Relevant BUGIDs:

Purpose of commit: new feature

Commit summary:
---------------

2008-10-10  Thorsten Kukuk  <kukuk@thkukuk.de>

        * configure.in: add modules/pam_pwhistory/Makefile.
        * doc/sag/Linux-PAM_SAG.xml: Include pam_pwhistory.xml.
        * doc/sag/pam_pwhistory.xml: New.
        * libpam/pam_static_modules.h: Add pam_pwhistory data.
        * modules/Makefile.am: Add pam_pwhistory directory.
        * modules/pam_pwhistory/Makefile.am: New.
        * modules/pam_pwhistory/README.xml: New.
        * modules/pam_pwhistory/opasswd.c: New.
        * modules/pam_pwhistory/opasswd.h: New.
        * modules/pam_pwhistory/pam_pwhistory.8.xml: New.
        * modules/pam_pwhistory/pam_pwhistory.c: New.
        * modules/pam_pwhistory/tst-pam_pwhistory: New.
        * xtests/Makefile.am: New.
        * xtests/run-xtests.sh: New.
        * xtests/tst-pam_pwhistory1.c: New.
        * xtests/tst-pam_pwhistory1.pamd: New.
        * xtests/tst-pam_pwhistory1.sh: New.
        * po/POTFILES.in: Add modules/pam_pwhistory/.
        * po/de.po: Update translations.

1 files changed, 319 insertions, 0 deletions

diff --git a/modules/pam_pwhistory/pam_pwhistory.c b/modules/pam_pwhistory/pam_pwhistory.c
new file mode 100644
index 00000000..d3cce728
--- /dev/null
+++ b/modules/pam_pwhistory/pam_pwhistory.c
@@ -0,0 +1,319 @@
+/*
+ * Copyright (c) 2008 Thorsten Kukuk
+ * Author: Thorsten Kukuk <kukuk@suse.de>
+ *
+ * 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.
+ */
+
+#if defined(HAVE_CONFIG_H)
+#include <config.h>
+#endif
+
+#define PAM_SM_PASSWORD
+
+#include <pwd.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <shadow.h>
+#include <syslog.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <security/pam_modules.h>
+#include <security/pam_modutil.h>
+#include <security/pam_ext.h>
+#include <security/_pam_macros.h>
+
+#include "opasswd.h"
+
+#define NEW_PASSWORD_PROMPT _("New %s%spassword: ")
+#define AGAIN_PASSWORD_PROMPT _("Retype new %s%spassword: ")
+#define MISTYPED_PASSWORD _("Sorry, passwords do not match.")
+
+#define DEFAULT_BUFLEN 2048
+
+struct options_t {
+  int debug;
+  int use_authtok;
+  int enforce_for_root;
+  int remember;
+  int tries;
+};
+typedef struct options_t options_t;
+
+
+static void
+parse_option (pam_handle_t *pamh, const char *argv, options_t *options)
+{
+  if (strcasecmp (argv, "use_first_pass") == 0)
+    /* ignore */;
+  else if (strcasecmp (argv, "use_first_pass") == 0)
+    /* ignore */;
+  else if (strcasecmp (argv, "use_authtok") == 0)
+    options->use_authtok = 1;
+  else if (strcasecmp (argv, "debug") == 0)
+    options->debug = 1;
+  else if (strncasecmp (argv, "remember=", 9) == 0)
+    {
+      options->remember = strtol(&argv[9], NULL, 10);
+      if (options->remember < 0)
+        options->remember = 0;
+      if (options->remember > 400)
+        options->remember = 400;
+    }
+  else if (strncasecmp (argv, "retry=", 6) == 0)
+    {
+      options->tries = strtol(&argv[6], NULL, 10);
+      if (options->tries < 0)
+        options->tries = 1;
+    }
+  else if (strcasecmp (argv, "enforce_for_root") == 0)
+    options->enforce_for_root = 1;
+  else
+    pam_syslog (pamh, LOG_ERR, "pam_pwhistory: unknown option: %s", argv);
+}
+
+
+PAM_EXTERN int
+pam_sm_chauthtok (pam_handle_t *pamh, int flags, int argc, const char **argv)
+{
+  struct passwd *pwd;
+  char *newpass;
+  const char *user;
+  void *newpass_void;
+  int retval, tries;
+  options_t options;
+
+  memset (&options, 0, sizeof (options));
+
+  /* Set some default values, which could be overwritten later.  */
+  options.remember = 10;
+  options.tries = 1;
+
+  /* Parse parameters for module */
+  for ( ; argc-- > 0; argv++)
+    parse_option (pamh, *argv, &options);
+
+  if (options.debug)
+    pam_syslog (pamh, LOG_DEBUG, "pam_sm_chauthtok entered");
+
+
+  if (options.remember == 0)
+    return PAM_IGNORE;
+
+  retval = pam_get_user (pamh, &user, NULL);
+  if (retval != PAM_SUCCESS)
+    return retval;
+
+  if (user == NULL || strlen (user) == 0)
+    {
+      if (options.debug)
+	pam_syslog (pamh, LOG_DEBUG,
+		    "User is not known to system");
+
+      return PAM_USER_UNKNOWN;
+    }
+
+  if (flags & PAM_PRELIM_CHECK)
+    {
+      if (options.debug)
+	pam_syslog (pamh, LOG_DEBUG,
+		    "pam_sm_chauthtok(PAM_PRELIM_CHECK)");
+
+      return PAM_SUCCESS;
+    }
+
+  pwd = pam_modutil_getpwnam (pamh, user);
+  if (pwd == NULL)
+    return PAM_USER_UNKNOWN;
+
+  /* Ignore root if not enforced */
+  if (pwd->pw_uid == 0 && !options.enforce_for_root)
+    return PAM_SUCCESS;
+
+  if ((strcmp(pwd->pw_passwd, "x") == 0)  ||
+      ((pwd->pw_passwd[0] == '#') &&
+       (pwd->pw_passwd[1] == '#') &&
+       (strcmp(pwd->pw_name, pwd->pw_passwd + 2) == 0)))
+    {
+      struct spwd *spw = pam_modutil_getspnam (pamh, user);
+      if (spw == NULL)
+	return PAM_USER_UNKNOWN;
+
+      retval = save_old_password (pamh, user, pwd->pw_uid, spw->sp_pwdp,
+				  options.remember, options.debug);
+      if (retval != PAM_SUCCESS)
+	return retval;
+    }
+  else
+    {
+      retval = save_old_password (pamh, user, pwd->pw_uid, pwd->pw_passwd,
+				  options.remember, options.debug);
+      if (retval != PAM_SUCCESS)
+	return retval;
+    }
+
+  retval = pam_get_item (pamh, PAM_AUTHTOK, (const void **) &newpass_void);
+  newpass = (char *) newpass_void;
+  if (retval != PAM_SUCCESS)
+    return retval;
+  if (options.debug)
+    {
+      if (newpass)
+	pam_syslog (pamh, LOG_DEBUG, "got new auth token");
+      else
+	pam_syslog (pamh, LOG_DEBUG, "new auth token not set");
+    }
+
+  /* If we haven't been given a password yet, prompt for one... */
+  if (newpass == NULL)
+    {
+      if (options.use_authtok)
+	/* We are not allowed to ask for a new password */
+	return PAM_AUTHTOK_ERR;
+
+      tries = 0;
+
+      while ((newpass == NULL) && (tries++ < options.tries))
+	{
+	  retval = pam_prompt (pamh, PAM_PROMPT_ECHO_OFF, &newpass,
+			       NEW_PASSWORD_PROMPT, "UNIX", " ");
+	  if (retval != PAM_SUCCESS)
+	    {
+	      _pam_drop (newpass);
+	      if (retval == PAM_CONV_AGAIN)
+		retval = PAM_INCOMPLETE;
+	      return retval;
+	    }
+
+	  if (newpass == NULL)
+	    {
+	      /* We want to abort the password change */
+	      pam_error (pamh, _("Password change aborted."));
+	      return PAM_AUTHTOK_ERR;
+	    }
+
+	  if (options.debug)
+	    pam_syslog (pamh, LOG_DEBUG, "check against old password file");
+
+	  if (check_old_password (pamh, user, newpass,
+				  options.debug) != PAM_SUCCESS)
+	    {
+	      pam_error (pamh,
+			 _("Password has been already used. Choose another."));
+	      _pam_overwrite (newpass);
+	      _pam_drop (newpass);
+	      if (tries >= options.tries)
+		{
+		  if (options.debug)
+		    pam_syslog (pamh, LOG_DEBUG,
+				"Aborted, too many tries");
+		  return PAM_MAXTRIES;
+		}
+	    }
+	  else
+	    {
+	      int failed;
+	      char *new2;
+
+	      retval = pam_prompt (pamh, PAM_PROMPT_ECHO_OFF, &new2,
+				   AGAIN_PASSWORD_PROMPT, "UNIX", " ");
+              if (retval != PAM_SUCCESS)
+		return retval;
+
+              if (new2 == NULL)
+                {                       /* Aborting password change... */
+		  pam_error (pamh, _("Password change aborted."));
+                  return PAM_AUTHTOK_ERR;
+                }
+
+              failed = (strcmp (newpass, new2) != 0);
+
+              _pam_overwrite (new2);
+              _pam_drop (new2);
+
+	      if (failed)
+                {
+                  pam_error (pamh, MISTYPED_PASSWORD);
+		  _pam_overwrite (newpass);
+                  _pam_drop (newpass);
+		  if (tries >= options.tries)
+		    {
+		      if (options.debug)
+			pam_syslog (pamh, LOG_DEBUG,
+				    "Aborted, too many tries");
+		      return PAM_MAXTRIES;
+		    }
+                }
+	    }
+	}
+
+      /* Remember new password */
+      pam_set_item (pamh, PAM_AUTHTOK, (void *) newpass);
+    }
+  else /* newpass != NULL, we found an old password */
+    {
+      if (options.debug)
+        pam_syslog (pamh, LOG_DEBUG, "look in old password file");
+
+      if (check_old_password (pamh, user, newpass,
+			      options.debug) != PAM_SUCCESS)
+	{
+	  pam_error (pamh,
+		     _("Password has been already used. Choose another."));
+	  /* We are only here, because old password was set.
+             So overwrite it, else it will be stored! */
+          pam_set_item (pamh, PAM_AUTHTOK, (void *) NULL);
+
+	  return PAM_AUTHTOK_ERR;
+	}
+    }
+
+  return PAM_SUCCESS;
+}
+
+
+#ifdef PAM_STATIC
+/* static module data */
+struct pam_module _pam_pwhistory_modstruct = {
+  "pam_pwhistory",
+  NULL,
+  NULL,
+  NULL,
+  NULL,
+  NULL,
+  pam_sm_chauthtok
+};
+#endif