examples: add flow callbacks to rust plugin example

Ticket: #8446

examples/plugins/rust/src/mod.rs

@@ -1,26 +1,43 @@
 use std::ptr::null_mut;
 
-use suricata_ffi::eve::{self, Flow, Packet, SCJsonBuilder, ThreadVars};
+use suricata_ffi::eve::{self, SCJsonBuilder};
+use suricata_ffi::flow;
 use suricata_ffi::jsonbuilder::JsonBuilder;
 use suricata_ffi::{SCLogError, SCLogNotice};
-use suricata_sys::sys::{SCEveRegisterCallback, SCPlugin};
+use suricata_sys::sys::{Flow, Packet, SCEveRegisterCallback, SCPlugin, ThreadVars};
 
 unsafe extern "C" fn init() {
     suricata_ffi::plugin::init();
     SCLogNotice!("Initializing rust example plugin");
 
-    if let Err(err) = register() {
-        SCLogError!("Failed to register rust example EVE callback: {}", err);
+    if let Err(err) = register_eve_callbacks() {
+        SCLogError!("Failed to register rust example EVE callbacks: {}", err);
+    }
+    if let Err(err) = register_flow_callbacks() {
+        SCLogError!("Failed to register rust example flow callbacks: {}", err);
     }
 }
 
 pub fn register() -> Result<(), &'static str> {
+    register_eve_callbacks()?;
+    register_flow_callbacks()?;
+    Ok(())
+}
+
+pub fn register_eve_callbacks() -> Result<(), &'static str> {
     if !unsafe { SCEveRegisterCallback(Some(log_eve_raw), null_mut()) } {
         return Err("Failed to register raw EVE callback");
     }
     eve::register_callback(log_eve_wrapped)
 }
 
+pub fn register_flow_callbacks() -> Result<(), &'static str> {
+    flow::register_init_callback(log_flow_init)?;
+    flow::register_update_callback(log_flow_update)?;
+    flow::register_finish_callback(log_flow_finish)?;
+    Ok(())
+}
+
 unsafe extern "C" fn log_eve_raw(
     _tv: *mut ThreadVars,
     _p: *const Packet,
@@ -47,6 +64,22 @@ fn log_eve_wrapped(
     Ok(())
 }
 
+fn log_flow_init(_tv: *mut ThreadVars, _f: *mut Flow, _p: *const Packet) {
+    SCLogNotice!("rust example flow init callback: flow={:p}", _f);
+}
+
+fn log_flow_update(_tv: *mut ThreadVars, _f: *mut Flow, _p: *mut Packet) {
+    SCLogNotice!(
+        "rust example flow update callback: flow={:p}, packet={:p}",
+        _f,
+        _p
+    );
+}
+
+fn log_flow_finish(_tv: *mut ThreadVars, _f: *mut Flow) {
+    SCLogNotice!("rust example flow finish callback: flow={:p}", _f);
+}
+
 #[no_mangle]
 extern "C" fn SCPluginRegister() -> *mut SCPlugin {
     suricata_ffi::plugin::Plugin {