xref: /freebsd/crypto/heimdal/lib/krb5/convert_creds.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
1 /*
2  * Copyright (c) 1997 - 2002 Kungliga Tekniska H�gskolan
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 RCSID("$Id: convert_creds.c,v 1.26 2003/03/18 03:11:16 lha Exp $");
36 
37 #include "krb5-v4compat.h"
38 
39 static krb5_error_code
40 check_ticket_flags(TicketFlags f)
41 {
42     return 0; /* maybe add some more tests here? */
43 }
44 
45 /* include this here, to avoid dependencies on libkrb */
46 
47 static const int _tkt_lifetimes[TKTLIFENUMFIXED] = {
48    38400,   41055,   43894,   46929,   50174,   53643,   57352,   61318,
49    65558,   70091,   74937,   80119,   85658,   91581,   97914,  104684,
50   111922,  119661,  127935,  136781,  146239,  156350,  167161,  178720,
51   191077,  204289,  218415,  233517,  249664,  266926,  285383,  305116,
52   326213,  348769,  372885,  398668,  426234,  455705,  487215,  520904,
53   556921,  595430,  636601,  680618,  727680,  777995,  831789,  889303,
54   950794, 1016537, 1086825, 1161973, 1242318, 1328218, 1420057, 1518247,
55  1623226, 1735464, 1855462, 1983758, 2120925, 2267576, 2424367, 2592000
56 };
57 
58 int
59 _krb5_krb_time_to_life(time_t start, time_t end)
60 {
61     int i;
62     time_t life = end - start;
63 
64     if (life > MAXTKTLIFETIME || life <= 0)
65 	return 0;
66 #if 0
67     if (krb_no_long_lifetimes)
68 	return (life + 5*60 - 1)/(5*60);
69 #endif
70 
71     if (end >= NEVERDATE)
72 	return TKTLIFENOEXPIRE;
73     if (life < _tkt_lifetimes[0])
74 	return (life + 5*60 - 1)/(5*60);
75     for (i=0; i<TKTLIFENUMFIXED; i++)
76 	if (life <= _tkt_lifetimes[i])
77 	    return i + TKTLIFEMINFIXED;
78     return 0;
79 
80 }
81 
82 time_t
83 _krb5_krb_life_to_time(int start, int life_)
84 {
85     unsigned char life = (unsigned char) life_;
86 
87 #if 0
88     if (krb_no_long_lifetimes)
89 	return start + life*5*60;
90 #endif
91 
92     if (life == TKTLIFENOEXPIRE)
93 	return NEVERDATE;
94     if (life < TKTLIFEMINFIXED)
95 	return start + life*5*60;
96     if (life > TKTLIFEMAXFIXED)
97 	return start + MAXTKTLIFETIME;
98     return start + _tkt_lifetimes[life - TKTLIFEMINFIXED];
99 }
100 
101 
102 /* Convert the v5 credentials in `in_cred' to v4-dito in `v4creds'.
103  * This is done by sending them to the 524 function in the KDC.  If
104  * `in_cred' doesn't contain a DES session key, then a new one is
105  * gotten from the KDC and stored in the cred cache `ccache'.
106  */
107 
108 krb5_error_code
109 krb524_convert_creds_kdc(krb5_context context,
110 			 krb5_creds *in_cred,
111 			 struct credentials *v4creds)
112 {
113     krb5_error_code ret;
114     krb5_data reply;
115     krb5_storage *sp;
116     int32_t tmp;
117     krb5_data ticket;
118     char realm[REALM_SZ];
119     krb5_creds *v5_creds = in_cred;
120 
121     ret = check_ticket_flags(v5_creds->flags.b);
122     if(ret)
123 	goto out2;
124 
125     {
126 	krb5_krbhst_handle handle;
127 
128 	ret = krb5_krbhst_init(context,
129 			       *krb5_princ_realm(context,
130 						v5_creds->server),
131 			       KRB5_KRBHST_KRB524,
132 			       &handle);
133 	if (ret)
134 	    goto out2;
135 
136 	ret = krb5_sendto (context,
137 			   &v5_creds->ticket,
138 			   handle,
139 			   &reply);
140 	krb5_krbhst_free(context, handle);
141 	if (ret)
142 	    goto out2;
143     }
144     sp = krb5_storage_from_mem(reply.data, reply.length);
145     if(sp == NULL) {
146 	ret = ENOMEM;
147 	krb5_set_error_string (context, "malloc: out of memory");
148 	goto out2;
149     }
150     krb5_ret_int32(sp, &tmp);
151     ret = tmp;
152     if(ret == 0) {
153 	memset(v4creds, 0, sizeof(*v4creds));
154 	ret = krb5_ret_int32(sp, &tmp);
155 	if(ret)
156 	    goto out;
157 	v4creds->kvno = tmp;
158 	ret = krb5_ret_data(sp, &ticket);
159 	if(ret)
160 	    goto out;
161 	v4creds->ticket_st.length = ticket.length;
162 	memcpy(v4creds->ticket_st.dat, ticket.data, ticket.length);
163 	krb5_data_free(&ticket);
164 	ret = krb5_524_conv_principal(context,
165 				      v5_creds->server,
166 				      v4creds->service,
167 				      v4creds->instance,
168 				      v4creds->realm);
169 	if(ret)
170 	    goto out;
171 	v4creds->issue_date = v5_creds->times.starttime;
172 	v4creds->lifetime = _krb5_krb_time_to_life(v4creds->issue_date,
173 						   v5_creds->times.endtime);
174 	ret = krb5_524_conv_principal(context, v5_creds->client,
175 				      v4creds->pname,
176 				      v4creds->pinst,
177 				      realm);
178 	if(ret)
179 	    goto out;
180 	memcpy(v4creds->session, v5_creds->session.keyvalue.data, 8);
181     } else {
182 	krb5_set_error_string(context, "converting credentials: %s",
183 			      krb5_get_err_text(context, ret));
184     }
185 out:
186     krb5_storage_free(sp);
187     krb5_data_free(&reply);
188 out2:
189     if (v5_creds != in_cred)
190 	krb5_free_creds (context, v5_creds);
191     return ret;
192 }
193 
194 krb5_error_code
195 krb524_convert_creds_kdc_ccache(krb5_context context,
196 				krb5_ccache ccache,
197 				krb5_creds *in_cred,
198 				struct credentials *v4creds)
199 {
200     krb5_error_code ret;
201     krb5_creds *v5_creds = in_cred;
202     krb5_keytype keytype;
203 
204     keytype = v5_creds->session.keytype;
205 
206     if (keytype != ENCTYPE_DES_CBC_CRC) {
207 	/* MIT krb524d doesn't like nothing but des-cbc-crc tickets,
208            so go get one */
209 	krb5_creds template;
210 
211 	memset (&template, 0, sizeof(template));
212 	template.session.keytype = ENCTYPE_DES_CBC_CRC;
213 	ret = krb5_copy_principal (context, in_cred->client, &template.client);
214 	if (ret) {
215 	    krb5_free_creds_contents (context, &template);
216 	    return ret;
217 	}
218 	ret = krb5_copy_principal (context, in_cred->server, &template.server);
219 	if (ret) {
220 	    krb5_free_creds_contents (context, &template);
221 	    return ret;
222 	}
223 
224 	ret = krb5_get_credentials (context, 0, ccache,
225 				    &template, &v5_creds);
226 	krb5_free_creds_contents (context, &template);
227 	if (ret)
228 	    return ret;
229     }
230 
231     ret = krb524_convert_creds_kdc(context, v5_creds, v4creds);
232 
233     if (v5_creds != in_cred)
234 	krb5_free_creds (context, v5_creds);
235     return ret;
236 }
237