Amazon.S3.Encryption.AmazonS3EncryptionClient.GenerateEncryptedUploadPartRequest C# (CSharp) Метод

        private void GenerateEncryptedUploadPartRequest(UploadPartRequest request)
        {
            string uploadID = request.UploadId;

            UploadPartEncryptionContext contextForEncryption = currentMultiPartUploadKeys[uploadID];
            byte[] envelopeKey = contextForEncryption.EnvelopeKey;
            byte[] IV = contextForEncryption.NextIV;

            EncryptionInstructions instructions = new EncryptionInstructions(EncryptionMaterials.EmptyMaterialsDescription, envelopeKey, IV);

            if (request.IsLastPart == false)
            {
                if (contextForEncryption.IsFinalPart == true)
                    throw new AmazonClientException("Last part has already been processed, cannot upload this as the last part");

                if (request.PartNumber < contextForEncryption.PartNumber)
                    throw new AmazonClientException("Upload Parts must in correct sequence");

                request.InputStream = EncryptionUtils.EncryptUploadPartRequestUsingInstructions(request.InputStream, instructions);
                contextForEncryption.PartNumber = request.PartNumber;
            }
            else
            {
                request.InputStream = EncryptionUtils.EncryptRequestUsingInstruction(request.InputStream, instructions);
                contextForEncryption.IsFinalPart = true;
            }
            request.RequestState.Add(S3CryptoStream, request.InputStream);
        }