on ipv6 hostname remove brackets for correct getRelayData response object

Author: NickOvt

lib/tools.js

@@ -390,8 +390,12 @@ function getRelayData(url) {
     } catch {
         urlparts = {};
     }
+    let hostname = urlparts.hostname || '';
+    if (/^\[[^\]]+\]$/.test(hostname)) {
+        hostname = hostname.slice(1, -1);
+    }
     let targetMx = {
-        host: urlparts.hostname,
+        host: hostname,
         port: urlparts.port || 25,
         auth:
             urlparts.username || urlparts.password
@@ -401,8 +405,8 @@ function getRelayData(url) {
                   }
                 : false,
         secure: urlparts.protocol === 'smtps:',
-        A: [].concat(net.isIPv4(urlparts.hostname) ? urlparts.hostname : []),
-        AAAA: [].concat(net.isIPv6(urlparts.hostname) ? urlparts.hostname : [])
+        A: [].concat(net.isIPv4(hostname) ? hostname : []),
+        AAAA: [].concat(net.isIPv6(hostname) ? hostname : [])
     };
     let data = {
         mx: [