com.google.crypto.tink.signature.PublicKeyVerifyWrapper Maven / Gradle / Ivy
Show all versions of tink-android Show documentation
// Copyright 2017 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
////////////////////////////////////////////////////////////////////////////////
package com.google.crypto.tink.signature;
import com.google.crypto.tink.CryptoFormat;
import com.google.crypto.tink.PublicKeyVerify;
import com.google.crypto.tink.internal.LegacyProtoKey;
import com.google.crypto.tink.internal.MonitoringClient;
import com.google.crypto.tink.internal.MonitoringKeysetInfo;
import com.google.crypto.tink.internal.MonitoringUtil;
import com.google.crypto.tink.internal.MutableMonitoringRegistry;
import com.google.crypto.tink.internal.MutablePrimitiveRegistry;
import com.google.crypto.tink.internal.PrimitiveConstructor;
import com.google.crypto.tink.internal.PrimitiveRegistry;
import com.google.crypto.tink.internal.PrimitiveSet;
import com.google.crypto.tink.internal.PrimitiveWrapper;
import com.google.crypto.tink.signature.internal.LegacyFullVerify;
import java.security.GeneralSecurityException;
import java.util.Arrays;
import java.util.List;
/**
* The implementation of {@code PrimitiveWrapper}.
*
* The returned primitive works with a keyset (rather than a single key). To verify a signature,
* the primitive uses the prefix of the signature to efficiently select the right key in the set. If
* there is no key associated with the prefix or if the keys associated with the prefix do not work,
* the primitive tries all keys with {@link com.google.crypto.tink.proto.OutputPrefixType#RAW}.
*
* @since 1.0.0
*/
public class PublicKeyVerifyWrapper implements PrimitiveWrapper {
private static final PublicKeyVerifyWrapper WRAPPER = new PublicKeyVerifyWrapper();
private static final PrimitiveConstructor
LEGACY_PRIMITIVE_CONSTRUCTOR =
PrimitiveConstructor.create(
LegacyFullVerify::create, LegacyProtoKey.class, PublicKeyVerify.class);
private static class WrappedPublicKeyVerify implements PublicKeyVerify {
private final PrimitiveSet primitives;
private final MonitoringClient.Logger monitoringLogger;
public WrappedPublicKeyVerify(PrimitiveSet primitives) {
this.primitives = primitives;
if (primitives.hasAnnotations()) {
MonitoringClient client = MutableMonitoringRegistry.globalInstance().getMonitoringClient();
MonitoringKeysetInfo keysetInfo = MonitoringUtil.getMonitoringKeysetInfo(primitives);
this.monitoringLogger = client.createLogger(keysetInfo, "public_key_verify", "verify");
} else {
this.monitoringLogger = MonitoringUtil.DO_NOTHING_LOGGER;
}
}
@Override
public void verify(final byte[] signature, final byte[] data) throws GeneralSecurityException {
if (signature.length <= CryptoFormat.NON_RAW_PREFIX_SIZE) {
// This also rejects raw signatures with size of 4 bytes or fewer. We're not aware of any
// schemes that output signatures that small.
monitoringLogger.logFailure();
throw new GeneralSecurityException("signature too short");
}
byte[] prefix = Arrays.copyOf(signature, CryptoFormat.NON_RAW_PREFIX_SIZE);
List> entries = primitives.getPrimitive(prefix);
for (PrimitiveSet.Entry entry : entries) {
try {
entry.getFullPrimitive().verify(signature, data);
monitoringLogger.log(entry.getKeyId(), data.length);
// If there is no exception, the signature is valid and we can return.
return;
} catch (GeneralSecurityException e) {
// Ignored as we want to continue verification with the remaining keys.
}
}
// None "non-raw" key matched, so let's try the raw keys (if any exist).
entries = primitives.getRawPrimitives();
for (PrimitiveSet.Entry entry : entries) {
try {
entry.getFullPrimitive().verify(signature, data);
monitoringLogger.log(entry.getKeyId(), data.length);
// If there is no exception, the signature is valid and we can return.
return;
} catch (GeneralSecurityException e) {
// Ignored as we want to continue verification with raw keys.
}
}
// nothing works.
monitoringLogger.logFailure();
throw new GeneralSecurityException("invalid signature");
}
}
@Override
public PublicKeyVerify wrap(final PrimitiveSet primitives) {
return new WrappedPublicKeyVerify(primitives);
}
@Override
public Class getPrimitiveClass() {
return PublicKeyVerify.class;
}
@Override
public Class getInputPrimitiveClass() {
return PublicKeyVerify.class;
}
/**
* Register the wrapper within the registry.
*
* This is required for calls to {@link Keyset.getPrimitive} with a {@link PublicKeyVerify}
* argument.
*/
static void register() throws GeneralSecurityException {
MutablePrimitiveRegistry.globalInstance().registerPrimitiveWrapper(WRAPPER);
MutablePrimitiveRegistry.globalInstance()
.registerPrimitiveConstructor(LEGACY_PRIMITIVE_CONSTRUCTOR);
}
/**
* registerToInternalPrimitiveRegistry is a non-public method (it takes an argument of an
* internal-only type) registering an instance of {@code PublicKeyVerifyWrapper} to the provided
* {@code PrimitiveRegistry#Builder}.
*/
public static void registerToInternalPrimitiveRegistry(
PrimitiveRegistry.Builder primitiveRegistryBuilder) throws GeneralSecurityException {
primitiveRegistryBuilder.registerPrimitiveWrapper(WRAPPER);
}
}