Zlib ng

libs/zlibng/test/fuzz/checksum_fuzzer.c

@@ -0,0 +1,73 @@
+#include <stdio.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <inttypes.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;
+  /* 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[32];
+
+  /* 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 */
+  PREFIX(crc32_combine_gen)(op, 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);
+  }
+  crc1 = PREFIX(crc32_z)(crc1, data + offset, dataLen % buffSize);
+
+  crc2 = PREFIX(crc32_z)(crc2, data, dataLen);
+
+  assert(crc1 == crc2);
+  assert(PREFIX(crc32_combine)(crc1, crc2, dataLen) ==
+         PREFIX(crc32_combine)(crc1, crc1, dataLen));
+
+  /* Fast CRC32 combine. */
+  PREFIX(crc32_combine_gen)(op, dataLen);
+  assert(PREFIX(crc32_combine_op)(crc1, crc2, op) ==
+         PREFIX(crc32_combine_op)(crc2, crc1, op));
+  assert(PREFIX(crc32_combine)(crc1, crc2, dataLen) ==
+         PREFIX(crc32_combine_op)(crc2, crc1, op));
+
+  /* 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);
+  assert(PREFIX(adler32_combine)(adler1, adler2, dataLen) ==
+         PREFIX(adler32_combine)(adler1, adler1, dataLen));
+
+  /* This function must return 0. */
+  return 0;
+}