RC4 CryptoAPI to PHP port

[kguller]

Hello, I am trying to emulate a working CryptoAPI RC4 encrypt/decrypt routine in PHP. When doing so, I've run into a problem trying to recreate the CryptCreateHash +CryptHashData process. I'm trying to figure out how CryptoAPI orders/combines the raw data when calling CryptHashData multiple times.

For example:

// I create the hash variable, then hash a binary string using CryptHashData and then hash a secret using CryptHashData again.

BYTE baKeyRandom[10] = {87,253, ...};
::CryptCreateHash(hCryptProv, CALG_MD5, 0, 0, &hSaveHash);
::CryptHashData(hSaveHash, baKeyRandom, (DWORD)sizeof(baKeyRandom), 0);
::CryptHashData(hSaveHash, (LPBYTE)T2CW(pszSecret), (DWORD)_tcslen(pszSecret) * sizeof(WCHAR), 0);

Then in PHP I'm trying to do something similar

// server key secret
$secret = 'ABCDEF-G...';

// random byte string
$random = pack('c*', 87,253, ...);

// simple concat does not work to generate an MD5 key
$key = md5($random.$secret);

So the question is how to emulate this step and match the C++ CryptoApi MD5 hash key in php

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