xref: /freebsd/contrib/tcpdump/print-krb.c (revision 0a36787e4c1fa0cf77dcf83be0867178476e372b)
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 
35 static const char tstr[] = " [|kerberos]";
36 
37 static const u_char *c_print(netdissect_options *, register const u_char *, register const u_char *);
38 static const u_char *krb4_print_hdr(netdissect_options *, const u_char *);
39 static 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 
63 struct krb {
64 	uint8_t pvno;		/* Protocol Version */
65 	uint8_t type;		/* Type+B */
66 };
67 
68 static 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 
81 static 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 
96 static const u_char *
97 c_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 
125 static const u_char *
126 krb4_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 
140 trunc:
141 	ND_PRINT((ndo, "%s", tstr));
142 	return (NULL);
143 
144 #undef PRINT
145 }
146 
147 static void
148 krb4_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;
221 trunc:
222 	ND_PRINT((ndo, "%s", tstr));
223 }
224 
225 void
226 krb_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