udhcpinject: Multiple ssids sometime didn't display dhcp option 82 rules

Added check when parsing ssid info retrieved from iwinfo.
Program will exit if expected interface count and iwinfo entry count mismatch.

Fixes: WIFI-14564
Signed-off-by: alex18_huang <alex18_huang@accton.com>

feeds/ucentral/udhcpinject/files/etc/config/dhcpinject

@@ -5,3 +5,6 @@
 #   list ssid 'EAP101-ERICHI'
 #   list ssid 'EAP101-AKIHO'
 #   list ssid 'EAP101-DAMAYU'
+#
+# config dhcpinject 'dhcpinject'
+#   option iface_count '6'

feeds/ucentral/udhcpinject/files/etc/init.d/dhcpinject

@@ -9,9 +9,9 @@ SERVICE_NAME="dhcpinject"
 PROG=/usr/bin/udhcpinject
 
 start_service() {
-    local ssid_list=""
     local ssids=""
     local ports=""
+    local ifaces=""
 
     # Function to process each ssid
     append_ssid() {
@@ -40,6 +40,9 @@ start_service() {
 
     # Get the list of ports
     config_list_foreach uplink port append_port
+
+    # Get the iface_count
+    config_get ifaces dhcpinject iface_count
     
     # Fallback to eth0 if no ports are specified
     if [ -z "$ports" ]; then
@@ -47,11 +50,11 @@ start_service() {
     fi
 
     # Optional: Log or echo for debugging
-    logger -t dhcp_inject "Generated SSIDs=$ssids, Uplink=$ports"
+    logger -t dhcp_inject "Generated SSIDs=$ssids, Uplink=$ports, IFACEs=$ifaces"
 
     procd_open_instance "$SERVICE_NAME"
     procd_set_param command $PROG
-    procd_set_param env SSIDs="$ssids" PORTs="$ports"
+    procd_set_param env SSIDs="$ssids" PORTs="$ports" IFACEs="$ifaces"
     procd_set_param respawn 3600 10 10
     procd_set_param file /etc/config/dhcpinject
     procd_set_param reload_signal SIGHUP

feeds/ucentral/udhcpinject/src/udhcpinject.c

@@ -26,6 +26,7 @@ struct iface_info *iface_map = NULL;
 static struct port_info *ports = NULL;
 int iface_count = 0;
 int port_count = 0;
+int total_iface = 0;
 static pcap_t *handle = NULL;
 static char *provided_ssids = NULL;
 static char *provided_ports = NULL;
@@ -192,6 +193,11 @@ int parse_ssids(const char *ssids) {
         return -1;
     }
 
+    if (iface_count != total_iface) {
+        syslog(LOG_ERR, "Expect %d but only %d interfaces were found.\n", total_iface, iface_count);
+        return -1;
+    }
+
     syslog(LOG_INFO, "Found %d matching interfaces\n", iface_count);
     return 0;
 }
@@ -310,7 +316,6 @@ void signal_handler(int sig) {
         exit(0);
     } else if (sig == SIGHUP) {
         syslog(LOG_INFO, "Received reload signal, reconfiguring...\n");
-        sleep(5);
         // Clean up existing resources
         cleanup_tc();
         
@@ -561,7 +566,19 @@ int main(int argc, char *argv[]) {
     signal(SIGTERM, signal_handler);
     signal(SIGHUP, signal_handler);
 
-    sleep(5);
+    // Read IFACEs from environment variable
+    char *iface_env = getenv("IFACEs");
+    if (!iface_env) {
+        syslog(LOG_ERR, "No IFACEs provided. Exiting...\n");
+        cleanup();
+        return 1;
+    }
+    total_iface = atoi(iface_env);
+    if (total_iface <= 0) {
+        syslog(LOG_ERR, "Invalid IFACEs value: %s. Exiting...\n", iface_env);
+        cleanup();
+        return 1;
+    }
 
     provided_ssids = getenv("SSIDs");
     syslog(LOG_INFO, "Provided SSIDs: %s\n", provided_ssids);
@@ -618,4 +635,4 @@ int main(int argc, char *argv[]) {
 
     cleanup();
     return 0;
-}
+}