1*0b57cec5SDimitry Andric //===- FuzzerInterface.h - Interface header for the Fuzzer ------*- C++ -* ===// 2*0b57cec5SDimitry Andric // 3*0b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*0b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 5*0b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*0b57cec5SDimitry Andric // 7*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 8*0b57cec5SDimitry Andric // Define the interface between libFuzzer and the library being tested. 9*0b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 10*0b57cec5SDimitry Andric 11*0b57cec5SDimitry Andric // NOTE: the libFuzzer interface is thin and in the majority of cases 12*0b57cec5SDimitry Andric // you should not include this file into your target. In 95% of cases 13*0b57cec5SDimitry Andric // all you need is to define the following function in your file: 14*0b57cec5SDimitry Andric // extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size); 15*0b57cec5SDimitry Andric 16*0b57cec5SDimitry Andric // WARNING: keep the interface in C. 17*0b57cec5SDimitry Andric 18*0b57cec5SDimitry Andric #ifndef LLVM_FUZZER_INTERFACE_H 19*0b57cec5SDimitry Andric #define LLVM_FUZZER_INTERFACE_H 20*0b57cec5SDimitry Andric 21*0b57cec5SDimitry Andric #include <stddef.h> 22*0b57cec5SDimitry Andric #include <stdint.h> 23*0b57cec5SDimitry Andric 24*0b57cec5SDimitry Andric #ifdef __cplusplus 25*0b57cec5SDimitry Andric extern "C" { 26*0b57cec5SDimitry Andric #endif // __cplusplus 27*0b57cec5SDimitry Andric 28*0b57cec5SDimitry Andric // Define FUZZER_INTERFACE_VISIBILITY to set default visibility in a way that 29*0b57cec5SDimitry Andric // doesn't break MSVC. 30*0b57cec5SDimitry Andric #if defined(_WIN32) 31*0b57cec5SDimitry Andric #define FUZZER_INTERFACE_VISIBILITY __declspec(dllexport) 32*0b57cec5SDimitry Andric #else 33*0b57cec5SDimitry Andric #define FUZZER_INTERFACE_VISIBILITY __attribute__((visibility("default"))) 34*0b57cec5SDimitry Andric #endif 35*0b57cec5SDimitry Andric 36*0b57cec5SDimitry Andric // Mandatory user-provided target function. 37*0b57cec5SDimitry Andric // Executes the code under test with [Data, Data+Size) as the input. 38*0b57cec5SDimitry Andric // libFuzzer will invoke this function *many* times with different inputs. 39*0b57cec5SDimitry Andric // Must return 0. 40*0b57cec5SDimitry Andric FUZZER_INTERFACE_VISIBILITY int 41*0b57cec5SDimitry Andric LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size); 42*0b57cec5SDimitry Andric 43*0b57cec5SDimitry Andric // Optional user-provided initialization function. 44*0b57cec5SDimitry Andric // If provided, this function will be called by libFuzzer once at startup. 45*0b57cec5SDimitry Andric // It may read and modify argc/argv. 46*0b57cec5SDimitry Andric // Must return 0. 47*0b57cec5SDimitry Andric FUZZER_INTERFACE_VISIBILITY int LLVMFuzzerInitialize(int *argc, char ***argv); 48*0b57cec5SDimitry Andric 49*0b57cec5SDimitry Andric // Optional user-provided custom mutator. 50*0b57cec5SDimitry Andric // Mutates raw data in [Data, Data+Size) inplace. 51*0b57cec5SDimitry Andric // Returns the new size, which is not greater than MaxSize. 52*0b57cec5SDimitry Andric // Given the same Seed produces the same mutation. 53*0b57cec5SDimitry Andric FUZZER_INTERFACE_VISIBILITY size_t 54*0b57cec5SDimitry Andric LLVMFuzzerCustomMutator(uint8_t *Data, size_t Size, size_t MaxSize, 55*0b57cec5SDimitry Andric unsigned int Seed); 56*0b57cec5SDimitry Andric 57*0b57cec5SDimitry Andric // Optional user-provided custom cross-over function. 58*0b57cec5SDimitry Andric // Combines pieces of Data1 & Data2 together into Out. 59*0b57cec5SDimitry Andric // Returns the new size, which is not greater than MaxOutSize. 60*0b57cec5SDimitry Andric // Should produce the same mutation given the same Seed. 61*0b57cec5SDimitry Andric FUZZER_INTERFACE_VISIBILITY size_t 62*0b57cec5SDimitry Andric LLVMFuzzerCustomCrossOver(const uint8_t *Data1, size_t Size1, 63*0b57cec5SDimitry Andric const uint8_t *Data2, size_t Size2, uint8_t *Out, 64*0b57cec5SDimitry Andric size_t MaxOutSize, unsigned int Seed); 65*0b57cec5SDimitry Andric 66*0b57cec5SDimitry Andric // Experimental, may go away in future. 67*0b57cec5SDimitry Andric // libFuzzer-provided function to be used inside LLVMFuzzerCustomMutator. 68*0b57cec5SDimitry Andric // Mutates raw data in [Data, Data+Size) inplace. 69*0b57cec5SDimitry Andric // Returns the new size, which is not greater than MaxSize. 70*0b57cec5SDimitry Andric FUZZER_INTERFACE_VISIBILITY size_t 71*0b57cec5SDimitry Andric LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize); 72*0b57cec5SDimitry Andric 73*0b57cec5SDimitry Andric #undef FUZZER_INTERFACE_VISIBILITY 74*0b57cec5SDimitry Andric 75*0b57cec5SDimitry Andric #ifdef __cplusplus 76*0b57cec5SDimitry Andric } // extern "C" 77*0b57cec5SDimitry Andric #endif // __cplusplus 78*0b57cec5SDimitry Andric 79*0b57cec5SDimitry Andric #endif // LLVM_FUZZER_INTERFACE_H 80