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/* \summary: Kerberos printer */
25
26#ifdef HAVE_CONFIG_H
27#include "config.h"
28#endif
29
30#include <netdissect-stdinc.h>
31
32#include "netdissect.h"
33#include "extract.h"
34
35static const char tstr[] = " [|kerberos]";
36
37static const u_char *c_print(netdissect_options *, register const u_char *, register const u_char *);
38static const u_char *krb4_print_hdr(netdissect_options *, const u_char *);
39static void krb4_print(netdissect_options *, const u_char *);
40
41#define AUTH_MSG_KDC_REQUEST			1<<1
42#define AUTH_MSG_KDC_REPLY			2<<1
43#define AUTH_MSG_APPL_REQUEST			3<<1
44#define AUTH_MSG_APPL_REQUEST_MUTUAL		4<<1
45#define AUTH_MSG_ERR_REPLY			5<<1
46#define AUTH_MSG_PRIVATE			6<<1
47#define AUTH_MSG_SAFE				7<<1
48#define AUTH_MSG_APPL_ERR			8<<1
49#define AUTH_MSG_DIE				63<<1
50
51#define KERB_ERR_OK				0
52#define KERB_ERR_NAME_EXP			1
53#define KERB_ERR_SERVICE_EXP			2
54#define KERB_ERR_AUTH_EXP			3
55#define KERB_ERR_PKT_VER			4
56#define KERB_ERR_NAME_MAST_KEY_VER		5
57#define KERB_ERR_SERV_MAST_KEY_VER		6
58#define KERB_ERR_BYTE_ORDER			7
59#define KERB_ERR_PRINCIPAL_UNKNOWN		8
60#define KERB_ERR_PRINCIPAL_NOT_UNIQUE		9
61#define KERB_ERR_NULL_KEY			10
62
63struct krb {
64	uint8_t pvno;		/* Protocol Version */
65	uint8_t type;		/* Type+B */
66};
67
68static const struct tok type2str[] = {
69	{ AUTH_MSG_KDC_REQUEST,		"KDC_REQUEST" },
70	{ AUTH_MSG_KDC_REPLY,		"KDC_REPLY" },
71	{ AUTH_MSG_APPL_REQUEST,	"APPL_REQUEST" },
72	{ AUTH_MSG_APPL_REQUEST_MUTUAL,	"APPL_REQUEST_MUTUAL" },
73	{ AUTH_MSG_ERR_REPLY,		"ERR_REPLY" },
74	{ AUTH_MSG_PRIVATE,		"PRIVATE" },
75	{ AUTH_MSG_SAFE,		"SAFE" },
76	{ AUTH_MSG_APPL_ERR,		"APPL_ERR" },
77	{ AUTH_MSG_DIE,			"DIE" },
78	{ 0,				NULL }
79};
80
81static const struct tok kerr2str[] = {
82	{ KERB_ERR_OK,			"OK" },
83	{ KERB_ERR_NAME_EXP,		"NAME_EXP" },
84	{ KERB_ERR_SERVICE_EXP,		"SERVICE_EXP" },
85	{ KERB_ERR_AUTH_EXP,		"AUTH_EXP" },
86	{ KERB_ERR_PKT_VER,		"PKT_VER" },
87	{ KERB_ERR_NAME_MAST_KEY_VER,	"NAME_MAST_KEY_VER" },
88	{ KERB_ERR_SERV_MAST_KEY_VER,	"SERV_MAST_KEY_VER" },
89	{ KERB_ERR_BYTE_ORDER,		"BYTE_ORDER" },
90	{ KERB_ERR_PRINCIPAL_UNKNOWN,	"PRINCIPAL_UNKNOWN" },
91	{ KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" },
92	{ KERB_ERR_NULL_KEY,		"NULL_KEY"},
93	{ 0,				NULL}
94};
95
96static const u_char *
97c_print(netdissect_options *ndo,
98        register const u_char *s, register const u_char *ep)
99{
100	register u_char c;
101	register int flag;
102
103	flag = 1;
104	while (s < ep) {
105		c = *s++;
106		if (c == '\0') {
107			flag = 0;
108			break;
109		}
110		if (!ND_ISASCII(c)) {
111			c = ND_TOASCII(c);
112			ND_PRINT((ndo, "M-"));
113		}
114		if (!ND_ISPRINT(c)) {
115			c ^= 0x40;	/* DEL to ?, others to alpha */
116			ND_PRINT((ndo, "^"));
117		}
118		ND_PRINT((ndo, "%c", c));
119	}
120	if (flag)
121		return NULL;
122	return (s);
123}
124
125static const u_char *
126krb4_print_hdr(netdissect_options *ndo,
127               const u_char *cp)
128{
129	cp += 2;
130
131#define PRINT		if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
132
133	PRINT;
134	ND_PRINT((ndo, "."));
135	PRINT;
136	ND_PRINT((ndo, "@"));
137	PRINT;
138	return (cp);
139
140trunc:
141	ND_PRINT((ndo, "%s", tstr));
142	return (NULL);
143
144#undef PRINT
145}
146
147static void
148krb4_print(netdissect_options *ndo,
149           const u_char *cp)
150{
151	register const struct krb *kp;
152	u_char type;
153	u_short len;
154
155#define PRINT		if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
156/*  True if struct krb is little endian */
157#define IS_LENDIAN(kp)	(((kp)->type & 0x01) != 0)
158#define KTOHSP(kp, cp)	(IS_LENDIAN(kp) ? EXTRACT_LE_16BITS(cp) : EXTRACT_16BITS(cp))
159
160	kp = (const struct krb *)cp;
161
162	if ((&kp->type) >= ndo->ndo_snapend) {
163		ND_PRINT((ndo, "%s", tstr));
164		return;
165	}
166
167	type = kp->type & (0xFF << 1);
168
169	ND_PRINT((ndo, " %s %s: ",
170	    IS_LENDIAN(kp) ? "le" : "be", tok2str(type2str, NULL, type)));
171
172	switch (type) {
173
174	case AUTH_MSG_KDC_REQUEST:
175		if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
176			return;
177		cp += 4;	/* ctime */
178		ND_TCHECK(*cp);
179		ND_PRINT((ndo, " %dmin ", *cp++ * 5));
180		PRINT;
181		ND_PRINT((ndo, "."));
182		PRINT;
183		break;
184
185	case AUTH_MSG_APPL_REQUEST:
186		cp += 2;
187		ND_TCHECK(*cp);
188		ND_PRINT((ndo, "v%d ", *cp++));
189		PRINT;
190		ND_TCHECK(*cp);
191		ND_PRINT((ndo, " (%d)", *cp++));
192		ND_TCHECK(*cp);
193		ND_PRINT((ndo, " (%d)", *cp));
194		break;
195
196	case AUTH_MSG_KDC_REPLY:
197		if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
198			return;
199		cp += 10;	/* timestamp + n + exp + kvno */
200		ND_TCHECK2(*cp, sizeof(short));
201		len = KTOHSP(kp, cp);
202		ND_PRINT((ndo, " (%d)", len));
203		break;
204
205	case AUTH_MSG_ERR_REPLY:
206		if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
207			return;
208		cp += 4; 	  /* timestamp */
209		ND_TCHECK2(*cp, sizeof(short));
210		ND_PRINT((ndo, " %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp))));
211		cp += 4;
212		PRINT;
213		break;
214
215	default:
216		ND_PRINT((ndo, "(unknown)"));
217		break;
218	}
219
220	return;
221trunc:
222	ND_PRINT((ndo, "%s", tstr));
223}
224
225void
226krb_print(netdissect_options *ndo,
227          const u_char *dat)
228{
229	register const struct krb *kp;
230
231	kp = (const struct krb *)dat;
232
233	if (dat >= ndo->ndo_snapend) {
234		ND_PRINT((ndo, "%s", tstr));
235		return;
236	}
237
238	switch (kp->pvno) {
239
240	case 1:
241	case 2:
242	case 3:
243		ND_PRINT((ndo, " v%d", kp->pvno));
244		break;
245
246	case 4:
247		ND_PRINT((ndo, " v%d", kp->pvno));
248		krb4_print(ndo, (const u_char *)kp);
249		break;
250
251	case 106:
252	case 107:
253		ND_PRINT((ndo, " v5"));
254		/* Decode ASN.1 here "someday" */
255		break;
256	}
257	return;
258}
259