public static byte[] RSA2048Decrypt(byte[] ciphertext, RSAKeyset keyset)
{
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
rsa.ImportParameters(new RSAParameters
{
P = keyset.Prime1,
Q = keyset.Prime2,
Exponent = keyset.PublicExponent,
Modulus = keyset.Modulus,
DP = keyset.Exponent1,
DQ = keyset.Exponent2,
InverseQ = keyset.Coefficient,
D = keyset.PrivateExponent
});
return(rsa.Decrypt(ciphertext, false));
}
/// <summary>
/// Sign the given SHA-256 hash with PKCS1 padding
/// </summary>
/// <param name="sha256Hash">Hash</param>
/// <param name="keyset">Keys to use</param>
/// <returns>RSA 2048 signature of the hash</returns>
public static byte[] RSA2048SignSha256(byte[] sha256Hash, RSAKeyset keyset)
{
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
rsa.ImportParameters(new RSAParameters
{
P = keyset.Prime1,
Q = keyset.Prime2,
Exponent = keyset.PublicExponent,
Modulus = keyset.Modulus,
DP = keyset.Exponent1,
DQ = keyset.Exponent2,
InverseQ = keyset.Coefficient,
D = keyset.PrivateExponent
});
return(rsa.SignHash(sha256Hash, CryptoConfig.MapNameToOID("SHA256")));
}
/// <summary>
/// From FPKG Code (sceSblPfsSetKeys): Turns the EEKPfs to an EKPfs
/// </summary>
public static byte[] DecryptEEKPfs(byte[] eekpfs, RSAKeyset keyset)
{
var @params = new RSAParameters
{
D = keyset.PrivateExponent,
DP = keyset.Exponent1,
DQ = keyset.Exponent2,
Exponent = keyset.PublicExponent,
InverseQ = keyset.Coefficient,
Modulus = keyset.Modulus,
P = keyset.Prime1,
Q = keyset.Prime2
};
using (var rsa = RSA.Create())
{
rsa.KeySize = 2048;
rsa.ImportParameters(@params);
return(rsa.DecryptValue(eekpfs));
}
}
