[fuzz] Add LZ4 frame fuzzers

* Round trip fuzzer
* Compress fuzzer
* Decompress fuzzer

1 files changed, 51 insertions, 0 deletions

diff --git a/ossfuzz/lz4_helpers.c b/ossfuzz/lz4_helpers.c
new file mode 100644
index 0000000..9471630
--- /dev/null
+++ b/ossfuzz/lz4_helpers.c
@@ -0,0 +1,51 @@
+#include "fuzz_helpers.h"
+#include "lz4_helpers.h"
+#include "lz4hc.h"
+
+LZ4F_frameInfo_t FUZZ_randomFrameInfo(uint32_t* seed)
+{
+    LZ4F_frameInfo_t info = LZ4F_INIT_FRAMEINFO;
+    info.blockSizeID = FUZZ_rand32(seed, LZ4F_max64KB - 1, LZ4F_max4MB);
+    if (info.blockSizeID < LZ4F_max64KB) {
+        info.blockSizeID = LZ4F_default;
+    }
+    info.blockMode = FUZZ_rand32(seed, LZ4F_blockLinked, LZ4F_blockIndependent);
+    info.contentChecksumFlag = FUZZ_rand32(seed, LZ4F_noContentChecksum,
+                                           LZ4F_contentChecksumEnabled);
+    info.blockChecksumFlag = FUZZ_rand32(seed, LZ4F_noBlockChecksum,
+                                         LZ4F_blockChecksumEnabled);
+    return info;
+}
+
+LZ4F_preferences_t FUZZ_randomPreferences(uint32_t* seed)
+{
+    LZ4F_preferences_t prefs = LZ4F_INIT_PREFERENCES;
+    prefs.frameInfo = FUZZ_randomFrameInfo(seed);
+    prefs.compressionLevel = FUZZ_rand32(seed, 0, LZ4HC_CLEVEL_MAX + 3) - 3;
+    prefs.autoFlush = FUZZ_rand32(seed, 0, 1);
+    prefs.favorDecSpeed = FUZZ_rand32(seed, 0, 1);
+    return prefs;
+}
+
+size_t FUZZ_decompressFrame(void* dst, const size_t dstCapacity,
+                            const void* src, const size_t srcSize)
+{
+    LZ4F_decompressOptions_t opts;
+    memset(&opts, 0, sizeof(opts));
+    opts.stableDst = 1;
+    LZ4F_dctx* dctx;
+    LZ4F_createDecompressionContext(&dctx, LZ4F_VERSION);
+    FUZZ_ASSERT(dctx);
+
+    size_t dstSize = dstCapacity;
+    size_t srcConsumed = srcSize;
+    size_t const rc =
+            LZ4F_decompress(dctx, dst, &dstSize, src, &srcConsumed, &opts);
+    FUZZ_ASSERT(!LZ4F_isError(rc));
+    FUZZ_ASSERT(rc == 0);
+    FUZZ_ASSERT(srcConsumed == srcSize);
+
+    LZ4F_freeDecompressionContext(dctx);
+
+    return dstSize;
+}