From 3a2d0a06f40144d8457622b221a40c22d7e341c8 Mon Sep 17 00:00:00 2001
From: Gregory Nutt <gnutt@nuttx.org>
Date: Thu, 22 Feb 2018 16:41:14 -0600
Subject: [PATCH] net/tcp:  Generalize Juho Grundstrom's IPv4 change for IPv6
 as well.

---
 net/tcp/tcp_send_buffered.c   | 38 +++++++++++++++++++++++++++++++----
 net/tcp/tcp_send_unbuffered.c | 38 +++++++++++++++++++++++++++++++----
 2 files changed, 68 insertions(+), 8 deletions(-)

diff --git a/net/tcp/tcp_send_buffered.c b/net/tcp/tcp_send_buffered.c
index 829cda78b6b..1d15f33e2ac 100644
--- a/net/tcp/tcp_send_buffered.c
+++ b/net/tcp/tcp_send_buffered.c
@@ -342,11 +342,41 @@ static inline bool psock_send_addrchck(FAR struct tcp_conn_s *conn)
   else
 #endif
     {
-#if !defined(CONFIG_NET_ICMPv6_NEIGHBOR)
-      return (neighbor_findentry(conn->u.ipv6.raddr) != NULL);
-#else
-      return true;
+      /* For historical reasons, we will return true if both the ARP and the
+       * routing table are disabled.
+       */
+
+      bool ret = true;
+#ifdef CONFIG_NET_ROUTE
+      net_ipv6addr_t router;
 #endif
+
+#if !defined(CONFIG_NET_ICMPv6_NEIGHBOR)
+      if (neighbor_findentry(conn->u.ipv6.raddr) != NULL)
+        {
+          /* Return true if the address was found in the ARP table */
+
+          return true;
+        }
+
+      /* Otherwise, return false */
+
+      ret = false;
+#endif
+#ifdef CONFIG_NET_ROUTE
+      if (net_ipv6_router(conn->u.ipv6.raddr, router) == OK)
+        {
+          /* Return true if the address was found in the routing table */
+
+          return true;
+        }
+
+      /* Otherwise, return false */
+
+      ret = false;
+#endif
+
+      return ret;
     }
 #endif /* CONFIG_NET_IPv6 */
 }
diff --git a/net/tcp/tcp_send_unbuffered.c b/net/tcp/tcp_send_unbuffered.c
index a24c964797b..58ec05fd0f5 100644
--- a/net/tcp/tcp_send_unbuffered.c
+++ b/net/tcp/tcp_send_unbuffered.c
@@ -292,11 +292,41 @@ static inline bool psock_send_addrchck(FAR struct tcp_conn_s *conn)
   else
 #endif
     {
-#if !defined(CONFIG_NET_ICMPv6_NEIGHBOR)
-      return (neighbor_findentry(conn->u.ipv6.raddr) != NULL);
-#else
-      return true;
+      /* For historical reasons, we will return true if both the ARP and the
+       * routing table are disabled.
+       */
+
+      bool ret = true;
+#ifdef CONFIG_NET_ROUTE
+      net_ipv6addr_t router;
 #endif
+
+#if !defined(CONFIG_NET_ICMPv6_NEIGHBOR)
+      if (neighbor_findentry(conn->u.ipv6.raddr) != NULL)
+        {
+          /* Return true if the address was found in the ARP table */
+
+          return true;
+        }
+
+      /* Otherwise, return false */
+
+      ret = false;
+#endif
+#ifdef CONFIG_NET_ROUTE
+      if (net_ipv6_router(conn->u.ipv6.raddr, router) == OK)
+        {
+          /* Return true if the address was found in the routing table */
+
+          return true;
+        }
+
+      /* Otherwise, return false */
+
+      ret = false;
+#endif
+
+      return ret;
     }
 #endif /* CONFIG_NET_IPv6 */
 }