Move the SimpleParameters into LegacyProtoKey and rename it to Legacy…

…ProtoParametersNotForCreation.

This is useful in many contexts when one has a LegacyProtoKey. While one still cannot create a new key out of it, one can at least call toString() on the parameters object, which should be useful in other cases too.

Also this simplifies the constructor of a PrimitiveSet Entry.

PiperOrigin-RevId: 466319231

java_src/src/main/java/com/google/crypto/tink/PrimitiveSet.java

@@ -16,16 +16,13 @@
 
 package com.google.crypto.tink;
 
-import com.google.crypto.tink.annotations.Alpha;
-import com.google.crypto.tink.internal.LegacyProtoKey;
 import com.google.crypto.tink.internal.MutableSerializationRegistry;
 import com.google.crypto.tink.internal.ProtoKeySerialization;
 import com.google.crypto.tink.monitoring.MonitoringAnnotations;
 import com.google.crypto.tink.proto.KeyStatusType;
 import com.google.crypto.tink.proto.Keyset;
 import com.google.crypto.tink.proto.OutputPrefixType;
 import com.google.crypto.tink.subtle.Hex;
-import com.google.errorprone.annotations.Immutable;
 import java.security.GeneralSecurityException;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -57,51 +54,6 @@
  */
 public final class PrimitiveSet<P> {
 
-  // A simple implementation of Parameters.
-  // Consider renaming this class and moving it into internal. And use it in LegacyProtoKey.
-  @Immutable
-  @Alpha
-  private static class SimpleParameters extends Parameters {
-
-    private final String typeUrl;
-    private final OutputPrefixType outputPrefixType;
-
-    @Override
-    public boolean hasIdRequirement() {
-      return outputPrefixType != OutputPrefixType.RAW;
-    }
-
-    // This function is needed because LiteProto do not have a good toString function.
-    private static String outputPrefixToString(OutputPrefixType outputPrefixType) {
-      switch (outputPrefixType) {
-        case TINK:
-          return "TINK";
-        case LEGACY:
-          return "LEGACY";
-        case RAW:
-          return "RAW";
-        case CRUNCHY:
-          return "CRUNCHY";
-        default:
-          return "UNKNOWN";
-      }
-    }
-
-    /**
-     * Returns the string representation. The exact details are unspecified and subject to change.
-     */
-    @Override
-    public String toString() {
-      return String.format(
-          "(typeUrl=%s, outputPrefixType=%s)", typeUrl, outputPrefixToString(outputPrefixType));
-    }
-
-    private SimpleParameters(String typeUrl, OutputPrefixType outputPrefixType) {
-      this.typeUrl = typeUrl;
-      this.outputPrefixType = outputPrefixType;
-    }
-  }
-
   /**
    * A single entry in the set. In addition to the actual primitive it holds also some extra
    * information about the primitive.
@@ -119,23 +71,20 @@ public static final class Entry<P> {
     // The id of the key.
     private final int keyId;
     private final Key key;
-    private final Parameters parameters;
 
     Entry(
         P primitive,
         final byte[] identifier,
         KeyStatusType status,
         OutputPrefixType outputPrefixType,
         int keyId,
-        Key key,
-        Parameters parameters) {
+        Key key) {
       this.primitive = primitive;
       this.identifier = Arrays.copyOf(identifier, identifier.length);
       this.status = status;
       this.outputPrefixType = outputPrefixType;
       this.keyId = keyId;
       this.key = key;
-      this.parameters = parameters;
     }
 
     /**
@@ -174,7 +123,7 @@ public Key getKey() {
     }
 
     public Parameters getParameters() {
-      return parameters;
+      return key.getParameters();
     }
   }
 
@@ -195,21 +144,14 @@ private static <P> Entry<P> addEntryToMap(
                     key.getOutputPrefixType(),
                     idRequirement),
                 InsecureSecretKeyAccess.get());
-    Parameters parameters;
-    if (keyObject instanceof LegacyProtoKey) {
-      parameters = new SimpleParameters(key.getKeyData().getTypeUrl(), key.getOutputPrefixType());
-    } else {
-      parameters = keyObject.getParameters();
-    }
     Entry<P> entry =
         new Entry<P>(
             primitive,
             CryptoFormat.getOutputPrefix(key),
             key.getStatus(),
             key.getOutputPrefixType(),
             key.getKeyId(),
-            keyObject,
-            parameters);
+            keyObject);
     List<Entry<P>> list = new ArrayList<>();
     list.add(entry);
     // Cannot use byte[] as keys in hash map, convert to Prefix wrapper class.

java_src/src/main/java/com/google/crypto/tink/internal/BUILD.bazel

@@ -342,6 +342,7 @@ java_library(
     srcs = ["LegacyProtoKey.java"],
     deps = [
         ":proto_key_serialization",
+        "//proto:tink_java_proto",
         "//src/main/java/com/google/crypto/tink:key",
         "//src/main/java/com/google/crypto/tink:parameters",
         "//src/main/java/com/google/crypto/tink:secret_key_access",
@@ -356,6 +357,7 @@ android_library(
     srcs = ["LegacyProtoKey.java"],
     deps = [
         ":proto_key_serialization-android",
+        "//proto:tink_java_proto_lite",
         "//src/main/java/com/google/crypto/tink:key-android",
         "//src/main/java/com/google/crypto/tink:parameters-android",
         "//src/main/java/com/google/crypto/tink:secret_key_access-android",

java_src/src/main/java/com/google/crypto/tink/internal/LegacyProtoKey.java

@@ -19,6 +19,7 @@
 import com.google.crypto.tink.Key;
 import com.google.crypto.tink.Parameters;
 import com.google.crypto.tink.SecretKeyAccess;
+import com.google.crypto.tink.proto.OutputPrefixType;
 import com.google.crypto.tink.subtle.Bytes;
 import com.google.errorprone.annotations.Immutable;
 import java.security.GeneralSecurityException;
@@ -28,6 +29,53 @@
 /** Implements a Key for legacy types where no actual parser is present. */
 @Immutable
 public final class LegacyProtoKey extends Key {
+  /**
+   * An implementation of Parameters which is returned by LegacyProtoKey.
+   *
+   * <p>In contrast to LegacyProtoParameters, this cannot be used to create a new LegacyProtoKey
+   * object.
+   */
+  @Immutable
+  private static class LegacyProtoParametersNotForCreation extends Parameters {
+    private final String typeUrl;
+    private final OutputPrefixType outputPrefixType;
+
+    @Override
+    public boolean hasIdRequirement() {
+      return outputPrefixType != OutputPrefixType.RAW;
+    }
+
+    // This function is needed because LiteProto do not have a good toString function.
+    private static String outputPrefixToString(OutputPrefixType outputPrefixType) {
+      switch (outputPrefixType) {
+        case TINK:
+          return "TINK";
+        case LEGACY:
+          return "LEGACY";
+        case RAW:
+          return "RAW";
+        case CRUNCHY:
+          return "CRUNCHY";
+        default:
+          return "UNKNOWN";
+      }
+    }
+
+    /**
+     * Returns the string representation. The exact details are unspecified and subject to change.
+     */
+    @Override
+    public String toString() {
+      return String.format(
+          "(typeUrl=%s, outputPrefixType=%s)", typeUrl, outputPrefixToString(outputPrefixType));
+    }
+
+    private LegacyProtoParametersNotForCreation(String typeUrl, OutputPrefixType outputPrefixType) {
+      this.typeUrl = typeUrl;
+      this.outputPrefixType = outputPrefixType;
+    }
+  }
+
   private final ProtoKeySerialization serialization;
 
   private static void throwIfMissingAccess(
@@ -104,9 +152,15 @@ public ProtoKeySerialization getSerialization(@Nullable SecretKeyAccess access)
     return serialization;
   }
 
-  /** Unsupported. */
+  /**
+   * Returns a LegacyParametersNotForCreation object.
+   *
+   * <p>Note: this is different from the {@code LegacyProtoParameters} object which was used to
+   * create this key. One cannot use the returned object to create a new key.
+   */
   @Override
   public Parameters getParameters() {
-    throw new UnsupportedOperationException("Cannot get parameters on LegacyProtoKey");
+    return new LegacyProtoParametersNotForCreation(
+        serialization.getTypeUrl(), serialization.getOutputPrefixType());
   }
 }

java_src/src/test/java/com/google/crypto/tink/internal/LegacyProtoKeyTest.java

@@ -46,6 +46,22 @@ public void testLegacyProtoKeyCreate() throws Exception {
     assertThat(key.getSerialization(ACCESS)).isSameInstanceAs(serialization);
   }
 
+  @Test
+  public void testLegacyProtoKey_getParameters() throws Exception {
+    ProtoKeySerialization serialization =
+        ProtoKeySerialization.create(
+            "myTypeUrl",
+            ByteString.EMPTY,
+            KeyMaterialType.SYMMETRIC,
+            OutputPrefixType.RAW,
+            /*idRequirement = */ null);
+    LegacyProtoKey key = new LegacyProtoKey(serialization, ACCESS);
+    assertThat(key.getSerialization(ACCESS)).isSameInstanceAs(serialization);
+
+    assertThat(key.getParameters().toString()).contains("typeUrl=myTypeUrl");
+    assertThat(key.getParameters().toString()).contains("outputPrefixType=RAW");
+  }
+
   @Test
   public void testGetIdRequirementOrNull() throws Exception {
     // RAW