1 /* Copyright (C) 1996-2022 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 /* Declaration of types and functions for "shadow" storage of hashed 19 passphrases. The shadow database is like the user database, but is 20 only accessible with special privileges, so that malicious users 21 cannot retrieve everyone else's hashed passphrase to brute-force at 22 their convenience. */ 23 24 #ifndef _SHADOW_H 25 #define _SHADOW_H 1 26 27 #include <features.h> 28 29 #include <paths.h> 30 31 #define __need_size_t 32 #include <stddef.h> 33 34 #include <bits/types/FILE.h> 35 36 /* Paths to the user database files. */ 37 #define SHADOW _PATH_SHADOW 38 39 40 __BEGIN_DECLS 41 42 /* A record in the shadow database. */ 43 struct spwd 44 { 45 char *sp_namp; /* Login name. */ 46 char *sp_pwdp; /* Hashed passphrase. */ 47 long int sp_lstchg; /* Date of last change. */ 48 long int sp_min; /* Minimum number of days between changes. */ 49 long int sp_max; /* Maximum number of days between changes. */ 50 long int sp_warn; /* Number of days to warn user to change 51 the password. */ 52 long int sp_inact; /* Number of days the account may be 53 inactive. */ 54 long int sp_expire; /* Number of days since 1970-01-01 until 55 account expires. */ 56 unsigned long int sp_flag; /* Reserved. */ 57 }; 58 59 60 /* Open database for reading. 61 62 This function is not part of POSIX and therefore no official 63 cancellation point. But due to similarity with an POSIX interface 64 or due to the implementation it is a cancellation point and 65 therefore not marked with __THROW. */ 66 extern void setspent (void); 67 68 /* Close database. 69 70 This function is not part of POSIX and therefore no official 71 cancellation point. But due to similarity with an POSIX interface 72 or due to the implementation it is a cancellation point and 73 therefore not marked with __THROW. */ 74 extern void endspent (void); 75 76 /* Get next entry from database, perhaps after opening the file. 77 78 This function is not part of POSIX and therefore no official 79 cancellation point. But due to similarity with an POSIX interface 80 or due to the implementation it is a cancellation point and 81 therefore not marked with __THROW. */ 82 extern struct spwd *getspent (void); 83 84 /* Get shadow entry matching NAME. 85 86 This function is not part of POSIX and therefore no official 87 cancellation point. But due to similarity with an POSIX interface 88 or due to the implementation it is a cancellation point and 89 therefore not marked with __THROW. */ 90 extern struct spwd *getspnam (const char *__name); 91 92 /* Read shadow entry from STRING. 93 94 This function is not part of POSIX and therefore no official 95 cancellation point. But due to similarity with an POSIX interface 96 or due to the implementation it is a cancellation point and 97 therefore not marked with __THROW. */ 98 extern struct spwd *sgetspent (const char *__string); 99 100 /* Read next shadow entry from STREAM. 101 102 This function is not part of POSIX and therefore no official 103 cancellation point. But due to similarity with an POSIX interface 104 or due to the implementation it is a cancellation point and 105 therefore not marked with __THROW. */ 106 extern struct spwd *fgetspent (FILE *__stream); 107 108 /* Write line containing shadow entry to stream. 109 110 This function is not part of POSIX and therefore no official 111 cancellation point. But due to similarity with an POSIX interface 112 or due to the implementation it is a cancellation point and 113 therefore not marked with __THROW. */ 114 extern int putspent (const struct spwd *__p, FILE *__stream); 115 116 117 #ifdef __USE_MISC 118 /* Reentrant versions of some of the functions above. 119 120 These functions are not part of POSIX and therefore no official 121 cancellation point. But due to similarity with an POSIX interface 122 or due to the implementation they are cancellation points and 123 therefore not marked with __THROW. */ 124 extern int getspent_r (struct spwd *__result_buf, char *__buffer, 125 size_t __buflen, struct spwd **__result) 126 __attr_access ((__write_only__, 2, 3)); 127 128 extern int getspnam_r (const char *__name, struct spwd *__result_buf, 129 char *__buffer, size_t __buflen, 130 struct spwd **__result) 131 __attr_access ((__write_only__, 3, 4)); 132 133 extern int sgetspent_r (const char *__string, struct spwd *__result_buf, 134 char *__buffer, size_t __buflen, 135 struct spwd **__result) 136 __attr_access ((__write_only__, 3, 4)); 137 138 extern int fgetspent_r (FILE *__stream, struct spwd *__result_buf, 139 char *__buffer, size_t __buflen, 140 struct spwd **__result) 141 __attr_access ((__write_only__, 3, 4)); 142 #endif /* misc */ 143 144 145 /* The simple locking functionality provided here is not suitable for 146 multi-threaded applications. */ 147 148 /* Request exclusive access to /etc/passwd and /etc/shadow. */ 149 extern int lckpwdf (void) __THROW; 150 151 /* Release exclusive access to /etc/passwd and /etc/shadow. */ 152 extern int ulckpwdf (void) __THROW; 153 154 __END_DECLS 155 156 #endif /* shadow.h */ 157