[apple/network_cmds.git] / tcpdump.tproj / print-gre.c

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
 * Reserved.  This file contains Original Code and/or Modifications of
 * Original Code as defined in and that are subject to the Apple Public
 * Source License Version 1.0 (the 'License').  You may not use this file
 * except in compliance with the License.  Please obtain a copy of the
 * License at http://www.apple.com/publicsource and read it before using
 * this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License."
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) 1996
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Lawrence Berkeley Laboratory,
 * Berkeley, CA.  The name of the University may not be used to
 * endorse or promote products derived from this software without
 * specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Initial contribution from John Hawkinson <jhawk@bbnplanet.com>
 *
 * This module implements support for decoding GRE (Generic Routing
 * Encapsulation) tunnels; they're documented in RFC1701 and RFC1702.
 * This code only supports the IP encapsulation thereof.
 */

#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /cvs/Darwin/Commands/NeXT/network_cmds/tcpdump.tproj/print-gre.c,v 1.1.1.1 1999/05/02 03:58:33 wsanchez Exp $";
#endif

#include <sys/param.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>

#include <netdb.h>
#include <stdio.h>

#include "interface.h"
#include "addrtoname.h"
#include "extract.h"		/* must come after interface.h */

#define GRE_SIZE (20)

struct gre {
	u_short flags;
	u_short proto;
	union {
		struct gre_ckof {
			u_short cksum;
			u_short offset;
		}        gre_ckof;
		u_int32_t key;
		u_int32_t seq;
	}     gre_void1;
	union {
		u_int32_t key;
		u_int32_t seq;
		u_int32_t routing;
	}     gre_void2;
	union {
		u_int32_t seq;
		u_int32_t routing;
	}     gre_void3;
	union {
		u_int32_t routing;
	}     gre_void4;
};

#define GRE_CP		0x8000	/* Checksum Present */
#define GRE_RP		0x4000	/* Routing Present */
#define GRE_KP		0x2000	/* Key Present */
#define GRE_SP		0x1000	/* Sequence Present */


#define GREPROTO_IP	0x0800


/*
 * Deencapsulate and print a GRE-tunneled IP datagram
 */
void
gre_print(const u_char *bp, u_int length)
{
	const u_char *cp = bp + 4;
	const struct gre *gre;
	u_short flags, proto;

	gre = (const struct gre *)bp;

	if (length < GRE_SIZE) {
		goto trunc;
	}
	flags = EXTRACT_16BITS(&gre->flags);
	proto = EXTRACT_16BITS(&gre->proto);

	if (vflag) {
		/* Decode the flags */
		putchar('[');
		if (flags & GRE_CP)
			putchar('C');
		if (flags & GRE_RP)
			putchar('R');
		if (flags & GRE_KP)
			putchar('K');
		if (flags & GRE_SP)
			putchar('S');
		fputs("] ", stdout);
	}
	/* Checksum & Offset are present */
	if ((flags & GRE_CP) | (flags & GRE_RP))
		cp += 4;

	/* We don't support routing fields (variable length) now. Punt. */
	if (flags & GRE_RP)
		return;

	if (flags & GRE_KP)
		cp += 4;
	if (flags & GRE_SP)
		cp += 4;

	switch (proto) {

	case GREPROTO_IP:
		ip_print(cp, length - ((cp - bp) / sizeof(u_char)));
		break;

	default:
		printf("gre-proto-0x%04X", proto);
		break;
	}
	return;

trunc:
	fputs("[|gre]", stdout);

}
Commit	Line	Data
b7080c8e A	1	/*
	2	* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	6	* "Portions Copyright (c) 1999 Apple Computer, Inc. All Rights
	7	* Reserved. This file contains Original Code and/or Modifications of
	8	* Original Code as defined in and that are subject to the Apple Public
	9	* Source License Version 1.0 (the 'License'). You may not use this file
	10	* except in compliance with the License. Please obtain a copy of the
	11	* License at http://www.apple.com/publicsource and read it before using
	12	* this file.
	13	*
	14	* The Original Code and all software distributed under the License are
	15	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	16	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	17	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	18	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	19	* License for the specific language governing rights and limitations
	20	* under the License."
	21	*
	22	* @APPLE_LICENSE_HEADER_END@
	23	*/
	24	/*
	25	* Copyright (c) 1996
	26	* The Regents of the University of California. All rights reserved.
	27	*
	28	* Redistribution and use in source and binary forms are permitted
	29	* provided that the above copyright notice and this paragraph are
	30	* duplicated in all such forms and that any documentation,
	31	* advertising materials, and other materials related to such
	32	* distribution and use acknowledge that the software was developed
	33	* by the University of California, Lawrence Berkeley Laboratory,
	34	* Berkeley, CA. The name of the University may not be used to
	35	* endorse or promote products derived from this software without
	36	* specific prior written permission.
	37	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
	38	* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
	39	* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
	40	*
	41	* Initial contribution from John Hawkinson <jhawk@bbnplanet.com>
	42	*
	43	* This module implements support for decoding GRE (Generic Routing
	44	* Encapsulation) tunnels; they're documented in RFC1701 and RFC1702.
	45	* This code only supports the IP encapsulation thereof.
	46	*/
	47
	48	#ifndef lint
	49	static const char rcsid[] =
	50	"@(#) $Header: /cvs/Darwin/Commands/NeXT/network_cmds/tcpdump.tproj/print-gre.c,v 1.1.1.1 1999/05/02 03:58:33 wsanchez Exp $";
	51	#endif
	52
	53	#include <sys/param.h>
	54	#include <sys/time.h>
	55	#include <sys/uio.h>
	56	#include <sys/socket.h>
	57
	58	#include <netinet/in.h>
	59	#include <netinet/in_systm.h>
	60	#include <netinet/ip.h>
	61
	62	#include <netdb.h>
	63	#include <stdio.h>
	64
65	#include "interface.h"
66	#include "addrtoname.h"
67	#include "extract.h" /* must come after interface.h */
68
69	#define GRE_SIZE (20)
70
71	struct gre {
72	u_short flags;
73	u_short proto;
74	union {
75	struct gre_ckof {
76	u_short cksum;
77	u_short offset;
78	} gre_ckof;
79	u_int32_t key;
80	u_int32_t seq;
81	} gre_void1;
82	union {
83	u_int32_t key;
84	u_int32_t seq;
85	u_int32_t routing;
86	} gre_void2;
87	union {
88	u_int32_t seq;
89	u_int32_t routing;
90	} gre_void3;
91	union {
92	u_int32_t routing;
93	} gre_void4;
94	};
95
96	#define GRE_CP 0x8000 /* Checksum Present */
97	#define GRE_RP 0x4000 /* Routing Present */
98	#define GRE_KP 0x2000 /* Key Present */
99	#define GRE_SP 0x1000 /* Sequence Present */
100
101
102	#define GREPROTO_IP 0x0800
103
104
105	/*
106	* Deencapsulate and print a GRE-tunneled IP datagram
107	*/
108	void
109	gre_print(const u_char *bp, u_int length)
110	{
111	const u_char *cp = bp + 4;
112	const struct gre *gre;
113	u_short flags, proto;
114
115	gre = (const struct gre *)bp;
116
117	if (length < GRE_SIZE) {
118	goto trunc;
119	}
120	flags = EXTRACT_16BITS(&gre->flags);
121	proto = EXTRACT_16BITS(&gre->proto);
122
123	if (vflag) {
124	/* Decode the flags */
125	putchar('[');
126	if (flags & GRE_CP)
127	putchar('C');
128	if (flags & GRE_RP)
129	putchar('R');
130	if (flags & GRE_KP)
131	putchar('K');
132	if (flags & GRE_SP)
133	putchar('S');
134	fputs("] ", stdout);
135	}
136	/* Checksum & Offset are present */
137	if ((flags & GRE_CP) \| (flags & GRE_RP))
138	cp += 4;
139
140	/* We don't support routing fields (variable length) now. Punt. */
141	if (flags & GRE_RP)
142	return;
143
144	if (flags & GRE_KP)
145	cp += 4;
146	if (flags & GRE_SP)
147	cp += 4;
148
149	switch (proto) {
150
151	case GREPROTO_IP:
152	ip_print(cp, length - ((cp - bp) / sizeof(u_char)));
153	break;
154
155	default:
156	printf("gre-proto-0x%04X", proto);
157	break;
158	}
159	return;
160
161	trunc:
162	fputs("[\|gre]", stdout);
163
164	}