Fix an error in the handling of TCP/IP sequence numbers

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@2392 42af7a65-404d-4744-a932-0658087f49c3

7 files changed, 208 insertions, 102 deletions

diff --git a/nuttx/net/send.c b/nuttx/net/send.c
index b31723293..edb3d359a 100644
--- a/nuttx/net/send.c
+++ b/nuttx/net/send.c
@@ -88,54 +88,6 @@ struct send_s
  ****************************************************************************/
 
 /****************************************************************************
- * Function: send_getisn
- *
- * Description:
- *   Get the next initial sequence number from the connection stucture
- *
- * Parameters:
- *   conn     The connection structure associated with the socket
- *
- * Returned Value:
- *   None
- *
- * Assumptions:
- *   Running at the interrupt level
- *
- ****************************************************************************/
-
-static uint32_t send_getisn(struct uip_conn *conn)
-{
-   uint32_t tmp;
-   memcpy(&tmp, conn->snd_nxt, 4);
-   return ntohl(tmp);
-}
-
-/****************************************************************************
- * Function: send_getackno
- *
- * Description:
- *   Extract the current acknowledgement sequence number from the incoming packet
- *
- * Parameters:
- *   dev - The sructure of the network driver that caused the interrupt
- *
- * Returned Value:
- *   None
- *
- * Assumptions:
- *   Running at the interrupt level
- *
- ****************************************************************************/
-
-static uint32_t send_getackno(struct uip_driver_s *dev)
-{
-   uint32_t tmp;
-   memcpy(&tmp, TCPBUF->ackno, 4);
-   return ntohl(tmp);
-}
-
-/****************************************************************************
  * Function: send_timeout
  *
  * Description:
@@ -216,7 +168,7 @@ static uint16_t send_interrupt(struct uip_driver_s *dev, void *pvconn,
        * is the number of bytes to be acknowledged.
        */
 
-      pstate->snd_acked = send_getackno(dev) - pstate->snd_isn;
+      pstate->snd_acked = uip_tcpgetsequence(TCPBUF->ackno) - pstate->snd_isn;
       nllvdbg("ACK: acked=%d sent=%d buflen=%d\n",
               pstate->snd_acked, pstate->snd_sent, pstate->snd_buflen);
 
@@ -259,7 +211,7 @@ static uint16_t send_interrupt(struct uip_driver_s *dev, void *pvconn,
     }
 
    /* Check if the outgoing packet is available (it may have been claimed
-    * by a sendto interrupt serving a different thread.
+    * by a sendto interrupt serving a different thread).
     */
 
 #if 0 /* We can't really support multiple senders on the same TCP socket */
@@ -289,6 +241,10 @@ static uint16_t send_interrupt(struct uip_driver_s *dev, void *pvconn,
           sndlen = uip_mss(conn);
         }
 
+      /* Set the sequence number for this packet */
+
+      uip_tcpsetsequence(conn->snd_nxt, pstate->snd_sent + pstate->snd_isn);
+
       /* Then send that amount of data */
 
       uip_send(dev, &pstate->snd_buffer[pstate->snd_sent], sndlen);
@@ -459,7 +415,7 @@ ssize_t send(int sockfd, const void *buf, size_t len, int flags)
         {
           /* Get the initial sequence number that will be used */
 
-          state.snd_isn         = send_getisn(conn); /* Initial sequence number */
+          state.snd_isn         = uip_tcpgetsequence(conn->snd_nxt);
 
           /* Update the initial time for calculating timeouts */
 
diff --git a/nuttx/net/uip/Make.defs b/nuttx/net/uip/Make.defs
index e67c73243..ce102ff62 100644
--- a/nuttx/net/uip/Make.defs
+++ b/nuttx/net/uip/Make.defs
@@ -51,7 +51,7 @@ endif
 
 ifeq ($(CONFIG_NET_TCP),y)
 
-UIP_CSRCS += uip_tcpconn.c uip_tcppoll.c uip_tcptimer.c uip_tcpsend.c \
+UIP_CSRCS += uip_tcpconn.c uip_tcpseqno.c uip_tcppoll.c uip_tcptimer.c uip_tcpsend.c \
              uip_tcpinput.c uip_tcpappsend.c uip_listen.c uip_tcpcallback.c \
              uip_tcpreadahead.c uip_tcpbacklog.c
 
diff --git a/nuttx/net/uip/uip_chksum.c b/nuttx/net/uip/uip_chksum.c
index b35808e8a..538e56a04 100644
--- a/nuttx/net/uip/uip_chksum.c
+++ b/nuttx/net/uip/uip_chksum.c
@@ -148,7 +148,7 @@ static uint16_t uip_icmp6chksum(struct uip_driver_s *dev)
 /* Calculate the Internet checksum over a buffer. */
 
 #if !UIP_ARCH_ADD32
-static void uip_carry32(uint8_t *sum, uint16_t op16)
+static inline void uip_carry32(uint8_t *sum, uint16_t op16)
 {
   if (sum[2] < (op16 >> 8))
     {
@@ -173,17 +173,6 @@ static void uip_carry32(uint8_t *sum, uint16_t op16)
     }
 }
 
-void uip_add32(const uint8_t *op32, uint16_t op16, uint8_t *sum)
-{
-  /* op32 and the sum are in network order (big-endian); op16 is host order. */
-
-  sum[3] = op32[3] + (op16 & 0xff);
-  sum[2] = op32[2] + (op16 >> 8);
-  sum[1] = op32[1];
-  sum[0] = op32[0];
-  uip_carry32(sum, op16);
-}
-
 void uip_incr32(uint8_t *op32, uint16_t op16)
 {
   op32[3] += (op16 & 0xff);
diff --git a/nuttx/net/uip/uip_internal.h b/nuttx/net/uip/uip_internal.h
index 948a85e51..65928e01a 100644
--- a/nuttx/net/uip/uip_internal.h
+++ b/nuttx/net/uip/uip_internal.h
@@ -110,6 +110,13 @@ EXTERN struct uip_conn *uip_tcpactive(struct uip_tcpip_hdr *buf);
 EXTERN struct uip_conn *uip_nexttcpconn(struct uip_conn *conn);
 EXTERN struct uip_conn *uip_tcplistener(uint16_t portno);
 EXTERN struct uip_conn *uip_tcpaccept(struct uip_tcpip_hdr *buf);
+
+/* Defined in uip_tcpseqno.c ************************************************/
+
+EXTERN void uip_tcpsetsequence(FAR uint8_t *seqno, uint32_t value);
+EXTERN uint32_t uip_tcpgetsequence(FAR uint8_t *seqno);
+EXTERN uint32_t uip_tcpaddsequence(FAR uint8_t *seqno, uint16_t len);
+EXTERN void uip_tcpinitsequence(FAR uint8_t *seqno);
 EXTERN void uip_tcpnextsequence(void);
 
 /* Defined in uip_tcppoll.c *************************************************/
diff --git a/nuttx/net/uip/uip_tcpconn.c b/nuttx/net/uip/uip_tcpconn.c
index 323640812..a16950ddd 100644
--- a/nuttx/net/uip/uip_tcpconn.c
+++ b/nuttx/net/uip/uip_tcpconn.c
@@ -85,10 +85,6 @@ static dq_queue_t g_active_tcp_connections;
 
 static uint16_t g_last_tcp_port;
 
-/* g_tcp_sequence[] is used to generate TCP sequence numbers */
-
-static uint8_t g_tcp_sequence[4];
-
 /****************************************************************************
  * Private Functions
  ****************************************************************************/
@@ -469,7 +465,7 @@ struct uip_conn *uip_tcpaccept(struct uip_tcpip_hdr *buf)
       uip_ipaddr_copy(conn->ripaddr, uip_ip4addr_conv(buf->srcipaddr));
       conn->tcpstateflags = UIP_SYN_RCVD;
 
-      memcpy(conn->snd_nxt, g_tcp_sequence, 4);
+      uip_tcpinitsequence(conn->snd_nxt);
       conn->len           = 1;
 
       /* rcv_nxt should be the seqno from the incoming packet + 1. */
@@ -492,33 +488,6 @@ struct uip_conn *uip_tcpaccept(struct uip_tcpip_hdr *buf)
 }
 
 /****************************************************************************
- * Name: uip_tcpnextsequence()
- *
- * Description:
- *   Increment the TCP/IP sequence number
- *
- * Assumptions:
- *   This function is called from the interrupt level
- *
- ****************************************************************************/
-
-void uip_tcpnextsequence(void)
-{
-  /* This inplements a byte-by-byte big-endian increment */
-
-  if (++g_tcp_sequence[3] == 0)
-    {
-      if (++g_tcp_sequence[2] == 0)
-        {
-          if (++g_tcp_sequence[1] == 0)
-            {
-              ++g_tcp_sequence[0];
-            }
-        }
-    }
-}
-
-/****************************************************************************
  * Name: uip_tcpbind()
  *
  * Description:
@@ -626,7 +595,7 @@ int uip_tcpconnect(struct uip_conn *conn, const struct sockaddr_in *addr)
   /* Initialize and return the connection structure, bind it to the port number */
 
   conn->tcpstateflags = UIP_SYN_SENT;
-  memcpy(conn->snd_nxt, g_tcp_sequence, 4);
+  uip_tcpinitsequence(conn->snd_nxt);
 
   conn->initialmss = conn->mss = UIP_TCP_MSS;
   conn->len        = 1;    /* TCP length of the SYN is one. */
diff --git a/nuttx/net/uip/uip_tcpinput.c b/nuttx/net/uip/uip_tcpinput.c
index e3a8196f6..f882ed1b9 100644
--- a/nuttx/net/uip/uip_tcpinput.c
+++ b/nuttx/net/uip/uip_tcpinput.c
@@ -328,16 +328,28 @@ found:
 
   if ((pbuf->flags & TCP_ACK) && uip_outstanding(conn))
     {
-      /* Temporary variables. */
+      uint32_t seqno;
+      uint32_t ackno;
 
-      uint8_t acc32[4];
-      uip_add32(conn->snd_nxt, conn->len, acc32);
+      /* The next sequence number is equal to the current sequence
+       * number (snd_nxt) plus the size of the oustanding data (len).
+       */
+
+      seqno = uip_tcpaddsequence(conn->snd_nxt, conn->len);
+
+      /* Check if all of the outstanding bytes have been acknowledged. For
+       * a "generic" send operation, this should always be true.  However,
+       * the send() API sends data ahead when it can without waiting for
+       * the ACK.  In this case, the 'ackno' could be less than then the
+       * new sequence number.
+       */
 
-      if (memcmp(pbuf->ackno, acc32, 4) == 0)
+      ackno = uip_tcpgetsequence(pbuf->ackno);
+      if (ackno <= seqno)
         {
           /* Update sequence number. */
 
-          memcpy(conn->snd_nxt, acc32, 4);
+          uip_tcpsetsequence(conn->snd_nxt, seqno);
 
           /* Do RTT estimation, unless we have done retransmissions. */
 
diff --git a/nuttx/net/uip/uip_tcpseqno.c b/nuttx/net/uip/uip_tcpseqno.c
new file mode 100755
index 000000000..8c19eb257
--- /dev/null
+++ b/nuttx/net/uip/uip_tcpseqno.c
@@ -0,0 +1,173 @@
+/****************************************************************************
+ * net/uip/uip_tcpseqno.c
+ *
+ *   Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Large parts of this file were leveraged from uIP logic:
+ *
+ *   Copyright (c) 2001-2003, Adam Dunkels.
+ *   All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior
+ *    written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Compilation Switches
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#if defined(CONFIG_NET) && defined(CONFIG_NET_TCP)
+
+#include <stdint.h>
+#include <debug.h>
+
+#include <net/uip/uipopt.h>
+#include <net/uip/uip.h>
+#include <net/uip/uip-arch.h>
+
+#include "uip_internal.h"
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/* g_tcpsequence is used to generate initial TCP sequence numbers */
+
+static uint32_t g_tcpsequence;
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: uip_tcpsetsequence
+ *
+ * Description:
+ *   Set the TCP/IP sequence number
+ *
+ * Assumptions:
+ *   This function may called from the interrupt level
+ *
+ ****************************************************************************/
+
+void uip_tcpsetsequence(FAR uint8_t *seqno, uint32_t value)
+{
+  /* Copy the sequence number in network (big-endian) order */
+
+  *seqno++ =  value >> 24;
+  *seqno++ = (value >> 16) & 0xff;
+  *seqno++ = (value >>  8) & 0xff;
+  *seqno   =  value        & 0xff;
+}
+
+/****************************************************************************
+ * Name: uip_tcpgetsequence
+ *
+ * Description:
+ *   Get the TCP/IP sequence number
+ *
+ * Assumptions:
+ *   This function may called from the interrupt level
+ *
+ ****************************************************************************/
+
+uint32_t uip_tcpgetsequence(FAR uint8_t *seqno)
+{
+  uint32_t value;
+ 
+  /* Combine the sequence number from network (big-endian) order */
+
+   value = (uint32_t)seqno[0] << 24 |
+           (uint32_t)seqno[1] << 16 |
+           (uint32_t)seqno[2] <<  8 |
+           (uint32_t)seqno[3];
+   return value;
+}
+
+/****************************************************************************
+ * Name: uip_tcpaddsequence
+ *
+ * Description:
+ *   Add the length to get the next TCP sequence number.
+ *
+ * Assumptions:
+ *   This function may called from the interrupt level
+ *
+ ****************************************************************************/
+
+uint32_t uip_tcpaddsequence(FAR uint8_t *seqno, uint16_t len)
+{
+  return uip_tcpgetsequence(seqno) + (uint32_t)len;
+}
+
+/****************************************************************************
+ * Name: uip_tcpinitsequence
+ *
+ * Description:
+ *   Set the (initial) the TCP/IP sequence number when a TCP connection is
+ *   established.
+ *
+ * Assumptions:
+ *   This function may called from the interrupt level
+ *
+ ****************************************************************************/
+
+void uip_tcpinitsequence(FAR uint8_t *seqno)
+{
+  uip_tcpsetsequence(seqno, g_tcpsequence);
+}
+
+/****************************************************************************
+ * Name: uip_tcpnextsequence
+ *
+ * Description:
+ *   Increment the TCP/IP sequence number
+ *
+ * Assumptions:
+ *   This function is called from the interrupt level
+ *
+ ****************************************************************************/
+
+void uip_tcpnextsequence(void)
+{
+  g_tcpsequence++;
+}
+
+#endif /* CONFIG_NET && CONFIG_NET_TCP */