CWE-ou-minkata/Sources/Plasma/NucleusLib/pnUtils/Private/pnUtCrypt.cpp

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*==LICENSE==*/
/*****************************************************************************
*
*   $/Plasma20/Sources/Plasma/NucleusLib/pnUtils/Private/pnUtCrypt.cpp
*   
***/

#include "../Pch.h"
#pragma hdrstop

#include <openssl/md5.h>
#include <openssl/sha.h>
#include <openssl/rc4.h>

/*****************************************************************************
*
*   Opaque types
*
***/

struct CryptKey {
    ECryptAlgorithm algorithm;
    void *          handle;
};


/*****************************************************************************
*
*   Private
*
***/

namespace Crypt {

ShaDigest s_shaSeed;


/*****************************************************************************
*
*   Internal functions
*
***/

//============================================================================
void Md5Process (
    void *          dest,
    unsigned        sourceCount,
    const unsigned  sourceBytes[],
    const void *    sourcePtrs[]
) {
    // initialize digest
    MD5_CTX md5;
    MD5_Init(&md5);

    // hash data streams
    for (unsigned index = 0; index < sourceCount; ++index)
        MD5_Update(&md5, sourcePtrs[index], sourceBytes[index]);

    // complete hashing
    MD5_Final((unsigned char *)dest, &md5);
}

//============================================================================
void ShaProcess (
    void *          dest,
    unsigned        sourceCount,
    const unsigned  sourceBytes[],
    const void *    sourcePtrs[]
) {
    // initialize digest
    SHA_CTX sha;
    SHA_Init(&sha);

    // hash data streams
    for (unsigned index = 0; index < sourceCount; ++index)
        SHA_Update(&sha, sourcePtrs[index], sourceBytes[index]);

    // complete hashing
    SHA_Final((unsigned char *)dest, &sha);
}

//============================================================================
void Sha1Process (
    void *          dest,
    unsigned        sourceCount,
    const unsigned  sourceBytes[],
    const void *    sourcePtrs[]
) {
    // initialize digest
    SHA_CTX sha;
    SHA1_Init(&sha);

    // hash data streams
    for (unsigned index = 0; index < sourceCount; ++index)
        SHA1_Update(&sha, sourcePtrs[index], sourceBytes[index]);

    // complete hashing
    SHA1_Final((unsigned char *)dest, &sha);
}


/*****************************************************************************
*
*   RC4
*
***/

//============================================================================
static void Rc4Codec (
    CryptKey *      key,
    bool            encrypt,
    ARRAY(byte) *   dest,
    unsigned        sourceBytes,
    const void *    sourceData
) {
    // RC4 uses the same algorithm to both encrypt and decrypt
    dest->SetCount(sourceBytes);
    RC4((RC4_KEY *)key->handle, sourceBytes, (const unsigned char *)sourceData, dest->Ptr());
}

//============================================================================
static void Rc4Codec (
    CryptKey *      key,
    bool            encrypt,
    unsigned        bytes,
    void *          data
) {
    // RC4 uses the same algorithm to both encrypt and decrypt
    byte * temp = ALLOCA(byte, bytes);
    RC4((RC4_KEY *)key->handle, bytes, (const unsigned char *)data, temp);
    MemCopy(data, temp, bytes);
}

} using namespace Crypt;


/*****************************************************************************
*
*   Exports
*
***/

//============================================================================
void CryptDigest (
    ECryptAlgorithm algorithm,
    void *          dest,           // must be sized to the algorithm's digest size
    const unsigned  sourceBytes,
    const void *    sourceData
) {
    CryptDigest(
        algorithm,
        dest,
        1,
        &sourceBytes,
        &sourceData
    );
}

//============================================================================
void CryptDigest (
    ECryptAlgorithm algorithm,
    void *          dest,           // must be sized to the algorithm's digest size
    unsigned        sourceCount,
    const unsigned  sourceBytes[],  // [sourceCount]
    const void *    sourcePtrs[]    // [sourceCount]
) {
    switch (algorithm) {
        case kCryptMd5:
            Md5Process(dest, sourceCount, sourceBytes, sourcePtrs);
        break;

        case kCryptSha:
            ShaProcess(dest, sourceCount, sourceBytes, sourcePtrs);
        break;

        case kCryptSha1:
            Sha1Process(dest, sourceCount, sourceBytes, sourcePtrs);
        break;

        DEFAULT_FATAL(algorithm);
    }
}

//============================================================================
CryptKey * CryptKeyCreate (
    ECryptAlgorithm algorithm,
    unsigned        bytes,
    const void *    data
) {
    CryptKey * key = nil;
    switch (algorithm) {
        case kCryptRc4: {
            RC4_KEY * rc4 = NEW(RC4_KEY);
            RC4_set_key(rc4, bytes, (const unsigned char *)data);
            key = NEW(CryptKey);
            key->algorithm = kCryptRc4;
            key->handle = rc4;
        }
        break;

        case kCryptRsa: // Not implemented; fall-thru to FATAL
//      break;

        DEFAULT_FATAL(algorithm);
    }

    return key;
}

//============================================================================
void CryptKeyClose (
    CryptKey *      key
) {
    if (!key)
        return;

    DEL(key->handle);
    DEL(key);
}

//============================================================================
unsigned CryptKeyGetBlockSize (
    CryptKey *      key
) {
    switch (key->algorithm) {
        case kCryptRc4: {
            return 1;
        }
        break;

        case kCryptRsa: // Not implemented; fall-thru to FATAL
//            return RsaGetBlockSize(key);

        DEFAULT_FATAL(algorithm);
    }
}

//============================================================================
void CryptCreateRandomSeed (
    unsigned        bytes,
    byte *          data
) {
    COMPILER_ASSERT(SHA_DIGEST_LENGTH == 20);

    // Combine seed with input data
    {
        unsigned seedIndex = 0;
        unsigned dataIndex = 0;
        unsigned cur = 0;
        unsigned end = max(bytes, sizeof(s_shaSeed));
        for (; cur < end; ++cur) {
            ((byte *) &s_shaSeed)[seedIndex] ^= data[dataIndex];
            if (++seedIndex >= sizeof(s_shaSeed))
                seedIndex = 0;
            if (++dataIndex >= bytes)
                dataIndex = 0;
        }

        s_shaSeed.data[2] ^= (dword) &bytes;
        s_shaSeed.data[3] ^= (dword) bytes;
        s_shaSeed.data[4] ^= (dword) data;
    }

    // Hash seed
    ShaDigest digest;
    CryptDigest(kCryptSha, &digest, sizeof(s_shaSeed), &s_shaSeed);

    // Update output with contents of digest
    {
        unsigned src = 0;
        unsigned dst = 0;
        unsigned cur = 0;
        unsigned end = max(bytes, sizeof(digest));
        for (; cur < end; ++cur) {
            data[dst] ^= ((const byte *) &digest)[src];
            if (++src >= sizeof(digest))
                src = 0;
            if (++dst >= bytes)
                dst = 0;
        }
    }

    // Combine seed with digest
    s_shaSeed.data[0] ^= digest.data[0];
    s_shaSeed.data[1] ^= digest.data[1];
    s_shaSeed.data[2] ^= digest.data[2];
    s_shaSeed.data[3] ^= digest.data[3];
    s_shaSeed.data[4] ^= digest.data[4];
}

//============================================================================
void CryptHashPassword (
    const wchar username[],
    const wchar password[],
    ShaDigest * namePassHash
) {
    unsigned passlen = StrLen(password);
    unsigned userlen = StrLen(username);

    wchar * buffer = ALLOCA(wchar, passlen + userlen);
    StrCopy(buffer, password, passlen);
    StrCopy(buffer + passlen, username, userlen);
    StrLower(buffer + passlen); // lowercase the username

    CryptDigest(
        kCryptSha,
        namePassHash,
        (userlen + passlen) * sizeof(buffer[0]),
        buffer
    );
}

//============================================================================
void CryptHashPasswordChallenge (
    unsigned            clientChallenge,
    unsigned            serverChallenge,
    const ShaDigest &   namePassHash,
    ShaDigest *         challengeHash
) {
    #include <pshpack1.h>
    struct {
        dword       clientChallenge;
        dword       serverChallenge;
        ShaDigest   namePassHash;
    } buffer;
    #include <poppack.h>
    buffer.clientChallenge  = clientChallenge;
    buffer.serverChallenge  = serverChallenge;
    buffer.namePassHash     = namePassHash;
    CryptDigest(kCryptSha, challengeHash, sizeof(buffer), &buffer);
}

//============================================================================
void CryptCreateFastWeakChallenge (
    unsigned *  challenge,
    unsigned    val1,
    unsigned    val2
) {
    s_shaSeed.data[0] ^= TimeGetMs();                       // looping time
    s_shaSeed.data[0] ^= _rotl(s_shaSeed.data[0], 1);
    s_shaSeed.data[0] ^= (unsigned) TimeGetTime();          // global time
    s_shaSeed.data[0] ^= _rotl(s_shaSeed.data[0], 1);
    s_shaSeed.data[0] ^= *challenge;                        // unknown
    s_shaSeed.data[0] ^= _rotl(s_shaSeed.data[0], 1);
    s_shaSeed.data[0] ^= (unsigned) challenge;              // variable address
    s_shaSeed.data[0] ^= _rotl(s_shaSeed.data[0], 1);
    s_shaSeed.data[0] ^= val1;
    s_shaSeed.data[0] ^= _rotl(s_shaSeed.data[0], 1);
    s_shaSeed.data[0] ^= val2;
    *challenge        = s_shaSeed.data[0];
}

//============================================================================
void CryptEncrypt (
    CryptKey *      key,
    ARRAY(byte) *   dest,
    unsigned        sourceBytes,
    const void *    sourceData
) {
    switch (key->algorithm) {
        case kCryptRc4: {
            Rc4Codec(key, true, dest, sourceBytes, sourceData);
        }
        break;

        case kCryptRsa: // Not implemented; fall-thru to FATAL
//          RsaCodec(key, true, dest, sourceBytes, sourceData);
//      break;

        DEFAULT_FATAL(key->algorithm);
    }
}

//============================================================================
void CryptEncrypt (
    CryptKey *      key,
    unsigned        bytes,
    void *          data
) {
    ASSERT(1 == CryptKeyGetBlockSize(key));

    switch (key->algorithm) {
        case kCryptRc4: {
            Rc4Codec(key, true, bytes, data);
        }
        break;

        case kCryptRsa: // Not implemented; fall-thru to FATAL
//          RsaCodec(key, true, dest, sourceBytes, sourceData);
//      break;

        DEFAULT_FATAL(key->algorithm);
    }
}

//============================================================================
void CryptDecrypt (
    CryptKey *      key,
    ARRAY(byte) *   dest,
    unsigned        sourceBytes,
    const void *    sourceData
) {
    switch (key->algorithm) {
        case kCryptRc4: {
            Rc4Codec(key, false, dest, sourceBytes, sourceData);
        }
        break;

        case kCryptRsa: // Not implemented; fall-thru to FATAL
//          RsaCodec(key, false, dest, sourceBytes, sourceData);
//      break;

        DEFAULT_FATAL(key->algorithm);
    }
}

//============================================================================
void CryptDecrypt (
    CryptKey *      key,
    unsigned        bytes,
    void *          data
) {
    ASSERT(1 == CryptKeyGetBlockSize(key));

    switch (key->algorithm) {
        case kCryptRc4: {
            Rc4Codec(key, false, bytes, data);
        }
        break;

        case kCryptRsa: // Not implemented; fall-thru to FATAL
//          RsaCodec(key, false, dest, sourceBytes, sourceData);
//      break;

        DEFAULT_FATAL(key->algorithm);
    }
}