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 #include <sys/cdefs.h>
25 #ifndef lint
26 __RCSID("$NetBSD: print-krb.c,v 1.5 2014/11/20 03:05:03 christos Exp $");
27 #endif
28
29 #define NETDISSECT_REWORKED
30 #ifdef HAVE_CONFIG_H
31 #include "config.h"
32 #endif
33
34 #include <tcpdump-stdinc.h>
35
36 #include "interface.h"
37 #include "extract.h"
38
39 static const char tstr[] = " [|kerberos]";
40
41 static const u_char *c_print(netdissect_options *, register const u_char *, register const u_char *);
42 static const u_char *krb4_print_hdr(netdissect_options *, const u_char *);
43 static void krb4_print(netdissect_options *, 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
67 struct krb {
68 uint8_t pvno; /* Protocol Version */
69 uint8_t type; /* Type+B */
70 };
71
72 static const struct tok type2str[] = {
73 { AUTH_MSG_KDC_REQUEST, "KDC_REQUEST" },
74 { AUTH_MSG_KDC_REPLY, "KDC_REPLY" },
75 { AUTH_MSG_APPL_REQUEST, "APPL_REQUEST" },
76 { AUTH_MSG_APPL_REQUEST_MUTUAL, "APPL_REQUEST_MUTUAL" },
77 { AUTH_MSG_ERR_REPLY, "ERR_REPLY" },
78 { AUTH_MSG_PRIVATE, "PRIVATE" },
79 { AUTH_MSG_SAFE, "SAFE" },
80 { AUTH_MSG_APPL_ERR, "APPL_ERR" },
81 { AUTH_MSG_DIE, "DIE" },
82 { 0, NULL }
83 };
84
85 static const struct tok kerr2str[] = {
86 { KERB_ERR_OK, "OK" },
87 { KERB_ERR_NAME_EXP, "NAME_EXP" },
88 { KERB_ERR_SERVICE_EXP, "SERVICE_EXP" },
89 { KERB_ERR_AUTH_EXP, "AUTH_EXP" },
90 { KERB_ERR_PKT_VER, "PKT_VER" },
91 { KERB_ERR_NAME_MAST_KEY_VER, "NAME_MAST_KEY_VER" },
92 { KERB_ERR_SERV_MAST_KEY_VER, "SERV_MAST_KEY_VER" },
93 { KERB_ERR_BYTE_ORDER, "BYTE_ORDER" },
94 { KERB_ERR_PRINCIPAL_UNKNOWN, "PRINCIPAL_UNKNOWN" },
95 { KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" },
96 { KERB_ERR_NULL_KEY, "NULL_KEY"},
97 { 0, NULL}
98 };
99
100 static const u_char *
c_print(netdissect_options * ndo,register const u_char * s,register const u_char * ep)101 c_print(netdissect_options *ndo,
102 register const u_char *s, register const u_char *ep)
103 {
104 register u_char c;
105 register int flag;
106
107 flag = 1;
108 while (s < ep) {
109 c = *s++;
110 if (c == '\0') {
111 flag = 0;
112 break;
113 }
114 if (!ND_ISASCII(c)) {
115 c = ND_TOASCII(c);
116 ND_PRINT((ndo, "M-"));
117 }
118 if (!ND_ISPRINT(c)) {
119 c ^= 0x40; /* DEL to ?, others to alpha */
120 ND_PRINT((ndo, "^"));
121 }
122 ND_PRINT((ndo, "%c", c));
123 }
124 if (flag)
125 return NULL;
126 return (s);
127 }
128
129 static const u_char *
krb4_print_hdr(netdissect_options * ndo,const u_char * cp)130 krb4_print_hdr(netdissect_options *ndo,
131 const u_char *cp)
132 {
133 cp += 2;
134
135 #define PRINT if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
136
137 PRINT;
138 ND_PRINT((ndo, "."));
139 PRINT;
140 ND_PRINT((ndo, "@"));
141 PRINT;
142 return (cp);
143
144 trunc:
145 ND_PRINT((ndo, "%s", tstr));
146 return (NULL);
147
148 #undef PRINT
149 }
150
151 static void
krb4_print(netdissect_options * ndo,const u_char * cp)152 krb4_print(netdissect_options *ndo,
153 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(ndo, cp, ndo->ndo_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) >= ndo->ndo_snapend) {
167 ND_PRINT((ndo, "%s", tstr));
168 return;
169 }
170
171 type = kp->type & (0xFF << 1);
172
173 ND_PRINT((ndo, " %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(ndo, cp)) == NULL)
180 return;
181 cp += 4; /* ctime */
182 ND_TCHECK(*cp);
183 ND_PRINT((ndo, " %dmin ", *cp++ * 5));
184 PRINT;
185 ND_PRINT((ndo, "."));
186 PRINT;
187 break;
188
189 case AUTH_MSG_APPL_REQUEST:
190 cp += 2;
191 ND_TCHECK(*cp);
192 ND_PRINT((ndo, "v%d ", *cp++));
193 PRINT;
194 ND_TCHECK(*cp);
195 ND_PRINT((ndo, " (%d)", *cp++));
196 ND_TCHECK(*cp);
197 ND_PRINT((ndo, " (%d)", *cp));
198 break;
199
200 case AUTH_MSG_KDC_REPLY:
201 if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
202 return;
203 cp += 10; /* timestamp + n + exp + kvno */
204 ND_TCHECK2(*cp, sizeof(short));
205 len = KTOHSP(kp, cp);
206 ND_PRINT((ndo, " (%d)", len));
207 break;
208
209 case AUTH_MSG_ERR_REPLY:
210 if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
211 return;
212 cp += 4; /* timestamp */
213 ND_TCHECK2(*cp, sizeof(short));
214 ND_PRINT((ndo, " %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp))));
215 cp += 4;
216 PRINT;
217 break;
218
219 default:
220 ND_PRINT((ndo, "(unknown)"));
221 break;
222 }
223
224 return;
225 trunc:
226 ND_PRINT((ndo, "%s", tstr));
227 }
228
229 void
krb_print(netdissect_options * ndo,const u_char * dat)230 krb_print(netdissect_options *ndo,
231 const u_char *dat)
232 {
233 register const struct krb *kp;
234
235 kp = (struct krb *)dat;
236
237 if (dat >= ndo->ndo_snapend) {
238 ND_PRINT((ndo, "%s", tstr));
239 return;
240 }
241
242 switch (kp->pvno) {
243
244 case 1:
245 case 2:
246 case 3:
247 ND_PRINT((ndo, " v%d", kp->pvno));
248 break;
249
250 case 4:
251 ND_PRINT((ndo, " v%d", kp->pvno));
252 krb4_print(ndo, (const u_char *)kp);
253 break;
254
255 case 106:
256 case 107:
257 ND_PRINT((ndo, " v5"));
258 /* Decode ASN.1 here "someday" */
259 break;
260 }
261 return;
262 }
263