From 53c7b3a70978c2748f46d1d99211530750b1de22 Mon Sep 17 00:00:00 2001
From: Jeremy Harris <jgh146exb@wizmail.org>
Date: Sun, 8 Dec 2019 19:26:15 +0000
Subject: [PATCH] Fix macOS build

---
 src/src/smtp_in.c  | 38 +++++++++++++++++++++++---------------
 src/src/smtp_out.c |  4 +++-
 2 files changed, 26 insertions(+), 16 deletions(-)

diff --git a/src/src/smtp_in.c b/src/src/smtp_in.c
index 9a31247be..580fe9f91 100644
--- a/src/src/smtp_in.c
+++ b/src/src/smtp_in.c
@@ -2400,7 +2400,26 @@ return FALSE;
 static void
 tfo_in_check(void)
 {
-# ifdef TCP_INFO
+# ifdef __FreeBSD__
+int is_fastopen;
+socklen_t len = sizeof(is_fastopen);
+
+/* The tinfo TCPOPT_FAST_OPEN bit seems unreliable, and we don't see state
+TCP_SYN_RCV (as of 12.1) so no idea about data-use. */
+
+if (getsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_FASTOPEN, &is_fastopen, &len) == 0)
+  {
+  if (is_fastopen) 
+    {
+    DEBUG(D_receive)
+      debug_printf("TFO mode connection (TCP_FASTOPEN getsockopt)\n");
+    f.tcp_in_fastopen = TRUE;
+    }
+  }
+else DEBUG(D_receive)
+  debug_printf("TCP_INFO getsockopt: %s\n", strerror(errno));
+
+# elif defined(TCP_INFO)
 struct tcp_info tinfo;
 socklen_t len = sizeof(tinfo);
 
@@ -2409,7 +2428,7 @@ if (getsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0)
   if (tinfo.tcpi_options & TCPI_OPT_SYN_DATA)
     {
     DEBUG(D_receive)
-      debug_printf("TCP_FASTOPEN mode connection (ACKd data-on-SYN)\n");
+      debug_printf("TFO mode connection (ACKd data-on-SYN)\n");
     f.tcp_in_fastopen_data = f.tcp_in_fastopen = TRUE;
     }
   else
@@ -2417,20 +2436,9 @@ if (getsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0)
     if (tinfo.tcpi_state == TCP_SYN_RECV)	/* Not seen on FreeBSD 12.1 */
     {
     DEBUG(D_receive)
-      debug_printf("TCP_FASTOPEN mode connection (state TCP_SYN_RECV)\n");
+      debug_printf("TFO mode connection (state TCP_SYN_RECV)\n");
     f.tcp_in_fastopen = TRUE;
     }
-#  ifdef __FreeBSD__
-  else if (tinfo.tcpi_options & TCPOPT_FAST_OPEN)
-    {
-    /* This only tells us that some combination of the TCP options was used. It
-    can be a TFO-R received (as of 12.1).  However, pretend it shows real usage
-    (that an acceptable TFO-C was received and acted on).  Ignore the possibility
-    of data-on-SYN for now. */
-    DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (TFO option used)\n");
-    f.tcp_in_fastopen = TRUE;
-    }
-#  endif
 else DEBUG(D_receive)
   debug_printf("TCP_INFO getsockopt: %s\n", strerror(errno));
 # endif
@@ -3050,7 +3058,7 @@ smtp_printf("%s",
 handshake arrived.  If so we must have managed a TFO. */
 
 #ifdef TCP_FASTOPEN
-tfo_in_check();
+if (sender_host_address && !f.sender_host_notsocket) tfo_in_check();
 #endif
 
 return TRUE;
diff --git a/src/src/smtp_out.c b/src/src/smtp_out.c
index 3dc3a13fb..96ee15282 100644
--- a/src/src/smtp_out.c
+++ b/src/src/smtp_out.c
@@ -155,11 +155,11 @@ return TRUE;
 static void
 tfo_out_check(int sock)
 {
+# ifdef __FreeBSD__
 struct tcp_info tinfo;
 int val;
 socklen_t len = sizeof(val);
 
-# ifdef __FreeBSD__
 /* The observability as of 12.1 is not useful as a client, only telling us that
 a TFO option was used on SYN.  It could have been a TFO-R, or ignored by the
 server. */
@@ -177,6 +177,8 @@ switch (tcp_out_fastopen)
 
 # else	/* Linux & Apple */
 #  if defined(TCP_INFO) && defined(EXIM_HAVE_TCPI_UNACKED)
+struct tcp_info tinfo;
+socklen_t len = sizeof(tinfo);
 
 switch (tcp_out_fastopen)
   {
-- 
2.25.1