Merge pull request #462 from AFLplusplus/dev

Dev

.gitignore

@@ -5,6 +5,11 @@
 *.so
 *.pyc
 *.dSYM
+as
+ld
+in
+out
+core*
 afl-analyze
 afl-as
 afl-clang
@@ -43,13 +48,10 @@ afl-system-config.8
 afl-tmin.8
 afl-whatsup.8
 qemu_mode/libcompcov/compcovtest
-as
-ld
 qemu_mode/qemu-*
 unicorn_mode/samples/*/\.test-*
 unicorn_mode/samples/*/output/
 unicorn_mode/unicornafl
-core\.*
 test/unittests/unit_maybe_alloc
 test/unittests/unit_preallocable
 test/unittests/unit_list
@@ -57,5 +59,7 @@ test/unittests/unit_rand
 test/unittests/unit_hash
 examples/afl_network_proxy/afl-network-server
 examples/afl_network_proxy/afl-network-client
-in
-out
+examples/afl_frida/afl-frida
+examples/afl_frida/libtestinstr.so
+examples/afl_frida/frida-gum-example.c
+examples/afl_frida/frida-gum.h

README.md

@@ -357,9 +357,10 @@ Here are some good writeups to show how to effectively use AFL++:
  * [https://securitylab.github.com/research/fuzzing-sockets-FTP](https://securitylab.github.com/research/fuzzing-sockets-FTP)
 
 If you are interested in fuzzing structured data (where you define what the
-structure is), these two links have you covered:
- * [https://github.com/bruce30262/libprotobuf-mutator_fuzzing_learning/tree/master/4_libprotobuf_aflpp_custom_mutator](https://github.com/bruce30262/libprotobuf-mutator_fuzzing_learning/tree/master/4_libprotobuf_aflpp_custom_mutator)
- * [https://github.com/thebabush/afl-libprotobuf-mutator](https://github.com/thebabush/afl-libprotobuf-mutator)
+structure is), these links have you covered:
+ * Superion for afl++: [https://github.com/adrian-rt/superion-mutator](https://github.com/adrian-rt/superion-mutator)
+ * libprotobuf raw: [https://github.com/bruce30262/libprotobuf-mutator_fuzzing_learning/tree/master/4_libprotobuf_aflpp_custom_mutator](https://github.com/bruce30262/libprotobuf-mutator_fuzzing_learning/tree/master/4_libprotobuf_aflpp_custom_mutator)
+ * libprotobuf for old afl++ API: [https://github.com/thebabush/afl-libprotobuf-mutator](https://github.com/thebabush/afl-libprotobuf-mutator)
 
 If you find other good ones, please send them to us :-)
 

TODO.md

@@ -1,7 +1,8 @@
 # TODO list for AFL++
 
-## Roadmap 2.66+
+## Roadmap 2.67+
 
+ - allow to sync against honggfuzz and libfuzzer
  - AFL_MAP_SIZE for qemu_mode and unicorn_mode
  - namespace for targets? e.g. network
  - learn from honggfuzz (mutations, maybe ptrace?)

custom_mutators/README.md

@@ -10,3 +10,22 @@ Use with e.g.
 and add `AFL_CUSTOM_MUTATOR_ONLY=1` if you only want to use the custom mutator.
 
 Multiple custom mutators can be used by separating their paths with `:` in the environment variable.
+
+# Other custom mutators
+
+## Superion port
+
+Adrian Tiron ported the Superion grammar fuzzer to afl++, it is WIP and
+requires cmake (among other things):
+[https://github.com/adrian-rt/superion-mutator](https://github.com/adrian-rt/superion-mutator)
+
+## Protobuf
+
+There are two WIP protobuf projects, that require work to be working though:
+
+transforms protobuf raw:
+https://github.com/bruce30262/libprotobuf-mutator_fuzzing_learning/tree/master/4_libprotobuf_aflpp_custom_mutator
+
+has a transform function you need to fill for your protobuf format, however
+needs to be ported to the updated afl++ custom mutator API (not much work):
+https://github.com/thebabush/afl-libprotobuf-mutator

docs/custom_mutators.md

@@ -36,7 +36,7 @@ size_t afl_custom_fuzz(void *data, uint8_t *buf, size_t buf_size, u8 **out_buf,
 size_t afl_custom_post_process(void *data, uint8_t *buf, size_t buf_size, uint8_t **out_buf);
 int32_t afl_custom_init_trim(void *data, uint8_t *buf, size_t buf_size);
 size_t afl_custom_trim(void *data, uint8_t **out_buf);
-int32_t afl_custom_post_trim(void *data, int success) {
+int32_t afl_custom_post_trim(void *data, int success);
 size_t afl_custom_havoc_mutation(void *data, u8 *buf, size_t buf_size, u8 **out_buf, size_t max_size);
 uint8_t afl_custom_havoc_mutation_probability(void *data);
 uint8_t afl_custom_queue_get(void *data, const uint8_t *filename);

examples/afl_frida/README.md

@@ -31,4 +31,4 @@ However the stability is low. Reason is currently unknown.
 
 # Background
 
-This code ist copied for a larger part from https://github.com/meme/hotwax 
+This code is copied for a larger part from https://github.com/meme/hotwax

llvm_mode/README.lto.md

@@ -125,10 +125,9 @@ NOTE: some targets also need to set the linker, try both `afl-clang-lto` and
 
 ## AUTODICTIONARY feature
 
-Setting `AFL_LLVM_LTO_AUTODICTIONARY` will generate a dictionary in the
-target binary based on string compare and memory compare functions.
-afl-fuzz will automatically get these transmitted when starting to fuzz.
-This improves coverage on a lot of targets.
+While compiling, automatically a dictionary based on string comparisons is
+generated put into the target binary. This dictionary is transfered to afl-fuzz
+on start. This improves coverage statistically by 5-10% :)
 
 ## Fixed memory map
 
@@ -147,6 +146,8 @@ Some targets are difficult because the configure script does unusual stuff that
 is unexpected for afl. See the next chapter `Potential issues` how to solve
 these.
 
+### Example: ffmpeg
+
 An example of a hard to solve target is ffmpeg. Here is how to successfully
 instrument it:
 
@@ -186,6 +187,31 @@ instrument it:
 
 4. Then type make, wait for a long time and you are done :)
 
+### Example: WebKit jsc
+
+Building jsc is difficult as the build script has bugs.
+
+1. checkout Webkit: 
+```
+svn checkout https://svn.webkit.org/repository/webkit/trunk WebKit
+cd WebKit
+```
+
+2. Fix the build environment:
+```
+mkdir -p WebKitBuild/Release
+cd WebKitBuild/Release
+ln -s ../../../../../usr/bin/llvm-ar-11 llvm-ar-11
+ln -s ../../../../../usr/bin/llvm-ranlib-11 llvm-ranlib-11
+cd ../..
+```
+
+3. Build :)
+
+```
+Tools/Scripts/build-jsc --jsc-only --cli --cmakeargs="-DCMAKE_AR='llvm-ar-11' -DCMAKE_RANLIB='llvm-ranlib-11' -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON -DCMAKE_CC_FLAGS='-O3 -lrt' -DCMAKE_CXX_FLAGS='-O3 -lrt' -DIMPORTED_LOCATION='/lib/x86_64-linux-gnu/' -DCMAKE_CC=afl-clang-lto -DCMAKE_CXX=afl-clang-lto++ -DENABLE_STATIC_JSC=ON"
+```
+
 ## Potential issues
 
 ### compiling libraries fails

llvm_mode/afl-clang-fast.c

@@ -768,9 +768,19 @@ int main(int argc, char **argv, char **envp) {
 #if LLVM_VERSION_MAJOR <= 6
     instrument_mode = INSTRUMENT_AFL;
 #else
-    if (getenv("AFL_LLVM_INSTRUMENT_FILE") || getenv("AFL_LLVM_WHITELIST"))
+    if (getenv("AFL_LLVM_INSTRUMENT_FILE") || getenv("AFL_LLVM_WHITELIST")) {
+
       instrument_mode = INSTRUMENT_AFL;
-    else
+      WARNF(
+          "switching to classic instrumentation because "
+          "AFL_LLVM_INSTRUMENT_FILE does not work with PCGUARD. Use "
+          "-fsanitize-coverage-allowlist=allowlist.txt if you want to use "
+          "PCGUARD. See "
+          "https://clang.llvm.org/docs/"
+          "SanitizerCoverage.html#partially-disabling-instrumentation");
+
+    } else
+
       instrument_mode = INSTRUMENT_PCGUARD;
 #endif
 
@@ -818,9 +828,12 @@ int main(int argc, char **argv, char **envp) {
 
   if (instrument_mode == INSTRUMENT_PCGUARD &&
       (getenv("AFL_LLVM_INSTRUMENT_FILE") || getenv("AFL_LLVM_WHITELIST")))
-    WARNF(
+    FATAL(
         "Instrumentation type PCGUARD does not support "
-        "AFL_LLVM_INSTRUMENT_FILE!");
+        "AFL_LLVM_INSTRUMENT_FILE! Use "
+        "-fsanitize-coverage-allowlist=allowlist.txt instead, see "
+        "https://clang.llvm.org/docs/"
+        "SanitizerCoverage.html#partially-disabling-instrumentation");
 
   if (argc < 2 || strcmp(argv[1], "-h") == 0) {
 

src/afl-fuzz-mutators.c

@@ -286,6 +286,15 @@ u8 trim_case_custom(afl_state_t *afl, struct queue_entry *q, u8 *in_buf,
           "Trimmed data returned by custom mutator is larger than original "
           "data");
 
+    } else if (unlikely(retlen == 0)) {
+
+      /* Do not run the empty test case on the target. To keep the custom
+         trimming function running, we simply treat the empty test case as an
+         unsuccessful trimming and skip it, instead of aborting the trimming. */
+
+      ++afl->trim_execs;
+      goto unsuccessful_trimming;
+
     }
 
     write_to_testcase(afl, retbuf, retlen);
@@ -325,6 +334,8 @@ u8 trim_case_custom(afl_state_t *afl, struct queue_entry *q, u8 *in_buf,
 
     } else {
 
+    unsuccessful_trimming:
+
       /* Tell the custom mutator that the trimming was unsuccessful */
       afl->stage_cur = mutator->afl_custom_post_trim(mutator->data, 0);
       if (unlikely(afl->stage_cur < 0)) {

src/afl-fuzz.c

@@ -1048,6 +1048,12 @@ int main(int argc, char **argv_orig, char **envp) {
 
   }
 
+  #ifdef RAND_TEST_VALUES
+  u32 counter;
+  for (counter = 0; counter < 100000; counter++)
+    printf("DEBUG: rand %06d is %u\n", counter, rand_below(afl, 65536));
+  #endif
+
   setup_custom_mutators(afl);
 
   setup_cmdline_file(afl, argv + optind);