xref: /netbsd-src/crypto/external/bsd/heimdal/dist/lib/kafs/afskrb5.c (revision f0fde9902fd4d72ded2807793acc7bfaa1ebf243)
1 /*	$NetBSD: afskrb5.c,v 1.2 2017/01/28 21:31:49 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1995-2003 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "kafs_locl.h"
37 
38 struct krb5_kafs_data {
39     krb5_context context;
40     krb5_ccache id;
41     krb5_const_realm realm;
42 };
43 
44 enum {
45     KAFS_RXKAD_2B_KVNO = 213,
46     KAFS_RXKAD_K5_KVNO = 256
47 };
48 
49 static int
50 v5_to_kt(krb5_creds *cred, uid_t uid, struct kafs_token *kt, int local524)
51 {
52     int kvno, ret;
53 
54     kt->ticket = NULL;
55 
56     if (local524) {
57 	Ticket t;
58 	unsigned char *buf;
59 	size_t buf_len;
60 	size_t len;
61 
62 	kvno = KAFS_RXKAD_2B_KVNO;
63 
64 	ret = decode_Ticket(cred->ticket.data, cred->ticket.length, &t, &len);
65 	if (ret)
66 	    return ret;
67 	if (t.tkt_vno != 5)
68 	    return -1;
69 
70 	ASN1_MALLOC_ENCODE(EncryptedData, buf, buf_len, &t.enc_part,
71 			   &len, ret);
72 	free_Ticket(&t);
73 	if (ret)
74 	    return ret;
75 	if(buf_len != len) {
76 	    free(buf);
77 	    return KRB5KRB_ERR_GENERIC;
78 	}
79 
80 	kt->ticket = buf;
81 	kt->ticket_len = buf_len;
82 
83     } else {
84 	kvno = KAFS_RXKAD_K5_KVNO;
85 	kt->ticket = malloc(cred->ticket.length);
86 	if (kt->ticket == NULL)
87 	    return ENOMEM;
88 	kt->ticket_len = cred->ticket.length;
89 	memcpy(kt->ticket, cred->ticket.data, kt->ticket_len);
90 
91 	ret = 0;
92     }
93 
94 
95     /*
96      * Build a struct ClearToken
97      */
98 
99     ret = _kafs_derive_des_key(cred->session.keytype,
100 			       cred->session.keyvalue.data,
101 			       cred->session.keyvalue.length,
102 			       kt->ct.HandShakeKey);
103     if (ret) {
104 	free(kt->ticket);
105 	kt->ticket = NULL;
106 	return ret;
107     }
108     kt->ct.AuthHandle = kvno;
109     kt->ct.ViceId = uid;
110     kt->ct.BeginTimestamp = cred->times.starttime;
111     kt->ct.EndTimestamp = cred->times.endtime;
112 
113     _kafs_fixup_viceid(&kt->ct, uid);
114 
115     return 0;
116 }
117 
118 static krb5_error_code
119 v5_convert(krb5_context context, krb5_ccache id,
120 	   krb5_creds *cred, uid_t uid,
121 	   const char *cell,
122 	   struct kafs_token *kt)
123 {
124     krb5_error_code ret;
125     char *c, *val;
126 
127     c = strdup(cell);
128     if (c == NULL)
129 	return ENOMEM;
130     _kafs_foldup(c, c);
131     krb5_appdefault_string (context, "libkafs",
132 			    c,
133 			    "afs-use-524", "2b", &val);
134     free(c);
135 
136     if (strcasecmp(val, "local") == 0 ||
137 	strcasecmp(val, "2b") == 0)
138 	ret = v5_to_kt(cred, uid, kt, 1);
139     else
140 	ret = v5_to_kt(cred, uid, kt, 0);
141 
142     free(val);
143     return ret;
144 }
145 
146 
147 /*
148  *
149  */
150 
151 static int
152 get_cred(struct kafs_data *data, const char *name, const char *inst,
153 	 const char *realm, uid_t uid, struct kafs_token *kt)
154 {
155     krb5_error_code ret;
156     krb5_creds in_creds, *out_creds;
157     struct krb5_kafs_data *d = data->data;
158     int invalid;
159 
160     memset(&in_creds, 0, sizeof(in_creds));
161 
162     ret = krb5_make_principal(d->context, &in_creds.server,
163 			      realm, name, inst, NULL);
164     if(ret)
165 	return ret;
166     ret = krb5_cc_get_principal(d->context, d->id, &in_creds.client);
167     if(ret){
168 	krb5_free_principal(d->context, in_creds.server);
169 	return ret;
170     }
171 
172     /* check if des is disable, and in that case enable it for afs */
173     invalid = krb5_enctype_valid(d->context, ETYPE_DES_CBC_CRC);
174     if (invalid)
175 	krb5_enctype_enable(d->context, ETYPE_DES_CBC_CRC);
176 
177     ret = krb5_get_credentials(d->context, 0, d->id, &in_creds, &out_creds);
178 
179     if (invalid)
180 	krb5_enctype_disable(d->context, ETYPE_DES_CBC_CRC);
181 
182     krb5_free_principal(d->context, in_creds.server);
183     krb5_free_principal(d->context, in_creds.client);
184     if(ret)
185 	return ret;
186 
187     ret = v5_convert(d->context, d->id, out_creds, uid,
188 		     (inst != NULL && inst[0] != '\0') ? inst : realm, kt);
189     krb5_free_creds(d->context, out_creds);
190 
191     return ret;
192 }
193 
194 static const char *
195 get_error(struct kafs_data *data, int error)
196 {
197     struct krb5_kafs_data *d = data->data;
198     return krb5_get_error_message(d->context, error);
199 }
200 
201 static void
202 free_error(struct kafs_data *data, const char *str)
203 {
204     struct krb5_kafs_data *d = data->data;
205     krb5_free_error_message(d->context, str);
206 }
207 
208 static krb5_error_code
209 afslog_uid_int(struct kafs_data *data, const char *cell, const char *rh,
210 	       uid_t uid, const char *homedir)
211 {
212     krb5_error_code ret;
213     struct kafs_token kt;
214     krb5_principal princ;
215     const char *trealm; /* ticket realm */
216     struct krb5_kafs_data *d = data->data;
217 
218     if (cell == 0 || cell[0] == 0)
219 	return _kafs_afslog_all_local_cells (data, uid, homedir);
220 
221     ret = krb5_cc_get_principal (d->context, d->id, &princ);
222     if (ret)
223 	return ret;
224 
225     trealm = krb5_principal_get_realm (d->context, princ);
226 
227     kt.ticket = NULL;
228     ret = _kafs_get_cred(data, cell, d->realm, trealm, uid, &kt);
229     krb5_free_principal (d->context, princ);
230 
231     if(ret == 0) {
232 	ret = kafs_settoken_rxkad(cell, &kt.ct, kt.ticket, kt.ticket_len);
233 	free(kt.ticket);
234     }
235     return ret;
236 }
237 
238 static char *
239 get_realm(struct kafs_data *data, const char *host)
240 {
241     struct krb5_kafs_data *d = data->data;
242     krb5_realm *realms;
243     char *r;
244     if(krb5_get_host_realm(d->context, host, &realms))
245 	return NULL;
246     r = strdup(realms[0]);
247     krb5_free_host_realm(d->context, realms);
248     return r;
249 }
250 
251 krb5_error_code
252 krb5_afslog_uid_home(krb5_context context,
253 		     krb5_ccache id,
254 		     const char *cell,
255 		     krb5_const_realm realm,
256 		     uid_t uid,
257 		     const char *homedir)
258 {
259     struct kafs_data kd;
260     struct krb5_kafs_data d;
261     krb5_error_code ret;
262 
263     kd.name = "krb5";
264     kd.afslog_uid = afslog_uid_int;
265     kd.get_cred = get_cred;
266     kd.get_realm = get_realm;
267     kd.get_error = get_error;
268     kd.free_error = free_error;
269     kd.data = &d;
270     if (context == NULL) {
271 	ret = krb5_init_context(&d.context);
272 	if (ret)
273 	    return ret;
274     } else
275 	d.context = context;
276     if (id == NULL) {
277 	ret = krb5_cc_default(d.context, &d.id);
278 	if (ret)
279 	    goto out;
280     } else
281 	d.id = id;
282     d.realm = realm;
283     ret = afslog_uid_int(&kd, cell, 0, uid, homedir);
284     if (id == NULL)
285 	krb5_cc_close(context, d.id);
286  out:
287     if (context == NULL)
288 	krb5_free_context(d.context);
289     return ret;
290 }
291 
292 krb5_error_code
293 krb5_afslog_uid(krb5_context context,
294 		krb5_ccache id,
295 		const char *cell,
296 		krb5_const_realm realm,
297 		uid_t uid)
298 {
299     return krb5_afslog_uid_home (context, id, cell, realm, uid, NULL);
300 }
301 
302 krb5_error_code
303 krb5_afslog(krb5_context context,
304 	    krb5_ccache id,
305 	    const char *cell,
306 	    krb5_const_realm realm)
307 {
308     return krb5_afslog_uid (context, id, cell, realm, getuid());
309 }
310 
311 krb5_error_code
312 krb5_afslog_home(krb5_context context,
313 		 krb5_ccache id,
314 		 const char *cell,
315 		 krb5_const_realm realm,
316 		 const char *homedir)
317 {
318     return krb5_afslog_uid_home (context, id, cell, realm, getuid(), homedir);
319 }
320 
321 /*
322  *
323  */
324 
325 krb5_error_code
326 krb5_realm_of_cell(const char *cell, char **realm)
327 {
328     struct kafs_data kd;
329 
330     kd.name = "krb5";
331     kd.get_realm = get_realm;
332     kd.get_error = get_error;
333     kd.free_error = free_error;
334     return _kafs_realm_of_cell(&kd, cell, realm);
335 }
336 
337 /*
338  *
339  */
340 
341 int
342 kafs_settoken5(krb5_context context, const char *cell, uid_t uid,
343 	       krb5_creds *cred)
344 {
345     struct kafs_token kt;
346     int ret;
347 
348     ret = v5_convert(context, NULL, cred, uid, cell, &kt);
349     if (ret)
350 	return ret;
351 
352     ret = kafs_settoken_rxkad(cell, &kt.ct, kt.ticket, kt.ticket_len);
353 
354     free(kt.ticket);
355 
356     return ret;
357 }
358