xref: /freebsd/crypto/heimdal/lib/gssapi/spnego/compat.c (revision b740c88bfb6453416926271c089262e7164dace3)
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_locl.h"
34 
35 /*
36  * Apparently Microsoft got the OID wrong, and used
37  * 1.2.840.48018.1.2.2 instead. We need both this and
38  * the correct Kerberos OID here in order to deal with
39  * this. Because this is manifest in SPNEGO only I'd
40  * prefer to deal with this here rather than inside the
41  * Kerberos mechanism.
42  */
43 gss_OID_desc _gss_spnego_mskrb_mechanism_oid_desc =
44     {9, rk_UNCONST("\x2a\x86\x48\x82\xf7\x12\x01\x02\x02")};
45 
46 gss_OID_desc _gss_spnego_krb5_mechanism_oid_desc =
47     {9, rk_UNCONST("\x2a\x86\x48\x86\xf7\x12\x01\x02\x02")};
48 
49 /*
50  * Allocate a SPNEGO context handle
51  */
52 OM_uint32 GSSAPI_CALLCONV
53 _gss_spnego_alloc_sec_context (OM_uint32 * minor_status,
54 			       gss_ctx_id_t *context_handle)
55 {
56     gssspnego_ctx ctx;
57 
58     ctx = calloc(1, sizeof(*ctx));
59     if (ctx == NULL) {
60 	*minor_status = ENOMEM;
61 	return GSS_S_FAILURE;
62     }
63 
64     ctx->initiator_mech_types.len = 0;
65     ctx->initiator_mech_types.val = NULL;
66     ctx->preferred_mech_type = GSS_C_NO_OID;
67     ctx->negotiated_mech_type = GSS_C_NO_OID;
68     ctx->negotiated_ctx_id = GSS_C_NO_CONTEXT;
69 
70     /*
71      * Cache these so we can return them before returning
72      * GSS_S_COMPLETE, even if the mechanism has itself
73      * completed earlier
74      */
75     ctx->mech_flags = 0;
76     ctx->mech_time_rec = 0;
77     ctx->mech_src_name = GSS_C_NO_NAME;
78 
79     ctx->open = 0;
80     ctx->local = 0;
81     ctx->require_mic = 0;
82     ctx->verified_mic = 0;
83 
84     HEIMDAL_MUTEX_init(&ctx->ctx_id_mutex);
85 
86     *context_handle = (gss_ctx_id_t)ctx;
87 
88     return GSS_S_COMPLETE;
89 }
90 
91 /*
92  * Free a SPNEGO context handle. The caller must have acquired
93  * the lock before this is called.
94  */
95 OM_uint32 GSSAPI_CALLCONV _gss_spnego_internal_delete_sec_context
96            (OM_uint32 *minor_status,
97             gss_ctx_id_t *context_handle,
98             gss_buffer_t output_token
99            )
100 {
101     gssspnego_ctx ctx;
102     OM_uint32 ret, minor;
103 
104     *minor_status = 0;
105 
106     if (context_handle == NULL) {
107 	return GSS_S_NO_CONTEXT;
108     }
109 
110     if (output_token != GSS_C_NO_BUFFER) {
111 	output_token->length = 0;
112 	output_token->value = NULL;
113     }
114 
115     ctx = (gssspnego_ctx)*context_handle;
116     *context_handle = GSS_C_NO_CONTEXT;
117 
118     if (ctx == NULL) {
119 	return GSS_S_NO_CONTEXT;
120     }
121 
122     if (ctx->initiator_mech_types.val != NULL)
123 	free_MechTypeList(&ctx->initiator_mech_types);
124 
125     gss_release_oid(&minor, &ctx->preferred_mech_type);
126     ctx->negotiated_mech_type = GSS_C_NO_OID;
127 
128     gss_release_name(&minor, &ctx->target_name);
129     gss_release_name(&minor, &ctx->mech_src_name);
130 
131     if (ctx->negotiated_ctx_id != GSS_C_NO_CONTEXT) {
132 	ret = gss_delete_sec_context(minor_status,
133 				     &ctx->negotiated_ctx_id,
134 				     output_token);
135 	ctx->negotiated_ctx_id = GSS_C_NO_CONTEXT;
136     } else {
137 	ret = GSS_S_COMPLETE;
138     }
139 
140     HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
141     HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
142 
143     free(ctx);
144 
145     return ret;
146 }
147 
148 /*
149  * For compatability with the Windows SPNEGO implementation, the
150  * default is to ignore the mechListMIC unless CFX is used and
151  * a non-preferred mechanism was negotiated
152  */
153 
154 OM_uint32 GSSAPI_CALLCONV
155 _gss_spnego_require_mechlist_mic(OM_uint32 *minor_status,
156 				 gssspnego_ctx ctx,
157 				 int *require_mic)
158 {
159     gss_buffer_set_t buffer_set = GSS_C_NO_BUFFER_SET;
160     OM_uint32 minor;
161 
162     *minor_status = 0;
163     *require_mic = 0;
164 
165     if (ctx == NULL) {
166 	return GSS_S_COMPLETE;
167     }
168 
169     if (ctx->require_mic) {
170 	/* Acceptor requested it: mandatory to honour */
171 	*require_mic = 1;
172 	return GSS_S_COMPLETE;
173     }
174 
175     /*
176      * Check whether peer indicated implicit support for updated SPNEGO
177      * (eg. in the Kerberos case by using CFX)
178      */
179     if (gss_inquire_sec_context_by_oid(&minor, ctx->negotiated_ctx_id,
180 				       GSS_C_PEER_HAS_UPDATED_SPNEGO,
181 				       &buffer_set) == GSS_S_COMPLETE) {
182 	*require_mic = 1;
183 	gss_release_buffer_set(&minor, &buffer_set);
184     }
185 
186     /* Safe-to-omit MIC rules follow */
187     if (*require_mic) {
188 	if (gss_oid_equal(ctx->negotiated_mech_type, ctx->preferred_mech_type)) {
189 	    *require_mic = 0;
190 	} else if (gss_oid_equal(ctx->negotiated_mech_type, &_gss_spnego_krb5_mechanism_oid_desc) &&
191 		   gss_oid_equal(ctx->preferred_mech_type, &_gss_spnego_mskrb_mechanism_oid_desc)) {
192 	    *require_mic = 0;
193 	}
194     }
195 
196     return GSS_S_COMPLETE;
197 }
198 
199 static int
200 add_mech_type(gss_OID mech_type,
201 	      int includeMSCompatOID,
202 	      MechTypeList *mechtypelist)
203 {
204     MechType mech;
205     int ret;
206 
207     if (gss_oid_equal(mech_type, GSS_SPNEGO_MECHANISM))
208 	return 0;
209 
210     if (includeMSCompatOID &&
211 	gss_oid_equal(mech_type, &_gss_spnego_krb5_mechanism_oid_desc)) {
212 	ret = der_get_oid(_gss_spnego_mskrb_mechanism_oid_desc.elements,
213 			  _gss_spnego_mskrb_mechanism_oid_desc.length,
214 			  &mech,
215 			  NULL);
216 	if (ret)
217 	    return ret;
218 	ret = add_MechTypeList(mechtypelist, &mech);
219 	free_MechType(&mech);
220 	if (ret)
221 	    return ret;
222     }
223     ret = der_get_oid(mech_type->elements, mech_type->length, &mech, NULL);
224     if (ret)
225 	return ret;
226     ret = add_MechTypeList(mechtypelist, &mech);
227     free_MechType(&mech);
228     return ret;
229 }
230 
231 
232 OM_uint32 GSSAPI_CALLCONV
233 _gss_spnego_indicate_mechtypelist (OM_uint32 *minor_status,
234 				   gss_name_t target_name,
235 				   OM_uint32 (*func)(gss_name_t, gss_OID),
236 				   int includeMSCompatOID,
237 				   const gss_cred_id_t cred_handle,
238 				   MechTypeList *mechtypelist,
239 				   gss_OID *preferred_mech)
240 {
241     gss_OID_set supported_mechs = GSS_C_NO_OID_SET;
242     gss_OID first_mech = GSS_C_NO_OID;
243     OM_uint32 ret;
244     size_t i;
245 
246     mechtypelist->len = 0;
247     mechtypelist->val = NULL;
248 
249     if (cred_handle) {
250 	ret = gss_inquire_cred(minor_status,
251 			       cred_handle,
252 			       NULL,
253 			       NULL,
254 			       NULL,
255 			       &supported_mechs);
256     } else {
257 	ret = gss_indicate_mechs(minor_status, &supported_mechs);
258     }
259 
260     if (ret != GSS_S_COMPLETE) {
261 	return ret;
262     }
263 
264     if (supported_mechs->count == 0) {
265 	*minor_status = ENOENT;
266 	gss_release_oid_set(minor_status, &supported_mechs);
267 	return GSS_S_FAILURE;
268     }
269 
270     ret = (*func)(target_name, GSS_KRB5_MECHANISM);
271     if (ret == GSS_S_COMPLETE) {
272 	ret = add_mech_type(GSS_KRB5_MECHANISM,
273 			    includeMSCompatOID,
274 			    mechtypelist);
275 	if (!GSS_ERROR(ret))
276 	    first_mech = GSS_KRB5_MECHANISM;
277     }
278     ret = GSS_S_COMPLETE;
279 
280     for (i = 0; i < supported_mechs->count; i++) {
281 	OM_uint32 subret;
282 	if (gss_oid_equal(&supported_mechs->elements[i], GSS_SPNEGO_MECHANISM))
283 	    continue;
284 	if (gss_oid_equal(&supported_mechs->elements[i], GSS_KRB5_MECHANISM))
285 	    continue;
286 
287 	subret = (*func)(target_name, &supported_mechs->elements[i]);
288 	if (subret != GSS_S_COMPLETE)
289 	    continue;
290 
291 	ret = add_mech_type(&supported_mechs->elements[i],
292 			    includeMSCompatOID,
293 			    mechtypelist);
294 	if (ret != 0) {
295 	    *minor_status = ret;
296 	    ret = GSS_S_FAILURE;
297 	    break;
298 	}
299 	if (first_mech == GSS_C_NO_OID)
300 	    first_mech = &supported_mechs->elements[i];
301     }
302 
303     if (mechtypelist->len == 0) {
304 	gss_release_oid_set(minor_status, &supported_mechs);
305 	*minor_status = 0;
306 	return GSS_S_BAD_MECH;
307     }
308 
309     if (preferred_mech != NULL) {
310 	ret = gss_duplicate_oid(minor_status, first_mech, preferred_mech);
311 	if (ret != GSS_S_COMPLETE)
312 	    free_MechTypeList(mechtypelist);
313     }
314     gss_release_oid_set(minor_status, &supported_mechs);
315 
316     return ret;
317 }
318