diff --git a/s-ui.sh b/s-ui.sh
index 43e7563..550b3ae 100644
--- a/s-ui.sh
+++ b/s-ui.sh
@@ -1,4 +1,3 @@
-
 #!/bin/bash
 
 red='\033[0;31m'
@@ -6,7 +5,6 @@ green='\033[0;32m'
 yellow='\033[0;33m'
 plain='\033[0m'
 
-#Add some basic function here
 function LOGD() {
     echo -e "${yellow}[DEG] $* ${plain}"
 }
@@ -18,10 +16,9 @@ function LOGE() {
 function LOGI() {
     echo -e "${green}[INF] $* ${plain}"
 }
-# check root
+
 [[ $EUID -ne 0 ]] && LOGE "ERROR: You must be root to run this script! \n" && exit 1
 
-# Check OS and set release variable
 if [[ -f /etc/os-release ]]; then
     source /etc/os-release
     release=$ID
@@ -35,7 +32,6 @@ fi
 
 echo "The OS release is: $release"
 
-
 os_version=""
 os_version=$(grep -i version_id /etc/os-release | cut -d \" -f2 | cut -d . -f1)
 
@@ -54,8 +50,8 @@ elif [[ "${release}" == "centos" ]]; then
         echo -e "${red} Please use CentOS 8 or higher ${plain}\n" && exit 1
     fi
 elif [[ "${release}" == "ubuntu" ]]; then
-    if [[ ${os_version} -lt 20 ]]; then
-        echo -e "${red} Please use Ubuntu 20 or higher version!${plain}\n" && exit 1
+    if [[ ${os_version} -lt 22 ]]; then
+        echo -e "${red} Please use Ubuntu 22 or higher version!${plain}\n" && exit 1
     fi
 elif [[ "${release}" == "fedora" ]]; then
     if [[ ${os_version} -lt 36 ]]; then
@@ -80,7 +76,7 @@ elif [[ "${release}" == "oracle" ]]; then
 else
     echo -e "${red}Your operating system is not supported by this script.${plain}\n"
     echo "Please ensure you are using one of the following supported operating systems:"
-    echo "- Ubuntu 20.04+"
+    echo "- Ubuntu 22.04+"
     echo "- Debian 11+"
     echo "- CentOS 8+"
     echo "- Fedora 36+"
@@ -93,7 +89,6 @@ else
     echo "- Oracle Linux 8+"
     echo "- OpenSUSE Tumbleweed"
     exit 1
-
 fi
 
 confirm() {
@@ -164,7 +159,6 @@ custom_version() {
 
     download_link="https://raw.githubusercontent.com/alireza0/s-ui/master/install.sh"
 
-    # Use the entered panel version in the download link
     install_command="bash <(curl -Ls $download_link) $panel_version"
 
     echo "Downloading and installing panel version $panel_version..."
@@ -232,13 +226,11 @@ set_setting() {
     echo -e "Enter the ${yellow}panel path${plain} (leave blank for existing/default value):"
     read config_path
 
-    # Sub configuration
     echo -e "Enter the ${yellow}subscription port${plain} (leave blank for existing/default value):"
     read config_subPort
     echo -e "Enter the ${yellow}subscription path${plain} (leave blank for existing/default value):" 
     read config_subPath
 
-    # Set configs
     echo -e "${yellow}Initializing, please wait...${plain}"
     params=""
     [ -z "$config_port" ] || params="$params -port $config_port"
@@ -373,7 +365,6 @@ update_shell() {
     fi
 }
 
-# 0: running, 1: not running, 2: not installed
 check_status() {
     if [[ ! -f "/etc/systemd/system/$1.service" ]]; then
         return 2
@@ -487,20 +478,13 @@ bbr_menu() {
 }
 
 disable_bbr() {
-
     if ! grep -q "net.core.default_qdisc=fq" /etc/sysctl.conf || ! grep -q "net.ipv4.tcp_congestion_control=bbr" /etc/sysctl.conf; then
         echo -e "${yellow}BBR is not currently enabled.${plain}"
         exit 0
     fi
-
-    # Replace BBR with CUBIC configurations
     sed -i 's/net.core.default_qdisc=fq/net.core.default_qdisc=pfifo_fast/' /etc/sysctl.conf
     sed -i 's/net.ipv4.tcp_congestion_control=bbr/net.ipv4.tcp_congestion_control=cubic/' /etc/sysctl.conf
-
-    # Apply changes
     sysctl -p
-
-    # Verify that BBR is replaced with CUBIC
     if [[ $(sysctl net.ipv4.tcp_congestion_control | awk '{print $3}') == "cubic" ]]; then
         echo -e "${green}BBR has been replaced with CUBIC successfully.${plain}"
     else
@@ -513,8 +497,6 @@ enable_bbr() {
         echo -e "${green}BBR is already enabled!${plain}"
         exit 0
     fi
-
-    # Check the OS and install necessary packages
     case "${release}" in
     ubuntu | debian | armbian)
         apt-get update && apt-get install -yqq --no-install-recommends ca-certificates
@@ -533,15 +515,9 @@ enable_bbr() {
         exit 1
         ;;
     esac
-
-    # Enable BBR
     echo "net.core.default_qdisc=fq" | tee -a /etc/sysctl.conf
     echo "net.ipv4.tcp_congestion_control=bbr" | tee -a /etc/sysctl.conf
-
-    # Apply changes
     sysctl -p
-
-    # Verify that BBR is enabled
     if [[ $(sysctl net.ipv4.tcp_congestion_control | awk '{print $3}') == "bbr" ]]; then
         echo -e "${green}BBR has been enabled successfully.${plain}"
     else
@@ -566,6 +542,7 @@ ssl_cert_issue_main() {
     echo -e "${green}\t1.${plain} Get SSL"
     echo -e "${green}\t2.${plain} Revoke"
     echo -e "${green}\t3.${plain} Force Renew"
+    echo -e "${green}\t4.${plain} Self-signed Certificate"
     read -p "Choose an option: " choice
     case "$choice" in
         1) ssl_cert_issue ;;
@@ -579,12 +556,14 @@ ssl_cert_issue_main() {
             local domain=""
             read -p "Please enter your domain name to forcefully renew an SSL certificate: " domain
             ~/.acme.sh/acme.sh --renew -d ${domain} --force ;;
+        4)
+            generate_self_signed_cert
+            ;;
         *) echo "Invalid choice" ;;
     esac
 }
 
 ssl_cert_issue() {
-    # check for acme.sh first
     if ! command -v ~/.acme.sh/acme.sh &>/dev/null; then
         echo "acme.sh could not be found. we will install it"
         install_acme
@@ -593,7 +572,6 @@ ssl_cert_issue() {
             exit 1
         fi
     fi
-    # install socat second
     case "${release}" in
     ubuntu | debian | armbian)
         apt update && apt install socat -y
@@ -619,11 +597,9 @@ ssl_cert_issue() {
         LOGI "install socat succeed..."
     fi
 
-    # get the domain here,and we need verify it
     local domain=""
     read -p "Please enter your domain name:" domain
     LOGD "your domain is:${domain},check it..."
-    # here we need to judge whether there exists cert already
     local currentCert=$(~/.acme.sh/acme.sh --list | tail -1 | awk '{print $1}')
 
     if [ ${currentCert} == ${domain} ]; then
@@ -635,7 +611,6 @@ ssl_cert_issue() {
         LOGI "your domain is ready for issuing cert now..."
     fi
 
-    # create a directory for install cert
     certPath="/root/cert/${domain}"
     if [ ! -d "$certPath" ]; then
         mkdir -p "$certPath"
@@ -644,15 +619,12 @@ ssl_cert_issue() {
         mkdir -p "$certPath"
     fi
 
-    # get needed port here
     local WebPort=80
     read -p "please choose which port do you use,default will be 80 port:" WebPort
     if [[ ${WebPort} -gt 65535 || ${WebPort} -lt 1 ]]; then
         LOGE "your input ${WebPort} is invalid,will use default port"
     fi
     LOGI "will use port:${WebPort} to issue certs,please make sure this port is open..."
-    # NOTE:This should be handled by user
-    # open the port and kill the occupied progress
     ~/.acme.sh/acme.sh --set-default-ca --server letsencrypt
     ~/.acme.sh/acme.sh --issue -d ${domain} --standalone --httpport ${WebPort}
     if [ $? -ne 0 ]; then
@@ -662,7 +634,6 @@ ssl_cert_issue() {
     else
         LOGE "issue certs succeed,installing certs..."
     fi
-    # install cert
     ~/.acme.sh/acme.sh --installcert -d ${domain} \
         --key-file /root/cert/${domain}/privkey.pem \
         --fullchain-file /root/cert/${domain}/fullchain.pem
@@ -804,6 +775,61 @@ ssl_cert_issue_CF() {
     esac
 }
 
+generate_self_signed_cert() {
+    cert_dir="/etc/sing-box"
+    mkdir -p "$cert_dir"
+    LOGI "Choose certificate type:"
+    echo -e "${green}\t1.${plain} Ed25519 (*recommended*)"
+    echo -e "${green}\t2.${plain} RSA 2048"
+    echo -e "${green}\t3.${plain} RSA 4096"
+    echo -e "${green}\t4.${plain} ECDSA prime256v1"
+    echo -e "${green}\t5.${plain} ECDSA secp384r1"
+    read -p "Enter your choice [1-5, default 1]: " cert_type
+    cert_type=${cert_type:-1}
+
+    case "$cert_type" in
+        1)
+            algo="ed25519"
+            key_opt="-newkey ed25519"
+            ;;
+        2)
+            algo="rsa"
+            key_opt="-newkey rsa:2048"
+            ;;
+        3)
+            algo="rsa"
+            key_opt="-newkey rsa:4096"
+            ;;
+        4)
+            algo="ecdsa"
+            key_opt="-newkey ec -pkeyopt ec_paramgen_curve:prime256v1"
+            ;;
+        5)
+            algo="ecdsa"
+            key_opt="-newkey ec -pkeyopt ec_paramgen_curve:secp384r1"
+            ;;
+        *)
+            algo="ed25519"
+            key_opt="-newkey ed25519"
+            ;;
+    esac
+
+    LOGI "Generating self-signed certificate ($algo)..."
+    sudo openssl req -x509 -nodes -days 3650 $key_opt \
+        -keyout "${cert_dir}/self.key" \
+        -out "${cert_dir}/self.crt" \
+        -subj "/CN=myserver"
+    if [[ $? -eq 0 ]]; then
+        sudo chmod 600 "${cert_dir}/self."*
+        LOGI "Self-signed certificate generated successfully!"
+        LOGI "Certificate path: ${cert_dir}/self.crt"
+        LOGI "Key path: ${cert_dir}/self.key"
+    else
+        LOGE "Failed to generate self-signed certificate."
+    fi
+    before_show_menu
+}
+
 show_usage() {
     echo -e "S-UI Control Menu Usage"
     echo -e "------------------------------------------"