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diff --git a/pam_pwdfile.c b/pam_pwdfile.c
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+/* pam_pwdfile.c copyright 1999 by Charl P. Botha <cpbotha@ieee.org>
+ *
+ * $Id: pam_pwdfile.c,v 1.1.1.1 1999-08-05 13:09:07 cpbotha Exp $
+ * 
+ * pam authentication module that can be pointed at any username/crypted
+ * text file so that pam using application can use an alternate set of
+ * passwords than specified in system password database
+ *
+ * Copyright (c) Charl P. Botha, 1999. All rights reserved
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, and the entire permission notice in its entirety,
+ *    including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior
+ *    written permission.
+ * 
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions.  (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ * 
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef LINUX 
+#include <security/pam_appl.h>
+#endif  /* LINUX */
+
+#define PAM_SM_AUTH
+#include <security/pam_modules.h>
+
+#include <syslog.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define _XOPEN_SOURCE
+#include <unistd.h>
+
+/* unistd.h does not declare this as it should */
+extern char *crypt(const char *key, const char *salt);
+
+#define PWDF_PARAM "pwdfile"
+#define PWDFN_LEN 256
+#define CRYPTEDPWD_LEN 13
+
+#ifdef DEBUG
+# define D(a) a;
+#else
+# define D(a) {}
+#endif
+
+/* prototypes */
+int converse(pam_handle_t *, int, struct pam_message **, struct pam_response **);
+int _set_auth_tok(pam_handle_t *, int, int, const char **);
+
+/* logging function ripped from pam_listfile.c */
+static void _pam_log(int err, const char *format, ...)
+{
+    va_list args;
+
+    va_start(args, format);
+    openlog("pam_pwdfile", LOG_CONS|LOG_PID, LOG_AUTH);
+    vsyslog(err, format, args);
+    va_end(args);
+    closelog();
+}
+
+/* this function ripped from pam_unix/support.c */
+int converse(	pam_handle_t *pamh,
+		int nargs, 
+		struct pam_message **message,
+		struct pam_response **response	)
+
+{
+	int retval;
+	struct pam_conv *conv;
+
+	retval = pam_get_item(	pamh, PAM_CONV,  (const void **) &conv ) ; 
+	if ( retval == PAM_SUCCESS )
+		{
+	  		retval = conv->conv( 	nargs,  
+	  					( const struct pam_message ** ) message, 
+	  					response, 
+	  					conv->appdata_ptr );
+     		}
+	return retval;
+}
+
+/* this function ripped from pam_unix/support.c */
+int _set_auth_tok(	pam_handle_t *pamh, 
+			int flags, int argc, 
+			const char **argv	) {
+	int	retval;
+	char	*p;
+	
+	struct pam_message msg[1],*pmsg[1];
+	struct pam_response *resp;
+
+	/* set up conversation call */
+
+	pmsg[0] = &msg[0];
+	msg[0].msg_style = PAM_PROMPT_ECHO_OFF;
+	msg[0].msg = "Password: ";
+	resp = NULL;
+
+	if ( ( retval = converse( pamh, 1 , pmsg, &resp ) ) != PAM_SUCCESS ) 
+		return retval;
+
+	if ( resp ) 
+		{
+			if ( ( flags & PAM_DISALLOW_NULL_AUTHTOK ) && 
+							resp[0].resp == NULL ) 
+		       		{
+					free( resp );
+					return PAM_AUTH_ERR;
+		  		}
+
+			p = resp[ 0 ].resp;
+			
+			/* This could be a memory leak. If resp[0].resp 
+			   is malloc()ed, then it has to be free()ed! 
+			   	-- alex 
+			*/
+			
+		  	resp[ 0 ].resp = NULL; 		  				  
+
+	     	} 
+	else 
+		return PAM_CONV_ERR;
+
+	free( resp );
+	pam_set_item( pamh, PAM_AUTHTOK, p );
+	return PAM_SUCCESS;
+}
+
+
+/* puts the crypted password corresponding to user "name" in password,
+ * from a file with lines consisting of: name:crypted_password
+ * if unsucessful, returns 0
+ */
+static int fgetpwnam(FILE *stream, const char *name, char *password) {
+  char tempLine[256], *tpointer, *curname, *curpass, *fgr;
+  int loopdone, pwdfound;
+  
+  /* go to beginning of file */
+  rewind(stream);
+  /* some control variables */
+  loopdone = pwdfound = 0;
+  /* iterate through lines in file, until end of file */
+  do {
+    /* get the current line */
+    fgr = fgets(tempLine,256,stream);
+    /* if it's valid, go on */
+    if ( fgr != NULL) {
+      /* first get the username out */
+      tpointer = tempLine;
+      curname = strsep(&tpointer,":");
+      /* check to see if it's the right one */
+      if (strcmp(curname,name)==0) {
+	/* at least we know our loop is done */
+	loopdone = 1;
+	/* get the password and put it in its place */
+	curpass = strsep(&tpointer,":");
+	if (curpass != NULL) {
+	  strncpy(password,curpass,CRYPTEDPWD_LEN+1);
+	  pwdfound = 1;
+	} /* if (curpass... */
+      } /* if (strcmp(curname... */
+    } /* if (tempLine... */
+  } while (fgr != NULL);
+  return pwdfound;
+}
+
+/* expected hook for auth service */
+PAM_EXTERN int pam_sm_authenticate(pam_handle_t *pamh, int flags,
+				   int argc, const char **argv) {
+  int retval, pcnt, pwdfilename_found, loopdone;
+  const char *name;
+  char *password;
+  char pwdfilename[PWDFN_LEN];
+  char salt[3], crypted_password[CRYPTEDPWD_LEN+1];
+  FILE *pwdfile;
+
+  /* we require the pwdfile switch and argument to be present, else we don't work */
+  /* pcnt is the parameter counter variable for iterating through argv
+   * loopdone is an extra loop control variable */
+  pcnt = loopdone = pwdfilename_found = 0;
+  do {
+    /* see if the current parameter looks like "pwdfile" */
+    if (strcmp(argv[pcnt],PWDF_PARAM)==0) {
+      /* if argv is long enough, grab the subsequent parameter */
+      if (pcnt+1 < argc) {
+	/* make sure we can't overflow */
+	strncpy(pwdfilename,argv[pcnt+1],PWDFN_LEN);
+	/* indicate that we've found it */
+	pwdfilename_found = 1;
+      }
+      /* whether we actually found the name or not, this loop is done,
+       * as we have found the pwdfile switch itself */
+      loopdone = 1;
+    }
+  } while (!loopdone && pcnt++ < argc);
+  
+  /* for some or other reason, the password file wasn't specified */
+  if (!pwdfilename_found) {
+    _pam_log(LOG_ERR,"password file name not specified");
+    return PAM_AUTHINFO_UNAVAIL;
+  }
+  
+  /* DEBUG */
+  D(_pam_log(LOG_ERR, "password filename extracted"));
+  
+  /* now try to open the password file */
+  if ((pwdfile=fopen(pwdfilename,"r"))==NULL) {
+    _pam_log(LOG_ERR,"couldn't open password file %s",pwdfilename);
+    return PAM_AUTHINFO_UNAVAIL;
+  }
+  
+  /* get user name */
+  if ((retval = pam_get_user(pamh,&name,"login: ")) != PAM_SUCCESS) {
+    _pam_log(LOG_ERR, "username not found");
+    fclose(pwdfile);
+    return retval;
+  }
+  
+  /* DEBUG */
+  D(_pam_log(LOG_ERR,"username is %s", name));
+
+  /* get password - code from pam_unix_auth.c */
+  pam_get_item(pamh, PAM_AUTHTOK, (void *)&password);
+  if (!password) {
+    retval = _set_auth_tok(pamh, flags, argc, argv);
+    if (retval!=PAM_SUCCESS) {
+      fclose(pwdfile);
+      return retval;
+    }
+  }
+  pam_get_item(pamh, PAM_AUTHTOK, (void *)&password);
+
+  if ((retval = pam_get_item(pamh, PAM_AUTHTOK, (void *)&password)) != PAM_SUCCESS) {
+    _pam_log(LOG_ERR, "auth token not found");
+    fclose(pwdfile);
+    return retval;
+  }
+  
+  /* DEBUG */
+  D(_pam_log(LOG_ERR,"got password from user", password));
+  
+  /* now crypt password and compare to the user entry in the password file */
+  /* first make sure password is long enough -- may I do this? */
+  if (strlen(password)<2 || password==NULL) {
+    _pam_log(LOG_ERR,"password too short or NULL");
+    fclose(pwdfile);
+    return PAM_AUTH_ERR;
+  }
+  
+  /* get the crypted password corresponding to this user */
+  if (!fgetpwnam(pwdfile, name, crypted_password)) {
+    _pam_log(LOG_ERR,"password file corrupt");
+    fclose(pwdfile);
+    return PAM_AUTHINFO_UNAVAIL;
+  }
+  
+  /* DEBUG */
+  D(_pam_log(LOG_ERR,"got crypted password == %s", crypted_password));
+  
+  /* extract the salt */
+  salt[0] = crypted_password[0]; salt[1] = crypted_password[1]; salt[2] = '\0';
+  
+  /* DEBUG */
+  D(_pam_log(LOG_ERR,"user password crypted is %s", crypt(password,salt)));
+  
+  /* if things don't match up, complain */
+  crypted_password[CRYPTEDPWD_LEN] = '\0';
+  if (strcmp(crypt(password,salt),crypted_password)!=0) {
+    _pam_log(LOG_ERR,"wrong password for user %s",name);
+    fclose(pwdfile);
+    return PAM_AUTH_ERR;
+  }
+
+  /* DEBUG */
+  D(_pam_log(LOG_ERR,"passwords match"));
+  
+  /* we've gotten here, i.e. authentication was sucessful! */
+  fclose(pwdfile);
+  return PAM_SUCCESS;
+}
+
+/* another expected hook */
+PAM_EXTERN int pam_sm_setcred(pam_handle_t *pamh, int flags, 
+			      int argc, const char **argv)
+{
+    return PAM_SUCCESS;
+}
+
+#ifdef PAM_STATIC
+struct pam_module _pam_listfile_modstruct = {
+  "pam_pwdfile",
+    pam_sm_authenticate,
+    pam_sm_setcred,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+};
+#endif