TFO: cleanup the TCP pure ack of SMTP banner

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

diff --git a/src/src/smtp_out.c b/src/src/smtp_out.c
index b1a25f70a702b1fbc9ee252c557763696cd82ec6..2a392e50fb53f14a3788f831428e1666049eda5a 100644 (file)
--- a/src/src/smtp_out.c
+++ b/src/src/smtp_out.c
@@ -349,14 +349,22 @@ else
     save_errno = errno;
   else if (early_data && !fastopen_blob && early_data->data && early_data->len)
     {
+    /* We had some early-data to send, but couldn't do TFO */
     HDEBUG(D_transport|D_acl|D_v)
       debug_printf("sending %ld nonTFO early-data\n", (long)early_data->len);
 
+#ifdef TCP_QUICKACK_notdef
+    (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
+#endif
     if (send(sock, early_data->data, early_data->len, 0) < 0)
       save_errno = errno;
     }
-#ifdef TCP_QUICKACK
-    (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
+#ifdef TCP_QUICKACK_notdef
+  /* Under TFO (with openssl & pipe-conn; testcase 4069, as of
+  5.10.8-100.fc32.x86_64) this seems to be inop.
+  Perhaps overwritten when we (client) go -> ESTABLISHED on seeing the 3rd-ACK?
+  For that case, added at smtp_reap_banner(). */
+  (void) setsockopt(sock, IPPROTO_TCP, TCP_QUICKACK, US &off, sizeof(off));
 #endif
   }