1 files changed, 109 insertions, 0 deletions
diff --git a/extlib/Auth/OpenID/Nonce.php b/extlib/Auth/OpenID/Nonce.php
new file mode 100644
index 000000000..effecac38
--- /dev/null
+++ b/extlib/Auth/OpenID/Nonce.php
@@ -0,0 +1,109 @@
+<?php
+
+/**
+ * Nonce-related functionality.
+ *
+ * @package OpenID
+ */
+
+/**
+ * Need CryptUtil to generate random strings.
+ */
+require_once 'Auth/OpenID/CryptUtil.php';
+
+/**
+ * This is the characters that the nonces are made from.
+ */
+define('Auth_OpenID_Nonce_CHRS',"abcdefghijklmnopqrstuvwxyz" .
+       "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789");
+
+// Keep nonces for five hours (allow five hours for the combination of
+// request time and clock skew). This is probably way more than is
+// necessary, but there is not much overhead in storing nonces.
+global $Auth_OpenID_SKEW;
+$Auth_OpenID_SKEW = 60 * 60 * 5;
+
+define('Auth_OpenID_Nonce_REGEX',
+       '/(\d{4})-(\d\d)-(\d\d)T(\d\d):(\d\d):(\d\d)Z(.*)/');
+
+define('Auth_OpenID_Nonce_TIME_FMT',
+       '%Y-%m-%dT%H:%M:%SZ');
+
+function Auth_OpenID_splitNonce($nonce_string)
+{
+    // Extract a timestamp from the given nonce string
+    $result = preg_match(Auth_OpenID_Nonce_REGEX, $nonce_string, $matches);
+    if ($result != 1 || count($matches) != 8) {
+        return null;
+    }
+
+    list($unused,
+         $tm_year,
+         $tm_mon,
+         $tm_mday,
+         $tm_hour,
+         $tm_min,
+         $tm_sec,
+         $uniquifier) = $matches;
+
+    $timestamp =
+        @gmmktime($tm_hour, $tm_min, $tm_sec, $tm_mon, $tm_mday, $tm_year);
+
+    if ($timestamp === false || $timestamp < 0) {
+        return null;
+    }
+
+    return array($timestamp, $uniquifier);
+}
+
+function Auth_OpenID_checkTimestamp($nonce_string,
+                                    $allowed_skew = null,
+                                    $now = null)
+{
+    // Is the timestamp that is part of the specified nonce string
+    // within the allowed clock-skew of the current time?
+    global $Auth_OpenID_SKEW;
+
+    if ($allowed_skew === null) {
+        $allowed_skew = $Auth_OpenID_SKEW;
+    }
+
+    $parts = Auth_OpenID_splitNonce($nonce_string);
+    if ($parts == null) {
+        return false;
+    }
+
+    if ($now === null) {
+        $now = time();
+    }
+
+    $stamp = $parts[0];
+
+    // Time after which we should not use the nonce
+    $past = $now - $allowed_skew;
+
+    // Time that is too far in the future for us to allow
+    $future = $now + $allowed_skew;
+
+    // the stamp is not too far in the future and is not too far
+    // in the past
+    return (($past <= $stamp) && ($stamp <= $future));
+}
+
+function Auth_OpenID_mkNonce($when = null)
+{
+    // Generate a nonce with the current timestamp
+    $salt = Auth_OpenID_CryptUtil::randomString(
+        6, Auth_OpenID_Nonce_CHRS);
+    if ($when === null) {
+        // It's safe to call time() with no arguments; it returns a
+        // GMT unix timestamp on PHP 4 and PHP 5.  gmmktime() with no
+        // args returns a local unix timestamp on PHP 4, so don't use
+        // that.
+        $when = time();
+    }
+    $time_str = gmstrftime(Auth_OpenID_Nonce_TIME_FMT, $when);
+    return $time_str . $salt;
+}
+
+?>
+\ No newline at end of file