crypto/heimdal/lib/gssapi/init_sec_context.c

   1 /*
   2  * Copyright (c) 1997 - 2001 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "gssapi_locl.h"
  35
  36 RCSID("$Id: init_sec_context.c,v 1.27 2001/05/11 09:16:46 assar Exp $");
  37
  38 /*
  39  * copy the addresses from `input_chan_bindings' (if any) to
  40  * the auth context `ac'
  41  */
  42
  43 static OM_uint32
  44 set_addresses (krb5_auth_context ac,
  45                const gss_channel_bindings_t input_chan_bindings)
  46 {
  47     /* Port numbers are expected to be in application_data.value,
  48      * initator's port first */
  49
  50     krb5_address initiator_addr, acceptor_addr;
  51     krb5_error_code kret;
  52
  53     if (input_chan_bindings == GSS_C_NO_CHANNEL_BINDINGS
  54         || input_chan_bindings->application_data.length !=
  55         2 * sizeof(ac->local_port))
  56         return 0;
  57
  58     memset(&initiator_addr, 0, sizeof(initiator_addr));
  59     memset(&acceptor_addr, 0, sizeof(acceptor_addr));
  60
  61     ac->local_port =
  62         *(int16_t *) input_chan_bindings->application_data.value;
  63
  64     ac->remote_port =
  65         *((int16_t *) input_chan_bindings->application_data.value + 1);
  66
  67     kret = gss_address_to_krb5addr(input_chan_bindings->acceptor_addrtype,
  68                                    &input_chan_bindings->acceptor_address,
  69                                    ac->remote_port,
  70                                    &acceptor_addr);
  71     if (kret)
  72         return kret;
  73
  74     kret = gss_address_to_krb5addr(input_chan_bindings->initiator_addrtype,
  75                                    &input_chan_bindings->initiator_address,
  76                                    ac->local_port,
  77                                    &initiator_addr);
  78     if (kret) {
  79         krb5_free_address (gssapi_krb5_context, &acceptor_addr);
  80         return kret;
  81     }
  82
  83     kret = krb5_auth_con_setaddrs(gssapi_krb5_context,
  84                                   ac,
  85                                   &initiator_addr,  /* local address */
  86                                   &acceptor_addr);  /* remote address */
  87
  88     krb5_free_address (gssapi_krb5_context, &initiator_addr);
  89     krb5_free_address (gssapi_krb5_context, &acceptor_addr);
  90
  91 #if 0
  92     free(input_chan_bindings->application_data.value);
  93     input_chan_bindings->application_data.value = NULL;
  94     input_chan_bindings->application_data.length = 0;
  95 #endif
  96
  97     return kret;
  98 }
  99
 100 /*
 101  * handle delegated creds in init-sec-context
 102  */
 103
 104 static void
 105 do_delegation (krb5_auth_context ac,
 106                krb5_ccache ccache,
 107                krb5_creds *cred,
 108                const gss_name_t target_name,
 109                krb5_data *fwd_data,
 110                int *flags)
 111 {
 112     krb5_creds creds;
 113     krb5_kdc_flags fwd_flags;
 114     krb5_keyblock *subkey;
 115     krb5_error_code kret;
 116
 117     memset (&creds, 0, sizeof(creds));
 118     krb5_data_zero (fwd_data);
 119
 120     kret = krb5_generate_subkey (gssapi_krb5_context, &cred->session, &subkey);
 121     if (kret)
 122         goto out;
 123
 124     kret = krb5_auth_con_setlocalsubkey(gssapi_krb5_context, ac, subkey);
 125     krb5_free_keyblock (gssapi_krb5_context, subkey);
 126     if (kret)
 127         goto out;
 128
 129     kret = krb5_cc_get_principal(gssapi_krb5_context, ccache, &creds.client);
 130     if (kret)
 131         goto out;
 132
 133     kret = krb5_build_principal(gssapi_krb5_context,
 134                                 &creds.server,
 135                                 strlen(creds.client->realm),
 136                                 creds.client->realm,
 137                                 KRB5_TGS_NAME,
 138                                 creds.client->realm,
 139                                 NULL);
 140     if (kret)
 141         goto out;
 142
 143     creds.times.endtime = 0;
 144
 145     fwd_flags.i = 0;
 146     fwd_flags.b.forwarded = 1;
 147     fwd_flags.b.forwardable = 1;
 148
 149     if ( /*target_name->name.name_type != KRB5_NT_SRV_HST ||*/
 150         target_name->name.name_string.len < 2)
 151         goto out;
 152
 153     kret = krb5_get_forwarded_creds(gssapi_krb5_context,
 154                                     ac,
 155                                     ccache,
 156                                     fwd_flags.i,
 157                                     target_name->name.name_string.val[1],
 158                                     &creds,
 159                                     fwd_data);
 160
 161  out:
 162     if (kret)
 163         *flags &= ~GSS_C_DELEG_FLAG;
 164     else
 165         *flags |= GSS_C_DELEG_FLAG;
 166
 167     if (creds.client)
 168         krb5_free_principal(gssapi_krb5_context, creds.client);
 169     if (creds.server)
 170         krb5_free_principal(gssapi_krb5_context, creds.server);
 171 }
 172
 173 /*
 174  * first stage of init-sec-context
 175  */
 176
 177 static OM_uint32
 178 init_auth
 179 (OM_uint32 * minor_status,
 180  const gss_cred_id_t initiator_cred_handle,
 181  gss_ctx_id_t * context_handle,
 182  const gss_name_t target_name,
 183  const gss_OID mech_type,
 184  OM_uint32 req_flags,
 185  OM_uint32 time_req,
 186  const gss_channel_bindings_t input_chan_bindings,
 187  const gss_buffer_t input_token,
 188  gss_OID * actual_mech_type,
 189  gss_buffer_t output_token,
 190  OM_uint32 * ret_flags,
 191  OM_uint32 * time_rec
 192     )
 193 {
 194     OM_uint32 ret = GSS_S_FAILURE;
 195     krb5_error_code kret;
 196     krb5_flags ap_options;
 197     krb5_creds this_cred, *cred;
 198     krb5_data outbuf;
 199     krb5_ccache ccache;
 200     u_int32_t flags;
 201     Authenticator *auth;
 202     krb5_data authenticator;
 203     Checksum cksum;
 204     krb5_enctype enctype;
 205     krb5_data fwd_data;
 206
 207     output_token->length = 0;
 208     output_token->value  = NULL;
 209
 210     krb5_data_zero(&outbuf);
 211     krb5_data_zero(&fwd_data);
 212
 213     *minor_status = 0;
 214
 215     *context_handle = malloc(sizeof(**context_handle));
 216     if (*context_handle == NULL) {
 217         *minor_status = ENOMEM;
 218         return GSS_S_FAILURE;
 219     }
 220
 221     (*context_handle)->auth_context = NULL;
 222     (*context_handle)->source       = NULL;
 223     (*context_handle)->target       = NULL;
 224     (*context_handle)->flags        = 0;
 225     (*context_handle)->more_flags   = 0;
 226     (*context_handle)->ticket       = NULL;
 227
 228     kret = krb5_auth_con_init (gssapi_krb5_context,
 229                                &(*context_handle)->auth_context);
 230     if (kret) {
 231         gssapi_krb5_set_error_string ();
 232         *minor_status = kret;
 233         ret = GSS_S_FAILURE;
 234         goto failure;
 235     }
 236
 237     kret = set_addresses ((*context_handle)->auth_context,
 238                           input_chan_bindings);
 239     if (kret) {
 240         *minor_status = kret;
 241         ret = GSS_S_BAD_BINDINGS;
 242         goto failure;
 243     }
 244
 245     {
 246         int32_t tmp;
 247
 248         krb5_auth_con_getflags(gssapi_krb5_context,
 249                                (*context_handle)->auth_context,
 250                                &tmp);
 251         tmp |= KRB5_AUTH_CONTEXT_DO_SEQUENCE;
 252         krb5_auth_con_setflags(gssapi_krb5_context,
 253                                (*context_handle)->auth_context,
 254                                tmp);
 255     }
 256
 257     if (actual_mech_type)
 258         *actual_mech_type = GSS_KRB5_MECHANISM;
 259
 260     if (initiator_cred_handle == GSS_C_NO_CREDENTIAL) {
 261         kret = krb5_cc_default (gssapi_krb5_context, &ccache);
 262         if (kret) {
 263             gssapi_krb5_set_error_string ();
 264             *minor_status = kret;
 265             ret = GSS_S_FAILURE;
 266             goto failure;
 267         }
 268     } else
 269         ccache = initiator_cred_handle->ccache;
 270
 271     kret = krb5_cc_get_principal (gssapi_krb5_context,
 272                                   ccache,
 273                                   &(*context_handle)->source);
 274     if (kret) {
 275         gssapi_krb5_set_error_string ();
 276         *minor_status = kret;
 277         ret = GSS_S_FAILURE;
 278         goto failure;
 279     }
 280
 281     kret = krb5_copy_principal (gssapi_krb5_context,
 282                                 target_name,
 283                                 &(*context_handle)->target);
 284     if (kret) {
 285         gssapi_krb5_set_error_string ();
 286         *minor_status = kret;
 287         ret = GSS_S_FAILURE;
 288         goto failure;
 289     }
 290
 291     memset(&this_cred, 0, sizeof(this_cred));
 292     this_cred.client          = (*context_handle)->source;
 293     this_cred.server          = (*context_handle)->target;
 294     if (time_req) {
 295         krb5_timestamp ts;
 296
 297         krb5_timeofday (gssapi_krb5_context, &ts);
 298         this_cred.times.endtime = ts + time_req;
 299     } else
 300         this_cred.times.endtime   = 0;
 301     this_cred.session.keytype = 0;
 302
 303     kret = krb5_get_credentials (gssapi_krb5_context,
 304                                  KRB5_TC_MATCH_KEYTYPE,
 305                                  ccache,
 306                                  &this_cred,
 307                                  &cred);
 308
 309     if (kret) {
 310         gssapi_krb5_set_error_string ();
 311         *minor_status = kret;
 312         ret = GSS_S_FAILURE;
 313         goto failure;
 314     }
 315
 316     krb5_auth_con_setkey(gssapi_krb5_context,
 317                          (*context_handle)->auth_context,
 318                          &cred->session);
 319
 320     flags = 0;
 321     ap_options = 0;
 322     if (req_flags & GSS_C_DELEG_FLAG)
 323         do_delegation ((*context_handle)->auth_context,
 324                        ccache, cred, target_name, &fwd_data, &flags);
 325
 326     if (req_flags & GSS_C_MUTUAL_FLAG) {
 327         flags |= GSS_C_MUTUAL_FLAG;
 328         ap_options |= AP_OPTS_MUTUAL_REQUIRED;
 329     }
 330
 331     if (req_flags & GSS_C_REPLAY_FLAG)
 332         ;                               /* XXX */
 333     if (req_flags & GSS_C_SEQUENCE_FLAG)
 334         ;                               /* XXX */
 335     if (req_flags & GSS_C_ANON_FLAG)
 336         ;                               /* XXX */
 337     flags |= GSS_C_CONF_FLAG;
 338     flags |= GSS_C_INTEG_FLAG;
 339     flags |= GSS_C_SEQUENCE_FLAG;
 340     flags |= GSS_C_TRANS_FLAG;
 341
 342     if (ret_flags)
 343         *ret_flags = flags;
 344     (*context_handle)->flags = flags;
 345     (*context_handle)->more_flags = LOCAL;
 346
 347     kret = gssapi_krb5_create_8003_checksum (input_chan_bindings,
 348                                              flags,
 349                                              &fwd_data,
 350                                              &cksum);
 351     krb5_data_free (&fwd_data);
 352     if (kret) {
 353         gssapi_krb5_set_error_string ();
 354         *minor_status = kret;
 355         ret = GSS_S_FAILURE;
 356         goto failure;
 357     }
 358
 359 #if 1
 360     enctype = (*context_handle)->auth_context->keyblock->keytype;
 361 #else
 362     if ((*context_handle)->auth_context->enctype)
 363         enctype = (*context_handle)->auth_context->enctype;
 364     else {
 365         kret = krb5_keytype_to_enctype(gssapi_krb5_context,
 366                                        (*context_handle)->auth_context->keyblock->keytype,
 367                                        &enctype);
 368         if (kret)
 369             return kret;
 370     }
 371 #endif
 372
 373     kret = krb5_build_authenticator (gssapi_krb5_context,
 374                                      (*context_handle)->auth_context,
 375                                      enctype,
 376                                      cred,
 377                                      &cksum,
 378                                      &auth,
 379                                      &authenticator,
 380                                      KRB5_KU_AP_REQ_AUTH);
 381
 382     if (kret) {
 383         gssapi_krb5_set_error_string ();
 384         *minor_status = kret;
 385         ret = GSS_S_FAILURE;
 386         goto failure;
 387     }
 388
 389     kret = krb5_build_ap_req (gssapi_krb5_context,
 390                               enctype,
 391                               cred,
 392                               ap_options,
 393                               authenticator,
 394                               &outbuf);
 395
 396     if (kret) {
 397         gssapi_krb5_set_error_string ();
 398         *minor_status = kret;
 399         ret = GSS_S_FAILURE;
 400         goto failure;
 401     }
 402
 403     ret = gssapi_krb5_encapsulate (&outbuf, output_token, "\x01\x00");
 404     if (ret) {
 405         *minor_status = kret;
 406         goto failure;
 407     }
 408
 409     krb5_data_free (&outbuf);
 410
 411     if (flags & GSS_C_MUTUAL_FLAG) {
 412         return GSS_S_CONTINUE_NEEDED;
 413     } else {
 414         (*context_handle)->more_flags |= OPEN;
 415         return GSS_S_COMPLETE;
 416     }
 417
 418  failure:
 419     krb5_auth_con_free (gssapi_krb5_context,
 420                         (*context_handle)->auth_context);
 421     if((*context_handle)->source)
 422         krb5_free_principal (gssapi_krb5_context,
 423                              (*context_handle)->source);
 424     if((*context_handle)->target)
 425         krb5_free_principal (gssapi_krb5_context,
 426                              (*context_handle)->target);
 427     free (*context_handle);
 428     krb5_data_free (&outbuf);
 429     *context_handle = GSS_C_NO_CONTEXT;
 430     return ret;
 431 }
 432
 433 static OM_uint32
 434 repl_mutual
 435            (OM_uint32 * minor_status,
 436             const gss_cred_id_t initiator_cred_handle,
 437             gss_ctx_id_t * context_handle,
 438             const gss_name_t target_name,
 439             const gss_OID mech_type,
 440             OM_uint32 req_flags,
 441             OM_uint32 time_req,
 442             const gss_channel_bindings_t input_chan_bindings,
 443             const gss_buffer_t input_token,
 444             gss_OID * actual_mech_type,
 445             gss_buffer_t output_token,
 446             OM_uint32 * ret_flags,
 447             OM_uint32 * time_rec
 448            )
 449 {
 450     OM_uint32 ret;
 451     krb5_error_code kret;
 452     krb5_data indata;
 453     krb5_ap_rep_enc_part *repl;
 454
 455     ret = gssapi_krb5_decapsulate (input_token, &indata, "\x02\x00");
 456     if (ret) {
 457                                 /* XXX - Handle AP_ERROR */
 458         *minor_status = 0;
 459         return GSS_S_FAILURE;
 460     }
 461
 462     kret = krb5_rd_rep (gssapi_krb5_context,
 463                         (*context_handle)->auth_context,
 464                         &indata,
 465                         &repl);
 466     if (kret) {
 467         gssapi_krb5_set_error_string ();
 468         *minor_status = kret;
 469         return GSS_S_FAILURE;
 470     }
 471     krb5_free_ap_rep_enc_part (gssapi_krb5_context,
 472                                repl);
 473
 474     output_token->length = 0;
 475
 476     (*context_handle)->more_flags |= OPEN;
 477
 478     return GSS_S_COMPLETE;
 479 }
 480
 481 /*
 482  * gss_init_sec_context
 483  */
 484
 485 OM_uint32 gss_init_sec_context
 486            (OM_uint32 * minor_status,
 487             const gss_cred_id_t initiator_cred_handle,
 488             gss_ctx_id_t * context_handle,
 489             const gss_name_t target_name,
 490             const gss_OID mech_type,
 491             OM_uint32 req_flags,
 492             OM_uint32 time_req,
 493             const gss_channel_bindings_t input_chan_bindings,
 494             const gss_buffer_t input_token,
 495             gss_OID * actual_mech_type,
 496             gss_buffer_t output_token,
 497             OM_uint32 * ret_flags,
 498             OM_uint32 * time_rec
 499            )
 500 {
 501     gssapi_krb5_init ();
 502
 503     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0)
 504         return init_auth (minor_status,
 505                           initiator_cred_handle,
 506                           context_handle,
 507                           target_name,
 508                           mech_type,
 509                           req_flags,
 510                           time_req,
 511                           input_chan_bindings,
 512                           input_token,
 513                           actual_mech_type,
 514                           output_token,
 515                           ret_flags,
 516                           time_rec);
 517     else
 518         return repl_mutual(minor_status,
 519                            initiator_cred_handle,
 520                            context_handle,
 521                            target_name,
 522                            mech_type,
 523                            req_flags,
 524                            time_req,
 525                            input_chan_bindings,
 526                            input_token,
 527                            actual_mech_type,
 528                            output_token,
 529                            ret_flags,
 530                            time_rec);
 531 }