nes-proj/os/net/ipv6/uipbuf.c

72 lines
2.6 KiB
C

/*
* Copyright (c) 2017, RISE SICS
* 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 authors may not be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``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.
*
*
*/
#include "contiki.h"
#include "uip.h"
/* Get the next header given the buffer - start indicates that this is
start of the IPv6 header - needs to be set to 0 when in an ext hdr */
uint8_t*
uipbuf_get_next_header(uint8_t *buffer, uint16_t size, uint8_t *protocol, uint8_t start)
{
int ext_len = 0;
struct uip_ip_hdr *ipbuf = (struct uip_ip_hdr *) buffer;
struct uip_ext_hdr *ext = NULL;
if(start) {
/* protocol in the IP buffer */
*protocol = ipbuf->proto;
return buffer + UIP_IPH_LEN;
} else {
/* protocol in the Ext hdr */
ext = (struct uip_ext_hdr *) buffer;
*protocol = ext->next;
/* This is just an ext header */
ext_len = (ext->len << 3) + 8;
return buffer + ext_len;
}
}
/* Get the final header given the buffer - that is assumed to be at start
of an IPv6 header */
uint8_t*
uipbuf_get_last_header(uint8_t *buffer, uint16_t size, uint8_t *protocol)
{
uint8_t *nbuf;
nbuf = uipbuf_get_next_header(buffer, size, protocol, 1);
while(uip_is_proto_ext_hdr(*protocol)) {
/* send in and move beyond the ext hdr */
nbuf = uipbuf_get_next_header(nbuf, size - (nbuf - buffer), protocol, 0);
}
return nbuf;
}