contrib/openpam/lib/pam_get_user.c

   1 /*-
   2  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
   3  * All rights reserved.
   4  *
   5  * This software was developed for the FreeBSD Project by ThinkSec AS and
   6  * Network Associates Laboratories, the Security Research Division of
   7  * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
   8  * ("CBOSS"), as part of the DARPA CHATS research program.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. The name of the author may not be used to endorse or promote
  19  *    products derived from this software without specific prior written
  20  *    permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $P4: //depot/projects/openpam/lib/pam_get_user.c#20 $
  35  */
  36
  37 #include <sys/param.h>
  38
  39 #include <stdlib.h>
  40
  41 #include <security/pam_appl.h>
  42 #include <security/openpam.h>
  43
  44 #include "openpam_impl.h"
  45
  46 static const char user_prompt[] = "Login:";
  47
  48 /*
  49  * XSSO 4.2.1
  50  * XSSO 6 page 52
  51  *
  52  * Retrieve user name
  53  */
  54
  55 int
  56 pam_get_user(pam_handle_t *pamh,
  57         const char **user,
  58         const char *prompt)
  59 {
  60         const void *promptp;
  61         char *resp;
  62         int r;
  63
  64         ENTER();
  65         if (pamh == NULL || user == NULL)
  66                 RETURNC(PAM_SYSTEM_ERR);
  67         r = pam_get_item(pamh, PAM_USER, (const void **)user);
  68         if (r == PAM_SUCCESS && *user != NULL)
  69                 RETURNC(PAM_SUCCESS);
  70         if (prompt == NULL) {
  71                 r = pam_get_item(pamh, PAM_USER_PROMPT, &promptp);
  72                 if (r != PAM_SUCCESS || promptp == NULL)
  73                         prompt = user_prompt;
  74                 else
  75                         prompt = promptp;
  76         }
  77         r = pam_prompt(pamh, PAM_PROMPT_ECHO_ON, &resp, "%s", prompt);
  78         if (r != PAM_SUCCESS)
  79                 RETURNC(r);
  80         r = pam_set_item(pamh, PAM_USER, resp);
  81         FREE(resp);
  82         if (r != PAM_SUCCESS)
  83                 RETURNC(r);
  84         r = pam_get_item(pamh, PAM_USER, (const void **)user);
  85         RETURNC(r);
  86 }
  87
  88 /*
  89  * Error codes:
  90  *
  91  *      =pam_get_item
  92  *      =pam_prompt
  93  *      =pam_set_item
  94  *      !PAM_SYMBOL_ERR
  95  */
  96
  97 /**
  98  * The =pam_get_user function returns the name of the target user, as
  99  * specified to =pam_start.
 100  * If no user was specified, nor set using =pam_set_item, =pam_get_user
 101  * will prompt for a user name.
 102  * Either way, a pointer to the user name is stored in the location
 103  * pointed to by the =user argument.
 104  *
 105  * The =prompt argument specifies a prompt to use if no user name is
 106  * cached.
 107  * If it is =NULL, the =PAM_USER_PROMPT will be used.
 108  * If that item is also =NULL, a hardcoded default prompt will be used.
 109  *
 110  * >pam_get_item
 111  * >pam_get_authtok
 112  */