Make the multi_domain smtp transport option expanded

4 files changed, 46 insertions, 21 deletions

diff --git a/src/src/deliver.c b/src/src/deliver.c
index d33cf799a..5000f1cbc 100644
--- a/src/src/deliver.c
+++ b/src/src/deliver.c
@@ -3844,9 +3844,20 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
     }
 
   /* Get the flag which specifies whether the transport can handle different
-  domains that nevertheless resolve to the same set of hosts. */
-
-  multi_domain = tp->multi_domain;
+  domains that nevertheless resolve to the same set of hosts. If it needs
+  expanding, get variables set: $address_data, $domain_data, $localpart_data,
+  $host, $host_address, $host_port. */
+  if (tp->expand_multi_domain)
+    deliver_set_expansions(addr);
+
+  if (exp_bool(addr, US"transport", tp->name, D_transport,
+		US"multi_domain", tp->multi_domain, tp->expand_multi_domain,
+		&multi_domain) != OK)
+    {
+    deliver_set_expansions(NULL);
+    remote_post_process(addr, LOG_MAIN|LOG_PANIC, addr->message, fallback);
+    continue;
+    }
 
   /* Get the maximum it can handle in one envelope, with zero meaning
   unlimited, which is forced for the MUA wrapper case. */
@@ -3915,26 +3926,35 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
   entirely different domains. The host list pointers can be NULL in the case
   where the hosts are defined in the transport. There is also a configured
   maximum limit of addresses that can be handled at once (see comments above
-  for how it is computed). */
+  for how it is computed).
+  If the transport does not handle multiple domains, enforce that also,
+  and if it might need a per-address check for this, re-evaluate it.
+  */
 
   while ((next = *anchor) != NULL && address_count < address_count_max)
     {
-    if ((multi_domain || Ustrcmp(next->domain, addr->domain) == 0)
-        &&
-        tp == next->transport
-        &&
-        same_hosts(next->host_list, addr->host_list)
-        &&
-        same_strings(next->p.errors_address, addr->p.errors_address)
-        &&
-        same_headers(next->p.extra_headers, addr->p.extra_headers)
-        &&
-        same_ugid(tp, next, addr)
-        &&
-        (next->p.remove_headers == addr->p.remove_headers ||
-          (next->p.remove_headers != NULL &&
-           addr->p.remove_headers != NULL &&
-           Ustrcmp(next->p.remove_headers, addr->p.remove_headers) == 0)))
+    BOOL md;
+    if (  (multi_domain || Ustrcmp(next->domain, addr->domain) == 0)
+       && tp == next->transport
+       && same_hosts(next->host_list, addr->host_list)
+       && same_strings(next->p.errors_address, addr->p.errors_address)
+       && same_headers(next->p.extra_headers, addr->p.extra_headers)
+       && same_ugid(tp, next, addr)
+       && (  next->p.remove_headers == addr->p.remove_headers
+	  || (  next->p.remove_headers != NULL
+	     && addr->p.remove_headers != NULL
+	     && Ustrcmp(next->p.remove_headers, addr->p.remove_headers) == 0
+	  )  )
+       && (  !multi_domain
+	  || (  (
+		!tp->expand_multi_domain || (deliver_set_expansions(next), 1),
+	        exp_bool(addr,
+		    US"transport", next->transport->name, D_transport,
+		    US"multi_domain", next->transport->multi_domain,
+		    next->transport->expand_multi_domain, &md) == OK
+	        )
+	     && md
+       )  )  )
       {
       *anchor = next->next;
       next->next = NULL;
@@ -3944,6 +3964,7 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
       address_count++;
       }
     else anchor = &(next->next);
+    deliver_set_expansions(NULL);
     }
 
   /* If we are acting as an MUA wrapper, all addresses must go in a single
diff --git a/src/src/globals.c b/src/src/globals.c
index fb705d9d8..f7c67d76f 100644
--- a/src/src/globals.c
+++ b/src/src/globals.c
@@ -1356,6 +1356,7 @@ transport_instance  transport_defaults = {
     NULL,                     /* batch_id */
     NULL,                     /* home_dir */
     NULL,                     /* current_dir */
+    NULL,                     /* expand-multi-domain */
     TRUE,                     /* multi-domain */
     FALSE,                    /* overrides_hosts */
     100,                      /* max_addresses */
diff --git a/src/src/structs.h b/src/src/structs.h
index 259d9af71..2250bbbde 100644
--- a/src/src/structs.h
+++ b/src/src/structs.h
@@ -148,6 +148,7 @@ typedef struct transport_instance {
   uschar *home_dir;               /* ) Used only for local transports   */
   uschar *current_dir;            /* )                                  */
                                   /**************************************/
+  uschar *expand_multi_domain;    /* )                                  */
   BOOL    multi_domain;           /* )                                  */
   BOOL    overrides_hosts;        /* ) Used only for remote transports  */
   int     max_addresses;          /* )                                  */
diff --git a/src/src/transports/smtp.c b/src/src/transports/smtp.c
index 33d357f7a..69bbc4d0c 100644
--- a/src/src/transports/smtp.c
+++ b/src/src/transports/smtp.c
@@ -19,6 +19,8 @@ before the lower case letters). Some live in the transport_instance block so as
 to be publicly visible; these are flagged with opt_public. */
 
 optionlist smtp_transport_options[] = {
+  { "*expand_multi_domain",             opt_stringptr | opt_hidden | opt_public,
+      (void *)offsetof(transport_instance, expand_multi_domain) },
   { "*expand_retry_include_ip_address", opt_stringptr | opt_hidden,
        (void *)(offsetof(smtp_transport_options_block, expand_retry_include_ip_address)) },
 
@@ -145,7 +147,7 @@ optionlist smtp_transport_options[] = {
       (void *)offsetof(smtp_transport_options_block, lmtp_ignore_quota) },
   { "max_rcpt",             opt_int | opt_public,
       (void *)offsetof(transport_instance, max_addresses) },
-  { "multi_domain",         opt_bool | opt_public,
+  { "multi_domain",         opt_expand_bool | opt_public,
       (void *)offsetof(transport_instance, multi_domain) },
   { "port",                 opt_stringptr,
       (void *)offsetof(smtp_transport_options_block, port) },