From 3299a77da3d5e4ddd1269ddae3b6f6f8aa9e43e5 Mon Sep 17 00:00:00 2001
From: "Sijie.Sun" <sunsijie@buaa.edu.cn>
Date: Sun, 24 Aug 2025 18:24:42 +0800
Subject: [PATCH] make magic dns domain check robust (#1288)

---
 easytier/src/instance/dns_server/config.rs    |  2 +-
 .../instance/dns_server/server_instance.rs    | 25 +++++--------------
 easytier/src/instance/dns_server/tests.rs     | 23 +++++++++++++----
 3 files changed, 25 insertions(+), 25 deletions(-)

diff --git a/easytier/src/instance/dns_server/config.rs b/easytier/src/instance/dns_server/config.rs
index e249ecf..d00f8a3 100644
--- a/easytier/src/instance/dns_server/config.rs
+++ b/easytier/src/instance/dns_server/config.rs
@@ -68,7 +68,7 @@ pub struct Record {
 }
 
 impl Record {
-    fn name(&self) -> anyhow::Result<rr::Name> {
+    pub fn name(&self) -> anyhow::Result<rr::Name> {
         let name = rr::Name::from_str(self.name.as_str())?;
         Ok(name)
     }
diff --git a/easytier/src/instance/dns_server/server_instance.rs b/easytier/src/instance/dns_server/server_instance.rs
index c25d21b..e78a0e1 100644
--- a/easytier/src/instance/dns_server/server_instance.rs
+++ b/easytier/src/instance/dns_server/server_instance.rs
@@ -70,20 +70,6 @@ pub(super) struct MagicDnsServerInstanceData {
 }
 
 impl MagicDnsServerInstanceData {
-    fn is_valid_subdomain_label(s: &str) -> bool {
-        let s = s.trim();
-
-        // 长度检查：1-63 个字符
-        if s.is_empty() || s.len() > 63 {
-            return false;
-        }
-
-        // 检查每个字符是否合法，并确保不以 '-' 开头或结尾
-        s.chars().all(|c| matches!(c, 'a'..='z' | '0'..='9' | '-'))
-            && !s.starts_with('-')
-            && !s.ends_with('-')
-    }
-
     pub async fn update_dns_records<'a, T: Iterator<Item = &'a Route>>(
         &self,
         routes: T,
@@ -95,11 +81,6 @@ impl MagicDnsServerInstanceData {
                 continue;
             }
 
-            // check host name valid for dns
-            if !Self::is_valid_subdomain_label(&route.hostname) {
-                continue;
-            }
-
             let Some(ipv4_addr) = route.ipv4_addr.unwrap_or_default().address else {
                 continue;
             };
@@ -111,6 +92,12 @@ impl MagicDnsServerInstanceData {
                 .ttl(Duration::from_secs(1))
                 .build()?;
 
+            // check record name valid for dns
+            if let Err(e) = record.name() {
+                tracing::error!("Invalid subdomain label: {}", e);
+                continue;
+            }
+
             records.push(record);
         }
 
diff --git a/easytier/src/instance/dns_server/tests.rs b/easytier/src/instance/dns_server/tests.rs
index 443d4cb..e750323 100644
--- a/easytier/src/instance/dns_server/tests.rs
+++ b/easytier/src/instance/dns_server/tests.rs
@@ -84,11 +84,23 @@ async fn test_magic_dns_server_instance() {
             .await
             .unwrap();
 
-    let routes = vec![Route {
-        hostname: "test1".to_string(),
-        ipv4_addr: Some(Ipv4Inet::from_str("8.8.8.8/24").unwrap().into()),
-        ..Default::default()
-    }];
+    let routes = vec![
+        Route {
+            hostname: "test1".to_string(),
+            ipv4_addr: Some(Ipv4Inet::from_str("8.8.8.8/24").unwrap().into()),
+            ..Default::default()
+        },
+        Route {
+            hostname: "中文".to_string(),
+            ipv4_addr: Some(Ipv4Inet::from_str("8.8.8.8/24").unwrap().into()),
+            ..Default::default()
+        },
+        Route {
+            hostname: ".invalid".to_string(),
+            ipv4_addr: Some(Ipv4Inet::from_str("8.8.8.8/24").unwrap().into()),
+            ..Default::default()
+        },
+    ];
     dns_server_inst
         .data
         .update_dns_records(routes.iter(), DEFAULT_ET_DNS_ZONE)
@@ -96,6 +108,7 @@ async fn test_magic_dns_server_instance() {
         .unwrap();
 
     check_dns_record(&fake_ip, "test1.et.net", "8.8.8.8").await;
+    check_dns_record(&fake_ip, "中文.et.net", "8.8.8.8").await;
 }
 
 #[tokio::test]