crc

nt CheckSn(const char* input)
{
    //Encrypted key for RC4;
    int k[24] = {
    -2028,
-1927,
-1978,
2014,
1964,
2047,
-2011,
2019,
1988,
-2022,
2020,
-2020,
-2021,
1991,
1992,
-1968,
-2025,
2012,
-1964,
-1964,
1944,
-2012,
1990,
1993,
    };
    char kbuff[24];
    for (int i = 0; i < sizeof(kbuff); i++)
    {
        kbuff[i] = (char)0x7c9 ^ k[i];
    }

    char* kDec = rc4.Decrypt(kbuff, input);

    //Genrate RSA seed
    int seed = 0; //RSA seed
    for (int i = 0; i < 24; i++)
    {
        seed ^= (int)kDec[i] << 8;
    }

    //Encrypted flag
    unsigned __int64 flEnc[38] = {
1366097814,
2120983132,
11313650,
11313650,
1147720706,
1381141506,
534044772,
2120983132,
11313650,
1000603513,
1147720706,
2141013828,
2120983132,
1381141506,
166339272,
397371820,
1381141506,
2141013828,
1424449630,
1381141506,
336182013,
1303618044,
584361135,
1381141506,
534044772,
1147720706,
336182013,
11313650,
1273651409,
1381141506,
1828599282,
1273651409,
1273651409,
1424449630,
303606192,
1732470655,
1925038450,
    };

    //RSA
    RSA_PARAM r;
    r = RsaGetParam(seed);
    char decoded[38];
    for (int i = 0; i < sizeof(decoded); i++)
    {
        decoded[i] = (char)(PowMod(flEnc[i], r.d, r.n));
    }
    char* flDec = (char*)decoded;

    if (Crc32(flDec, 38, 0x7c9) == -622969371)
    {
        strcpy(flagCorrect, flDec);
        return 1;
    }

    return 0;
}