Example #1
0
            public override void Close()
            {
                macStream.Close();
                eiGen.Close();

                // [TODO] auth attributes go here
                byte[] macOctets = MacUtilities.DoFinal(macStream.WriteMac());
                authGen.AddObject(new DerOctetString(macOctets));
                // [TODO] unauth attributes go here

                authGen.Close();
                cGen.Close();
            }
        /**
         * generate an enveloped object that contains an CMS Enveloped Data
         * object using the given provider and the passed in key generator.
         */
        private CmsAuthenticatedData Generate(
            CmsProcessable content,
            string macOid,
            CipherKeyGenerator keyGen)
        {
            AlgorithmIdentifier macAlgId;
            KeyParameter        encKey;
            Asn1OctetString     encContent;
            Asn1OctetString     macResult;

            try
            {
                // FIXME Will this work for macs?
                byte[] encKeyBytes = keyGen.GenerateKey();
                encKey = ParameterUtilities.CreateKeyParameter(macOid, encKeyBytes);

                Asn1Encodable asn1Params = GenerateAsn1Parameters(macOid, encKeyBytes);

                ICipherParameters cipherParameters;
                macAlgId = GetAlgorithmIdentifier(
                    macOid, encKey, asn1Params, out cipherParameters);

                IMac mac = MacUtilities.GetMac(macOid);
                // TODO Confirm no ParametersWithRandom needed
                // FIXME Only passing key at the moment
//	            mac.Init(cipherParameters);
                mac.Init(encKey);

                MemoryStream bOut = new MemoryStream();
                MacStream    mOut = new MacStream(bOut, null, mac);

                content.Write(mOut);

                mOut.Close();
                bOut.Close();

                encContent = new BerOctetString(bOut.ToArray());

                byte[] macOctets = MacUtilities.DoFinal(mOut.WriteMac());
                macResult = new DerOctetString(macOctets);
            }
            catch (SecurityUtilityException e)
            {
                throw new CmsException("couldn't create cipher.", e);
            }
            catch (InvalidKeyException e)
            {
                throw new CmsException("key invalid in message.", e);
            }
            catch (IOException e)
            {
                throw new CmsException("exception decoding algorithm parameters.", e);
            }


            Asn1EncodableVector recipientInfos = new Asn1EncodableVector();

            foreach (RecipientInfoGenerator rig in recipientInfoGenerators)
            {
                try
                {
                    recipientInfos.Add(rig.Generate(encKey, rand));
                }
                catch (InvalidKeyException e)
                {
                    throw new CmsException("key inappropriate for algorithm.", e);
                }
                catch (GeneralSecurityException e)
                {
                    throw new CmsException("error making encrypted content.", e);
                }
            }

            ContentInfo eci = new ContentInfo(CmsObjectIdentifiers.Data, encContent);

            ContentInfo contentInfo = new ContentInfo(
                CmsObjectIdentifiers.AuthenticatedData,
                new AuthenticatedData(null, new DerSet(recipientInfos), macAlgId, null, eci, null, macResult, null));

            return(new CmsAuthenticatedData(contentInfo));
        }