lib/gssapi/krb5/init_sec_context.c

   1 /*
   2  * Copyright (c) 1997 - 2003 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("$Id$");
  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_error_code kret;
 115
 116     memset (&creds, 0, sizeof(creds));
 117     krb5_data_zero (fwd_data);
 118
 119     kret = krb5_cc_get_principal(gssapi_krb5_context, ccache, &creds.client);
 120     if (kret)
 121         goto out;
 122
 123     kret = krb5_build_principal(gssapi_krb5_context,
 124                                 &creds.server,
 125                                 strlen(creds.client->realm),
 126                                 creds.client->realm,
 127                                 KRB5_TGS_NAME,
 128                                 creds.client->realm,
 129                                 NULL);
 130     if (kret)
 131         goto out;
 132
 133     creds.times.endtime = 0;
 134
 135     fwd_flags.i = 0;
 136     fwd_flags.b.forwarded = 1;
 137     fwd_flags.b.forwardable = 1;
 138
 139     if ( /*target_name->name.name_type != KRB5_NT_SRV_HST ||*/
 140         target_name->name.name_string.len < 2)
 141         goto out;
 142
 143     kret = krb5_get_forwarded_creds(gssapi_krb5_context,
 144                                     ac,
 145                                     ccache,
 146                                     fwd_flags.i,
 147                                     target_name->name.name_string.val[1],
 148                                     &creds,
 149                                     fwd_data);
 150
 151  out:
 152     if (kret)
 153         *flags &= ~GSS_C_DELEG_FLAG;
 154     else
 155         *flags |= GSS_C_DELEG_FLAG;
 156
 157     if (creds.client)
 158         krb5_free_principal(gssapi_krb5_context, creds.client);
 159     if (creds.server)
 160         krb5_free_principal(gssapi_krb5_context, creds.server);
 161 }
 162
 163 /*
 164  * first stage of init-sec-context
 165  */
 166
 167 static OM_uint32
 168 init_auth
 169 (OM_uint32 * minor_status,
 170  const gss_cred_id_t initiator_cred_handle,
 171  gss_ctx_id_t * context_handle,
 172  const gss_name_t target_name,
 173  const gss_OID mech_type,
 174  OM_uint32 req_flags,
 175  OM_uint32 time_req,
 176  const gss_channel_bindings_t input_chan_bindings,
 177  const gss_buffer_t input_token,
 178  gss_OID * actual_mech_type,
 179  gss_buffer_t output_token,
 180  OM_uint32 * ret_flags,
 181  OM_uint32 * time_rec
 182     )
 183 {
 184     OM_uint32 ret = GSS_S_FAILURE;
 185     krb5_error_code kret;
 186     krb5_flags ap_options;
 187     krb5_creds this_cred, *cred;
 188     krb5_data outbuf;
 189     krb5_ccache ccache;
 190     u_int32_t flags;
 191     Authenticator *auth;
 192     krb5_data authenticator;
 193     Checksum cksum;
 194     krb5_enctype enctype;
 195     krb5_data fwd_data;
 196
 197     krb5_data_zero(&outbuf);
 198     krb5_data_zero(&fwd_data);
 199
 200     *minor_status = 0;
 201
 202     *context_handle = malloc(sizeof(**context_handle));
 203     if (*context_handle == NULL) {
 204         *minor_status = ENOMEM;
 205         return GSS_S_FAILURE;
 206     }
 207
 208     (*context_handle)->auth_context = NULL;
 209     (*context_handle)->source       = NULL;
 210     (*context_handle)->target       = NULL;
 211     (*context_handle)->flags        = 0;
 212     (*context_handle)->more_flags   = 0;
 213     (*context_handle)->ticket       = NULL;
 214     (*context_handle)->lifetime     = GSS_C_INDEFINITE;
 215
 216     kret = krb5_auth_con_init (gssapi_krb5_context,
 217                                &(*context_handle)->auth_context);
 218     if (kret) {
 219         gssapi_krb5_set_error_string ();
 220         *minor_status = kret;
 221         ret = GSS_S_FAILURE;
 222         goto failure;
 223     }
 224
 225     kret = set_addresses ((*context_handle)->auth_context,
 226                           input_chan_bindings);
 227     if (kret) {
 228         *minor_status = kret;
 229         ret = GSS_S_BAD_BINDINGS;
 230         goto failure;
 231     }
 232
 233     {
 234         int32_t tmp;
 235
 236         krb5_auth_con_getflags(gssapi_krb5_context,
 237                                (*context_handle)->auth_context,
 238                                &tmp);
 239         tmp |= KRB5_AUTH_CONTEXT_DO_SEQUENCE;
 240         krb5_auth_con_setflags(gssapi_krb5_context,
 241                                (*context_handle)->auth_context,
 242                                tmp);
 243     }
 244
 245     if (actual_mech_type)
 246         *actual_mech_type = GSS_KRB5_MECHANISM;
 247
 248     if (initiator_cred_handle == GSS_C_NO_CREDENTIAL) {
 249         kret = krb5_cc_default (gssapi_krb5_context, &ccache);
 250         if (kret) {
 251             gssapi_krb5_set_error_string ();
 252             *minor_status = kret;
 253             ret = GSS_S_FAILURE;
 254             goto failure;
 255         }
 256     } else
 257         ccache = initiator_cred_handle->ccache;
 258
 259     kret = krb5_cc_get_principal (gssapi_krb5_context,
 260                                   ccache,
 261                                   &(*context_handle)->source);
 262     if (kret) {
 263         gssapi_krb5_set_error_string ();
 264         *minor_status = kret;
 265         ret = GSS_S_FAILURE;
 266         goto failure;
 267     }
 268
 269     kret = krb5_copy_principal (gssapi_krb5_context,
 270                                 target_name,
 271                                 &(*context_handle)->target);
 272     if (kret) {
 273         gssapi_krb5_set_error_string ();
 274         *minor_status = kret;
 275         ret = GSS_S_FAILURE;
 276         goto failure;
 277     }
 278
 279     ret = _gss_DES3_get_mic_compat(minor_status, *context_handle);
 280     if (ret)
 281         goto failure;
 282
 283
 284     memset(&this_cred, 0, sizeof(this_cred));
 285     this_cred.client          = (*context_handle)->source;
 286     this_cred.server          = (*context_handle)->target;
 287     if (time_req && time_req != GSS_C_INDEFINITE) {
 288         krb5_timestamp ts;
 289
 290         krb5_timeofday (gssapi_krb5_context, &ts);
 291         this_cred.times.endtime = ts + time_req;
 292     } else
 293         this_cred.times.endtime   = 0;
 294     this_cred.session.keytype = 0;
 295
 296     kret = krb5_get_credentials (gssapi_krb5_context,
 297                                  KRB5_TC_MATCH_KEYTYPE,
 298                                  ccache,
 299                                  &this_cred,
 300                                  &cred);
 301
 302     if (kret) {
 303         gssapi_krb5_set_error_string ();
 304         *minor_status = kret;
 305         ret = GSS_S_FAILURE;
 306         goto failure;
 307     }
 308
 309     (*context_handle)->lifetime = cred->times.endtime;
 310
 311     krb5_auth_con_setkey(gssapi_krb5_context,
 312                          (*context_handle)->auth_context,
 313                          &cred->session);
 314
 315     kret = krb5_auth_con_generatelocalsubkey(gssapi_krb5_context,
 316                                              (*context_handle)->auth_context,
 317                                              &cred->session);
 318     if(kret) {
 319         gssapi_krb5_set_error_string ();
 320         *minor_status = kret;
 321         ret = GSS_S_FAILURE;
 322         goto failure;
 323     }
 324
 325     flags = 0;
 326     ap_options = 0;
 327     if (req_flags & GSS_C_DELEG_FLAG)
 328         do_delegation ((*context_handle)->auth_context,
 329                        ccache, cred, target_name, &fwd_data, &flags);
 330
 331     if (req_flags & GSS_C_MUTUAL_FLAG) {
 332         flags |= GSS_C_MUTUAL_FLAG;
 333         ap_options |= AP_OPTS_MUTUAL_REQUIRED;
 334     }
 335
 336     if (req_flags & GSS_C_REPLAY_FLAG)
 337         ;                               /* XXX */
 338     if (req_flags & GSS_C_SEQUENCE_FLAG)
 339         ;                               /* XXX */
 340     if (req_flags & GSS_C_ANON_FLAG)
 341         ;                               /* XXX */
 342     flags |= GSS_C_CONF_FLAG;
 343     flags |= GSS_C_INTEG_FLAG;
 344     flags |= GSS_C_SEQUENCE_FLAG;
 345     flags |= GSS_C_TRANS_FLAG;
 346
 347     if (ret_flags)
 348         *ret_flags = flags;
 349     (*context_handle)->flags = flags;
 350     (*context_handle)->more_flags |= LOCAL;
 351
 352     ret = gssapi_krb5_create_8003_checksum (minor_status,
 353                                             input_chan_bindings,
 354                                             flags,
 355                                             &fwd_data,
 356                                             &cksum);
 357     krb5_data_free (&fwd_data);
 358     if (ret)
 359         goto failure;
 360
 361 #if 1
 362     enctype = (*context_handle)->auth_context->keyblock->keytype;
 363 #else
 364     if ((*context_handle)->auth_context->enctype)
 365         enctype = (*context_handle)->auth_context->enctype;
 366     else {
 367         kret = krb5_keytype_to_enctype(gssapi_krb5_context,
 368                                        (*context_handle)->auth_context->keyblock->keytype,
 369                                        &enctype);
 370         if (kret)
 371             return kret;
 372     }
 373 #endif
 374
 375     kret = krb5_build_authenticator (gssapi_krb5_context,
 376                                      (*context_handle)->auth_context,
 377                                      enctype,
 378                                      cred,
 379                                      &cksum,
 380                                      &auth,
 381                                      &authenticator,
 382                                      KRB5_KU_AP_REQ_AUTH);
 383
 384     if (kret) {
 385         gssapi_krb5_set_error_string ();
 386         *minor_status = kret;
 387         ret = GSS_S_FAILURE;
 388         goto failure;
 389     }
 390
 391     kret = krb5_build_ap_req (gssapi_krb5_context,
 392                               enctype,
 393                               cred,
 394                               ap_options,
 395                               authenticator,
 396                               &outbuf);
 397
 398     if (kret) {
 399         gssapi_krb5_set_error_string ();
 400         *minor_status = kret;
 401         ret = GSS_S_FAILURE;
 402         goto failure;
 403     }
 404
 405     ret = gssapi_krb5_encapsulate (minor_status, &outbuf, output_token,
 406                                    "\x01\x00");
 407     if (ret)
 408         goto failure;
 409
 410     krb5_data_free (&outbuf);
 411
 412     if (flags & GSS_C_MUTUAL_FLAG) {
 413         return GSS_S_CONTINUE_NEEDED;
 414     } else {
 415         if (time_rec)
 416             *time_rec = (*context_handle)->lifetime;
 417
 418         (*context_handle)->more_flags |= OPEN;
 419         return GSS_S_COMPLETE;
 420     }
 421
 422  failure:
 423     krb5_auth_con_free (gssapi_krb5_context,
 424                         (*context_handle)->auth_context);
 425     if((*context_handle)->source)
 426         krb5_free_principal (gssapi_krb5_context,
 427                              (*context_handle)->source);
 428     if((*context_handle)->target)
 429         krb5_free_principal (gssapi_krb5_context,
 430                              (*context_handle)->target);
 431     free (*context_handle);
 432     krb5_data_free (&outbuf);
 433     *context_handle = GSS_C_NO_CONTEXT;
 434     return ret;
 435 }
 436
 437 static OM_uint32
 438 repl_mutual
 439            (OM_uint32 * minor_status,
 440             const gss_cred_id_t initiator_cred_handle,
 441             gss_ctx_id_t * context_handle,
 442             const gss_name_t target_name,
 443             const gss_OID mech_type,
 444             OM_uint32 req_flags,
 445             OM_uint32 time_req,
 446             const gss_channel_bindings_t input_chan_bindings,
 447             const gss_buffer_t input_token,
 448             gss_OID * actual_mech_type,
 449             gss_buffer_t output_token,
 450             OM_uint32 * ret_flags,
 451             OM_uint32 * time_rec
 452            )
 453 {
 454     OM_uint32 ret;
 455     krb5_error_code kret;
 456     krb5_data indata;
 457     krb5_ap_rep_enc_part *repl;
 458
 459     output_token->length = 0;
 460     output_token->value = NULL;
 461
 462     if (actual_mech_type)
 463         *actual_mech_type = GSS_KRB5_MECHANISM;
 464
 465     ret = gssapi_krb5_decapsulate (minor_status, input_token, &indata,
 466                                    "\x02\x00");
 467     if (ret)
 468                                 /* XXX - Handle AP_ERROR */
 469         return ret;
 470
 471     kret = krb5_rd_rep (gssapi_krb5_context,
 472                         (*context_handle)->auth_context,
 473                         &indata,
 474                         &repl);
 475     if (kret) {
 476         gssapi_krb5_set_error_string ();
 477         *minor_status = kret;
 478         return GSS_S_FAILURE;
 479     }
 480     krb5_free_ap_rep_enc_part (gssapi_krb5_context,
 481                                repl);
 482
 483     (*context_handle)->more_flags |= OPEN;
 484
 485     if (time_rec)
 486         *time_rec = (*context_handle)->lifetime;
 487     if (ret_flags)
 488         *ret_flags = (*context_handle)->flags;
 489
 490     *minor_status = 0;
 491     return GSS_S_COMPLETE;
 492 }
 493
 494 /*
 495  * gss_init_sec_context
 496  */
 497
 498 OM_uint32 gss_init_sec_context
 499            (OM_uint32 * minor_status,
 500             const gss_cred_id_t initiator_cred_handle,
 501             gss_ctx_id_t * context_handle,
 502             const gss_name_t target_name,
 503             const gss_OID mech_type,
 504             OM_uint32 req_flags,
 505             OM_uint32 time_req,
 506             const gss_channel_bindings_t input_chan_bindings,
 507             const gss_buffer_t input_token,
 508             gss_OID * actual_mech_type,
 509             gss_buffer_t output_token,
 510             OM_uint32 * ret_flags,
 511             OM_uint32 * time_rec
 512            )
 513 {
 514     GSSAPI_KRB5_INIT ();
 515
 516     output_token->length = 0;
 517     output_token->value  = NULL;
 518
 519     if (ret_flags)
 520         *ret_flags = 0;
 521     if (time_rec)
 522         *time_rec = 0;
 523
 524     if (target_name == GSS_C_NO_NAME) {
 525         if (actual_mech_type)
 526             *actual_mech_type = GSS_C_NO_OID;
 527         *minor_status = 0;
 528         return GSS_S_BAD_NAME;
 529     }
 530
 531     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0)
 532         return init_auth (minor_status,
 533                           initiator_cred_handle,
 534                           context_handle,
 535                           target_name,
 536                           mech_type,
 537                           req_flags,
 538                           time_req,
 539                           input_chan_bindings,
 540                           input_token,
 541                           actual_mech_type,
 542                           output_token,
 543                           ret_flags,
 544                           time_rec);
 545     else
 546         return repl_mutual(minor_status,
 547                            initiator_cred_handle,
 548                            context_handle,
 549                            target_name,
 550                            mech_type,
 551                            req_flags,
 552                            time_req,
 553                            input_chan_bindings,
 554                            input_token,
 555                            actual_mech_type,
 556                            output_token,
 557                            ret_flags,
 558                            time_rec);
 559 }