Bug #63208 [Opn->Ana]: Wrong conversion of byte array VARIANT which contains null byte to string

From: Date: Sun, 16 Aug 2015 16:25:45 +0000
Subject: Bug #63208 [Opn->Ana]: Wrong conversion of byte array VARIANT which contains null byte to string
References: 1  Groups: php.bugs 
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Edit report at https://bugs.php.net/bug.php?id=63208&edit=1 ID: 63208 Updated by: cmb@php.net Reported by: gopeyx at gmail dot com Summary: Wrong conversion of byte array VARIANT which contains null byte to string -Status: Open +Status: Analyzed Type: Bug Package: COM related Operating System: Windows NT W-AM-13079 6.1 build PHP Version: 5.3.17 Block user comment: N Private report: N New Comment: The problem is that php_com_olestring_to_string()[1] is not binary safe, because it passes -1 to the cchWideChar parameter of WideCharToMultiByte()[2]. That causes WideCharToMultiByte() to stop at the first null character (actually, two null bytes), and so the rest of the string is ignored. As a BSTR[3] has a prefix containing its length in bytes it appears we could use this to calculate the proper cchWideChar argument, see the attached patch. [1] <https://github.com/php/php-src/blob/php-7.0.0beta3/ext/com_dotnet/com_olechar.c#L74> [2] <https://msdn.microsoft.com/en-us/library/windows/desktop/dd374130(v=vs.85).aspx> [3] <https://msdn.microsoft.com/en-us/library/windows/desktop/ms221069(v=vs.85).aspx> Previous Comments: ------------------------------------------------------------------------ [2012-10-11 15:38:01] tomas dot var at dtr-sistemas dot com I have the same problem when I want to extract the value of a LONGBINARY field from an MS-Access or MSSQL Database (OLE Field exactly), and the OLE embeeded header contains some zero bytes. I can obtain only 3 bytes when it converts to a string for save to a file. And when I loop with "foreach" the VARIANT ARRAY of UNSIGNED BYTES it loops correctly (except for the byte '\0' after every valid byte) and if I count the array with "count($field->Value)" for example, it results the double lenght that expects. Why don't exists in PHP a way to obtain a simple array of bytes for a variable, or access the data like a "string" of bytes? ------------------------------------------------------------------------ [2012-10-03 12:40:18] gopeyx at gmail dot com Description: ------------ I have a VARIANT of type 8209 which is an array of bytes (VT_ARRAY | VT_UI1). This array contains null byte in the middle. When trying to convert it to a string only bytes before null byte are used. Others are ignored. But they are present in the object. You can see it if you walk through the bytes of variant via foreach(). Test script: --------------- <?php $string = "ab\0cd"; $variant = new VARIANT($string, VT_ARRAY | VT_UI1); // Array of bytes $converted = (string) $variant; var_dump($string); var_dump($converted); Expected result: ---------------- string(5) "abcd" string(5) "abcd" // $converted variable should be equal to the original $string and should contain 5 characters. Actual result: -------------- string(5) "abcd" string(2) "ab" ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=63208&edit=1

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