| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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.apache.hadoop.hdfs.server.datanode.web; |
| |
| import static io.netty.handler.codec.http.HttpHeaderNames.CONNECTION; |
| import static io.netty.handler.codec.http.HttpHeaderValues.CLOSE; |
| import static io.netty.handler.codec.http.HttpResponseStatus.INTERNAL_SERVER_ERROR; |
| import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1; |
| import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_WEBHDFS_REST_CSRF_ENABLED_DEFAULT; |
| import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_WEBHDFS_REST_CSRF_ENABLED_KEY; |
| |
| import java.util.Map; |
| |
| import javax.servlet.ServletException; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.security.http.RestCsrfPreventionFilter; |
| import org.apache.hadoop.security.http.RestCsrfPreventionFilter.HttpInteraction; |
| import org.slf4j.Logger; |
| |
| import io.netty.channel.ChannelFutureListener; |
| import io.netty.channel.ChannelHandler.Sharable; |
| import io.netty.channel.ChannelHandlerContext; |
| import io.netty.channel.SimpleChannelInboundHandler; |
| import io.netty.handler.codec.http.DefaultHttpResponse; |
| import io.netty.handler.codec.http.HttpRequest; |
| import io.netty.handler.codec.http.HttpResponseStatus; |
| import io.netty.util.ReferenceCountUtil; |
| |
| |
| /** |
| * Netty handler that integrates with the {@link RestCsrfPreventionFilter}. If |
| * the filter determines that the request is allowed, then this handler forwards |
| * the request to the next handler in the Netty pipeline. Otherwise, this |
| * handler drops the request and immediately sends an HTTP 400 response. |
| */ |
| @InterfaceAudience.Private |
| @Sharable |
| final class RestCsrfPreventionFilterHandler |
| extends SimpleChannelInboundHandler<HttpRequest> { |
| |
| private static final Logger LOG = DatanodeHttpServer.LOG; |
| |
| private final RestCsrfPreventionFilter restCsrfPreventionFilter; |
| |
| /** |
| * Creates a new RestCsrfPreventionFilterHandler. There will be a new |
| * instance created for each new Netty channel/pipeline serving a new request. |
| * To prevent the cost of repeated initialization of the filter, this |
| * constructor requires the caller to pass in a pre-built, fully initialized |
| * filter instance. The filter is stateless after initialization, so it can |
| * be shared across multiple Netty channels/pipelines. |
| * |
| * @param restCsrfPreventionFilter initialized filter |
| */ |
| RestCsrfPreventionFilterHandler( |
| RestCsrfPreventionFilter restCsrfPreventionFilter) { |
| if(restCsrfPreventionFilter == null) { |
| LOG.warn("Got null for restCsrfPreventionFilter - will not do any filtering."); |
| } |
| this.restCsrfPreventionFilter = restCsrfPreventionFilter; |
| } |
| |
| @Override |
| protected void channelRead0(final ChannelHandlerContext ctx, |
| final HttpRequest req) throws Exception { |
| if(restCsrfPreventionFilter != null) { |
| restCsrfPreventionFilter.handleHttpInteraction(new NettyHttpInteraction( |
| ctx, req)); |
| } else { |
| // we do not have a valid filter simply pass requests |
| new NettyHttpInteraction(ctx, req).proceed(); |
| } |
| } |
| |
| @Override |
| public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { |
| LOG.error("Exception in " + this.getClass().getSimpleName(), cause); |
| sendResponseAndClose(ctx, |
| new DefaultHttpResponse(HTTP_1_1, INTERNAL_SERVER_ERROR)); |
| } |
| |
| /** |
| * Finish handling this pipeline by writing a response with the |
| * "Connection: close" header, flushing, and scheduling a close of the |
| * connection. |
| * |
| * @param ctx context to receive the response |
| * @param resp response to send |
| */ |
| private static void sendResponseAndClose(ChannelHandlerContext ctx, |
| DefaultHttpResponse resp) { |
| resp.headers().set(CONNECTION, CLOSE); |
| ctx.writeAndFlush(resp).addListener(ChannelFutureListener.CLOSE); |
| } |
| |
| /** |
| * {@link HttpInteraction} implementation for use in a Netty pipeline. |
| */ |
| private static final class NettyHttpInteraction implements HttpInteraction { |
| |
| private final ChannelHandlerContext ctx; |
| private final HttpRequest req; |
| |
| /** |
| * Creates a new NettyHttpInteraction. |
| * |
| * @param ctx context to receive the response |
| * @param req request to process |
| */ |
| NettyHttpInteraction(ChannelHandlerContext ctx, HttpRequest req) { |
| this.ctx = ctx; |
| this.req = req; |
| } |
| |
| @Override |
| public String getHeader(String header) { |
| return req.headers().get(header); |
| } |
| |
| @Override |
| public String getMethod() { |
| return req.getMethod().name(); |
| } |
| |
| @Override |
| public void proceed() { |
| ReferenceCountUtil.retain(req); |
| ctx.fireChannelRead(req); |
| } |
| |
| @Override |
| public void sendError(int code, String message) { |
| HttpResponseStatus status = new HttpResponseStatus(code, message); |
| sendResponseAndClose(ctx, new DefaultHttpResponse(HTTP_1_1, status)); |
| } |
| } |
| |
| /** |
| * Creates a {@link RestCsrfPreventionFilter} for the {@DatanodeHttpServer}. |
| * This method takes care of configuration and implementing just enough of the |
| * servlet API and related interfaces so that the DataNode can get a fully |
| * initialized instance of the filter. |
| * |
| * @param conf configuration to read |
| * @return initialized filter, or null if CSRF protection not enabled |
| */ |
| public static RestCsrfPreventionFilter initializeState( |
| Configuration conf) { |
| if (!conf.getBoolean(DFS_WEBHDFS_REST_CSRF_ENABLED_KEY, |
| DFS_WEBHDFS_REST_CSRF_ENABLED_DEFAULT)) { |
| return null; |
| } |
| String restCsrfClassName = RestCsrfPreventionFilter.class.getName(); |
| Map<String, String> restCsrfParams = RestCsrfPreventionFilter |
| .getFilterParams(conf, "dfs.webhdfs.rest-csrf."); |
| RestCsrfPreventionFilter filter = new RestCsrfPreventionFilter(); |
| try { |
| filter.init(new DatanodeHttpServer |
| .MapBasedFilterConfig(restCsrfClassName, restCsrfParams)); |
| } catch (ServletException e) { |
| throw new IllegalStateException( |
| "Failed to initialize RestCsrfPreventionFilter.", e); |
| } |
| return(filter); |
| } |
| } |