1/*
2 * Copyright (c) 1995, 1996, 1997
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 *
21 * Initial contribution from John Hawkinson (jhawk@mit.edu).
22 */
23
24#ifndef lint
25static const char rcsid[] _U_ =
26    "@(#) $Header: /tcpdump/master/tcpdump/print-krb.c,v 1.23 2003-11-16 09:36:26 guy Exp $";
27#endif
28
29#ifdef HAVE_CONFIG_H
30#include "config.h"
31#endif
32
33#include <tcpdump-stdinc.h>
34
35#include <stdio.h>
36
37#include "interface.h"
38#include "addrtoname.h"
39#include "extract.h"
40
41static const u_char *c_print(register const u_char *, register const u_char *);
42static const u_char *krb4_print_hdr(const u_char *);
43static void krb4_print(const u_char *);
44
45#define AUTH_MSG_KDC_REQUEST			1<<1
46#define AUTH_MSG_KDC_REPLY			2<<1
47#define AUTH_MSG_APPL_REQUEST			3<<1
48#define AUTH_MSG_APPL_REQUEST_MUTUAL		4<<1
49#define AUTH_MSG_ERR_REPLY			5<<1
50#define AUTH_MSG_PRIVATE			6<<1
51#define AUTH_MSG_SAFE				7<<1
52#define AUTH_MSG_APPL_ERR			8<<1
53#define AUTH_MSG_DIE				63<<1
54
55#define KERB_ERR_OK				0
56#define KERB_ERR_NAME_EXP			1
57#define KERB_ERR_SERVICE_EXP			2
58#define KERB_ERR_AUTH_EXP			3
59#define KERB_ERR_PKT_VER			4
60#define KERB_ERR_NAME_MAST_KEY_VER		5
61#define KERB_ERR_SERV_MAST_KEY_VER		6
62#define KERB_ERR_BYTE_ORDER			7
63#define KERB_ERR_PRINCIPAL_UNKNOWN		8
64#define KERB_ERR_PRINCIPAL_NOT_UNIQUE		9
65#define KERB_ERR_NULL_KEY			10
66
67struct krb {
68	u_int8_t pvno;		/* Protocol Version */
69	u_int8_t type;		/* Type+B */
70};
71
72static char tstr[] = " [|kerberos]";
73
74static const struct tok type2str[] = {
75	{ AUTH_MSG_KDC_REQUEST,		"KDC_REQUEST" },
76	{ AUTH_MSG_KDC_REPLY,		"KDC_REPLY" },
77	{ AUTH_MSG_APPL_REQUEST,	"APPL_REQUEST" },
78	{ AUTH_MSG_APPL_REQUEST_MUTUAL,	"APPL_REQUEST_MUTUAL" },
79	{ AUTH_MSG_ERR_REPLY,		"ERR_REPLY" },
80	{ AUTH_MSG_PRIVATE,		"PRIVATE" },
81	{ AUTH_MSG_SAFE,		"SAFE" },
82	{ AUTH_MSG_APPL_ERR,		"APPL_ERR" },
83	{ AUTH_MSG_DIE,			"DIE" },
84	{ 0,				NULL }
85};
86
87static const struct tok kerr2str[] = {
88	{ KERB_ERR_OK,			"OK" },
89	{ KERB_ERR_NAME_EXP,		"NAME_EXP" },
90	{ KERB_ERR_SERVICE_EXP,		"SERVICE_EXP" },
91	{ KERB_ERR_AUTH_EXP,		"AUTH_EXP" },
92	{ KERB_ERR_PKT_VER,		"PKT_VER" },
93	{ KERB_ERR_NAME_MAST_KEY_VER,	"NAME_MAST_KEY_VER" },
94	{ KERB_ERR_SERV_MAST_KEY_VER,	"SERV_MAST_KEY_VER" },
95	{ KERB_ERR_BYTE_ORDER,		"BYTE_ORDER" },
96	{ KERB_ERR_PRINCIPAL_UNKNOWN,	"PRINCIPAL_UNKNOWN" },
97	{ KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" },
98	{ KERB_ERR_NULL_KEY,		"NULL_KEY"},
99	{ 0,				NULL}
100};
101
102static const u_char *
103c_print(register const u_char *s, register const u_char *ep)
104{
105	register u_char c;
106	register int flag;
107
108	flag = 1;
109	while (s < ep) {
110		c = *s++;
111		if (c == '\0') {
112			flag = 0;
113			break;
114		}
115		if (!ND_ISASCII(c)) {
116			c = ND_TOASCII(c);
117			putchar('M');
118			putchar('-');
119		}
120		if (!ND_ISPRINT(c)) {
121			c ^= 0x40;	/* DEL to ?, others to alpha */
122			putchar('^');
123		}
124		putchar(c);
125	}
126	if (flag)
127		return NULL;
128	return (s);
129}
130
131static const u_char *
132krb4_print_hdr(const u_char *cp)
133{
134	cp += 2;
135
136#define PRINT		if ((cp = c_print(cp, snapend)) == NULL) goto trunc
137
138	PRINT;
139	putchar('.');
140	PRINT;
141	putchar('@');
142	PRINT;
143	return (cp);
144
145trunc:
146	fputs(tstr, stdout);
147	return (NULL);
148
149#undef PRINT
150}
151
152static void
153krb4_print(const u_char *cp)
154{
155	register const struct krb *kp;
156	u_char type;
157	u_short len;
158
159#define PRINT		if ((cp = c_print(cp, snapend)) == NULL) goto trunc
160/*  True if struct krb is little endian */
161#define IS_LENDIAN(kp)	(((kp)->type & 0x01) != 0)
162#define KTOHSP(kp, cp)	(IS_LENDIAN(kp) ? EXTRACT_LE_16BITS(cp) : EXTRACT_16BITS(cp))
163
164	kp = (struct krb *)cp;
165
166	if ((&kp->type) >= snapend) {
167		fputs(tstr, stdout);
168		return;
169	}
170
171	type = kp->type & (0xFF << 1);
172
173	printf(" %s %s: ",
174	    IS_LENDIAN(kp) ? "le" : "be", tok2str(type2str, NULL, type));
175
176	switch (type) {
177
178	case AUTH_MSG_KDC_REQUEST:
179		if ((cp = krb4_print_hdr(cp)) == NULL)
180			return;
181		cp += 4;	/* ctime */
182		TCHECK(*cp);
183		printf(" %dmin ", *cp++ * 5);
184		PRINT;
185		putchar('.');
186		PRINT;
187		break;
188
189	case AUTH_MSG_APPL_REQUEST:
190		cp += 2;
191		TCHECK(*cp);
192		printf("v%d ", *cp++);
193		PRINT;
194		TCHECK(*cp);
195		printf(" (%d)", *cp++);
196		TCHECK(*cp);
197		printf(" (%d)", *cp);
198		break;
199
200	case AUTH_MSG_KDC_REPLY:
201		if ((cp = krb4_print_hdr(cp)) == NULL)
202			return;
203		cp += 10;	/* timestamp + n + exp + kvno */
204		TCHECK2(*cp, sizeof(short));
205		len = KTOHSP(kp, cp);
206		printf(" (%d)", len);
207		break;
208
209	case AUTH_MSG_ERR_REPLY:
210		if ((cp = krb4_print_hdr(cp)) == NULL)
211			return;
212		cp += 4; 	  /* timestamp */
213		TCHECK2(*cp, sizeof(short));
214		printf(" %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp)));
215		cp += 4;
216		PRINT;
217		break;
218
219	default:
220		fputs("(unknown)", stdout);
221		break;
222	}
223
224	return;
225trunc:
226	fputs(tstr, stdout);
227}
228
229void
230krb_print(const u_char *dat)
231{
232	register const struct krb *kp;
233
234	kp = (struct krb *)dat;
235
236	if (dat >= snapend) {
237		fputs(tstr, stdout);
238		return;
239	}
240
241	switch (kp->pvno) {
242
243	case 1:
244	case 2:
245	case 3:
246		printf(" v%d", kp->pvno);
247		break;
248
249	case 4:
250		printf(" v%d", kp->pvno);
251		krb4_print((const u_char *)kp);
252		break;
253
254	case 106:
255	case 107:
256		fputs(" v5", stdout);
257		/* Decode ASN.1 here "someday" */
258		break;
259	}
260	return;
261}
262