1  /*
       2   * pam_localuser module
       3   *
       4   * Copyright 2001, 2004 Red Hat, Inc.
       5   * Copyright (c) 2020 Dmitry V. Levin <ldv@altlinux.org>
       6   *
       7   * Redistribution and use in source and binary forms, with or without
       8   * modification, are permitted provided that the following conditions
       9   * are met:
      10   * 1. Redistributions of source code must retain the above copyright
      11   *    notice, and the entire permission notice in its entirety,
      12   *    including the disclaimer of warranties.
      13   * 2. Redistributions in binary form must reproduce the above copyright
      14   *    notice, this list of conditions and the following disclaimer in the
      15   *    documentation and/or other materials provided with the distribution.
      16   * 3. The name of the author may not be used to endorse or promote
      17   *    products derived from this software without specific prior
      18   *    written permission.
      19   *
      20   * ALTERNATIVELY, this product may be distributed under the terms of
      21   * the GNU Public License, in which case the provisions of the GPL are
      22   * required INSTEAD OF the above restrictions.  (This clause is
      23   * necessary due to a potential bad interaction between the GPL and
      24   * the restrictions contained in a BSD-style copyright.)
      25   *
      26   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
      27   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
      28   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
      29   * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
      30   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
      31   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
      32   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
      33   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
      34   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
      35   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
      36   * OF THE POSSIBILITY OF SUCH DAMAGE.
      37   */
      38  
      39  #include "config.h"
      40  
      41  #include <stdio.h>
      42  #include <stdlib.h>
      43  #include <string.h>
      44  #include <syslog.h>
      45  #include <unistd.h>
      46  
      47  #include <security/pam_modules.h>
      48  #include <security/pam_modutil.h>
      49  #include <security/pam_ext.h>
      50  #include "pam_inline.h"
      51  
      52  int
      53  pam_sm_authenticate(pam_handle_t *pamh, int flags UNUSED,
      54  		    int argc, const char **argv)
      55  {
      56  	int i;
      57  	int rc;
      58  	int debug = 0;
      59  	const char *file_name = NULL;
      60  	const char *user_name = NULL;
      61  
      62  	/* Process arguments.  */
      63  	for (i = 0; i < argc; ++i) {
      64  		if (strcmp("debug", argv[i]) == 0) {
      65  			debug = 1;
      66  		}
      67  	}
      68  	for (i = 0; i < argc; ++i) {
      69  		const char *str;
      70  
      71  		if (strcmp("debug", argv[i]) == 0) {
      72  			/* Already processed.  */
      73  			continue;
      74  		}
      75  		if ((str = pam_str_skip_prefix(argv[i], "file=")) != NULL) {
      76  			file_name = str;
      77  			if (debug) {
      78  				pam_syslog(pamh, LOG_DEBUG,
      79  					   "set filename to %s", file_name);
      80  			}
      81  		} else {
      82  			pam_syslog(pamh, LOG_ERR, "unrecognized option: %s",
      83  				   argv[i]);
      84  		}
      85  	}
      86  
      87  	/* Obtain the user name.  */
      88  	if ((rc = pam_get_user(pamh, &user_name, NULL)) != PAM_SUCCESS) {
      89  		pam_syslog(pamh, LOG_NOTICE, "cannot determine user name: %s",
      90  			   pam_strerror(pamh, rc));
      91  		return rc == PAM_CONV_AGAIN ? PAM_INCOMPLETE : rc;
      92  	}
      93  
      94  	return pam_modutil_check_user_in_passwd(pamh, user_name, file_name);
      95  }
      96  
      97  int
      98  pam_sm_setcred(pam_handle_t *pamh UNUSED, int flags UNUSED,
      99  	       int argc UNUSED, const char **argv UNUSED)
     100  {
     101  	return PAM_SUCCESS;
     102  }
     103  
     104  int
     105  pam_sm_acct_mgmt(pam_handle_t *pamh, int flags, int argc, const char **argv)
     106  {
     107  	return pam_sm_authenticate(pamh, flags, argc, argv);
     108  }
     109  
     110  int
     111  pam_sm_open_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
     112  {
     113  	return pam_sm_authenticate(pamh, flags, argc, argv);
     114  }
     115  
     116  int
     117  pam_sm_close_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
     118  {
     119  	return pam_sm_authenticate(pamh, flags, argc, argv);
     120  }
     121  
     122  int
     123  pam_sm_chauthtok(pam_handle_t *pamh, int flags, int argc, const char **argv)
     124  {
     125  	return pam_sm_authenticate(pamh, flags, argc, argv);
     126  }