--- /dev/null
+/*
+ * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.netconf.nettyutil.handler;
+
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Lists;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufUtil;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.ByteToMessageDecoder;
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+import java.util.List;
+import org.opendaylight.controller.config.util.xml.XmlUtil;
+import org.opendaylight.netconf.api.NetconfDocumentedException;
+import org.opendaylight.netconf.api.NetconfMessage;
+import org.opendaylight.netconf.api.messages.NetconfHelloMessage;
+import org.opendaylight.netconf.api.messages.NetconfHelloMessageAdditionalHeader;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.w3c.dom.Document;
+import org.xml.sax.SAXException;
+
+/**
+ * Customized NetconfXMLToMessageDecoder that reads additional header with
+ * session metadata from
+ * {@link NetconfHelloMessage}*
+ * This handler should be replaced in pipeline by regular message handler as last step of negotiation.
+ * It serves as a message barrier and halts all non-hello netconf messages.
+ * Netconf messages after hello should be processed once the negotiation succeeded.
+ *
+ */
+public final class NetconfXMLToHelloMessageDecoder extends ByteToMessageDecoder {
+ private static final Logger LOG = LoggerFactory.getLogger(NetconfXMLToHelloMessageDecoder.class);
+
+ private static final List<byte[]> POSSIBLE_ENDS = ImmutableList.of(
+ new byte[] { ']', '\n' },
+ new byte[] { ']', '\r', '\n' });
+ private static final List<byte[]> POSSIBLE_STARTS = ImmutableList.of(
+ new byte[] { '[' },
+ new byte[] { '\r', '\n', '[' },
+ new byte[] { '\n', '[' });
+
+ // State variables do not have to by synchronized
+ // Netty uses always the same (1) thread per pipeline
+ // We use instance of this per pipeline
+ private final List<NetconfMessage> nonHelloMessages = Lists.newArrayList();
+ private boolean helloReceived = false;
+
+ @Override
+ @VisibleForTesting
+ public void decode(final ChannelHandlerContext ctx, final ByteBuf in, final List<Object> out)
+ throws IOException, SAXException, NetconfDocumentedException {
+ if (in.readableBytes() == 0) {
+ LOG.debug("No more content in incoming buffer.");
+ return;
+ }
+
+ in.markReaderIndex();
+ try {
+ if (LOG.isTraceEnabled()) {
+ LOG.trace("Received to decode: {}", ByteBufUtil.hexDump(in));
+ }
+
+ byte[] bytes = new byte[in.readableBytes()];
+ in.readBytes(bytes);
+
+ logMessage(bytes);
+
+ // Extract bytes containing header with additional metadata
+ String additionalHeader = null;
+ if (startsWithAdditionalHeader(bytes)) {
+ // Auth information containing username, ip address... extracted for monitoring
+ int endOfAuthHeader = getAdditionalHeaderEndIndex(bytes);
+ if (endOfAuthHeader > -1) {
+ byte[] additionalHeaderBytes = Arrays.copyOfRange(bytes, 0, endOfAuthHeader);
+ additionalHeader = additionalHeaderToString(additionalHeaderBytes);
+ bytes = Arrays.copyOfRange(bytes, endOfAuthHeader, bytes.length);
+ }
+ }
+
+ Document doc = XmlUtil.readXmlToDocument(new ByteArrayInputStream(bytes));
+
+ final NetconfMessage message = getNetconfMessage(additionalHeader, doc);
+ if (message instanceof NetconfHelloMessage) {
+ Preconditions.checkState(helloReceived == false,
+ "Multiple hello messages received, unexpected hello: %s", message);
+ out.add(message);
+ helloReceived = true;
+ // Non hello message, suspend the message and insert into cache
+ } else {
+ Preconditions.checkState(helloReceived, "Hello message not received, instead received: %s", message);
+ LOG.debug("Netconf message received during negotiation, caching {}", message);
+ nonHelloMessages.add(message);
+ }
+ } finally {
+ in.discardReadBytes();
+ }
+ }
+
+ private static NetconfMessage getNetconfMessage(final String additionalHeader, final Document doc)
+ throws NetconfDocumentedException {
+ NetconfMessage msg = new NetconfMessage(doc);
+ if (NetconfHelloMessage.isHelloMessage(msg)) {
+ if (additionalHeader != null) {
+ return new NetconfHelloMessage(doc, NetconfHelloMessageAdditionalHeader.fromString(additionalHeader));
+ } else {
+ return new NetconfHelloMessage(doc);
+ }
+ }
+
+ return msg;
+ }
+
+ private static int getAdditionalHeaderEndIndex(final byte[] bytes) {
+ for (byte[] possibleEnd : POSSIBLE_ENDS) {
+ int idx = findByteSequence(bytes, possibleEnd);
+
+ if (idx != -1) {
+ return idx + possibleEnd.length;
+ }
+ }
+
+ return -1;
+ }
+
+ private static int findByteSequence(final byte[] bytes, final byte[] sequence) {
+ if (bytes.length < sequence.length) {
+ throw new IllegalArgumentException("Sequence to be found is longer than the given byte array.");
+ }
+ if (bytes.length == sequence.length) {
+ if (Arrays.equals(bytes, sequence)) {
+ return 0;
+ } else {
+ return -1;
+ }
+ }
+ int index = 0;
+ for (int i = 0; i < bytes.length; i++) {
+ if (bytes[i] == sequence[index]) {
+ index++;
+ if (index == sequence.length) {
+ return i - index + 1;
+ }
+ } else {
+ index = 0;
+ }
+ }
+ return -1;
+ }
+
+ private static void logMessage(final byte[] bytes) {
+ if (LOG.isDebugEnabled()) {
+ String string = StandardCharsets.UTF_8.decode(ByteBuffer.wrap(bytes)).toString();
+ LOG.debug("Parsing message \n{}", string);
+ }
+ }
+
+ private static boolean startsWithAdditionalHeader(final byte[] bytes) {
+ for (byte[] possibleStart : POSSIBLE_STARTS) {
+ int index = 0;
+ for (byte b : possibleStart) {
+ if (bytes[index++] != b) {
+ break;
+ }
+
+ if (index == possibleStart.length) {
+ return true;
+ }
+ }
+ }
+
+ return false;
+ }
+
+ private static String additionalHeaderToString(final byte[] bytes) {
+ return StandardCharsets.UTF_8.decode(ByteBuffer.wrap(bytes)).toString();
+ }
+
+ /**
+ * Get netconf messages received during negotiation.
+ *
+ * @return Collection of NetconfMessages that were not hello, but were received during negotiation.
+ */
+ public Iterable<NetconfMessage> getPostHelloNetconfMessages() {
+ return nonHelloMessages;
+ }
+}
Code Review / transportpce.git / blobdiff