/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * 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 android.security.net.config;

import java.net.Socket;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.List;

import javax.net.ssl.SSLSocket;
import javax.net.ssl.SSLEngine;
import javax.net.ssl.SSLSession;
import javax.net.ssl.X509ExtendedTrustManager;

X509ExtendedTrustManager based on an ApplicationConfig. 
This trust manager delegates to the specific trust manager for the hostname being used for the connection (See ApplicationConfig.getConfigForHostname(String) and NetworkSecurityTrustManager).
 Note that if the ApplicationConfig has per-domain configurations the hostname aware #checkServerTrusted(X509Certificate[], String String) must be used instead of the normal non-aware call. 
@hide
/**
 * {@link X509ExtendedTrustManager} based on an {@link ApplicationConfig}.
 *
 * <p>This trust manager delegates to the specific trust manager for the hostname being used for
 * the connection (See {@link ApplicationConfig#getConfigForHostname(String)} and
 * {@link NetworkSecurityTrustManager}).</p>
 *
 * Note that if the {@code ApplicationConfig} has per-domain configurations the hostname aware
 * {@link #checkServerTrusted(X509Certificate[], String String)} must be used instead of the normal
 * non-aware call.
 * @hide */
public class RootTrustManager extends X509ExtendedTrustManager {
    private final ApplicationConfig mConfig;

    public RootTrustManager(ApplicationConfig config) {
        if (config == null) {
            throw new NullPointerException("config must not be null");
        }
        mConfig = config;
    }

    @Override
    public void checkClientTrusted(X509Certificate[] chain, String authType)
            throws CertificateException {
        // Use the default configuration for all client authentication. Domain specific configs are
        // only for use in checking server trust not client trust.
        NetworkSecurityConfig config = mConfig.getConfigForHostname("");
        config.getTrustManager().checkClientTrusted(chain, authType);
    }

    @Override
    public void checkClientTrusted(X509Certificate[] certs, String authType, Socket socket)
            throws CertificateException {
        // Use the default configuration for all client authentication. Domain specific configs are
        // only for use in checking server trust not client trust.
        NetworkSecurityConfig config = mConfig.getConfigForHostname("");
        config.getTrustManager().checkClientTrusted(certs, authType, socket);
    }

    @Override
    public void checkClientTrusted(X509Certificate[] certs, String authType, SSLEngine engine)
            throws CertificateException {
        // Use the default configuration for all client authentication. Domain specific configs are
        // only for use in checking server trust not client trust.
        NetworkSecurityConfig config = mConfig.getConfigForHostname("");
        config.getTrustManager().checkClientTrusted(certs, authType, engine);
    }

    @Override
    public void checkServerTrusted(X509Certificate[] certs, String authType, Socket socket)
            throws CertificateException {
        if (socket instanceof SSLSocket) {
            SSLSocket sslSocket = (SSLSocket) socket;
            SSLSession session = sslSocket.getHandshakeSession();
            if (session == null) {
                throw new CertificateException("Not in handshake; no session available");
            }
            String host = session.getPeerHost();
            NetworkSecurityConfig config = mConfig.getConfigForHostname(host);
            config.getTrustManager().checkServerTrusted(certs, authType, socket);
        } else {
            // Not an SSLSocket, use the hostname unaware checkServerTrusted.
            checkServerTrusted(certs, authType);
        }
    }

    @Override
    public void checkServerTrusted(X509Certificate[] certs, String authType, SSLEngine engine)
            throws CertificateException {
        SSLSession session = engine.getHandshakeSession();
        if (session == null) {
            throw new CertificateException("Not in handshake; no session available");
        }
        String host = session.getPeerHost();
        NetworkSecurityConfig config = mConfig.getConfigForHostname(host);
        config.getTrustManager().checkServerTrusted(certs, authType, engine);
    }

    @Override
    public void checkServerTrusted(X509Certificate[] certs, String authType)
            throws CertificateException {
        if (mConfig.hasPerDomainConfigs()) {
            throw new CertificateException(
                    "Domain specific configurations require that hostname aware"
                    + " checkServerTrusted(X509Certificate[], String, String) is used");
        }
        NetworkSecurityConfig config = mConfig.getConfigForHostname("");
        config.getTrustManager().checkServerTrusted(certs, authType);
    }

    
Hostname aware version of checkServerTrusted(X509Certificate[], String). This interface is used by conscrypt and android.net.http.X509TrustManagerExtensions do not modify without modifying those callers. /**
     * Hostname aware version of {@link #checkServerTrusted(X509Certificate[], String)}.
     * This interface is used by conscrypt and android.net.http.X509TrustManagerExtensions do not
     * modify without modifying those callers.
     */
    public List<X509Certificate> checkServerTrusted(X509Certificate[] certs, String authType,
            String hostname) throws CertificateException {
        if (hostname == null && mConfig.hasPerDomainConfigs()) {
            throw new CertificateException(
                    "Domain specific configurations require that the hostname be provided");
        }
        NetworkSecurityConfig config = mConfig.getConfigForHostname(hostname);
        return config.getTrustManager().checkServerTrusted(certs, authType, hostname);
    }

    @Override
    public X509Certificate[] getAcceptedIssuers() {
        // getAcceptedIssuers is meant to be used to determine which trust anchors the server will
        // accept when verifying clients. Domain specific configs are only for use in checking
        // server trust not client trust so use the default config.
        NetworkSecurityConfig config = mConfig.getConfigForHostname("");
        return config.getTrustManager().getAcceptedIssuers();
    }

    
Returns true if this trust manager uses the same trust configuration for the provided hostnames. 
This is required by android.net.http.X509TrustManagerExtensions.
/**
     * Returns {@code true} if this trust manager uses the same trust configuration for the provided
     * hostnames.
     *
     * <p>This is required by android.net.http.X509TrustManagerExtensions.
     */
    public boolean isSameTrustConfiguration(String hostname1, String hostname2) {
        return mConfig.getConfigForHostname(hostname1)
                .equals(mConfig.getConfigForHostname(hostname2));
    }
}