/// <exception cref="System.IO.IOException"/>
/// <exception cref="Org.BouncyCastle.Security.GeneralSecurityException"/>
internal static DERForRecipientParams CalculateDERForRecipientParams(byte[] @in)
{
String s = "1.2.840.113549.3.2";
DERForRecipientParams parameters = new DERForRecipientParams();
byte[] outp = new byte[100];
DerObjectIdentifier derob = new DerObjectIdentifier(s);
byte[] abyte0 = IVGenerator.GetIV(16); // keyp
IBufferedCipher cf = CipherUtilities.GetCipher(derob);
KeyParameter kp = new KeyParameter(abyte0);
byte[] iv = IVGenerator.GetIV(cf.GetBlockSize());
ParametersWithIV piv = new ParametersWithIV(kp, iv);
cf.Init(true, piv);
int len = cf.DoFinal(@in, outp, 0);
byte[] abyte1 = new byte[len];
Array.Copy(outp, 0, abyte1, 0, len);
Asn1EncodableVector ev = new Asn1EncodableVector();
ev.Add(new DerInteger(58));
ev.Add(new DerOctetString(iv));
DerSequence seq = new DerSequence(ev);
parameters.abyte0 = abyte0;
parameters.abyte1 = abyte1;
parameters.algorithmIdentifier = new AlgorithmIdentifier(derob, seq);
return(parameters);
}
internal static DERForRecipientParams CalculateDERForRecipientParams(byte[] @in)
{
/*
* According to ISO 32000-2 (7.6.5.3 Public-key encryption algorithms) RC-2 algorithm is outdated
* and should be replaced with a safer one 256-bit AES-CBC:
* The algorithms that shall be used to encrypt the enveloped data in the CMS object are:
* - RC4 with key lengths up to 256-bits (deprecated);
* - DES, Triple DES, RC2 with key lengths up to 128 bits (deprecated);
* - 128-bit AES in Cipher Block Chaining (CBC) mode (deprecated);
* - 192-bit AES in CBC mode (deprecated);
* - 256-bit AES in CBC mode.
*/
String s = "1.2.840.113549.3.2";
DERForRecipientParams parameters = new DERForRecipientParams();
byte[] outp = new byte[100];
DerObjectIdentifier derob = new DerObjectIdentifier(s);
// keyp
byte[] abyte0 = IVGenerator.GetIV(16);
IBufferedCipher cf = CipherUtilities.GetCipher(derob);
KeyParameter kp = new KeyParameter(abyte0);
byte[] iv = IVGenerator.GetIV(cf.GetBlockSize());
ParametersWithIV piv = new ParametersWithIV(kp, iv);
cf.Init(true, piv);
int len = cf.DoFinal(@in, outp, 0);
byte[] abyte1 = new byte[len];
Array.Copy(outp, 0, abyte1, 0, len);
Asn1EncodableVector ev = new Asn1EncodableVector();
ev.Add(new DerInteger(58));
ev.Add(new DerOctetString(iv));
DerSequence seq = new DerSequence(ev);
parameters.abyte0 = abyte0;
parameters.abyte1 = abyte1;
parameters.algorithmIdentifier = new AlgorithmIdentifier(derob, seq);
return(parameters);
}
