F5OEO-tstools/ethernet.c

74 wiersze
1.9 KiB
C

/* ethernet.c */
/*
* Routines for taking ethernet packets apart.
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the MPEG TS, PS and ES tools.
*
* The Initial Developer of the Original Code is Amino Communications Ltd.
* Portions created by the Initial Developer are Copyright (C) 2008
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Richard Watts, Kynesim <rrw@kynesim.co.uk>
*
* ***** END LICENSE BLOCK *****
*/
#include "ethernet.h"
#include <string.h>
#include "misc_fns.h"
int ethernet_packet_from_pcap(pcaprec_hdr_t *hdr,
const uint8_t *data,
const uint32_t len,
ethernet_packet_t *pkt,
uint32_t *out_st,
uint32_t *out_len)
{
// 14 bytes of src,dest,type ..
if (len < 14)
{
return ETHERNET_ERR_PKT_TOO_SHORT;
}
// PCap doesn't store CRCs - it stores [dst] [src] [type]
memcpy(pkt->dst_addr, &data[0], 6);
memcpy(pkt->src_addr, &data[6], 6);
// Type/Length is big-endian.
pkt->typeorlen = uint_16_be(&data[12]);
// 0x5DC is the maximum frame length in IEEE 802.3 - anything
// above that here is a type.
//
// Length is just the data length.
if (pkt->typeorlen <= 0x5DC)
{
(*out_len) = pkt->typeorlen;
}
else
{
// pcap doesn't store the checksum or pad ..
(*out_len) = len - 14;
}
(*out_st) = 14;
return 0;
}
/* End file */