You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
137 lines
4.6 KiB
137 lines
4.6 KiB
/*
|
|
* Copyright (c) 2004, Swedish Institute of Computer Science.
|
|
* 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. Neither the name of the Institute nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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.
|
|
*
|
|
* This file is part of the uIP TCP/IP stack
|
|
*
|
|
* Author: Adam Dunkels <adam@sics.se>
|
|
*
|
|
* $Id: uip-split.c,v 1.2 2006/06/12 08:00:30 adam Exp $
|
|
*/
|
|
|
|
#include <string.h>
|
|
|
|
#include "uip-split.h"
|
|
#include "uip.h"
|
|
#include "uip-fw.h"
|
|
#include "uip_arch.h"
|
|
|
|
|
|
|
|
#define BUF ((struct uip_tcpip_hdr *)&uip_buf[UIP_LLH_LEN])
|
|
|
|
/*-----------------------------------------------------------------------------*/
|
|
void
|
|
uip_split_output(void)
|
|
{
|
|
u16_t tcplen, len1, len2;
|
|
|
|
/* We only try to split maximum sized TCP segments. */
|
|
if(BUF->proto == UIP_PROTO_TCP &&
|
|
uip_len == UIP_BUFSIZE - UIP_LLH_LEN) {
|
|
|
|
tcplen = uip_len - UIP_TCPIP_HLEN;
|
|
/* Split the segment in two. If the original packet length was
|
|
odd, we make the second packet one byte larger. */
|
|
len1 = len2 = tcplen / 2;
|
|
if(len1 + len2 < tcplen) {
|
|
++len2;
|
|
}
|
|
|
|
/* Create the first packet. This is done by altering the length
|
|
field of the IP header and updating the checksums. */
|
|
uip_len = len1 + UIP_TCPIP_HLEN;
|
|
#if UIP_CONF_IPV6
|
|
/* For IPv6, the IP length field does not include the IPv6 IP header
|
|
length. */
|
|
BUF->len[0] = ((uip_len - UIP_IPH_LEN) >> 8);
|
|
BUF->len[1] = ((uip_len - UIP_IPH_LEN) & 0xff);
|
|
#else /* UIP_CONF_IPV6 */
|
|
BUF->len[0] = uip_len >> 8;
|
|
BUF->len[1] = uip_len & 0xff;
|
|
#endif /* UIP_CONF_IPV6 */
|
|
|
|
/* Recalculate the TCP checksum. */
|
|
BUF->tcpchksum = 0;
|
|
BUF->tcpchksum = ~(uip_tcpchksum());
|
|
|
|
#if !UIP_CONF_IPV6
|
|
/* Recalculate the IP checksum. */
|
|
BUF->ipchksum = 0;
|
|
BUF->ipchksum = ~(uip_ipchksum());
|
|
#endif /* UIP_CONF_IPV6 */
|
|
|
|
/* Transmit the first packet. */
|
|
/* uip_fw_output();*/
|
|
tcpip_output();
|
|
|
|
/* Now, create the second packet. To do this, it is not enough to
|
|
just alter the length field, but we must also update the TCP
|
|
sequence number and point the uip_appdata to a new place in
|
|
memory. This place is detemined by the length of the first
|
|
packet (len1). */
|
|
uip_len = len2 + UIP_TCPIP_HLEN;
|
|
#if UIP_CONF_IPV6
|
|
/* For IPv6, the IP length field does not include the IPv6 IP header
|
|
length. */
|
|
BUF->len[0] = ((uip_len - UIP_IPH_LEN) >> 8);
|
|
BUF->len[1] = ((uip_len - UIP_IPH_LEN) & 0xff);
|
|
#else /* UIP_CONF_IPV6 */
|
|
BUF->len[0] = uip_len >> 8;
|
|
BUF->len[1] = uip_len & 0xff;
|
|
#endif /* UIP_CONF_IPV6 */
|
|
|
|
/* uip_appdata += len1;*/
|
|
memcpy(uip_appdata, (u8_t *)uip_appdata + len1, len2);
|
|
|
|
uip_add32(BUF->seqno, len1);
|
|
BUF->seqno[0] = uip_acc32[0];
|
|
BUF->seqno[1] = uip_acc32[1];
|
|
BUF->seqno[2] = uip_acc32[2];
|
|
BUF->seqno[3] = uip_acc32[3];
|
|
|
|
/* Recalculate the TCP checksum. */
|
|
BUF->tcpchksum = 0;
|
|
BUF->tcpchksum = ~(uip_tcpchksum());
|
|
|
|
#if !UIP_CONF_IPV6
|
|
/* Recalculate the IP checksum. */
|
|
BUF->ipchksum = 0;
|
|
BUF->ipchksum = ~(uip_ipchksum());
|
|
#endif /* UIP_CONF_IPV6 */
|
|
|
|
/* Transmit the second packet. */
|
|
/* uip_fw_output();*/
|
|
tcpip_output();
|
|
} else {
|
|
/* uip_fw_output();*/
|
|
tcpip_output();
|
|
}
|
|
|
|
}
|
|
/*-----------------------------------------------------------------------------*/
|