uspace/lib/posix/src/pwd.c

   1 /*
   2  * Copyright (c) 2011 Jiri Zarevucky
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /** @addtogroup libposix
  30  * @{
  31  */
  32 /** @file Password handling.
  33  */
  34
  35 #include <stdbool.h>
  36 #include <pwd.h>
  37 #include <string.h>
  38 #include <errno.h>
  39 #include <assert.h>
  40
  41 static bool entry_read = false;
  42
  43 /* dummy user account */
  44 static const struct passwd dummy_pwd = {
  45         .pw_name = (char *) "user",
  46         .pw_uid = 0,
  47         .pw_gid = 0,
  48         .pw_dir = (char *) "/",
  49         .pw_shell = (char *) "/app/bdsh"
  50 };
  51
  52 /**
  53  * Retrieve next broken-down entry from the user database.
  54  *
  55  * Since HelenOS doesn't have user accounts, this always returns
  56  * the same made-up entry.
  57  *
  58  * @return Next user database entry or NULL if not possible. Since HelenOS
  59  *     doesn't have user accounts, this always returns the same made-up entry.
  60  */
  61 struct passwd *getpwent(void)
  62 {
  63         if (entry_read) {
  64                 return NULL;
  65         }
  66
  67         entry_read = true;
  68         return (struct passwd *) &dummy_pwd;
  69 }
  70
  71 /**
  72  * Rewind the user list.
  73  */
  74 void setpwent(void)
  75 {
  76         entry_read = false;
  77 }
  78
  79 /**
  80  * Ends enumerating and releases all resources. (Noop)
  81  */
  82 void endpwent(void)
  83 {
  84         /* noop */
  85 }
  86
  87 /**
  88  * Find an entry by name.
  89  *
  90  * @param name Name of the entry.
  91  * @return Either found entry or NULL if no such entry exists.
  92  */
  93 struct passwd *getpwnam(const char *name)
  94 {
  95         assert(name != NULL);
  96
  97         if (strcmp(name, "user") != 0) {
  98                 return NULL;
  99         }
 100
 101         return (struct passwd *) &dummy_pwd;
 102 }
 103
 104 /**
 105  * Find an entry by name, thread safely.
 106  *
 107  * @param name Name of the entry.
 108  * @param pwd Original structure.
 109  * @param buffer Buffer for the strings referenced from the result structure.
 110  * @param bufsize Length of the buffer.
 111  * @param result Where to store updated structure.
 112  * @return Zero on success (either found or not found, but without an error),
 113  *     non-zero error number if error occured.
 114  */
 115 int getpwnam_r(const char *name, struct passwd *pwd,
 116     char *buffer, size_t bufsize, struct passwd **result)
 117 {
 118         assert(name != NULL);
 119         assert(pwd != NULL);
 120         assert(buffer != NULL);
 121         assert(result != NULL);
 122
 123         if (strcmp(name, "user") != 0) {
 124                 *result = NULL;
 125                 return 0;
 126         }
 127
 128         return getpwuid_r(0, pwd, buffer, bufsize, result);
 129 }
 130
 131 /**
 132  * Find an entry by UID.
 133  *
 134  * @param uid UID of the entry.
 135  * @return Either found entry or NULL if no such entry exists.
 136  */
 137 struct passwd *getpwuid(uid_t uid)
 138 {
 139         if (uid != 0) {
 140                 return NULL;
 141         }
 142
 143         return (struct passwd *) &dummy_pwd;
 144 }
 145
 146 /**
 147  * Find an entry by UID, thread safely.
 148  *
 149  * @param uid UID of the entry.
 150  * @param pwd Original structure.
 151  * @param buffer Buffer for the strings referenced from the result structure.
 152  * @param bufsize Length of the buffer.
 153  * @param result Where to store updated structure.
 154  * @return Zero on success (either found or not found, but without an error),
 155  *     non-zero error number if error occured.
 156  */
 157 int getpwuid_r(uid_t uid, struct passwd *pwd,
 158     char *buffer, size_t bufsize, struct passwd **result)
 159 {
 160         assert(pwd != NULL);
 161         assert(buffer != NULL);
 162         assert(result != NULL);
 163
 164         static const char bf[] = { 'u', 's', 'e', 'r', '\0',
 165                 '/', '\0', 'b', 'd', 's', 'h', '\0' };
 166
 167         if (uid != 0) {
 168                 *result = NULL;
 169                 return 0;
 170         }
 171         if (bufsize < sizeof(bf)) {
 172                 *result = NULL;
 173                 return ERANGE;
 174         }
 175
 176         memcpy(buffer, bf, sizeof(bf));
 177
 178         pwd->pw_name = (char *) bf;
 179         pwd->pw_uid = 0;
 180         pwd->pw_gid = 0;
 181         pwd->pw_dir = (char *) bf + 5;
 182         pwd->pw_shell = (char *) bf + 7;
 183         *result = (struct passwd *) pwd;
 184
 185         return 0;
 186 }
 187
 188 /** @}
 189  */