Initial commit on Forgejo

Fresh repository history for elektrine/elektrine-haraka hosted at
https://git.elektrine.com/elektrine/elektrine-haraka.

plugins/elektrine_rcpt_verify.js

@@ -0,0 +1,86 @@
+/**
+ * Elektrine Recipient Verification Plugin
+ * 
+ * Verifies that recipients exist before accepting email.
+ * Prevents backscatter attacks from bouncing to spoofed senders.
+ */
+
+'use strict';
+
+const constants = require('haraka-constants');
+
+// Shared library modules
+const { config, http: httpClient, domains } = require('../lib');
+
+exports.register = function() {
+    const plugin = this;
+    
+    // Load configuration
+    plugin.cfg = config.load();
+    
+    // Log initial domains (may be updated dynamically from Phoenix)
+    const local_domains = domains.get_local_domains();
+    plugin.loginfo(`Recipient verification enabled for: ${local_domains.join(', ')}`);
+    
+    // Log cache status periodically (every 10 minutes)
+    setInterval(() => {
+        const cache_status = domains.get_cache_status();
+        if (cache_status.cached) {
+            plugin.logdebug(`Domain cache: ${cache_status.domains.length} domains, age: ${Math.round(cache_status.age_ms / 1000)}s`);
+        }
+    }, 10 * 60 * 1000);
+};
+
+exports.hook_rcpt = function(next, connection, params) {
+    const plugin = this;
+    const rcpt = params[0];
+    
+    if (!rcpt || !rcpt.host) {
+        return next();
+    }
+    
+    const recipient_domain = rcpt.host.toLowerCase();
+    const recipient_email = rcpt.address().toLowerCase();
+    
+    // Check if this is for a local domain
+    const is_local = domains.is_local_domain(recipient_domain);
+    
+    if (!is_local) {
+        // External domain - only allow if authenticated (relay)
+        // Check if connection is authenticated (handled by auth/auth_proxy plugin)
+        if (connection.relaying) {
+            plugin.loginfo(`Authenticated relay to external domain: ${recipient_email}`);
+            return next();
+        }
+        
+        // Not authenticated and not local domain - reject (prevent open relay)
+        plugin.logwarn(`Rejecting relay attempt to external domain: ${recipient_email}`);
+        return next(constants.DENY, `Relay not permitted for ${recipient_domain}`);
+    }
+    
+    // Local domain - verify recipient exists in Phoenix
+    plugin.loginfo(`Verifying recipient exists: ${recipient_email}`);
+    
+    // Verify with Phoenix app
+    httpClient.verify_recipient(plugin.cfg.verify_url, recipient_email, {
+        api_key: plugin.cfg.phoenix_api_key,
+        timeout: plugin.cfg.verify_timeout,
+        logger: (msg) => plugin.logdebug(msg)
+    })
+    .then((exists) => {
+        if (exists) {
+            plugin.loginfo(`Recipient verified: ${recipient_email}`);
+            return next(constants.OK);
+        } else {
+            plugin.logwarn(`Recipient does not exist: ${recipient_email}`);
+            return next(constants.DENY, `Recipient ${recipient_email} does not exist`);
+        }
+    })
+    .catch((err) => {
+        plugin.logerror(`Recipient verification failed: ${err.message}`);
+        // On error, defer (temp fail) so the sending server retries later
+        // This avoids accepting mail for potentially non-existent recipients
+        // which would cause backscatter bounces
+        return next(constants.DENYSOFT, 'Temporary recipient verification failure, please retry');
+    });
+};