From 0ba21bef2b7d1fc20befd1497ee5829888ac65de Mon Sep 17 00:00:00 2001
From: Adam Korczynski <adam@adalogics.com>
Date: Sat, 18 Jan 2025 19:23:44 +0000
Subject: [PATCH] Add PatternParser fuzzer

Signed-off-by: Adam Korczynski <adam@adalogics.com>
---
 src/fuzzers/cpp/CMakeLists.txt          |   2 +-
 src/fuzzers/cpp/PatternParserFuzzer.cpp | 129 ++++++++++++++++++++++++
 2 files changed, 130 insertions(+), 1 deletion(-)
 create mode 100644 src/fuzzers/cpp/PatternParserFuzzer.cpp

diff --git a/src/fuzzers/cpp/CMakeLists.txt b/src/fuzzers/cpp/CMakeLists.txt
index 0b7d4f622..7e8da1d1c 100644
--- a/src/fuzzers/cpp/CMakeLists.txt
+++ b/src/fuzzers/cpp/CMakeLists.txt
@@ -15,7 +15,7 @@
 # limitations under the License.
 #
 
-set(ALL_LOG4CXX_FUZZERS PatternLayoutFuzzer XMLLayoutFuzzer)
+set(ALL_LOG4CXX_FUZZERS PatternLayoutFuzzer XMLLayoutFuzzer PatternParserFuzzer)
 set(LOG4CXX_CHAR "utf-8")
 
 # Get the most recent Git commit ID
diff --git a/src/fuzzers/cpp/PatternParserFuzzer.cpp b/src/fuzzers/cpp/PatternParserFuzzer.cpp
new file mode 100644
index 000000000..081e3b7ff
--- /dev/null
+++ b/src/fuzzers/cpp/PatternParserFuzzer.cpp
@@ -0,0 +1,129 @@
+/*
+ * 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.
+ */
+
+#include "stdint.h"
+#include <log4cxx/nt/nteventlogappender.h>
+#include <log4cxx/logstring.h>
+#include <log4cxx/helpers/stringhelper.h>
+#include <fuzzer/FuzzedDataProvider.h>
+#include <log4cxx/pattern/patternparser.h>
+
+#include <log4cxx/pattern/loggerpatternconverter.h>
+#include <log4cxx/pattern/literalpatternconverter.h>
+#include <log4cxx/pattern/classnamepatternconverter.h>
+#include <log4cxx/pattern/datepatternconverter.h>
+#include <log4cxx/pattern/filedatepatternconverter.h>
+#include <log4cxx/pattern/filelocationpatternconverter.h>
+#include <log4cxx/pattern/fulllocationpatternconverter.h>
+#include <log4cxx/pattern/integerpatternconverter.h>
+#include <log4cxx/pattern/linelocationpatternconverter.h>
+#include <log4cxx/pattern/messagepatternconverter.h>
+#include <log4cxx/pattern/lineseparatorpatternconverter.h>
+#include <log4cxx/pattern/methodlocationpatternconverter.h>
+#include <log4cxx/pattern/levelpatternconverter.h>
+#include <log4cxx/pattern/relativetimepatternconverter.h>
+#include <log4cxx/pattern/threadpatternconverter.h>
+#include <log4cxx/pattern/ndcpatternconverter.h>
+#include <log4cxx/pattern/propertiespatternconverter.h>
+#include <log4cxx/pattern/throwableinformationpatternconverter.h>
+#include <log4cxx/pattern/threadusernamepatternconverter.h>
+
+using namespace log4cxx;
+using namespace log4cxx::helpers;
+using namespace log4cxx::spi;
+using namespace log4cxx::pattern;
+
+#define RULES_PUT(spec, cls) \
+	map.insert(PatternMap::value_type(LOG4CXX_STR(spec), (PatternConstructor) cls ::newInstance))
+
+PatternMap getFormatSpecifiers()
+{
+	PatternMap map;
+	RULES_PUT("c", LoggerPatternConverter);
+	RULES_PUT("logger", LoggerPatternConverter);
+
+	RULES_PUT("C", ClassNamePatternConverter);
+	RULES_PUT("class", ClassNamePatternConverter);
+
+	RULES_PUT("d", DatePatternConverter);
+	RULES_PUT("date", DatePatternConverter);
+
+	RULES_PUT("F", FileLocationPatternConverter);
+	RULES_PUT("file", FileLocationPatternConverter);
+
+	RULES_PUT("l", FullLocationPatternConverter);
+
+	RULES_PUT("L", LineLocationPatternConverter);
+	RULES_PUT("line", LineLocationPatternConverter);
+
+	RULES_PUT("m", MessagePatternConverter);
+	RULES_PUT("message", MessagePatternConverter);
+
+	RULES_PUT("n", LineSeparatorPatternConverter);
+
+	RULES_PUT("M", MethodLocationPatternConverter);
+	RULES_PUT("method", MethodLocationPatternConverter);
+
+	RULES_PUT("p", LevelPatternConverter);
+	RULES_PUT("level", LevelPatternConverter);
+
+	RULES_PUT("r", RelativeTimePatternConverter);
+	RULES_PUT("relative", RelativeTimePatternConverter);
+
+	RULES_PUT("t", ThreadPatternConverter);
+	RULES_PUT("thread", ThreadPatternConverter);
+
+	RULES_PUT("T", ThreadUsernamePatternConverter);
+	RULES_PUT("threadname", ThreadUsernamePatternConverter);
+
+	RULES_PUT("x", NDCPatternConverter);
+	RULES_PUT("ndc", NDCPatternConverter);
+
+	RULES_PUT("X", PropertiesPatternConverter);
+	RULES_PUT("properties", PropertiesPatternConverter);
+
+	RULES_PUT("throwable", ThrowableInformationPatternConverter);
+
+	return map;
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+	// Create a FuzzedDataProvider which we
+	// will use to create strings from "data".
+	FuzzedDataProvider fdp(data, size);
+	
+	std::string loggerStr = fdp.ConsumeRandomLengthString();
+	std::string content = fdp.ConsumeRandomLengthString();
+
+	// Create the event
+	log4cxx::LogString logger = LOG4CXX_STR(loggerStr);
+	log4cxx::LevelPtr level = log4cxx::Level::getInfo();
+	log4cxx::spi::LoggingEventPtr event = log4cxx::spi::LoggingEventPtr(
+		new log4cxx::spi::LoggingEvent(
+			logger, level, LOG4CXX_STR(content), LOG4CXX_LOCATION));
+
+
+	log4cxx::helpers::Pool p;
+	PatternMap patternMap = getFormatSpecifiers();
+	std::vector<PatternConverterPtr> converters;
+	std::vector<FormattingInfoPtr> fields;
+
+	log4cxx::LogString pattern = LOG4CXX_STR(fdp.ConsumeRandomLengthString());
+	PatternParser::parse(pattern, converters, fields, patternMap);
+
+  	return 0;
+}