commit bc5b2a2e22b63f0f6f57cf067c3cdd23af785225
author David Benjamin <davidben@google.com> Tue Mar 01 22:57:32 2016 -0500
committer Adam Langley <agl@google.com> Thu Mar 03 01:36:19 2016 +0000
tree 0a34902a963b2a8a8e25559ee75421682567d212
parent 8b9e7802acde5e7d811ede05360b03fb4720e104

Add a deterministic PRNG for fuzzing.

If running the stack through a fuzzer, we would like execution to be
completely deterministic. This is gated on a
BORINGSSL_UNSAFE_FUZZER_MODE #ifdef.

For now, this just uses the zero ChaCha20 key and a global counter. As
needed, we can extend this to a thread-local counter and a separate
ChaCha20 stream and counter per input length.

Change-Id: Ic6c9d8a25e70d68e5dc6804e2c234faf48e51395
Reviewed-on: https://boringssl-review.googlesource.com/7286
Reviewed-by: Adam Langley <agl@google.com>

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8493559..bd1970c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -96,6 +96,8 @@
     message("You need to build with Clang for fuzzing to work")
   endif()
 
+  add_definitions(-DBORINGSSL_UNSAFE_FUZZER_MODE)
+
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fsanitize=address -fsanitize-coverage=edge,indirect-calls")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address -fsanitize-coverage=edge,indirect-calls")
   set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_C_FLAGS} -fsanitize=address")