Add some fuzzers to test other data structures. (#1870)

Start using a dictionary for fuzzing (see:
https://llvm.org/docs/LibFuzzer.html#dictionaries).
Remove some dead code.
Fuzzing with debug enabled is not usually a great idea (from performance
POV). Keep the code since it might be useful while debugging.

1 files changed, 58 insertions, 0 deletions

diff --git a/fuzz/fuzz_community_id.cpp b/fuzz/fuzz_community_id.cpp
new file mode 100644
index 000000000..3a029ec79
--- /dev/null
+++ b/fuzz/fuzz_community_id.cpp
@@ -0,0 +1,58 @@
+#include "ndpi_api.h"
+#include "fuzz_common_code.h"
+
+#include <stdint.h>
+#include <stdio.h>
+#include <assert.h>
+#include "fuzzer/FuzzedDataProvider.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+  FuzzedDataProvider fuzzed_data(data, size);
+  u_int8_t is_ipv6, l4_proto, icmp_type, icmp_code;
+  u_int16_t src_port, dst_port;
+  u_char *hash_buf;
+  u_int8_t hash_buf_len;
+
+  /* Just to have some data */
+
+  /* To allow memory allocation failures */
+  fuzz_set_alloc_callbacks_and_seed(size);
+
+  is_ipv6 = fuzzed_data.ConsumeBool();
+  l4_proto = fuzzed_data.ConsumeIntegral<u_int8_t>();
+  src_port = fuzzed_data.ConsumeIntegral<u_int16_t>();
+  dst_port = fuzzed_data.ConsumeIntegral<u_int16_t>();
+  icmp_type = fuzzed_data.ConsumeIntegral<u_int8_t>();
+  icmp_code = fuzzed_data.ConsumeIntegral<u_int8_t>();
+  hash_buf_len = fuzzed_data.ConsumeIntegralInRange(0, 64);
+  hash_buf = (u_char *)ndpi_malloc(hash_buf_len);
+  if (!hash_buf)
+    return 0;
+
+  if (!is_ipv6) {
+    u_int32_t src_ip, dst_ip;
+
+    src_ip = fuzzed_data.ConsumeIntegral<u_int32_t>();
+    dst_ip = fuzzed_data.ConsumeIntegral<u_int32_t>();
+
+    ndpi_flowv4_flow_hash(l4_proto, src_ip, dst_ip, src_port, dst_port,
+                          icmp_type, icmp_code, hash_buf, hash_buf_len);
+  } else {
+    u_char *src_ip, *dst_ip;
+
+    if(fuzzed_data.remaining_bytes() >= 32) {
+      std::vector<u_int8_t>data1 = fuzzed_data.ConsumeBytes<u_int8_t>(16);
+      src_ip = data1.data();
+      std::vector<u_int8_t>data2 = fuzzed_data.ConsumeBytes<u_int8_t>(16);
+      dst_ip = data2.data();
+
+      ndpi_flowv6_flow_hash(l4_proto, (struct ndpi_in6_addr *)src_ip,
+                            (struct ndpi_in6_addr *)dst_ip, src_port, dst_port,
+                            icmp_type, icmp_code, hash_buf, hash_buf_len);
+    }
+  }
+
+  ndpi_free(hash_buf);
+
+  return 0;
+}