compat.c revision 233294 
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 */
43gss_OID_desc _gss_spnego_mskrb_mechanism_oid_desc =
44    {9, rk_UNCONST("\x2a\x86\x48\x82\xf7\x12\x01\x02\x02")};
45
46gss_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 */
52OM_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 */
95OM_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
154OM_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
199static int
200add_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
232OM_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