diff --git a/src/openvpn/manage.c b/src/openvpn/manage.c
index 685b137c..e46b5f22 100644
--- a/src/openvpn/manage.c
+++ b/src/openvpn/manage.c
@@ -608,14 +608,14 @@ man_kill(struct management *man, const char *victim)
             if (status)
             {
                 const int port = atoi(p3);
-                const int proto = (streq(p1, "tcp"))   ? PROTO_TCP_SERVER
-                                  : (streq(p1, "udp")) ? PROTO_UDP
-                                                       : PROTO_NONE;
+                const uint8_t proto = (streq(p1, "tcp"))   ? PROTO_TCP_SERVER
+                                      : (streq(p1, "udp")) ? PROTO_UDP
+                                                           : PROTO_NONE;
 
-                if ((port > 0 && port < 65536) && (proto != PROTO_NONE))
+                if ((port > 0 && port < UINT16_MAX) && (proto != PROTO_NONE))
                 {
                     n_killed = (*man->persist.callback.kill_by_addr)(man->persist.callback.arg,
-                                                                     addr, port, proto);
+                                                                     addr, (uint16_t)port, proto);
                     if (n_killed > 0)
                     {
                         msg(M_CLIENT, "SUCCESS: %d client(s) at address %s:%s:%d killed", n_killed,
diff --git a/src/openvpn/manage.h b/src/openvpn/manage.h
index fe460bfb..dedcc155 100644
--- a/src/openvpn/manage.h
+++ b/src/openvpn/manage.h
@@ -178,7 +178,7 @@ struct management_callback
     void (*status)(void *arg, const int version, struct status_output *so);
     void (*show_net)(void *arg, const msglvl_t msglevel);
     int (*kill_by_cn)(void *arg, const char *common_name);
-    int (*kill_by_addr)(void *arg, const in_addr_t addr, const int port, const int proto);
+    int (*kill_by_addr)(void *arg, const in_addr_t addr, const uint16_t port, const uint8_t proto);
     void (*delete_event)(void *arg, event_t event);
     int (*n_clients)(void *arg);
     bool (*send_cc_message)(void *arg, const char *message, const char *parameter);
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index e2438432..261209d0 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -3937,7 +3937,7 @@ management_callback_kill_by_cn(void *arg, const char *del_cn)
 }
 
 static int
-management_callback_kill_by_addr(void *arg, const in_addr_t addr, const int port, const int proto)
+management_callback_kill_by_addr(void *arg, const in_addr_t addr, const uint16_t port, const uint8_t proto)
 {
     struct multi_context *m = (struct multi_context *)arg;
     struct hash_iterator hi;
diff --git a/src/openvpn/socket.h b/src/openvpn/socket.h
index e986c9cf..832d62e2 100644
--- a/src/openvpn/socket.h
+++ b/src/openvpn/socket.h
@@ -89,7 +89,7 @@ struct link_socket_info
     const char *ipchange_command;
     const struct plugin_list *plugins;
     bool remote_float;
-    int proto;       /* Protocol (PROTO_x defined below) */
+    uint8_t proto;   /* Protocol (PROTO_x defined below) */
     sa_family_t af;  /* Address family like AF_INET, AF_INET6 or AF_UNSPEC*/
     bool bind_ipv6_only;
     int mtu_changed; /* Set to true when mtu value is changed */