kopia lustrzana https://github.com/F5OEO/tstools
50 wiersze
1022 B
C
50 wiersze
1022 B
C
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/* ethernet.c */
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/*
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* Routines for taking ethernet packets apart.
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*/
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#include "ethernet.h"
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#include <string.h>
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#include "misc_fns.h"
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int ethernet_packet_from_pcap(pcaprec_hdr_t *hdr,
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const uint8_t *data,
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const uint32_t len,
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ethernet_packet_t *pkt,
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uint32_t *out_st,
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uint32_t *out_len)
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{
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// 14 bytes of src,dest,type ..
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if (len < 14)
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{
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return ETHERNET_ERR_PKT_TOO_SHORT;
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}
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// PCap doesn't store CRCs - it stores [dst] [src] [type]
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memcpy(pkt->dst_addr, &data[0], 6);
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memcpy(pkt->src_addr, &data[6], 6);
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// Type/Length is big-endian.
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pkt->typeorlen = uint_16_be(&data[12]);
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// 0x5DC is the maximum frame length in IEEE 802.3 - anything
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// above that here is a type.
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//
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// Length is just the data length.
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if (pkt->typeorlen <= 0x5DC)
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{
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(*out_len) = pkt->typeorlen;
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}
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else
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{
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// pcap doesn't store the checksum or pad ..
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(*out_len) = len - 14;
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}
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(*out_st) = 14;
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return 0;
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}
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/* End file */
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