fuzz: improve coverage and remove dead code (#2135)

We are not able to remove custom rules: remove the empty stubs (which
originate from the original OpenDPI code).

`ndpi_guess_protocol_id()` is only called on the first packet of the
flow, so the bitmask `flow->excluded_protocol_bitmask` is always empty,
since we didn't call any dissectors yet.

Move another hash function to the dedicated source file.

1 files changed, 2 insertions, 32 deletions

diff --git a/src/lib/ndpi_utils.c b/src/lib/ndpi_utils.c
index 68c07fa6c..b41ec6706 100644
--- a/src/lib/ndpi_utils.c
+++ b/src/lib/ndpi_utils.c
@@ -2051,11 +2051,10 @@ const char* ndpi_risk2str(ndpi_risk_enum risk) {
 
   case NDPI_TLS_ALPN_SNI_MISMATCH:
     return("ALPN/SNI Mismatch");
-    
+
   case NDPI_MALWARE_HOST_CONTACTED:
     return("Client contacted a malware host");
-    break;
-    
+
   default:
     ndpi_snprintf(buf, sizeof(buf), "%d", (int)risk);
     return(buf);
@@ -2201,35 +2200,6 @@ ndpi_http_method ndpi_http_str2method(const char* method, u_int16_t method_len)
 
 /* ******************************************************************** */
 
-#define ROR64(x,r) (((x)>>(r))|((x)<<(64-(r))))
-
-/*
-  'in_16_bytes_long` points to some 16 byte memory data to be hashed;
-  two independent 64-bit linear congruential generators are applied
-  results are mixed, scrambled and cast to 32-bit
-*/
-u_int32_t ndpi_quick_16_byte_hash(u_int8_t *in_16_bytes_long) {
-  u_int64_t a = *(u_int64_t*)(in_16_bytes_long + 0);
-  u_int64_t c = *(u_int64_t*)(in_16_bytes_long + 8);
-
-  // multipliers are taken from sprng.org, addends are prime
-  a = a * 0x2c6fe96ee78b6955 + 0x9af64480a3486659;
-  c = c * 0x369dea0f31a53f85 + 0xd0c6225445b76b5b;
-
-  // mix results
-  a += c;
-
-  // final scramble
-  a ^= ROR64(a, 13) ^ ROR64(a, 7);
-
-  // down-casting, also taking advantage of upper half
-  a ^= a >> 32;
-
-  return((u_int32_t)a);
-}
-
-/* ******************************************************************** */
-
 int ndpi_hash_init(ndpi_str_hash **h)
 {
   if (h == NULL)