JackHintonSmartDCSIT commented on code in PR #8691: URL: https://github.com/apache/nifi/pull/8691#discussion_r1643247704
########## nifi-extension-bundles/nifi-network-bundle/nifi-network-processors/src/main/java/org/apache/nifi/processors/network/pcap/SplitPCAP.java: ########## @@ -0,0 +1,237 @@ +/* + * 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.nifi.processors.network.pcap; + +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.flowfile.FlowFile; +import org.apache.nifi.annotation.behavior.InputRequirement; +import org.apache.nifi.annotation.behavior.InputRequirement.Requirement; +import org.apache.nifi.annotation.behavior.SideEffectFree; +import org.apache.nifi.annotation.behavior.WritesAttribute; +import org.apache.nifi.annotation.behavior.WritesAttributes; +import org.apache.nifi.annotation.documentation.CapabilityDescription; +import org.apache.nifi.annotation.documentation.Tags; +import org.apache.nifi.processor.AbstractProcessor; +import org.apache.nifi.processor.DataUnit; +import org.apache.nifi.processor.ProcessContext; +import org.apache.nifi.processor.ProcessSession; +import org.apache.nifi.processor.Relationship; +import org.apache.nifi.processor.exception.ProcessException; +import org.apache.nifi.processor.util.StandardValidators; +import org.apache.nifi.flowfile.attributes.FragmentAttributes; +import org.apache.nifi.flowfile.attributes.CoreAttributes; +import org.apache.nifi.processor.io.InputStreamCallback; + +import java.io.BufferedInputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.OutputStream; +import java.util.ArrayList; +import java.util.List; +import java.util.Set; +import java.util.UUID; +import java.util.HashMap; +import java.util.Map; +import java.util.stream.IntStream; + +@SideEffectFree +@InputRequirement(Requirement.INPUT_REQUIRED) +@Tags({"PCAP", "Splitter", "Network", "Packet", "Capture", "Wireshark", "TShark", "TcpDump", "WinDump", "sniffers"}) +@CapabilityDescription("Splits a pcap file into multiple pcap files based on a maximum size.") +@WritesAttributes({ + @WritesAttribute( + attribute = SplitPCAP.ERROR_REASON_LABEL, + description = "The reason the flowfile was sent to the failure relationship." + ), + @WritesAttribute( + attribute = "fragment.identifier", + description = "All split PCAP FlowFiles produced from the same parent PCAP FlowFile will have the same randomly generated UUID added for this attribute" + ), + @WritesAttribute( + attribute = "fragment.index", + description = "A one-up number that indicates the ordering of the split PCAP FlowFiles that were created from a single parent PCAP FlowFile" + ), + @WritesAttribute( + attribute = "fragment.count", + description = "The number of split PCAP FlowFiles generated from the parent PCAP FlowFile" + ), + @WritesAttribute( + attribute = "segment.original.filename ", + description = "The filename of the parent PCAP FlowFile" + ) +}) + +public class SplitPCAP extends AbstractProcessor { + + protected static final String ERROR_REASON_LABEL = "ERROR_REASON"; + public static final String FRAGMENT_ID = FragmentAttributes.FRAGMENT_ID.key(); + public static final String FRAGMENT_INDEX = FragmentAttributes.FRAGMENT_INDEX.key(); + public static final String FRAGMENT_COUNT = FragmentAttributes.FRAGMENT_COUNT.key(); + public static final String SEGMENT_ORIGINAL_FILENAME = FragmentAttributes.SEGMENT_ORIGINAL_FILENAME.key(); + + public static final PropertyDescriptor PCAP_MAX_SIZE = new PropertyDescriptor + .Builder().name("PCAP Max Size") + .displayName("PCAP Max Size") + .description("Maximum size of the output pcap file in bytes. Defaults to 1MB (1000000)") + .required(true) + .defaultValue("1MB") + .addValidator(StandardValidators.DATA_SIZE_VALIDATOR) + .build(); + + public static final Relationship REL_ORIGINAL = new Relationship.Builder() + .name("original") + .description("The original FlowFile that was split into segments. If the FlowFile fails processing, nothing will be sent to " + + "this relationship") + .build(); + public static final Relationship REL_FAILURE = new Relationship.Builder() + .name("failure") + .description("If a FlowFile cannot be transformed from the configured input format to the configured output format, " + + "the unchanged FlowFile will be routed to this relationship.") + .build(); + public static final Relationship REL_SPLIT = new Relationship.Builder() + .name("split") + .description("The individual PCAP 'segments' of the original PCAP FlowFile will be routed to this relationship.") + .build(); + + private static final List<PropertyDescriptor> DESCRIPTORS = List.of(PCAP_MAX_SIZE); + private static final Set<Relationship> RELATIONSHIPS = Set.of(REL_ORIGINAL, REL_FAILURE, REL_SPLIT); + + @Override + public Set<Relationship> getRelationships() { + return RELATIONSHIPS; + } + + @Override + public final List<PropertyDescriptor> getSupportedPropertyDescriptors() { + return DESCRIPTORS; + } + + /** + * This method is called when a trigger event occurs in the processor. + * It processes the incoming flow file, splits it into smaller pcap files based on the PCAP Max Size, + * and transfers the split pcap files to the success relationship. + * If the flow file is empty or not parseable, it is transferred to the failure relationship. + * + * @param context the process context + * @param session the process session + */ + @Override + public void onTrigger(final ProcessContext context, final ProcessSession session) { + + FlowFile flowFile = session.get(); + if (flowFile == null) { + return; + } + + final List<FlowFile> splitFiles = new ArrayList<>(); + + try { + session.read(flowFile, new InputStreamCallback() { + @Override + public void process(final InputStream inStream) throws IOException { + final int pcapMaxSize = context.getProperty(PCAP_MAX_SIZE.getName()).asDataSize(DataUnit.B).intValue(); + final List<Packet> loadedPackets = new ArrayList<>(); + final BufferedInputStream bInStream = new BufferedInputStream(inStream); + int totalPackets = 0; + + if ( bInStream.available() == 0 ) { + throw new ProcessException("PCAP file empty."); + } + + final byte[] pcapHeader = new byte[PCAP.PCAP_HEADER_LENGTH]; + bInStream.read(pcapHeader, 0, PCAP.PCAP_HEADER_LENGTH); + int currentPcapTotalLength = PCAP.PCAP_HEADER_LENGTH; + + final PCAP templatePcap = new PCAP(new ByteBufferInterface(pcapHeader)); + + while (bInStream.available() > 0) { + + byte[] packetHeader = new byte[Packet.PACKET_HEADER_LENGTH]; + bInStream.read(packetHeader, 0, Packet.PACKET_HEADER_LENGTH); + Packet currentPacket = new Packet(packetHeader, templatePcap); + + if (currentPacket.totalLength() > pcapMaxSize) { + throw new ProcessException("PCAP contains a packet larger than the max size."); + } + + byte[] packetbody = new byte[(int) currentPacket.expectedLength()]; + + bInStream.read(packetbody, 0, (int) currentPacket.expectedLength()); + currentPacket.setBody(packetbody); + + if (currentPacket.isInvalid()) { + throw new ProcessException("PCAP contains an invalid packet. Packet number " + totalPackets + 1 + " is invalid - " + currentPacket.invalidityReason()); + } + + if (currentPcapTotalLength + currentPacket.totalLength() > pcapMaxSize) { + + templatePcap.packets().addAll(loadedPackets); + FlowFile newFlowFile = session.create(flowFile); + try (final OutputStream out = session.write(newFlowFile)) { + out.write(templatePcap.readBytesFull()); + splitFiles.add(newFlowFile); + } + + loadedPackets.clear(); + currentPcapTotalLength = PCAP.PCAP_HEADER_LENGTH; + templatePcap.packets().clear(); + } + + loadedPackets.add(currentPacket); + totalPackets++; + currentPcapTotalLength += currentPacket.totalLength(); + } + + // If there are any packets left over, create a new flowfile. + if (!loadedPackets.isEmpty()) { + templatePcap.packets().addAll(loadedPackets); + FlowFile newFlowFile = session.create(flowFile); + try (final OutputStream out = session.write(newFlowFile)) { + out.write(templatePcap.readBytesFull()); + splitFiles.add(newFlowFile); + } + } + } + }); + } catch (ProcessException e) { + getLogger().error("Failed to split {}", flowFile, e); + session.remove(splitFiles); + splitFiles.clear(); + session.putAttribute(flowFile, ERROR_REASON_LABEL, e.getMessage()); + session.transfer(flowFile, REL_FAILURE); + return; + } + + final String fragmentId = UUID.randomUUID().toString(); + final String originalFileName = flowFile.getAttribute(CoreAttributes.FILENAME.key()); + final String originalFileNameWithoutExtension = originalFileName.substring(0, originalFileName.lastIndexOf(".")); + + final Map<String, String> attributes = new HashMap<>(); + attributes.put(FRAGMENT_COUNT, String.valueOf(splitFiles.size())); + attributes.put(FRAGMENT_ID, fragmentId); + attributes.put(SEGMENT_ORIGINAL_FILENAME, originalFileName); + + IntStream.range(0, splitFiles.size()).forEach(index -> { + FlowFile split = splitFiles.get(index); + attributes.put(CoreAttributes.FILENAME.key(), originalFileNameWithoutExtension + "-" + index + ".pcap"); + attributes.put(FRAGMENT_INDEX, Integer.toString(index)); + session.putAllAttributes(split, attributes); Review Comment: I'm not sure what you mean with regards to the reference used here, does that mean I should put the call session.transfer inside this loop and call it per 'split' instead of calling it once with 'splitFiles'? The attributes are all set at the end rather than in the processing loop because it was mentioned that it's a bad idea to call session.putAttribute too many times (link [here](https://github.com/apache/nifi/pull/8691#discussion_r1605163620) and the value for the 'FRAGMENT_COUNT' attribute can only be determined after the main loop completes. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
