Home | History | Annotate | Line # | Download | only in spnego
      1 /*	$NetBSD: compat.c,v 1.2 2017/01/28 21:31:47 christos Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2004, PADL Software Pty Ltd.
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  *
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  *
     14  * 2. Redistributions in binary form must reproduce the above copyright
     15  *    notice, this list of conditions and the following disclaimer in the
     16  *    documentation and/or other materials provided with the distribution.
     17  *
     18  * 3. Neither the name of PADL Software nor the names of its contributors
     19  *    may be used to endorse or promote products derived from this software
     20  *    without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
     26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  */
     34 
     35 #include "spnego_locl.h"
     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, rk_UNCONST("\x2a\x86\x48\x82\xf7\x12\x01\x02\x02")};
     47 
     48 gss_OID_desc _gss_spnego_krb5_mechanism_oid_desc =
     49     {9, rk_UNCONST("\x2a\x86\x48\x86\xf7\x12\x01\x02\x02")};
     50 
     51 /*
     52  * Allocate a SPNEGO context handle
     53  */
     54 OM_uint32 GSSAPI_CALLCONV
     55 _gss_spnego_alloc_sec_context (OM_uint32 * minor_status,
     56 			       gss_ctx_id_t *context_handle)
     57 {
     58     gssspnego_ctx ctx;
     59 
     60     ctx = calloc(1, sizeof(*ctx));
     61     if (ctx == NULL) {
     62 	*minor_status = ENOMEM;
     63 	return GSS_S_FAILURE;
     64     }
     65 
     66     ctx->initiator_mech_types.len = 0;
     67     ctx->initiator_mech_types.val = NULL;
     68     ctx->preferred_mech_type = GSS_C_NO_OID;
     69     ctx->negotiated_mech_type = GSS_C_NO_OID;
     70     ctx->negotiated_ctx_id = GSS_C_NO_CONTEXT;
     71 
     72     /*
     73      * Cache these so we can return them before returning
     74      * GSS_S_COMPLETE, even if the mechanism has itself
     75      * completed earlier
     76      */
     77     ctx->mech_flags = 0;
     78     ctx->mech_time_rec = 0;
     79     ctx->mech_src_name = GSS_C_NO_NAME;
     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 GSSAPI_CALLCONV _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_release_oid(&minor, &ctx->preferred_mech_type);
    128     ctx->negotiated_mech_type = GSS_C_NO_OID;
    129 
    130     gss_release_name(&minor, &ctx->target_name);
    131     gss_release_name(&minor, &ctx->mech_src_name);
    132 
    133     if (ctx->negotiated_ctx_id != GSS_C_NO_CONTEXT) {
    134 	ret = gss_delete_sec_context(minor_status,
    135 				     &ctx->negotiated_ctx_id,
    136 				     output_token);
    137 	ctx->negotiated_ctx_id = GSS_C_NO_CONTEXT;
    138     } else {
    139 	ret = GSS_S_COMPLETE;
    140     }
    141 
    142     HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
    143     HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
    144 
    145     free(ctx);
    146 
    147     return ret;
    148 }
    149 
    150 /*
    151  * For compatability with the Windows SPNEGO implementation, the
    152  * default is to ignore the mechListMIC unless CFX is used and
    153  * a non-preferred mechanism was negotiated
    154  */
    155 
    156 OM_uint32 GSSAPI_CALLCONV
    157 _gss_spnego_require_mechlist_mic(OM_uint32 *minor_status,
    158 				 gssspnego_ctx ctx,
    159 				 int *require_mic)
    160 {
    161     gss_buffer_set_t buffer_set = GSS_C_NO_BUFFER_SET;
    162     OM_uint32 minor;
    163 
    164     *minor_status = 0;
    165     *require_mic = 0;
    166 
    167     if (ctx == NULL) {
    168 	return GSS_S_COMPLETE;
    169     }
    170 
    171     if (ctx->require_mic) {
    172 	/* Acceptor requested it: mandatory to honour */
    173 	*require_mic = 1;
    174 	return GSS_S_COMPLETE;
    175     }
    176 
    177     /*
    178      * Check whether peer indicated implicit support for updated SPNEGO
    179      * (eg. in the Kerberos case by using CFX)
    180      */
    181     if (gss_inquire_sec_context_by_oid(&minor, ctx->negotiated_ctx_id,
    182 				       GSS_C_PEER_HAS_UPDATED_SPNEGO,
    183 				       &buffer_set) == GSS_S_COMPLETE) {
    184 	*require_mic = 1;
    185 	gss_release_buffer_set(&minor, &buffer_set);
    186     }
    187 
    188     /* Safe-to-omit MIC rules follow */
    189     if (*require_mic) {
    190 	if (gss_oid_equal(ctx->negotiated_mech_type, ctx->preferred_mech_type)) {
    191 	    *require_mic = 0;
    192 	} else if (gss_oid_equal(ctx->negotiated_mech_type, &_gss_spnego_krb5_mechanism_oid_desc) &&
    193 		   gss_oid_equal(ctx->preferred_mech_type, &_gss_spnego_mskrb_mechanism_oid_desc)) {
    194 	    *require_mic = 0;
    195 	}
    196     }
    197 
    198     return GSS_S_COMPLETE;
    199 }
    200 
    201 static int
    202 add_mech_type(gss_OID mech_type,
    203 	      int includeMSCompatOID,
    204 	      MechTypeList *mechtypelist)
    205 {
    206     MechType mech;
    207     int ret;
    208 
    209     if (gss_oid_equal(mech_type, GSS_SPNEGO_MECHANISM))
    210 	return 0;
    211 
    212     if (includeMSCompatOID &&
    213 	gss_oid_equal(mech_type, &_gss_spnego_krb5_mechanism_oid_desc)) {
    214 	ret = der_get_oid(_gss_spnego_mskrb_mechanism_oid_desc.elements,
    215 			  _gss_spnego_mskrb_mechanism_oid_desc.length,
    216 			  &mech,
    217 			  NULL);
    218 	if (ret)
    219 	    return ret;
    220 	ret = add_MechTypeList(mechtypelist, &mech);
    221 	free_MechType(&mech);
    222 	if (ret)
    223 	    return ret;
    224     }
    225     ret = der_get_oid(mech_type->elements, mech_type->length, &mech, NULL);
    226     if (ret)
    227 	return ret;
    228     ret = add_MechTypeList(mechtypelist, &mech);
    229     free_MechType(&mech);
    230     return ret;
    231 }
    232 
    233 
    234 OM_uint32 GSSAPI_CALLCONV
    235 _gss_spnego_indicate_mechtypelist (OM_uint32 *minor_status,
    236 				   gss_name_t target_name,
    237 				   OM_uint32 (*func)(gss_name_t, gss_OID),
    238 				   int includeMSCompatOID,
    239 				   gss_const_cred_id_t cred_handle,
    240 				   MechTypeList *mechtypelist,
    241 				   gss_OID *preferred_mech)
    242 {
    243     gss_OID_set supported_mechs = GSS_C_NO_OID_SET;
    244     gss_OID first_mech = GSS_C_NO_OID;
    245     OM_uint32 ret;
    246     size_t i;
    247 
    248     mechtypelist->len = 0;
    249     mechtypelist->val = NULL;
    250 
    251     if (cred_handle) {
    252 	ret = gss_inquire_cred(minor_status,
    253 			       cred_handle,
    254 			       NULL,
    255 			       NULL,
    256 			       NULL,
    257 			       &supported_mechs);
    258     } else {
    259 	ret = gss_indicate_mechs(minor_status, &supported_mechs);
    260     }
    261 
    262     if (ret != GSS_S_COMPLETE) {
    263 	return ret;
    264     }
    265 
    266     if (supported_mechs->count == 0) {
    267 	*minor_status = ENOENT;
    268 	gss_release_oid_set(minor_status, &supported_mechs);
    269 	return GSS_S_FAILURE;
    270     }
    271 
    272     ret = (*func)(target_name, GSS_KRB5_MECHANISM);
    273     if (ret == GSS_S_COMPLETE) {
    274 	ret = add_mech_type(GSS_KRB5_MECHANISM,
    275 			    includeMSCompatOID,
    276 			    mechtypelist);
    277 	if (!GSS_ERROR(ret))
    278 	    first_mech = GSS_KRB5_MECHANISM;
    279     }
    280     ret = GSS_S_COMPLETE;
    281 
    282     for (i = 0; i < supported_mechs->count; i++) {
    283 	OM_uint32 subret;
    284 	if (gss_oid_equal(&supported_mechs->elements[i], GSS_SPNEGO_MECHANISM))
    285 	    continue;
    286 	if (gss_oid_equal(&supported_mechs->elements[i], GSS_KRB5_MECHANISM))
    287 	    continue;
    288 
    289 	subret = (*func)(target_name, &supported_mechs->elements[i]);
    290 	if (subret != GSS_S_COMPLETE)
    291 	    continue;
    292 
    293 	ret = add_mech_type(&supported_mechs->elements[i],
    294 			    includeMSCompatOID,
    295 			    mechtypelist);
    296 	if (ret != 0) {
    297 	    *minor_status = ret;
    298 	    ret = GSS_S_FAILURE;
    299 	    break;
    300 	}
    301 	if (first_mech == GSS_C_NO_OID)
    302 	    first_mech = &supported_mechs->elements[i];
    303     }
    304 
    305     if (mechtypelist->len == 0) {
    306 	gss_release_oid_set(minor_status, &supported_mechs);
    307 	*minor_status = 0;
    308 	return GSS_S_BAD_MECH;
    309     }
    310 
    311     if (preferred_mech != NULL) {
    312 	ret = gss_duplicate_oid(minor_status, first_mech, preferred_mech);
    313 	if (ret != GSS_S_COMPLETE)
    314 	    free_MechTypeList(mechtypelist);
    315     }
    316     gss_release_oid_set(minor_status, &supported_mechs);
    317 
    318     return ret;
    319 }
    320