Add config option for cname records

WebThingsIO · Sep 30, 2024 · 130dfd4 · 130dfd4
1 parent 492a819
commit 130dfd4
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diff --git a/config/config.toml b/config/config.toml
@@ -25,6 +25,10 @@ txt_records = [
   [ "_psl", "https://github.com/publicsuffix/list/pull/XYZ" ],
   [ "@", "something useful" ],
 ]
+cname_records = [
+  [ "subdomain.mydomain.org", "mydomain.org" ],
+  [ "subdomain2.mydomain.org", "mydomain.org" ],
+]
 soa_record = "ns1.mydomain.org. dns-admin.mydomain.org. 2018082801 900 900 1209600 60"
 www_addresses = [
   "10.11.12.13",

diff --git a/src/config.rs b/src/config.rs
@@ -41,6 +41,7 @@ pub struct PdnsOptions {
     pub mx_records: Vec<String>,
     pub ns_records: Vec<Vec<String>>,
     pub txt_records: Vec<Vec<String>>,
+    pub cname_records: Vec<Vec<String>>,
     pub soa_record: String,
     pub www_addresses: Vec<String>,
     pub geoip: GeoIp,

diff --git a/src/pdns.rs b/src/pdns.rs
@@ -277,6 +277,37 @@ fn build_txt_response(
     records
 }
 
+// Returns a CNAME record for a given qname.
+fn build_config_cname_response(
+    qname: &str,
+    config: &Config,
+) -> Vec<PdnsLookupResponse> {
+    let sanitized_qname = remove_trailing_dot(qname);
+    let mut records = vec![];
+    for cname in &config.options.pdns.cname_records {
+        if cname[0] == sanitized_qname {
+            records.push(PdnsLookupResponse {
+                qtype: "CNAME".to_owned(),
+                qname: qname.to_owned(),
+                content: cname[1].to_owned(),
+                ttl: config.options.pdns.dns_ttl,
+                domain_id: None,
+                scope_mask: None,
+                auth: None,
+            });
+        }
+    }
+
+    records
+}
+
+fn remove_trailing_dot(s: &str) -> &str {
+    match s.chars().last() {
+        Some('.') => &s[0..s.len() - 1],
+        _ => s
+    }
+}
+
 // Returns a TXT record with the DNS challenge content.
 fn build_dns_challenge_response(
     qname: &str,
@@ -476,6 +507,13 @@ fn handle_lookup(req: PdnsRequest, config: &Config) -> Result<PdnsResponse, Stri
         }
     }
 
+    if qtype == "CNAME" || qtype == "ANY" {
+        // Add "CNAME" records.
+        for record in build_config_cname_response(&original_qname, config) {
+            result.push(PdnsResponseParams::Lookup(record));
+        }
+    }
+
     let conn = config.db.get_connection();
     if conn.is_err() {
         error!(
@@ -979,6 +1017,33 @@ mod tests {
             })
         );
 
+        // A query for a subdomain
+        let request = build_lookup(
+            "lookup",
+            Some("CNAME"),
+            Some("subdomain.mydomain.org."),
+            None,
+        );
+        let body = serde_json::to_string(&request).unwrap();
+        stream.write_all(body.as_bytes()).unwrap();
+        stream.write_all(b"\n").unwrap();
+
+        let len = stream.read(&mut answer).unwrap();
+        let response: serde_json::Value = serde_json::from_slice(&answer[..len]).unwrap();
+        assert_json_eq!(
+            response,
+            json!({
+                "result": [
+                    {
+                        "qtype": "CNAME",
+                        "qname": "subdomain.mydomain.org.",
+                        "content": "mydomain.org",
+                        "ttl": 86400,
+                    }
+                ],
+            })
+        );
+
         // A query for ns1
         let request = build_lookup("lookup", Some("A"), Some("ns1.mydomain.org."), None);
         let body = serde_json::to_string(&request).unwrap();