From 398d29064e770fbf1e79eec26542ec9fe9677fa4 Mon Sep 17 00:00:00 2001
From: Eric Severance <esev@esev.com>
Date: Fri, 20 Dec 2024 19:06:01 -0800
Subject: [PATCH] Separate host/port before checking for private IP (#5630)

---
 src/mqtt/MQTT.cpp | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/src/mqtt/MQTT.cpp b/src/mqtt/MQTT.cpp
index 7b15e99f3..c7db4672a 100644
--- a/src/mqtt/MQTT.cpp
+++ b/src/mqtt/MQTT.cpp
@@ -227,6 +227,16 @@ bool isPrivateIpAddress(const IPAddress &ip)
     }
     return false;
 }
+
+std::pair<std::string, uint16_t> parseHostAndPort(std::string address, uint16_t port = 0)
+{
+    const size_t delimIndex = address.find_first_of(':');
+    if (delimIndex > 0) {
+        port = std::stoul(address.substr(delimIndex + 1, address.length()));
+        address.resize(delimIndex);
+    }
+    return std::make_pair(std::move(address), port);
+}
 } // namespace
 
 void MQTT::mqttCallback(char *topic, byte *payload, unsigned int length)
@@ -302,7 +312,8 @@ MQTT::MQTT() : concurrency::OSThread("mqtt"), mqttQueue(MAX_MQTT_QUEUE)
         }
 
         IPAddress ip;
-        isMqttServerAddressPrivate = ip.fromString(moduleConfig.mqtt.address) && isPrivateIpAddress(ip);
+        isMqttServerAddressPrivate =
+            ip.fromString(parseHostAndPort(moduleConfig.mqtt.address).first.c_str()) && isPrivateIpAddress(ip);
 
 #if HAS_NETWORKING
         if (!moduleConfig.mqtt.proxy_to_client_enabled)
@@ -418,14 +429,9 @@ void MQTT::reconnect()
         pubSub.setClient(mqttClient);
 #endif
 
-        String server = String(serverAddr);
-        int delimIndex = server.indexOf(':');
-        if (delimIndex > 0) {
-            String port = server.substring(delimIndex + 1, server.length());
-            server[delimIndex] = 0;
-            serverPort = port.toInt();
-            serverAddr = server.c_str();
-        }
+        std::pair<std::string, uint16_t> hostAndPort = parseHostAndPort(serverAddr, serverPort);
+        serverAddr = hostAndPort.first.c_str();
+        serverPort = hostAndPort.second;
         pubSub.setServer(serverAddr, serverPort);
         pubSub.setBufferSize(512);