lib/roken/getusershell.c

   1 /*
   2  * Copyright (c) 1985, 1993
   3  *      The Regents of the University of California.  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  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include <config.h>
  31
  32 #ifndef HAVE_GETUSERSHELL
  33
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37 #include <ctype.h>
  38 #ifdef HAVE_PATHS_H
  39 #include <paths.h>
  40 #endif
  41 #ifdef HAVE_SYS_TYPES_H
  42 #include <sys/types.h>
  43 #endif
  44 #ifdef HAVE_SYS_STAT_H
  45 #include <sys/stat.h>
  46 #endif
  47 #ifdef HAVE_SYS_PARAM_H
  48 #include <sys/param.h>
  49 #endif
  50
  51 #ifdef HAVE_USERSEC_H
  52 struct aud_rec;
  53 #include <usersec.h>
  54 #endif
  55 #ifdef HAVE_USERCONF_H
  56 #include <userconf.h>
  57 #endif
  58 #include "roken.h"
  59
  60 #ifndef _PATH_SHELLS
  61 #define _PATH_SHELLS "/etc/shells"
  62 #endif
  63
  64 #ifndef _PATH_BSHELL
  65 #define _PATH_BSHELL "/bin/sh"
  66 #endif
  67
  68 #ifndef _PATH_CSHELL
  69 #define _PATH_CSHELL "/bin/csh"
  70 #endif
  71
  72 /*
  73  * Local shells should NOT be added here.  They should be added in
  74  * /etc/shells.
  75  */
  76
  77 static char *okshells[] = { _PATH_BSHELL, _PATH_CSHELL, NULL };
  78 static char **curshell, **shells, *strings;
  79 static char **initshells (void);
  80
  81 /*
  82  * Get a list of shells from _PATH_SHELLS, if it exists.
  83  */
  84 char * ROKEN_LIB_FUNCTION
  85 getusershell()
  86 {
  87     char *ret;
  88
  89     if (curshell == NULL)
  90         curshell = initshells();
  91     ret = *curshell;
  92     if (ret != NULL)
  93         curshell++;
  94     return (ret);
  95 }
  96
  97 void ROKEN_LIB_FUNCTION
  98 endusershell()
  99 {
 100     if (shells != NULL)
 101         free(shells);
 102     shells = NULL;
 103     if (strings != NULL)
 104         free(strings);
 105     strings = NULL;
 106     curshell = NULL;
 107 }
 108
 109 void ROKEN_LIB_FUNCTION
 110 setusershell()
 111 {
 112     curshell = initshells();
 113 }
 114
 115 static char **
 116 initshells()
 117 {
 118     char **sp, *cp;
 119 #ifdef HAVE_GETCONFATTR
 120     char *tmp;
 121     int nsh;
 122 #else
 123     FILE *fp;
 124 #endif
 125     struct stat statb;
 126
 127     free(shells);
 128     shells = NULL;
 129     free(strings);
 130     strings = NULL;
 131 #ifdef HAVE_GETCONFATTR
 132     if(getconfattr(SC_SYS_LOGIN, SC_SHELLS, &tmp, SEC_LIST) != 0)
 133         return okshells;
 134
 135     for(cp = tmp, nsh = 0; *cp; cp += strlen(cp) + 1, nsh++);
 136
 137     shells = calloc(nsh + 1, sizeof(*shells));
 138     if(shells == NULL)
 139         return okshells;
 140
 141     strings = malloc(cp - tmp);
 142     if(strings == NULL) {
 143         free(shells);
 144         shells = NULL;
 145         return okshells;
 146     }
 147     memcpy(strings, tmp, cp - tmp);
 148     for(sp = shells, cp = strings; *cp; cp += strlen(cp) + 1, sp++)
 149         *sp = cp;
 150 #else
 151     if ((fp = fopen(_PATH_SHELLS, "r")) == NULL)
 152         return (okshells);
 153     if (fstat(fileno(fp), &statb) == -1) {
 154         fclose(fp);
 155         return (okshells);
 156     }
 157     if ((strings = malloc((u_int)statb.st_size)) == NULL) {
 158         fclose(fp);
 159         return (okshells);
 160     }
 161     shells = calloc((unsigned)statb.st_size / 3, sizeof (char *));
 162     if (shells == NULL) {
 163         fclose(fp);
 164         free(strings);
 165         strings = NULL;
 166         return (okshells);
 167     }
 168     sp = shells;
 169     cp = strings;
 170     while (fgets(cp, MaxPathLen + 1, fp) != NULL) {
 171         while (*cp != '#' && *cp != '/' && *cp != '\0')
 172             cp++;
 173         if (*cp == '#' || *cp == '\0')
 174             continue;
 175         *sp++ = cp;
 176         while (!isspace((unsigned char)*cp) && *cp != '#' && *cp != '\0')
 177             cp++;
 178         *cp++ = '\0';
 179     }
 180     fclose(fp);
 181 #endif
 182     *sp = NULL;
 183     return (shells);
 184 }
 185 #endif /* HAVE_GETUSERSHELL */