diff --git a/SourceCode/arduino/lib/Firewall/Firewall.cpp b/SourceCode/arduino/lib/Firewall/Firewall.cpp
index 06d482c..281d1c8 100644
--- a/SourceCode/arduino/lib/Firewall/Firewall.cpp
+++ b/SourceCode/arduino/lib/Firewall/Firewall.cpp
@@ -7,19 +7,13 @@ ESPFirewall::ESPFirewall(int port)
     this->setup_routing();
 }
 
-void ESPFirewall::add_rule_to_firewall(const char *source, const char *destination, const char *protocol, const char *target)
+void ESPFirewall::add_rule_to_firewall(firewall_rule_t *rule)
 {
     firewall_rule_t *temp;
-    firewall_rule_t *link = (firewall_rule_t *)malloc(sizeof(firewall_rule_t));
-    link->key = ++amount_of_rules;
-    strcpy(link->source, source);
-    strcpy(link->destination, destination);
-    strcpy(link->protocol, protocol);
-    strcpy(link->target, target);
     if (head == NULL)
     {
-        head = link;
-        link->next = NULL;
+        head = rule;
+        rule->next = NULL;
         return;
     }
     temp = head;
@@ -27,8 +21,8 @@ void ESPFirewall::add_rule_to_firewall(const char *source, const char *destinati
     {
         temp = temp->next;
     }
-    temp->next = link;
-    link->next = NULL;
+    temp->next = rule;
+    rule->next = NULL;
     return;
 }
 
@@ -58,17 +52,30 @@ void ESPFirewall::post_firewall_handler(AsyncWebServerRequest *request)
     DynamicJsonDocument json(1024);
     String response;
     int response_code;
-    if (request->hasArg("source") || request->hasArg("destination") || request->hasArg("protocol") || request->hasArg("target"))
+    if (request_has_firewall_parameter(request))
     {
+        firewall_rule_t *rule = (firewall_rule_t *)malloc(sizeof(firewall_rule_t));
+        rule->key = ++amount_of_rules;
+
         const char *source = request->arg("source").c_str();
+        strcpy(rule->source, strlen(source) <= IP4ADDR_STRLEN_MAX ? source : "-");
+
         const char *destination = request->arg("destination").c_str();
+        strcpy(rule->destination, strlen(destination) <= IP4ADDR_STRLEN_MAX ? destination : "-");
+
         const char *protocol = request->arg("protocol").c_str();
+        strcpy(rule->protocol, strlen(protocol) <= PROTOCOL_LENGTH ? protocol : "-");
+
         const char *target = request->arg("target").c_str();
-        json["source"] = source;
-        json["destination"] = destination;
-        json["protocol"] = protocol;
-        json["target"] = target;
-        add_rule_to_firewall(source, destination, protocol, target);
+        strcpy(rule->target, strlen(target) <= TARGET_LENGTH ? target : "-");
+
+        add_rule_to_firewall(rule);
+
+        json["key"] = rule->key;
+        json["source"] = rule->source;
+        json["destination"] = rule->destination;
+        json["protocol"] = rule->protocol;
+        json["target"] = rule->target;
         response_code = 200;
     }
     else
@@ -89,6 +96,11 @@ void ESPFirewall::not_found(AsyncWebServerRequest *request)
     request->send(404, "application/json", response);
 }
 
+bool ESPFirewall::request_has_firewall_parameter(AsyncWebServerRequest *request)
+{
+    return request->hasArg("source") || request->hasArg("destination") || request->hasArg("protocol") || request->hasArg("target");
+}
+
 void ESPFirewall::setup_routing()
 {
     firewall_api->on("/api/v1/firewall", HTTP_GET, std::bind(&ESPFirewall::get_firewall_handler, this, std::placeholders::_1));
diff --git a/SourceCode/arduino/lib/Firewall/Firewall.h b/SourceCode/arduino/lib/Firewall/Firewall.h
index 662d601..77c916d 100644
--- a/SourceCode/arduino/lib/Firewall/Firewall.h
+++ b/SourceCode/arduino/lib/Firewall/Firewall.h
@@ -13,13 +13,16 @@
 #endif
 #include "ESPAsyncWebServer.h"
 
+#define PROTOCOL_LENGTH 4
+#define TARGET_LENGTH 7
+
 typedef struct firewall_rule
 {
     int key;
     char source[IP4ADDR_STRLEN_MAX];
     char destination[IP4ADDR_STRLEN_MAX];
-    char protocol[4];
-    char target[7];
+    char protocol[PROTOCOL_LENGTH];
+    char target[TARGET_LENGTH];
     struct firewall_rule *next;
 } firewall_rule_t;
 
@@ -29,10 +32,11 @@ class ESPFirewall
     unsigned int amount_of_rules = 0;
     struct firewall_rule *head = NULL;
 
-    void add_rule_to_firewall(const char *source, const char *destination, const char *protocol, const char *target);
+    void add_rule_to_firewall(firewall_rule_t *rule);
     void get_firewall_handler(AsyncWebServerRequest *request);
     void post_firewall_handler(AsyncWebServerRequest *request);
     void not_found(AsyncWebServerRequest *request);
+    bool request_has_firewall_parameter(AsyncWebServerRequest *request);
     void setup_routing();
 
 public: