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Trying to create RSA signature with Python from C # working code

I am using another user's code to create the RSA signature used for verification in xbox 360 storage files. The code reads the necessary values ​​from the files and generates the signature correctly.

The code:

    byte[] xHash=null;
    RSAParameters xParams = new RSAParameters();
    br.BaseStream.Position = 0x1A8;
    xParams.D = br.ReadBytes(0x80);
    xParams.Exponent = br.ReadBytes(0x4);
    xParams.Modulus = br.ReadBytes(0x80);
    xParams.P = br.ReadBytes(0x40);
    xParams.Q = br.ReadBytes(0x40);
    xParams.DP = br.ReadBytes(0x40);
    xParams.DQ = br.ReadBytes(0x40);
    xParams.InverseQ = br.ReadBytes(0x40);
    br.close();

    br=new BinaryReader(File.OpenRead(f));
    br.BaseStream.Position=0x22c;
    xHash = new SHA1CryptoServiceProvider().ComputeHash(br.ReadBytes(0x118));
    byte[] xrsa=SignatureGenerate(xParams, xHash);

public static byte[] SignatureGenerate(RSAParameters xParam, byte[] xHash)
        {
            RSACryptoServiceProvider xRSACrypto = new RSACryptoServiceProvider();
            RSAPKCS1SignatureFormatter xRSASigFormat = new RSAPKCS1SignatureFormatter();
            xRSACrypto.ImportParameters(xParam);
            xRSASigFormat.SetHashAlgorithm("SHA1");
            xRSASigFormat.SetKey(xRSACrypto);
            return xRSASigFormat.CreateSignature(xHash);

        }

I am trying to end up with what's in xrsa, but using Python. I installed pycrypto and I am looking at the documentation, but I still don't see anything obvious. Firstly, RSA.construct from Crypto.PublicKey accepts only six parameters, but not indicators 1 and 2 (DP and DQ). In addition, the entries must be long. In C # code, the values ​​were 128 and 64 bytes in length, not 4 bytes.

I know this may seem painfully obvious, but I have no idea what I need to do.

I am working with Python 2.7.3

edit: "", , sha1 0x118 , .

edit: , , , . - #. # SHA1. , Python?

+1
2

ok, first: long python 4 . python, long , 128- . :

long_value = long(string_value.decode('hex'), 16)
# maybe someone knows a better way?

, DER? , :

from Crypto.PublicKey import RSA
with open("keyfile", "rb") as f:
    key = RSA.importKey(f.read())

, , PEM DER, . , RSA.construct , u 1/p % q (where p > q). , , , , .

+2

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