Added MaterialsDescription to Encryption Materials (note: encryption context and materials description will be treated as different

Author: Anirav Kareddy

src/main/java/software/amazon/encryption/s3/materials/EncryptionMaterials.java

@@ -27,6 +27,7 @@ final public class EncryptionMaterials implements CryptographicMaterials {
     // Additional information passed into encrypted that is required on decryption as well
     // Should NOT contain sensitive information
     private final Map<String, String> _encryptionContext;
+    private final MaterialsDescription _materialsDescription;
 
     private final List<EncryptedDataKey> _encryptedDataKeys;
     private final byte[] _plaintextDataKey;
@@ -43,6 +44,7 @@ private EncryptionMaterials(Builder builder) {
         this._cryptoProvider = builder._cryptoProvider;
         this._plaintextLength = builder._plaintextLength;
         this._ciphertextLength = _plaintextLength + _algorithmSuite.cipherTagLengthBytes();
+        this._materialsDescription = builder._materialsDescription;
     }
 
     static public Builder builder() {
@@ -101,6 +103,9 @@ public Provider cryptoProvider() {
         return _cryptoProvider;
     }
 
+    public MaterialsDescription materialsDescription() {
+        return _materialsDescription;
+    }
     @Override
     public CipherMode cipherMode() {
         return CipherMode.ENCRYPT;
@@ -119,6 +124,7 @@ public Builder toBuilder() {
                 .encryptedDataKeys(_encryptedDataKeys)
                 .plaintextDataKey(_plaintextDataKey)
                 .cryptoProvider(_cryptoProvider)
+                .materialsDescription(_materialsDescription)
                 .plaintextLength(_plaintextLength);
     }
 
@@ -132,6 +138,7 @@ static public class Builder {
         private byte[] _plaintextDataKey = null;
         private long _plaintextLength = -1;
         private Provider _cryptoProvider = null;
+        private MaterialsDescription _materialsDescription;
 
         private Builder() {
         }
@@ -145,7 +152,10 @@ public Builder algorithmSuite(AlgorithmSuite algorithmSuite) {
             _algorithmSuite = algorithmSuite;
             return this;
         }
-
+        public Builder materialsDescription(MaterialsDescription materialsDescription) {
+            _materialsDescription = materialsDescription;
+            return this;
+        }
         public Builder encryptionContext(Map<String, String> encryptionContext) {
             _encryptionContext = encryptionContext == null
                     ? Collections.emptyMap()