From d293a19804fb4c1c06a0797489c62b34b428bae9 Mon Sep 17 00:00:00 2001
From: Daniel Friesen <dantman@users.mediawiki.org>
Date: Mon, 20 Feb 2012 22:35:14 +0000
Subject: [PATCH] Revert CryptRand class in r111964 till after the git
 migration.

---
 includes/AutoLoader.php |   1 -
 includes/CryptRand.php  | 252 ----------------------------------------
 2 files changed, 253 deletions(-)
 delete mode 100644 includes/CryptRand.php

diff --git a/includes/AutoLoader.php b/includes/AutoLoader.php
index 74165806a6..4540c7958f 100644
--- a/includes/AutoLoader.php
+++ b/includes/AutoLoader.php
@@ -49,7 +49,6 @@ $wgAutoloadLocalClasses = array(
 	'ConfEditorToken' => 'includes/ConfEditor.php',
 	'Cookie' => 'includes/Cookie.php',
 	'CookieJar' => 'includes/Cookie.php',
-	'MWCryptRand' => 'includes/CryptRand.php',
 	'CurlHttpRequest' => 'includes/HttpFunctions.php',
 //	'DBDataObject' => 'includes/DBDataObject.php',
 //	'DBTable' => 'includes/DBTable.php',
diff --git a/includes/CryptRand.php b/includes/CryptRand.php
deleted file mode 100644
index 86332129df..0000000000
--- a/includes/CryptRand.php
+++ /dev/null
@@ -1,252 +0,0 @@
-<?php
-/**
- * A static cryptographic random generator class used for generating secret keys
- *
- * This is based in part on Drupal code as well as what we used in our own code
- * prior to introduction of this class.
- *
- * @file
- */
-
-final class MWCryptRand {
-
-	/**
-	 * Initialize an initial random state based off of whatever we can find
-	 */
-	private static function initialRandomState() {
-		// $_SERVER contains a variety of unstable user and system specific information
-		// It'll vary a little with each page, and vary even more with separate users
-		// It'll also vary slightly across different machines
-		$state = serialize( $_SERVER );
-
-		// To try and vary the system information of the state a bit more
-		// by including the system's hostname into the state
-		$state .= wfHostname();
-
-		// Try and make this a little more unstable by including the varying process
-		// id of the php process we are running inside of if we are able to access it
-		if ( function_exists( 'getmypid' ) ) {
-			$state .= getmypid();
-		}
-
-		// If available try to increase the instability of the data by throwing in
-		// the precise amount of memory that we happen to be using at the moment.
-		if ( function_exists( 'memory_get_usage' ) ) {
-			$state .= memory_get_usage( true );
-		}
-
-		// It's mostly worthless but throw the wiki's id into the data for a little more variance
-		$state .= wfWikiID();
-
-		// If we have a secret key or proxy key set then throw it into the state as well
-		global $wgSecretKey, $wgProxyKey;
-		if ( $wgSecretKey ) {
-			$state .= $wgSecretKey;
-		} elseif ( $wgProxyKey ) {
-			$state .= $wgProxyKey;
-		}
-
-		return $state;
-	}
-
-	/**
-	 * Return a rolling random state initially build using data from unstable sources
-	 * @return A new weak random state
-	 */
-	public static function randomState() {
-		static $state = null;
-		if ( is_null( $state ) ) {
-			// 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 = self::initialRandomState();
-		}
-		// Generate a new random state based on the initial random state or previous
-		// random state by combining it with both the current time and a random value
-		// Simple append/prepend based methods of combining data and a salt have
-		// weaknesses in them, take advantage of the availability of hmac to abuse
-		// it's method of combining data and a key into a hash which is free of
-		// the typical weakness of simple concatenation
-		// Note that in hmac large keys are reduced in size and the key is then
-		// xor-ed to create two separate keys. For this reason we use the smaller
-		// time+rand as the key and the larger state as the data.
-		// We also don't bother passing numbers to mt_rand since you can't make
-		// it generate with any more entropy than it's default max value.
-		$state = self::hmac( $state, microtime() . mt_rand() );
-		return $state;
-	}
-
-	/**
-	 * Decide on the best acceptable hash algorithm we have available for hash()
-	 * @return String A hash algorithm
-	 */
-	private static function hashAlgo() {
-		static $algo = null;
-		if ( !is_null( $algo ) ) {
-			return $algo;
-		}
-
-		$algos = hash_algos();
-		$preference = array( 'whirlpool', 'sha256', 'sha1', 'md5' );
-
-		foreach ( $preference as $algorithm ) {
-			if ( in_array( $algorithm, $algos ) ) {
-				$algo = $algorithm; # assign to static
-				return $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()" );
-	}
-
-	/**
-	 * Generate an acceptably unstable one-way-hash of some text
-	 * making use of the best hash algorithm that we have available.
-	 *
-	 * @return String A raw hash of the data
-	 */
-	private static function hash( $data ) {
-		return hash( self::hashAlgo(), $data, true );
-	}
-
-	/**
-	 * Generate an acceptably unstable one-way-hmac of some text
-	 * making use of the best hash algorithm that we have available.
-	 *
-	 * @return String A raw hash of the data
-	 */
-	private static function hmac( $data, $key ) {
-		return hash_hmac( self::hashAlgo(), $data, $key, true );
-	}
-
-
-
-	private static $strong = null;
-
-	/**
-	 * Return a boolean indicating whether or not the source used for cryptographic
-	 * random bytes generation in the previously run generate* call
-	 * was cryptographically strong.
-	 *
-	 * @return bool Returns true if the source was strong, false if not.
-	 */
-	public static function wasStrong() {
-		if ( is_null( self::$strong ) ) {
-			throw new MWException( __METHOD__ . ' called before generation of random data' );
-		}
-		return self::$strong;
-	}
-
-	/**
-	 * Generate a run of (ideally) cryptographically random data and return
-	 * it in raw binary form.
-	 * You can use MWCryptRand::wasStrong() if you wish to know if the source used
-	 * was cryptographically strong.
-	 *
-	 * @param $bytes int the number of bytes of random data to generate
-	 * @return String Raw binary random data
-	 */
-	public static function generate( $bytes ) {
-		$bytes = floor( $bytes );
-		static $buffer = '';
-		if ( is_null( self::$strong ) ) {
-			// Set strength to false initially until we know what source data is coming from
-			self::$strong = true;
-		}
-
-		if ( strlen( $buffer ) < $bytes ) {
-			// /dev/urandom is generally considered the best possible commonly
-			// available random source, and is available on most *nix systems.
-			wfSuppressWarnings();
-			$urandom = fopen( "/dev/urandom", "rb" );
-			wfRestoreWarnings();
-
-			// Attempt to read all our random data from urandom
-			// php's fread always does buffered reads based on the stream's chunk_size
-			// so in reality it will usually read more than the amount of data we're
-			// asked for and it doesn't cost anything extra to store that.
-			// We don't have access to the stream's chunk_size, fread maxes out at 8k
-			// so we'll go along with Drupal's decision to read at least 4k
-			if ( $urandom ) {
-				$buffer .= fread( $urandom, max( 1024 * 4, $bytes ) );
-				fclose( $urandom );
-				if ( strlen( $buffer ) >= $bytes ) {
-					// urandom is always strong, set to true if all our data was generated using it
-					self::$strong = true;
-				}
-			}
-		}
-
-		if ( strlen( $buffer ) < $bytes ) {
-			// If available and we failed to read enough data out of urandom make use
-			// of openssl's random_pesudo_bytes method to attempt to generate randomness.
-			// However don't do this on Windows with PHP < 5.3.4 due to a bug:
-			// http://stackoverflow.com/questions/1940168/openssl-random-pseudo-bytes-is-slow-php
-			if ( ( $bytes - strlen( $buffer ) > 0 )
-				&& function_exists( 'openssl_random_pseudo_bytes' )
-				&& ( !wfIsWindows() || version_compare( PHP_VERSION, '5.3.4', '>=' ) )
-			) {
-				$buffer .= openssl_random_pseudo_bytes( $bytes - strlen( $buffer ), $openssl_strong );
-				if ( strlen( $buffer ) >= $bytes ) {
-					// openssl tells us if the random source was strong, if some of our data was generated
-					// using it use it's say on whether the randomness is strong
-					self::$strong = !!$openssl_strong;
-				}
-			}
-		}
-
-
-		// If we cannot use or generate enough data from /dev/urandom or openssl
-		// use this loop to generate a good set of pesudo random data.
-		// This works by initializing a random state using a pile of unstable data
-		// and continually shoving it through a hash along with a variable salt.
-		// We hash the random state with more salt to avoid the state from leaking
-		// out and being used to predict the /randomness/ that follows.
-		while ( strlen( $buffer ) < $bytes ) {
-			$buffer .= self::hmac( self::randomState(), mt_rand() );
-			// This code is never really cryptographically strong, if we use it
-			// at all, then set strong to false.
-			self::$strong = false;
-		}
-
-		// Once the buffer has been filled up with enough random data to fulfill
-		// the request shift off enough data to handle the request and leave the
-		// unused portion left inside the buffer for the next request for random data
-		$generated = substr( $buffer, 0, $bytes );
-		$buffer = substr( $buffer, $bytes );
-
-		return $generated;
-	}
-
-	/**
-	 * Generate a run of (ideally) cryptographically random data and return
-	 * it in hexadecimal string format.
-	 * You can use MWCryptRand::wasStrong() if you wish to know if the source used
-	 * was cryptographically strong.
-	 *
-	 * @param $chars int the number of hex chars of random data to generate
-	 * @return String Hexadecimal random data
-	 */
-	public static function generateHex( $chars ) {
-		// hex strings are 2x the length of raw binary so we divide the length in half
-		// odd numbers will result in a .5 that leads the generate() being 1 character
-		// short, so we use ceil() to ensure that we always have enough bytes
-		$bytes = ceil( $chars / 2 );
-		// Generate the data and then convert it to a hex string
-		$hex = bin2hex( self::generate( $bytes ) );
-		// A bit of paranoia here, the caller asked for a specific length of string
-		// here, and it's possible (eg when given an odd number) that we may actually
-		// have at least 1 char more than they asked for. Just in case they made this
-		// call intending to insert it into a database that does truncation we don't
-		// want to give them too much and end up with their database and their live
-		// code having two different values because part of what we gave them is truncated
-		// hence, we strip out any run of characters longer than what we were asked for.
-		return substr( $hex, 0, $chars );
-	}
-
-}
-- 
2.20.1