Implement max_topic_levels configuration

rmqtt · Aug 25, 2023 · 69ac9a9 · 69ac9a9
1 parent 15a9496
commit 69ac9a9
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Showing 2 changed files with 9 additions and 0 deletions.
diff --git a/rmqtt/src/broker/error.rs b/rmqtt/src/broker/error.rs
@@ -51,6 +51,8 @@ pub enum MqttError {
     Utf8Error(#[from] Utf8Error),
     #[error("too many subscriptions")]
     TooManySubscriptions,
+    #[error("too many topic levels")]
+    TooManyTopicLevels,
     #[error("{0}")]
     ConfigError(#[from] ConfigError),
     #[error("{0}")]

diff --git a/rmqtt/src/broker/session.rs b/rmqtt/src/broker/session.rs
@@ -6,6 +6,7 @@ use std::fmt;
 use std::num::NonZeroU16;
 use std::ops::Deref;
 use std::rc::Rc;
+use std::str::FromStr;
 use std::sync::atomic::{AtomicBool, AtomicI64, Ordering};
 use std::sync::Arc;
 
@@ -637,6 +638,12 @@ impl SessionState {
             return Err(MqttError::TooManySubscriptions);
         }
 
+        if self.listen_cfg.max_topic_levels > 0
+            && Topic::from_str(&sub.topic_filter)?.len() > self.listen_cfg.max_topic_levels
+        {
+            return Err(MqttError::TooManyTopicLevels);
+        }
+
         sub.opts.set_qos(sub.opts.qos().less_value(self.listen_cfg.max_qos_allowed));
 
         //hook, client_subscribe