simonellistonball commented on a change in pull request #1408: METRON-2118: Added a LEEF parser URL: https://github.com/apache/metron/pull/1408#discussion_r285262583
########## File path: metron-platform/metron-parsing/metron-parsers/src/main/java/org/apache/metron/parsers/leef/LEEFParser.java ########## @@ -0,0 +1,236 @@ +/** + * 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.metron.parsers.leef; + +import java.lang.invoke.MethodHandles; +import java.nio.charset.Charset; +import java.text.SimpleDateFormat; +import java.time.Clock; +import java.util.ArrayList; +import java.util.List; +import java.util.Map; +import java.util.regex.Matcher; +import java.util.regex.Pattern; + +import org.apache.metron.parsers.BasicParser; +import org.apache.metron.parsers.ParseException; +import org.apache.metron.parsers.cef.CEFParser; +import org.apache.metron.parsers.utils.DateUtils; +import org.apache.metron.parsers.utils.SyslogUtils; +import org.json.simple.JSONObject; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class LEEFParser extends BasicParser { + private static final long serialVersionUID = 1L; + + protected static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass()); + private static final String HEADER_CAPTURE_PATTERN = "[^\\|]*"; + private static final Charset UTF_8 = Charset.forName("UTF-8"); + private static final String EXTENSION_CAPTURE_PATTERN = "(?<!\\\\)="; + + private Pattern p; + private Pattern pext; + + public void init() { + + // CEF Headers: Device Vendor|Device Product|Device Version|Device Event + // Class ID|Name|Severity + + String syslogTime = "(?:Jan(?:uary)?|Feb(?:ruary)?|Mar(?:ch)?|Apr(?:il)?|May|Jun(?:e)?|Jul(?:y)?|Aug(?:ust)?|Sep(?:tember)?|Oct(?:ober)?|Nov(?:ember)?|Dec(?:ember)?)\\b +(?:(?:0[1-9])|(?:[12][0-9])|(?:3[01])|[1-9]) (?!<[0-9])(?:2[0123]|[01]?[0-9]):(?:[0-5][0-9])(?::(?:(?:[0-5]?[0-9]|60)(?:[:.,][0-9]+)?))(?![0-9])?"; + String syslogTime5424 = "(?:\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}(?:\\.\\d+)?(?:Z|[+-]\\d{2}:\\d{2}))"; + String syslogPriority = "<(?:[0-9]+)>"; + String syslogHost = "[a-z0-9\\.\\\\-_]+"; + + StringBuilder sb = new StringBuilder(""); + sb.append("(?<syslogPriority>"); + sb.append(syslogPriority); + sb.append(")?"); + sb.append("(?<syslogTime>"); + sb.append(syslogTime); + sb.append("|"); + sb.append(syslogTime5424); + sb.append(")?"); + + sb.append("(?<syslogHost>"); + sb.append(syslogHost); + sb.append(")?"); + + sb.append(".*"); + + sb.append("LEEF:(?<Version>1.0|2.0|0)?\\|"); + + headerBlock("DeviceVendor", sb); + sb.append("\\|"); + headerBlock("DeviceProduct", sb); + sb.append("\\|"); + headerBlock("DeviceVersion", sb); + sb.append("\\|"); + headerBlock("DeviceEvent", sb); + sb.append("\\|"); + + // add optional delimiter header (only applicable for LEEF 2.0) + sb.append("("); + headerBlock("Delimiter", sb); + sb.append("\\|"); + sb.append(")?"); + + // extension capture: + sb.append(" ?(?<extensions>.*)"); + String pattern = sb.toString(); + + p = Pattern.compile(pattern); + + pext = Pattern.compile(EXTENSION_CAPTURE_PATTERN); + } + + @SuppressWarnings("unchecked") + public List<JSONObject> parse(byte[] rawMessage) { + List<JSONObject> messages = new ArrayList<>(); + + String cefString = new String(rawMessage, UTF_8); + + Matcher matcher = p.matcher(cefString); + + while (matcher.find()) { + JSONObject obj = new JSONObject(); + if (!matcher.matches()) { + break; + } + LOG.debug("Found %d groups", matcher.groupCount()); + obj.put("DeviceVendor", matcher.group("DeviceVendor")); + obj.put("DeviceProduct", matcher.group("DeviceProduct")); + obj.put("DeviceVersion", matcher.group("DeviceVersion")); + obj.put("DeviceEvent", matcher.group("DeviceEvent")); + + String ext = matcher.group("extensions"); + + // In LEEF 2.0 the delimiter can be specified + String version = matcher.group("Version"); + if (version.equals("2.0")) { + String delimiter = matcher.group("Delimiter"); + if (delimiter == null || delimiter.length() == 0) { + delimiter = "\\t"; + } + delimiter = "(?<!\\\\)[" + delimiter.replace("^", "\\^").replace("\t", "\\t") + "]"; + + String[] kvs = ext.split(delimiter); + for (String kv: kvs) { + String[] a = kv.split("="); + obj.put(a[0], a[1]); + } + } else if (version.equals("1.0") || version.isEmpty()) { + // TODO - Support LEEF 1.0 delimiters + String delimiter = "\t"; + String[] kvs = ext.split(delimiter); + for (String kv: kvs) { + String[] a = kv.split("="); + obj.put(a[0], a[1]); + } + } else { + // Found in the wild examples using CEF rules, which need to handle the processing per the CEFParser + // Note that technically LEEF does not support the CEF approach to numbered custom variables. + // We however do here, due to some found in the wild exceptions to the standard. + CEFParser.parseExtensions(ext, obj); + } + + // Rename standard CEF fields to comply with Metron standards + obj = mutate(obj, "dst", "ip_dst_addr"); + obj = mutate(obj, "dstPort", "ip_dst_port"); + obj = convertToInt(obj, "ip_dst_port"); + + obj = mutate(obj, "src", "ip_src_addr"); + obj = mutate(obj, "srcPort", "ip_src_port"); + obj = convertToInt(obj, "ip_src_port"); + + obj.put("original_string", cefString); + + // apply timestamp from message if present, using devTime, syslog + // timestamp, + // default to current system time + //devTime, devTimeFormat, calLanguage, calCountryOrRegion + if (obj.containsKey("devTime")) { + String devTime = (String) obj.get("devTime"); + try { + // DateFormats allowed in LEEF + // epoch + // MMM dd yyyy HH:mm:ss + // MMM dd yyyy HH:mm:ss.SSS + // MMM dd yyyy HH:mm:ss.SSS zzz + // custom in devTimeFormat field + final String devTimeFormat = (String) obj.get("devTimeFormat"); + + List<SimpleDateFormat> formats = (obj.containsKey("devTimeFormat"))? + new ArrayList<SimpleDateFormat>() {{ add(new SimpleDateFormat(devTimeFormat)); }}: + DateUtils.DATE_FORMATS_LEEF; + obj.put("timestamp", DateUtils.parseMultiformat(devTime, formats )); + } catch (java.text.ParseException e) { + throw new IllegalStateException("devTime field present in LEEF but cannot be parsed", e); + } + } else { + String logTimestamp = matcher.group("syslogTime"); + if (!(logTimestamp == null || logTimestamp.isEmpty())) { + try { + obj.put("timestamp", SyslogUtils.parseTimestampToEpochMillis(logTimestamp, Clock.systemUTC())); + } catch (ParseException e) { + throw new IllegalStateException("Cannot parse syslog timestamp", e); + } + } else { + obj.put("timestamp", System.currentTimeMillis()); + } + } + + // add the host + String host = matcher.group("syslogHost"); + if (!(host == null || host.isEmpty())) { + obj.put("host", host); + } + + messages.add(obj); + } + return messages; + } + + @SuppressWarnings("unchecked") + private JSONObject convertToInt(JSONObject obj, String key) { + if (obj.containsKey(key)) { + obj.put(key, Integer.valueOf((String) obj.get(key))); + } + return obj; + } + + private void headerBlock(String name, StringBuilder sb) { + sb.append("(?<").append(name).append(">").append(HEADER_CAPTURE_PATTERN).append(")"); + } + + @Override + public void configure(Map<String, Object> config) { + // TODO Auto-generated method stub Review comment: done ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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