lib/gssapi/spnego/compat.c

   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 }