public static RSA FromCapiKeyBlob(byte[] blob)
{
return(CryptoConvert.FromCapiKeyBlob(blob, 0));
}
private static RSA FromCapiPrivateKeyBlob(byte[] blob, int offset)
{
RSAParameters parameters = default(RSAParameters);
try
{
if (blob[offset] != 7 || blob[offset + 1] != 2 || blob[offset + 2] != 0 || blob[offset + 3] != 0 || CryptoConvert.ToUInt32LE(blob, offset + 8) != 843141970u)
{
throw new CryptographicException("Invalid blob header");
}
int num = CryptoConvert.ToInt32LE(blob, offset + 12);
byte[] array = new byte[4];
Buffer.BlockCopy(blob, offset + 16, array, 0, 4);
Array.Reverse(array);
parameters.Exponent = CryptoConvert.Trim(array);
int num2 = offset + 20;
int num3 = num >> 3;
parameters.Modulus = new byte[num3];
Buffer.BlockCopy(blob, num2, parameters.Modulus, 0, num3);
Array.Reverse(parameters.Modulus);
num2 += num3;
int num4 = num3 >> 1;
parameters.P = new byte[num4];
Buffer.BlockCopy(blob, num2, parameters.P, 0, num4);
Array.Reverse(parameters.P);
num2 += num4;
parameters.Q = new byte[num4];
Buffer.BlockCopy(blob, num2, parameters.Q, 0, num4);
Array.Reverse(parameters.Q);
num2 += num4;
parameters.DP = new byte[num4];
Buffer.BlockCopy(blob, num2, parameters.DP, 0, num4);
Array.Reverse(parameters.DP);
num2 += num4;
parameters.DQ = new byte[num4];
Buffer.BlockCopy(blob, num2, parameters.DQ, 0, num4);
Array.Reverse(parameters.DQ);
num2 += num4;
parameters.InverseQ = new byte[num4];
Buffer.BlockCopy(blob, num2, parameters.InverseQ, 0, num4);
Array.Reverse(parameters.InverseQ);
num2 += num4;
parameters.D = new byte[num3];
if (num2 + num3 + offset <= blob.Length)
{
Buffer.BlockCopy(blob, num2, parameters.D, 0, num3);
Array.Reverse(parameters.D);
}
}
catch (Exception inner)
{
throw new CryptographicException("Invalid blob.", inner);
}
RSA rSA = null;
try
{
rSA = RSA.Create();
rSA.ImportParameters(parameters);
}
catch (CryptographicException)
{
bool flag = false;
try
{
rSA = new RSACryptoServiceProvider(new CspParameters
{
Flags = CspProviderFlags.UseMachineKeyStore
});
rSA.ImportParameters(parameters);
}
catch
{
flag = true;
}
if (flag)
{
throw;
}
}
return(rSA);
}
private static RSA FromCapiPublicKeyBlob(byte[] blob, int offset)
{
RSA result;
try
{
if (blob[offset] != 6 || blob[offset + 1] != 2 || blob[offset + 2] != 0 || blob[offset + 3] != 0 || CryptoConvert.ToUInt32LE(blob, offset + 8) != 826364754u)
{
throw new CryptographicException("Invalid blob header");
}
int num = CryptoConvert.ToInt32LE(blob, offset + 12);
RSAParameters parameters = default(RSAParameters);
parameters.Exponent = new byte[3];
parameters.Exponent[0] = blob[offset + 18];
parameters.Exponent[1] = blob[offset + 17];
parameters.Exponent[2] = blob[offset + 16];
int srcOffset = offset + 20;
int num2 = num >> 3;
parameters.Modulus = new byte[num2];
Buffer.BlockCopy(blob, srcOffset, parameters.Modulus, 0, num2);
Array.Reverse(parameters.Modulus);
RSA rSA = null;
try
{
rSA = RSA.Create();
rSA.ImportParameters(parameters);
}
catch (CryptographicException)
{
rSA = new RSACryptoServiceProvider(new CspParameters
{
Flags = CspProviderFlags.UseMachineKeyStore
});
rSA.ImportParameters(parameters);
}
result = rSA;
}
catch (Exception inner)
{
throw new CryptographicException("Invalid blob.", inner);
}
return(result);
}