DANE: if all TLSA records are unusable, retry verification non-dane.
[exim.git] / src / src / verify.c
index 911d67227ecfcce5f3ad79925836a5e5d823b12f..a22bb7d5b5172f6c506e25d4c5f15ce82a971def 100644 (file)
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) University of Cambridge 1995 - 2009 */
+/* Copyright (c) University of Cambridge 1995 - 2014 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Functions concerned with verifying things. The original code for callout
@@ -14,7 +14,6 @@ caching was contributed by Kevin Fleming (but I hacked it around a bit). */
 
 #define CUTTHROUGH_CMD_TIMEOUT  30     /* timeout for cutthrough-routing calls */
 #define CUTTHROUGH_DATA_TIMEOUT 60     /* timeout for cutthrough-routing calls */
-address_item cutthrough_addr;
 static smtp_outblock ctblock;
 uschar ctbuffer[8192];
 
@@ -39,6 +38,7 @@ static tree_node *dnsbl_cache = NULL;
 #define MT_NOT 1
 #define MT_ALL 2
 
+static uschar cutthrough_response(char, uschar **);
 
 
 /*************************************************
@@ -189,12 +189,12 @@ from_address = US"";
 
 if (is_recipient)
   {
-  if ((options & vopt_callout_recipsender) != 0)
+  if (options & vopt_callout_recipsender)
     {
     address_key = string_sprintf("%s/<%s>", addr->address, sender_address);
     from_address = sender_address;
     }
-  else if ((options & vopt_callout_recippmaster) != 0)
+  else if (options & vopt_callout_recippmaster)
     {
     address_key = string_sprintf("%s/<postmaster@%s>", addr->address,
       qualify_domain_sender);
@@ -373,10 +373,13 @@ if (!addr->transport)
   {
   HDEBUG(D_verify) debug_printf("cannot callout via null transport\n");
   }
+else if (Ustrcmp(addr->transport->driver_name, "smtp") != 0)
+  log_write(0, LOG_MAIN|LOG_PANIC|LOG_CONFIG_FOR, "callout transport '%s': %s is non-smtp",
+    addr->transport->name, addr->transport->driver_name);
 else
   {
   smtp_transport_options_block *ob =
-    (smtp_transport_options_block *)(addr->transport->options_block);
+    (smtp_transport_options_block *)addr->transport->options_block;
 
   /* The information wasn't available in the cache, so we have to do a real
   callout and save the result in the cache for next time, unless no_cache is set,
@@ -407,6 +410,113 @@ else
 
   if (smtp_out != NULL && !disable_callout_flush) mac_smtp_fflush();
 
+/* cutthrough-multi: if a nonfirst rcpt has the same routing as the first,
+and we are holding a cutthrough conn open, we can just append the rcpt to
+that conn for verification purposes (and later delivery also).  Simplest
+coding means skipping this whole loop and doing the append separately.
+
+We will need to remember it has been appended so that rcpt-acl tail code
+can do it there for the non-rcpt-verify case.  For this we keep an addresscount.
+*/
+
+  /* Can we re-use an open cutthrough connection? */
+  if (  cutthrough.fd >= 0
+     && (options & (vopt_callout_recipsender | vopt_callout_recippmaster))
+       == vopt_callout_recipsender
+     && !random_local_part
+     && !pm_mailfrom
+     )
+    {
+    if (addr->transport == cutthrough.addr.transport)
+      for (host = host_list; host; host = host->next)
+       if (Ustrcmp(host->address, cutthrough.host.address) == 0)
+         {
+         int host_af;
+         uschar *interface = NULL;  /* Outgoing interface to use; NULL => any */
+         int port = 25;
+
+         deliver_host = host->name;
+         deliver_host_address = host->address;
+         deliver_host_port = host->port;
+         deliver_domain = addr->domain;
+         transport_name = addr->transport->name;
+
+         host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
+
+         if (!smtp_get_interface(tf->interface, host_af, addr, NULL, &interface,
+                 US"callout") ||
+             !smtp_get_port(tf->port, addr, &port, US"callout"))
+           log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
+             addr->message);
+
+         if (  (  interface == cutthrough.interface
+               || (  interface
+                  && cutthrough.interface
+                  && Ustrcmp(interface, cutthrough.interface) == 0
+               )  )
+            && port == cutthrough.host.port
+            )
+           {
+           uschar * resp;
+
+           /* Match!  Send the RCPT TO, append the addr, set done */
+           done =
+             smtp_write_command(&ctblock, FALSE, "RCPT TO:<%.1000s>\r\n",
+               transport_rcpt_address(addr,
+                 (addr->transport == NULL)? FALSE :
+                  addr->transport->rcpt_include_affixes)) >= 0 &&
+             cutthrough_response('2', &resp) == '2';
+
+           /* This would go horribly wrong if a callout fail was ignored by ACL.
+           We punt by abandoning cutthrough on a reject, like the
+           first-rcpt does. */
+
+           if (done)
+             {
+             address_item * na = store_get(sizeof(address_item));
+             *na = cutthrough.addr;
+             cutthrough.addr = *addr;
+             cutthrough.addr.host_used = &cutthrough.host;
+             cutthrough.addr.next = na;
+
+             cutthrough.nrcpt++;
+             }
+           else
+             {
+             cancel_cutthrough_connection("recipient rejected");
+             if (errno == ETIMEDOUT)
+               {
+               HDEBUG(D_verify) debug_printf("SMTP timeout\n");
+               }
+             else if (errno == 0)
+               {
+               if (*resp == 0)
+                 Ustrcpy(resp, US"connection dropped");
+
+               addr->message =
+                 string_sprintf("response to \"%s\" from %s [%s] was: %s",
+                   big_buffer, host->name, host->address,
+                   string_printing(resp));
+
+               addr->user_message =
+                 string_sprintf("Callout verification failed:\n%s", resp);
+
+               /* Hard rejection ends the process */
+
+               if (resp[0] == '5')   /* Address rejected */
+                 {
+                 yield = FAIL;
+                 done = TRUE;
+                 }
+               }
+             }
+           }
+         break;
+         }
+    if (!done)
+      cancel_cutthrough_connection("incompatible connection");
+    }
+
   /* Now make connections to the hosts and do real callouts. The list of hosts
   is passed in as an argument. */
 
@@ -423,6 +533,11 @@ else
     BOOL esmtp;
     BOOL suppress_tls = FALSE;
     uschar *interface = NULL;  /* Outgoing interface to use; NULL => any */
+#if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
+    BOOL dane = FALSE;
+    BOOL dane_required;
+    dns_answer tlsa_dnsa;
+#endif
     uschar inbuffer[4096];
     uschar outbuffer[1024];
     uschar responsebuffer[4096];
@@ -459,7 +574,9 @@ else
 
     deliver_host = host->name;
     deliver_host_address = host->address;
+    deliver_host_port = host->port;
     deliver_domain = addr->domain;
+    transport_name = addr->transport->name;
 
     if (!smtp_get_interface(tf->interface, host_af, addr, NULL, &interface,
             US"callout") ||
@@ -474,6 +591,35 @@ else
 
     HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", interface, port);
 
+#if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_DANE)
+      {
+      int rc;
+
+      tls_out.dane_verified = FALSE;
+      tls_out.tlsa_usage = 0;
+
+      dane_required =
+       verify_check_given_host(&ob->hosts_require_dane, host) == OK;
+
+      if (host->dnssec == DS_YES)
+       {
+       if(  dane_required
+         || verify_check_given_host(&ob->hosts_try_dane, host) == OK
+         )
+         if ((rc = tlsa_lookup(host, &tlsa_dnsa, dane_required, &dane)) != OK)
+           return rc;
+       }
+      else if (dane_required)
+       {
+       log_write(0, LOG_MAIN, "DANE error: %s lookup not DNSSEC", host->name);
+       return FAIL;
+       }
+
+      if (dane)
+       ob->tls_tempfail_tryclear = FALSE;
+      }
+#endif  /*DANE*/
+
     /* Set up the buffer for reading SMTP response packets. */
 
     inblock.buffer = inbuffer;
@@ -498,12 +644,18 @@ else
     tls_retry_connection:
 
     inblock.sock = outblock.sock =
-      smtp_connect(host, host_af, port, interface, callout_connect, TRUE, NULL);
+      smtp_connect(host, host_af, port, interface, callout_connect, TRUE, NULL
+#ifdef EXPERIMENTAL_EVENT
+    /*XXX event action? NULL for now. */
+                 , NULL
+#endif
+                 );
     /* reconsider DSCP here */
     if (inblock.sock < 0)
       {
       addr->message = string_sprintf("could not connect to %s [%s]: %s",
           host->name, host->address, strerror(errno));
+      transport_name = NULL;
       deliver_host = deliver_host_address = NULL;
       deliver_domain = save_deliver_domain;
       continue;
@@ -521,9 +673,6 @@ else
       else active_hostname = s;
       }
 
-    deliver_host = deliver_host_address = NULL;
-    deliver_domain = save_deliver_domain;
-
     /* Wait for initial response, and send HELO. The smtp_write_command()
     function leaves its command in big_buffer. This is used in error responses.
     Initialize it in case the connection is rejected. */
@@ -533,28 +682,42 @@ else
     /* Unless ssl-on-connect, wait for the initial greeting */
     smtps_redo_greeting:
 
-    #ifdef SUPPORT_TLS
+#ifdef SUPPORT_TLS
     if (!smtps || (smtps && tls_out.active >= 0))
-    #endif
+#endif
+      {
       if (!(done= smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout)))
         goto RESPONSE_FAILED;
-    
+
+#ifdef EXPERIMENTAL_EVENT
+      lookup_dnssec_authenticated = host->dnssec==DS_YES ? US"yes"
+       : host->dnssec==DS_NO ? US"no" : NULL;
+      if (event_raise(addr->transport->event_action,
+                           US"smtp:connect", responsebuffer))
+       {
+       lookup_dnssec_authenticated = NULL;
+       /* Logging?  Debug? */
+       goto RESPONSE_FAILED;
+       }
+      lookup_dnssec_authenticated = NULL;
+#endif
+      }
+
     /* Not worth checking greeting line for ESMTP support */
-    if (!(esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL,
-      host->name, host->address, NULL) != OK))
+    if (!(esmtp = verify_check_given_host(&(ob->hosts_avoid_esmtp), host) != OK))
       DEBUG(D_transport)
         debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n");
 
     tls_redo_helo:
 
-    #ifdef SUPPORT_TLS
+#ifdef SUPPORT_TLS
     if (smtps  &&  tls_out.active < 0) /* ssl-on-connect, first pass */
       {
       tls_offered = TRUE;
       ob->tls_tempfail_tryclear = FALSE;
       }
-      else                             /* all other cases */
-    #endif
+    else                               /* all other cases */
+#endif
 
       { esmtp_retry:
 
@@ -568,26 +731,26 @@ else
          done= FALSE;
          goto RESPONSE_FAILED;
          }
-        #ifdef SUPPORT_TLS
+#ifdef SUPPORT_TLS
         tls_offered = FALSE;
-        #endif
+#endif
         esmtp = FALSE;
         goto esmtp_retry;                      /* fallback to HELO */
         }
 
       /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */
-      #ifdef SUPPORT_TLS
+#ifdef SUPPORT_TLS
       if (esmtp && !suppress_tls &&  tls_out.active < 0)
-        {
-          if (regex_STARTTLS == NULL) regex_STARTTLS =
-           regex_must_compile(US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE, TRUE);
+       {
+       if (regex_STARTTLS == NULL) regex_STARTTLS =
+         regex_must_compile(US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE, TRUE);
 
-          tls_offered = pcre_exec(regex_STARTTLS, NULL, CS responsebuffer,
-                       Ustrlen(responsebuffer), 0, PCRE_EOPT, NULL, 0) >= 0;
+       tls_offered = pcre_exec(regex_STARTTLS, NULL, CS responsebuffer,
+                     Ustrlen(responsebuffer), 0, PCRE_EOPT, NULL, 0) >= 0;
        }
       else
         tls_offered = FALSE;
-      #endif
+#endif
       }
 
     /* If TLS is available on this connection attempt to
@@ -598,12 +761,10 @@ else
     the client not be required to use TLS. If the response is bad, copy the buffer
     for error analysis. */
 
-    #ifdef SUPPORT_TLS
-    if (tls_offered &&
-       verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name,
-         host->address, NULL) != OK &&
-       verify_check_this_host(&(ob->hosts_verify_avoid_tls), NULL, host->name,
-         host->address, NULL) != OK
+#ifdef SUPPORT_TLS
+    if (  tls_offered
+       && verify_check_given_host(&ob->hosts_avoid_tls, host) != OK
+       && verify_check_given_host(&ob->hosts_verify_avoid_tls, host) != OK
        )
       {
       uschar buffer2[4096];
@@ -623,46 +784,72 @@ else
         {
         if (errno != 0 || buffer2[0] == 0 ||
                (buffer2[0] == '4' && !ob->tls_tempfail_tryclear))
-       {
-       Ustrncpy(responsebuffer, buffer2, sizeof(responsebuffer));
-       done= FALSE;
-       goto RESPONSE_FAILED;
-       }
+         {
+         Ustrncpy(responsebuffer, buffer2, sizeof(responsebuffer));
+         done= FALSE;
+         goto RESPONSE_FAILED;
+         }
         }
 
        /* STARTTLS accepted or ssl-on-connect: try to negotiate a TLS session. */
       else
         {
-        int rc = tls_client_start(inblock.sock, host, addr,
-        ob->tls_certificate, ob->tls_privatekey,
-        ob->tls_sni,
-        ob->tls_verify_certificates, ob->tls_crl,
-        ob->tls_require_ciphers,
-#ifdef EXPERIMENTAL_OCSP
-        ob->hosts_require_ocsp,
-#endif
-        ob->tls_dh_min_bits,         callout);
-
-        /* TLS negotiation failed; give an error.  Try in clear on a new connection,
-           if the options permit it for this host. */
+       int oldtimeout = ob->command_timeout;
+       int rc;
+
+       tls_negotiate:
+       ob->command_timeout = callout;
+        rc = tls_client_start(inblock.sock, host, addr, addr->transport
+# ifdef EXPERIMENTAL_DANE
+                           , dane ? &tlsa_dnsa : NULL
+# endif
+                           );
+       ob->command_timeout = oldtimeout;
+
+        /* TLS negotiation failed; give an error.  Try in clear on a new
+       connection, if the options permit it for this host. */
         if (rc != OK)
           {
-       if (rc == DEFER && ob->tls_tempfail_tryclear && !smtps &&
-          verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
-            host->address, NULL) != OK)
-         {
-            (void)close(inblock.sock);
-         log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
-           "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
-         suppress_tls = TRUE;
-         goto tls_retry_connection;
-         }
-       /*save_errno = ERRNO_TLSFAILURE;*/
-       /*message = US"failure while setting up TLS session";*/
-       send_quit = FALSE;
-       done= FALSE;
-       goto TLS_FAILED;
-       }
+         if (rc == DEFER)
+           {
+           (void)close(inblock.sock);
+# ifdef EXPERIMENTAL_EVENT
+           (void) event_raise(addr->transport->event_action,
+                                   US"tcp:close", NULL);
+# endif
+# ifdef EXPERIMENTAL_DANE
+           if (dane)
+             {
+             if (!dane_required)
+               {
+               log_write(0, LOG_MAIN, "DANE attempt failed;"
+                 " trying CA-root TLS to %s [%s] (not in hosts_require_dane)",
+                 host->name, host->address);
+               dane = FALSE;
+               goto tls_negotiate;
+               }
+             }
+           else
+# endif
+             if (  ob->tls_tempfail_tryclear
+                && !smtps
+                && verify_check_given_host(&ob->hosts_require_tls, host) != OK
+                )
+             {
+             log_write(0, LOG_MAIN, "TLS session failure:"
+               " delivering unencrypted to %s [%s] (not in hosts_require_tls)",
+               host->name, host->address);
+             suppress_tls = TRUE;
+             goto tls_retry_connection;
+             }
+           }
+
+         /*save_errno = ERRNO_TLSFAILURE;*/
+         /*message = US"failure while setting up TLS session";*/
+         send_quit = FALSE;
+         done= FALSE;
+         goto TLS_FAILED;
+         }
 
         /* TLS session is set up.  Copy info for logging. */
         addr->cipher = tls_out.cipher;
@@ -670,7 +857,7 @@ else
 
         /* For SMTPS we need to wait for the initial OK response, then do HELO. */
         if (smtps)
-        goto smtps_redo_greeting;
+         goto smtps_redo_greeting;
 
         /* For STARTTLS we need to redo EHLO */
         goto tls_redo_helo;
@@ -679,18 +866,24 @@ else
 
     /* If the host is required to use a secure channel, ensure that we have one. */
     if (tls_out.active < 0)
-      if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name,
-       host->address, NULL) == OK)
+      if (
+# ifdef EXPERIMENTAL_DANE
+        dane ||
+# endif
+         verify_check_given_host(&ob->hosts_require_tls, host) == OK
+        )
         {
         /*save_errno = ERRNO_TLSREQUIRED;*/
-        log_write(0, LOG_MAIN, "a TLS session is required for %s [%s], but %s",
+        log_write(0, LOG_MAIN,
+         "H=%s [%s]: a TLS session is required for this host, but %s",
           host->name, host->address,
-       tls_offered? "an attempt to start TLS failed" : "the server did not offer TLS support");
+         tls_offered ? "an attempt to start TLS failed"
+                     : "the server did not offer TLS support");
         done= FALSE;
         goto TLS_FAILED;
         }
 
-    #endif /*SUPPORT_TLS*/
+#endif /*SUPPORT_TLS*/
 
     done = TRUE; /* so far so good; have response to HELO */
 
@@ -698,10 +891,20 @@ else
 
     /* For now, transport_filter by cutthrough-delivery is not supported */
     /* Need proper integration with the proper transport mechanism. */
-    if (cutthrough_delivery && addr->transport->filter_command)
+    if (cutthrough.delivery)
       {
-      cutthrough_delivery= FALSE;
-      HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of transport filter\n");
+      if (addr->transport->filter_command)
+        {
+        cutthrough.delivery = FALSE;
+        HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of transport filter\n");
+        }
+#ifndef DISABLE_DKIM
+      if (ob->dkim_domain)
+        {
+        cutthrough.delivery = FALSE;
+        HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of DKIM signing\n");
+        }
+#endif
       }
 
     SEND_FAILED:
@@ -710,7 +913,6 @@ else
     ;
     /* Clear down of the TLS, SMTP and TCP layers on error is handled below.  */
 
-
     /* Failure to accept HELO is cached; this blocks the whole domain for all
     senders. I/O errors and defer responses are not cached. */
 
@@ -748,6 +950,9 @@ else
       smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
         '2', callout);
 
+    deliver_host = deliver_host_address = NULL;
+    deliver_domain = save_deliver_domain;
+
     /* If the host does not accept MAIL FROM:<>, arrange to cache this
     information, but again, don't record anything for an I/O error or a defer. Do
     not cache rejections of MAIL when a non-empty sender has been used, because
@@ -800,9 +1005,7 @@ else
         /* If accepted, we aren't going to do any further tests below. */
 
         if (random_ok)
-          {
           new_domain_record.random_result = ccache_accept;
-          }
 
         /* Otherwise, cache a real negative response, and get back to the right
         state to send RCPT. Unless there's some problem such as a dropped
@@ -810,6 +1013,8 @@ else
 
         else if (errno == 0)
           {
+         cancel_cutthrough_connection("random-recipient");
+
           if (randombuffer[0] == '5')
             new_domain_record.random_result = ccache_reject;
 
@@ -855,8 +1060,9 @@ else
 
         if (done && pm_mailfrom != NULL)
           {
-          /*XXX not suitable for cutthrough - sequencing problems */
-       cutthrough_delivery= FALSE;
+          /*XXX not suitable for cutthrough - we cannot afford to do an RSET
+         and lose the original mail-from */
+       cancel_cutthrough_connection("postmaster verify");
        HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of postmaster verify\n");
 
           done =
@@ -951,31 +1157,35 @@ else
 
     /* End the SMTP conversation and close the connection. */
 
-    /* Cutthrough - on a successfull connect and recipient-verify with use-sender
-    and we have no cutthrough conn so far
+    /* Cutthrough - on a successfull 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
+    if (  cutthrough.delivery
+       && rcpt_count == 1
        && done
        && yield == OK
        && (options & (vopt_callout_recipsender|vopt_callout_recippmaster)) == vopt_callout_recipsender
        && !random_local_part
        && !pm_mailfrom
-       && cutthrough_fd < 0
+       && cutthrough.fd < 0
+       && !lmtp
        )
       {
-      cutthrough_fd= outblock.sock;    /* We assume no buffer in use in the outblock */
-      cutthrough_addr = *addr;         /* Save the address_item for later logging */
-      cutthrough_addr.host_used = store_get(sizeof(host_item));
-      cutthrough_addr.host_used->name =    host->name;
-      cutthrough_addr.host_used->address = host->address;
-      cutthrough_addr.host_used->port =    port;
+      cutthrough.fd = 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;
+      cutthrough.addr.host_used = &cutthrough.host;
       if (addr->parent)
-        *(cutthrough_addr.parent = store_get(sizeof(address_item)))= *addr->parent;
+        *(cutthrough.addr.parent = store_get(sizeof(address_item))) =
+         *addr->parent;
       ctblock.buffer = ctbuffer;
       ctblock.buffersize = sizeof(ctbuffer);
       ctblock.ptr = ctbuffer;
       /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */
-      ctblock.sock = cutthrough_fd;
+      ctblock.sock = cutthrough.fd;
       }
     else
       {
@@ -984,10 +1194,14 @@ else
         cancel_cutthrough_connection("multiple verify calls");
       if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
 
-      #ifdef SUPPORT_TLS
+#ifdef SUPPORT_TLS
       tls_close(FALSE, TRUE);
-      #endif
+#endif
       (void)close(inblock.sock);
+#ifdef EXPERIMENTAL_EVENT
+      (void) event_raise(addr->transport->event_action,
+                             US"tcp:close", NULL);
+#endif
       }
 
     }    /* Loop through all hosts, while !done */
@@ -1096,7 +1310,8 @@ address_item addr2;
 get rewritten. */
 
 addr2 = *addr;
-HDEBUG(D_acl) debug_printf("----------- start cutthrough setup ------------\n");
+HDEBUG(D_acl) debug_printf("----------- %s cutthrough setup ------------\n",
+  rcpt_count > 1 ? "more" : "start");
 (void) verify_address(&addr2, NULL,
        vopt_is_recipient | vopt_callout_recipsender | vopt_callout_no_cache,
        CUTTHROUGH_CMD_TIMEOUT, -1, -1,
@@ -1111,14 +1326,14 @@ return;
 static BOOL
 cutthrough_send(int n)
 {
-if(cutthrough_fd < 0)
+if(cutthrough.fd < 0)
   return TRUE;
 
 if(
 #ifdef SUPPORT_TLS
-   (tls_out.active == cutthrough_fd) ? tls_write(FALSE, ctblock.buffer, n) :
+   (tls_out.active == cutthrough.fd) ? tls_write(FALSE, ctblock.buffer, n) :
 #endif
-   send(cutthrough_fd, ctblock.buffer, n, 0) > 0
+   send(cutthrough.fd, ctblock.buffer, n, 0) > 0
   )
 {
   transport_count += n;
@@ -1150,7 +1365,7 @@ return TRUE;
 BOOL
 cutthrough_puts(uschar * cp, int n)
 {
-if (cutthrough_fd < 0)       return TRUE;
+if (cutthrough.fd < 0)       return TRUE;
 if (_cutthrough_puts(cp, n)) return TRUE;
 cancel_cutthrough_connection("transmit failed");
 return FALSE;
@@ -1158,7 +1373,7 @@ return FALSE;
 
 
 static BOOL
-_cutthrough_flush_send( void )
+_cutthrough_flush_send(void)
 {
 int n= ctblock.ptr-ctblock.buffer;
 
@@ -1171,7 +1386,7 @@ return TRUE;
 
 /* Send out any bufferred output.  Return boolean success. */
 BOOL
-cutthrough_flush_send( void )
+cutthrough_flush_send(void)
 {
 if (_cutthrough_flush_send()) return TRUE;
 cancel_cutthrough_connection("transmit failed");
@@ -1180,7 +1395,7 @@ return FALSE;
 
 
 BOOL
-cutthrough_put_nl( void )
+cutthrough_put_nl(void)
 {
 return cutthrough_puts(US"\r\n", 2);
 }
@@ -1198,7 +1413,7 @@ inblock.buffer = inbuffer;
 inblock.buffersize = sizeof(inbuffer);
 inblock.ptr = inbuffer;
 inblock.ptrend = inbuffer;
-inblock.sock = cutthrough_fd;
+inblock.sock = cutthrough.fd;
 /* this relies on (inblock.sock == tls_out.active) */
 if(!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), expect, CUTTHROUGH_DATA_TIMEOUT))
   cancel_cutthrough_connection("target timeout on read");
@@ -1206,7 +1421,7 @@ if(!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), expect,
 if(copy != NULL)
   {
   uschar * cp;
-  *copy= cp= string_copy(responsebuffer);
+  *copy = cp = string_copy(responsebuffer);
   /* Trim the trailing end of line */
   cp += Ustrlen(responsebuffer);
   if(cp > *copy  &&  cp[-1] == '\n') *--cp = '\0';
@@ -1219,9 +1434,9 @@ return responsebuffer[0];
 
 /* Negotiate dataphase with the cutthrough target, returning success boolean */
 BOOL
-cutthrough_predata( void )
+cutthrough_predata(void)
 {
-if(cutthrough_fd < 0)
+if(cutthrough.fd < 0)
   return FALSE;
 
 HDEBUG(D_transport|D_acl|D_v) debug_printf("  SMTP>> DATA\n");
@@ -1233,34 +1448,52 @@ return cutthrough_response('3', NULL) == '3';
 }
 
 
+/* fd and use_crlf args only to match write_chunk() */
+static BOOL
+cutthrough_write_chunk(int fd, uschar * s, int len, BOOL use_crlf)
+{
+uschar * s2;
+while(s && (s2 = Ustrchr(s, '\n')))
+ {
+ if(!cutthrough_puts(s, s2-s) || !cutthrough_put_nl())
+  return FALSE;
+ s = s2+1;
+ }
+return TRUE;
+}
+
+
 /* Buffered send of headers.  Return success boolean. */
 /* Expands newlines to wire format (CR,NL).           */
 /* Also sends header-terminating blank line.          */
 BOOL
-cutthrough_headers_send( void )
+cutthrough_headers_send(void)
 {
-header_line * h;
-uschar * cp1, * cp2;
-
-if(cutthrough_fd < 0)
+if(cutthrough.fd < 0)
   return FALSE;
 
-for(h= header_list; h != NULL; h= h->next)
-  if(h->type != htype_old  &&  h->text != NULL)
-    for (cp1 = h->text; *cp1 && (cp2 = Ustrchr(cp1, '\n')); cp1 = cp2+1)
-      if(  !cutthrough_puts(cp1, cp2-cp1)
-        || !cutthrough_put_nl())
-        return FALSE;
+/* We share a routine with the mainline transport to handle header add/remove/rewrites,
+   but having a separate buffered-output function (for now)
+*/
+HDEBUG(D_acl) debug_printf("----------- start cutthrough headers send -----------\n");
+
+if (!transport_headers_send(&cutthrough.addr, cutthrough.fd,
+       cutthrough.addr.transport->add_headers,
+       cutthrough.addr.transport->remove_headers,
+       &cutthrough_write_chunk, TRUE,
+       cutthrough.addr.transport->rewrite_rules,
+       cutthrough.addr.transport->rewrite_existflags))
+  return FALSE;
 
-HDEBUG(D_transport|D_acl|D_v) debug_printf("  SMTP>>(nl)\n");
-return cutthrough_put_nl();
+HDEBUG(D_acl) debug_printf("----------- done cutthrough headers send ------------\n");
+return TRUE;
 }
 
 
 static void
-close_cutthrough_connection( const char * why )
+close_cutthrough_connection(const char * why)
 {
-if(cutthrough_fd >= 0)
+if(cutthrough.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
@@ -1275,18 +1508,18 @@ if(cutthrough_fd >= 0)
   #ifdef SUPPORT_TLS
   tls_close(FALSE, TRUE);
   #endif
-  (void)close(cutthrough_fd);
-  cutthrough_fd= -1;
+  (void)close(cutthrough.fd);
+  cutthrough.fd = -1;
   HDEBUG(D_acl) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why);
   }
 ctblock.ptr = ctbuffer;
 }
 
 void
-cancel_cutthrough_connection( const char * why )
+cancel_cutthrough_connection(const char * why)
 {
 close_cutthrough_connection(why);
-cutthrough_delivery= FALSE;
+cutthrough.delivery = FALSE;
 }
 
 
@@ -1298,33 +1531,45 @@ cutthrough_delivery= FALSE;
    Return smtp response-class digit.
 */
 uschar *
-cutthrough_finaldot( void )
+cutthrough_finaldot(void)
 {
+uschar res;
+address_item * addr;
 HDEBUG(D_transport|D_acl|D_v) debug_printf("  SMTP>> .\n");
 
 /* Assume data finshed with new-line */
-if(!cutthrough_puts(US".", 1) || !cutthrough_put_nl() || !cutthrough_flush_send())
-  return cutthrough_addr.message;
+if(  !cutthrough_puts(US".", 1)
+  || !cutthrough_put_nl()
+  || !cutthrough_flush_send()
+  )
+  return cutthrough.addr.message;
 
-switch(cutthrough_response('2', &cutthrough_addr.message))
+res = cutthrough_response('2', &cutthrough.addr.message);
+for (addr = &cutthrough.addr; addr; addr = addr->next)
   {
-  case '2':
-    delivery_log(LOG_MAIN, &cutthrough_addr, (int)'>', NULL);
-    close_cutthrough_connection("delivered");
-    break;
+  addr->message = cutthrough.addr.message;
+  switch(res)
+    {
+    case '2':
+      delivery_log(LOG_MAIN, addr, (int)'>', NULL);
+      close_cutthrough_connection("delivered");
+      break;
 
-  case '4':
-    delivery_log(LOG_MAIN, &cutthrough_addr, 0, US"tmp-reject from cutthrough after DATA:");
-    break;
+    case '4':
+      delivery_log(LOG_MAIN, addr, 0,
+       US"tmp-reject from cutthrough after DATA:");
+      break;
 
-  case '5':
-    delivery_log(LOG_MAIN|LOG_REJECT, &cutthrough_addr, 0, US"rejected after DATA:");
-    break;
+    case '5':
+      delivery_log(LOG_MAIN|LOG_REJECT, addr, 0,
+       US"rejected after DATA:");
+      break;
 
-  default:
-    break;
+    default:
+      break;
+    }
   }
-  return cutthrough_addr.message;
+return cutthrough.addr.message;
 }
 
 
@@ -1545,13 +1790,7 @@ if (address[0] == 0) return OK;
 they're used in the context of a transport used by verification. Reset them
 at exit from this routine. */
 
-modify_variable(US"tls_bits",                 &tls_out.bits);
-modify_variable(US"tls_certificate_verified", &tls_out.certificate_verified);
-modify_variable(US"tls_cipher",               &tls_out.cipher);
-modify_variable(US"tls_peerdn",               &tls_out.peerdn);
-#if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
-modify_variable(US"tls_sni",                  &tls_out.sni);
-#endif
+tls_modify_variables(&tls_out);
 
 /* Save a copy of the sender address for re-instating if we change it to <>
 while verifying a sender address (a nice bit of self-reference there). */
@@ -1724,8 +1963,20 @@ while (addr_new != NULL)
                   string_is_ip_address(host->name, NULL) != 0)
                 (void)host_find_byname(host, NULL, flags, &canonical_name, TRUE);
               else
+               {
+               uschar * d_request = NULL, * d_require = NULL;
+               if (Ustrcmp(addr->transport->driver_name, "smtp") == 0)
+                 {
+                 smtp_transport_options_block * ob =
+                     (smtp_transport_options_block *)
+                       addr->transport->options_block;
+                 d_request = ob->dnssec_request_domains;
+                 d_require = ob->dnssec_require_domains;
+                 }
+
                 (void)host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
-                  &canonical_name, NULL);
+                 d_request, d_require, &canonical_name, NULL);
+               }
               }
             }
           }
@@ -1748,8 +1999,10 @@ while (addr_new != NULL)
 #ifdef SUPPORT_TLS
          deliver_set_expansions(addr);
 #endif
+         verify_mode = is_recipient ? US"R" : US"S";
           rc = do_callout(addr, host_list, &tf, callout, callout_overall,
             callout_connect, options, se_mailfrom, pm_mailfrom);
+         verify_mode = NULL;
           }
         }
       else
@@ -2010,14 +2263,7 @@ for (addr_list = addr_local, i = 0; i < 2; addr_list = addr_remote, i++)
 the -bv or -bt case). */
 
 out:
-
-modify_variable(US"tls_bits",                 &tls_in.bits);
-modify_variable(US"tls_certificate_verified", &tls_in.certificate_verified);
-modify_variable(US"tls_cipher",               &tls_in.cipher);
-modify_variable(US"tls_peerdn",               &tls_in.peerdn);
-#if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
-modify_variable(US"tls_sni",                  &tls_in.sni);
-#endif
+tls_modify_variables(&tls_in);
 
 return yield;
 }
@@ -2147,6 +2393,41 @@ return yield;
 }
 
 
+/*************************************************
+*      Check header names for 8-bit characters   *
+*************************************************/
+
+/* This function checks for invalid charcters in header names. See
+RFC 5322, 2.2. and RFC 6532, 3.
+
+Arguments:
+  msgptr     where to put an error message
+
+Returns:     OK
+             FAIL
+*/
+
+int
+verify_check_header_names_ascii(uschar **msgptr)
+{
+header_line *h;
+uschar *colon, *s;
+
+for (h = header_list; h != NULL; 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;
+        }
+     }
+  }
+return OK;
+}
 
 /*************************************************
 *          Check for blind recipients            *
@@ -3024,6 +3305,15 @@ return rc;
 
 
 
+/*************************************************
+*      Check the given host item matches a list  *
+*************************************************/
+int
+verify_check_given_host(uschar **listptr, host_item *host)
+{
+return verify_check_this_host(listptr, NULL, host->name, host->address, NULL);
+}
+
 /*************************************************
 *      Check the remote host matches a list      *
 *************************************************/
@@ -3493,7 +3783,7 @@ revadd[0] = 0;
 
 /* In case this is the first time the DNS resolver is being used. */
 
-dns_init(FALSE, FALSE);
+dns_init(FALSE, FALSE, FALSE); /*XXX dnssec? */
 
 /* Loop through all the domains supplied, until something matches */
 
@@ -3664,4 +3954,6 @@ while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL
 return FAIL;
 }
 
+/* vi: aw ai sw=2
+*/
 /* End of verify.c */