Index: includes/passwordhash.inc
===================================================================
RCS file: includes/passwordhash.inc
diff -N includes/passwordhash.inc
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ includes/passwordhash.inc	23 Feb 2008 00:33:04 -0000
@@ -0,0 +1,198 @@
+<?php
+// $Id$
+
+/**
+ * @file
+ * Secure password hashing functions for user authentication.
+ *
+ * Based on the Portable PHP password hashing framework, Version 0.1.
+ * @see http://www.openwall.com/phpass/
+ */
+
+/**
+ * The standard log2 number of iterations for password stretching. This should
+ * probably be increased by 1 at least every other Drupal version.
+ */
+define('DRUPAL_HASH_ITERATION', 14);
+
+/**
+ * Returns a string for mapping an int to the corresponding base 64 character.
+ */ 
+function _passwordhash_itoa64() {
+  return './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
+}
+
+/**
+ * Returns a string of highly randomized bytes (over the full 8-bit range)
+ * 
+ * @param $count
+ *   The number of characters (bytes) to return in the string.
+ */
+function _passwordhash_random_bytes($count)  {
+  return substr(hash('sha256', uniqid(mt_rand(), TRUE)) . md5(uniqid(mt_rand(), TRUE), TRUE), 0, $count);
+}
+
+/**
+ * Encodes bytes into printable base 64, up to a set number of bytes.
+ * 
+ * @param $input
+ *   The string containing bytes to encode.
+ * @param $count
+ *   The number of characters (bytes) to encode.
+ *
+ * @return
+ *   Encoded string 
+ */
+function  _passwordhash_encode64($input, $count)  {
+  $output = '';
+  $i = 0;
+  $itoa64 = _passwordhash_itoa64();
+  do {
+    $value = ord($input[$i++]);
+    $output .= $itoa64[$value & 0x3f];
+    if ($i < $count) {
+      $value |= ord($input[$i]) << 8;
+    }
+    $output .= $itoa64[($value >> 6) & 0x3f];
+    if ($i++ >= $count) {
+      break;
+    }
+    if ($i < $count) {
+      $value |= ord($input[$i]) << 16;
+    }
+    $output .= $itoa64[($value >> 12) & 0x3f];
+    if ($i++ >= $count) {
+      break;
+    }
+    $output .= $itoa64[($value >> 18) & 0x3f];
+  } while ($i < $count);
+
+  return $output;
+}
+
+/**
+ * Generates a random base 64 encoded salt prefixed with settings for the hash.
+ *
+ * @param $iteration_count_log2
+ *   This affects the number of iterations used in the hashing process.
+ *   A larger value is more secure, but takes more time to complete.
+ */
+function _passwordhash_gensalt_private($iteration_count_log2 = 0) {
+  $itoa64 = _passwordhash_itoa64();
+  // Minimum log2 iterations is DRUPAL_HASH_ITERATION.
+  $iteration_count_log2 = max($iteration_count_log2, DRUPAL_HASH_ITERATION);
+  $output = '$P$';
+  // Maximum log2 iterations is 30.
+  $output .= $itoa64[min($iteration_count_log2, 30)];
+  $output .= _passwordhash_encode64(_passwordhash_random_bytes(6), 6);
+
+  return $output;
+}
+
+/**
+ * Hash a password using a secure portable hash.
+ *
+ * @param $password
+ *   The password to hash
+ * @param $setting
+ *   An existing hash or the output of _passwordhash_gensalt_private()
+ *
+ * @return
+ *   The hashed password or FALSE on failure.
+ */
+function _passwordhash_crypt_private($password, $setting)  {
+
+  if (substr($setting, 0, 3) != '$P$') {
+    return FALSE;
+  }
+
+  $count_log2 = _passwordhash_get_count_log2($setting);
+  // Portable hashes may come from elsewhere, so we allow < DRUPAL_HASH_ITERATION
+  if ($count_log2 < 7 || $count_log2 > 30) {
+    return FALSE;
+  }
+
+  $salt = substr($setting, 4, 8);
+  if (strlen($salt) != 8) {
+    return FALSE;
+  }
+
+  // We're kind of forced to use MD5 here since it's the only
+  // cryptographic primitive available in all versions of PHP
+  // currently in use.  To implement our own low-level crypto
+  // in PHP would result in much worse performance and
+  // consequently in lower iteration counts and hashes that are
+  // quicker to crack (by non-PHP code).
+
+  $count = 1 << $count_log2;
+
+  $hash = md5($salt . $password, TRUE);
+  do {
+    $hash = md5($hash . $password, TRUE);
+  } while (--$count);
+
+  $output = substr($setting, 0, 12);
+  $output .= _passwordhash_encode64($hash, 16);
+
+  return (strlen($output) == 34) ? $output : FALSE;
+}
+
+function _passwordhash_get_count_log2($stored_hash) {
+  $itoa64 = _passwordhash_itoa64();
+  return strpos($itoa64, $stored_hash[3]);
+}
+
+/**
+ * Hash a password using a secure hash.
+ *
+ * @param $password
+ *   A plain-text password
+ *
+ * @return
+ *   A string containing the hashed password (and a salt), or FALSE on failure.
+ */
+function user_hash_password($password) {
+  return _passwordhash_crypt_private($password, _passwordhash_gensalt_private());
+}
+
+/**
+ * Check whether a plain text password matches a stored hashed password.
+ *
+ * @param $password
+ *   A plain-text password
+ * @param $account
+ *   A user object with at least the fields from the {users} table.
+ *
+ * @return
+ *   TRUE or FALSE.
+ */
+function user_check_password($password, $account) {
+  if (strlen($account->pass) <= 32 || (substr($account->pass, 0, 3) != '$P$')) {
+    // This may be an updated password that was re-hashed with MD5 in
+    // system_update_7001().
+    return $account->pass == md5($account->init . $account->created . md5($password));
+  }
+  else {
+    $hash = _passwordhash_crypt_private($password, $account->pass);
+    return ($hash && $account->pass == $hash);
+  }
+}
+
+/**
+ * Check whether a user's hashed password needs to be replaced with a new hash.
+ *
+ * @param $account
+ *   A user object with at least the fields from the {users} table.
+ *
+ * @return
+ *   TRUE or FALSE.
+ */
+function user_needs_rehash($account) {
+  // Check whether this was an updated password - i.e. still a normal MD5.
+  if (strlen($account->pass) <= 32 || (substr($account->pass, 0, 3) != '$P$')) {
+    return TRUE;
+  }
+  // Check whether the iteration count used is less than the standard number.
+  return (_passwordhash_get_count_log2($account->pass) < DRUPAL_HASH_ITERATION);
+}
+
Index: modules/system/system.install
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system.install,v
retrieving revision 1.239
diff -u -p -r1.239 system.install
--- modules/system/system.install	20 Feb 2008 13:46:41 -0000	1.239
+++ modules/system/system.install	23 Feb 2008 00:33:04 -0000
@@ -2505,6 +2505,20 @@ function system_update_7000() {
 }
 
 /**
+ * Increase the length of the password field to accomodate better hashes.
+ *
+ * Also re-hashes all current passwords with CONCAT(init, created) as a salt. 
+ * This provides a very modest immediate improvement in security.
+ */
+function system_update_7001() {
+  $ret = array();
+  db_change_field($ret, 'users', 'pass', 'pass', array('type' => 'varchar', 'length' => 128, 'not null' => TRUE, 'default' => ''));
+  // Rehash with a salt all current hashed passwords.
+  $ret[] = update_sql("UPDATE {users} SET pass = MD5(CONCAT(CONCAT(init, created), pass)) WHERE uid > 0");
+  return $ret;
+}
+
+/**
  * @} End of "defgroup updates-6.x-to-7.x"
  * The next series of updates should start at 8000.
  */
Index: modules/user/user.install
===================================================================
RCS file: /cvs/drupal/drupal/modules/user/user.install,v
retrieving revision 1.6
diff -u -p -r1.6 user.install
--- modules/user/user.install	18 Feb 2008 16:53:36 -0000	1.6
+++ modules/user/user.install	23 Feb 2008 00:33:05 -0000
@@ -144,10 +144,10 @@ function user_schema() {
       ),
       'pass' => array(
         'type' => 'varchar',
-        'length' => 32,
+        'length' => 128,
         'not null' => TRUE,
         'default' => '',
-        'description' => t("User's password (md5 hash)."),
+        'description' => t("User's password (hashed)."),
       ),
       'mail' => array(
         'type' => 'varchar',
Index: modules/user/user.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/user/user.module,v
retrieving revision 1.896
diff -u -p -r1.896 user.module
--- modules/user/user.module	20 Feb 2008 13:46:43 -0000	1.896
+++ modules/user/user.module	23 Feb 2008 00:33:05 -0000
@@ -157,7 +157,7 @@ function user_load($array = array()) {
     }
     else if ($key == 'pass') {
       $query[] = "pass = '%s'";
-      $params[] = md5($value);
+      $params[] = $value;
     }
     else {
       $query[]= "LOWER($key) = LOWER('%s')";
@@ -214,7 +214,9 @@ function user_save($account, $array = ar
   $user_fields = $table['fields'];
 
   if (!empty($array['pass'])) {
-    $array['pass'] = md5($array['pass']);
+    // Allow alternate hashing schemes.
+    require_once variable_get('passwordhash.inc', './includes/passwordhash.inc');
+    $array['pass'] = user_hash_password(trim($array['pass']));
   }
   else {
     // Avoid overwriting an existing password with a blank password.
@@ -1283,12 +1285,26 @@ function user_login_final_validate($form
 function user_authenticate($form_values = array()) {
   global $user;
 
+  $password = trim($form_values['pass']);
   // Name and pass keys are required.
-  if (!empty($form_values['name']) && !empty($form_values['pass']) &&
-      $account = user_load(array('name' => $form_values['name'], 'pass' => trim($form_values['pass']), 'status' => 1))) {
-    $user = $account;
-    user_authenticate_finalize($form_values);
-    return $user;
+  if (!empty($form_values['name']) && !empty($password)) {
+    $account = db_fetch_object(db_query("SELECT * FROM {users} WHERE name = '%s' AND status = 1", $form_values['name']));
+    if ($account) {
+      // Allow alternate hashing schemes.
+      require_once variable_get('passwordhash.inc', './includes/passwordhash.inc');
+      if (user_check_password($password, $account)) {
+        if (user_needs_rehash($account)) {
+           $new_hash = user_hash_password($password);
+           if ($new_hash) {
+             db_query("UPDATE {users} SET pass = '%s' WHERE uid = %d", $new_hash, $account->uid);
+           }
+        }
+        $account = user_load(array('uid' => $account->uid, 'status' => 1));
+        $user = $account;
+        user_authenticate_finalize($form_values);
+        return $user;
+      }
+    }
   }
 }