TFO: better detection of client fast-open connections

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

diff --git a/src/src/smtp_out.c b/src/src/smtp_out.c
index 9221aa8680dd5985987574abf0d84424dbf7671d..db33ac66e26990c7ba0be6222ff0dd58106ee604 100644 (file)
--- a/src/src/smtp_out.c
+++ b/src/src/smtp_out.c
@@ -140,30 +140,6 @@ 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)
-  {
-  /* This is a somewhat dubious detection method; totally undocumented so likely
-  to fail in future kernels.  There seems to be no documented way. */
-
-  if (tinfo.tcpi_unacked > 1)
-    {
-    DEBUG(D_transport|D_v) debug_printf("TCP_FASTOPEN mode connection\n");
-    tcp_out_fastopen = TRUE;
-    }
-  }
-# endif
-}
-#endif
-
-
 /* Arguments as for smtp_connect(), plus
   early_data   if non-NULL, data to be sent - preferably in the TCP SYN segment
 
@@ -278,9 +254,6 @@ else
     return -1;
     }
   if (ob->keepalive) ip_keepalive(sock, host->address, TRUE);
-#ifdef TCP_FASTOPEN
-  tfo_out_check(sock);
-#endif
   return sock;
   }
 }