Merge "Lower CDN cache TTL when slave lag is high"

[lhc/web/wiklou.git] / includes / utils / MWCryptRand.php

diff --git a/includes/utils/MWCryptRand.php b/includes/utils/MWCryptRand.php
index f223790..53c77c2 100644 (file)
--- a/includes/utils/MWCryptRand.php
+++ b/includes/utils/MWCryptRand.php
@@ -43,16 +43,6 @@ class MWCryptRand {
         */
        protected static $singleton = null;
 
-       /**
-        * The hash algorithm being used
-        */
-       protected $algo = null;
-
-       /**
-        * The number of bytes outputted by the hash algorithm
-        */
-       protected $hashLength = null;
-
        /**
         * A boolean indicating whether the previous random generation was done using
         * cryptographically strong random number generator or not.
@@ -156,7 +146,7 @@ class MWCryptRand {
                // loop to gather little entropy)
                $minIterations = self::MIN_ITERATIONS;
                // Duration of time to spend doing calculations (in seconds)
-               $duration = ( self::MSEC_PER_BYTE / 1000 ) * $this->hashLength();
+               $duration = ( self::MSEC_PER_BYTE / 1000 ) * MWCryptHash::hashLength();
                // Create a buffer to use to trigger memory operations
                $bufLength = 10000000;
                $buffer = str_repeat( ' ', $bufLength );
@@ -183,7 +173,7 @@ class MWCryptRand {
                        $iterations++;
                }
                $timeTaken = $currentTime - $startTime;
-               $data = $this->hash( $data );
+               $data = MWCryptHash::hash( $data );
 
                wfDebug( __METHOD__ . ": Clock drift calculation " .
                        "(time-taken=" . ( $timeTaken * 1000 ) . "ms, " .
@@ -203,7 +193,7 @@ class MWCryptRand {
                        // Initialize the state with whatever unstable data we can find
                        // It's important that this data is hashed right afterwards to prevent
                        // it from being leaked into the output stream
-                       $state = $this->hash( $this->initialRandomState() );
+                       $state = MWCryptHash::hash( $this->initialRandomState() );
                }
                // Generate a new random state based on the initial random state or previous
                // random state by combining it with clock drift
@@ -212,73 +202,6 @@ class MWCryptRand {
                return $state;
        }
 
-       /**
-        * Decide on the best acceptable hash algorithm we have available for hash()
-        * @throws MWException
-        * @return string A hash algorithm
-        */
-       protected function hashAlgo() {
-               if ( !is_null( $this->algo ) ) {
-                       return $this->algo;
-               }
-
-               $algos = hash_algos();
-               $preference = array( 'whirlpool', 'sha256', 'sha1', 'md5' );
-
-               foreach ( $preference as $algorithm ) {
-                       if ( in_array( $algorithm, $algos ) ) {
-                               $this->algo = $algorithm;
-                               wfDebug( __METHOD__ . ": Using the {$this->algo} hash algorithm.\n" );
-
-                               return $this->algo;
-                       }
-               }
-
-               // We only reach here if no acceptable hash is found in the list, this should
-               // be a technical impossibility since most of php's hash list is fixed and
-               // some of the ones we list are available as their own native functions
-               // But since we already require at least 5.2 and hash() was default in
-               // 5.1.2 we don't bother falling back to methods like sha1 and md5.
-               throw new MWException( "Could not find an acceptable hashing function in hash_algos()" );
-       }
-
-       /**
-        * Return the byte-length output of the hash algorithm we are
-        * using in self::hash and self::hmac.
-        *
-        * @return int Number of bytes the hash outputs
-        */
-       protected function hashLength() {
-               if ( is_null( $this->hashLength ) ) {
-                       $this->hashLength = strlen( $this->hash( '' ) );
-               }
-
-               return $this->hashLength;
-       }
-
-       /**
-        * Generate an acceptably unstable one-way-hash of some text
-        * making use of the best hash algorithm that we have available.
-        *
-        * @param string $data
-        * @return string A raw hash of the data
-        */
-       protected function hash( $data ) {
-               return hash( $this->hashAlgo(), $data, true );
-       }
-
-       /**
-        * Generate an acceptably unstable one-way-hmac of some text
-        * making use of the best hash algorithm that we have available.
-        *
-        * @param string $data
-        * @param string $key
-        * @return string A raw hash of the data
-        */
-       protected function hmac( $data, $key ) {
-               return hash_hmac( $this->hashAlgo(), $data, $key, true );
-       }
-
        /**
         * @see self::wasStrong()
         */
@@ -407,7 +330,7 @@ class MWCryptRand {
                                ": Falling back to using a pseudo random state to generate randomness.\n" );
                }
                while ( strlen( $buffer ) < $bytes ) {
-                       $buffer .= $this->hmac( $this->randomState(), mt_rand() );
+                       $buffer .= MWCryptHash::hmac( $this->randomState(), mt_rand() );
                        // This code is never really cryptographically strong, if we use it
                        // at all, then set strong to false.
                        $this->strong = false;