fix: handle domain names in IP4 configuration variable

Previously, when the IP4 variable contained a domain name instead of an actual IP address, the SNI validation would fail and force the use of self-signed certificates. This update adds detection and resolution of domain names in the IP4 variable, ensuring proper DNS comparison when checking if the SNI domain points to the server.

core/scripts/hysteria2/change_sni.sh

@@ -10,6 +10,7 @@ else
     echo "Error: Config file $CONFIG_ENV not found."
     exit 1
 fi
+
 update_sni() {
     local sni=$1
     local server_ip
@@ -21,10 +22,21 @@ update_sni() {
     fi
 
     if [ -n "$IP4" ]; then
+        if [[ $IP4 =~ ^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
             server_ip="$IP4"
             echo "Using server IP from config: $server_ip"
         else
-        server_ip=$(curl -s ifconfig.me)
+            domain_ip=$(dig +short "$IP4" A | head -n 1)
+            if [ -n "$domain_ip" ]; then
+                server_ip="$domain_ip"
+                echo "Resolved domain $IP4 to IP: $server_ip"
+            else
+                server_ip=$(curl -s -4 ifconfig.me)
+                echo "Could not resolve domain $IP4. Using auto-detected server IP: $server_ip"
+            fi
+        fi
+    else
+        server_ip=$(curl -s -4 ifconfig.me)
         echo "Using auto-detected server IP: $server_ip"
     fi