1 // Copyright 2021 Code Intelligence GmbH 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 package com.example; 16 17 import com.code_intelligence.jazzer.api.FuzzedDataProvider; 18 import com.code_intelligence.jazzer.api.FuzzerSecurityIssueLow; 19 import com.google.gson.Gson; 20 import com.google.gson.JsonElement; 21 import com.google.json.JsonSanitizer; 22 23 public class JsonSanitizerValidJsonFuzzer { fuzzerTestOneInput(FuzzedDataProvider data)24 public static void fuzzerTestOneInput(FuzzedDataProvider data) { 25 String input = data.consumeRemainingAsString(); 26 String validJson; 27 try { 28 validJson = JsonSanitizer.sanitize(input, 10); 29 } catch (Exception e) { 30 return; 31 } 32 33 // Check that the output is valid JSON. Invalid JSON may crash other parts of the application 34 // that trust the output of the sanitizer. 35 try { 36 Gson gson = new Gson(); 37 gson.fromJson(validJson, JsonElement.class); 38 } catch (Exception e) { 39 throw new FuzzerSecurityIssueLow("Output is invalid JSON", e); 40 } 41 } 42 } 43