1*3cab2bb3Spatrick //===- FuzzerInterface.h - Interface header for the Fuzzer ------*- C++ -* ===// 2*3cab2bb3Spatrick // 3*3cab2bb3Spatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*3cab2bb3Spatrick // See https://llvm.org/LICENSE.txt for license information. 5*3cab2bb3Spatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*3cab2bb3Spatrick // 7*3cab2bb3Spatrick //===----------------------------------------------------------------------===// 8*3cab2bb3Spatrick // Define the interface between libFuzzer and the library being tested. 9*3cab2bb3Spatrick //===----------------------------------------------------------------------===// 10*3cab2bb3Spatrick 11*3cab2bb3Spatrick // NOTE: the libFuzzer interface is thin and in the majority of cases 12*3cab2bb3Spatrick // you should not include this file into your target. In 95% of cases 13*3cab2bb3Spatrick // all you need is to define the following function in your file: 14*3cab2bb3Spatrick // extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size); 15*3cab2bb3Spatrick 16*3cab2bb3Spatrick // WARNING: keep the interface in C. 17*3cab2bb3Spatrick 18*3cab2bb3Spatrick #ifndef LLVM_FUZZER_INTERFACE_H 19*3cab2bb3Spatrick #define LLVM_FUZZER_INTERFACE_H 20*3cab2bb3Spatrick 21*3cab2bb3Spatrick #include <stddef.h> 22*3cab2bb3Spatrick #include <stdint.h> 23*3cab2bb3Spatrick 24*3cab2bb3Spatrick #ifdef __cplusplus 25*3cab2bb3Spatrick extern "C" { 26*3cab2bb3Spatrick #endif // __cplusplus 27*3cab2bb3Spatrick 28*3cab2bb3Spatrick // Define FUZZER_INTERFACE_VISIBILITY to set default visibility in a way that 29*3cab2bb3Spatrick // doesn't break MSVC. 30*3cab2bb3Spatrick #if defined(_WIN32) 31*3cab2bb3Spatrick #define FUZZER_INTERFACE_VISIBILITY __declspec(dllexport) 32*3cab2bb3Spatrick #else 33*3cab2bb3Spatrick #define FUZZER_INTERFACE_VISIBILITY __attribute__((visibility("default"))) 34*3cab2bb3Spatrick #endif 35*3cab2bb3Spatrick 36*3cab2bb3Spatrick // Mandatory user-provided target function. 37*3cab2bb3Spatrick // Executes the code under test with [Data, Data+Size) as the input. 38*3cab2bb3Spatrick // libFuzzer will invoke this function *many* times with different inputs. 39*3cab2bb3Spatrick // Must return 0. 40*3cab2bb3Spatrick FUZZER_INTERFACE_VISIBILITY int 41*3cab2bb3Spatrick LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size); 42*3cab2bb3Spatrick 43*3cab2bb3Spatrick // Optional user-provided initialization function. 44*3cab2bb3Spatrick // If provided, this function will be called by libFuzzer once at startup. 45*3cab2bb3Spatrick // It may read and modify argc/argv. 46*3cab2bb3Spatrick // Must return 0. 47*3cab2bb3Spatrick FUZZER_INTERFACE_VISIBILITY int LLVMFuzzerInitialize(int *argc, char ***argv); 48*3cab2bb3Spatrick 49*3cab2bb3Spatrick // Optional user-provided custom mutator. 50*3cab2bb3Spatrick // Mutates raw data in [Data, Data+Size) inplace. 51*3cab2bb3Spatrick // Returns the new size, which is not greater than MaxSize. 52*3cab2bb3Spatrick // Given the same Seed produces the same mutation. 53*3cab2bb3Spatrick FUZZER_INTERFACE_VISIBILITY size_t 54*3cab2bb3Spatrick LLVMFuzzerCustomMutator(uint8_t *Data, size_t Size, size_t MaxSize, 55*3cab2bb3Spatrick unsigned int Seed); 56*3cab2bb3Spatrick 57*3cab2bb3Spatrick // Optional user-provided custom cross-over function. 58*3cab2bb3Spatrick // Combines pieces of Data1 & Data2 together into Out. 59*3cab2bb3Spatrick // Returns the new size, which is not greater than MaxOutSize. 60*3cab2bb3Spatrick // Should produce the same mutation given the same Seed. 61*3cab2bb3Spatrick FUZZER_INTERFACE_VISIBILITY size_t 62*3cab2bb3Spatrick LLVMFuzzerCustomCrossOver(const uint8_t *Data1, size_t Size1, 63*3cab2bb3Spatrick const uint8_t *Data2, size_t Size2, uint8_t *Out, 64*3cab2bb3Spatrick size_t MaxOutSize, unsigned int Seed); 65*3cab2bb3Spatrick 66*3cab2bb3Spatrick // Experimental, may go away in future. 67*3cab2bb3Spatrick // libFuzzer-provided function to be used inside LLVMFuzzerCustomMutator. 68*3cab2bb3Spatrick // Mutates raw data in [Data, Data+Size) inplace. 69*3cab2bb3Spatrick // Returns the new size, which is not greater than MaxSize. 70*3cab2bb3Spatrick FUZZER_INTERFACE_VISIBILITY size_t 71*3cab2bb3Spatrick LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize); 72*3cab2bb3Spatrick 73*3cab2bb3Spatrick #undef FUZZER_INTERFACE_VISIBILITY 74*3cab2bb3Spatrick 75*3cab2bb3Spatrick #ifdef __cplusplus 76*3cab2bb3Spatrick } // extern "C" 77*3cab2bb3Spatrick #endif // __cplusplus 78*3cab2bb3Spatrick 79*3cab2bb3Spatrick #endif // LLVM_FUZZER_INTERFACE_H 80