Fix MTA: Expand lists and resolve catch-all addresses when building autogenerated messages

crates/smtp/src/outbound/local.rs

@@ -100,7 +100,7 @@ impl MessageWrapper {
         for autogenerated in delivery_result.autogenerated {
             let mut message = server.new_message(autogenerated.sender_address, self.span_id);
             for rcpt in autogenerated.recipients {
-                message.add_recipient(rcpt, server).await;
+                message.expand_and_add_recipient(rcpt, server).await;
             }
 
             // Sign message

crates/smtp/src/queue/dsn.rs

@@ -39,7 +39,7 @@ impl SendDsn for Server {
             if let Some(dsn) = message.build_dsn(self).await {
                 let mut dsn_message = self.new_message("", message.span_id);
                 dsn_message
-                    .add_recipient(message.message.return_path.as_ref(), self)
+                    .expand_and_add_recipient(message.message.return_path.as_ref(), self)
                     .await;
 
                 // Sign message

crates/smtp/src/queue/spool.rs

@@ -16,6 +16,7 @@ use crate::queue::{
 use ahash::AHashSet;
 use common::config::smtp::queue::{ArchivedQueueExpiry, QueueName};
 use common::ipc::QueueEvent;
+use common::network::RcptResolution;
 use common::{KV_LOCK_QUEUE_MESSAGE, Server};
 use registry::schema::prelude::{ObjectType, Property};
 use registry::schema::structs::SpamTrainingSample;
@@ -568,9 +569,37 @@ impl MessageWrapper {
         true
     }
 
-    pub async fn add_recipient(&mut self, rcpt: impl AsRef<str>, server: &Server) {
-        // Resolve queue
-        self.message.recipients.push(Recipient::new(rcpt));
+    pub async fn expand_and_add_recipient(&mut self, rcpt: impl AsRef<str>, server: &Server) {
+        let rcpt = rcpt.as_ref();
+        match server
+            .rcpt_resolve(&rcpt.to_lowercase(), self.span_id)
+            .await
+        {
+            Ok(RcptResolution::Rewrite(rewritten)) => {
+                self.add_expanded_recipient(&rewritten, server).await;
+            }
+            Ok(RcptResolution::Expand(addrs)) => {
+                for addr in addrs.as_ref() {
+                    self.add_expanded_recipient(addr, server).await;
+                }
+            }
+            Ok(_) => {
+                self.add_expanded_recipient(rcpt, server).await;
+            }
+            Err(err) => {
+                trc::error!(
+                    err.span_id(self.span_id)
+                        .caused_by(trc::location!())
+                        .details("Failed to resolve recipient.")
+                        .ctx(trc::Key::To, rcpt.to_string())
+                );
+                self.add_expanded_recipient(rcpt, server).await;
+            }
+        }
+    }
+
+    pub async fn add_expanded_recipient(&mut self, rcpt: impl AsRef<str>, server: &Server) {
+        self.message.recipients.push(Recipient::new(rcpt.as_ref()));
         let queue = server.get_queue_or_default(
             &server
                 .eval_if::<String, _>(

crates/smtp/src/reporting/send.rs

@@ -57,7 +57,7 @@ impl MtaReportSend for Server {
         // Build message
         let mut message = self.new_message(from_addr, parent_session_id);
         for rcpt_ in rcpts {
-            message.add_recipient(rcpt_.as_ref(), self).await;
+            message.add_expanded_recipient(rcpt_.as_ref(), self).await;
         }
 
         // Sign message
@@ -104,7 +104,7 @@ impl MtaReportSend for Server {
         // Build message
         let mut message = self.new_message(from_addr.as_ref(), parent_session_id);
         for rcpt in rcpts {
-            message.add_recipient(rcpt, self).await;
+            message.add_expanded_recipient(rcpt, self).await;
         }
 
         // Sign message

crates/smtp/src/scripts/event_loop.rs

@@ -161,11 +161,11 @@ impl RunScript for Server {
                         let mut message = self.new_message(params.return_path.as_str(), session_id);
                         match recipient {
                             Recipient::Address(rcpt) => {
-                                message.add_recipient(rcpt, self).await;
+                                message.expand_and_add_recipient(rcpt, self).await;
                             }
                             Recipient::Group(rcpt_list) => {
                                 for rcpt in rcpt_list {
-                                    message.add_recipient(rcpt, self).await;
+                                    message.expand_and_add_recipient(rcpt, self).await;
                                 }
                             }
                             Recipient::List(list) => {