Networking: UDP and TCP MSS depends on the IP header size (as well as the link layer header size) and cannot be represented with a single value.

10 files changed, 153 insertions, 53 deletions

diff --git a/nuttx/fs/nfs/nfs_vfsops.c b/nuttx/fs/nfs/nfs_vfsops.c
index 7a26b530e..bb42093de 100644
--- a/nuttx/fs/nfs/nfs_vfsops.c
+++ b/nuttx/fs/nfs/nfs_vfsops.c
@@ -1722,9 +1722,9 @@ static int nfs_bind(FAR struct inode *blkdriver, FAR const void *data,
    * the minimum MSS for that case.
    */
 
-  if (buflen > MIN_UDP_MSS)
+  if (buflen > MIN_IPv4_UDP_MSS)
     {
-      buflen = MIN_UDP_MSS;
+      buflen = MIN_IPv4_UDP_MSS;
     }
 
   /* Create an instance of the mountpt state structure */
diff --git a/nuttx/include/nuttx/net/ip.h b/nuttx/include/nuttx/net/ip.h
index 3f01a22a5..e6a9f9c9d 100644
--- a/nuttx/include/nuttx/net/ip.h
+++ b/nuttx/include/nuttx/net/ip.h
@@ -300,7 +300,7 @@ struct net_ipv6hdr_s
    net_ipv4addr_cmp(net_ip4addr_conv32(addr1), net_ip4addr_conv32(addr2))
 #endif
 
-#ifdef CONFIG_NET_IPv4
+#ifdef CONFIG_NET_IPv6
 #  define net_ipv6addr_cmp(addr1, addr2) \
    (memcmp(&addr1, &addr2, sizeof(net_ipv6addr_t)) == 0)
 #  define net_ipv6addr_hdrcmp(addr1, addr2) \
diff --git a/nuttx/include/nuttx/net/netconfig.h b/nuttx/include/nuttx/net/netconfig.h
index 9df3a6f2c..560bf5d92 100644
--- a/nuttx/include/nuttx/net/netconfig.h
+++ b/nuttx/include/nuttx/net/netconfig.h
@@ -214,18 +214,52 @@
  * than NET_DEV_MTU(d) - NET_LL_HDRLEN(dev) - IPv4UDP_HDRLEN.
  */
 
-#define UDP_MSS(d)    (NET_DEV_MTU(d) - NET_LL_HDRLEN(d) - IPv4UDP_HDRLEN)
+#define UDP_MSS(d,h)         (NET_DEV_MTU(d) - NET_LL_HDRLEN(d) - (h))
+
+/* If Ethernet is supported, then it will have the smaller MSS */
+
+#ifdef CONFIG_NET_SLIP
+#  define SLIP_UDP_MSS(h)    (CONFIG_NET_SLIP_MTU - (h))
+#  define __MIN_UDP_MSS(h)   SLIP_UDP_MSS(h)
+#endif
 
 #ifdef CONFIG_NET_ETHERNET
-#  define MIN_UDP_MSS (CONFIG_NET_ETH_MTU - ETH_HDRLEN - IPv4UDP_HDRLEN)
-#else /* if defined(CONFIG_NET_SLIP) */
-#  define MIN_UDP_MSS (CONFIG_NET_SLIP_MTU - IPv4UDP_HDRLEN)
+#  define ETH_UDP_MSS(h)     (CONFIG_NET_ETH_MTU - ETH_HDRLEN - (h))
+#  undef __MIN_UDP_MSS
+#  define __MIN_UDP_MSS(h)   ETH_UDP_MSS(h)
+#  define __MAX_UDP_MSS(h)   ETH_UDP_MSS(h)
 #endif
 
+/* If SLIP is supported, then it will have the larger MSS */
+
 #ifdef CONFIG_NET_SLIP
-#  define MAX_UDP_MSS (CONFIG_NET_SLIP_MTU - IPv4UDP_HDRLEN)
-#else /* if defined(CONFIG_NET_ETHERNET) */
-#  define MAX_UDP_MSS (CONFIG_NET_ETH_MTU - ETH_HDRLEN - IPv4UDP_HDRLEN)
+#  undef __MAX_UDP_MSS
+#  define __MAX_UDP_MSS(h)   SLIP_UDP_MSS(h)
+#endif
+
+/* If IPv4 is supported, it will have the larger MSS */
+
+#ifdef CONFIG_NET_IPv6
+#  define UDP_IPv6_MSS(d)    UDP_MSS(d,IPv6_HDRLEN)
+#  define ETH_IPv6_UDP_MSS   ETH_UDP_MSS(IPv6_HDRLEN)
+#  define SLIP_IPv6_UDP_MSS  SLIP_UDP_MSS(IPv6_HDRLEN)
+#  define MAX_UDP_MSS        __MAX_UDP_MSS(IPv6_HDRLEN)
+#endif
+
+#ifdef CONFIG_NET_IPv4
+#  define UDP_IPv4_MSS(d)    UDP_MSS(d,IPv4_HDRLEN)
+#  define ETH_IPv4_UDP_MSS   ETH_UDP_MSS(IPv4_HDRLEN)
+#  define SLIP_IPv4_UDP_MSS  SLIP_UDP_MSS(IPv4_HDRLEN)
+#  define MIN_UDP_MSS        __MIN_UDP_MSS(IPv4_HDRLEN)
+#  undef MAX_UDP_MSS
+#  define MAX_UDP_MSS        __MAX_UDP_MSS(IPv4_HDRLEN)
+#endif
+
+/* If IPv6 is support, it will have the smaller MSS */
+
+#ifdef CONFIG_NET_IPv6
+#  undef MIN_UDP_MSS
+#  define MIN_UDP_MSS        __MIN_UDP_MSS(IPv6_HDRLEN)
 #endif
 
 /* TCP configuration options */
@@ -296,20 +330,52 @@
  * the minimum MSS for that case.
  */
 
-#define TCP_MSS(d)    (NET_DEV_MTU(d) - NET_LL_HDRLEN(d) - IPv4TCP_HDRLEN)
+#define TCP_MSS(d,h)        (NET_DEV_MTU(d) - NET_LL_HDRLEN(d) - (h))
+
+/* If Ethernet is supported, then it will have the smaller MSS */
+
+#ifdef CONFIG_NET_SLIP
+#  define SLIP_TCP_MSS(h)   (CONFIG_NET_SLIP_MTU - (h))
+#  define __MIN_TCP_MSS(h)  SLIP_TCP_MSS(h)
+#endif
 
 #ifdef CONFIG_NET_ETHERNET
-#  define ETH_TCP_MSS  (CONFIG_NET_ETH_MTU - ETH_HDRLEN - IPv4TCP_HDRLEN)
-#  define MIN_TCP_MSS  ETH_TCP_MSS
-#elif defined(CONFIG_NET_SLIP)
-#  define SLIP_TCP_MSS (CONFIG_NET_SLIP_MTU - IPv4TCP_HDRLEN)
-#  define MIN_TCP_MSS  SLIP_TCP_MSS
+#  define ETH_TCP_MSS(h)    (CONFIG_NET_ETH_MTU - ETH_HDRLEN - (h))
+#  undef __MIN_TCP_MSS
+#  define __MIN_TCP_MSS(h)  ETH_TCP_MSS(h)
+#  define __MAX_TCP_MSS(h)  ETH_TCP_MSS(h)
 #endif
 
+/* If SLIP is supported, then it will have the larger MSS */
+
 #ifdef CONFIG_NET_SLIP
-#  define MAX_TCP_MSS  SLIP_TCP_MSS
-#elif defined(CONFIG_NET_ETHERNET)
-#  define MAX_TCP_MSS  ETH_TCP_MSS
+#  undef __MAX_TCP_MSS
+#  define __MAX_TCP_MSS(h)  SLIP_TCP_MSS(h)
+#endif
+
+/* If IPv4 is support, it will have the larger MSS */
+
+#ifdef CONFIG_NET_IPv6
+#  define TCP_IPv6_MSS(d)   TCP_MSS(d,IPv6_HDRLEN)
+#  define ETH_IPv6_TCP_MSS  ETH_TCP_MSS(IPv6_HDRLEN)
+#  define SLIP_IPv6_TCP_MSS SLIP_TCP_MSS(IPv6_HDRLEN)
+#  define MAX_TCP_MSS       __MAX_TCP_MSS(IPv6_HDRLEN)
+#endif
+
+#ifdef CONFIG_NET_IPv4
+#  define TCP_IPv4_MSS(d)   TCP_MSS(d,IPv4_HDRLEN)
+#  define ETH_IPv4_TCP_MSS  ETH_TCP_MSS(IPv4_HDRLEN)
+#  define SLIP_IPv4_TCP_MSS SLIP_TCP_MSS(IPv4_HDRLEN)
+#  define MIN_TCP_MSS       __MIN_TCP_MSS(IPv4_HDRLEN)
+#  undef MAX_TCP_MSS
+#  define MAX_TCP_MSS       __MAX_TCP_MSS(IPv4_HDRLEN)
+#endif
+
+/* If IPv6 is supported, it will have the smaller MSS */
+
+#ifdef CONFIG_NET_IPv6
+#  undef MIN_TCP_MSS
+#  define MIN_TCP_MSS       __MIN_TCP_MSS(IPv6_HDRLEN)
 #endif
 
 /* The size of the advertised receiver's window.
diff --git a/nuttx/include/nuttx/net/tcp.h b/nuttx/include/nuttx/net/tcp.h
index 8a33f81cd..c6b9ddf17 100644
--- a/nuttx/include/nuttx/net/tcp.h
+++ b/nuttx/include/nuttx/net/tcp.h
@@ -119,10 +119,22 @@
  * This is a long established rule.
  */
 
-#define TCP_INITIAL_MSS(d)  (TCP_MSS(d) > 576 ? 576 : TCP_MSS(d))
+#define TCP_INITIAL_MSS(d,h)       (TCP_MSS(d,h) > 576 ? 576 : TCP_MSS(d,h))
 
-#define MIN_TCP_INITIAL_MSS (MIN_TCP_MSS > 576 ? 576 : MIN_TCP_MSS)
-#define MAX_TCP_INITIAL_MSS (MAX_TCP_MSS > 576 ? 576 : MAX_TCP_MSS)
+#define MIN_TCP_INITIAL_MSS(h)     (__MIN_TCP_MSS(h) > 576 ? 576 : __MIN_TCP_MSS(h))
+#define MAX_TCP_INITIAL_MSS(h)     (__MAX_TCP_MSS(h) > 576 ? 576 : __MAX_TCP_MSS(h))
+
+#ifdef CONFIG_NET_IPv4
+#  define TCP_IPv4_INITIAL_MSS(d)  TCP_INITIAL_MSS(d,IPv4_HDRLEN)
+#  define MIN_IPv4_TCP_INITIAL_MSS MIN_TCP_INITIAL_MSS(IPv4_HDRLEN)
+#  define MAX_IPv4_TCP_INITIAL_MSS MAX_TCP_INITIAL_MSS(IPv4_HDRLEN)
+#endif
+
+#ifdef CONFIG_NET_IPv6
+#  define TCP_IPv6_INITIAL_MSS(d)  TCP_INITIAL_MSS(d,IPv6_HDRLEN)
+#  define MIN_IPv6_TCP_INITIAL_MSS MIN_TCP_INITIAL_MSS(IPv6_HDRLEN)
+#  define MAX_IPv6_TCP_INITIAL_MSS MAX_TCP_INITIAL_MSS(IPv6_HDRLEN)
+#endif
 
 /****************************************************************************
  * Public Type Definitions
diff --git a/nuttx/net/icmpv6/icmpv6_input.c b/nuttx/net/icmpv6/icmpv6_input.c
index 6b53a13f1..da17c3c60 100644
--- a/nuttx/net/icmpv6/icmpv6_input.c
+++ b/nuttx/net/icmpv6/icmpv6_input.c
@@ -122,7 +122,7 @@ void icmpv6_input(FAR struct net_driver_s *dev)
 
   if (picmp->type == ICMPv6_NEIGHBOR_SOLICITATION)
     {
-      if (net_ipv6addr_cmp(picmp->icmpv6data, dev->d_ipaddr))
+      if (net_ipv6addr_cmp(picmp->icmpv6data, dev->d_ipv6addr))
         {
           if (picmp->options[0] == ICMPv6_OPTION_SOURCE_LINK_ADDRESS)
             {
@@ -142,7 +142,7 @@ void icmpv6_input(FAR struct net_driver_s *dev)
           picmp->reserved1 = picmp->reserved2 = picmp->reserved3 = 0;
 
           net_ipv6addr_copy(picmp->destipaddr, picmp->srcipaddr);
-          net_ipv6addr_copy(picmp->srcipaddr, dev->d_ipaddr);
+          net_ipv6addr_copy(picmp->srcipaddr, dev->d_ipv6addr);
 
           picmp->options[0]   = ICMPv6_OPTION_TARGET_LINK_ADDRESS;
           picmp->options[1]   = 1;  /* Options length, 1 = 8 bytes. */
@@ -166,7 +166,7 @@ void icmpv6_input(FAR struct net_driver_s *dev)
       picmp->type = ICMPv6_ECHO_REPLY;
 
       net_ipv6addr_copy(picmp->destipaddr, picmp->srcipaddr);
-      net_ipv6addr_copy(picmp->srcipaddr, dev->d_ipaddr);
+      net_ipv6addr_copy(picmp->srcipaddr, dev->d_ipv6addr);
 
       picmp->icmpv6chksum = 0;
       picmp->icmpv6chksum = ~icmpv6_chksum(dev);
diff --git a/nuttx/net/socket/connect.c b/nuttx/net/socket/connect.c
index 51e4b8426..838cec0ba 100644
--- a/nuttx/net/socket/connect.c
+++ b/nuttx/net/socket/connect.c
@@ -259,7 +259,7 @@ static uint16_t psock_connect_interrupt(FAR struct net_driver_s *dev,
        */
 
       DEBUGASSERT(pstate->tc_conn);
-      pstate->tc_conn->mss = TCP_INITIAL_MSS(dev);
+      pstate->tc_conn->mss = TCP_IPv4_INITIAL_MSS(dev);
 #endif
 
       /* Wake up the waiting thread */
diff --git a/nuttx/net/tcp/tcp_conn.c b/nuttx/net/tcp/tcp_conn.c
index f2cc71914..6756fa6fb 100644
--- a/nuttx/net/tcp/tcp_conn.c
+++ b/nuttx/net/tcp/tcp_conn.c
@@ -599,7 +599,7 @@ FAR struct tcp_conn_s *tcp_alloc_accept(FAR struct net_driver_s *dev,
       conn->nrtx          = 0;
       conn->lport         = tcp->destport;
       conn->rport         = tcp->srcport;
-      conn->mss           = TCP_INITIAL_MSS(dev);
+      conn->mss           = TCP_IPv4_INITIAL_MSS(dev);
       net_ipv4addr_copy(conn->u.ipv4.raddr, net_ip4addr_conv32(ip->srcipaddr));
 #ifdef CONFIG_NETDEV_MULTINIC
       net_ipv4addr_copy(conn->u.ipv4.laddr, net_ip4addr_conv32(ip->destipaddr));
@@ -780,7 +780,7 @@ int tcp_connect(FAR struct tcp_conn_s *conn,
   conn->tcpstateflags = TCP_SYN_SENT;
   tcp_initsequence(conn->sndseq);
 
-  conn->mss        = MIN_TCP_INITIAL_MSS;
+  conn->mss        = MIN_IPv4_TCP_INITIAL_MSS;
   conn->unacked    = 1;    /* TCP length of the SYN is one. */
   conn->nrtx       = 0;
   conn->timer      = 1;    /* Send the SYN next time around. */
diff --git a/nuttx/net/tcp/tcp_input.c b/nuttx/net/tcp/tcp_input.c
index c7c808afd..f851c67ea 100644
--- a/nuttx/net/tcp/tcp_input.c
+++ b/nuttx/net/tcp/tcp_input.c
@@ -95,10 +95,11 @@
  *
  ****************************************************************************/
 
-static void tcp_input(FAR struct net_driver_s *dev,
-                      FAR struct tcp_hdr_s *tcp, unsigned int tcpiplen)
+static void tcp_input(FAR struct net_driver_s *dev, unsigned int iplen)
 {
+  FAR struct tcp_hdr_s *tcp;
   FAR struct tcp_conn_s *conn = NULL;
+  unsigned int tcpiplen;
   unsigned int hdrlen;
   uint16_t tmp16;
   uint16_t flags;
@@ -113,6 +114,16 @@ static void tcp_input(FAR struct net_driver_s *dev,
   g_netstats.tcp.recv++;
 #endif
 
+  /* Get a pointer to the TCP header.  The TCP header lies just after the
+   * the link layer header and the IP header.
+   */
+
+  tcp = (FAR struct tcp_hdr_s *)&dev->d_buf[iplen + NET_LL_HDRLEN(dev)];
+
+  /* Get the size of the IP header and the TCP header */
+
+  tcpiplen = iplen + TCP_HDRLEN;
+
   /* Get the size of the link layer header, the IP header, and the TCP header */
 
   hdrlen = tcpiplen + NET_LL_HDRLEN(dev);
@@ -240,11 +251,13 @@ static void tcp_input(FAR struct net_driver_s *dev,
                   else if (opt == TCP_OPT_MSS &&
                           dev->d_buf[hdrlen + 1 + i] == TCP_OPT_MSS_LEN)
                     {
+                      uint16_t tcp_mss = TCP_MSS(dev, iplen);
+
                       /* An MSS option with the right option length. */
 
                       tmp16 = ((uint16_t)dev->d_buf[hdrlen + 2 + i] << 8) |
                                (uint16_t)dev->d_buf[hdrlen + 3 + i];
-                      conn->mss = tmp16 > TCP_MSS(dev) ? TCP_MSS(dev) : tmp16;
+                      conn->mss = tmp16 > tcp_mss ? tcp_mss : tmp16;
 
                       /* And we are done processing options. */
 
@@ -326,10 +339,10 @@ found:
 
   /* d_len will contain the length of the actual TCP data. This is
    * calculated by subtracting the length of the TCP header (in
-   * len) and the length of the IP header (20 bytes).
+   * len) and the length of the IP header.
    */
 
-  dev->d_len -= (len + IPv4_HDRLEN);
+  dev->d_len -= (len + iplen);
 
   /* First, check if the sequence number of the incoming packet is
    * what we're expecting next. If not, we send out an ACK with the
@@ -530,12 +543,14 @@ found:
                     else if (opt == TCP_OPT_MSS &&
                               dev->d_buf[hdrlen + 1 + i] == TCP_OPT_MSS_LEN)
                       {
+                        uint16_t tcp_mss = TCP_MSS(dev, iplen);
+
                         /* An MSS option with the right option length. */
 
                         tmp16 =
                           (dev->d_buf[hdrlen + 2 + i] << 8) |
                           dev->d_buf[hdrlen + 3 + i];
-                        conn->mss = tmp16 > TCP_MSS(dev) ? TCP_MSS(dev) : tmp16;
+                        conn->mss = tmp16 > tcp_mss ? tcp_mss : tmp16;
 
                         /* And we are done processing options. */
 
@@ -697,7 +712,8 @@ found:
          * When the application is called, the d_len field
          * contains the length of the incoming data. The application can
          * access the incoming data through the global pointer
-         * d_appdata, which usually points hdrlen bytes into the d_buf array.
+         * d_appdata, which usually points hdrlen bytes into the d_buf
+         * array.
          *
          * If the application wishes to send any data, this data should be
          * put into the d_appdata and the length of the data should be
@@ -871,8 +887,7 @@ drop:
 #ifdef CONFIG_NET_IPv4
 void tcp_ipv4_input(FAR struct net_driver_s *dev)
 {
-  unsigned int offset = IPv4_HDRLEN + NET_LL_HDRLEN(dev);
-  tcp_input(dev, (FAR struct tcp_hdr_s *)&dev->d_buf[offset], IPv4TCP_HDRLEN);
+  tcp_input(dev, IPv4_HDRLEN);
 }
 #endif
 
@@ -896,8 +911,7 @@ void tcp_ipv4_input(FAR struct net_driver_s *dev)
 #ifdef CONFIG_NET_IPv6
 void tcp_ipv6_input(FAR struct net_driver_s *dev)
 {
-  unsigned int offset = IPv6_HDRLEN + NET_LL_HDRLEN(dev);
-  tcp_input(dev, (FAR struct tcp_hdr_s *)&dev->d_buf[offset], IPv6TCP_HDRLEN);
+  tcp_input(dev, IPv6_HDRLEN);
 }
 #endif
 
diff --git a/nuttx/net/tcp/tcp_send.c b/nuttx/net/tcp/tcp_send.c
index 1a70b6ab6..5c23b657f 100644
--- a/nuttx/net/tcp/tcp_send.c
+++ b/nuttx/net/tcp/tcp_send.c
@@ -351,6 +351,7 @@ void tcp_ack(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn,
              uint8_t ack)
 {
   struct tcp_iphdr_s *pbuf = BUF;
+  uint16_t tcp_mss = TCP_IPv4_MSS(dev);
 
   /* Save the ACK bits */
 
@@ -360,8 +361,8 @@ void tcp_ack(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn,
 
   pbuf->optdata[0] = TCP_OPT_MSS;
   pbuf->optdata[1] = TCP_OPT_MSS_LEN;
-  pbuf->optdata[2] = TCP_MSS(dev) / 256;
-  pbuf->optdata[3] = TCP_MSS(dev) & 255;
+  pbuf->optdata[2] = tcp_mss >> 8;
+  pbuf->optdata[3] = tcp_mss & 0xff;
   dev->d_len       = IPv4TCP_HDRLEN + TCP_OPT_MSS_LEN;
   pbuf->tcpoffset  = ((TCP_HDRLEN + TCP_OPT_MSS_LEN) / 4) << 4;
 
diff --git a/nuttx/net/udp/udp_input.c b/nuttx/net/udp/udp_input.c
index d53b9185c..9062b6dd5 100644
--- a/nuttx/net/udp/udp_input.c
+++ b/nuttx/net/udp/udp_input.c
@@ -93,10 +93,11 @@
  *
  ****************************************************************************/
 
-static int udp_input(FAR struct net_driver_s *dev, FAR struct udp_hdr_s *udp,
-                     unsigned int udpiplen)
+static int udp_input(FAR struct net_driver_s *dev, unsigned int iplen)
 {
+  FAR struct udp_hdr_s *udp;
   FAR struct udp_conn_s *conn;
+  unsigned int udpiplen;
   unsigned int hdrlen;
   int ret = OK;
 
@@ -106,17 +107,27 @@ static int udp_input(FAR struct net_driver_s *dev, FAR struct udp_hdr_s *udp,
   g_netstats.udp.recv++;
 #endif
 
-  /* UDP processing is really just a hack. We don't do anything to the UDP/IP
-   * headers, but let the UDP application do all the hard work. If the
-   * application sets d_sndlen, it has a packet to send.
+  /* Get a pointer to the UDP header.  The UDP header lies just after the
+   * the link layer header and the IP header.
    */
 
-  dev->d_len -= udpiplen;
+  udp = (FAR struct udp_hdr_s *)&dev->d_buf[iplen + NET_LL_HDRLEN(dev)];
+
+  /* Get the size of the IP header and the UDP header */
+
+  udpiplen = iplen + UDP_HDRLEN;
 
   /* Get the size of the link layer header, the IP header, and the UDP header */
 
   hdrlen = udpiplen + NET_LL_HDRLEN(dev);
 
+  /* UDP processing is really just a hack. We don't do anything to the UDP/IP
+   * headers, but let the UDP application do all the hard work. If the
+   * application sets d_sndlen, it has a packet to send.
+   */
+
+  dev->d_len -= udpiplen;
+
 #ifdef CONFIG_NET_UDP_CHECKSUMS
   dev->d_appdata = &dev->d_buf[hdrlen];
 
@@ -219,9 +230,7 @@ static int udp_input(FAR struct net_driver_s *dev, FAR struct udp_hdr_s *udp,
 #ifdef CONFIG_NET_IPv4
 int udp_ipv4_input(FAR struct net_driver_s *dev)
 {
-  unsigned int offset = IPv4_HDRLEN + NET_LL_HDRLEN(dev);
-  return udp_input(dev, (FAR struct udp_hdr_s *)&dev->d_buf[offset],
-                   IPv4UDP_HDRLEN);
+  return udp_input(dev, IPv4_HDRLEN);
 }
 #endif
 
@@ -247,9 +256,7 @@ int udp_ipv4_input(FAR struct net_driver_s *dev)
 #ifdef CONFIG_NET_IPv6
 int udp_ipv6_input(FAR struct net_driver_s *dev)
 {
-  unsigned int offset = IPv6_HDRLEN + NET_LL_HDRLEN(dev);
-  return udp_input(dev, (FAR struct udp_hdr_s *)&dev->d_buf[offset],
-                   IPv6UDP_HDRLEN);
+  return udp_input(dev, IPv6_HDRLEN);
 }
 #endif