Do not defer if MX server was not found

zone-eu · Jan 19, 2024 · cd5e1a2 · cd5e1a2
1 parent 3769fc3
commit cd5e1a2
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Showing 5 changed files with 640 additions and 602 deletions.
diff --git a/bin/check-bounce.js b/bin/check-bounce.js
@@ -12,9 +12,7 @@ process.stdin.on('data', chunk => {
 });
 
 process.stdin.on('end', () => {
-    let str = Buffer.concat(chunks)
-        .toString()
-        .trim();
+    let str = Buffer.concat(chunks).toString().trim();
     let bounceInfo = bounces.check(str);
     console.log('data     : %s', str.replace(/\n/g, '\n' + ' '.repeat(11)));
     Object.keys(bounceInfo || {}).forEach(key => {

diff --git a/lib/ip-tools.js b/lib/ip-tools.js
@@ -31,6 +31,8 @@ class RedisCache {
             return callback();
         }
 
+        log.silly(logKey, 'DNSCACHE SET key=%s value=%s', key, JSON.stringify(value));
+
         db.redis
             .multi()
             .set('dns:' + key, JSON.stringify(value))

diff --git a/lib/sender.js b/lib/sender.js
@@ -30,7 +30,7 @@ const DEFAULT_DEFER_TIMES = [
     240 /* 28h */, 240 /* 32h */, 240 /* 36h */, 240 /* 40h */, 240 /* 44h */, 240 /* 48h */
 ].map(v => v * 60 * 1000);
 
-const POLICY_RESPONSE = '550 Failed to establish a TLS connection to the MX server as requested by policy';
+const POLICY_RESPONSE = 'Failed to establish a TLS connection to the MX server as requested by policy';
 
 class Sender extends EventEmitter {
     constructor(clientId, connectionId, zone, sendCommand, queue, connectionPool) {
@@ -304,9 +304,12 @@ class Sender extends EventEmitter {
                                     // connection reached unexpected close event
                                     let host =
                                         (connection && connection.options && (connection.options.servername || connection.options.host)) || delivery.domain;
-                                    let err = new Error('Connection to ' + host + ' closed unexpectedly');
-                                    err.response = '450 Connection to ' + host + ' closed unexpectedly';
-                                    err.category = 'network';
+
+                                    let error = new Error(`Connection to ${host} closed unexpectedly`);
+                                    error.response = `Network error: ${err.message}`;
+                                    error.category = 'network';
+                                    error.temporary = true;
+
                                     return handleError(delivery, connection, err);
                                 }, 1000).unref();
                             });
@@ -694,16 +697,23 @@ class Sender extends EventEmitter {
                 action: err.httpResponse >= 400 && err.httpResponse < 500 ? 'reject' : 'defer',
                 category: 'http',
                 message: err.response || err.message,
-                code: err.httpResponse || 488,
+                code: err.httpResponse,
+                status: false
+            };
+        } else if (['dns', 'network', 'policy'].includes(err.category)) {
+            // preset categories from mx-connect etc
+            bounce = {
+                action: err.temporary || err.action === 'defer' ? 'defer' : 'reject',
+                category: err.category,
+                message: err.response || err.message,
                 status: false
             };
         } else if (!err.responseCode && !/^\d{3}\b/.test(err.response || err.message)) {
             // timeouts, node network errors etc.
             bounce = {
                 action: 'defer',
-                category: 'connection',
+                category: 'network',
                 message: err.response || err.message,
-                code: 488,
                 status: false
             };
         } else {
@@ -878,8 +888,12 @@ class Sender extends EventEmitter {
 
                 if (domainData && domainData.error) {
                     let err = new Error(domainData.error);
-                    err.response = domainData.response;
-                    err.category = domainData.category;
+                    for (let key of ['response', 'category', 'temporary', 'code']) {
+                        if (domainData[key]) {
+                            err[key] = domainData[key];
+                        }
+                    }
+
                     return callback(err);
                 }
 
@@ -894,13 +908,15 @@ class Sender extends EventEmitter {
                         domainData.error = err.message;
                         domainData.response = err.response;
                         domainData.category = err.category;
+                        domainData.temporary = err.temporary;
+                        domainData.code = err.code;
 
                         if (err.lastErr && [err.lastErr.errno, err.lastErr.code].includes('ETIMEDOUT')) {
                             // most probably a firewall issue or a server that does not have MX running
                             ttl = 15 * 60 * 1000;
                         } else {
-                            // auto defer all messages to this server for the next 10 minutes
-                            ttl = 10 * 60 * 1000;
+                            // auto defer all messages to this server for the next 2 minutes
+                            ttl = 2 * 60 * 1000;
                         }
                         cmd = {
                             cmd: 'SETCACHE',
@@ -1170,17 +1186,21 @@ class Sender extends EventEmitter {
                     if (/disconnected\s+before\s+secure\s+TLS\s+connection\s+was\s+established/i.test(err.message) || err.cert) {
                         if (enforceTLS) {
                             // policy violation
-                            err.response = POLICY_RESPONSE + (err.reason ? '. ' + err.reason : '');
+                            err.response = `Policy error: ${POLICY_RESPONSE}${err.reason ? `. ${err.reason}` : ''}`;
                             err.category = 'policy';
+                            err.temporary = false;
                         } else {
                             // try to reconnect without TLS
                             err.code = 'ETLS';
                         }
                     }
 
-                    err.response = err.response || '450 Error connecting to ' + mx.host + '. ' + err.message;
+                    err.response = err.response || `Nework error: Error connecting to ${mx.host}. ${err.message}`;
                     err.category = err.category || 'network';
                     err.logtrail = logtrail;
+                    if (typeof err.temporary !== 'boolean') {
+                        err.temporary = true;
+                    }
 
                     if (
                         (err.code === 'ETLS' ||
@@ -1302,7 +1322,7 @@ class Sender extends EventEmitter {
                         returned = true;
                         connection.close();
                         let err = new Error('TLS is required');
-                        err.response = POLICY_RESPONSE;
+                        err.response = `Policy error: ${POLICY_RESPONSE}`;
                         err.category = 'policy';
                         return callback(err);
                     }