xref: /freebsd-src/contrib/libpcap/pcap-util.h (revision afdbf109c6a661a729938f68211054a0a50d38ac)
16f9cba8fSJoseph Mingrone /*
26f9cba8fSJoseph Mingrone  * Copyright (c) 1993, 1994, 1995, 1996, 1997
36f9cba8fSJoseph Mingrone  *	The Regents of the University of California.  All rights reserved.
46f9cba8fSJoseph Mingrone  *
56f9cba8fSJoseph Mingrone  * Redistribution and use in source and binary forms, with or without
66f9cba8fSJoseph Mingrone  * modification, are permitted provided that: (1) source code distributions
76f9cba8fSJoseph Mingrone  * retain the above copyright notice and this paragraph in its entirety, (2)
86f9cba8fSJoseph Mingrone  * distributions including binary code include the above copyright notice and
96f9cba8fSJoseph Mingrone  * this paragraph in its entirety in the documentation or other materials
106f9cba8fSJoseph Mingrone  * provided with the distribution, and (3) all advertising materials mentioning
116f9cba8fSJoseph Mingrone  * features or use of this software display the following acknowledgement:
126f9cba8fSJoseph Mingrone  * ``This product includes software developed by the University of California,
136f9cba8fSJoseph Mingrone  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
146f9cba8fSJoseph Mingrone  * the University nor the names of its contributors may be used to endorse
156f9cba8fSJoseph Mingrone  * or promote products derived from this software without specific prior
166f9cba8fSJoseph Mingrone  * written permission.
176f9cba8fSJoseph Mingrone  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
186f9cba8fSJoseph Mingrone  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
196f9cba8fSJoseph Mingrone  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
206f9cba8fSJoseph Mingrone  *
216f9cba8fSJoseph Mingrone  * pcap-util.h - common code for various files
226f9cba8fSJoseph Mingrone  */
236f9cba8fSJoseph Mingrone 
246f9cba8fSJoseph Mingrone /*
256f9cba8fSJoseph Mingrone  * We use the "receiver-makes-right" approach to byte order;
266f9cba8fSJoseph Mingrone  * because time is at a premium when we are writing the file.
276f9cba8fSJoseph Mingrone  * In other words, the pcap_file_header and pcap_pkthdr,
286f9cba8fSJoseph Mingrone  * records are written in host byte order.
296f9cba8fSJoseph Mingrone  * Note that the bytes of packet data are written out in the order in
306f9cba8fSJoseph Mingrone  * which they were received, so multi-byte fields in packets are not
316f9cba8fSJoseph Mingrone  * written in host byte order, they're written in whatever order the
326f9cba8fSJoseph Mingrone  * sending machine put them in.
336f9cba8fSJoseph Mingrone  *
346f9cba8fSJoseph Mingrone  * We also use this for fixing up packet data headers from a remote
356f9cba8fSJoseph Mingrone  * capture, where the server may have a different byte order from the
366f9cba8fSJoseph Mingrone  * client.
376f9cba8fSJoseph Mingrone  *
386f9cba8fSJoseph Mingrone  * ntoh[ls] aren't sufficient because we might need to swap on a big-endian
396f9cba8fSJoseph Mingrone  * machine (if the file was written in little-end order).
406f9cba8fSJoseph Mingrone  */
416f9cba8fSJoseph Mingrone #define	SWAPLONG(y) \
426f9cba8fSJoseph Mingrone     (((((u_int)(y))&0xff)<<24) | \
436f9cba8fSJoseph Mingrone      ((((u_int)(y))&0xff00)<<8) | \
446f9cba8fSJoseph Mingrone      ((((u_int)(y))&0xff0000)>>8) | \
456f9cba8fSJoseph Mingrone      ((((u_int)(y))>>24)&0xff))
466f9cba8fSJoseph Mingrone #define	SWAPSHORT(y) \
476f9cba8fSJoseph Mingrone      ((u_short)(((((u_int)(y))&0xff)<<8) | \
486f9cba8fSJoseph Mingrone                 ((((u_int)(y))&0xff00)>>8)))
496f9cba8fSJoseph Mingrone 
50*afdbf109SJoseph Mingrone extern void pcapint_post_process(int linktype, int swapped,
516f9cba8fSJoseph Mingrone     struct pcap_pkthdr *hdr, u_char *data);
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