From 5e7fcdac8fe3ce13ebb2fce536b5882fdb9adcde Mon Sep 17 00:00:00 2001
From: holger krekel <holger@merlinux.eu>
Date: Fri, 8 May 2026 22:06:18 +0200
Subject: [PATCH] add imap metadata reading of smtp max recipients

---
 src/constants.rs      |  3 ---
 src/context.rs        | 24 ++++++++++++++++--------
 src/imap.rs           | 17 ++++++++++++++++-
 src/sql/migrations.rs |  9 +++++++++
 4 files changed, 41 insertions(+), 12 deletions(-)

diff --git a/src/constants.rs b/src/constants.rs
index 9b109c0f5..439144186 100644
--- a/src/constants.rs
+++ b/src/constants.rs
@@ -204,9 +204,6 @@ pub const MAX_RCVD_IMAGE_PIXELS: u32 = 50_000_000;
 // `max_smtp_rcpt_to` in the provider db.
 pub(crate) const DEFAULT_MAX_SMTP_RCPT_TO: usize = 50;
 
-/// Same as `DEFAULT_MAX_SMTP_RCPT_TO`, but for chatmail relays.
-pub(crate) const DEFAULT_CHATMAIL_MAX_SMTP_RCPT_TO: usize = 999;
-
 /// How far the last quota check needs to be in the past to be checked by the background function (in seconds).
 pub(crate) const DC_BACKGROUND_FETCH_QUOTA_CHECK_RATELIMIT: u64 = 12 * 60 * 60; // 12 hours
 
diff --git a/src/context.rs b/src/context.rs
index 95ce3c777..faf1778f3 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -589,18 +589,26 @@ impl Context {
 
     /// Returns maximum number of recipients the provider allows to send a single email to.
     pub(crate) async fn get_max_smtp_rcpt_to(&self) -> Result<usize> {
-        let is_chatmail = self.is_chatmail().await?;
+        if let Some(limit) = self
+            .sql
+            .query_row_optional(
+                "SELECT t.max_smtp_rcpt_to
+                 FROM transports t
+                 JOIN config c ON c.keyname='configured_addr' AND c.value=t.addr",
+                (),
+                |row| row.get::<_, Option<u32>>(0),
+            )
+            .await?
+            .flatten()
+        {
+            return Ok(limit as usize);
+        }
+
         let val = self
             .get_configured_provider()
             .await?
             .and_then(|provider| provider.opt.max_smtp_rcpt_to)
-            .map_or_else(
-                || match is_chatmail {
-                    true => constants::DEFAULT_CHATMAIL_MAX_SMTP_RCPT_TO,
-                    false => constants::DEFAULT_MAX_SMTP_RCPT_TO,
-                },
-                usize::from,
-            );
+            .map_or(constants::DEFAULT_MAX_SMTP_RCPT_TO, usize::from);
         Ok(val)
     }
 
diff --git a/src/imap.rs b/src/imap.rs
index 892253bc2..c321a578a 100644
--- a/src/imap.rs
+++ b/src/imap.rs
@@ -1503,7 +1503,7 @@ impl Session {
             .get_metadata(
                 mailbox,
                 options,
-                "(/shared/comment /shared/admin /shared/vendor/deltachat/irohrelay /shared/vendor/deltachat/turn)",
+                "(/shared/comment /shared/admin /shared/vendor/deltachat/irohrelay /shared/vendor/deltachat/turn /shared/vendor/deltachat/maxsmtprecipients)",
             )
             .await?;
         for m in metadata {
@@ -1539,6 +1539,21 @@ impl Session {
                         }
                     }
                 }
+                "/shared/vendor/deltachat/maxsmtprecipients" => {
+                    if let Some(value) = m.value.and_then(|v| v.parse::<u32>().ok()) {
+                        let transport_id = self.transport_id();
+                        context
+                            .sql
+                            .execute(
+                                "UPDATE transports \
+                                 SET max_smtp_rcpt_to=? WHERE id=?",
+                                (value, transport_id),
+                            )
+                            .await
+                            .log_err(context)
+                            .ok();
+                    }
+                }
                 _ => {}
             }
         }
diff --git a/src/sql/migrations.rs b/src/sql/migrations.rs
index ce5cf718c..6a4061f26 100644
--- a/src/sql/migrations.rs
+++ b/src/sql/migrations.rs
@@ -2385,6 +2385,15 @@ UPDATE msgs SET state=19 WHERE state=24; -- Change OutPreparing to OutFailed.
         .await?;
     }
 
+    inc_and_check(&mut migration_version, 153)?;
+    if dbversion < migration_version {
+        sql.execute_migration(
+            "ALTER TABLE transports ADD COLUMN max_smtp_rcpt_to INTEGER DEFAULT NULL",
+            migration_version,
+        )
+        .await?;
+    }
+
     let new_version = sql
         .get_raw_config_int(VERSION_CFG)
         .await?