/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- add_addrs
- krb5_fwd_tgt_creds
- krb5_get_forwarded_creds
1 /*
2 * Copyright (c) 1997 - 2004 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 <krb5_locl.h>
35
36 RCSID("$Id$");
37
38 static krb5_error_code
39 add_addrs(krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
40 krb5_addresses *addr,
41 struct addrinfo *ai)
42 {
43 krb5_error_code ret;
44 unsigned n, i;
45 void *tmp;
46 struct addrinfo *a;
47
48 n = 0;
49 for (a = ai; a != NULL; a = a->ai_next)
50 ++n;
51
52 tmp = realloc(addr->val, (addr->len + n) * sizeof(*addr->val));
53 if (tmp == NULL && (addr->len + n) != 0) {
54 ret = ENOMEM;
55 krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
56 goto fail;
57 }
58 addr->val = tmp;
59 for (i = addr->len; i < (addr->len + n); ++i) {
60 addr->val[i].addr_type = 0;
61 krb5_data_zero(&addr->val[i].address);
62 }
63 i = addr->len;
64 for (a = ai; a != NULL; a = a->ai_next) {
65 krb5_address ad;
66
67 ret = krb5_sockaddr2address (context, a->ai_addr, &ad);
68 if (ret == 0) {
69 if (krb5_address_search(context, &ad, addr))
70 krb5_free_address(context, &ad);
71 else
72 addr->val[i++] = ad;
73 }
74 else if (ret == KRB5_PROG_ATYPE_NOSUPP)
75 krb5_clear_error_message (context);
76 else
77 goto fail;
78 addr->len = i;
79 }
80 return 0;
81 fail:
82 krb5_free_addresses (context, addr);
83 return ret;
84 }
85
86 /**
87 * Forward credentials for client to host hostname , making them
88 * forwardable if forwardable, and returning the blob of data to sent
89 * in out_data. If hostname == NULL, pick it from server.
90 *
91 * @param context A kerberos 5 context.
92 * @param auth_context the auth context with the key to encrypt the out_data.
93 * @param hostname the host to forward the tickets too.
94 * @param client the client to delegate from.
95 * @param server the server to delegate the credential too.
96 * @param ccache credential cache to use.
97 * @param forwardable make the forwarded ticket forwabledable.
98 * @param out_data the resulting credential.
99 *
100 * @return Return an error code or 0.
101 *
102 * @ingroup krb5_credential
103 */
104
105 krb5_error_code KRB5_LIB_FUNCTION
106 krb5_fwd_tgt_creds (krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
107 krb5_auth_context auth_context,
108 const char *hostname,
109 krb5_principal client,
110 krb5_principal server,
111 krb5_ccache ccache,
112 int forwardable,
113 krb5_data *out_data)
114 {
115 krb5_flags flags = 0;
116 krb5_creds creds;
117 krb5_error_code ret;
118 krb5_const_realm client_realm;
119
120 flags |= KDC_OPT_FORWARDED;
121
122 if (forwardable)
123 flags |= KDC_OPT_FORWARDABLE;
124
125 if (hostname == NULL &&
126 krb5_principal_get_type(context, server) == KRB5_NT_SRV_HST) {
127 const char *inst = krb5_principal_get_comp_string(context, server, 0);
128 const char *host = krb5_principal_get_comp_string(context, server, 1);
129
130 if (inst != NULL &&
131 strcmp(inst, "host") == 0 &&
132 host != NULL &&
133 krb5_principal_get_comp_string(context, server, 2) == NULL)
134 hostname = host;
135 }
136
137 client_realm = krb5_principal_get_realm(context, client);
138
139 memset (&creds, 0, sizeof(creds));
140 creds.client = client;
141
142 ret = krb5_build_principal(context,
143 &creds.server,
144 strlen(client_realm),
145 client_realm,
146 KRB5_TGS_NAME,
147 client_realm,
148 NULL);
149 if (ret)
150 return ret;
151
152 ret = krb5_get_forwarded_creds (context,
153 auth_context,
154 ccache,
155 flags,
156 hostname,
157 &creds,
158 out_data);
159 return ret;
160 }
161
162 /**
163 * Gets tickets forwarded to hostname. If the tickets that are
164 * forwarded are address-less, the forwarded tickets will also be
165 * address-less.
166 *
167 * If the ticket have any address, hostname will be used for figure
168 * out the address to forward the ticket too. This since this might
169 * use DNS, its insecure and also doesn't represent configured all
170 * addresses of the host. For example, the host might have two
171 * adresses, one IPv4 and one IPv6 address where the later is not
172 * published in DNS. This IPv6 address might be used communications
173 * and thus the resulting ticket useless.
174 *
175 * @param context A kerberos 5 context.
176 * @param auth_context the auth context with the key to encrypt the out_data.
177 * @param ccache credential cache to use
178 * @param flags the flags to control the resulting ticket flags
179 * @param hostname the host to forward the tickets too.
180 * @param in_creds the in client and server ticket names. The client
181 * and server components forwarded to the remote host.
182 * @param out_data the resulting credential.
183 *
184 * @return Return an error code or 0.
185 *
186 * @ingroup krb5_credential
187 */
188
189 krb5_error_code KRB5_LIB_FUNCTION
190 krb5_get_forwarded_creds (krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
191 krb5_auth_context auth_context,
192 krb5_ccache ccache,
193 krb5_flags flags,
194 const char *hostname,
195 krb5_creds *in_creds,
196 krb5_data *out_data)
197 {
198 krb5_error_code ret;
199 krb5_creds *out_creds;
200 krb5_addresses addrs, *paddrs;
201 KRB_CRED cred;
202 KrbCredInfo *krb_cred_info;
203 EncKrbCredPart enc_krb_cred_part;
204 size_t len;
205 unsigned char *buf;
206 size_t buf_size;
207 krb5_kdc_flags kdc_flags;
208 krb5_crypto crypto;
209 struct addrinfo *ai;
210 krb5_creds *ticket;
211
212 paddrs = NULL;
213 addrs.len = 0;
214 addrs.val = NULL;
215
216 ret = krb5_get_credentials(context, 0, ccache, in_creds, &ticket);
217 if(ret == 0) {
218 if (ticket->addresses.len)
219 paddrs = &addrs;
220 krb5_free_creds (context, ticket);
221 } else {
222 krb5_boolean noaddr;
223 krb5_appdefault_boolean(context, NULL,
224 krb5_principal_get_realm(context,
225 in_creds->client),
226 "no-addresses", KRB5_ADDRESSLESS_DEFAULT,
227 &noaddr);
228 if (!noaddr)
229 paddrs = &addrs;
230 }
231
232 /*
233 * If tickets have addresses, get the address of the remote host.
234 */
235
236 if (paddrs != NULL) {
237
238 ret = getaddrinfo (hostname, NULL, NULL, &ai);
239 if (ret) {
240 krb5_error_code ret2 = krb5_eai_to_heim_errno(ret, errno);
241 krb5_set_error_message(context, ret2,
242 N_("resolving host %s failed: %s",
243 "hostname, error"),
244 hostname, gai_strerror(ret));
245 return ret2;
246 }
247
248 ret = add_addrs (context, &addrs, ai);
249 freeaddrinfo (ai);
250 if (ret)
251 return ret;
252 }
253
254 kdc_flags.b = int2KDCOptions(flags);
255
256 ret = krb5_get_kdc_cred (context,
257 ccache,
258 kdc_flags,
259 paddrs,
260 NULL,
261 in_creds,
262 &out_creds);
263 krb5_free_addresses (context, &addrs);
264 if (ret)
265 return ret;
266
267 memset (&cred, 0, sizeof(cred));
268 cred.pvno = 5;
269 cred.msg_type = krb_cred;
270 ALLOC_SEQ(&cred.tickets, 1);
271 if (cred.tickets.val == NULL) {
272 ret = ENOMEM;
273 krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
274 goto out2;
275 }
276 ret = decode_Ticket(out_creds->ticket.data,
277 out_creds->ticket.length,
278 cred.tickets.val, &len);
279 if (ret)
280 goto out3;
281
282 memset (&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part));
283 ALLOC_SEQ(&enc_krb_cred_part.ticket_info, 1);
284 if (enc_krb_cred_part.ticket_info.val == NULL) {
285 ret = ENOMEM;
286 krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
287 goto out4;
288 }
289
290 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
291 krb5_timestamp sec;
292 int32_t usec;
293
294 krb5_us_timeofday (context, &sec, &usec);
295
296 ALLOC(enc_krb_cred_part.timestamp, 1);
297 if (enc_krb_cred_part.timestamp == NULL) {
298 ret = ENOMEM;
299 krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
300 goto out4;
301 }
302 *enc_krb_cred_part.timestamp = sec;
303 ALLOC(enc_krb_cred_part.usec, 1);
304 if (enc_krb_cred_part.usec == NULL) {
305 ret = ENOMEM;
306 krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
307 goto out4;
308 }
309 *enc_krb_cred_part.usec = usec;
310 } else {
311 enc_krb_cred_part.timestamp = NULL;
312 enc_krb_cred_part.usec = NULL;
313 }
314
315 if (auth_context->local_address && auth_context->local_port && paddrs) {
316
317 ret = krb5_make_addrport (context,
318 &enc_krb_cred_part.s_address,
319 auth_context->local_address,
320 auth_context->local_port);
321 if (ret)
322 goto out4;
323 }
324
325 if (auth_context->remote_address) {
326 if (auth_context->remote_port) {
327 krb5_boolean noaddr;
328 krb5_const_realm srealm;
329
330 srealm = krb5_principal_get_realm(context, out_creds->server);
331 /* Is this correct, and should we use the paddrs == NULL
332 trick here as well? Having an address-less ticket may
333 indicate that we don't know our own global address, but
334 it does not necessary mean that we don't know the
335 server's. */
336 krb5_appdefault_boolean(context, NULL, srealm, "no-addresses",
337 FALSE, &noaddr);
338 if (!noaddr) {
339 ret = krb5_make_addrport (context,
340 &enc_krb_cred_part.r_address,
341 auth_context->remote_address,
342 auth_context->remote_port);
343 if (ret)
344 goto out4;
345 }
346 } else {
347 ALLOC(enc_krb_cred_part.r_address, 1);
348 if (enc_krb_cred_part.r_address == NULL) {
349 ret = ENOMEM;
350 krb5_set_error_message(context, ret,
351 N_("malloc: out of memory", ""));
352 goto out4;
353 }
354
355 ret = krb5_copy_address (context, auth_context->remote_address,
356 enc_krb_cred_part.r_address);
357 if (ret)
358 goto out4;
359 }
360 }
361
362 /* fill ticket_info.val[0] */
363
364 enc_krb_cred_part.ticket_info.len = 1;
365
366 krb_cred_info = enc_krb_cred_part.ticket_info.val;
367
368 copy_EncryptionKey (&out_creds->session, &krb_cred_info->key);
369 ALLOC(krb_cred_info->prealm, 1);
370 copy_Realm (&out_creds->client->realm, krb_cred_info->prealm);
371 ALLOC(krb_cred_info->pname, 1);
372 copy_PrincipalName(&out_creds->client->name, krb_cred_info->pname);
373 ALLOC(krb_cred_info->flags, 1);
374 *krb_cred_info->flags = out_creds->flags.b;
375 ALLOC(krb_cred_info->authtime, 1);
376 *krb_cred_info->authtime = out_creds->times.authtime;
377 ALLOC(krb_cred_info->starttime, 1);
378 *krb_cred_info->starttime = out_creds->times.starttime;
379 ALLOC(krb_cred_info->endtime, 1);
380 *krb_cred_info->endtime = out_creds->times.endtime;
381 ALLOC(krb_cred_info->renew_till, 1);
382 *krb_cred_info->renew_till = out_creds->times.renew_till;
383 ALLOC(krb_cred_info->srealm, 1);
384 copy_Realm (&out_creds->server->realm, krb_cred_info->srealm);
385 ALLOC(krb_cred_info->sname, 1);
386 copy_PrincipalName (&out_creds->server->name, krb_cred_info->sname);
387 ALLOC(krb_cred_info->caddr, 1);
388 copy_HostAddresses (&out_creds->addresses, krb_cred_info->caddr);
389
390 krb5_free_creds (context, out_creds);
391
392 /* encode EncKrbCredPart */
393
394 ASN1_MALLOC_ENCODE(EncKrbCredPart, buf, buf_size,
395 &enc_krb_cred_part, &len, ret);
396 free_EncKrbCredPart (&enc_krb_cred_part);
397 if (ret) {
398 free_KRB_CRED(&cred);
399 return ret;
400 }
401 if(buf_size != len)
402 krb5_abortx(context, "internal error in ASN.1 encoder");
403
404 /**
405 * Some older of the MIT gssapi library used clear-text tickets
406 * (warped inside AP-REQ encryption), use the krb5_auth_context
407 * flag KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED to support those
408 * tickets. The session key is used otherwise to encrypt the
409 * forwarded ticket.
410 */
411
412 if (auth_context->flags & KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED) {
413 cred.enc_part.etype = ENCTYPE_NULL;
414 cred.enc_part.kvno = NULL;
415 cred.enc_part.cipher.data = buf;
416 cred.enc_part.cipher.length = buf_size;
417 } else {
418 /*
419 * Here older versions then 0.7.2 of Heimdal used the local or
420 * remote subkey. That is wrong, the session key should be
421 * used. Heimdal 0.7.2 and newer have code to try both in the
422 * receiving end.
423 */
424
425 ret = krb5_crypto_init(context, auth_context->keyblock, 0, &crypto);
426 if (ret) {
427 free(buf);
428 free_KRB_CRED(&cred);
429 return ret;
430 }
431 ret = krb5_encrypt_EncryptedData (context,
432 crypto,
433 KRB5_KU_KRB_CRED,
434 buf,
435 len,
436 0,
437 &cred.enc_part);
438 free(buf);
439 krb5_crypto_destroy(context, crypto);
440 if (ret) {
441 free_KRB_CRED(&cred);
442 return ret;
443 }
444 }
445
446 ASN1_MALLOC_ENCODE(KRB_CRED, buf, buf_size, &cred, &len, ret);
447 free_KRB_CRED (&cred);
448 if (ret)
449 return ret;
450 if(buf_size != len)
451 krb5_abortx(context, "internal error in ASN.1 encoder");
452 out_data->length = len;
453 out_data->data = buf;
454 return 0;
455 out4:
456 free_EncKrbCredPart(&enc_krb_cred_part);
457 out3:
458 free_KRB_CRED(&cred);
459 out2:
460 krb5_free_creds (context, out_creds);
461 return ret;
462 }