From b51a2ac72a3cbd1b470890d0151a46da28e6754e Mon Sep 17 00:00:00 2001
From: Ivan Nardi <12729895+IvanNardi@users.noreply.github.com>
Date: Thu, 9 Feb 2023 20:02:12 +0100
Subject: fuzz: some improvements and add two new fuzzers (#1881)

Remove `FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION` define from
`fuzz/Makefile.am`; it is already included by the main configure script
(when fuzzing).

Add a knob to force disabling of AESNI optimizations: this way we can
fuzz also no-aesni crypto code.

Move CRC32 algorithm into the library.

Add some fake traces to extend fuzzing coverage. Note that these traces
are hand-made (via scapy/curl) and must not be used as "proof" that the
dissectors are really able to identify this kind of traffic.

Some small updates to some dissectors:

CSGO: remove a wrong rule (never triggered, BTW). Any UDP packet starting
with "VS01" will be classified as STEAM (see steam.c around line 111).
Googling it, it seems right so.

XBOX: XBOX only analyses UDP flows while HTTP only TCP ones; therefore
that condition is false.

RTP, STUN: removed useless "break"s

Zattoo: `flow->zattoo_stage` is never set to any values greater or equal
to 5, so these checks are never true.

PPStream: `flow->l4.udp.ppstream_stage` is never read. Delete it.

TeamSpeak: we check for `flow->packet_counter == 3` just above, so the
following check `flow->packet_counter >= 3` is always false.
---
 src/lib/third_party/src/gcrypt/aesni.c | 9 +++++++++
 src/lib/third_party/src/hll/hll.c      | 4 ----
 2 files changed, 9 insertions(+), 4 deletions(-)

(limited to 'src/lib/third_party')

diff --git a/src/lib/third_party/src/gcrypt/aesni.c b/src/lib/third_party/src/gcrypt/aesni.c
index b47fb6ba6..d1379de6f 100644
--- a/src/lib/third_party/src/gcrypt/aesni.c
+++ b/src/lib/third_party/src/gcrypt/aesni.c
@@ -49,6 +49,10 @@
 static u_int8_t cached_has_aesni = 0, has_aesni_checked = 0;
 #endif
 
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+int force_no_aesni = 0;
+#endif
+
 /*
  * AES-NI support detection routine
  */
@@ -60,6 +64,11 @@ int mbedtls_aesni_has_support( unsigned int what )
 #  endif
 #endif
 
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+  if(force_no_aesni == 1)
+    return 0;
+#endif
+
 #if defined(linux) || defined(__linux__)
   if(has_aesni_checked == 0) {
     /*
diff --git a/src/lib/third_party/src/hll/hll.c b/src/lib/third_party/src/hll/hll.c
index b0e0a1343..344971b61 100644
--- a/src/lib/third_party/src/hll/hll.c
+++ b/src/lib/third_party/src/hll/hll.c
@@ -30,10 +30,6 @@
 #include "../include/MurmurHash3.h"
 #include "../include/hll.h"
 
-u_int32_t _hll_hash(const struct ndpi_hll *hll) {
-  return MurmurHash3_x86_32(hll->registers, (u_int32_t)hll->size, 0);
-}
-
 /* Count the number of leading zero's */
 static __inline u_int8_t _hll_rank(u_int32_t hash, u_int8_t bits) {
   u_int8_t i;
-- 
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