Refactor authenticators API to take an (opaque) smtp connection context

[exim.git] / src / src / smtp_out.c

diff --git a/src/src/smtp_out.c b/src/src/smtp_out.c
index c704a0b0f2c9d879aed78602a5b1a6cb47a63a57..6fd0bf72909d3a659d543d6f4d2016a739f04799 100644 (file)
--- a/src/src/smtp_out.c
+++ b/src/src/smtp_out.c
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 

-/* Copyright (c) University of Cambridge 1995 - 2015 */
+/* Copyright (c) University of Cambridge 1995 - 2018 */

 /* See the file NOTICE for conditions of use and distribution. */
 
 /* A number of functions for driving outgoing SMTP calls. */
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* A number of functions for driving outgoing SMTP calls. */


@@ -26,7 +26,6 @@ Arguments:
                which case the function does nothing
   host_af    AF_INET or AF_INET6 for the outgoing IP address
   addr       the mail address being handled (for setting errors)
                which case the function does nothing
   host_af    AF_INET or AF_INET6 for the outgoing IP address
   addr       the mail address being handled (for setting errors)

-  changed    if not NULL, set TRUE if expansion actually changed istring

   interface  point this to the interface
   msg        to add to any error message
 
   interface  point this to the interface
   msg        to add to any error message
 


@@ -36,31 +35,28 @@ Returns:     TRUE on success, FALSE on failure, with error message
 
 BOOL
 smtp_get_interface(uschar *istring, int host_af, address_item *addr,
 
 BOOL
 smtp_get_interface(uschar *istring, int host_af, address_item *addr,

-  BOOL *changed, uschar **interface, uschar *msg)
+  uschar **interface, uschar *msg)

 {
 const uschar * expint;
 uschar *iface;
 int sep = 0;
 
 {
 const uschar * expint;
 uschar *iface;
 int sep = 0;
 

-if (istring == NULL) return TRUE;
+if (!istring) return TRUE;

 
 

-expint = expand_string(istring);
-if (expint == NULL)
+if (!(expint = expand_string(istring)))

   {
   {

-  if (expand_string_forcedfail) return TRUE;
+  if (f.expand_string_forcedfail) return TRUE;

   addr->transport_return = PANIC;
   addr->message = string_sprintf("failed to expand \"interface\" "
       "option for %s: %s", msg, expand_string_message);
   return FALSE;
   }
 
   addr->transport_return = PANIC;
   addr->message = string_sprintf("failed to expand \"interface\" "
       "option for %s: %s", msg, expand_string_message);
   return FALSE;
   }
 

-if (changed != NULL) *changed = expint != istring;
-

 while (isspace(*expint)) expint++;
 if (*expint == 0) return TRUE;
 
 while ((iface = string_nextinlist(&expint, &sep, big_buffer,
 while (isspace(*expint)) expint++;
 if (*expint == 0) return TRUE;
 
 while ((iface = string_nextinlist(&expint, &sep, big_buffer,

-          big_buffer_size)) != NULL)
+          big_buffer_size)))

   {
   if (string_is_ip_address(iface, NULL) == 0)
     {
   {
   if (string_is_ip_address(iface, NULL) == 0)
     {


@@ -75,7 +71,7 @@ while ((iface = string_nextinlist(&expint, &sep, big_buffer,
     break;
   }
 
     break;
   }
 

-if (iface != NULL) *interface = string_copy(iface);
+if (iface) *interface = string_copy(iface);

 return TRUE;
 }
 
 return TRUE;
 }
 


@@ -104,7 +100,7 @@ smtp_get_port(uschar *rstring, address_item *addr, int *port, uschar *msg)
 {
 uschar *pstring = expand_string(rstring);
 
 {
 uschar *pstring = expand_string(rstring);
 

-if (pstring == NULL)
+if (!pstring)

   {
   addr->transport_return = PANIC;
   addr->message = string_sprintf("failed to expand \"%s\" (\"port\" option) "
   {
   addr->transport_return = PANIC;
   addr->message = string_sprintf("failed to expand \"%s\" (\"port\" option) "


@@ -128,7 +124,7 @@ if (isdigit(*pstring))
 else
   {
   struct servent *smtp_service = getservbyname(CS pstring, "tcp");
 else
   {
   struct servent *smtp_service = getservbyname(CS pstring, "tcp");

-  if (smtp_service == NULL)
+  if (!smtp_service)

     {
     addr->transport_return = PANIC;
     addr->message = string_sprintf("TCP port \"%s\" is not defined for %s",
     {
     addr->transport_return = PANIC;
     addr->message = string_sprintf("TCP port \"%s\" is not defined for %s",


@@ -144,9 +140,69 @@ return TRUE;
 
 
 
 
 
 

+#ifdef TCP_FASTOPEN
+static void
+tfo_out_check(int sock)
+{
+# if defined(TCP_INFO) && defined(EXIM_HAVE_TCPI_UNACKED)
+struct tcp_info tinfo;
+socklen_t len = sizeof(tinfo);
+
+if (getsockopt(sock, IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0)
+  {
+  switch (tcp_out_fastopen)
+    {
+      /* This is a somewhat dubious detection method; totally undocumented so likely
+      to fail in future kernels.  There seems to be no documented way.  What we really
+      want to know is if the server sent smtp-banner data before our ACK of his SYN,ACK
+      hit him.  What this (possibly?) detects is whether we sent a TFO cookie with our
+      SYN, as distinct from a TFO request.  This gets a false-positive when the server
+      key is rotated; we send the old one (which this test sees) but the server returns
+      the new one and does not send its SMTP banner before we ACK his SYN,ACK.
+       To force that rotation case:
+       '# echo -n "00000000-00000000-00000000-0000000" >/proc/sys/net/ipv4/tcp_fastopen_key'
+      The kernel seems to be counting unack'd packets. */
+
+    case 1:
+      if (tinfo.tcpi_unacked > 1)
+       {
+       DEBUG(D_transport|D_v)
+         debug_printf("TCP_FASTOPEN tcpi_unacked %d\n", tinfo.tcpi_unacked);
+       tcp_out_fastopen = 2;
+       }
+      break;
+
+#ifdef notdef          /* This seems to always fire, meaning that we cannot tell
+                       whether the server accepted data we sent.  For now assume
+                       that it did. */
+
+      /* If there was data-on-SYN but we had to retrasnmit it, declare no TFO */
+
+    case 2:
+      if (!(tinfo.tcpi_options & TCPI_OPT_SYN_DATA))
+       {
+       DEBUG(D_transport|D_v) debug_printf("TFO: had to retransmit\n");
+       tcp_out_fastopen = 0;
+       }
+      break;
+#endif
+    }
+
+  }
+# endif
+}
+#endif
+
+
+/* Arguments as for smtp_connect(), plus
+  early_data   if non-NULL, data to be sent - preferably in the TCP SYN segment
+
+Returns:      connected socket number, or -1 with errno set
+*/
+

 int
 smtp_sock_connect(host_item * host, int host_af, int port, uschar * interface,
 int
 smtp_sock_connect(host_item * host, int host_af, int port, uschar * interface,

-  transport_instance * tb, int timeout)
+  transport_instance * tb, int timeout, const blob * early_data)

 {
 smtp_transport_options_block * ob =
   (smtp_transport_options_block *)tb->options_block;
 {
 smtp_transport_options_block * ob =
   (smtp_transport_options_block *)tb->options_block;


@@ -155,10 +211,11 @@ int dscp_value;
 int dscp_level;
 int dscp_option;
 int sock;
 int dscp_level;
 int dscp_option;
 int sock;

-int on = 1;

 int save_errno = 0;
 int save_errno = 0;

+const blob * fastopen_blob = NULL;

 
 

-#ifdef EXPERIMENTAL_EVENT
+
+#ifndef DISABLE_EVENT

 deliver_host_address = host->address;
 deliver_host_port = port;
 if (event_raise(tb->event_action, US"tcp:connect", NULL)) return -1;
 deliver_host_address = host->address;
 deliver_host_port = port;
 if (event_raise(tb->event_action, US"tcp:connect", NULL)) return -1;


@@ -168,7 +225,9 @@ if ((sock = ip_socket(SOCK_STREAM, host_af)) < 0) return -1;
 
 /* Set TCP_NODELAY; Exim does its own buffering. */
 
 
 /* Set TCP_NODELAY; Exim does its own buffering. */
 

-setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (uschar *)(&on), sizeof(on));
+if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, US &on, sizeof(on)))
+  HDEBUG(D_transport|D_acl|D_v)
+    debug_printf_indent("failed to set NODELAY: %s ", strerror(errno));

 
 /* Set DSCP value, if we can. For now, if we fail to set the value, we don't
 bomb out, just log it and continue in default traffic class. */
 
 /* Set DSCP value, if we can. For now, if we fail to set the value, we don't
 bomb out, just log it and continue in default traffic class. */


@@ -176,10 +235,10 @@ bomb out, just log it and continue in default traffic class. */
 if (dscp && dscp_lookup(dscp, host_af, &dscp_level, &dscp_option, &dscp_value))
   {
   HDEBUG(D_transport|D_acl|D_v)
 if (dscp && dscp_lookup(dscp, host_af, &dscp_level, &dscp_option, &dscp_value))
   {
   HDEBUG(D_transport|D_acl|D_v)

-    debug_printf("DSCP \"%s\"=%x ", dscp, dscp_value);
+    debug_printf_indent("DSCP \"%s\"=%x ", dscp, dscp_value);

   if (setsockopt(sock, dscp_level, dscp_option, &dscp_value, sizeof(dscp_value)) < 0)
     HDEBUG(D_transport|D_acl|D_v)
   if (setsockopt(sock, dscp_level, dscp_option, &dscp_value, sizeof(dscp_value)) < 0)
     HDEBUG(D_transport|D_acl|D_v)

-      debug_printf("failed to set DSCP: %s ", strerror(errno));
+      debug_printf_indent("failed to set DSCP: %s ", strerror(errno));

   /* If the kernel supports IPv4 and IPv6 on an IPv6 socket, we need to set the
   option for both; ignore failures here */
   if (host_af == AF_INET6 &&
   /* If the kernel supports IPv4 and IPv6 on an IPv6 socket, we need to set the
   option for both; ignore failures here */
   if (host_af == AF_INET6 &&


@@ -194,15 +253,27 @@ if (interface && ip_bind(sock, host_af, interface, 0) < 0)
   {
   save_errno = errno;
   HDEBUG(D_transport|D_acl|D_v)
   {
   save_errno = errno;
   HDEBUG(D_transport|D_acl|D_v)

-    debug_printf("unable to bind outgoing SMTP call to %s: %s", interface,
+    debug_printf_indent("unable to bind outgoing SMTP call to %s: %s", interface,

     strerror(errno));
   }
 
 /* Connect to the remote host, and add keepalive to the socket before returning
     strerror(errno));
   }
 
 /* Connect to the remote host, and add keepalive to the socket before returning

-it, if requested. */
+it, if requested.  If the build supports TFO, request it - and if the caller
+requested some early-data then include that in the TFO request. */

 
 

-else if (ip_connect(sock, host_af, host->address, port, timeout) < 0)
-  save_errno = errno;
+else
+  {
+#ifdef TCP_FASTOPEN
+  if (verify_check_given_host(&ob->hosts_try_fastopen, host) == OK)
+    fastopen_blob = early_data ? early_data : &tcp_fastopen_nodata;
+#endif
+
+  if (ip_connect(sock, host_af, host->address, port, timeout, fastopen_blob) < 0)
+    save_errno = errno;
+  else if (early_data && !fastopen_blob && early_data->data && early_data->len)
+    if (send(sock, early_data->data, early_data->len, 0) < 0)
+      save_errno = errno;
+  }

 
 /* Either bind() or connect() failed */
 
 
 /* Either bind() or connect() failed */
 


@@ -210,7 +281,7 @@ if (save_errno != 0)
   {
   HDEBUG(D_transport|D_acl|D_v)
     {
   {
   HDEBUG(D_transport|D_acl|D_v)
     {

-    debug_printf("failed: %s", CUstrerror(save_errno));
+    debug_printf_indent("failed: %s", CUstrerror(save_errno));

     if (save_errno == ETIMEDOUT)
       debug_printf(" (timeout=%s)", readconf_printtime(timeout));
     debug_printf("\n");
     if (save_errno == ETIMEDOUT)
       debug_printf(" (timeout=%s)", readconf_printtime(timeout));
     debug_printf("\n");


@@ -226,7 +297,7 @@ else
   {
   union sockaddr_46 interface_sock;
   EXIM_SOCKLEN_T size = sizeof(interface_sock);
   {
   union sockaddr_46 interface_sock;
   EXIM_SOCKLEN_T size = sizeof(interface_sock);

-  HDEBUG(D_transport|D_acl|D_v) debug_printf("connected\n");
+  HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("connected\n");

   if (getsockname(sock, (struct sockaddr *)(&interface_sock), &size) == 0)
     sending_ip_address = host_ntoa(-1, &interface_sock, NULL, &sending_port);
   else
   if (getsockname(sock, (struct sockaddr *)(&interface_sock), &size) == 0)
     sending_ip_address = host_ntoa(-1, &interface_sock, NULL, &sending_port);
   else


@@ -237,10 +308,31 @@ else
     return -1;
     }
   if (ob->keepalive) ip_keepalive(sock, host->address, TRUE);
     return -1;
     }
   if (ob->keepalive) ip_keepalive(sock, host->address, TRUE);

+#ifdef TCP_FASTOPEN
+  if (fastopen_blob) tfo_out_check(sock);
+#endif

   return sock;
   }
 }
 
   return sock;
   }
 }
 

+
+
+
+
+void
+smtp_port_for_connect(host_item * host, int port)
+{
+if (host->port != PORT_NONE)
+  {
+  HDEBUG(D_transport|D_acl|D_v)
+    debug_printf_indent("Transport port=%d replaced by host-specific port=%d\n", port,
+      host->port);
+  port = host->port;
+  }
+else host->port = port;    /* Set the port actually used */
+}
+
+

 /*************************************************
 *           Connect to remote host               *
 *************************************************/
 /*************************************************
 *           Connect to remote host               *
 *************************************************/


@@ -250,15 +342,9 @@ detected by checking for a colon in the address. AF_INET6 is defined even on
 non-IPv6 systems, to enable the code to be less messy. However, on such systems
 host->address will always be an IPv4 address.
 
 non-IPv6 systems, to enable the code to be less messy. However, on such systems
 host->address will always be an IPv4 address.
 

-The port field in the host item is used if it is set (usually router from SRV
-records or elsewhere). In other cases, the default passed as an argument is
-used, and the host item is updated with its value.
-

 Arguments:
 Arguments:

-  host        host item containing name and address (and sometimes port)
+  host        host item containing name and address and port

   host_af     AF_INET or AF_INET6
   host_af     AF_INET or AF_INET6

-  port        default remote port to connect to, in host byte order, for those
-                hosts whose port setting is PORT_NONE

   interface   outgoing interface address or NULL
   timeout     timeout value or 0
   tb          transport
   interface   outgoing interface address or NULL
   timeout     timeout value or 0
   tb          transport


@@ -267,42 +353,35 @@ Returns:      connected socket number, or -1 with errno set
 */
 
 int
 */
 
 int

-smtp_connect(host_item *host, int host_af, int port, uschar *interface,
+smtp_connect(host_item *host, int host_af, uschar *interface,

   int timeout, transport_instance * tb)
 {
   int timeout, transport_instance * tb)
 {

-#ifdef EXPERIMENTAL_SOCKS
+int port = host->port;
+#ifdef SUPPORT_SOCKS

 smtp_transport_options_block * ob =
   (smtp_transport_options_block *)tb->options_block;
 #endif
 
 smtp_transport_options_block * ob =
   (smtp_transport_options_block *)tb->options_block;
 #endif
 

-if (host->port != PORT_NONE)
-  {
-  HDEBUG(D_transport|D_acl|D_v)
-    debug_printf("Transport port=%d replaced by host-specific port=%d\n", port,
-      host->port);
-  port = host->port;
-  }
-else host->port = port;    /* Set the port actually used */
+callout_address = string_sprintf("[%s]:%d", host->address, port);

 
 HDEBUG(D_transport|D_acl|D_v)
   {
   uschar * s = US" ";
   if (interface) s = string_sprintf(" from %s ", interface);
 
 HDEBUG(D_transport|D_acl|D_v)
   {
   uschar * s = US" ";
   if (interface) s = string_sprintf(" from %s ", interface);

-#ifdef EXPERIMENTAL_SOCKS
+#ifdef SUPPORT_SOCKS

   if (ob->socks_proxy) s = string_sprintf("%svia proxy ", s);
 #endif
   if (ob->socks_proxy) s = string_sprintf("%svia proxy ", s);
 #endif

-  debug_printf("Connecting to %s [%s]:%d%s... ",
-    host->name, host->address, port, s);
+  debug_printf_indent("Connecting to %s %s%s... ", host->name, callout_address, s);

   }
 
 /* Create and connect the socket */
 
   }
 
 /* Create and connect the socket */
 

-#ifdef EXPERIMENTAL_SOCKS
+#ifdef SUPPORT_SOCKS

 if (ob->socks_proxy)
   return socks_sock_connect(host, host_af, port, interface, tb, timeout);
 #endif
 
 if (ob->socks_proxy)
   return socks_sock_connect(host, host_af, port, interface, tb, timeout);
 #endif
 

-return smtp_sock_connect(host, host_af, port, interface, tb, timeout);
+return smtp_sock_connect(host, host_af, port, interface, tb, timeout, NULL);

 }
 
 
 }
 
 


@@ -316,25 +395,37 @@ pipelining.
 
 Argument:
   outblock   the SMTP output block
 
 Argument:
   outblock   the SMTP output block

+  mode      further data expected, or plain

 
 Returns:     TRUE if OK, FALSE on error, with errno set
 */
 
 static BOOL
 
 Returns:     TRUE if OK, FALSE on error, with errno set
 */
 
 static BOOL

-flush_buffer(smtp_outblock *outblock)
+flush_buffer(smtp_outblock * outblock, int mode)

 {
 int rc;
 {
 int rc;

+int n = outblock->ptr - outblock->buffer;
+BOOL more = mode == SCMD_MORE;
+
+HDEBUG(D_transport|D_acl) debug_printf_indent("cmd buf flush %d bytes%s\n", n,
+  more ? " (more expected)" : "");

 
 #ifdef SUPPORT_TLS
 
 #ifdef SUPPORT_TLS

-if (tls_out.active == outblock->sock)
-  rc = tls_write(FALSE, outblock->buffer, outblock->ptr - outblock->buffer);
+if (outblock->cctx->tls_ctx)
+  rc = tls_write(outblock->cctx->tls_ctx, outblock->buffer, n, more);

 else
 #endif
 else
 #endif

+  rc = send(outblock->cctx->sock, outblock->buffer, n,
+#ifdef MSG_MORE
+           more ? MSG_MORE : 0
+#else
+           0
+#endif
+          );

 
 

-rc = send(outblock->sock, outblock->buffer, outblock->ptr - outblock->buffer, 0);

 if (rc <= 0)
   {
 if (rc <= 0)
   {

-  HDEBUG(D_transport|D_acl) debug_printf("send failed: %s\n", strerror(errno));
+  HDEBUG(D_transport|D_acl) debug_printf_indent("send failed: %s\n", strerror(errno));

   return FALSE;
   }
 
   return FALSE;
   }
 


@@ -353,10 +444,11 @@ return TRUE;
 any error message.
 
 Arguments:
 any error message.
 
 Arguments:

-  outblock   contains buffer for pipelining, and socket
-  noflush    if TRUE, save the command in the output buffer, for pipelining
+  sx        SMTP connection, contains buffer for pipelining, and socket
+  mode       buffer, write-with-more-likely, write

   format     a format, starting with one of
              of HELO, MAIL FROM, RCPT TO, DATA, ".", or QUIT.
   format     a format, starting with one of
              of HELO, MAIL FROM, RCPT TO, DATA, ".", or QUIT.

+            If NULL, flush pipeline buffer only.

   ...        data for the format
 
 Returns:     0 if command added to pipelining buffer, with nothing transmitted
   ...        data for the format
 
 Returns:     0 if command added to pipelining buffer, with nothing transmitted


@@ -365,59 +457,63 @@ Returns:     0 if command added to pipelining buffer, with nothing transmitted
 */
 
 int
 */
 
 int

-smtp_write_command(smtp_outblock *outblock, BOOL noflush, const char *format, ...)
+smtp_write_command(void * sx, int mode, const char *format, ...)

 {
 {

+smtp_outblock * outblock = &((smtp_context *)sx)->outblock;

 int count;
 int rc = 0;
 va_list ap;
 
 int count;
 int rc = 0;
 va_list ap;
 

-va_start(ap, format);
-if (!string_vformat(big_buffer, big_buffer_size, CS format, ap))
-  log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong write_command in outgoing "
-    "SMTP");
-va_end(ap);
-count = Ustrlen(big_buffer);
-
-if (count > outblock->buffersize)
-  log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong write_command in outgoing "
-    "SMTP");
-
-if (count > outblock->buffersize - (outblock->ptr - outblock->buffer))
+if (format)

   {
   {

-  rc = outblock->cmd_count;                 /* flush resets */
-  if (!flush_buffer(outblock)) return -1;
-  }
+  va_start(ap, format);
+  if (!string_vformat(big_buffer, big_buffer_size, CS format, ap))
+    log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong write_command in outgoing "
+      "SMTP");
+  va_end(ap);
+  count = Ustrlen(big_buffer);
+
+  if (count > outblock->buffersize)
+    log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong write_command in outgoing "
+      "SMTP");
+
+  if (count > outblock->buffersize - (outblock->ptr - outblock->buffer))
+    {
+    rc = outblock->cmd_count;                 /* flush resets */
+    if (!flush_buffer(outblock, SCMD_FLUSH)) return -1;
+    }

 
 

-Ustrncpy(CS outblock->ptr, big_buffer, count);
-outblock->ptr += count;
-outblock->cmd_count++;
-count -= 2;
-big_buffer[count] = 0;     /* remove \r\n for error message */
+  Ustrncpy(CS outblock->ptr, big_buffer, count);
+  outblock->ptr += count;
+  outblock->cmd_count++;
+  count -= 2;
+  big_buffer[count] = 0;     /* remove \r\n for error message */

 
 

-/* We want to hide the actual data sent in AUTH transactions from reflections
-and logs. While authenticating, a flag is set in the outblock to enable this.
-The AUTH command itself gets any data flattened. Other lines are flattened
-completely. */
+  /* We want to hide the actual data sent in AUTH transactions from reflections
+  and logs. While authenticating, a flag is set in the outblock to enable this.
+  The AUTH command itself gets any data flattened. Other lines are flattened
+  completely. */

 
 

-if (outblock->authenticating)
-  {
-  uschar *p = big_buffer;
-  if (Ustrncmp(big_buffer, "AUTH ", 5) == 0)
+  if (outblock->authenticating)

     {
     {

-    p += 5;
-    while (isspace(*p)) p++;
-    while (!isspace(*p)) p++;
-    while (isspace(*p)) p++;
+    uschar *p = big_buffer;
+    if (Ustrncmp(big_buffer, "AUTH ", 5) == 0)
+      {
+      p += 5;
+      while (isspace(*p)) p++;
+      while (!isspace(*p)) p++;
+      while (isspace(*p)) p++;
+      }
+    while (*p != 0) *p++ = '*';

     }
     }

-  while (*p != 0) *p++ = '*';
-  }

 
 

-HDEBUG(D_transport|D_acl|D_v) debug_printf("  SMTP>> %s\n", big_buffer);
+  HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP>> %s\n", big_buffer);
+  }

 
 

-if (!noflush)
+if (mode != SCMD_BUFFER)

   {
   rc += outblock->cmd_count;                /* flush resets */
   {
   rc += outblock->cmd_count;                /* flush resets */

-  if (!flush_buffer(outblock)) return -1;
+  if (!flush_buffer(outblock, mode)) return -1;

   }
 
 return rc;
   }
 
 return rc;


@@ -451,7 +547,7 @@ read_response_line(smtp_inblock *inblock, uschar *buffer, int size, int timeout)
 uschar *p = buffer;
 uschar *ptr = inblock->ptr;
 uschar *ptrend = inblock->ptrend;
 uschar *p = buffer;
 uschar *ptr = inblock->ptr;
 uschar *ptrend = inblock->ptrend;

-int sock = inblock->sock;
+client_conn_ctx * cctx = inblock->cctx;

 
 /* Loop for reading multiple packets or reading another packet after emptying
 a previously-read one. */
 
 /* Loop for reading multiple packets or reading another packet after emptying
 a previously-read one. */


@@ -489,15 +585,20 @@ for (;;)
 
   /* Need to read a new input packet. */
 
 
   /* Need to read a new input packet. */
 

-  rc = ip_recv(sock, inblock->buffer, inblock->buffersize, timeout);
-  if (rc <= 0) break;
+  if((rc = ip_recv(cctx, inblock->buffer, inblock->buffersize, timeout)) <= 0)
+    {
+    DEBUG(D_deliver|D_transport|D_acl)
+      debug_printf_indent(errno ? "  SMTP(%s)<<\n" : "  SMTP(closed)<<\n",
+       strerror(errno));
+    break;
+    }

 
   /* Another block of data has been successfully read. Set up the pointers
   and let the loop continue. */
 
   ptrend = inblock->ptrend = inblock->buffer + rc;
   ptr = inblock->buffer;
 
   /* Another block of data has been successfully read. Set up the pointers
   and let the loop continue. */
 
   ptrend = inblock->ptrend = inblock->buffer + rc;
   ptr = inblock->buffer;

-  DEBUG(D_transport|D_acl) debug_printf("read response data: size=%d\n", rc);
+  DEBUG(D_transport|D_acl) debug_printf_indent("read response data: size=%d\n", rc);

   }
 
 /* Get here if there has been some kind of recv() error; errno is set, but we
   }
 
 /* Get here if there has been some kind of recv() error; errno is set, but we


@@ -523,25 +624,27 @@ also returned after a reading error. In this case buffer[0] will be zero, and
 the error code will be in errno.
 
 Arguments:
 the error code will be in errno.
 
 Arguments:

-  inblock   the SMTP input block (contains holding buffer, socket, etc.)
+  sx        the SMTP connection (contains input block with holding buffer,
+               socket, etc.)

   buffer    where to put the response
   size      the size of the buffer
   okdigit   the expected first digit of the response
   buffer    where to put the response
   size      the size of the buffer
   okdigit   the expected first digit of the response

-  timeout   the timeout to use
+  timeout   the timeout to use, in seconds

 
 Returns:    TRUE if a valid, non-error response was received; else FALSE
 */
 
 BOOL
 
 Returns:    TRUE if a valid, non-error response was received; else FALSE
 */
 
 BOOL

-smtp_read_response(smtp_inblock *inblock, uschar *buffer, int size, int okdigit,
+smtp_read_response(void * sx, uschar *buffer, int size, int okdigit,

    int timeout)
 {
    int timeout)
 {

+smtp_inblock * inblock = &((smtp_context *)sx)->inblock;

 uschar *ptr = buffer;
 int count;
 
 errno = 0;  /* Ensure errno starts out zero */
 
 uschar *ptr = buffer;
 int count;
 
 errno = 0;  /* Ensure errno starts out zero */
 

-/* This is a loop to read and concatentate the lines that make up a multi-line
+/* This is a loop to read and concatenate the lines that make up a multi-line

 response. */
 
 for (;;)
 response. */
 
 for (;;)


@@ -550,7 +653,7 @@ for (;;)
     return FALSE;
 
   HDEBUG(D_transport|D_acl|D_v)
     return FALSE;
 
   HDEBUG(D_transport|D_acl|D_v)

-    debug_printf("  %s %s\n", (ptr == buffer)? "SMTP<<" : "      ", ptr);
+    debug_printf_indent("  %s %s\n", (ptr == buffer)? "SMTP<<" : "      ", ptr);

 
   /* Check the format of the response: it must start with three digits; if
   these are followed by a space or end of line, the response is complete. If
 
   /* Check the format of the response: it must start with three digits; if
   these are followed by a space or end of line, the response is complete. If