| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame^] | 1 | /* Copyright (C) 1996-2015 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 | <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include <ctype.h> |
| 19 | #include <errno.h> |
| 20 | #include <stdio.h> |
| 21 | #include <stdio_ext.h> |
| 22 | #include <stdlib.h> |
| 23 | #include <string.h> |
| 24 | #include <bits/libc-lock.h> |
| 25 | |
| 26 | #include <libnsl.h> |
| 27 | |
| 28 | |
| 29 | /* Path of the file. */ |
| 30 | static const char default_nss[] = "/etc/default/nss"; |
| 31 | |
| 32 | /* Flags once read from the file. */ |
| 33 | static int default_nss_flags; |
| 34 | |
| 35 | /* Code to make sure we call 'init' once. */ |
| 36 | __libc_once_define (static, once); |
| 37 | |
| 38 | /* Table of the recognized variables. */ |
| 39 | static const struct |
| 40 | { |
| 41 | char name[23]; |
| 42 | unsigned int len; |
| 43 | int flag; |
| 44 | } vars[] = |
| 45 | { |
| 46 | #define STRNLEN(s) s, sizeof (s) - 1 |
| 47 | { STRNLEN ("NETID_AUTHORITATIVE"), NSS_FLAG_NETID_AUTHORITATIVE }, |
| 48 | { STRNLEN ("SERVICES_AUTHORITATIVE"), NSS_FLAG_SERVICES_AUTHORITATIVE }, |
| 49 | { STRNLEN ("SETENT_BATCH_READ"), NSS_FLAG_SETENT_BATCH_READ }, |
| 50 | { STRNLEN ("ADJUNCT_AS_SHADOW"), NSS_FLAG_ADJUNCT_AS_SHADOW }, |
| 51 | }; |
| 52 | #define nvars (sizeof (vars) / sizeof (vars[0])) |
| 53 | |
| 54 | |
| 55 | static void |
| 56 | init (void) |
| 57 | { |
| 58 | int saved_errno = errno; |
| 59 | FILE *fp = fopen (default_nss, "rce"); |
| 60 | if (fp != NULL) |
| 61 | { |
| 62 | char *line = NULL; |
| 63 | size_t linelen = 0; |
| 64 | |
| 65 | __fsetlocking (fp, FSETLOCKING_BYCALLER); |
| 66 | |
| 67 | while (!feof_unlocked (fp)) |
| 68 | { |
| 69 | ssize_t n = getline (&line, &linelen, fp); |
| 70 | if (n <= 0) |
| 71 | break; |
| 72 | |
| 73 | /* Recognize only |
| 74 | |
| 75 | <THE-VARIABLE> = TRUE |
| 76 | |
| 77 | with arbitrary white spaces. */ |
| 78 | char *cp = line; |
| 79 | while (isspace (*cp)) |
| 80 | ++cp; |
| 81 | |
| 82 | /* Recognize comment lines. */ |
| 83 | if (*cp == '#') |
| 84 | continue; |
| 85 | |
| 86 | int idx; |
| 87 | for (idx = 0; idx < nvars; ++idx) |
| 88 | if (strncmp (cp, vars[idx].name, vars[idx].len) == 0) |
| 89 | break; |
| 90 | if (idx == nvars) |
| 91 | continue; |
| 92 | |
| 93 | cp += vars[idx].len; |
| 94 | while (isspace (*cp)) |
| 95 | ++cp; |
| 96 | if (*cp++ != '=') |
| 97 | continue; |
| 98 | while (isspace (*cp)) |
| 99 | ++cp; |
| 100 | |
| 101 | if (strncmp (cp, "TRUE", 4) != 0) |
| 102 | continue; |
| 103 | cp += 4; |
| 104 | |
| 105 | while (isspace (*cp)) |
| 106 | ++cp; |
| 107 | |
| 108 | if (*cp == '\0') |
| 109 | default_nss_flags |= vars[idx].flag; |
| 110 | } |
| 111 | |
| 112 | free (line); |
| 113 | |
| 114 | fclose (fp); |
| 115 | } |
| 116 | __set_errno (saved_errno); |
| 117 | } |
| 118 | |
| 119 | |
| 120 | int |
| 121 | _nsl_default_nss (void) |
| 122 | { |
| 123 | /* If we have not yet read the file yet do it now. */ |
| 124 | __libc_once (once, init); |
| 125 | |
| 126 | return default_nss_flags; |
| 127 | } |