klibc_fixups.c

   1 /*
   2  * klibc_fixups.c - very simple implementation of stuff missing in klibc
   3  *
   4  * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
   5  * Copyright (C) 2004 Kay Sievers <kay@vrfy.org>
   6  *
   7  *      This program is free software; you can redistribute it and/or modify it
   8  *      under the terms of the GNU General Public License as published by the
   9  *      Free Software Foundation version 2 of the License.
  10  *
  11  *      This program is distributed in the hope that it will be useful, but
  12  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  *      General Public License for more details.
  15  *
  16  *      You should have received a copy of the GNU General Public License along
  17  *      with this program; if not, write to the Free Software Foundation, Inc.,
  18  *      675 Mass Ave, Cambridge, MA 02139, USA.
  19  *
  20  */
  21
  22 #ifdef __KLIBC__
  23
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <ctype.h>
  28 #include <sys/types.h>
  29
  30 #include "klibc_fixups.h"
  31 #include "logging.h"
  32
  33 #define PW_FILE         "/etc/passwd"
  34 #define GR_FILE         "/etc/group"
  35
  36 /* return the id of a passwd style line, selected by the users name */
  37 static unsigned long get_id_by_name(const char *uname, const char *dbfile)
  38 {
  39         unsigned long id = -1;
  40         FILE *file;
  41         char buf[255];
  42         char *pos;
  43         char *name;
  44         char *idstr;
  45         char *tail;
  46
  47         file = fopen(dbfile, "r");
  48         if (file == NULL) {
  49                 dbg("unable to open file '%s'", dbfile);
  50                 return -1;
  51         }
  52
  53         while (1) {
  54                 pos = fgets(buf, sizeof(buf), file);
  55                 if (pos == NULL)
  56                         break;
  57
  58                 /* get name */
  59                 name = strsep(&pos, ":");
  60                 if (name == NULL)
  61                         continue;
  62
  63                 /* skip pass */
  64                 if (strsep(&pos, ":") == NULL)
  65                         continue;
  66
  67                 /* get id */
  68                 idstr = strsep(&pos, ":");
  69                 if (idstr == NULL)
  70                         continue;
  71
  72                 if (strcmp(uname, name) == 0) {
  73                         id = strtoul(idstr, &tail, 10);
  74                         if (tail == NULL)
  75                                 id = -1;
  76                         else
  77                                 dbg("id for '%s' is '%li'", name, id);
  78                         break;
  79                 }
  80         }
  81
  82         fclose(file);
  83         return id;
  84 }
  85
  86 struct passwd *getpwnam(const char *name)
  87 {
  88         static struct passwd pw;
  89
  90         memset(&pw, 0x00, sizeof(struct passwd));
  91         pw.pw_uid = (uid_t) get_id_by_name(name, PW_FILE);
  92         if (pw.pw_uid < 0)
  93                 return NULL;
  94         else
  95                 return &pw;
  96 }
  97
  98 struct group *getgrnam(const char *name)
  99 {
 100         static struct group gr;
 101
 102         memset(&gr, 0x00, sizeof(struct group));
 103         gr.gr_gid = (gid_t) get_id_by_name(name, GR_FILE);
 104         if (gr.gr_gid < 0)
 105                 return NULL;
 106         else
 107                 return &gr;
 108 }
 109
 110 #endif