xref: /freebsd/crypto/heimdal/kuser/kimpersonate.c (revision 6a068746777241722b2b32c5d0bc443a2a64d80b)
1 /*
2  * Copyright (c) 2000 - 2007 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "kuser_locl.h"
35 #include <parse_units.h>
36 
37 static char *client_principal_str = NULL;
38 static krb5_principal client_principal;
39 static char *server_principal_str = NULL;
40 static krb5_principal server_principal;
41 
42 static char *ccache_str = NULL;
43 
44 static char *ticket_flags_str = NULL;
45 static TicketFlags ticket_flags;
46 static char *keytab_file = NULL;
47 static char *enctype_string = NULL;
48 static int   expiration_time = 3600;
49 static struct getarg_strings client_addresses;
50 static int   version_flag = 0;
51 static int   help_flag = 0;
52 static int   use_krb5 = 1;
53 
54 static const char *enc_type = "des-cbc-md5";
55 
56 /*
57  *
58  */
59 
60 static void
encode_ticket(krb5_context context,EncryptionKey * skey,krb5_enctype etype,int skvno,krb5_creds * cred)61 encode_ticket (krb5_context context,
62 	       EncryptionKey *skey,
63 	       krb5_enctype etype,
64 	       int skvno,
65 	       krb5_creds *cred)
66 {
67     size_t len, size;
68     char *buf;
69     krb5_error_code ret;
70     krb5_crypto crypto;
71     EncryptedData enc_part;
72     EncTicketPart et;
73     Ticket ticket;
74 
75     memset (&enc_part, 0, sizeof(enc_part));
76     memset (&ticket, 0, sizeof(ticket));
77 
78     /*
79      * Set up `enc_part'
80      */
81 
82     et.flags = cred->flags.b;
83     et.key = cred->session;
84     et.crealm = cred->client->realm;
85     copy_PrincipalName(&cred->client->name, &et.cname);
86     {
87 	krb5_data empty_string;
88 
89 	krb5_data_zero(&empty_string);
90 	et.transited.tr_type = DOMAIN_X500_COMPRESS;
91 	et.transited.contents = empty_string;
92     }
93     et.authtime = cred->times.authtime;
94     et.starttime = NULL;
95     et.endtime = cred->times.endtime;
96     et.renew_till = NULL;
97     et.caddr = &cred->addresses;
98     et.authorization_data = NULL; /* XXX allow random authorization_data */
99 
100     /*
101      * Encrypt `enc_part' of ticket with service key
102      */
103 
104     ASN1_MALLOC_ENCODE(EncTicketPart, buf, len, &et, &size, ret);
105     if (ret)
106 	krb5_err(context, 1, ret, "EncTicketPart");
107 
108     ret = krb5_crypto_init(context, skey, etype, &crypto);
109     if (ret)
110 	krb5_err(context, 1, ret, "krb5_crypto_init");
111     ret = krb5_encrypt_EncryptedData (context,
112 				      crypto,
113 				      KRB5_KU_TICKET,
114 				      buf,
115 				      len,
116 				      skvno,
117 				      &ticket.enc_part);
118     if (ret)
119 	krb5_err(context, 1, ret, "krb5_encrypt_EncryptedData");
120 
121     free(buf);
122     krb5_crypto_destroy(context, crypto);
123 
124     /*
125      * Encode ticket
126      */
127 
128     ticket.tkt_vno = 5;
129     ticket.realm = cred->server->realm;
130     copy_PrincipalName(&cred->server->name, &ticket.sname);
131 
132     ASN1_MALLOC_ENCODE(Ticket, buf, len, &ticket, &size, ret);
133     if(ret)
134 	krb5_err (context, 1, ret, "encode_Ticket");
135 
136     krb5_data_copy(&cred->ticket, buf, len);
137     free(buf);
138 }
139 
140 /*
141  *
142  */
143 
144 static int
create_krb5_tickets(krb5_context context,krb5_keytab kt)145 create_krb5_tickets (krb5_context context, krb5_keytab kt)
146 {
147     krb5_error_code ret;
148     krb5_keytab_entry entry;
149     krb5_creds cred;
150     krb5_enctype etype;
151     krb5_ccache ccache;
152 
153     memset (&cred, 0, sizeof(cred));
154 
155     ret = krb5_string_to_enctype (context, enc_type, &etype);
156     if (ret)
157 	krb5_err (context, 1, ret, "krb5_string_to_enctype");
158     ret = krb5_kt_get_entry (context, kt, server_principal,
159 			     0, etype, &entry);
160     if (ret)
161 	krb5_err (context, 1, ret, "krb5_kt_get_entry");
162 
163     /*
164      * setup cred
165      */
166 
167 
168     ret = krb5_copy_principal (context, client_principal, &cred.client);
169     if (ret)
170 	krb5_err (context, 1, ret, "krb5_copy_principal");
171     ret = krb5_copy_principal (context, server_principal, &cred.server);
172     if (ret)
173 	krb5_err (context, 1, ret, "krb5_copy_principal");
174     krb5_generate_random_keyblock(context, etype, &cred.session);
175 
176     cred.times.authtime = time(NULL);
177     cred.times.starttime = time(NULL);
178     cred.times.endtime = time(NULL) + expiration_time;
179     cred.times.renew_till = 0;
180     krb5_data_zero(&cred.second_ticket);
181 
182     ret = krb5_get_all_client_addrs (context, &cred.addresses);
183     if (ret)
184 	krb5_err (context, 1, ret, "krb5_get_all_client_addrs");
185     cred.flags.b = ticket_flags;
186 
187 
188     /*
189      * Encode encrypted part of ticket
190      */
191 
192     encode_ticket (context, &entry.keyblock, etype, entry.vno, &cred);
193 
194     /*
195      * Write to cc
196      */
197 
198     if (ccache_str) {
199 	ret = krb5_cc_resolve(context, ccache_str, &ccache);
200 	if (ret)
201 	    krb5_err (context, 1, ret, "krb5_cc_resolve");
202     } else {
203 	ret = krb5_cc_default (context, &ccache);
204 	if (ret)
205 	    krb5_err (context, 1, ret, "krb5_cc_default");
206     }
207 
208     ret = krb5_cc_initialize (context, ccache, cred.client);
209     if (ret)
210 	krb5_err (context, 1, ret, "krb5_cc_initialize");
211 
212     ret = krb5_cc_store_cred (context, ccache, &cred);
213     if (ret)
214 	krb5_err (context, 1, ret, "krb5_cc_store_cred");
215 
216     krb5_free_cred_contents (context, &cred);
217     krb5_cc_close (context, ccache);
218 
219     return 0;
220 }
221 
222 /*
223  *
224  */
225 
226 static void
setup_env(krb5_context context,krb5_keytab * kt)227 setup_env (krb5_context context, krb5_keytab *kt)
228 {
229     krb5_error_code ret;
230 
231     if (keytab_file)
232 	ret = krb5_kt_resolve (context, keytab_file, kt);
233     else
234 	ret = krb5_kt_default (context, kt);
235     if (ret)
236 	krb5_err (context, 1, ret, "resolving keytab");
237 
238     if (client_principal_str == NULL)
239 	krb5_errx (context, 1, "missing client principal");
240     ret = krb5_parse_name (context, client_principal_str, &client_principal);
241     if (ret)
242 	krb5_err (context, 1, ret, "resolvning client name");
243 
244     if (server_principal_str == NULL)
245 	krb5_errx (context, 1, "missing server principal");
246     ret = krb5_parse_name (context, server_principal_str, &server_principal);
247     if (ret)
248 	krb5_err (context, 1, ret, "resolvning client name");
249 
250     if (ticket_flags_str) {
251 	int ticket_flags_int;
252 
253 	ticket_flags_int = parse_flags(ticket_flags_str,
254 				       asn1_TicketFlags_units(), 0);
255 	if (ticket_flags_int <= 0) {
256 	    krb5_warnx (context, "bad ticket flags: `%s'", ticket_flags_str);
257 	    print_flags_table (asn1_TicketFlags_units(), stderr);
258 	    exit (1);
259 	}
260 	if (ticket_flags_int)
261 	    ticket_flags = int2TicketFlags (ticket_flags_int);
262     }
263 }
264 
265 /*
266  *
267  */
268 
269 struct getargs args[] = {
270     { "ccache", 0, arg_string, &ccache_str,
271       "name of kerberos 5 credential cache", "cache-name"},
272     { "server", 's', arg_string, &server_principal_str,
273       "name of server principal", NULL },
274     { "client", 'c', arg_string, &client_principal_str,
275       "name of client principal", NULL },
276     { "keytab", 'k', arg_string, &keytab_file,
277       "name of keytab file", NULL },
278     { "krb5", '5', arg_flag,	 &use_krb5,
279       "create a kerberos 5 ticket", NULL },
280     { "expire-time", 'e', arg_integer, &expiration_time,
281       "lifetime of ticket in seconds", NULL },
282     { "client-addresses", 'a', arg_strings, &client_addresses,
283       "addresses of client", NULL },
284     { "enc-type", 't', arg_string, 	&enctype_string,
285       "encryption type", NULL },
286     { "ticket-flags", 'f', arg_string,   &ticket_flags_str,
287       "ticket flags for krb5 ticket", NULL },
288     { "version", 0,  arg_flag,		&version_flag,	"Print version",
289       NULL },
290     { "help",	 0,  arg_flag,		&help_flag,	NULL,
291       NULL }
292 };
293 
294 static void
usage(int ret)295 usage (int ret)
296 {
297     arg_printusage (args,
298 		    sizeof(args) / sizeof(args[0]),
299 		    NULL,
300 		    "");
301     exit (ret);
302 }
303 
304 int
main(int argc,char ** argv)305 main (int argc, char **argv)
306 {
307     int optidx = 0;
308     krb5_error_code ret;
309     krb5_context context;
310     krb5_keytab kt;
311 
312     setprogname (argv[0]);
313 
314     ret = krb5_init_context (&context);
315     if (ret)
316 	errx(1, "krb5_init_context failed: %u", ret);
317 
318     if (getarg(args, sizeof(args) / sizeof(args[0]), argc, argv, &optidx))
319 	usage(1);
320 
321     if (help_flag)
322 	usage(0);
323 
324     if (version_flag) {
325 	print_version(NULL);
326 	return 0;
327     }
328 
329     if (enctype_string)
330 	enc_type = enctype_string;
331 
332     setup_env(context, &kt);
333 
334     if (use_krb5)
335 	create_krb5_tickets(context, kt);
336 
337     krb5_kt_close(context, kt);
338 
339     return 0;
340 }
341