1 files changed, 81 insertions, 0 deletions
diff --git a/neozip/test/fuzz/fuzzer_checksum.c b/neozip/test/fuzz/fuzzer_checksum.c
new file mode 100644
index 0000000000..cedd284dbe
--- /dev/null
+++ b/neozip/test/fuzz/fuzzer_checksum.c
@@ -0,0 +1,81 @@
+#include <stdio.h>
+#include <assert.h>
+
+#include "zbuild.h"
+#ifdef ZLIB_COMPAT
+#  include "zlib.h"
+#else
+#  include "zlib-ng.h"
+#endif
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t dataLen) {
+    uint32_t crc0 = PREFIX(crc32)(0L, NULL, 0);
+    uint32_t crc1 = crc0;
+    uint32_t crc2 = crc0;
+    uint32_t adler0 = PREFIX(adler32)(0L, NULL, 0);
+    uint32_t adler1 = adler0;
+    uint32_t adler2 = adler0;
+    uint32_t combine1, combine2;
+    /* Checksum with a buffer of size equal to the first byte in the input. */
+    uint32_t buffSize = data[0];
+    uint32_t offset = 0;
+    uint32_t op;
+
+    /* Discard inputs larger than 1Mb. */
+    static size_t kMaxSize = 1024 * 1024;
+    if (dataLen < 1 || dataLen > kMaxSize)
+        return 0;
+
+    /* Make sure the buffer has at least a byte. */
+    if (buffSize == 0)
+        ++buffSize;
+
+    /* CRC32 */
+    op = PREFIX(crc32_combine_gen)(buffSize);
+    for (offset = 0; offset + buffSize <= dataLen; offset += buffSize) {
+        uint32_t crc3 = PREFIX(crc32_z)(crc0, data + offset, buffSize);
+        uint32_t crc4 = PREFIX(crc32_combine_op)(crc1, crc3, op);
+        crc1 = PREFIX(crc32_z)(crc1, data + offset, buffSize);
+        assert(crc1 == crc4);
+        Z_UNUSED(crc1);
+        Z_UNUSED(crc4);
+    }
+    crc1 = PREFIX(crc32_z)(crc1, data + offset, dataLen % buffSize);
+
+    crc2 = PREFIX(crc32_z)(crc2, data, dataLen);
+
+    assert(crc1 == crc2);
+    Z_UNUSED(crc1);
+    Z_UNUSED(crc2);
+    combine1 = PREFIX(crc32_combine)(crc1, crc2, (z_off_t)dataLen);
+    combine2 = PREFIX(crc32_combine)(crc1, crc1, (z_off_t)dataLen);
+    assert(combine1 == combine2);
+
+    /* Fast CRC32 combine. */
+    op = PREFIX(crc32_combine_gen)((z_off_t)dataLen);
+    combine1 = PREFIX(crc32_combine_op)(crc1, crc2, op);
+    combine2 = PREFIX(crc32_combine_op)(crc2, crc1, op);
+    assert(combine1 == combine2);
+    combine1 = PREFIX(crc32_combine)(crc1, crc2, (z_off_t)dataLen);
+    combine2 = PREFIX(crc32_combine_op)(crc2, crc1, op);
+    assert(combine1 == combine2);
+
+    /* Adler32 */
+    for (offset = 0; offset + buffSize <= dataLen; offset += buffSize)
+        adler1 = PREFIX(adler32_z)(adler1, data + offset, buffSize);
+    adler1 = PREFIX(adler32_z)(adler1, data + offset, dataLen % buffSize);
+
+    adler2 = PREFIX(adler32_z)(adler2, data, dataLen);
+
+    assert(adler1 == adler2);
+    Z_UNUSED(adler1);
+    Z_UNUSED(adler2);
+    combine1 = PREFIX(adler32_combine)(adler1, adler2, (z_off_t)dataLen);
+    combine2 = PREFIX(adler32_combine)(adler1, adler1, (z_off_t)dataLen);
+    assert(combine1 == combine2);
+    Z_UNUSED(combine1);
+    Z_UNUSED(combine2);
+
+    /* This function must return 0. */
+    return 0;
+}