdomain, domain) != 0)
364 continue;
365 }
366
367 /* If name != NULL, we are called from getpwnam. */
368 if (name != NULL)
369 if (strcmp (user, name) != 0)
370 continue;
371
372 p2len = pwd_need_buflen (&ent->pwd);
373 if (p2len > buflen)
374 {
375 *errnop = ERANGE;
376 return NSS_STATUS_TRYAGAIN;
377 }
378 p2 = buffer + (buflen - p2len);
379 buflen -= p2len;
380
381 if (getpwnam_r_impl (user, result, buffer, buflen, errnop)
382 != NSS_STATUS_SUCCESS)
383 continue;
384
385 if (!in_blacklist (result->pw_name, strlen (result->pw_name), ent))
386 {
387 /* Store the User in the blacklist for possible the "+" at the
388 end of /etc/passwd */
389 blacklist_store_name (result->pw_name, ent);
390 copy_pwd_changes (result, &ent->pwd, p2, p2len);
391 break;
392 }
393 }
394
395 return NSS_STATUS_SUCCESS;
396}
397
398/* get the next user from NSS (+ entry) */
399static enum nss_status
400getpwent_next_nss (struct passwd *result, ent_t *ent, char *buffer,
401 size_t buflen, int *errnop)
402{
403 enum nss_status status;
404 char *p2;
405 size_t p2len;
406
407 /* Return if NSS module does not support getpwent_r. */
408 if (!getpwent_r_impl)
409 return NSS_STATUS_UNAVAIL;
410
411 /* If the setpwent call failed, say so. */
412 if (ent->setent_status != NSS_STATUS_SUCCESS)
413 return ent->setent_status;
414
415 p2len = pwd_need_buflen (&ent->pwd);
416 if (p2len > buflen)
417 {
418 *errnop = ERANGE;
419 return NSS_STATUS_TRYAGAIN;
420 }
421 p2 = buffer + (buflen - p2len);
422 buflen -= p2len;
423
424 if (ent->first)
425 ent->first = false;
426
427 do
428 {
429 if ((status = getpwent_r_impl (result, buffer, buflen, errnop))
430 != NSS_STATUS_SUCCESS)
431 return status;
432 }
433 while (in_blacklist (result->pw_name, strlen (result->pw_name), ent));
434
435 copy_pwd_changes (result, &ent->pwd, p2, p2len);
436
437 return NSS_STATUS_SUCCESS;
438}
439
440/* This function handle the +user entries in /etc/passwd */
441static enum nss_status
442getpwnam_plususer (const char *name, struct passwd *result, ent_t *ent,
443 char *buffer, size_t buflen, int *errnop)
444{
445 if (!getpwnam_r_impl)
446 return NSS_STATUS_UNAVAIL;
447
448 struct passwd pwd;
449 memset (&pwd, '\0', sizeof (struct passwd));
450
451 copy_pwd_changes (&pwd, result, NULL, 0);
452
453 size_t plen = pwd_need_buflen (&pwd);
454 if (plen > buflen)
455 {
456 *errnop = ERANGE;
457 return NSS_STATUS_TRYAGAIN;
458 }
459 char *p = buffer + (buflen - plen);
460 buflen -= plen;
461
462 enum nss_status status = getpwnam_r_impl (name, result, buffer, buflen,
463 errnop);
464 if (status != NSS_STATUS_SUCCESS)
465 return status;
466
467 if (in_blacklist (result->pw_name, strlen (result->pw_name), ent))
468 return NSS_STATUS_NOTFOUND;
469
470 copy_pwd_changes (result, &pwd, p, plen);
471 give_pwd_free (&pwd);
472 /* We found the entry. */
473 return NSS_STATUS_SUCCESS;
474}
475
476static enum nss_status
477getpwent_next_file (struct passwd *result, ent_t *ent,
478 char *buffer, size_t buflen, int *errnop)
479{
480 struct parser_data *data = (void *) buffer;
481 while (1)
482 {
483 fpos_t pos;
484 char *p;
485 int parse_res;
486
487 do
488 {
489 /* We need at least 3 characters for one line. */
490 if (__glibc_unlikely (buflen < 3))
491 {
492 erange:
493 *errnop = ERANGE;
494 return NSS_STATUS_TRYAGAIN;
495 }
496
497 fgetpos (ent->stream, &pos);
498 buffer[buflen - 1] = '\xff';
499 p = fgets_unlocked (buffer, buflen, ent->stream);
500 if (p == NULL && feof_unlocked (ent->stream))
501 return NSS_STATUS_NOTFOUND;
502
503 if (p == NULL || __builtin_expect (buffer[buflen - 1] != '\xff', 0))
504 {
505 erange_reset:
506 fsetpos (ent->stream, &pos);
507 goto erange;
508 }
509
510 /* Terminate the line for any case. */
511 buffer[buflen - 1] = '\0';
512
513 /* Skip leading blanks. */
514 while (isspace (*p))
515 ++p;
516 }
517 while (*p == '\0' || *p == '#' /* Ignore empty and comment lines. */
518 /* Parse the line. If it is invalid, loop to
519 get the next line of the file to parse. */
520 || !(parse_res = _nss_files_parse_pwent (p, result, data, buflen,
521 errnop)));
522
523 if (__glibc_unlikely (parse_res == -1))
524 /* The parser ran out of space. */
525 goto erange_reset;
526
527 if (result->pw_name[0] != '+' && result->pw_name[0] != '-')
528 /* This is a real entry. */
529 break;
530
531 /* -@netgroup */
532 if (result->pw_name[0] == '-' && result->pw_name[1] == '@'
533 && result->pw_name[2] != '\0')
534 {
535 /* XXX Do not use fixed length buffer. */
536 char buf2[1024];
537 char *user, *host, *domain;
538 struct __netgrent netgrdata;
539
540 memset (&netgrdata, 0, sizeof (struct __netgrent));
541 __internal_setnetgrent (&result->pw_name[2], &netgrdata);
542 while (__internal_getnetgrent_r (&host, &user, &domain, &netgrdata,
543 buf2, sizeof (buf2), errnop))
544 {
545 if (user != NULL && user[0] != '-')
546 blacklist_store_name (user, ent);
547 }
548 __internal_endnetgrent (&netgrdata);
549 continue;
550 }
551
552 /* +@netgroup */
553 if (result->pw_name[0] == '+' && result->pw_name[1] == '@'
554 && result->pw_name[2] != '\0')
555 {
556 enum nss_status status;
557
558 ent->netgroup = true;
559 ent->first = true;
560 copy_pwd_changes (&ent->pwd, result, NULL, 0);
561
562 status = getpwent_next_nss_netgr (NULL, result, ent,
563 &result->pw_name[2],
564 buffer, buflen, errnop);
565 if (status == NSS_STATUS_RETURN)
566 continue;
567 else
568 return status;
569 }
570
571 /* -user */
572 if (result->pw_name[0] == '-' && result->pw_name[1] != '\0'
573 && result->pw_name[1] != '@')
574 {
575 blacklist_store_name (&result->pw_name[1], ent);
576 continue;
577 }
578
579 /* +user */
580 if (result->pw_name[0] == '+' && result->pw_name[1] != '\0'
581 && result->pw_name[1] != '@')
582 {
583 size_t len = strlen (result->pw_name);
584 char buf[len];
585 enum nss_status status;
586
587 /* Store the User in the blacklist for the "+" at the end of
588 /etc/passwd */
589 memcpy (buf, &result->pw_name[1], len);
590 status = getpwnam_plususer (&result->pw_name[1], result, ent,
591 buffer, buflen, errnop);
592 blacklist_store_name (buf, ent);
593
594 if (status == NSS_STATUS_SUCCESS) /* We found the entry. */
595 break;
596 else if (status == NSS_STATUS_RETURN /* We couldn't parse the entry */
597 || status == NSS_STATUS_NOTFOUND) /* entry doesn't exist */
598 continue;
599 else
600 {
601 if (status == NSS_STATUS_TRYAGAIN)
602 {
603 /* The parser ran out of space */
604 fsetpos (ent->stream, &pos);
605 *errnop = ERANGE;
606 }
607 return status;
608 }
609 }
610
611 /* +:... */
612 if (result->pw_name[0] == '+' && result->pw_name[1] == '\0')
613 {
614 ent->files = false;
615 ent->first = true;
616 copy_pwd_changes (&ent->pwd, result, NULL, 0);
617
618 return getpwent_next_nss (result, ent, buffer, buflen, errnop);
619 }
620 }
621
622 return NSS_STATUS_SUCCESS;
623}
624
625
626static enum nss_status
627internal_getpwent_r (struct passwd *pw, ent_t *ent, char *buffer,
628 size_t buflen, int *errnop)
629{
630 if (ent->netgroup)
631 {
632 enum nss_status status;
633
634 /* We are searching members in a netgroup */
635 /* Since this is not the first call, we don't need the group name */
636 status = getpwent_next_nss_netgr (NULL, pw, ent, NULL, buffer, buflen,
637 errnop);
638 if (status == NSS_STATUS_RETURN)
639 return getpwent_next_file (pw, ent, buffer, buflen, errnop);
640 else
641 return status;
642 }
643 else if (ent->files)
644 return getpwent_next_file (pw, ent, buffer, buflen, errnop);
645 else
646 return getpwent_next_nss (pw, ent, buffer, buflen, errnop);
647
648}
649
650enum nss_status
651_nss_compat_getpwent_r (struct passwd *pwd, char *buffer, size_t buflen,
652 int *errnop)
653{
654 enum nss_status result = NSS_STATUS_SUCCESS;
655
656 __libc_lock_lock (lock);
657
658 /* Be prepared that the setpwent function was not called before. */
659 if (ni == NULL)
660 init_nss_interface ();
661
662 if (ext_ent.stream == NULL)
663 result = internal_setpwent (&ext_ent, 1, 1);
664
665 if (result == NSS_STATUS_SUCCESS)
666 result = internal_getpwent_r (pwd, &ext_ent, buffer, buflen, errnop);
667
668 __libc_lock_unlock (lock);
669
670 return result;
671}
672
673/* Searches in /etc/passwd and the NIS/NIS+ map for a special user */
674static enum nss_status
675internal_getpwnam_r (const char *name, struct passwd *result, ent_t *ent,
676 char *buffer, size_t buflen, int *errnop)
677{
678 struct parser_data *data = (void *) buffer;
679
680 while (1)
681 {
682 fpos_t pos;
683 char *p;
684 int parse_res;
685
686 do
687 {
688 /* We need at least 3 characters for one line. */
689 if (__glibc_unlikely (buflen < 3))
690 {
691 erange:
692 *errnop = ERANGE;
693 return NSS_STATUS_TRYAGAIN;
694 }
695
696 fgetpos (ent->stream, &pos);
697 buffer[buflen - 1] = '\xff';
698 p = fgets_unlocked (buffer, buflen, ent->stream);
699 if (p == NULL && feof_unlocked (ent->stream))
700 {
701 return NSS_STATUS_NOTFOUND;
702 }
703 if (p == NULL || __builtin_expect (buffer[buflen - 1] != '\xff', 0))
704 {
705 erange_reset:
706 fsetpos (ent->stream, &pos);
707 goto erange;
708 }
709
710 /* Terminate the line for any case. */
711 buffer[buflen - 1] = '\0';
712
713 /* Skip leading blanks. */
714 while (isspace (*p))
715 ++p;
716 }
717 while (*p == '\0' || *p == '#' /* Ignore empty and comment lines. */
718 /* Parse the line. If it is invalid, loop to
719 get the next line of the file to parse. */
720 || !(parse_res = _nss_files_parse_pwent (p, result, data, buflen,
721 errnop)));
722
723 if (__glibc_unlikely (parse_res == -1))
724 /* The parser ran out of space. */
725 goto erange_reset;
726
727 /* This is a real entry. */
728 if (result->pw_name[0] != '+' && result->pw_name[0] != '-')
729 {
730 if (strcmp (result->pw_name, name) == 0)
731 return NSS_STATUS_SUCCESS;
732 else
733 continue;
734 }
735
736 /* -@netgroup */
737 if (result->pw_name[0] == '-' && result->pw_name[1] == '@'
738 && result->pw_name[2] != '\0')
739 {
740 if (innetgr (&result->pw_name[2], NULL, name, NULL))
741 return NSS_STATUS_NOTFOUND;
742 continue;
743 }
744
745 /* +@netgroup */
746 if (result->pw_name[0] == '+' && result->pw_name[1] == '@'
747 && result->pw_name[2] != '\0')
748 {
749 enum nss_status status;
750
751 if (innetgr (&result->pw_name[2], NULL, name, NULL))
752 {
753 status = getpwnam_plususer (name, result, ent, buffer,
754 buflen, errnop);
755
756 if (status == NSS_STATUS_RETURN)
757 continue;
758
759 return status;
760 }
761 continue;
762 }
763
764 /* -user */
765 if (result->pw_name[0] == '-' && result->pw_name[1] != '\0'
766 && result->pw_name[1] != '@')
767 {
768 if (strcmp (&result->pw_name[1], name) == 0)
769 return NSS_STATUS_NOTFOUND;
770 else
771 continue;
772 }
773
774 /* +user */
775 if (result->pw_name[0] == '+' && result->pw_name[1] != '\0'
776 && result->pw_name[1] != '@')
777 {
778 if (strcmp (name, &result->pw_name[1]) == 0)
779 {
780 enum nss_status status;
781
782 status = getpwnam_plususer (name, result, ent, buffer, buflen,
783 errnop);
784 if (status == NSS_STATUS_RETURN)
785 /* We couldn't parse the entry */
786 return NSS_STATUS_NOTFOUND;
787 else
788 return status;
789 }
790 }
791
792 /* +:... */
793 if (result->pw_name[0] == '+' && result->pw_name[1] == '\0')
794 {
795 enum nss_status status;
796
797 status = getpwnam_plususer (name, result, ent,
798 buffer, buflen, errnop);
799 if (status == NSS_STATUS_SUCCESS) /* We found the entry. */
800 break;
801 else if (status == NSS_STATUS_RETURN) /* We couldn't parse the entry */
802 return NSS_STATUS_NOTFOUND;
803 else
804 return status;
805 }
806 }
807 return NSS_STATUS_SUCCESS;
808}
809
810enum nss_status
811_nss_compat_getpwnam_r (const char *name, struct passwd *pwd,
812 char *buffer, size_t buflen, int *errnop)
813{
814 enum nss_status result;
815 ent_t ent = { false, false, true, NSS_STATUS_SUCCESS, NULL, { NULL, 0, 0 },
816 { NULL, NULL, 0, 0, NULL, NULL, NULL }};
817
818 if (name[0] == '-' || name[0] == '+')
819 return NSS_STATUS_NOTFOUND;
820
821 __libc_lock_lock (lock);
822
823 if (ni == NULL)
824 init_nss_interface ();
825
826 __libc_lock_unlock (lock);
827
828 result = internal_setpwent (&ent, 0, 0);
829
830 if (result == NSS_STATUS_SUCCESS)
831 result = internal_getpwnam_r (name, pwd, &ent, buffer, buflen, errnop);
832
833 internal_endpwent_noerror (&ent);
834
835 return result;
836}
837
838/* This function handle the + entry in /etc/passwd for getpwuid */
839static enum nss_status
840getpwuid_plususer (uid_t uid, struct passwd *result, char *buffer,
841 size_t buflen, int *errnop)
842{
843 struct passwd pwd;
844 char *p;
845 size_t plen;
846
847 if (!getpwuid_r_impl)
848 return NSS_STATUS_UNAVAIL;
849
850 memset (&pwd, '\0', sizeof (struct passwd));
851
852 copy_pwd_changes (&pwd, result, NULL, 0);
853
854 plen = pwd_need_buflen (&pwd);
855 if (plen > buflen)
856 {
857 *errnop = ERANGE;
858 return NSS_STATUS_TRYAGAIN;
859 }
860 p = buffer + (buflen - plen);
861 buflen -= plen;
862
863 if (getpwuid_r_impl (uid, result, buffer, buflen, errnop) ==
864 NSS_STATUS_SUCCESS)
865 {
866 copy_pwd_changes (result, &pwd, p, plen);
867 give_pwd_free (&pwd);
868 /* We found the entry. */
869 return NSS_STATUS_SUCCESS;
870 }
871 else
872 {
873 /* Give buffer the old len back */
874 buflen += plen;
875 give_pwd_free (&pwd);
876 }
877 return NSS_STATUS_RETURN;
878}
879
880/* Searches in /etc/passwd and the NSS subsystem for a special user id */
881static enum nss_status
882internal_getpwuid_r (uid_t uid, struct passwd *result, ent_t *ent,
883 char *buffer, size_t buflen, int *errnop)
884{
885 struct parser_data *data = (void *) buffer;
886
887 while (1)
888 {
889 fpos_t pos;
890 char *p;
891 int parse_res;
892
893 do
894 {
895 /* We need at least 3 characters for one line. */
896 if (__glibc_unlikely (buflen < 3))
897 {
898 erange:
899 *errnop = ERANGE;
900 return NSS_STATUS_TRYAGAIN;
901 }
902
903 fgetpos (ent->stream, &pos);
904 buffer[buflen - 1] = '\xff';
905 p = fgets_unlocked (buffer, buflen, ent->stream);
906 if (p == NULL && feof_unlocked (ent->stream))
907 return NSS_STATUS_NOTFOUND;
908
909 if (p == NULL || __builtin_expect (buffer[buflen - 1] != '\xff', 0))
910 {
911 erange_reset:
912 fsetpos (ent->stream, &pos);
913 goto erange;
914 }
915
916 /* Terminate the line for any case. */
917 buffer[buflen - 1] = '\0';
918
919 /* Skip leading blanks. */
920 while (isspace (*p))
921 ++p;
922 }
923 while (*p == '\0' || *p == '#' /* Ignore empty and comment lines. */
924 /* Parse the line. If it is invalid, loop to
925 get the next line of the file to parse. */
926 || !(parse_res = _nss_files_parse_pwent (p, result, data, buflen,
927 errnop)));
928
929 if (__glibc_unlikely (parse_res == -1))
930 /* The parser ran out of space. */
931 goto erange_reset;
932
933 /* This is a real entry. */
934 if (result->pw_name[0] != '+' && result->pw_name[0] != '-')
935 {
936 if (result->pw_uid == uid)
937 return NSS_STATUS_SUCCESS;
938 else
939 continue;
940 }
941
942 /* -@netgroup */
943 if (result->pw_name[0] == '-' && result->pw_name[1] == '@'
944 && result->pw_name[2] != '\0')
945 {
946 /* -1, because we remove first two character of pw_name. */
947 size_t len = strlen (result->pw_name) - 1;
948 char buf[len];
949 enum nss_status status;
950
951 memcpy (buf, &result->pw_name[2], len);
952
953 status = getpwuid_plususer (uid, result, buffer, buflen, errnop);
954 if (status == NSS_STATUS_SUCCESS
955 && innetgr (buf, NULL, result->pw_name, NULL))
956 return NSS_STATUS_NOTFOUND;
957
958 continue;
959 }
960
961 /* +@netgroup */
962 if (result->pw_name[0] == '+' && result->pw_name[1] == '@'
963 && result->pw_name[2] != '\0')
964 {
965 /* -1, because we remove first two characters of pw_name. */
966 size_t len = strlen (result->pw_name) - 1;
967 char buf[len];
968 enum nss_status status;
969
970 memcpy (buf, &result->pw_name[2], len);
971
972 status = getpwuid_plususer (uid, result, buffer, buflen, errnop);
973
974 if (status == NSS_STATUS_RETURN)
975 continue;
976
977 if (status == NSS_STATUS_SUCCESS)
978 {
979 if (innetgr (buf, NULL, result->pw_name, NULL))
980 return NSS_STATUS_SUCCESS;
981 }
982 else if (status == NSS_STATUS_RETURN) /* We couldn't parse the entry */
983 return NSS_STATUS_NOTFOUND;
984 else
985 return status;
986
987 continue;
988 }
989
990 /* -user */
991 if (result->pw_name[0] == '-' && result->pw_name[1] != '\0'
992 && result->pw_name[1] != '@')
993 {
994 size_t len = strlen (result->pw_name);
995 char buf[len];
996 enum nss_status status;
997
998 memcpy (buf, &result->pw_name[1], len);
999
1000 status = getpwuid_plususer (uid, result, buffer, buflen, errnop);
1001 if (status == NSS_STATUS_SUCCESS
1002 && innetgr (buf, NULL, result->pw_name, NULL))
1003 return NSS_STATUS_NOTFOUND;
1004 continue;
1005 }
1006
1007 /* +user */
1008 if (result->pw_name[0] == '+' && result->pw_name[1] != '\0'
1009 && result->pw_name[1] != '@')
1010 {
1011 size_t len = strlen (result->pw_name);
1012 char buf[len];
1013 enum nss_status status;
1014
1015 memcpy (buf, &result->pw_name[1], len);
1016
1017 status = getpwuid_plususer (uid, result, buffer, buflen, errnop);
1018
1019 if (status == NSS_STATUS_RETURN)
1020 continue;
1021
1022 if (status == NSS_STATUS_SUCCESS)
1023 {
1024 if (strcmp (buf, result->pw_name) == 0)
1025 return NSS_STATUS_SUCCESS;
1026 }
1027 else if (status == NSS_STATUS_RETURN) /* We couldn't parse the entry */
1028 return NSS_STATUS_NOTFOUND;
1029 else
1030 return status;
1031
1032 continue;
1033 }
1034
1035 /* +:... */
1036 if (result->pw_name[0] == '+' && result->pw_name[1] == '\0')
1037 {
1038 enum nss_status status;
1039
1040 status = getpwuid_plususer (uid, result, buffer, buflen, errnop);
1041 if (status == NSS_STATUS_SUCCESS) /* We found the entry. */
1042 break;
1043 else if (status == NSS_STATUS_RETURN) /* We couldn't parse the entry */
1044 return NSS_STATUS_NOTFOUND;
1045 else
1046 return status;
1047 }
1048 }
1049 return NSS_STATUS_SUCCESS;
1050}
1051
1052enum nss_status
1053_nss_compat_getpwuid_r (uid_t uid, struct passwd *pwd,
1054 char *buffer, size_t buflen, int *errnop)
1055{
1056 enum nss_status result;
1057 ent_t ent = { false, false, true, NSS_STATUS_SUCCESS, NULL, { NULL, 0, 0 },
1058 { NULL, NULL, 0, 0, NULL, NULL, NULL }};
1059
1060 __libc_lock_lock (lock);
1061
1062 if (ni == NULL)
1063 init_nss_interface ();
1064
1065 __libc_lock_unlock (lock);
1066
1067 result = internal_setpwent (&ent, 0, 0);
1068
1069 if (result == NSS_STATUS_SUCCESS)
1070 result = internal_getpwuid_r (uid, pwd, &ent, buffer, buflen, errnop);
1071
1072 internal_endpwent_noerror (&ent);
1073
1074 return result;
1075}
1076
1077
1078/* Support routines for remembering -@netgroup and -user entries.
1079 The names are stored in a single string with `|' as separator. */
1080static void
1081blacklist_store_name (const char *name, ent_t *ent)
1082{
1083 int namelen = strlen (name);
1084 char *tmp;
1085
1086 /* first call, setup cache */
1087 if (ent->blacklist.size == 0)
1088 {
1089 ent->blacklist.size = MAX (BLACKLIST_INITIAL_SIZE, 2 * namelen);
1090 ent->blacklist.data = malloc (ent->blacklist.size);
1091 if (ent->blacklist.data == NULL)
1092 return;
1093 ent->blacklist.data[0] = '|';
1094 ent->blacklist.data[1] = '\0';
1095 ent->blacklist.current = 1;
1096 }
1097 else
1098 {
1099 if (in_blacklist (name, namelen, ent))
1100 return; /* no duplicates */
1101
1102 if (ent->blacklist.current + namelen + 1 >= ent->blacklist.size)
1103 {
1104 ent->blacklist.size += MAX (BLACKLIST_INCREMENT, 2 * namelen);
1105 tmp = realloc (ent->blacklist.data, ent->blacklist.size);
1106 if (tmp == NULL)
1107 {
1108 free (ent->blacklist.data);
1109 ent->blacklist.size = 0;
1110 return;
1111 }
1112 ent->blacklist.data = tmp;
1113 }
1114 }
1115
1116 tmp = stpcpy (ent->blacklist.data + ent->blacklist.current, name);
1117 *tmp++ = '|';
1118 *tmp = '\0';
1119 ent->blacklist.current += namelen + 1;
1120
1121 return;
1122}
1123
1124/* Returns whether ent->blacklist contains name. */
1125static bool
1126in_blacklist (const char *name, int namelen, ent_t *ent)
1127{
1128 char buf[namelen + 3];
1129 char *cp;
1130
1131 if (ent->blacklist.data == NULL)
1132 return false;
1133
1134 buf[0] = '|';
1135 cp = stpcpy (&buf[1], name);
1136 *cp++ = '|';
1137 *cp = '\0';
1138 return strstr (ent->blacklist.data, buf) != NULL;
1139}
1140