| /* |
| american fuzzy lop++ - LLVM-mode wrapper for clang |
| ------------------------------------------------ |
| |
| Written by Laszlo Szekeres <lszekeres@google.com> and |
| Michal Zalewski |
| |
| LLVM integration design comes from Laszlo Szekeres. |
| |
| Copyright 2015, 2016 Google Inc. All rights reserved. |
| Copyright 2019-2020 AFLplusplus Project. All rights reserved. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at: |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| This program is a drop-in replacement for clang, similar in most respects |
| to ../afl-gcc. It tries to figure out compilation mode, adds a bunch |
| of flags, and then calls the real compiler. |
| |
| */ |
| |
| #define AFL_MAIN |
| |
| #include "common.h" |
| #include "config.h" |
| #include "types.h" |
| #include "debug.h" |
| #include "alloc-inl.h" |
| #include "llvm-ngram-coverage.h" |
| |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <strings.h> |
| #include <limits.h> |
| #include <assert.h> |
| |
| static u8 * obj_path; /* Path to runtime libraries */ |
| static u8 **cc_params; /* Parameters passed to the real CC */ |
| static u32 cc_par_cnt = 1; /* Param count, including argv0 */ |
| static u8 llvm_fullpath[PATH_MAX]; |
| static u8 instrument_mode, instrument_opt_mode, ngram_size, lto_mode, cpp_mode; |
| static u8 *lto_flag = AFL_CLANG_FLTO; |
| static u8 *march_opt = CFLAGS_OPT; |
| static u8 debug; |
| static u8 cwd[4096]; |
| static u8 cmplog_mode; |
| u8 use_stdin = 0; /* dummy */ |
| |
| enum { |
| |
| INSTURMENT_DEFAULT = 0, |
| INSTRUMENT_CLASSIC = 1, |
| INSTRUMENT_AFL = 1, |
| INSTRUMENT_PCGUARD = 2, |
| INSTRUMENT_INSTRIM = 3, |
| INSTRUMENT_CFG = 3, |
| INSTRUMENT_LTO = 4, |
| INSTRUMENT_OPT_CTX = 8, |
| INSTRUMENT_OPT_NGRAM = 16 |
| |
| }; |
| |
| char instrument_mode_string[18][18] = { |
| |
| "DEFAULT", "CLASSIC", "PCGUARD", "CFG", "LTO", "", "", "", "CTX", "", |
| "", "", "", "", "", "", "NGRAM", "" |
| |
| }; |
| |
| u8 *getthecwd() { |
| |
| static u8 fail[] = ""; |
| if (getcwd(cwd, sizeof(cwd)) == NULL) return fail; |
| return cwd; |
| |
| } |
| |
| /* Try to find the runtime libraries. If that fails, abort. */ |
| |
| static void find_obj(u8 *argv0) { |
| |
| u8 *afl_path = getenv("AFL_PATH"); |
| u8 *slash, *tmp; |
| |
| if (afl_path) { |
| |
| #ifdef __ANDROID__ |
| tmp = alloc_printf("%s/afl-llvm-rt.so", afl_path); |
| #else |
| tmp = alloc_printf("%s/afl-llvm-rt.o", afl_path); |
| #endif |
| |
| if (!access(tmp, R_OK)) { |
| |
| obj_path = afl_path; |
| ck_free(tmp); |
| return; |
| |
| } |
| |
| ck_free(tmp); |
| |
| } |
| |
| slash = strrchr(argv0, '/'); |
| |
| if (slash) { |
| |
| u8 *dir; |
| |
| *slash = 0; |
| dir = ck_strdup(argv0); |
| *slash = '/'; |
| |
| #ifdef __ANDROID__ |
| tmp = alloc_printf("%s/afl-llvm-rt.so", dir); |
| #else |
| tmp = alloc_printf("%s/afl-llvm-rt.o", dir); |
| #endif |
| |
| if (!access(tmp, R_OK)) { |
| |
| obj_path = dir; |
| ck_free(tmp); |
| return; |
| |
| } |
| |
| ck_free(tmp); |
| ck_free(dir); |
| |
| } |
| |
| #ifdef __ANDROID__ |
| if (!access(AFL_PATH "/afl-llvm-rt.so", R_OK)) { |
| |
| #else |
| if (!access(AFL_PATH "/afl-llvm-rt.o", R_OK)) { |
| |
| #endif |
| |
| obj_path = AFL_PATH; |
| return; |
| |
| } |
| |
| FATAL( |
| "Unable to find 'afl-llvm-rt.o' or 'afl-llvm-pass.so'. Please set " |
| "AFL_PATH"); |
| |
| } |
| |
| /* Copy argv to cc_params, making the necessary edits. */ |
| |
| static void edit_params(u32 argc, char **argv, char **envp) { |
| |
| u8 fortify_set = 0, asan_set = 0, x_set = 0, bit_mode = 0; |
| u8 *name; |
| |
| cc_params = ck_alloc((argc + 128) * sizeof(u8 *)); |
| |
| name = strrchr(argv[0], '/'); |
| if (!name) |
| name = argv[0]; |
| else |
| ++name; |
| |
| if (lto_mode) |
| if (lto_flag[0] != '-') |
| FATAL( |
| "Using afl-clang-lto is not possible because Makefile magic did not " |
| "identify the correct -flto flag"); |
| |
| if (!strcmp(name, "afl-clang-fast++") || !strcmp(name, "afl-clang-lto++")) { |
| |
| u8 *alt_cxx = getenv("AFL_CXX"); |
| if (USE_BINDIR) |
| snprintf(llvm_fullpath, sizeof(llvm_fullpath), "%s/clang++", LLVM_BINDIR); |
| else |
| sprintf(llvm_fullpath, CLANGPP_BIN); |
| cc_params[0] = alt_cxx && *alt_cxx ? alt_cxx : (u8 *)llvm_fullpath; |
| cpp_mode = 1; |
| |
| } else if (!strcmp(name, "afl-clang-fast") || |
| |
| !strcmp(name, "afl-clang-lto")) { |
| |
| u8 *alt_cc = getenv("AFL_CC"); |
| if (USE_BINDIR) |
| snprintf(llvm_fullpath, sizeof(llvm_fullpath), "%s/clang", LLVM_BINDIR); |
| else |
| sprintf(llvm_fullpath, CLANG_BIN); |
| cc_params[0] = alt_cc && *alt_cc ? alt_cc : (u8 *)llvm_fullpath; |
| |
| } else { |
| |
| fprintf(stderr, "Name of the binary: %s\n", argv[0]); |
| FATAL( |
| "Name of the binary is not a known name, expected afl-clang-fast(++) " |
| "or afl-clang-lto(++)"); |
| |
| } |
| |
| if (lto_mode && cpp_mode) |
| cc_params[cc_par_cnt++] = "-lc++"; // needed by fuzzbench, early |
| |
| /* There are several ways to compile with afl-clang-fast. In the traditional |
| mode, we use afl-llvm-pass.so, then there is libLLVMInsTrim.so which is |
| faster and creates less map pollution. |
| Then there is the 'trace-pc-guard' mode, we use native LLVM |
| instrumentation callbacks instead. For trace-pc-guard see: |
| http://clang.llvm.org/docs/SanitizerCoverage.html#tracing-pcs-with-guards |
| The best instrumentatation is with the LTO modes, the classic and |
| InsTrimLTO, the latter is faster. The LTO modes are activated by using |
| afl-clang-lto(++) |
| */ |
| |
| if (lto_mode) { |
| |
| if (getenv("AFL_LLVM_WHITELIST") != NULL) { |
| |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = "-load"; |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/afl-llvm-lto-whitelist.so", obj_path); |
| |
| } |
| |
| } |
| |
| // laf |
| if (getenv("LAF_SPLIT_SWITCHES") || getenv("AFL_LLVM_LAF_SPLIT_SWITCHES")) { |
| |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = "-load"; |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/split-switches-pass.so", obj_path); |
| |
| } |
| |
| if (getenv("LAF_TRANSFORM_COMPARES") || |
| getenv("AFL_LLVM_LAF_TRANSFORM_COMPARES")) { |
| |
| if (!be_quiet && getenv("AFL_LLVM_LTO_AUTODICTIONARY") && lto_mode) |
| WARNF( |
| "using AFL_LLVM_LAF_TRANSFORM_COMPARES together with " |
| "AFL_LLVM_LTO_AUTODICTIONARY makes no sense. Use only " |
| "AFL_LLVM_LTO_AUTODICTIONARY."); |
| |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = "-load"; |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/compare-transform-pass.so", obj_path); |
| |
| } |
| |
| if (getenv("LAF_SPLIT_COMPARES") || getenv("AFL_LLVM_LAF_SPLIT_COMPARES")) { |
| |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = "-load"; |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/split-compares-pass.so", obj_path); |
| |
| } |
| |
| // /laf |
| |
| unsetenv("AFL_LD"); |
| unsetenv("AFL_LD_CALLER"); |
| if (cmplog_mode) { |
| |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = "-load"; |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/cmplog-routines-pass.so", obj_path); |
| |
| // reuse split switches from laf |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = "-load"; |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/split-switches-pass.so", obj_path); |
| |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = "-load"; |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/cmplog-instructions-pass.so", obj_path); |
| |
| cc_params[cc_par_cnt++] = "-fno-inline"; |
| |
| } |
| |
| if (lto_mode) { |
| |
| cc_params[cc_par_cnt++] = alloc_printf("-fuse-ld=%s", AFL_REAL_LD); |
| cc_params[cc_par_cnt++] = "-Wl,--allow-multiple-definition"; |
| if (instrument_mode == INSTRUMENT_CFG) |
| cc_params[cc_par_cnt++] = |
| alloc_printf("-Wl,-mllvm=-load=%s/afl-llvm-lto-instrim.so", obj_path); |
| else |
| cc_params[cc_par_cnt++] = alloc_printf( |
| "-Wl,-mllvm=-load=%s/afl-llvm-lto-instrumentation.so", obj_path); |
| cc_params[cc_par_cnt++] = lto_flag; |
| |
| } else { |
| |
| if (instrument_mode == INSTRUMENT_PCGUARD) { |
| |
| cc_params[cc_par_cnt++] = |
| "-fsanitize-coverage=trace-pc-guard"; // edge coverage by default |
| |
| } else { |
| |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| cc_params[cc_par_cnt++] = "-load"; |
| cc_params[cc_par_cnt++] = "-Xclang"; |
| if (instrument_mode == INSTRUMENT_CFG) |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/libLLVMInsTrim.so", obj_path); |
| else |
| cc_params[cc_par_cnt++] = alloc_printf("%s/afl-llvm-pass.so", obj_path); |
| |
| } |
| |
| } |
| |
| cc_params[cc_par_cnt++] = "-Qunused-arguments"; |
| |
| // in case LLVM is installed not via a package manager or "make install" |
| // e.g. compiled download or compiled from github then it's ./lib directory |
| // might not be in the search path. Add it if so. |
| u8 *libdir = strdup(LLVM_LIBDIR); |
| if (cpp_mode && strlen(libdir) && strncmp(libdir, "/usr", 4) && |
| strncmp(libdir, "/lib", 4)) { |
| |
| cc_params[cc_par_cnt++] = "-rpath"; |
| cc_params[cc_par_cnt++] = libdir; |
| |
| } else { |
| |
| free(libdir); |
| |
| } |
| |
| /* Detect stray -v calls from ./configure scripts. */ |
| |
| while (--argc) { |
| |
| u8 *cur = *(++argv); |
| |
| if (!strcmp(cur, "-m32")) bit_mode = 32; |
| if (!strcmp(cur, "armv7a-linux-androideabi")) bit_mode = 32; |
| if (!strcmp(cur, "-m64")) bit_mode = 64; |
| |
| if (!strcmp(cur, "-x")) x_set = 1; |
| |
| if (!strcmp(cur, "-fsanitize=address") || !strcmp(cur, "-fsanitize=memory")) |
| asan_set = 1; |
| |
| if (strstr(cur, "FORTIFY_SOURCE")) fortify_set = 1; |
| |
| if (!strcmp(cur, "-Wl,-z,defs") || !strcmp(cur, "-Wl,--no-undefined")) |
| continue; |
| |
| cc_params[cc_par_cnt++] = cur; |
| |
| } |
| |
| if (getenv("AFL_HARDEN")) { |
| |
| cc_params[cc_par_cnt++] = "-fstack-protector-all"; |
| |
| if (!fortify_set) cc_params[cc_par_cnt++] = "-D_FORTIFY_SOURCE=2"; |
| |
| } |
| |
| if (!asan_set) { |
| |
| if (getenv("AFL_USE_ASAN")) { |
| |
| if (getenv("AFL_USE_MSAN")) FATAL("ASAN and MSAN are mutually exclusive"); |
| |
| if (getenv("AFL_HARDEN")) |
| FATAL("ASAN and AFL_HARDEN are mutually exclusive"); |
| |
| cc_params[cc_par_cnt++] = "-U_FORTIFY_SOURCE"; |
| cc_params[cc_par_cnt++] = "-fsanitize=address"; |
| |
| } else if (getenv("AFL_USE_MSAN")) { |
| |
| if (getenv("AFL_USE_ASAN")) FATAL("ASAN and MSAN are mutually exclusive"); |
| |
| if (getenv("AFL_HARDEN")) |
| FATAL("MSAN and AFL_HARDEN are mutually exclusive"); |
| |
| cc_params[cc_par_cnt++] = "-U_FORTIFY_SOURCE"; |
| cc_params[cc_par_cnt++] = "-fsanitize=memory"; |
| |
| } |
| |
| } |
| |
| if (getenv("AFL_USE_UBSAN")) { |
| |
| cc_params[cc_par_cnt++] = "-fsanitize=undefined"; |
| cc_params[cc_par_cnt++] = "-fsanitize-undefined-trap-on-error"; |
| cc_params[cc_par_cnt++] = "-fno-sanitize-recover=all"; |
| |
| } |
| |
| if (getenv("AFL_USE_CFISAN")) { |
| |
| if (!lto_mode) { |
| |
| uint32_t i = 0, found = 0; |
| while (envp[i] != NULL && !found) |
| if (strncmp("-flto", envp[i++], 5) == 0) found = 1; |
| if (!found) cc_params[cc_par_cnt++] = "-flto"; |
| |
| } |
| |
| cc_params[cc_par_cnt++] = "-fsanitize=cfi"; |
| cc_params[cc_par_cnt++] = "-fvisibility=hidden"; |
| |
| } |
| |
| if (!getenv("AFL_DONT_OPTIMIZE")) { |
| |
| cc_params[cc_par_cnt++] = "-g"; |
| cc_params[cc_par_cnt++] = "-O3"; |
| cc_params[cc_par_cnt++] = "-funroll-loops"; |
| if (strlen(march_opt) > 1 && march_opt[0] == '-') |
| cc_params[cc_par_cnt++] = march_opt; |
| |
| } |
| |
| if (getenv("AFL_NO_BUILTIN") || getenv("AFL_LLVM_LAF_TRANSFORM_COMPARES") || |
| getenv("LAF_TRANSFORM_COMPARES") || |
| (lto_mode && (getenv("AFL_LLVM_LTO_AUTODICTIONARY") || |
| getenv("AFL_LLVM_AUTODICTIONARY")))) { |
| |
| cc_params[cc_par_cnt++] = "-fno-builtin-strcmp"; |
| cc_params[cc_par_cnt++] = "-fno-builtin-strncmp"; |
| cc_params[cc_par_cnt++] = "-fno-builtin-strcasecmp"; |
| cc_params[cc_par_cnt++] = "-fno-builtin-strncasecmp"; |
| cc_params[cc_par_cnt++] = "-fno-builtin-memcmp"; |
| cc_params[cc_par_cnt++] = "-fno-builtin-bcmp"; |
| cc_params[cc_par_cnt++] = "-fno-builtin-strstr"; |
| cc_params[cc_par_cnt++] = "-fno-builtin-strcasestr"; |
| |
| } |
| |
| #ifdef USEMMAP |
| cc_params[cc_par_cnt++] = "-lrt"; |
| #endif |
| |
| cc_params[cc_par_cnt++] = "-D__AFL_HAVE_MANUAL_CONTROL=1"; |
| cc_params[cc_par_cnt++] = "-D__AFL_COMPILER=1"; |
| cc_params[cc_par_cnt++] = "-DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION=1"; |
| |
| /* When the user tries to use persistent or deferred forkserver modes by |
| appending a single line to the program, we want to reliably inject a |
| signature into the binary (to be picked up by afl-fuzz) and we want |
| to call a function from the runtime .o file. This is unnecessarily |
| painful for three reasons: |
| |
| 1) We need to convince the compiler not to optimize out the signature. |
| This is done with __attribute__((used)). |
| |
| 2) We need to convince the linker, when called with -Wl,--gc-sections, |
| not to do the same. This is done by forcing an assignment to a |
| 'volatile' pointer. |
| |
| 3) We need to declare __afl_persistent_loop() in the global namespace, |
| but doing this within a method in a class is hard - :: and extern "C" |
| are forbidden and __attribute__((alias(...))) doesn't work. Hence the |
| __asm__ aliasing trick. |
| |
| */ |
| |
| cc_params[cc_par_cnt++] = |
| "-D__AFL_FUZZ_INIT()=" |
| "int __afl_sharedmem_fuzzing = 1;" |
| "extern unsigned int __afl_fuzz_len;" |
| "extern unsigned char *__afl_fuzz_ptr;"; |
| cc_params[cc_par_cnt++] = "-D__AFL_FUZZ_TESTCASE_BUF=__afl_fuzz_ptr"; |
| cc_params[cc_par_cnt++] = "-D__AFL_FUZZ_TESTCASE_LEN=__afl_fuzz_len"; |
| |
| cc_params[cc_par_cnt++] = |
| "-D__AFL_LOOP(_A)=" |
| "({ static volatile char *_B __attribute__((used)); " |
| " _B = (char*)\"" PERSIST_SIG |
| "\"; " |
| #ifdef __APPLE__ |
| "__attribute__((visibility(\"default\"))) " |
| "int _L(unsigned int) __asm__(\"___afl_persistent_loop\"); " |
| #else |
| "__attribute__((visibility(\"default\"))) " |
| "int _L(unsigned int) __asm__(\"__afl_persistent_loop\"); " |
| #endif /* ^__APPLE__ */ |
| "_L(_A); })"; |
| |
| cc_params[cc_par_cnt++] = |
| "-D__AFL_INIT()=" |
| "do { static volatile char *_A __attribute__((used)); " |
| " _A = (char*)\"" DEFER_SIG |
| "\"; " |
| #ifdef __APPLE__ |
| "__attribute__((visibility(\"default\"))) " |
| "void _I(void) __asm__(\"___afl_manual_init\"); " |
| #else |
| "__attribute__((visibility(\"default\"))) " |
| "void _I(void) __asm__(\"__afl_manual_init\"); " |
| #endif /* ^__APPLE__ */ |
| "_I(); } while (0)"; |
| |
| if (x_set) { |
| |
| cc_params[cc_par_cnt++] = "-x"; |
| cc_params[cc_par_cnt++] = "none"; |
| |
| } |
| |
| #ifndef __ANDROID__ |
| switch (bit_mode) { |
| |
| case 0: |
| cc_params[cc_par_cnt++] = alloc_printf("%s/afl-llvm-rt.o", obj_path); |
| if (lto_mode) |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/afl-llvm-rt-lto.o", obj_path); |
| break; |
| |
| case 32: |
| cc_params[cc_par_cnt++] = alloc_printf("%s/afl-llvm-rt-32.o", obj_path); |
| if (access(cc_params[cc_par_cnt - 1], R_OK)) |
| FATAL("-m32 is not supported by your compiler"); |
| if (lto_mode) { |
| |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/afl-llvm-rt-lto-32.o", obj_path); |
| if (access(cc_params[cc_par_cnt - 1], R_OK)) |
| FATAL("-m32 is not supported by your compiler"); |
| |
| } |
| |
| break; |
| |
| case 64: |
| cc_params[cc_par_cnt++] = alloc_printf("%s/afl-llvm-rt-64.o", obj_path); |
| if (access(cc_params[cc_par_cnt - 1], R_OK)) |
| FATAL("-m64 is not supported by your compiler"); |
| if (lto_mode) { |
| |
| cc_params[cc_par_cnt++] = |
| alloc_printf("%s/afl-llvm-rt-lto-64.o", obj_path); |
| if (access(cc_params[cc_par_cnt - 1], R_OK)) |
| FATAL("-m64 is not supported by your compiler"); |
| |
| } |
| |
| break; |
| |
| } |
| |
| #endif |
| |
| cc_params[cc_par_cnt] = NULL; |
| |
| } |
| |
| /* Main entry point */ |
| |
| int main(int argc, char **argv, char **envp) { |
| |
| int i; |
| char *callname = "afl-clang-fast", *ptr = NULL; |
| |
| if (getenv("AFL_DEBUG")) { |
| |
| debug = 1; |
| if (strcmp(getenv("AFL_DEBUG"), "0") == 0) unsetenv("AFL_DEBUG"); |
| |
| } else if (getenv("AFL_QUIET")) |
| |
| be_quiet = 1; |
| |
| if (getenv("USE_TRACE_PC") || getenv("AFL_USE_TRACE_PC") || |
| getenv("AFL_LLVM_USE_TRACE_PC") || getenv("AFL_TRACE_PC")) { |
| |
| if (instrument_mode == 0) |
| instrument_mode = INSTRUMENT_PCGUARD; |
| else if (instrument_mode != INSTRUMENT_PCGUARD) |
| FATAL("you can not set AFL_LLVM_INSTRUMENT and AFL_TRACE_PC together"); |
| |
| } |
| |
| if (getenv("AFL_LLVM_INSTRIM") || getenv("INSTRIM") || |
| getenv("INSTRIM_LIB")) { |
| |
| if (instrument_mode == 0) |
| instrument_mode = INSTRUMENT_CFG; |
| else if (instrument_mode != INSTRUMENT_CFG) |
| FATAL( |
| "you can not set AFL_LLVM_INSTRUMENT and AFL_LLVM_INSTRIM together"); |
| |
| } |
| |
| if (getenv("AFL_LLVM_CTX")) instrument_opt_mode |= INSTRUMENT_OPT_CTX; |
| |
| if (getenv("AFL_LLVM_NGRAM_SIZE")) { |
| |
| instrument_opt_mode |= INSTRUMENT_OPT_NGRAM; |
| ngram_size = atoi(getenv("AFL_LLVM_NGRAM_SIZE")); |
| if (ngram_size < 2 || ngram_size > NGRAM_SIZE_MAX) |
| FATAL( |
| "NGRAM instrumentation mode must be between 2 and NGRAM_SIZE_MAX " |
| "(%u)", |
| NGRAM_SIZE_MAX); |
| |
| } |
| |
| if (getenv("AFL_LLVM_INSTRUMENT")) { |
| |
| u8 *ptr = strtok(getenv("AFL_LLVM_INSTRUMENT"), ":,;"); |
| |
| while (ptr) { |
| |
| if (strncasecmp(ptr, "afl", strlen("afl")) == 0 || |
| strncasecmp(ptr, "classic", strlen("classic")) == 0) { |
| |
| if (!instrument_mode || instrument_mode == INSTRUMENT_AFL) |
| instrument_mode = INSTRUMENT_AFL; |
| else |
| FATAL("main instrumentation mode already set with %s", |
| instrument_mode_string[instrument_mode]); |
| |
| } |
| |
| if (strncasecmp(ptr, "pc-guard", strlen("pc-guard")) == 0 || |
| strncasecmp(ptr, "pcguard", strlen("pcgard")) == 0) { |
| |
| if (!instrument_mode || instrument_mode == INSTRUMENT_PCGUARD) |
| instrument_mode = INSTRUMENT_PCGUARD; |
| else |
| FATAL("main instrumentation mode already set with %s", |
| instrument_mode_string[instrument_mode]); |
| |
| } |
| |
| if (strncasecmp(ptr, "cfg", strlen("cfg")) == 0 || |
| strncasecmp(ptr, "instrim", strlen("instrim")) == 0) { |
| |
| if (instrument_mode == INSTRUMENT_LTO) { |
| |
| instrument_mode = INSTRUMENT_CFG; |
| lto_mode = 1; |
| |
| } else if (!instrument_mode || instrument_mode == INSTRUMENT_CFG) |
| |
| instrument_mode = INSTRUMENT_CFG; |
| else |
| FATAL("main instrumentation mode already set with %s", |
| instrument_mode_string[instrument_mode]); |
| |
| } |
| |
| if (strncasecmp(ptr, "lto", strlen("lto")) == 0) { |
| |
| lto_mode = 1; |
| if (!instrument_mode || instrument_mode == INSTRUMENT_LTO) |
| instrument_mode = INSTRUMENT_LTO; |
| else if (instrument_mode != INSTRUMENT_CFG) |
| FATAL("main instrumentation mode already set with %s", |
| instrument_mode_string[instrument_mode]); |
| |
| } |
| |
| if (strncasecmp(ptr, "ctx", strlen("ctx")) == 0) { |
| |
| instrument_opt_mode |= INSTRUMENT_OPT_CTX; |
| setenv("AFL_LLVM_CTX", "1", 1); |
| |
| } |
| |
| if (strncasecmp(ptr, "ngram", strlen("ngram")) == 0) { |
| |
| ptr += strlen("ngram"); |
| while (*ptr && (*ptr < '0' || *ptr > '9')) |
| ptr++; |
| if (!*ptr) |
| if ((ptr = getenv("AFL_LLVM_NGRAM_SIZE")) != NULL) |
| FATAL( |
| "you must set the NGRAM size with (e.g. for value 2) " |
| "AFL_LLVM_INSTRUMENT=ngram-2"); |
| ngram_size = atoi(ptr); |
| if (ngram_size < 2 || ngram_size > NGRAM_SIZE_MAX) |
| FATAL( |
| "NGRAM instrumentation option must be between 2 and " |
| "NGRAM_SIZE_MAX " |
| "(%u)", |
| NGRAM_SIZE_MAX); |
| instrument_opt_mode |= (INSTRUMENT_OPT_NGRAM); |
| ptr = alloc_printf("%u", ngram_size); |
| setenv("AFL_LLVM_NGRAM_SIZE", ptr, 1); |
| |
| } |
| |
| ptr = strtok(NULL, ":,;"); |
| |
| } |
| |
| } |
| |
| if (strstr(argv[0], "afl-clang-lto") != NULL) { |
| |
| if (instrument_mode == 0 || instrument_mode == INSTRUMENT_LTO || |
| instrument_mode == INSTRUMENT_CFG) { |
| |
| lto_mode = 1; |
| callname = "afl-clang-lto"; |
| if (!instrument_mode) { |
| |
| instrument_mode = INSTRUMENT_LTO; |
| ptr = instrument_mode_string[instrument_mode]; |
| |
| } |
| |
| } else { |
| |
| if (!be_quiet) |
| WARNF("afl-clang-lto called with mode %s, using that mode instead", |
| instrument_mode_string[instrument_mode]); |
| |
| } |
| |
| } |
| |
| if (instrument_mode == 0) { |
| |
| #ifndef USE_TRACE_PC |
| if (getenv("AFL_LLVM_WHITELIST")) |
| instrument_mode = INSTRUMENT_AFL; |
| else |
| #endif |
| instrument_mode = INSTRUMENT_PCGUARD; |
| |
| } |
| |
| if (instrument_opt_mode && lto_mode) |
| FATAL( |
| "CTX and NGRAM can not be used in LTO mode (and would make LTO " |
| "useless)"); |
| |
| if (!instrument_opt_mode) { |
| |
| if (lto_mode && instrument_mode == INSTRUMENT_CFG) |
| ptr = alloc_printf("InsTrimLTO"); |
| else |
| ptr = instrument_mode_string[instrument_mode]; |
| |
| } else if (instrument_opt_mode == INSTRUMENT_OPT_CTX) |
| |
| ptr = alloc_printf("%s + CTX", instrument_mode_string[instrument_mode]); |
| else if (instrument_opt_mode == INSTRUMENT_OPT_NGRAM) |
| ptr = alloc_printf("%s + NGRAM-%u", instrument_mode_string[instrument_mode], |
| ngram_size); |
| else |
| ptr = alloc_printf("%s + CTX + NGRAM-%u", |
| instrument_mode_string[instrument_mode], ngram_size); |
| |
| #ifndef AFL_CLANG_FLTO |
| if (lto_mode) |
| FATAL( |
| "instrumentation mode LTO specified but LLVM support not available " |
| "(requires LLVM 11 or higher)"); |
| #endif |
| |
| if (instrument_opt_mode && instrument_mode != INSTRUMENT_CLASSIC && |
| instrument_mode != INSTRUMENT_CFG) |
| FATAL( |
| "CTX and NGRAM instrumentation options can only be used with CFG " |
| "(recommended) and CLASSIC instrumentation modes!"); |
| |
| if (getenv("AFL_LLVM_SKIP_NEVERZERO") && getenv("AFL_LLVM_NOT_ZERO")) |
| FATAL( |
| "AFL_LLVM_NOT_ZERO and AFL_LLVM_SKIP_NEVERZERO can not be set " |
| "together"); |
| |
| if (instrument_mode == INSTRUMENT_PCGUARD && getenv("AFL_LLVM_WHITELIST")) |
| WARNF("Instrumentation type PCGUARD does not support AFL_LLVM_WHITELIST!"); |
| |
| if (argc < 2 || strcmp(argv[1], "-h") == 0) { |
| |
| if (!lto_mode) |
| printf("afl-clang-fast" VERSION " by <lszekeres@google.com> in %s mode\n", |
| ptr); |
| else |
| printf("afl-clang-lto" VERSION |
| " by Marc \"vanHauser\" Heuse <mh@mh-sec.de> in %s mode\n", |
| ptr); |
| |
| SAYF( |
| "\n" |
| "%s[++] [options]\n" |
| "\n" |
| "This is a helper application for afl-fuzz. It serves as a drop-in " |
| "replacement\n" |
| "for clang, letting you recompile third-party code with the " |
| "required " |
| "runtime\n" |
| "instrumentation. A common use pattern would be one of the " |
| "following:\n\n" |
| |
| " CC=%s/afl-clang-fast ./configure\n" |
| " CXX=%s/afl-clang-fast++ ./configure\n\n" |
| |
| "In contrast to the traditional afl-clang tool, this version is " |
| "implemented as\n" |
| "an LLVM pass and tends to offer improved performance with slow " |
| "programs.\n\n" |
| |
| "Environment variables used:\n" |
| "AFL_CC: path to the C compiler to use\n" |
| "AFL_CXX: path to the C++ compiler to use\n" |
| "AFL_DEBUG: enable developer debugging output\n" |
| "AFL_DONT_OPTIMIZE: disable optimization instead of -O3\n" |
| "AFL_HARDEN: adds code hardening to catch memory bugs\n" |
| "AFL_INST_RATIO: percentage of branches to instrument\n" |
| "AFL_LLVM_NOT_ZERO: use cycling trace counters that skip zero\n" |
| "AFL_LLVM_SKIP_NEVERZERO: do not skip zero on trace counters\n" |
| "AFL_LLVM_LAF_SPLIT_COMPARES: enable cascaded comparisons\n" |
| "AFL_LLVM_LAF_SPLIT_COMPARES_BITW: size limit (default 8)\n" |
| "AFL_LLVM_LAF_SPLIT_SWITCHES: casc. comp. in 'switch'\n" |
| " to cascaded comparisons\n" |
| "AFL_LLVM_LAF_SPLIT_FLOATS: transform floating point comp. to " |
| "cascaded comp.\n" |
| "AFL_LLVM_LAF_TRANSFORM_COMPARES: transform library comparison " |
| "function calls\n" |
| "AFL_LLVM_LAF_ALL: enables all LAF splits/transforms\n" |
| "AFL_LLVM_WHITELIST: enable whitelisting (selective " |
| "instrumentation)\n" |
| "AFL_NO_BUILTIN: compile for use with libtokencap.so\n" |
| "AFL_PATH: path to instrumenting pass and runtime " |
| "(afl-llvm-rt.*o)\n" |
| "AFL_QUIET: suppress verbose output\n" |
| "AFL_USE_ASAN: activate address sanitizer\n" |
| "AFL_USE_CFISAN: activate control flow sanitizer\n" |
| "AFL_USE_MSAN: activate memory sanitizer\n" |
| "AFL_USE_UBSAN: activate undefined behaviour sanitizer\n", |
| callname, BIN_PATH, BIN_PATH); |
| |
| SAYF( |
| "\nafl-clang-fast specific environment variables:\n" |
| "AFL_LLVM_CMPLOG: log operands of comparisons (RedQueen mutator)\n" |
| "AFL_LLVM_INSTRUMENT: set instrumentation mode: AFL, CFG " |
| "(INSTRIM), PCGUARD [DEFAULT], LTO, CTX, NGRAM-2 ... NGRAM-16\n" |
| " You can also use the old environment variables instead:\n" |
| " AFL_LLVM_USE_TRACE_PC: use LLVM trace-pc-guard instrumentation " |
| "[DEFAULT]\n" |
| " AFL_LLVM_INSTRIM: use light weight instrumentation InsTrim\n" |
| " AFL_LLVM_INSTRIM_LOOPHEAD: optimize loop tracing for speed (" |
| "option to INSTRIM)\n" |
| " AFL_LLVM_CTX: use context sensitive coverage\n" |
| " AFL_LLVM_NGRAM_SIZE: use ngram prev_loc count coverage\n"); |
| |
| #ifdef AFL_CLANG_FLTO |
| SAYF( |
| "\nafl-clang-lto specific environment variables:\n" |
| "AFL_LLVM_LTO_DONTWRITEID: don't write the highest ID used to a " |
| "global var\n" |
| "AFL_LLVM_LTO_STARTID: from which ID to start counting from for a " |
| "bb\n" |
| "AFL_REAL_LD: use this lld linker instead of the compiled in path\n" |
| "\nafl-clang-lto was built with linker target \"%s\" and LTO flags " |
| "\"%s\"\n" |
| "If anything fails - be sure to read README.lto.md!\n", |
| AFL_REAL_LD, AFL_CLANG_FLTO); |
| #endif |
| |
| SAYF( |
| "\nafl-clang-fast was built for llvm %s with the llvm binary path " |
| "of \"%s\".\n", |
| LLVM_VERSION, LLVM_BINDIR); |
| |
| SAYF("\n"); |
| |
| exit(1); |
| |
| } else if ((isatty(2) && !be_quiet) || |
| |
| getenv("AFL_DEBUG") != NULL) { |
| |
| if (!lto_mode) |
| |
| SAYF(cCYA "afl-clang-fast" VERSION cRST |
| " by <lszekeres@google.com> in %s mode\n", |
| ptr); |
| |
| else |
| |
| SAYF(cCYA "afl-clang-lto" VERSION cRST |
| " by Marc \"vanHauser\" Heuse <mh@mh-sec.de> in mode %s\n", |
| ptr); |
| |
| } |
| |
| u8 *ptr2; |
| if (!be_quiet && !lto_mode && |
| ((ptr2 = getenv("AFL_MAP_SIZE")) || (ptr2 = getenv("AFL_MAPSIZE")))) { |
| |
| u32 map_size = atoi(ptr2); |
| if (map_size != MAP_SIZE) |
| FATAL("AFL_MAP_SIZE is not supported by afl-clang-fast"); |
| |
| } |
| |
| if (debug) { |
| |
| SAYF(cMGN "[D]" cRST " cd \"%s\";", getthecwd()); |
| for (i = 0; i < argc; i++) |
| SAYF(" \"%s\"", argv[i]); |
| SAYF("\n"); |
| |
| } |
| |
| check_environment_vars(envp); |
| |
| if (getenv("AFL_LLVM_LAF_ALL")) { |
| |
| setenv("AFL_LLVM_LAF_SPLIT_SWITCHES", "1", 1); |
| setenv("AFL_LLVM_LAF_SPLIT_COMPARES", "1", 1); |
| setenv("AFL_LLVM_LAF_SPLIT_FLOATS", "1", 1); |
| setenv("AFL_LLVM_LAF_TRANSFORM_COMPARES", "1", 1); |
| |
| } |
| |
| cmplog_mode = getenv("AFL_CMPLOG") || getenv("AFL_LLVM_CMPLOG"); |
| if (!be_quiet && cmplog_mode) |
| printf("CmpLog mode by <andreafioraldi@gmail.com>\n"); |
| |
| #ifndef __ANDROID__ |
| find_obj(argv[0]); |
| #endif |
| |
| edit_params(argc, argv, envp); |
| |
| if (debug) { |
| |
| SAYF(cMGN "[D]" cRST " cd \"%s\";", getthecwd()); |
| for (i = 0; i < cc_par_cnt; i++) |
| SAYF(" \"%s\"", cc_params[i]); |
| SAYF("\n"); |
| |
| } |
| |
| execvp(cc_params[0], (char **)cc_params); |
| |
| FATAL("Oops, failed to execute '%s' - check your PATH", cc_params[0]); |
| |
| return 0; |
| |
| } |
| |
