source: heimdal/trunk/lib/krb5/rd_cred.c

Last change on this file was 1, checked in by Paul Smedley, 10 years ago

Initial commit of Heimdal 1.5.3
File size: 9.4 KB
Line 
1/*
2 * Copyright (c) 1997 - 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 "krb5_locl.h"
35
36static krb5_error_code
37compare_addrs(krb5_context context,
38 krb5_address *a,
39 krb5_address *b,
40 const char *message)
41{
42 char a_str[64], b_str[64];
43 size_t len;
44
45 if(krb5_address_compare (context, a, b))
46 return 0;
47
48 krb5_print_address (a, a_str, sizeof(a_str), &len);
49 krb5_print_address (b, b_str, sizeof(b_str), &len);
50 krb5_set_error_message(context, KRB5KRB_AP_ERR_BADADDR,
51 "%s: %s != %s", message, b_str, a_str);
52 return KRB5KRB_AP_ERR_BADADDR;
53}
54
55KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
56krb5_rd_cred(krb5_context context,
57 krb5_auth_context auth_context,
58 krb5_data *in_data,
59 krb5_creds ***ret_creds,
60 krb5_replay_data *outdata)
61{
62 krb5_error_code ret;
63 size_t len;
64 KRB_CRED cred;
65 EncKrbCredPart enc_krb_cred_part;
66 krb5_data enc_krb_cred_part_data;
67 krb5_crypto crypto;
68 size_t i;
69
70 memset(&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part));
71 krb5_data_zero(&enc_krb_cred_part_data);
72
73 if ((auth_context->flags &
74 (KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE)) &&
75 outdata == NULL)
76 return KRB5_RC_REQUIRED; /* XXX better error, MIT returns this */
77
78 *ret_creds = NULL;
79
80 ret = decode_KRB_CRED(in_data->data, in_data->length,
81 &cred, &len);
82 if(ret) {
83 krb5_clear_error_message(context);
84 return ret;
85 }
86
87 if (cred.pvno != 5) {
88 ret = KRB5KRB_AP_ERR_BADVERSION;
89 krb5_clear_error_message (context);
90 goto out;
91 }
92
93 if (cred.msg_type != krb_cred) {
94 ret = KRB5KRB_AP_ERR_MSG_TYPE;
95 krb5_clear_error_message (context);
96 goto out;
97 }
98
99 if (cred.enc_part.etype == ETYPE_NULL) {
100 /* DK: MIT GSS-API Compatibility */
101 enc_krb_cred_part_data.length = cred.enc_part.cipher.length;
102 enc_krb_cred_part_data.data = cred.enc_part.cipher.data;
103 } else {
104 /* Try both subkey and session key.
105 *
106 * RFC4120 claims we should use the session key, but Heimdal
107 * before 0.8 used the remote subkey if it was send in the
108 * auth_context.
109 */
110
111 if (auth_context->remote_subkey) {
112 ret = krb5_crypto_init(context, auth_context->remote_subkey,
113 0, &crypto);
114 if (ret)
115 goto out;
116
117 ret = krb5_decrypt_EncryptedData(context,
118 crypto,
119 KRB5_KU_KRB_CRED,
120 &cred.enc_part,
121 &enc_krb_cred_part_data);
122
123 krb5_crypto_destroy(context, crypto);
124 }
125
126 /*
127 * If there was not subkey, or we failed using subkey,
128 * retry using the session key
129 */
130 if (auth_context->remote_subkey == NULL || ret == KRB5KRB_AP_ERR_BAD_INTEGRITY)
131 {
132
133 ret = krb5_crypto_init(context, auth_context->keyblock,
134 0, &crypto);
135
136 if (ret)
137 goto out;
138
139 ret = krb5_decrypt_EncryptedData(context,
140 crypto,
141 KRB5_KU_KRB_CRED,
142 &cred.enc_part,
143 &enc_krb_cred_part_data);
144
145 krb5_crypto_destroy(context, crypto);
146 }
147 if (ret)
148 goto out;
149 }
150
151 ret = decode_EncKrbCredPart(enc_krb_cred_part_data.data,
152 enc_krb_cred_part_data.length,
153 &enc_krb_cred_part,
154 &len);
155 if (enc_krb_cred_part_data.data != cred.enc_part.cipher.data)
156 krb5_data_free(&enc_krb_cred_part_data);
157 if (ret) {
158 krb5_set_error_message(context, ret,
159 N_("Failed to decode "
160 "encrypte credential part", ""));
161 goto out;
162 }
163
164 /* check sender address */
165
166 if (enc_krb_cred_part.s_address
167 && auth_context->remote_address
168 && auth_context->remote_port) {
169 krb5_address *a;
170
171 ret = krb5_make_addrport (context, &a,
172 auth_context->remote_address,
173 auth_context->remote_port);
174 if (ret)
175 goto out;
176
177
178 ret = compare_addrs(context, a, enc_krb_cred_part.s_address,
179 N_("sender address is wrong "
180 "in received creds", ""));
181 krb5_free_address(context, a);
182 free(a);
183 if(ret)
184 goto out;
185 }
186
187 /* check receiver address */
188
189 if (enc_krb_cred_part.r_address
190 && auth_context->local_address) {
191 if(auth_context->local_port &&
192 enc_krb_cred_part.r_address->addr_type == KRB5_ADDRESS_ADDRPORT) {
193 krb5_address *a;
194 ret = krb5_make_addrport (context, &a,
195 auth_context->local_address,
196 auth_context->local_port);
197 if (ret)
198 goto out;
199
200 ret = compare_addrs(context, a, enc_krb_cred_part.r_address,
201 N_("receiver address is wrong "
202 "in received creds", ""));
203 krb5_free_address(context, a);
204 free(a);
205 if(ret)
206 goto out;
207 } else {
208 ret = compare_addrs(context, auth_context->local_address,
209 enc_krb_cred_part.r_address,
210 N_("receiver address is wrong "
211 "in received creds", ""));
212 if(ret)
213 goto out;
214 }
215 }
216
217 /* check timestamp */
218 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
219 krb5_timestamp sec;
220
221 krb5_timeofday (context, &sec);
222
223 if (enc_krb_cred_part.timestamp == NULL ||
224 enc_krb_cred_part.usec == NULL ||
225 abs(*enc_krb_cred_part.timestamp - sec)
226 > context->max_skew) {
227 krb5_clear_error_message (context);
228 ret = KRB5KRB_AP_ERR_SKEW;
229 goto out;
230 }
231 }
232
233 if ((auth_context->flags &
234 (KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE))) {
235 /* if these fields are not present in the cred-part, silently
236 return zero */
237 memset(outdata, 0, sizeof(*outdata));
238 if(enc_krb_cred_part.timestamp)
239 outdata->timestamp = *enc_krb_cred_part.timestamp;
240 if(enc_krb_cred_part.usec)
241 outdata->usec = *enc_krb_cred_part.usec;
242 if(enc_krb_cred_part.nonce)
243 outdata->seq = *enc_krb_cred_part.nonce;
244 }
245
246 /* Convert to NULL terminated list of creds */
247
248 *ret_creds = calloc(enc_krb_cred_part.ticket_info.len + 1,
249 sizeof(**ret_creds));
250
251 if (*ret_creds == NULL) {
252 ret = ENOMEM;
253 krb5_set_error_message(context, ret,
254 N_("malloc: out of memory", ""));
255 goto out;
256 }
257
258 for (i = 0; i < enc_krb_cred_part.ticket_info.len; ++i) {
259 KrbCredInfo *kci = &enc_krb_cred_part.ticket_info.val[i];
260 krb5_creds *creds;
261
262 creds = calloc(1, sizeof(*creds));
263 if(creds == NULL) {
264 ret = ENOMEM;
265 krb5_set_error_message(context, ret,
266 N_("malloc: out of memory", ""));
267 goto out;
268 }
269
270 ASN1_MALLOC_ENCODE(Ticket, creds->ticket.data, creds->ticket.length,
271 &cred.tickets.val[i], &len, ret);
272 if (ret) {
273 free(creds);
274 goto out;
275 }
276 if(creds->ticket.length != len)
277 krb5_abortx(context, "internal error in ASN.1 encoder");
278 copy_EncryptionKey (&kci->key, &creds->session);
279 if (kci->prealm && kci->pname)
280 _krb5_principalname2krb5_principal (context,
281 &creds->client,
282 *kci->pname,
283 *kci->prealm);
284 if (kci->flags)
285 creds->flags.b = *kci->flags;
286 if (kci->authtime)
287 creds->times.authtime = *kci->authtime;
288 if (kci->starttime)
289 creds->times.starttime = *kci->starttime;
290 if (kci->endtime)
291 creds->times.endtime = *kci->endtime;
292 if (kci->renew_till)
293 creds->times.renew_till = *kci->renew_till;
294 if (kci->srealm && kci->sname)
295 _krb5_principalname2krb5_principal (context,
296 &creds->server,
297 *kci->sname,
298 *kci->srealm);
299 if (kci->caddr)
300 krb5_copy_addresses (context,
301 kci->caddr,
302 &creds->addresses);
303
304 (*ret_creds)[i] = creds;
305
306 }
307 (*ret_creds)[i] = NULL;
308
309 free_KRB_CRED (&cred);
310 free_EncKrbCredPart(&enc_krb_cred_part);
311
312 return 0;
313
314 out:
315 free_EncKrbCredPart(&enc_krb_cred_part);
316 free_KRB_CRED (&cred);
317 if(*ret_creds) {
318 for(i = 0; (*ret_creds)[i]; i++)
319 krb5_free_creds(context, (*ret_creds)[i]);
320 free(*ret_creds);
321 *ret_creds = NULL;
322 }
323 return ret;
324}
325
326KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
327krb5_rd_cred2 (krb5_context context,
328 krb5_auth_context auth_context,
329 krb5_ccache ccache,
330 krb5_data *in_data)
331{
332 krb5_error_code ret;
333 krb5_creds **creds;
334 int i;
335
336 ret = krb5_rd_cred(context, auth_context, in_data, &creds, NULL);
337 if(ret)
338 return ret;
339
340 /* Store the creds in the ccache */
341
342 for(i = 0; creds && creds[i]; i++) {
343 krb5_cc_store_cred(context, ccache, creds[i]);
344 krb5_free_creds(context, creds[i]);
345 }
346 free(creds);
347 return 0;
348}
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