diff options
Diffstat (limited to 'utils')
| -rw-r--r-- | utils/afl_untracer/afl-untracer.c | 2 | ||||
| -rw-r--r-- | utils/aflpp_driver/GNUmakefile | 4 | ||||
| -rw-r--r-- | utils/aflpp_driver/aflpp_driver.c | 80 | ||||
| -rw-r--r-- | utils/libtokencap/libtokencap.so.c | 6 | ||||
| -rw-r--r-- | utils/socket_fuzzing/socketfuzz.c | 3 | ||||
| -rw-r--r-- | utils/target_intelligence/README.md | 61 |
6 files changed, 121 insertions, 35 deletions
diff --git a/utils/afl_untracer/afl-untracer.c b/utils/afl_untracer/afl-untracer.c index a18e314e..e1038212 100644 --- a/utils/afl_untracer/afl-untracer.c +++ b/utils/afl_untracer/afl-untracer.c @@ -288,7 +288,7 @@ library_list_t *find_library(char *name) { #pragma GCC optimize("O0") void breakpoint(void) { - if (debug) fprintf(stderr, "Breakpoint function \"breakpoint\" reached.\n"); + if (debug) fprintf(stderr, "Breakpoint function \"breakpoint\" reached.\n"); } diff --git a/utils/aflpp_driver/GNUmakefile b/utils/aflpp_driver/GNUmakefile index 409789cb..b973f96a 100644 --- a/utils/aflpp_driver/GNUmakefile +++ b/utils/aflpp_driver/GNUmakefile @@ -20,10 +20,6 @@ endif CFLAGS := -O3 -funroll-loops -g -fPIC -ifdef MAGMA_PATCH - CFLAGS += -DMAGMA_PATCH -endif - all: libAFLDriver.a libAFLQemuDriver.a aflpp_qemu_driver_hook.so aflpp_driver.o: aflpp_driver.c diff --git a/utils/aflpp_driver/aflpp_driver.c b/utils/aflpp_driver/aflpp_driver.c index b92e68e9..4e8f466d 100644 --- a/utils/aflpp_driver/aflpp_driver.c +++ b/utils/aflpp_driver/aflpp_driver.c @@ -1,12 +1,16 @@ -//===- afl_driver.cpp - a glue between AFL++ and libFuzzer ------*- C++ -* ===// -//===----------------------------------------------------------------------===// +// +// afl_driver.cpp - a glue between AFL++ and LLVMFuzzerTestOneInput harnesses +// -/* This file allows to fuzz libFuzzer-style target functions +/* + + This file allows to fuzz libFuzzer-style target functions (LLVMFuzzerTestOneInput) with AFL++ using persistent in-memory fuzzing. Usage: -################################################################################ -cat << EOF > test_fuzzer.cc + +# Example target: +$ cat << EOF > test_fuzzer.cc #include <stddef.h> #include <stdint.h> extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) { @@ -20,18 +24,20 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) { } EOF -# Build your target with -fsanitize-coverage=trace-pc-guard using fresh clang. -clang -c aflpp_driver.c -# Build afl-compiler-rt.o.c from the AFL distribution. -clang -c $AFL_HOME/instrumentation/afl-compiler-rt.o.c -# Build this file, link it with afl-compiler-rt.o.o and the target code. -afl-clang-fast -o test_fuzzer test_fuzzer.cc afl-compiler-rt.o aflpp_driver.o + +# Build your target with afl-cc -fsanitize=fuzzer +$ afl-c++ -fsanitize=fuzzer -o test_fuzzer test_fuzzer.cc # Run AFL: -rm -rf IN OUT; mkdir IN OUT; echo z > IN/z; -$AFL_HOME/afl-fuzz -i IN -o OUT ./a.out -################################################################################ +$ mkdir -p in ; echo z > in/foo; +$ afl-fuzz -i in -o out -- ./test_fuzzer + */ +#ifdef __cplusplus +extern "C" { + +#endif + #include <assert.h> #include <errno.h> #include <stdarg.h> @@ -58,12 +64,8 @@ $AFL_HOME/afl-fuzz -i IN -o OUT ./a.out #include "hash.h" #endif -#ifdef MAGMA_PATCH -int __afl_sharedmem_fuzzing = 0; -#else // AFL++ shared memory fuzz cases int __afl_sharedmem_fuzzing = 1; -#endif extern unsigned int *__afl_fuzz_len; extern unsigned char *__afl_fuzz_ptr; @@ -72,11 +74,14 @@ extern unsigned char *__afl_area_ptr; extern unsigned int __afl_map_size; // libFuzzer interface is thin, so we don't include any libFuzzer headers. -__attribute__((weak)) int LLVMFuzzerTestOneInput(const uint8_t *Data, - size_t Size); -__attribute__((weak)) int LLVMFuzzerInitialize(int *argc, char ***argv); -int LLVMFuzzerRunDriver(int *argc, char ***argv, - int (*callback)(const uint8_t *data, size_t size)); +/* Using the weak attributed on LLVMFuzzerTestOneInput() breaks oss-fuzz but + on the other hand this is what Google needs to make LLVMFuzzerRunDriver() + work. Choose your poison Google! */ +/*__attribute__((weak))*/ int LLVMFuzzerTestOneInput(const uint8_t *Data, + size_t Size); +__attribute__((weak)) int LLVMFuzzerInitialize(int *argc, char ***argv); +__attribute__((weak)) int LLVMFuzzerRunDriver( + int *argc, char ***argv, int (*callback)(const uint8_t *data, size_t size)); // Default nop ASan hooks for manual poisoning when not linking the ASan // runtime @@ -101,10 +106,10 @@ __attribute__((weak)) void *__asan_region_is_poisoned(void *beg, size_t size); // Notify AFL about persistent mode. static volatile char AFL_PERSISTENT[] = "##SIG_AFL_PERSISTENT##"; +int __afl_persistent_loop(unsigned int); + // Notify AFL about deferred forkserver. static volatile char AFL_DEFER_FORKSVR[] = "##SIG_AFL_DEFER_FORKSRV##"; - -int __afl_persistent_loop(unsigned int); void __afl_manual_init(); // Use this optionally defined function to output sanitizer messages even if @@ -200,7 +205,8 @@ static void maybe_close_fd_mask() { // Define LLVMFuzzerMutate to avoid link failures for targets that use it // with libFuzzer's LLVMFuzzerCustomMutator. -size_t LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize) { +__attribute__((weak)) size_t LLVMFuzzerMutate(uint8_t *Data, size_t Size, + size_t MaxSize) { // assert(false && "LLVMFuzzerMutate should not be called from afl_driver"); return 0; @@ -262,6 +268,17 @@ static int ExecuteFilesOnyByOne(int argc, char **argv, __attribute__((weak)) int main(int argc, char **argv) { + // Enable if LLVMFuzzerTestOneInput() has the weak attribute + /* + if (!LLVMFuzzerTestOneInput) { + + fprintf(stderr, "Error: function LLVMFuzzerTestOneInput() not found!\n"); + abort(); + + } + + */ + if (argc < 2 || strncmp(argv[1], "-h", 2) == 0) printf( "============================== INFO ================================\n" @@ -284,8 +301,9 @@ __attribute__((weak)) int main(int argc, char **argv) { } -int LLVMFuzzerRunDriver(int *argcp, char ***argvp, - int (*callback)(const uint8_t *data, size_t size)) { +__attribute__((weak)) int LLVMFuzzerRunDriver( + int *argcp, char ***argvp, + int (*callback)(const uint8_t *data, size_t size)) { int argc = *argcp; char **argv = *argvp; @@ -410,3 +428,9 @@ int LLVMFuzzerRunDriver(int *argcp, char ***argvp, } +#ifdef __cplusplus + +} + +#endif + diff --git a/utils/libtokencap/libtokencap.so.c b/utils/libtokencap/libtokencap.so.c index 299056ab..b21f3068 100644 --- a/utils/libtokencap/libtokencap.so.c +++ b/utils/libtokencap/libtokencap.so.c @@ -81,7 +81,11 @@ void *(*__libc_memmem)(const void *haystack, size_t haystack_len, #define MAX_MAPPINGS 1024 -static struct mapping { void *st, *en; } __tokencap_ro[MAX_MAPPINGS]; +static struct mapping { + + void *st, *en; + +} __tokencap_ro[MAX_MAPPINGS]; static u32 __tokencap_ro_cnt; static u8 __tokencap_ro_loaded; diff --git a/utils/socket_fuzzing/socketfuzz.c b/utils/socket_fuzzing/socketfuzz.c index 3ec8383b..7497519e 100644 --- a/utils/socket_fuzzing/socketfuzz.c +++ b/utils/socket_fuzzing/socketfuzz.c @@ -23,7 +23,8 @@ #include <errno.h> #include <stdio.h> #include <poll.h> -//#include "logging.h" // switche from preeny_info() to fprintf(stderr, "Info: " +// #include "logging.h" // switched from preeny_info() to fprintf(stderr, "Info: +// " // // originals diff --git a/utils/target_intelligence/README.md b/utils/target_intelligence/README.md new file mode 100644 index 00000000..086c9e20 --- /dev/null +++ b/utils/target_intelligence/README.md @@ -0,0 +1,61 @@ +# Target Intelligence + +These are some ideas you can do so that your target that you are fuzzing can +give helpful feedback to AFL++. + +## Add to the AFL++ dictionary from your target + +For this you target must be compiled for CMPLOG (`AFL_LLVM_CMPLOG=1`). + +Add in your source code: + +``` +__attribute__((weak)) void __cmplog_rtn_hook_strn(u8 *ptr1, u8 *ptr2, u64 len); +__attribute__((weak)) void __cmplog_ins_hook1(uint8_t arg1, uint8_t arg2, uint8_t attr); +__attribute__((weak)) void __cmplog_ins_hook2(uint16_t arg1, uint16_t arg2, uint8_t attr); +__attribute__((weak)) void __cmplog_ins_hook4(uint32_t arg1, uint32_t arg2, uint8_t attr); +__attribute__((weak)) void __cmplog_ins_hook8(uint64_t arg1, uint64_t arg2, uint8_t attr); + +int in_your_function(...) { + + // to add two strings to the AFL++ dictionary: + if (__cmplog_rtn_hook_strn) + __cmplog_rtn_hook_strn(string1, length_of_string1, string2, length_of_string2); + + // to add two 32 bit integers to the AFL++ dictionary: + if (__cmplog_ins_hook4) + __cmplog_ins_hook4(first_32_bit_var, second_32_bit_var, 0); + +} +``` + +Note that this only makes sense if these values are in-depth processed in the +target in a way that AFL++ CMPLOG cannot uncover these, e.g. if these values +are transformed by a matrix computation. + +Fixed values are always better to give to afl-fuzz via a `-x dictionary`. + +## Add inputs to AFL++ dictionary from your target + +If for whatever reason you want your target to propose new inputs to AFL++, +then this is actually very easy. +The environment variable `AFL_CUSTOM_INFO_OUT` contains the output directory +of this run - including the fuzzer instance name (e.g. `default`), so if you +run `afl-fuzz -o out -S foobar`, the value would be `out/foobar`). + +To show afl-fuzz an input it should consider just do the following: + +1. create the directory `$AFL_CUSTOM_INFO_OUT/../target/queue` +2. create any new inputs you want afl-fuzz to notice in that directory with the + following naming convention: `id:NUMBER-OF-LENGTH-SIX-WITH-LEADING-ZEROES,whatever` + where that number has to be increasing. + e.g.: +``` + id:000000,first_file + id:000001,second_file + id:000002,third_file + etc. +``` + +Note that this will not work in nyx_mode because afl-fuzz cannot see inside the +virtual machine. |