xref: /openbsd/usr.sbin/tcpdump/print-krb.c (revision 09467b48)
1 /*	$OpenBSD: print-krb.c,v 1.13 2020/01/24 22:46:37 procter Exp $	*/
2 
3 /*
4  * Copyright (c) 1995, 1996, 1997
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  *
23  * Initial contribution from John Hawkinson (jhawk@mit.edu).
24  */
25 
26 #include <sys/time.h>
27 #include <sys/socket.h>
28 
29 #include <netinet/in.h>
30 #include <netinet/ip.h>
31 #include <netinet/ip_var.h>
32 #include <netinet/udp.h>
33 #include <netinet/udp_var.h>
34 
35 #include <ctype.h>
36 #include <errno.h>
37 #include <stdio.h>
38 
39 #include "interface.h"
40 #include "addrtoname.h"
41 
42 const u_char *c_print(const u_char *, const u_char *);
43 const u_char *krb4_print_hdr(const u_char *);
44 void krb4_print(const u_char *);
45 void krb_print(const u_char *, u_int);
46 
47 
48 #define AUTH_MSG_KDC_REQUEST			1<<1
49 #define AUTH_MSG_KDC_REPLY			2<<1
50 #define AUTH_MSG_APPL_REQUEST			3<<1
51 #define AUTH_MSG_APPL_REQUEST_MUTUAL		4<<1
52 #define AUTH_MSG_ERR_REPLY			5<<1
53 #define AUTH_MSG_PRIVATE			6<<1
54 #define AUTH_MSG_SAFE				7<<1
55 #define AUTH_MSG_APPL_ERR			8<<1
56 #define AUTH_MSG_DIE				63<<1
57 
58 #define KERB_ERR_OK				0
59 #define KERB_ERR_NAME_EXP			1
60 #define KERB_ERR_SERVICE_EXP			2
61 #define KERB_ERR_AUTH_EXP			3
62 #define KERB_ERR_PKT_VER			4
63 #define KERB_ERR_NAME_MAST_KEY_VER		5
64 #define KERB_ERR_SERV_MAST_KEY_VER		6
65 #define KERB_ERR_BYTE_ORDER			7
66 #define KERB_ERR_PRINCIPAL_UNKNOWN		8
67 #define KERB_ERR_PRINCIPAL_NOT_UNIQUE		9
68 #define KERB_ERR_NULL_KEY			10
69 
70 struct krb {
71 	u_char pvno;		/* Protocol Version */
72 	u_char type;		/* Type+B */
73 };
74 
75 static char tstr[] = " [|kerberos]";
76 
77 static struct tok type2str[] = {
78 	{ AUTH_MSG_KDC_REQUEST,		"KDC_REQUEST" },
79 	{ AUTH_MSG_KDC_REPLY,		"KDC_REPLY" },
80 	{ AUTH_MSG_APPL_REQUEST,	"APPL_REQUEST" },
81 	{ AUTH_MSG_APPL_REQUEST_MUTUAL,	"APPL_REQUEST_MUTUAL" },
82 	{ AUTH_MSG_ERR_REPLY,		"ERR_REPLY" },
83 	{ AUTH_MSG_PRIVATE,		"PRIVATE" },
84 	{ AUTH_MSG_SAFE,		"SAFE" },
85 	{ AUTH_MSG_APPL_ERR,		"APPL_ERR" },
86 	{ AUTH_MSG_DIE,			"DIE" },
87 	{ 0,				NULL }
88 };
89 
90 static struct tok kerr2str[] = {
91 	{ KERB_ERR_OK,			"OK" },
92 	{ KERB_ERR_NAME_EXP,		"NAME_EXP" },
93 	{ KERB_ERR_SERVICE_EXP,		"SERVICE_EXP" },
94 	{ KERB_ERR_AUTH_EXP,		"AUTH_EXP" },
95 	{ KERB_ERR_PKT_VER,		"PKT_VER" },
96 	{ KERB_ERR_NAME_MAST_KEY_VER,	"NAME_MAST_KEY_VER" },
97 	{ KERB_ERR_SERV_MAST_KEY_VER,	"SERV_MAST_KEY_VER" },
98 	{ KERB_ERR_BYTE_ORDER,		"BYTE_ORDER" },
99 	{ KERB_ERR_PRINCIPAL_UNKNOWN,	"PRINCIPAL_UNKNOWN" },
100 	{ KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" },
101 	{ KERB_ERR_NULL_KEY,		"NULL_KEY"},
102 	{ 0,				NULL}
103 };
104 
105 
106 /* little endian (unaligned) to host byte order */
107 /* XXX need to look at this... */
108 #define vtohlp(x)	    ((( ((char *)(x))[0] )      )  | \
109 			     (( ((char *)(x))[1] ) <<  8)  | \
110 			     (( ((char *)(x))[2] ) << 16)  | \
111 			     (( ((char *)(x))[3] ) << 24))
112 #define vtohsp(x)          ((( ((char *)(x))[0] )      )  | \
113 			     (( ((char *)(x))[1] ) <<  8))
114 /* network (big endian) (unaligned) to host byte order */
115 #define ntohlp(x)	    ((( ((char *)(x))[3] )      )  | \
116 			     (( ((char *)(x))[2] ) <<  8)  | \
117 			     (( ((char *)(x))[1] ) << 16)  | \
118 			     (( ((char *)(x))[0] ) << 24))
119 #define ntohsp(x)          ((( ((char *)(x))[1] )      )  | \
120 			     (( ((char *)(x))[0] ) <<  8))
121 
122 
123 
124 const u_char *
125 c_print(const u_char *s, const u_char *ep)
126 {
127 	u_char c;
128 	int flag;
129 
130 	flag = 1;
131 	while (ep == NULL || s < ep) {
132 		c = *s++;
133 		if (c == '\0') {
134 			flag = 0;
135 			break;
136 		}
137 		if (!isascii(c)) {
138 			c = toascii(c);
139 			putchar('M');
140 			putchar('-');
141 		}
142 		if (!isprint(c)) {
143 			c ^= 0x40;	/* DEL to ?, others to alpha */
144 			putchar('^');
145 		}
146 		putchar(c);
147 	}
148 	if (flag)
149 		return NULL;
150 	return (s);
151 }
152 
153 const u_char *
154 krb4_print_hdr(const u_char *cp)
155 {
156 	cp += 2;
157 
158 #define PRINT		if ((cp = c_print(cp, snapend)) == NULL) goto trunc
159 
160 	TCHECK2(cp, 0);
161 	PRINT;
162 	TCHECK2(cp, 0);
163 	putchar('.'); PRINT;
164 	TCHECK2(cp, 0);
165 	putchar('@'); PRINT;
166 	return(cp);
167 
168 trunc:
169 	printf("%s", tstr);
170 	return (NULL);
171 
172 #undef PRINT
173 }
174 
175 void
176 krb4_print(const u_char *cp)
177 {
178 	const struct krb *kp;
179 	u_char type;
180 	u_short len;
181 
182 #define PRINT		if ((cp = c_print(cp, snapend)) == NULL) goto trunc
183 /*  True if struct krb is little endian */
184 #define IS_LENDIAN(kp)	(((kp)->type & 0x01) != 0)
185 #define KTOHSP(kp, cp)	(IS_LENDIAN(kp) ? vtohsp(cp) : ntohsp(cp))
186 
187 	kp = (struct krb *)cp;
188 
189 	if ((&kp->type) >= snapend) {
190 		printf("%s", tstr);
191 		return;
192 	}
193 
194 	type = kp->type & (0xFF << 1);
195 
196 	printf(" %s %s: ",
197 	    IS_LENDIAN(kp) ? "le" : "be", tok2str(type2str, NULL, type));
198 
199 	switch (type) {
200 
201 	case AUTH_MSG_KDC_REQUEST:
202 		if ((cp = krb4_print_hdr(cp)) == NULL)
203 			return;
204 		cp += 4; 	  /* ctime */
205 		TCHECK2(cp, 0);
206 		printf(" %dmin ", *cp++ * 5);
207 		TCHECK2(cp, 0);
208 		PRINT;
209 		TCHECK2(cp, 0);
210 		putchar('.');  PRINT;
211 		break;
212 
213 	case AUTH_MSG_APPL_REQUEST:
214 		cp += 2;
215 		TCHECK2(cp, 0);
216 		printf("v%d ", *cp++);
217 		TCHECK2(cp, 0);
218 		PRINT;
219 		TCHECK2(cp, 0);
220 		printf(" (%d)", *cp++);
221 		TCHECK2(cp, 0);
222 		printf(" (%d)", *cp);
223 		TCHECK2(cp, 0);
224 		break;
225 
226 	case AUTH_MSG_KDC_REPLY:
227 		if ((cp = krb4_print_hdr(cp)) == NULL)
228 			return;
229 		cp += 10;	/* timestamp + n + exp + kvno */
230 		TCHECK2(cp, 0);
231 		len = KTOHSP(kp, cp);
232 		printf(" (%d)", len);
233 		TCHECK2(cp, 0);
234 		break;
235 
236 	case AUTH_MSG_ERR_REPLY:
237 		if ((cp = krb4_print_hdr(cp)) == NULL)
238 			return;
239 		cp += 4; 	  /* timestamp */
240 		TCHECK2(cp, 0);
241 		printf(" %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp)));
242 		cp += 4;
243 		TCHECK2(cp, 0);
244 		PRINT;
245 		break;
246 
247 	default:
248 		printf("(unknown)");
249 		break;
250 	}
251 
252 	return;
253 trunc:
254 	printf("%s", tstr);
255 }
256 
257 void
258 krb_print(const u_char *dat, u_int length)
259 {
260 	const struct krb *kp;
261 
262 	kp = (struct krb *)dat;
263 
264 	if (dat >= snapend) {
265 		printf("%s", tstr);
266 		return;
267 	}
268 
269 	switch (kp->pvno) {
270 
271 	case 1:
272 	case 2:
273 	case 3:
274 		printf("v%d", kp->pvno);
275 		break;
276 
277 	case 4:
278 		printf("v%d", kp->pvno);
279 		krb4_print((const u_char *)kp);
280 		break;
281 
282 	case 106:
283 	case 107:
284 		printf("v5");
285 		/* Decode ASN.1 here "someday" */
286 		break;
287 	}
288 	return;
289 }
290