Add filter logging.

src/common/config.h

@@ -20,4 +20,8 @@
 // If uncommented, rate limits for clients are determined using the source IP, port, and protocol instead of just the source IP.
 // This allows for more precise rate limits (connection-specific instead of a single source IP).
 // I decided not to include the destination IP/port because the source IP, port, and protocol should be represent a unique connection.
-#define USE_FLOW_RL
+#define USE_FLOW_RL
+
+// Enables filter logging through XDP.
+// If performance is a concerned, it is best to disable this feature by commenting out the below line with //.
+#define ENABLE_FILTER_LOGGING

src/common/types.h

@@ -64,6 +64,8 @@ struct filter
 {
     u8 id;
 
+    unsigned int log : 1;
+
     unsigned int enabled : 1;
 
     u8 action;
@@ -131,4 +133,15 @@ struct flow6
     u128 ip;
     u16 port;
     u8 protocol;
-} typedef flow6_t;
+} typedef flow6_t;
+
+struct filter_log_event
+{
+    u64 ts;
+    int filter_id;
+    u32 src_ip;
+    u32 src_ip6[4];
+    u16 src_port;
+    u64 pps;
+    u64 bps;
+} typedef filter_log_event_t;