Callouts: a "hold" option for receipient-verify, which keeps the connection open...
[exim.git] / src / src / verify.c
index 9ff1807d4fdac01ff3b2d4551b78d2c6bae60c80..59add8c0004e1338c8320f736ca9a31c542f3639 100644 (file)
@@ -39,7 +39,7 @@ static tree_node *dnsbl_cache = NULL;
 #define MT_NOT 1
 #define MT_ALL 2
 
-static uschar cutthrough_response(char, uschar **, int);
+static uschar cutthrough_response(int, char, uschar **, int);
 
 
 
@@ -388,7 +388,7 @@ if (addr->transport == cutthrough.addr.transport)
       deliver_domain = addr->domain;
       transport_name = addr->transport->name;
 
-      host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
+      host_af = Ustrchr(host->address, ':') ? AF_INET6 : AF_INET;
 
       if (!smtp_get_interface(tf->interface, host_af, addr, &interface,
              US"callout") ||
@@ -411,7 +411,7 @@ if (addr->transport == cutthrough.addr.transport)
          smtp_write_command(&ctblock, FALSE, "RCPT TO:<%.1000s>\r\n",
            transport_rcpt_address(addr,
               addr->transport->rcpt_include_affixes)) >= 0 &&
-         cutthrough_response('2', &resp, CUTTHROUGH_DATA_TIMEOUT) == '2';
+         cutthrough_response(cutthrough.fd, '2', &resp, CUTTHROUGH_DATA_TIMEOUT) == '2';
 
        /* This would go horribly wrong if a callout fail was ignored by ACL.
        We punt by abandoning cutthrough on a reject, like the
@@ -429,7 +429,7 @@ if (addr->transport == cutthrough.addr.transport)
          }
        else
          {
-         cancel_cutthrough_connection("recipient rejected");
+         cancel_cutthrough_connection(TRUE, US"recipient rejected");
          if (!resp || errno == ETIMEDOUT)
            {
            HDEBUG(D_verify) debug_printf("SMTP timeout\n");
@@ -459,7 +459,7 @@ if (addr->transport == cutthrough.addr.transport)
       break;   /* host_list */
       }
 if (!done)
-  cancel_cutthrough_connection("incompatible connection");
+  cancel_cutthrough_connection(TRUE, US"incompatible connection");
 return done;
 }
 
@@ -490,6 +490,7 @@ Arguments:
                       vopt_callout_random => do the "random" thing
                       vopt_callout_recipsender => use real sender for recipient
                       vopt_callout_recippmaster => use postmaster for recipient
+                     vopt_callout_hold         => lazy close connection
   se_mailfrom         MAIL FROM address for sender verify; NULL => ""
   pm_mailfrom         if non-NULL, do the postmaster check with this sender
 
@@ -556,7 +557,10 @@ else
 if (cached_callout_lookup(addr, address_key, from_address,
       &options, &pm_mailfrom, &yield, failure_ptr,
       &new_domain_record, &old_domain_cache_result))
+  {
+  cancel_cutthrough_connection(TRUE, US"cache-hit");
   goto END_CALLOUT;
+  }
 
 if (!addr->transport)
   {
@@ -756,9 +760,12 @@ tls_retry_connection:
        }
 #endif
 
-      /* This would be ok for 1st rcpt of a cutthrough (XXX do we have a count?) , but no way to
-      handle a subsequent because of the RSET.  So refuse to support any. */
-      cancel_cutthrough_connection("random-recipient");
+      /* This would be ok for 1st rcpt of a cutthrough (the case handled here;
+      subsequents are done in cutthrough_multi()), but no way to
+      handle a subsequent because of the RSET vaporising the MAIL FROM.
+      So refuse to support any.  Most cutthrough use will not involve
+      random_local_part, so no loss. */
+      cancel_cutthrough_connection(TRUE, US"random-recipient");
 
       addr->address = string_sprintf("%s@%.1000s",
                                    random_local_part, rcpt_domain);
@@ -887,7 +894,7 @@ tls_retry_connection:
       /* Could possibly shift before main verify, just above, and be ok
       for cutthrough.  But no way to handle a subsequent rcpt, so just
       refuse any */
-      cancel_cutthrough_connection("postmaster verify");
+      cancel_cutthrough_connection(TRUE, US"postmaster verify");
       HDEBUG(D_acl|D_v) debug_printf_indent("Cutthrough cancelled by presence of postmaster verify\n");
 
       done = smtp_write_command(&sx.outblock, FALSE, "RSET\r\n") >= 0
@@ -1003,8 +1010,10 @@ no_conn:
 
     /* Cutthrough - on a successful connect and recipient-verify with
     use-sender and we are 1st rcpt and have no cutthrough conn so far
-    here is where we want to leave the conn open */
-    if (  cutthrough.delivery
+    here is where we want to leave the conn open.  Ditto for a lazy-close
+    verify. */
+
+    if (  (cutthrough.delivery || options & vopt_callout_hold)
        && rcpt_count == 1
        && done
        && yield == OK
@@ -1016,14 +1025,29 @@ no_conn:
        && !sx.lmtp
        )
       {
-      HDEBUG(D_acl|D_v) debug_printf_indent("holding verify callout open for cutthrough delivery\n");
-
-      cutthrough.fd = sx.outblock.sock;        /* We assume no buffer in use in the outblock */
-      cutthrough.nrcpt = 1;
-      cutthrough.interface = interface;
-      cutthrough.host = *host;
-      cutthrough.addr = *addr;         /* Save the address_item for later logging */
-      cutthrough.addr.next =     NULL;
+      HDEBUG(D_acl|D_v) debug_printf_indent("holding verify callout open for %s\n",
+       cutthrough.delivery
+       ? "cutthrough delivery" : "potential further verifies and delivery");
+
+      cutthrough.callout_hold_only = !cutthrough.delivery;
+      cutthrough.is_tls =      tls_out.active >= 0;
+      cutthrough.fd =  sx.outblock.sock;       /* We assume no buffer in use in the outblock */
+      cutthrough.nrcpt =       1;
+      cutthrough.transport =   addr->transport->name;
+      cutthrough.interface =   interface;
+      cutthrough.snd_port =    sending_port;
+      cutthrough.peer_options =        smtp_peer_options;
+      cutthrough.host =                *host;
+       {
+       int oldpool = store_pool;
+       store_pool = POOL_PERM;
+       cutthrough.snd_ip = string_copy(sending_ip_address);
+       cutthrough.host.name = string_copy(host->name);
+       cutthrough.host.address = string_copy(host->address);
+       store_pool = oldpool;
+       }
+      cutthrough.addr =                *addr;          /* Save the address_item for later logging */
+      cutthrough.addr.next =   NULL;
       cutthrough.addr.host_used = &cutthrough.host;
       if (addr->parent)
         *(cutthrough.addr.parent = store_get(sizeof(address_item))) =
@@ -1036,9 +1060,9 @@ no_conn:
       }
     else
       {
-      /* Ensure no cutthrough on multiple address verifies */
+      /* Ensure no cutthrough on multiple verifies that were incompatible */
       if (options & vopt_callout_recipsender)
-        cancel_cutthrough_connection("not usable for cutthrough");
+        cancel_cutthrough_connection(TRUE, US"not usable for cutthrough");
       if (sx.send_quit)
        {
        (void) smtp_write_command(&sx.outblock, FALSE, "QUIT\r\n");
@@ -1184,20 +1208,26 @@ return TRUE;
 }
 
 /* Buffered output of counted data block.   Return boolean success */
-BOOL
+static BOOL
 cutthrough_puts(uschar * cp, int n)
 {
 if (cutthrough.fd < 0)       return TRUE;
 if (_cutthrough_puts(cp, n)) return TRUE;
-cancel_cutthrough_connection("transmit failed");
+cancel_cutthrough_connection(TRUE, US"transmit failed");
 return FALSE;
 }
 
+BOOL
+cutthrough_data_puts(uschar * cp, int n)
+{
+if (cutthrough.delivery) cutthrough_puts(cp, n);
+}
+
 
 static BOOL
 _cutthrough_flush_send(void)
 {
-int n= ctblock.ptr-ctblock.buffer;
+int n = ctblock.ptr - ctblock.buffer;
 
 if(n>0)
   if(!cutthrough_send(n))
@@ -1211,21 +1241,28 @@ BOOL
 cutthrough_flush_send(void)
 {
 if (_cutthrough_flush_send()) return TRUE;
-cancel_cutthrough_connection("transmit failed");
+cancel_cutthrough_connection(TRUE, US"transmit failed");
 return FALSE;
 }
 
 
-BOOL
+static BOOL
 cutthrough_put_nl(void)
 {
 return cutthrough_puts(US"\r\n", 2);
 }
 
 
+BOOL
+cutthrough_data_put_nl(void)
+{
+return cutthrough_data_puts(US"\r\n", 2);
+}
+
+
 /* Get and check response from cutthrough target */
 static uschar
-cutthrough_response(char expect, uschar ** copy, int timeout)
+cutthrough_response(int fd, char expect, uschar ** copy, int timeout)
 {
 smtp_inblock inblock;
 uschar inbuffer[4096];
@@ -1235,12 +1272,12 @@ inblock.buffer = inbuffer;
 inblock.buffersize = sizeof(inbuffer);
 inblock.ptr = inbuffer;
 inblock.ptrend = inbuffer;
-inblock.sock = cutthrough.fd;
+inblock.sock = fd;
 /* this relies on (inblock.sock == tls_out.active) */
 if(!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), expect, timeout))
-  cancel_cutthrough_connection("target timeout on read");
+  cancel_cutthrough_connection(TRUE, US"target timeout on read");
 
-if(copy != NULL)
+if(copy)
   {
   uschar * cp;
   *copy = cp = string_copy(responsebuffer);
@@ -1258,7 +1295,7 @@ return responsebuffer[0];
 BOOL
 cutthrough_predata(void)
 {
-if(cutthrough.fd < 0)
+if(cutthrough.fd < 0 || cutthrough.callout_hold_only)
   return FALSE;
 
 HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP>> DATA\n");
@@ -1266,7 +1303,7 @@ cutthrough_puts(US"DATA\r\n", 6);
 cutthrough_flush_send();
 
 /* Assume nothing buffered.  If it was it gets ignored. */
-return cutthrough_response('3', NULL, CUTTHROUGH_DATA_TIMEOUT) == '3';
+return cutthrough_response(cutthrough.fd, '3', NULL, CUTTHROUGH_DATA_TIMEOUT) == '3';
 }
 
 
@@ -1293,7 +1330,7 @@ cutthrough_headers_send(void)
 {
 transport_ctx tctx;
 
-if(cutthrough.fd < 0)
+if(cutthrough.fd < 0 || cutthrough.callout_hold_only)
   return FALSE;
 
 /* We share a routine with the mainline transport to handle header add/remove/rewrites,
@@ -1318,7 +1355,8 @@ return TRUE;
 static void
 close_cutthrough_connection(const char * why)
 {
-if(cutthrough.fd >= 0)
+int fd = cutthrough.fd;
+if(fd >= 0)
   {
   /* We could be sending this after a bunch of data, but that is ok as
      the only way to cancel the transfer in dataphase is to drop the tcp
@@ -1328,26 +1366,36 @@ if(cutthrough.fd >= 0)
   HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP>> QUIT\n");
   _cutthrough_puts(US"QUIT\r\n", 6);   /* avoid recursion */
   _cutthrough_flush_send();
+  cutthrough.fd = -1;                  /* avoid recursion via read timeout */
 
   /* Wait a short time for response, and discard it */
-  cutthrough_response('2', NULL, 1);
+  cutthrough_response(fd, '2', NULL, 1);
 
-  #ifdef SUPPORT_TLS
+#ifdef SUPPORT_TLS
   tls_close(FALSE, TRUE);
-  #endif
+#endif
   HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP(close)>>\n");
-  (void)close(cutthrough.fd);
-  cutthrough.fd = -1;
+  (void)close(fd);
   HDEBUG(D_acl) debug_printf_indent("----------- cutthrough shutdown (%s) ------------\n", why);
   }
 ctblock.ptr = ctbuffer;
 }
 
 void
-cancel_cutthrough_connection(const char * why)
+cancel_cutthrough_connection(BOOL close_noncutthrough_verifies, const uschar * why)
+{
+if (cutthrough.delivery || close_noncutthrough_verifies)
+  close_cutthrough_connection(why);
+cutthrough.delivery = cutthrough.callout_hold_only = FALSE;
+}
+
+
+void
+release_cutthrough_connection(const uschar * why)
 {
-close_cutthrough_connection(why);
-cutthrough.delivery = FALSE;
+HDEBUG(D_acl) debug_printf_indent("release cutthrough conn: %s\n", why);
+cutthrough.fd = -1;
+cutthrough.delivery = cutthrough.callout_hold_only = FALSE;
 }
 
 
@@ -1372,7 +1420,7 @@ if(  !cutthrough_puts(US".", 1)
   )
   return cutthrough.addr.message;
 
-res = cutthrough_response('2', &cutthrough.addr.message, CUTTHROUGH_DATA_TIMEOUT);
+res = cutthrough_response(cutthrough.fd, '2', &cutthrough.addr.message, CUTTHROUGH_DATA_TIMEOUT);
 for (addr = &cutthrough.addr; addr; addr = addr->next)
   {
   addr->message = cutthrough.addr.message;
@@ -1879,7 +1927,7 @@ while (addr_new)
         }
       respond_printf(f, "%s\n", cr);
       }
-    cancel_cutthrough_connection("routing hard fail");
+    cancel_cutthrough_connection(TRUE, US"routing hard fail");
 
     if (!full_info)
       {
@@ -1918,7 +1966,7 @@ while (addr_new)
         }
       respond_printf(f, "%s\n", cr);
       }
-    cancel_cutthrough_connection("routing soft fail");
+    cancel_cutthrough_connection(TRUE, US"routing soft fail");
 
     if (!full_info)
       {
@@ -1991,7 +2039,7 @@ while (addr_new)
       /* If stopped because more than one new address, cannot cutthrough */
 
       if (addr_new && addr_new->next)
-       cancel_cutthrough_connection("multiple addresses from routing");
+       cancel_cutthrough_connection(TRUE, US"multiple addresses from routing");
 
       yield = OK;
       goto out;
@@ -2241,18 +2289,16 @@ verify_check_header_names_ascii(uschar **msgptr)
 header_line *h;
 uschar *colon, *s;
 
-for (h = header_list; h != NULL; h = h->next)
+for (h = header_list; h; h = h->next)
   {
-   colon = Ustrchr(h->text, ':');
-   for(s = h->text; s < colon; s++)
-     {
-        if ((*s < 33) || (*s > 126))
-        {
-                *msgptr = string_sprintf("Invalid character in header \"%.*s\" found",
-                                         colon - h->text, h->text);
-                return FAIL;
-        }
-     }
+  colon = Ustrchr(h->text, ':');
+  for(s = h->text; s < colon; s++)
+    if ((*s < 33) || (*s > 126))
+      {
+      *msgptr = string_sprintf("Invalid character in header \"%.*s\" found",
+                            colon - h->text, h->text);
+      return FAIL;
+      }
   }
 return OK;
 }