A new interface for dissectors registration (#2843)

We use `registr_dissector()` instead of
`ndpi_set_bitmask_protocol_detection()`.

Every file in `src/lib/protocols/*.c` is a dissector.

Every dissector can handle multiple protocols.

The real goal is this small change:
```
 struct call_function_struct {
-  NDPI_PROTOCOL_BITMASK detection_bitmask;
```
i.e. getting rid of another protocol bitmask: this is mandatory to try
to fix #2136 (see also e845e8205b68752c997d05224d8b2fd45acde714)

As a nice side effect, we remove a bitmask comparison in the hot function
`check_ndpi_detection_func()`

TODO: change logging configuration from per-protocol to per-dissector

1 files changed, 9 insertions, 13 deletions

diff --git a/src/lib/protocols/memcached.c b/src/lib/protocols/memcached.c
index 198735340..fcabbd0f7 100644
--- a/src/lib/protocols/memcached.c
+++ b/src/lib/protocols/memcached.c
@@ -112,7 +112,7 @@ static void ndpi_search_memcached(struct ndpi_detection_module_struct *ndpi_stru
 
   if (packet->tcp != NULL) {
     if (packet->payload_packet_len < MEMCACHED_MIN_LEN) {
-      NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+      NDPI_EXCLUDE_DISSECTOR(ndpi_struct, flow);
       return;
     }
 
@@ -120,13 +120,13 @@ static void ndpi_search_memcached(struct ndpi_detection_module_struct *ndpi_stru
   }
   else if (packet->udp != NULL) {
     if (packet->payload_packet_len < MEMCACHED_MIN_UDP_LEN) {
-      NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+      NDPI_EXCLUDE_DISSECTOR(ndpi_struct, flow);
       return;
     }
 
     if ((offset[4] == 0x00 && offset[5] == 0x00) ||
 	offset[6] != 0x00 || offset[7] != 0x00) {
-      NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+      NDPI_EXCLUDE_DISSECTOR(ndpi_struct, flow);
       return;
     }
 
@@ -170,17 +170,13 @@ static void ndpi_search_memcached(struct ndpi_detection_module_struct *ndpi_stru
   if (*matches >= MEMCACHED_MIN_MATCH)
     ndpi_int_memcached_add_connection(ndpi_struct, flow);
   else if(flow->packet_counter > 5)
-    NDPI_EXCLUDE_PROTO(ndpi_struct, flow);    
+    NDPI_EXCLUDE_DISSECTOR(ndpi_struct, flow);    
 }
 
-void init_memcached_dissector(
-			      struct ndpi_detection_module_struct *ndpi_struct)
+void init_memcached_dissector(struct ndpi_detection_module_struct *ndpi_struct)
 {
-  ndpi_set_bitmask_protocol_detection("MEMCACHED",
-				      ndpi_struct,
-				      NDPI_PROTOCOL_MEMCACHED,
-				      ndpi_search_memcached,
-				      NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_OR_UDP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
-				      SAVE_DETECTION_BITMASK_AS_UNKNOWN,
-				      ADD_TO_DETECTION_BITMASK);
+  register_dissector("MEMCACHED", ndpi_struct,
+                     ndpi_search_memcached,
+                     NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_OR_UDP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
+                      1, NDPI_PROTOCOL_MEMCACHED);
 }