[Oss-Fuzz] Adding fuzzer-stl_operations

Makefile

@@ -44,6 +44,7 @@ all:
 	@echo "fuzz_testing_cbor - prepare fuzz testing of the CBOR parser"
 	@echo "fuzz_testing_msgpack - prepare fuzz testing of the MessagePack parser"
 	@echo "fuzz_testing_ubjson - prepare fuzz testing of the UBJSON parser"
+	@echo "fuzz_testing_stl - prepare fuzz testing of STL operators"
 	@echo "json_unit - create single-file test executable"
 	@echo "pedantic_clang - run Clang with maximal warning flags"
 	@echo "pedantic_gcc - run GCC with maximal warning flags"
@@ -402,6 +403,14 @@ fuzz_testing_ubjson:
 	find test/data -size -5k -name *.ubjson | xargs -I{} cp "{}" fuzz-testing/testcases
 	@echo "Execute: afl-fuzz -i fuzz-testing/testcases -o fuzz-testing/out fuzz-testing/fuzzer"
 
+fuzz_testing_stl:
+	rm -fr fuzz-testing
+	mkdir -p fuzz-testing fuzz-testing/testcases fuzz-testing/out
+	$(MAKE) stl_operations_fuzzer -C test CXX=afl-clang++
+	mv test/stl_operations_fuzzer fuzz-testing/fuzzer
+	find test/data -size -5k -name *.json | xargs -I{} cp "{}" fuzz-testing/testcases
+	@echo "Execute: afl-fuzz -i fuzz-testing/testcases -o fuzz-testing/out fuzz-testing/fuzzer"
+
 fuzzing-start:
 	afl-fuzz -S fuzzer1 -i fuzz-testing/testcases -o fuzz-testing/out fuzz-testing/fuzzer > /dev/null &
 	afl-fuzz -S fuzzer2 -i fuzz-testing/testcases -o fuzz-testing/out fuzz-testing/fuzzer > /dev/null &

test/Makefile

@@ -94,7 +94,7 @@ check: $(OBJECTS) $(TESTCASES)
 ##############################################################################
 
 FUZZER_ENGINE = src/fuzzer-driver_afl.cpp
-FUZZERS = parse_afl_fuzzer parse_bson_fuzzer parse_cbor_fuzzer parse_msgpack_fuzzer parse_ubjson_fuzzer
+FUZZERS = parse_afl_fuzzer parse_bson_fuzzer parse_cbor_fuzzer parse_msgpack_fuzzer parse_ubjson_fuzzer stl_operations_fuzzer
 fuzzers: $(FUZZERS)
 
 parse_afl_fuzzer:
@@ -111,3 +111,6 @@ parse_msgpack_fuzzer:
 
 parse_ubjson_fuzzer:
 	$(CXX) $(CXXFLAGS) $(CPPFLAGS) $(FUZZER_ENGINE) src/fuzzer-parse_ubjson.cpp -o $@
+
+stl_operations_fuzzer:
+	$(CXX) $(CXXFLAGS) $(CPPFLAGS) $(FUZZER_ENGINE) src/fuzzer-stl_operations.cpp -o $@

test/src/fuzzer-stl_operations.cpp

@@ -0,0 +1,140 @@
+/*
+    __ _____ _____ _____
+ __|  |   __|     |   | |  JSON for Modern C++ (fuzz test support)
+|  |  |__   |  |  | | | |  version 3.7.3
+|_____|_____|_____|_|___|  https://github.com/nlohmann/json
+
+This file implements test for stl operations suitable for fuzz testing.
+
+The provided function `LLVMFuzzerTestOneInput` can be used in different fuzzer
+drivers.
+
+Licensed under the MIT License <http://opensource.org/licenses/MIT>.
+*/
+
+#include <iostream>
+#include <deque>
+#include <list>
+#include <set>
+#include <unordered_set>
+#include <iterator> 
+#include <map>
+#include <unordered_map>
+#include <utility>
+#include <sstream>
+#include <nlohmann/json.hpp>
+
+using json = nlohmann::json;
+
+// see http://llvm.org/docs/LibFuzzer.html
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size)
+{
+    // putting data in several STL containers
+    std::vector<uint8_t> vec(data, data + size);
+    std::deque<uint8_t> deq(data, data + size);
+    std::list<uint8_t> lst(data, data + size);
+    std::forward_list<uint8_t> flist(data, data + size);
+    std::set<uint8_t> st(data, data + size);
+    std::unordered_set<uint8_t> uset(data, data + size);
+    std::multiset<uint8_t> multist(data, data + size);
+    std::unordered_multiset<uint8_t> umultiset(data, data + size);
+
+    // parsing from STL containers
+    json j_vector(vec);
+    json j_deque(deq);
+    json j_list(lst);
+    json j_flist(flist);
+    json j_set(st);
+    json j_uset(uset);
+    json j_multiset(multist);
+    json j_umultiset(umultiset);
+
+    // json must be same for sequence containers
+    assert(j_vector == j_deque);
+    assert(j_vector == j_list);
+    assert(j_vector == j_flist);
+
+    // iterating json array and testing get() method
+    for(json::iterator it = j_vector.begin(); it != j_vector.end(); ++it)
+    {
+        try
+        {
+            int temp = (*it).get<int>();
+        }
+        catch(const json::type_error)
+        {
+            // input might not be convertible to integer
+        }
+    }
+
+    for(auto& element : j_vector)
+    {
+        // range-based iteration
+    }
+
+    json j_vector2 = json::array();
+    json j_vector3 = json::array();
+
+    for(std::size_t i = 0; i < j_vector.size(); ++i)
+    {
+        auto temp = j_vector.at(i);
+        // testing at() method
+        j_vector2.push_back(temp);
+        j_vector3.emplace_back(temp);
+        // testing push_back and emplace back methods
+    }
+
+    // these three json vectors must be the same
+    assert(j_vector == j_vector2);
+    assert(j_vector == j_vector3);
+
+    std::map<std::string, uint8_t> mp;
+    std::unordered_map<std::string, uint8_t> umap;
+    std::multimap<std::string, uint8_t> multimp;
+    std::unordered_multimap<std::string, uint8_t> umultimap;
+
+    // converting each consecutive entry in the vector into a key-value pair and adding them to map
+    for(std::size_t i = 1; i < vec.size(); i+=2)
+    {
+    	int last_entry = static_cast<int>(vec[i-1]);
+    	std::string key_str = std::to_string(last_entry);
+        std::pair<std::string, uint8_t> insert_data = std::make_pair(key_str, vec[i]);
+        mp.insert(insert_data);
+        umap.insert(insert_data);
+        multimp.insert(insert_data);
+        umultimap.insert(insert_data);
+    }
+
+    // map -> json map
+    json j_map(mp);
+    json j_umap(umap);
+    json j_multimap(multimp);
+    json j_umultimap(umultimap);
+
+    // iterating json map
+    for(json::iterator it = j_map.begin(); it != j_map.end(); ++it)
+    {
+        auto temp1 = it.key();
+        auto temp2 = it.value();
+    }
+
+    try
+    {
+        // parse input directly
+        json j1 = json::parse(data, data + size);
+        // parse using vector
+        json j_vec = json::parse(vec);
+
+        // both of them must be equal
+        assert(j1 == j_vec);
+    }
+    catch (const json::parse_error&)
+    {
+        // parse errors are ok, because input may be random bytes
+    }
+    catch (const json::out_of_range&)
+    {
+        // out of range errors may happen if provided sizes are excessive
+    }
+    return 0;
+}