xref: /freebsd/crypto/heimdal/lib/gssapi/spnego/compat.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*
2  * Copyright (c) 2004, PADL Software Pty Ltd.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  *
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * 3. Neither the name of PADL Software nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include "spnego/spnego_locl.h"
34 
35 RCSID("$Id: compat.c 21866 2007-08-08 11:31:29Z lha $");
36 
37 /*
38  * Apparently Microsoft got the OID wrong, and used
39  * 1.2.840.48018.1.2.2 instead. We need both this and
40  * the correct Kerberos OID here in order to deal with
41  * this. Because this is manifest in SPNEGO only I'd
42  * prefer to deal with this here rather than inside the
43  * Kerberos mechanism.
44  */
45 gss_OID_desc _gss_spnego_mskrb_mechanism_oid_desc =
46 	{9, (void *)"\x2a\x86\x48\x82\xf7\x12\x01\x02\x02"};
47 
48 gss_OID_desc _gss_spnego_krb5_mechanism_oid_desc =
49 	{9, (void *)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02"};
50 
51 /*
52  * Allocate a SPNEGO context handle
53  */
54 OM_uint32 _gss_spnego_alloc_sec_context (OM_uint32 * minor_status,
55 					 gss_ctx_id_t *context_handle)
56 {
57     gssspnego_ctx ctx;
58 
59     ctx = calloc(1, sizeof(*ctx));
60     if (ctx == NULL) {
61 	*minor_status = ENOMEM;
62 	return GSS_S_FAILURE;
63     }
64 
65     ctx->initiator_mech_types.len = 0;
66     ctx->initiator_mech_types.val = NULL;
67     ctx->preferred_mech_type = GSS_C_NO_OID;
68     ctx->negotiated_mech_type = GSS_C_NO_OID;
69     ctx->negotiated_ctx_id = GSS_C_NO_CONTEXT;
70 
71     /*
72      * Cache these so we can return them before returning
73      * GSS_S_COMPLETE, even if the mechanism has itself
74      * completed earlier
75      */
76     ctx->mech_flags = 0;
77     ctx->mech_time_rec = 0;
78     ctx->mech_src_name = GSS_C_NO_NAME;
79     ctx->delegated_cred_id = GSS_C_NO_CREDENTIAL;
80 
81     ctx->open = 0;
82     ctx->local = 0;
83     ctx->require_mic = 0;
84     ctx->verified_mic = 0;
85 
86     HEIMDAL_MUTEX_init(&ctx->ctx_id_mutex);
87 
88     *context_handle = (gss_ctx_id_t)ctx;
89 
90     return GSS_S_COMPLETE;
91 }
92 
93 /*
94  * Free a SPNEGO context handle. The caller must have acquired
95  * the lock before this is called.
96  */
97 OM_uint32 _gss_spnego_internal_delete_sec_context
98            (OM_uint32 *minor_status,
99             gss_ctx_id_t *context_handle,
100             gss_buffer_t output_token
101            )
102 {
103     gssspnego_ctx ctx;
104     OM_uint32 ret, minor;
105 
106     *minor_status = 0;
107 
108     if (context_handle == NULL) {
109 	return GSS_S_NO_CONTEXT;
110     }
111 
112     if (output_token != GSS_C_NO_BUFFER) {
113 	output_token->length = 0;
114 	output_token->value = NULL;
115     }
116 
117     ctx = (gssspnego_ctx)*context_handle;
118     *context_handle = GSS_C_NO_CONTEXT;
119 
120     if (ctx == NULL) {
121 	return GSS_S_NO_CONTEXT;
122     }
123 
124     if (ctx->initiator_mech_types.val != NULL)
125 	free_MechTypeList(&ctx->initiator_mech_types);
126 
127     _gss_spnego_release_cred(&minor, &ctx->delegated_cred_id);
128 
129     gss_release_oid(&minor, &ctx->preferred_mech_type);
130     ctx->negotiated_mech_type = GSS_C_NO_OID;
131 
132     gss_release_name(&minor, &ctx->target_name);
133     gss_release_name(&minor, &ctx->mech_src_name);
134 
135     if (ctx->negotiated_ctx_id != GSS_C_NO_CONTEXT) {
136 	ret = gss_delete_sec_context(minor_status,
137 				     &ctx->negotiated_ctx_id,
138 				     output_token);
139 	ctx->negotiated_ctx_id = GSS_C_NO_CONTEXT;
140     } else {
141 	ret = GSS_S_COMPLETE;
142     }
143 
144     HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
145     HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
146 
147     free(ctx);
148     *context_handle = NULL;
149 
150     return ret;
151 }
152 
153 /*
154  * For compatability with the Windows SPNEGO implementation, the
155  * default is to ignore the mechListMIC unless CFX is used and
156  * a non-preferred mechanism was negotiated
157  */
158 
159 OM_uint32
160 _gss_spnego_require_mechlist_mic(OM_uint32 *minor_status,
161 				 gssspnego_ctx ctx,
162 				 int *require_mic)
163 {
164     gss_buffer_set_t buffer_set = GSS_C_NO_BUFFER_SET;
165     OM_uint32 minor;
166 
167     *minor_status = 0;
168     *require_mic = 0;
169 
170     if (ctx == NULL) {
171 	return GSS_S_COMPLETE;
172     }
173 
174     if (ctx->require_mic) {
175 	/* Acceptor requested it: mandatory to honour */
176 	*require_mic = 1;
177 	return GSS_S_COMPLETE;
178     }
179 
180     /*
181      * Check whether peer indicated implicit support for updated SPNEGO
182      * (eg. in the Kerberos case by using CFX)
183      */
184     if (gss_inquire_sec_context_by_oid(&minor, ctx->negotiated_ctx_id,
185 				       GSS_C_PEER_HAS_UPDATED_SPNEGO,
186 				       &buffer_set) == GSS_S_COMPLETE) {
187 	*require_mic = 1;
188 	gss_release_buffer_set(&minor, &buffer_set);
189     }
190 
191     /* Safe-to-omit MIC rules follow */
192     if (*require_mic) {
193 	if (gss_oid_equal(ctx->negotiated_mech_type, ctx->preferred_mech_type)) {
194 	    *require_mic = 0;
195 	} else if (gss_oid_equal(ctx->negotiated_mech_type, &_gss_spnego_krb5_mechanism_oid_desc) &&
196 		   gss_oid_equal(ctx->preferred_mech_type, &_gss_spnego_mskrb_mechanism_oid_desc)) {
197 	    *require_mic = 0;
198 	}
199     }
200 
201     return GSS_S_COMPLETE;
202 }
203 
204 static int
205 add_mech_type(gss_OID mech_type,
206 	      int includeMSCompatOID,
207 	      MechTypeList *mechtypelist)
208 {
209     MechType mech;
210     int ret;
211 
212     if (gss_oid_equal(mech_type, GSS_SPNEGO_MECHANISM))
213 	return 0;
214 
215     if (includeMSCompatOID &&
216 	gss_oid_equal(mech_type, &_gss_spnego_krb5_mechanism_oid_desc)) {
217 	ret = der_get_oid(_gss_spnego_mskrb_mechanism_oid_desc.elements,
218 			  _gss_spnego_mskrb_mechanism_oid_desc.length,
219 			  &mech,
220 			  NULL);
221 	if (ret)
222 	    return ret;
223 	ret = add_MechTypeList(mechtypelist, &mech);
224 	free_MechType(&mech);
225 	if (ret)
226 	    return ret;
227     }
228     ret = der_get_oid(mech_type->elements, mech_type->length, &mech, NULL);
229     if (ret)
230 	return ret;
231     ret = add_MechTypeList(mechtypelist, &mech);
232     free_MechType(&mech);
233     return ret;
234 }
235 
236 
237 OM_uint32
238 _gss_spnego_indicate_mechtypelist (OM_uint32 *minor_status,
239 				   gss_name_t target_name,
240 				   OM_uint32 (*func)(gss_name_t, gss_OID),
241 				   int includeMSCompatOID,
242 				   const gssspnego_cred cred_handle,
243 				   MechTypeList *mechtypelist,
244 				   gss_OID *preferred_mech)
245 {
246     gss_OID_set supported_mechs = GSS_C_NO_OID_SET;
247     gss_OID first_mech = GSS_C_NO_OID;
248     OM_uint32 ret;
249     int i;
250 
251     mechtypelist->len = 0;
252     mechtypelist->val = NULL;
253 
254     if (cred_handle != NULL) {
255 	ret = gss_inquire_cred(minor_status,
256 			       cred_handle->negotiated_cred_id,
257 			       NULL,
258 			       NULL,
259 			       NULL,
260 			       &supported_mechs);
261     } else {
262 	ret = gss_indicate_mechs(minor_status, &supported_mechs);
263     }
264 
265     if (ret != GSS_S_COMPLETE) {
266 	return ret;
267     }
268 
269     if (supported_mechs->count == 0) {
270 	*minor_status = ENOENT;
271 	gss_release_oid_set(minor_status, &supported_mechs);
272 	return GSS_S_FAILURE;
273     }
274 
275     ret = (*func)(target_name, GSS_KRB5_MECHANISM);
276     if (ret == GSS_S_COMPLETE) {
277 	ret = add_mech_type(GSS_KRB5_MECHANISM,
278 			    includeMSCompatOID,
279 			    mechtypelist);
280 	if (!GSS_ERROR(ret))
281 	    first_mech = GSS_KRB5_MECHANISM;
282     }
283     ret = GSS_S_COMPLETE;
284 
285     for (i = 0; i < supported_mechs->count; i++) {
286 	OM_uint32 subret;
287 	if (gss_oid_equal(&supported_mechs->elements[i], GSS_SPNEGO_MECHANISM))
288 	    continue;
289 	if (gss_oid_equal(&supported_mechs->elements[i], GSS_KRB5_MECHANISM))
290 	    continue;
291 
292 	subret = (*func)(target_name, &supported_mechs->elements[i]);
293 	if (subret != GSS_S_COMPLETE)
294 	    continue;
295 
296 	ret = add_mech_type(&supported_mechs->elements[i],
297 			    includeMSCompatOID,
298 			    mechtypelist);
299 	if (ret != 0) {
300 	    *minor_status = ret;
301 	    ret = GSS_S_FAILURE;
302 	    break;
303 	}
304 	if (first_mech == GSS_C_NO_OID)
305 	    first_mech = &supported_mechs->elements[i];
306     }
307 
308     if (mechtypelist->len == 0) {
309 	gss_release_oid_set(minor_status, &supported_mechs);
310 	*minor_status = 0;
311 	return GSS_S_BAD_MECH;
312     }
313 
314     if (preferred_mech != NULL) {
315 	ret = gss_duplicate_oid(minor_status, first_mech, preferred_mech);
316 	if (ret != GSS_S_COMPLETE)
317 	    free_MechTypeList(mechtypelist);
318     }
319     gss_release_oid_set(minor_status, &supported_mechs);
320 
321     return ret;
322 }
323