org.opensaml.xmlsec.signature.support.impl.ChainingSignatureTrustEngine.java Source code

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Here is the source code for org.opensaml.xmlsec.signature.support.impl.ChainingSignatureTrustEngine.java

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/*
 * Licensed to the University Corporation for Advanced Internet Development, 
 * Inc. (UCAID) under one or more contributor license agreements.  See the 
 * NOTICE file distributed with this work for additional information regarding
 * copyright ownership. The UCAID licenses this file to You 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 org.opensaml.xmlsec.signature.support.impl;

import java.util.ArrayList;
import java.util.List;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

import net.shibboleth.utilities.java.support.annotation.constraint.NonnullElements;
import net.shibboleth.utilities.java.support.annotation.constraint.NotLive;
import net.shibboleth.utilities.java.support.annotation.constraint.Unmodifiable;
import net.shibboleth.utilities.java.support.logic.Constraint;
import net.shibboleth.utilities.java.support.resolver.CriteriaSet;

import org.opensaml.security.SecurityException;
import org.opensaml.security.credential.Credential;
import org.opensaml.xmlsec.keyinfo.KeyInfoCredentialResolver;
import org.opensaml.xmlsec.signature.Signature;
import org.opensaml.xmlsec.signature.support.SignatureTrustEngine;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.base.Predicates;
import com.google.common.collect.Collections2;
import com.google.common.collect.ImmutableList;

/**
 * Evaluate a signature in sequence using a chain of subordinate trust engines. If the signature may be established as
 * trusted by any of the subordinate engines, the token is considered trusted. Otherwise it is considered untrusted.
 */
public class ChainingSignatureTrustEngine implements SignatureTrustEngine {

    /** Class logger. */
    @Nonnull
    private final Logger log = LoggerFactory.getLogger(ChainingSignatureTrustEngine.class);

    /** The chain of subordinate trust engines. */
    @Nonnull
    @NonnullElements
    private List<SignatureTrustEngine> engines;

    /**
     *  Constructor. 
     *  
     *  @param chain the list of trust engines in the chain
     */
    public ChainingSignatureTrustEngine(@Nonnull @NonnullElements final List<SignatureTrustEngine> chain) {
        Constraint.isNotNull(chain, "SignatureTrustEngine list cannot be null");
        engines = new ArrayList<>(Collections2.filter(chain, Predicates.notNull()));
    }

    /**
     * Get the list of configured trust engines which constitute the trust evaluation chain.
     * 
     * @return the modifiable list of trust engines in the chain
     */
    @Nonnull
    @NonnullElements
    @Unmodifiable
    @NotLive
    public List<SignatureTrustEngine> getChain() {
        return ImmutableList.copyOf(engines);
    }

    /** {@inheritDoc} */
    @Override
    @Nullable
    public KeyInfoCredentialResolver getKeyInfoResolver() {
        // Chaining signature trust engine does not support an attached KeyInfoResolver
        return null;
    }

    /** {@inheritDoc} */
    @Override
    public boolean validate(@Nonnull final Signature token, @Nullable final CriteriaSet trustBasisCriteria)
            throws SecurityException {

        for (final SignatureTrustEngine engine : engines) {
            if (engine.validate(token, trustBasisCriteria)) {
                log.debug("Signature was trusted by chain member: {}", engine.getClass().getName());
                return true;
            }
        }
        return false;
    }

    /** {@inheritDoc} */
    @Override
    public boolean validate(@Nonnull final byte[] signature, @Nonnull final byte[] content,
            @Nonnull final String algorithmURI, @Nullable final CriteriaSet trustBasisCriteria,
            @Nonnull final Credential candidateCredential) throws SecurityException {

        for (final SignatureTrustEngine engine : engines) {
            if (engine.validate(signature, content, algorithmURI, trustBasisCriteria, candidateCredential)) {
                log.debug("Signature was trusted by chain member: {}", engine.getClass().getName());
                return true;
            }
        }
        return false;
    }

}