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    1: /*
    2:    +----------------------------------------------------------------------+
    3:    | Suhosin-Patch for PHP                                                |
    4:    +----------------------------------------------------------------------+
    5:    | Copyright (c) 2004-2009 Stefan Esser                                 |
    6:    +----------------------------------------------------------------------+
    7:    | This source file is subject to version 2.02 of the PHP license,      |
    8:    | that is bundled with this package in the file LICENSE, and is        |
    9:    | available at through the world-wide-web at                           |
   10:    | http://www.php.net/license/2_02.txt.                                 |
   11:    | If you did not receive a copy of the PHP license and are unable to   |
   12:    | obtain it through the world-wide-web, please send a note to          |
   13:    | license@php.net so we can mail you a copy immediately.               |
   14:    +----------------------------------------------------------------------+
   15:    | Author: Stefan Esser <stefan.esser@sektioneins.de>                   |
   16:    +----------------------------------------------------------------------+
   17:  */
   18: /* $Id: zend_canary.c,v 1.1.1.1 2012/02/21 23:47:52 misho Exp $ */
   19: 
   20: #include "zend.h"
   21: 
   22: #include <stdio.h>
   23: #include <stdlib.h>
   24: 
   25: 
   26: #if SUHOSIN_PATCH
   27: 
   28: static size_t last_canary = 0x73625123;
   29: 
   30: /* will be replaced later with more compatible method */
   31: ZEND_API void zend_canary(void *buf, int len)
   32: {
   33: 	time_t t;
   34: 	size_t canary;
   35: 	int fd;
   36: 	
   37: #ifndef PHP_WIN32
   38: 	fd = open("/dev/urandom", 0);
   39: 	if (fd != -1) {
   40: 		int r = read(fd, buf, len);
   41: 		close(fd);
   42: 		if (r == len) {
   43: 			return;
   44: 		}
   45: 	}
   46: #endif	
   47: 	/* not good but we never want to do this */
   48: 	time(&t);
   49: 	canary = *(unsigned int *)&t + getpid() << 16 + last_canary;
   50: 	last_canary ^= (canary << 5) | (canary >> (32-5));
   51: 	/* When we ensure full win32 compatibility in next version
   52: 	   we will replace this with the random number code from zend_alloc.c */
   53:         memcpy(buf, &canary, len);
   54: }
   55: 
   56: #endif
   57: 
   58: 
   59: /*
   60:  * Local variables:
   61:  * tab-width: 4
   62:  * c-basic-offset: 4
   63:  * End:
   64:  * vim600: sw=4 ts=4 fdm=marker
   65:  * vim<600: sw=4 ts=4
   66:  */