org.springframework.cloud.gateway.handler.predicate.RemoteAddrRoutePredicateFactory.java Source code

Introduction

Here is the source code for org.springframework.cloud.gateway.handler.predicate.RemoteAddrRoutePredicateFactory.java

Source

/*
 * Copyright 2013-2019 the original author or authors.
 *
 * 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
 *
 *      https://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.springframework.cloud.gateway.handler.predicate;

import java.net.InetSocketAddress;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.function.Predicate;

import javax.validation.constraints.NotEmpty;
import javax.validation.constraints.NotNull;

import io.netty.handler.ipfilter.IpFilterRuleType;
import io.netty.handler.ipfilter.IpSubnetFilterRule;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.cloud.gateway.support.ipresolver.RemoteAddressResolver;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.server.ServerWebExchange;

import static org.springframework.cloud.gateway.support.ShortcutConfigurable.ShortcutType.GATHER_LIST;

/**
 * @author Spencer Gibb
 */
public class RemoteAddrRoutePredicateFactory
        extends AbstractRoutePredicateFactory<RemoteAddrRoutePredicateFactory.Config> {

    private static final Log log = LogFactory.getLog(RemoteAddrRoutePredicateFactory.class);

    public RemoteAddrRoutePredicateFactory() {
        super(Config.class);
    }

    @Override
    public ShortcutType shortcutType() {
        return GATHER_LIST;
    }

    @Override
    public List<String> shortcutFieldOrder() {
        return Collections.singletonList("sources");
    }

    @NotNull
    private List<IpSubnetFilterRule> convert(List<String> values) {
        List<IpSubnetFilterRule> sources = new ArrayList<>();
        for (String arg : values) {
            addSource(sources, arg);
        }
        return sources;
    }

    @Override
    public Predicate<ServerWebExchange> apply(Config config) {
        List<IpSubnetFilterRule> sources = convert(config.sources);

        return exchange -> {
            InetSocketAddress remoteAddress = config.remoteAddressResolver.resolve(exchange);
            if (remoteAddress != null && remoteAddress.getAddress() != null) {
                String hostAddress = remoteAddress.getAddress().getHostAddress();
                String host = exchange.getRequest().getURI().getHost();

                if (log.isDebugEnabled() && !hostAddress.equals(host)) {
                    log.debug("Remote addresses didn't match " + hostAddress + " != " + host);
                }

                for (IpSubnetFilterRule source : sources) {
                    if (source.matches(remoteAddress)) {
                        return true;
                    }
                }
            }

            return false;
        };
    }

    private void addSource(List<IpSubnetFilterRule> sources, String source) {
        if (!source.contains("/")) { // no netmask, add default
            source = source + "/32";
        }

        String[] ipAddressCidrPrefix = source.split("/", 2);
        String ipAddress = ipAddressCidrPrefix[0];
        int cidrPrefix = Integer.parseInt(ipAddressCidrPrefix[1]);

        sources.add(new IpSubnetFilterRule(ipAddress, cidrPrefix, IpFilterRuleType.ACCEPT));
    }

    @Validated
    public static class Config {

        @NotEmpty
        private List<String> sources = new ArrayList<>();

        @NotNull
        private RemoteAddressResolver remoteAddressResolver = new RemoteAddressResolver() {
        };

        public List<String> getSources() {
            return sources;
        }

        public Config setSources(List<String> sources) {
            this.sources = sources;
            return this;
        }

        public Config setSources(String... sources) {
            this.sources = Arrays.asList(sources);
            return this;
        }

        public Config setRemoteAddressResolver(RemoteAddressResolver remoteAddressResolver) {
            this.remoteAddressResolver = remoteAddressResolver;
            return this;
        }

    }

}