feat: improve set dns logic

scripts/set_dns.sh

@@ -1,57 +1,66 @@
 #!/bin/bash
 
-function is_valid_ip() {
+# 验证IPv4地址格式
+function is_valid_ipv4() {
     local ip=$1
     local IFS='.'
     local -a octets
 
-    if [[ ! $ip =~ ^([0-9]+\.){3}[0-9]+$ ]]; then
-        return 1
-    fi
-
+    [[ ! $ip =~ ^([0-9]+\.){3}[0-9]+$ ]] && return 1
     read -r -a octets <<<"$ip"
-
-    if [ "${#octets[@]}" -ne 4 ]; then
-        return 1
-    fi
+    [ "${#octets[@]}" -ne 4 ] && return 1
 
     for octet in "${octets[@]}"; do
         if ! [[ "$octet" =~ ^[0-9]+$ ]] || ((octet < 0 || octet > 255)); then
             return 1
         fi
     done
-
     return 0
 }
 
-if [ $# -lt 1 ]; then
-    echo "Usage: $0 <hardware_port>"
-    exit 1
-fi
+# 验证IPv6地址格式
+function is_valid_ipv6() {
+    local ip=$1
+    if [[ ! $ip =~ ^([0-9a-fA-F]{0,4}:){1,7}[0-9a-fA-F]{0,4}$ ]] && \
+       [[ ! $ip =~ ^(([0-9a-fA-F]{0,4}:){0,7}:|(:[0-9a-fA-F]{0,4}:){0,6}:[0-9a-fA-F]{0,4})$ ]]; then
+        return 1
+    fi
+    return 0
+}
 
-if ! is_valid_ip "$1"; then
-    echo "$1 is not a valid IP address."
-    exit 1
-fi
+# 验证IP地址是否为有效的IPv4或IPv6
+function is_valid_ip() {
+    is_valid_ipv4 "$1" || is_valid_ipv6 "$1"
+}
 
+# 检查参数
+[ $# -lt 1 ] && echo "Usage: $0 <IP address>" && exit 1
+! is_valid_ip "$1" && echo "$1 is not a valid IP address." && exit 1
+
+# 获取网络接口和硬件端口
 nic=$(route -n get default | grep "interface" | awk '{print $2}')
 hardware_port=$(networksetup -listallhardwareports | awk -v dev="$nic" '
-    /Hardware Port:/{
-        port=$0; gsub("Hardware Port: ", "", port)
-    } 
-    /Device: /{
-        if ($2 == dev) {
-            print port; 
-            exit
-        }
-    }
+    /Hardware Port:/{port=$0; gsub("Hardware Port: ", "", port)} 
+    /Device: /{if ($2 == dev) {print port; exit}}
 ')
 
+# 获取当前DNS设置
 original_dns=$(networksetup -getdnsservers "$hardware_port")
 
-if [ ${#original_dns} -le 15 ]; then
-    if [ -n "$original_dns" ]; then
-        echo $original_dns >original_dns.txt
-        networksetup -setdnsservers "$hardware_port" "$1"
+# 检查当前DNS设置是否有效
+is_valid_dns=false
+for ip in $original_dns; do
+    ip=$(echo "$ip" | tr -d '[:space:]')
+    if [ -n "$ip" ] && (is_valid_ipv4 "$ip" || is_valid_ipv6 "$ip"); then
+        is_valid_dns=true
+        break
     fi
+done
+
+# 更新DNS设置
+if [ "$is_valid_dns" = false ]; then
+    echo "empty" > original_dns.txt
+else
+    echo "$original_dns" > original_dns.txt
 fi
+networksetup -setdnsservers "$hardware_port" "$1"