diff options
Diffstat (limited to 'examples/aflpp_driver/aflpp_driver.cpp')
-rw-r--r-- | examples/aflpp_driver/aflpp_driver.cpp | 292 |
1 files changed, 0 insertions, 292 deletions
diff --git a/examples/aflpp_driver/aflpp_driver.cpp b/examples/aflpp_driver/aflpp_driver.cpp deleted file mode 100644 index d6163bdf..00000000 --- a/examples/aflpp_driver/aflpp_driver.cpp +++ /dev/null @@ -1,292 +0,0 @@ -//===- afl_driver.cpp - a glue between AFL and libFuzzer --------*- C++ -* ===// -// -// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. -// See https://llvm.org/LICENSE.txt for license information. -// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception -//===----------------------------------------------------------------------===// - -/* This file allows to fuzz libFuzzer-style target functions - (LLVMFuzzerTestOneInput) with AFL using AFL's persistent (in-process) mode. - -Usage: -################################################################################ -cat << EOF > test_fuzzer.cc -#include <stddef.h> -#include <stdint.h> -extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) { - if (size > 0 && data[0] == 'H') - if (size > 1 && data[1] == 'I') - if (size > 2 && data[2] == '!') - __builtin_trap(); - return 0; -} -EOF -# Build your target with -fsanitize-coverage=trace-pc-guard using fresh clang. -clang -g -fsanitize-coverage=trace-pc-guard test_fuzzer.cc -c -# Build afl-llvm-rt.o.c from the AFL distribution. -clang -c -w $AFL_HOME/llvm_mode/afl-llvm-rt.o.c -# Build this file, link it with afl-llvm-rt.o.o and the target code. -clang++ afl_driver.cpp test_fuzzer.o afl-llvm-rt.o.o -# Run AFL: -rm -rf IN OUT; mkdir IN OUT; echo z > IN/z; -$AFL_HOME/afl-fuzz -i IN -o OUT ./a.out -################################################################################ -AFL_DRIVER_STDERR_DUPLICATE_FILENAME: Setting this *appends* stderr to the file -specified. If the file does not exist, it is created. This is useful for getting -stack traces (when using ASAN for example) or original error messages on hard -to reproduce bugs. Note that any content written to stderr will be written to -this file instead of stderr's usual location. - -AFL_DRIVER_CLOSE_FD_MASK: Similar to libFuzzer's -close_fd_mask behavior option. -If 1, close stdout at startup. If 2 close stderr; if 3 close both. - -*/ -#include <assert.h> -#include <errno.h> -#include <stdarg.h> -#include <stdint.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> - -#include <fstream> -#include <iostream> -#include <vector> - -#ifdef _DEBUG -#include "hash.h" -#endif - -// Platform detection. Copied from FuzzerInternal.h -#ifdef __linux__ -#define LIBFUZZER_LINUX 1 -#define LIBFUZZER_APPLE 0 -#define LIBFUZZER_NETBSD 0 -#define LIBFUZZER_FREEBSD 0 -#define LIBFUZZER_OPENBSD 0 -#elif __APPLE__ -#define LIBFUZZER_LINUX 0 -#define LIBFUZZER_APPLE 1 -#define LIBFUZZER_NETBSD 0 -#define LIBFUZZER_FREEBSD 0 -#define LIBFUZZER_OPENBSD 0 -#elif __NetBSD__ -#define LIBFUZZER_LINUX 0 -#define LIBFUZZER_APPLE 0 -#define LIBFUZZER_NETBSD 1 -#define LIBFUZZER_FREEBSD 0 -#define LIBFUZZER_OPENBSD 0 -#elif __FreeBSD__ -#define LIBFUZZER_LINUX 0 -#define LIBFUZZER_APPLE 0 -#define LIBFUZZER_NETBSD 0 -#define LIBFUZZER_FREEBSD 1 -#define LIBFUZZER_OPENBSD 0 -#elif __OpenBSD__ -#define LIBFUZZER_LINUX 0 -#define LIBFUZZER_APPLE 0 -#define LIBFUZZER_NETBSD 0 -#define LIBFUZZER_FREEBSD 0 -#define LIBFUZZER_OPENBSD 1 -#else -#error "Support for your platform has not been implemented" -#endif - -int __afl_sharedmem_fuzzing = 1; -extern unsigned int *__afl_fuzz_len; -extern unsigned char *__afl_fuzz_ptr; - -// libFuzzer interface is thin, so we don't include any libFuzzer headers. -extern "C" { -int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size); -__attribute__((weak)) int LLVMFuzzerInitialize(int *argc, char ***argv); -} - -// Notify AFL about persistent mode. -static volatile char AFL_PERSISTENT[] = "##SIG_AFL_PERSISTENT##"; -extern "C" int __afl_persistent_loop(unsigned int); -static volatile char suppress_warning2 = AFL_PERSISTENT[0]; - -// Notify AFL about deferred forkserver. -static volatile char AFL_DEFER_FORKSVR[] = "##SIG_AFL_DEFER_FORKSRV##"; -extern "C" void __afl_manual_init(); -static volatile char suppress_warning1 = AFL_DEFER_FORKSVR[0]; - -// Input buffer. -static const size_t kMaxAflInputSize = 1 << 20; -static uint8_t AflInputBuf[kMaxAflInputSize]; - -// Use this optionally defined function to output sanitizer messages even if -// user asks to close stderr. -__attribute__((weak)) extern "C" void __sanitizer_set_report_fd(void *); - -// Keep track of where stderr content is being written to, so that -// dup_and_close_stderr can use the correct one. -static FILE *output_file = stderr; - -// Experimental feature to use afl_driver without AFL's deferred mode. -// Needs to run before __afl_auto_init. -__attribute__((constructor(0))) static void __decide_deferred_forkserver(void) { - if (getenv("AFL_DRIVER_DONT_DEFER")) { - if (unsetenv("__AFL_DEFER_FORKSRV")) { - perror("Failed to unset __AFL_DEFER_FORKSRV"); - abort(); - } - } -} - -// If the user asks us to duplicate stderr, then do it. -static void maybe_duplicate_stderr() { - char *stderr_duplicate_filename = - getenv("AFL_DRIVER_STDERR_DUPLICATE_FILENAME"); - - if (!stderr_duplicate_filename) - return; - - FILE *stderr_duplicate_stream = - freopen(stderr_duplicate_filename, "a+", stderr); - - if (!stderr_duplicate_stream) { - fprintf( - stderr, - "Failed to duplicate stderr to AFL_DRIVER_STDERR_DUPLICATE_FILENAME"); - abort(); - } - output_file = stderr_duplicate_stream; -} - -// Most of these I/O functions were inspired by/copied from libFuzzer's code. -static void discard_output(int fd) { - FILE *temp = fopen("/dev/null", "w"); - if (!temp) - abort(); - dup2(fileno(temp), fd); - fclose(temp); -} - -static void close_stdout() { discard_output(STDOUT_FILENO); } - -// Prevent the targeted code from writing to "stderr" but allow sanitizers and -// this driver to do so. -static void dup_and_close_stderr() { - int output_fileno = fileno(output_file); - int output_fd = dup(output_fileno); - if (output_fd <= 0) - abort(); - FILE *new_output_file = fdopen(output_fd, "w"); - if (!new_output_file) - abort(); - if (!__sanitizer_set_report_fd) - return; - __sanitizer_set_report_fd(reinterpret_cast<void *>(output_fd)); - discard_output(output_fileno); -} - -static void Printf(const char *Fmt, ...) { - va_list ap; - va_start(ap, Fmt); - vfprintf(output_file, Fmt, ap); - va_end(ap); - fflush(output_file); -} - -// Close stdout and/or stderr if user asks for it. -static void maybe_close_fd_mask() { - char *fd_mask_str = getenv("AFL_DRIVER_CLOSE_FD_MASK"); - if (!fd_mask_str) - return; - int fd_mask = atoi(fd_mask_str); - if (fd_mask & 2) - dup_and_close_stderr(); - if (fd_mask & 1) - close_stdout(); -} - -// Define LLVMFuzzerMutate to avoid link failures for targets that use it -// with libFuzzer's LLVMFuzzerCustomMutator. -extern "C" size_t LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize) { - assert(false && "LLVMFuzzerMutate should not be called from afl_driver"); - return 0; -} - -// Execute any files provided as parameters. -static int ExecuteFilesOnyByOne(int argc, char **argv) { - for (int i = 1; i < argc; i++) { - std::ifstream in(argv[i], std::ios::binary); - in.seekg(0, in.end); - size_t length = in.tellg(); - in.seekg (0, in.beg); - std::cout << "Reading " << length << " bytes from " << argv[i] << std::endl; - // Allocate exactly length bytes so that we reliably catch buffer overflows. - std::vector<char> bytes(length); - in.read(bytes.data(), bytes.size()); - assert(in); - LLVMFuzzerTestOneInput(reinterpret_cast<const uint8_t *>(bytes.data()), - bytes.size()); - std::cout << "Execution successful" << std::endl; - } - return 0; -} - -int main(int argc, char **argv) { - Printf( - "======================= INFO =========================\n" - "This binary is built for AFL-fuzz.\n" - "To run the target function on individual input(s) execute this:\n" - " %s < INPUT_FILE\n" - "or\n" - " %s INPUT_FILE1 [INPUT_FILE2 ... ]\n" - "To fuzz with afl-fuzz execute this:\n" - " afl-fuzz [afl-flags] %s [-N]\n" - "afl-fuzz will run N iterations before " - "re-spawning the process (default: 1000)\n" - "======================================================\n", - argv[0], argv[0], argv[0]); - - maybe_duplicate_stderr(); - maybe_close_fd_mask(); - if (LLVMFuzzerInitialize) - LLVMFuzzerInitialize(&argc, &argv); - // Do any other expensive one-time initialization here. - - uint8_t dummy_input[1] = {0}; - int N = 100000; - if (argc == 2 && argv[1][0] == '-') - N = atoi(argv[1] + 1); - else if(argc == 2 && (N = atoi(argv[1])) > 0) - Printf("WARNING: using the deprecated call style `%s %d`\n", argv[0], N); - else if (argc > 1) { -// if (!getenv("AFL_DRIVER_DONT_DEFER")) { - __afl_sharedmem_fuzzing = 0; - __afl_manual_init(); -// } - return ExecuteFilesOnyByOne(argc, argv); - exit(0); - } - - assert(N > 0); - -// if (!getenv("AFL_DRIVER_DONT_DEFER")) - __afl_manual_init(); - - // Call LLVMFuzzerTestOneInput here so that coverage caused by initialization - // on the first execution of LLVMFuzzerTestOneInput is ignored. - LLVMFuzzerTestOneInput(dummy_input, 1); - - int num_runs = 0; - while (__afl_persistent_loop(N)) { -#ifdef _DEBUG - fprintf(stderr, "CLIENT crc: %016llx len: %u\n", hash64(__afl_fuzz_ptr, *__afl_fuzz_len, 0xa5b35705), *__afl_fuzz_len); - fprintf(stderr, "RECV:"); - for (int i = 0; i < *__afl_fuzz_len; i++) - fprintf(stderr, "%02x", __afl_fuzz_ptr[i]); - fprintf(stderr,"\n"); -#endif - if (*__afl_fuzz_len) { - num_runs++; - LLVMFuzzerTestOneInput(__afl_fuzz_ptr, *__afl_fuzz_len); - } - } - Printf("%s: successfully executed %d input(s)\n", argv[0], num_runs); -} |