/// <summary> /// Generate an enveloped object that contains a CMS Enveloped Data /// object using the passed in key generator. /// </summary> private CmsEnvelopedData Generate( CmsProcessable content, string encryptionOid, CipherKeyGenerator keyGen) { AlgorithmIdentifier encAlgId = null; KeyParameter encKey; Asn1OctetString encContent; try { byte[] encKeyBytes = keyGen.GenerateKey(); encKey = ParameterUtilities.CreateKeyParameter(encryptionOid, encKeyBytes); Asn1Encodable asn1Params = GenerateAsn1Parameters(encryptionOid, encKeyBytes); ICipherParameters cipherParameters; encAlgId = GetAlgorithmIdentifier( encryptionOid, encKey, asn1Params, out cipherParameters); IBufferedCipher cipher = CipherUtilities.GetCipher(encryptionOid); cipher.Init(true, new ParametersWithRandom(cipherParameters, rand)); MemoryStream bOut = new MemoryStream(); CipherStream cOut = new CipherStream(bOut, null, cipher); content.Write(cOut); cOut.Dispose(); encContent = new BerOctetString(bOut.ToArray()); } 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); } } EncryptedContentInfo eci = new EncryptedContentInfo( CmsObjectIdentifiers.Data, encAlgId, encContent); Asn1Set unprotectedAttrSet = null; if (unprotectedAttributeGenerator != null) { Asn1.Cms.AttributeTable attrTable = unprotectedAttributeGenerator.GetAttributes(Platform.CreateHashtable()); unprotectedAttrSet = new BerSet(attrTable.ToAsn1EncodableVector()); } ContentInfo contentInfo = new ContentInfo( CmsObjectIdentifiers.EnvelopedData, new EnvelopedData(null, new DerSet(recipientInfos), eci, unprotectedAttrSet)); return new CmsEnvelopedData(contentInfo); }
/// <summary> /// Generate an enveloped object that contains an CMS Enveloped Data /// object using the passed in key generator. /// </summary> private Stream Open( Stream outStream, string encryptionOid, CipherKeyGenerator keyGen) { byte[] encKeyBytes = keyGen.GenerateKey(); KeyParameter encKey = ParameterUtilities.CreateKeyParameter(encryptionOid, encKeyBytes); Asn1Encodable asn1Params = GenerateAsn1Parameters(encryptionOid, encKeyBytes); ICipherParameters cipherParameters; AlgorithmIdentifier encAlgID = GetAlgorithmIdentifier( encryptionOid, encKey, asn1Params, out cipherParameters); 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); } } return Open(outStream, encAlgID, cipherParameters, recipientInfos); }
/** * 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(); Stream mOut = new TeeOutputStream(bOut, new MacOutputStream(mac)); content.Write(mOut); mOut.Dispose(); bOut.Dispose(); encContent = new BerOctetString(bOut.ToArray()); byte[] macOctets = MacUtilities.DoFinal(mac); 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); }