plugins/gs2.c

   1 /*
   2  * Copyright (c) 2010 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. Redistributions in any form must be accompanied by information on
  17  *    how to obtain complete source code for the GS2 software and any
  18  *    accompanying software that uses the GS2 software. The source code
  19  *    must either be included in the distribution or be available for no
  20  *    more than the cost of distribution plus a nominal fee, and must be
  21  *    freely redistributable under reasonable conditions. For an
  22  *    executable file, complete source code means the source code for all
  23  *    modules it contains. It does not include source code for modules or
  24  *    files that typically accompany the major components of the operating
  25  *    system on which the executable file runs.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE ``AS IS'' AND ANY EXPRESS
  28  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  29  * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR
  30  * NON-INFRINGEMENT, ARE DISCLAIMED. IN NO EVENT SHALL PADL SOFTWARE
  31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  37  * THE POSSIBILITY OF SUCH DAMAGE.
  38  */
  39 /*
  40  * Copyright (c) 1998-2003 Carnegie Mellon University.
  41  * All rights reserved.
  42  *
  43  * Redistribution and use in source and binary forms, with or without
  44  * modification, are permitted provided that the following conditions
  45  * are met:
  46  *
  47  * 1. Redistributions of source code must retain the above copyright
  48  *    notice, this list of conditions and the following disclaimer.
  49  *
  50  * 2. Redistributions in binary form must reproduce the above copyright
  51  *    notice, this list of conditions and the following disclaimer in
  52  *    the documentation and/or other materials provided with the
  53  *    distribution.
  54  *
  55  * 3. The name "Carnegie Mellon University" must not be used to
  56  *    endorse or promote products derived from this software without
  57  *    prior written permission. For permission or any other legal
  58  *    details, please contact
  59  *      Office of Technology Transfer
  60  *      Carnegie Mellon University
  61  *      5000 Forbes Avenue
  62  *      Pittsburgh, PA  15213-3890
  63  *      (412) 268-4387, fax: (412) 268-7395
  64  *      tech-transfer@andrew.cmu.edu
  65  *
  66  * 4. Redistributions of any form whatsoever must retain the following
  67  *    acknowledgment:
  68  *    "This product includes software developed by Computing Services
  69  *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
  70  *
  71  * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
  72  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  73  * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
  74  * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  75  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
  76  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  77  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  78  */
  79
  80 #include <config.h>
  81 #include <gssapi/gssapi.h>
  82 #include <gssapi/gssapi_ext.h>
  83 #include <fcntl.h>
  84 #include <stdio.h>
  85 #include <sasl.h>
  86 #include <saslutil.h>
  87 #include <saslplug.h>
  88
  89 #include "plugin_common.h"
  90
  91 #ifdef HAVE_UNISTD_H
  92 #include <unistd.h>
  93 #endif
  94
  95 #include <errno.h>
  96 #include <assert.h>
  97 #include "gs2_token.h"
  98
  99 #define GS2_CB_FLAG_MASK    0x0F
 100 #define GS2_CB_FLAG_N       0x00
 101 #define GS2_CB_FLAG_P       0x01
 102 #define GS2_CB_FLAG_Y       0x02
 103 #define GS2_NONSTD_FLAG     0x10
 104
 105 typedef struct context {
 106     gss_ctx_id_t gss_ctx;
 107     gss_name_t client_name;
 108     gss_name_t server_name;
 109     gss_cred_id_t server_creds;
 110     gss_cred_id_t client_creds;
 111     char *out_buf;
 112     unsigned out_buf_len;
 113     const sasl_utils_t *utils;
 114     char *authid;
 115     char *authzid;
 116     union {
 117         sasl_client_plug_t *client;
 118         sasl_server_plug_t *server;
 119     } plug;
 120     gss_OID mechanism;
 121     int gs2_flags;
 122     char *cbindingname;
 123     struct gss_channel_bindings_struct gss_cbindings;
 124     sasl_secret_t *password;
 125     unsigned int free_password;
 126     OM_uint32 lifetime;
 127 } context_t;
 128
 129 static gss_OID_set gs2_mechs = GSS_C_NO_OID_SET;
 130
 131 static int gs2_get_init_creds(context_t *context,
 132                               sasl_client_params_t *params,
 133                               sasl_interact_t **prompt_need,
 134                               sasl_out_params_t *oparams);
 135
 136 static int gs2_verify_initial_message(context_t *text,
 137                                       sasl_server_params_t *sparams,
 138                                       const char *in,
 139                                       unsigned inlen,
 140                                       gss_buffer_t token);
 141
 142 static int gs2_make_header(context_t *text,
 143                            sasl_client_params_t *cparams,
 144                            const char *authzid,
 145                            char **out,
 146                            unsigned *outlen);
 147
 148 static int gs2_make_message(context_t *text,
 149                             sasl_client_params_t *cparams,
 150                             int initialContextToken,
 151                             gss_buffer_t token,
 152                             char **out,
 153                             unsigned *outlen);
 154
 155 static int gs2_get_mech_attrs(const sasl_utils_t *utils,
 156                               const gss_OID mech,
 157                               unsigned int *security_flags,
 158                               unsigned int *features,
 159                               const unsigned long **prompts);
 160
 161 static int gs2_indicate_mechs(const sasl_utils_t *utils);
 162
 163 static int gs2_map_sasl_name(const sasl_utils_t *utils,
 164                              const char *mech,
 165                              gss_OID *oid);
 166
 167 static int gs2_duplicate_buffer(const sasl_utils_t *utils,
 168                                 const gss_buffer_t src,
 169                                 gss_buffer_t dst);
 170
 171 static int gs2_unescape_authzid(const sasl_utils_t *utils,
 172                                 char **in,
 173                                 unsigned *inlen,
 174                                 char **authzid);
 175
 176 static int gs2_escape_authzid(const sasl_utils_t *utils,
 177                               const char *in,
 178                               unsigned inlen,
 179                               char **authzid);
 180
 181 /* sasl_gs_log: only logs status string returned from gss_display_status() */
 182 #define sasl_gs2_log(x,y,z) sasl_gs2_seterror_(x,y,z,1)
 183 #define sasl_gs2_seterror(x,y,z) sasl_gs2_seterror_(x,y,z,0)
 184
 185 static int
 186 sasl_gs2_seterror_(const sasl_utils_t *utils, OM_uint32 maj, OM_uint32 min,
 187                    int logonly);
 188
 189 static context_t *
 190 sasl_gs2_new_context(const sasl_utils_t *utils)
 191 {
 192     context_t *ret;
 193
 194     ret = utils->malloc(sizeof(context_t));
 195     if (!ret)
 196         return NULL;
 197
 198     memset(ret, 0, sizeof(context_t));
 199     ret->utils = utils;
 200
 201     return ret;
 202 }
 203
 204 static int
 205 sasl_gs2_free_context_contents(context_t *text)
 206 {
 207     OM_uint32 min_stat;
 208
 209     if (text == NULL)
 210         return SASL_OK;
 211
 212     if (text->gss_ctx != GSS_C_NO_CONTEXT) {
 213         gss_delete_sec_context(&min_stat,&text->gss_ctx,
 214                                GSS_C_NO_BUFFER);
 215         text->gss_ctx = GSS_C_NO_CONTEXT;
 216     }
 217
 218     if (text->client_name != GSS_C_NO_NAME) {
 219         gss_release_name(&min_stat,&text->client_name);
 220         text->client_name = GSS_C_NO_NAME;
 221     }
 222
 223     if (text->server_name != GSS_C_NO_NAME) {
 224         gss_release_name(&min_stat,&text->server_name);
 225         text->server_name = GSS_C_NO_NAME;
 226     }
 227
 228     if (text->server_creds != GSS_C_NO_CREDENTIAL) {
 229         gss_release_cred(&min_stat, &text->server_creds);
 230         text->server_creds = GSS_C_NO_CREDENTIAL;
 231     }
 232
 233     if (text->client_creds != GSS_C_NO_CREDENTIAL) {
 234         gss_release_cred(&min_stat, &text->client_creds);
 235         text->client_creds = GSS_C_NO_CREDENTIAL;
 236     }
 237
 238     if (text->authid != NULL) {
 239         text->utils->free(text->authid);
 240         text->authid = NULL;
 241     }
 242
 243     if (text->authzid != NULL) {
 244         text->utils->free(text->authzid);
 245         text->authzid = NULL;
 246     }
 247
 248     gss_release_buffer(&min_stat, &text->gss_cbindings.application_data);
 249
 250     if (text->out_buf != NULL) {
 251         text->utils->free(text->out_buf);
 252         text->out_buf = NULL;
 253     }
 254
 255     text->out_buf_len = 0;
 256
 257     if (text->cbindingname != NULL) {
 258         text->utils->free(text->cbindingname);
 259         text->cbindingname = NULL;
 260     }
 261
 262     if (text->free_password)
 263         _plug_free_secret(text->utils, &text->password);
 264
 265     memset(text, 0, sizeof(*text));
 266
 267     return SASL_OK;
 268 }
 269
 270 static void
 271 gs2_common_mech_dispose(void *conn_context, const sasl_utils_t *utils)
 272 {
 273     sasl_gs2_free_context_contents((context_t *)(conn_context));
 274     utils->free(conn_context);
 275 }
 276
 277 static void
 278 gs2_common_mech_free(void *global_context __attribute__((unused)),
 279                      const sasl_utils_t *utils)
 280 {
 281     OM_uint32 minor;
 282
 283     if (gs2_mechs != GSS_C_NO_OID_SET) {
 284         gss_release_oid_set(&minor, &gs2_mechs);
 285         gs2_mechs = GSS_C_NO_OID_SET;
 286     }
 287 }
 288
 289 /*****************************  Server Section  *****************************/
 290
 291 static int
 292 gs2_server_mech_new(void *glob_context,
 293                     sasl_server_params_t *params,
 294                     const char *challenge __attribute__((unused)),
 295                     unsigned challen __attribute__((unused)),
 296                     void **conn_context)
 297 {
 298     context_t *text;
 299     int ret;
 300
 301     text = sasl_gs2_new_context(params->utils);
 302     if (text == NULL) {
 303         MEMERROR(params->utils);
 304         return SASL_NOMEM;
 305     }
 306
 307     text->gss_ctx = GSS_C_NO_CONTEXT;
 308     text->client_name = GSS_C_NO_NAME;
 309     text->server_name = GSS_C_NO_NAME;
 310     text->server_creds = GSS_C_NO_CREDENTIAL;
 311     text->client_creds = GSS_C_NO_CREDENTIAL;
 312     text->plug.server = glob_context;
 313
 314     ret = gs2_map_sasl_name(params->utils, text->plug.server->mech_name,
 315                             &text->mechanism);
 316     if (ret != SASL_OK) {
 317         gs2_common_mech_dispose(text, params->utils);
 318         return ret;
 319     }
 320
 321     *conn_context = text;
 322
 323     return SASL_OK;
 324 }
 325
 326 static int
 327 gs2_server_mech_step(void *conn_context,
 328                      sasl_server_params_t *params,
 329                      const char *clientin,
 330                      unsigned clientinlen,
 331                      const char **serverout,
 332                      unsigned *serveroutlen,
 333                      sasl_out_params_t *oparams)
 334 {
 335     context_t *text = (context_t *)conn_context;
 336     gss_buffer_desc input_token = GSS_C_EMPTY_BUFFER;
 337     gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER;
 338     OM_uint32 maj_stat = GSS_S_FAILURE, min_stat = 0;
 339     gss_buffer_desc name_buf = GSS_C_EMPTY_BUFFER;
 340     gss_buffer_desc short_name_buf = GSS_C_EMPTY_BUFFER;
 341     gss_name_t without = GSS_C_NO_NAME;
 342     gss_OID_set_desc mechs;
 343     OM_uint32 out_flags = 0;
 344     int ret = 0, equal = 0;
 345     int initialContextToken = (text->gss_ctx == GSS_C_NO_CONTEXT);
 346     char *p;
 347
 348     if (serverout == NULL) {
 349         PARAMERROR(text->utils);
 350         return SASL_BADPARAM;
 351     }
 352
 353     *serverout = NULL;
 354     *serveroutlen = 0;
 355
 356     if (initialContextToken) {
 357         name_buf.length = strlen(params->service) + 1 + strlen(params->serverFQDN);
 358         name_buf.value = params->utils->malloc(name_buf.length + 1);
 359         if (name_buf.value == NULL) {
 360             MEMERROR(text->utils);
 361             ret = SASL_NOMEM;
 362             goto cleanup;
 363         }
 364         snprintf(name_buf.value, name_buf.length + 1,
 365                  "%s@%s", params->service, params->serverFQDN);
 366         maj_stat = gss_import_name(&min_stat,
 367                                    &name_buf,
 368                                    GSS_C_NT_HOSTBASED_SERVICE,
 369                                    &text->server_name);
 370         params->utils->free(name_buf.value);
 371         name_buf.value = NULL;
 372
 373         if (GSS_ERROR(maj_stat))
 374             goto cleanup;
 375
 376         assert(text->server_creds == GSS_C_NO_CREDENTIAL);
 377
 378         mechs.count = 1;
 379         mechs.elements = (gss_OID)text->mechanism;
 380
 381         if (params->gss_creds == GSS_C_NO_CREDENTIAL) {
 382             maj_stat = gss_acquire_cred(&min_stat,
 383                                         text->server_name,
 384                                         GSS_C_INDEFINITE,
 385                                         &mechs,
 386                                         GSS_C_ACCEPT,
 387                                         &text->server_creds,
 388                                         NULL,
 389                                         &text->lifetime);
 390             if (GSS_ERROR(maj_stat))
 391                 goto cleanup;
 392         }
 393
 394         ret = gs2_verify_initial_message(text,
 395                                          params,
 396                                          clientin,
 397                                          clientinlen,
 398                                          &input_token);
 399         if (ret != SASL_OK)
 400             goto cleanup;
 401     } else {
 402         input_token.value = (void *)clientin;
 403         input_token.length = clientinlen;
 404     }
 405
 406     maj_stat = gss_accept_sec_context(&min_stat,
 407                                       &text->gss_ctx,
 408                                       (params->gss_creds != GSS_C_NO_CREDENTIAL)
 409                                         ? (gss_cred_id_t)params->gss_creds
 410                                         : text->server_creds,
 411                                       &input_token,
 412                                       &text->gss_cbindings,
 413                                       &text->client_name,
 414                                       NULL,
 415                                       &output_token,
 416                                       &out_flags,
 417                                       &text->lifetime,
 418                                       &text->client_creds);
 419     if (GSS_ERROR(maj_stat)) {
 420         sasl_gs2_log(text->utils, maj_stat, min_stat);
 421         text->utils->seterror(text->utils->conn, SASL_NOLOG,
 422                               "GS2 Failure: gss_accept_sec_context");
 423         ret = (maj_stat == GSS_S_BAD_BINDINGS) ? SASL_BADBINDING : SASL_BADAUTH;
 424         goto cleanup;
 425     }
 426
 427     *serveroutlen = output_token.length;
 428     if (output_token.value != NULL) {
 429         ret = _plug_buf_alloc(text->utils, &text->out_buf,
 430                               &text->out_buf_len, *serveroutlen);
 431         if (ret != SASL_OK)
 432             goto cleanup;
 433         memcpy(text->out_buf, output_token.value, *serveroutlen);
 434         *serverout = text->out_buf;
 435     } else {
 436         /* No output token, send an empty string */
 437         *serverout = "";
 438         serveroutlen = 0;
 439     }
 440
 441     if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 442         ret = SASL_CONTINUE;
 443         goto cleanup;
 444     }
 445
 446     assert(maj_stat == GSS_S_COMPLETE);
 447
 448     if ((out_flags & GSS_C_SEQUENCE_FLAG) == 0)  {
 449         ret = SASL_BADAUTH;
 450         goto cleanup;
 451     }
 452
 453     maj_stat = gss_display_name(&min_stat, text->client_name,
 454                                 &name_buf, NULL);
 455     if (GSS_ERROR(maj_stat))
 456         goto cleanup;
 457
 458     ret = gs2_duplicate_buffer(params->utils, &name_buf, &short_name_buf);
 459     if (ret != 0)
 460         goto cleanup;
 461
 462     p = (char *)memchr(name_buf.value, '@', name_buf.length);
 463     if (p != NULL) {
 464         short_name_buf.length = (p - (char *)name_buf.value);
 465
 466         maj_stat = gss_import_name(&min_stat,
 467                                    &short_name_buf,
 468                                    GSS_C_NT_USER_NAME,
 469                                    &without);
 470         if (GSS_ERROR(maj_stat)) {
 471             ret = SASL_FAIL;
 472             goto cleanup;
 473         }
 474
 475         maj_stat = gss_compare_name(&min_stat, text->client_name,
 476                                     without, &equal);
 477         if (GSS_ERROR(maj_stat)) {
 478             ret = SASL_FAIL;
 479             goto cleanup;
 480         }
 481
 482         if (equal)
 483             ((char *)short_name_buf.value)[short_name_buf.length] = '\0';
 484     }
 485
 486     text->authid = (char *)short_name_buf.value;
 487     short_name_buf.value = NULL;
 488     short_name_buf.length = 0;
 489
 490     if (text->authzid != NULL) {
 491         ret = params->canon_user(params->utils->conn,
 492                                  text->authzid, 0,
 493                                  SASL_CU_AUTHZID, oparams);
 494         if (ret != SASL_OK)
 495             goto cleanup;
 496     }
 497
 498     ret = params->canon_user(params->utils->conn,
 499                              text->authid, 0,
 500                              text->authzid == NULL
 501                                 ? (SASL_CU_AUTHZID | SASL_CU_AUTHID)
 502                                 : SASL_CU_AUTHID,
 503                              oparams);
 504     if (ret != SASL_OK)
 505         goto cleanup;
 506
 507     switch (text->gs2_flags & GS2_CB_FLAG_MASK) {
 508     case GS2_CB_FLAG_N:
 509         oparams->cbindingdisp = SASL_CB_DISP_NONE;
 510         break;
 511     case GS2_CB_FLAG_P:
 512         oparams->cbindingdisp = SASL_CB_DISP_USED;
 513         oparams->cbindingname = text->cbindingname;
 514         break;
 515     case GS2_CB_FLAG_Y:
 516         oparams->cbindingdisp = SASL_CB_DISP_WANT;
 517         break;
 518     }
 519
 520     if (text->client_creds != GSS_C_NO_CREDENTIAL)
 521         oparams->client_creds = &text->client_creds;
 522     else
 523         oparams->client_creds = NULL;
 524
 525     oparams->gss_peer_name = text->client_name;
 526     oparams->gss_local_name = text->server_name;
 527     oparams->maxoutbuf = 0xFFFFFF;
 528     oparams->encode = NULL;
 529     oparams->decode = NULL;
 530     oparams->mech_ssf = 0;
 531     oparams->doneflag = 1;
 532
 533     ret = SASL_OK;
 534
 535 cleanup:
 536     if (initialContextToken)
 537         gss_release_buffer(&min_stat, &input_token);
 538     gss_release_buffer(&min_stat, &name_buf);
 539     gss_release_buffer(&min_stat, &short_name_buf);
 540     gss_release_buffer(&min_stat, &output_token);
 541     gss_release_name(&min_stat, &without);
 542
 543     if (ret == SASL_OK && maj_stat != GSS_S_COMPLETE) {
 544         sasl_gs2_seterror(text->utils, maj_stat, min_stat);
 545         ret = SASL_FAIL;
 546     }
 547     if (ret != SASL_OK && ret != SASL_CONTINUE)
 548         sasl_gs2_free_context_contents(text);
 549
 550     return ret;
 551 }
 552
 553 static int
 554 gs2_common_plug_init(const sasl_utils_t *utils,
 555                      size_t plugsize,
 556                      int (*plug_alloc)(const sasl_utils_t *,
 557                                        void *,
 558                                        const gss_buffer_t,
 559                                        const gss_OID),
 560                      void **pluglist,
 561                      int *plugcount)
 562 {
 563     OM_uint32 major, minor;
 564     size_t i, count = 0;
 565     void *plugs = NULL;
 566
 567     *pluglist = NULL;
 568     *plugcount = 0;
 569
 570     if (gs2_indicate_mechs(utils) != SASL_OK) {
 571         return SASL_NOMECH;
 572     }
 573
 574     plugs = utils->malloc(2 * gs2_mechs->count * plugsize);
 575     if (plugs == NULL) {
 576         MEMERROR(utils);
 577         return SASL_NOMEM;
 578     }
 579     memset(plugs, 0, 2 * gs2_mechs->count * plugsize);
 580
 581     for (i = 0; i < gs2_mechs->count; i++) {
 582         gss_buffer_desc sasl_mech_name = GSS_C_EMPTY_BUFFER;
 583
 584         major = gss_inquire_saslname_for_mech(&minor,
 585                                               &gs2_mechs->elements[i],
 586                                               &sasl_mech_name,
 587                                               GSS_C_NO_BUFFER,
 588                                               GSS_C_NO_BUFFER);
 589         if (GSS_ERROR(major))
 590             continue;
 591
 592 #define PLUG_AT(index)      (void *)((unsigned char *)plugs + (count * plugsize))
 593
 594         if (plug_alloc(utils, PLUG_AT(count), &sasl_mech_name,
 595                        &gs2_mechs->elements[i]) == SASL_OK)
 596             count++;
 597
 598         gss_release_buffer(&minor, &sasl_mech_name);
 599     }
 600
 601     if (count == 0) {
 602         utils->free(plugs);
 603         return SASL_NOMECH;
 604     }
 605
 606     *pluglist = plugs;
 607     *plugcount = count;
 608
 609     return SASL_OK;
 610 }
 611
 612 static int
 613 gs2_server_plug_alloc(const sasl_utils_t *utils,
 614                       void *plug,
 615                       gss_buffer_t sasl_name,
 616                       gss_OID mech)
 617 {
 618     int ret;
 619     sasl_server_plug_t *splug = (sasl_server_plug_t *)plug;
 620     gss_buffer_desc buf;
 621
 622     memset(splug, 0, sizeof(*splug));
 623
 624     ret = gs2_get_mech_attrs(utils, mech,
 625                              &splug->security_flags,
 626                              &splug->features,
 627                              NULL);
 628     if (ret != SASL_OK)
 629         return ret;
 630
 631     ret = gs2_duplicate_buffer(utils, sasl_name, &buf);
 632     if (ret != SASL_OK)
 633         return ret;
 634
 635     splug->mech_name = (char *)buf.value;
 636     splug->glob_context = plug;
 637     splug->mech_new = gs2_server_mech_new;
 638     splug->mech_step = gs2_server_mech_step;
 639     splug->mech_dispose = gs2_common_mech_dispose;
 640     splug->mech_free = gs2_common_mech_free;
 641
 642     return SASL_OK;
 643 }
 644
 645 static sasl_server_plug_t *gs2_server_plugins;
 646 static int gs2_server_plugcount;
 647
 648 int
 649 gs2_server_plug_init(const sasl_utils_t *utils,
 650                      int maxversion,
 651                      int *outversion,
 652                      sasl_server_plug_t **pluglist,
 653                      int *plugcount)
 654 {
 655     int ret;
 656
 657     *pluglist = NULL;
 658     *plugcount = 0;
 659
 660     if (maxversion < SASL_SERVER_PLUG_VERSION)
 661         return SASL_BADVERS;
 662
 663     *outversion = SASL_SERVER_PLUG_VERSION;
 664
 665     if (gs2_server_plugins == NULL) {
 666         ret = gs2_common_plug_init(utils,
 667                                    sizeof(sasl_server_plug_t),
 668                                    gs2_server_plug_alloc,
 669                                    (void **)&gs2_server_plugins,
 670                                    &gs2_server_plugcount);
 671         if (ret != SASL_OK)
 672             return ret;
 673     }
 674
 675     *pluglist = gs2_server_plugins;
 676     *plugcount = gs2_server_plugcount;
 677
 678     return SASL_OK;
 679 }
 680
 681 /*****************************  Client Section  *****************************/
 682
 683 static int gs2_client_mech_step(void *conn_context,
 684                                 sasl_client_params_t *params,
 685                                 const char *serverin,
 686                                 unsigned serverinlen,
 687                                 sasl_interact_t **prompt_need,
 688                                 const char **clientout,
 689                                 unsigned *clientoutlen,
 690                                 sasl_out_params_t *oparams)
 691 {
 692     context_t *text = (context_t *)conn_context;
 693     gss_buffer_desc input_token = GSS_C_EMPTY_BUFFER;
 694     gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER;
 695     gss_buffer_desc name_buf = GSS_C_EMPTY_BUFFER;
 696     OM_uint32 maj_stat = GSS_S_FAILURE, min_stat = 0;
 697     OM_uint32 req_flags, ret_flags;
 698     int ret = SASL_FAIL;
 699     int initialContextToken;
 700
 701     *clientout = NULL;
 702     *clientoutlen = 0;
 703
 704     if (text->gss_ctx == GSS_C_NO_CONTEXT) {
 705         ret = gs2_get_init_creds(text, params, prompt_need, oparams);
 706         if (ret != SASL_OK)
 707             goto cleanup;
 708
 709         initialContextToken = 1;
 710     } else
 711         initialContextToken = 0;
 712
 713     if (text->server_name == GSS_C_NO_NAME) { /* only once */
 714         name_buf.length = strlen(params->service) + 1 + strlen(params->serverFQDN);
 715         name_buf.value = params->utils->malloc(name_buf.length + 1);
 716         if (name_buf.value == NULL) {
 717             ret = SASL_NOMEM;
 718             goto cleanup;
 719         }
 720         if (params->serverFQDN == NULL ||
 721             strlen(params->serverFQDN) == 0) {
 722             SETERROR(text->utils, "GS2 Failure: no serverFQDN");
 723             ret = SASL_FAIL;
 724             goto cleanup;
 725         }
 726
 727         snprintf(name_buf.value, name_buf.length + 1,
 728                  "%s@%s", params->service, params->serverFQDN);
 729
 730         maj_stat = gss_import_name (&min_stat,
 731                                     &name_buf,
 732                                     GSS_C_NT_HOSTBASED_SERVICE,
 733                                     &text->server_name);
 734         params->utils->free(name_buf.value);
 735         name_buf.value = NULL;
 736
 737         if (GSS_ERROR(maj_stat))
 738             goto cleanup;
 739     }
 740
 741     /* From GSSAPI plugin: apparently this is for some IMAP bug workaround */
 742     if (serverinlen == 0 && text->gss_ctx != GSS_C_NO_CONTEXT) {
 743         gss_delete_sec_context(&min_stat, &text->gss_ctx, GSS_C_NO_BUFFER);
 744         text->gss_ctx = GSS_C_NO_CONTEXT;
 745     }
 746
 747     input_token.value = (void *)serverin;
 748     input_token.length = serverinlen;
 749
 750     if (initialContextToken) {
 751         if ((text->plug.client->features & SASL_FEAT_GSS_FRAMING) == 0)
 752             text->gs2_flags |= GS2_NONSTD_FLAG;
 753
 754         switch (params->cbindingdisp) {
 755         case SASL_CB_DISP_NONE:
 756             text->gs2_flags |= GS2_CB_FLAG_N;
 757             break;
 758         case SASL_CB_DISP_USED:
 759             text->gs2_flags |= GS2_CB_FLAG_P;
 760             break;
 761         case SASL_CB_DISP_WANT:
 762             text->gs2_flags |= GS2_CB_FLAG_Y;
 763             break;
 764         }
 765
 766         ret = gs2_make_header(text, params,
 767                               strcmp(oparams->user, oparams->authid) ?
 768                                      (char *) oparams->user : NULL,
 769                               &text->out_buf, &text->out_buf_len);
 770         if (ret != 0)
 771             goto cleanup;
 772     }
 773
 774     req_flags = GSS_C_MUTUAL_FLAG | GSS_C_SEQUENCE_FLAG;
 775
 776     maj_stat = gss_init_sec_context(&min_stat,
 777                                     (params->gss_creds != GSS_C_NO_CREDENTIAL)
 778                                         ? (gss_cred_id_t)params->gss_creds
 779                                         : text->client_creds,
 780                                     &text->gss_ctx,
 781                                     text->server_name,
 782                                     (gss_OID)text->mechanism,
 783                                     req_flags,
 784                                     GSS_C_INDEFINITE,
 785                                     &text->gss_cbindings,
 786                                     serverinlen ? &input_token : GSS_C_NO_BUFFER,
 787                                     NULL,
 788                                     &output_token,
 789                                     &ret_flags,
 790                                     &text->lifetime);
 791     if (GSS_ERROR(maj_stat))
 792         goto cleanup;
 793
 794     ret = gs2_make_message(text, params, initialContextToken, &output_token,
 795                            &text->out_buf, &text->out_buf_len);
 796     if (ret != 0)
 797         goto cleanup;
 798
 799     *clientout = text->out_buf;
 800     *clientoutlen = text->out_buf_len;
 801
 802     if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 803         ret = SASL_CONTINUE;
 804         goto cleanup;
 805     }
 806
 807     if (text->client_name != GSS_C_NO_NAME)
 808         gss_release_name(&min_stat, &text->client_name);
 809
 810     maj_stat = gss_inquire_context(&min_stat,
 811                                    text->gss_ctx,
 812                                    &text->client_name,
 813                                    NULL,
 814                                    &text->lifetime,
 815                                    NULL,
 816                                    &ret_flags, /* flags */
 817                                    NULL,
 818                                    NULL);
 819     if (GSS_ERROR(maj_stat))
 820         goto cleanup;
 821
 822     if ((ret_flags & req_flags) != req_flags) {
 823         maj_stat = SASL_BADAUTH;
 824         goto cleanup;
 825     }
 826
 827     maj_stat = gss_display_name(&min_stat,
 828                                 text->client_name,
 829                                 &name_buf,
 830                                 NULL);
 831     if (GSS_ERROR(maj_stat))
 832         goto cleanup;
 833
 834     oparams->gss_peer_name = text->server_name;
 835     oparams->gss_local_name = text->client_name;
 836     oparams->encode = NULL;
 837     oparams->decode = NULL;
 838     oparams->mech_ssf = 0;
 839     oparams->maxoutbuf = 0xFFFFFF;
 840     oparams->doneflag = 1;
 841
 842 cleanup:
 843     gss_release_buffer(&min_stat, &output_token);
 844     gss_release_buffer(&min_stat, &name_buf);
 845
 846     if (ret == SASL_OK && maj_stat != GSS_S_COMPLETE) {
 847         sasl_gs2_seterror(text->utils, maj_stat, min_stat);
 848         ret = SASL_FAIL;
 849     }
 850     if (ret != SASL_OK && ret != SASL_CONTINUE)
 851         sasl_gs2_free_context_contents(text);
 852
 853     return ret;
 854 }
 855
 856 static int gs2_client_mech_new(void *glob_context,
 857                                sasl_client_params_t *params,
 858                                void **conn_context)
 859 {
 860     context_t *text;
 861     int ret;
 862
 863     text = sasl_gs2_new_context(params->utils);
 864     if (text == NULL) {
 865         MEMERROR(params->utils);
 866         return SASL_NOMEM;
 867     }
 868
 869     text->gss_ctx = GSS_C_NO_CONTEXT;
 870     text->client_name = GSS_C_NO_NAME;
 871     text->server_creds = GSS_C_NO_CREDENTIAL;
 872     text->client_creds  = GSS_C_NO_CREDENTIAL;
 873     text->plug.client = glob_context;
 874
 875     ret = gs2_map_sasl_name(params->utils, text->plug.client->mech_name,
 876                             &text->mechanism);
 877     if (ret != SASL_OK) {
 878         gs2_common_mech_dispose(text, params->utils);
 879         return ret;
 880     }
 881
 882     *conn_context = text;
 883
 884     return SASL_OK;
 885 }
 886
 887 static int
 888 gs2_client_plug_alloc(const sasl_utils_t *utils,
 889                       void *plug,
 890                       gss_buffer_t sasl_name,
 891                       gss_OID mech)
 892 {
 893     int ret;
 894     sasl_client_plug_t *cplug = (sasl_client_plug_t *)plug;
 895     gss_buffer_desc buf;
 896
 897     memset(cplug, 0, sizeof(*cplug));
 898
 899     ret = gs2_get_mech_attrs(utils, mech,
 900                              &cplug->security_flags,
 901                              &cplug->features,
 902                              &cplug->required_prompts);
 903     if (ret != SASL_OK)
 904         return ret;
 905
 906     ret = gs2_duplicate_buffer(utils, sasl_name, &buf);
 907     if (ret != SASL_OK)
 908         return ret;
 909
 910     cplug->mech_name = (char *)buf.value;
 911     cplug->features |= SASL_FEAT_NEEDSERVERFQDN;
 912     cplug->glob_context = plug;
 913     cplug->mech_new = gs2_client_mech_new;
 914     cplug->mech_step = gs2_client_mech_step;
 915     cplug->mech_dispose = gs2_common_mech_dispose;
 916     cplug->mech_free = gs2_common_mech_free;
 917
 918     return SASL_OK;
 919 }
 920
 921 static sasl_client_plug_t *gs2_client_plugins;
 922 static int gs2_client_plugcount;
 923
 924 int
 925 gs2_client_plug_init(const sasl_utils_t *utils,
 926                      int maxversion,
 927                      int *outversion,
 928                      sasl_client_plug_t **pluglist,
 929                      int *plugcount)
 930 {
 931     int ret;
 932
 933     *pluglist = NULL;
 934     *plugcount = 0;
 935
 936     if (maxversion < SASL_CLIENT_PLUG_VERSION)
 937         return SASL_BADVERS;
 938
 939     *outversion = SASL_CLIENT_PLUG_VERSION;
 940
 941     if (gs2_client_plugins == NULL) {
 942         ret = gs2_common_plug_init(utils,
 943                                    sizeof(sasl_client_plug_t),
 944                                    gs2_client_plug_alloc,
 945                                    (void **)&gs2_client_plugins,
 946                                    &gs2_client_plugcount);
 947         if (ret != SASL_OK)
 948             return ret;
 949     }
 950
 951     *pluglist = gs2_client_plugins;
 952     *plugcount = gs2_client_plugcount;
 953
 954     return SASL_OK;
 955 }
 956
 957 /*
 958  * Copy header and application channel bindings to GSS channel bindings
 959  * structure in context.
 960  */
 961 static int
 962 gs2_save_cbindings(context_t *text,
 963                    gss_buffer_t header,
 964                    const sasl_channel_binding_t *cbinding)
 965 {
 966     gss_buffer_t gss_cbindings = &text->gss_cbindings.application_data;
 967     size_t len;
 968     unsigned char *p;
 969
 970     assert(gss_cbindings->value == NULL);
 971
 972     /*
 973      * The application-data field MUST be set to the gs2-header, excluding
 974      * the initial [gs2-nonstd-flag ","] part, concatenated with, when a
 975      * gs2-cb-flag of "p" is used, the application's channel binding data.
 976      */
 977     len = header->length;
 978     if (text->gs2_flags & GS2_NONSTD_FLAG) {
 979         assert(len > 2);
 980         len -= 2;
 981     }
 982     if ((text->gs2_flags & GS2_CB_FLAG_MASK) == GS2_CB_FLAG_P &&
 983         cbinding != NULL) {
 984         len += cbinding->len;
 985     }
 986
 987     gss_cbindings->length = len;
 988     gss_cbindings->value = text->utils->malloc(len);
 989     if (gss_cbindings->value == NULL)
 990         return SASL_NOMEM;
 991
 992     p = (unsigned char *)gss_cbindings->value;
 993     if (text->gs2_flags & GS2_NONSTD_FLAG) {
 994         memcpy(p, (unsigned char *)header->value + 2, header->length - 2);
 995         p += header->length - 2;
 996     } else {
 997         memcpy(p, header->value, header->length);
 998         p += header->length;
 999     }
1000
1001     if ((text->gs2_flags & GS2_CB_FLAG_MASK) == GS2_CB_FLAG_P &&
1002         cbinding != NULL) {
1003         memcpy(p, cbinding->data, cbinding->len);
1004     }
1005
1006     return SASL_OK;
1007 }
1008
1009 #define CHECK_REMAIN(n)     do { if (remain < (n)) return SASL_BADPROT; } while (0)
1010
1011 /*
1012  * Verify gs2-header, save authzid and channel bindings to context.
1013  */
1014 static int
1015 gs2_verify_initial_message(context_t *text,
1016                            sasl_server_params_t *sparams,
1017                            const char *in,
1018                            unsigned inlen,
1019                            gss_buffer_t token)
1020 {
1021     char *p = (char *)in;
1022     unsigned remain = inlen;
1023     int ret;
1024     gss_buffer_desc buf = GSS_C_EMPTY_BUFFER;
1025
1026     assert(text->cbindingname == NULL);
1027     assert(text->authzid == NULL);
1028
1029     token->length = 0;
1030     token->value = NULL;
1031
1032     /* minimum header includes CB flag and non-zero GSS token */
1033     CHECK_REMAIN(4); /* [pny],,. */
1034
1035     /* non-standard GSS framing flag */
1036     if (remain > 1 && memcmp(p, "F,", 2) == 0) {
1037         text->gs2_flags |= GS2_NONSTD_FLAG;
1038         remain -= 2;
1039         p += 2;
1040     }
1041
1042     /* SASL channel bindings */
1043     CHECK_REMAIN(1); /* [pny] */
1044     remain--;
1045     switch (*p++) {
1046     case 'p':
1047         CHECK_REMAIN(1); /* = */
1048         remain--;
1049         if (*p++ != '=')
1050             return SASL_BADPROT;
1051
1052         ret = gs2_unescape_authzid(text->utils, &p, &remain, &text->cbindingname);
1053         if (ret != SASL_OK)
1054             return ret;
1055
1056         text->gs2_flags |= GS2_CB_FLAG_P;
1057         break;
1058     case 'n':
1059         text->gs2_flags |= GS2_CB_FLAG_N;
1060         break;
1061     case 'y':
1062         text->gs2_flags |= GS2_CB_FLAG_Y;
1063         break;
1064     }
1065
1066     CHECK_REMAIN(1); /* , */
1067     remain--;
1068     if (*p++ != ',')
1069         return SASL_BADPROT;
1070
1071     /* authorization identity */
1072     if (remain > 1 && memcmp(p, "a=", 2) == 0) {
1073         CHECK_REMAIN(2);
1074         remain -= 2;
1075         p += 2;
1076
1077         ret = gs2_unescape_authzid(text->utils, &p, &remain, &text->authzid);
1078         if (ret != SASL_OK)
1079             return ret;
1080     }
1081
1082     /* end of header */
1083     CHECK_REMAIN(1); /* , */
1084     remain--;
1085     if (*p++ != ',')
1086         return SASL_BADPROT;
1087
1088     buf.length = inlen - remain;
1089     buf.value = (void *)in;
1090
1091     /* stash channel bindings to pass into gss_accept_sec_context() */
1092     ret = gs2_save_cbindings(text, &buf, sparams->cbinding);
1093     if (ret != SASL_OK)
1094         return ret;
1095
1096     buf.length = remain;
1097     buf.value = p;
1098
1099     if (text->gs2_flags & GS2_NONSTD_FLAG) {
1100         token->value = text->utils->malloc(buf.length);
1101         if (token->value == NULL)
1102             return SASL_NOMEM;
1103
1104         token->length = buf.length;
1105         memcpy(token->value, buf.value, buf.length);
1106     } else {
1107         unsigned int token_size;
1108
1109         /* create a properly formed GSS token */
1110         token_size = gs2_token_size(text->mechanism, buf.length);
1111         token->value = text->utils->malloc(token_size);
1112         if (token->value == NULL)
1113             return SASL_NOMEM;
1114
1115         token->length = token_size;
1116
1117         p = (char *)token->value;
1118         gs2_make_token_header(text->mechanism, buf.length,
1119                               (unsigned char **)&p);
1120         memcpy(p, buf.value, buf.length);
1121     }
1122
1123     return SASL_OK;
1124 }
1125
1126 /*
1127  * Create gs2-header, save channel bindings to context.
1128  */
1129 static int
1130 gs2_make_header(context_t *text,
1131                 sasl_client_params_t *cparams,
1132                 const char *authzid,
1133                 char **out,
1134                 unsigned *outlen)
1135 {
1136     size_t required = 0;
1137     size_t wire_authzid_len = 0, cbnamelen = 0;
1138     char *wire_authzid = NULL;
1139     char *p;
1140     int ret;
1141     gss_buffer_desc buf;
1142
1143     *out = NULL;
1144     *outlen = 0;
1145
1146     /* non-standard GSS framing flag */
1147     if (text->gs2_flags & GS2_NONSTD_FLAG)
1148         required += 2; /* F, */
1149
1150     /* SASL channel bindings */
1151     switch (text->gs2_flags & GS2_CB_FLAG_MASK) {
1152     case GS2_CB_FLAG_P:
1153         if (!SASL_CB_PRESENT(cparams))
1154             return SASL_BADPARAM;
1155         cbnamelen = strlen(cparams->cbinding->name);
1156         required += 1 /*=*/ + cbnamelen;
1157         /* fallthrough */
1158     case GS2_CB_FLAG_N:
1159     case GS2_CB_FLAG_Y:
1160         required += 2; /* [pny], */
1161         break;
1162     default:
1163         return SASL_BADPARAM;
1164     }
1165
1166     /* authorization identity */
1167     if (authzid != NULL) {
1168         ret = gs2_escape_authzid(text->utils, authzid,
1169                                  strlen(authzid), &wire_authzid);
1170         if (ret != SASL_OK)
1171             return ret;
1172
1173         wire_authzid_len = strlen(wire_authzid);
1174         required += 2 /* a= */ + wire_authzid_len;
1175     }
1176
1177     required += 1; /* trailing comma */
1178
1179     ret = _plug_buf_alloc(text->utils, out, outlen, required);
1180     if (ret != SASL_OK) {
1181         text->utils->free(wire_authzid);
1182         return ret;
1183     }
1184
1185     *out = text->out_buf;
1186     *outlen = required;
1187
1188     p = (char *)text->out_buf;
1189     if (text->gs2_flags & GS2_NONSTD_FLAG) {
1190         *p++ = 'F';
1191         *p++ = ',';
1192     }
1193     switch (text->gs2_flags & GS2_CB_FLAG_MASK) {
1194     case GS2_CB_FLAG_P:
1195         memcpy(p, "p=", 2);
1196         memcpy(p + 2, cparams->cbinding->name, cbnamelen);
1197         p += 2 + cbnamelen;
1198         break;
1199     case GS2_CB_FLAG_N:
1200         *p++ = 'n';
1201         break;
1202     case GS2_CB_FLAG_Y:
1203         *p++ = 'y';
1204         break;
1205     }
1206     *p++ = ',';
1207     if (wire_authzid != NULL) {
1208         memcpy(p, "a=", 2);
1209         memcpy(p + 2, wire_authzid, wire_authzid_len);
1210         text->utils->free(wire_authzid);
1211         p += 2 + wire_authzid_len;
1212     }
1213     *p++ = ',';
1214
1215     assert(p == (char *)text->out_buf + required);
1216
1217     buf.length = required;
1218     buf.value = *out;
1219
1220     ret = gs2_save_cbindings(text, &buf, cparams->cbinding);
1221     if (ret != SASL_OK)
1222         return ret;
1223
1224     return SASL_OK;
1225 }
1226
1227 /*
1228  * Convert a GSS token to a GS2 one
1229  */
1230 static int
1231 gs2_make_message(context_t *text,
1232                  sasl_client_params_t *cparams __attribute__((unused)),
1233                  int initialContextToken,
1234                  gss_buffer_t token,
1235                  char **out,
1236                  unsigned *outlen)
1237 {
1238     OM_uint32 major, minor;
1239     unsigned char *mech_token_data;
1240     size_t mech_token_size;
1241     char *p;
1242     unsigned header_len = 0;
1243     int ret;
1244
1245     mech_token_size = token->length;
1246     mech_token_data = (unsigned char *)token->value;
1247
1248     if (initialContextToken) {
1249         header_len = *outlen;
1250
1251         major = gs2_verify_token_header(&minor, text->mechanism,
1252                                         &mech_token_size, &mech_token_data,
1253                                         token->length);
1254         if ((major == GSS_S_DEFECTIVE_TOKEN &&
1255              (text->plug.client->features & SASL_FEAT_GSS_FRAMING)) ||
1256             GSS_ERROR(major))
1257             return SASL_FAIL;
1258     }
1259
1260     ret = _plug_buf_alloc(text->utils, out, outlen,
1261                           header_len + mech_token_size);
1262     if (ret != 0)
1263         return ret;
1264
1265     p = *out + header_len;
1266     memcpy(p, mech_token_data, mech_token_size);
1267
1268     *outlen = header_len + mech_token_size;
1269
1270     return SASL_OK;
1271 }
1272
1273 static const unsigned long gs2_required_prompts[] = {
1274     SASL_CB_LIST_END
1275 };
1276
1277 /*
1278  * Map GSS mechanism attributes to SASL ones
1279  */
1280 static int
1281 gs2_get_mech_attrs(const sasl_utils_t *utils,
1282                    const gss_OID mech,
1283                    unsigned int *security_flags,
1284                    unsigned int *features,
1285                    const unsigned long **prompts)
1286 {
1287     OM_uint32 major, minor;
1288     int present;
1289     gss_OID_set attrs = GSS_C_NO_OID_SET;
1290
1291     major = gss_inquire_attrs_for_mech(&minor, mech, &attrs, NULL);
1292     if (GSS_ERROR(major)) {
1293         utils->seterror(utils->conn, SASL_NOLOG,
1294                         "GS2 Failure: gss_inquire_attrs_for_mech");
1295         return SASL_FAIL;
1296     }
1297
1298     *security_flags = SASL_SEC_NOPLAINTEXT | SASL_SEC_NOACTIVE;
1299     *features = SASL_FEAT_WANT_CLIENT_FIRST | SASL_FEAT_CHANNEL_BINDING;
1300     if (prompts != NULL)
1301         *prompts = gs2_required_prompts;
1302
1303 #define MA_PRESENT(a)   (gss_test_oid_set_member(&minor, (gss_OID)(a), \
1304                                                  attrs, &present) == GSS_S_COMPLETE && \
1305                          present)
1306
1307     if (MA_PRESENT(GSS_C_MA_PFS))
1308         *security_flags |= SASL_SEC_FORWARD_SECRECY;
1309     if (!MA_PRESENT(GSS_C_MA_AUTH_INIT_ANON))
1310         *security_flags |= SASL_SEC_NOANONYMOUS;
1311     if (MA_PRESENT(GSS_C_MA_DELEG_CRED))
1312         *security_flags |= SASL_SEC_PASS_CREDENTIALS;
1313     if (MA_PRESENT(GSS_C_MA_AUTH_TARG))
1314         *security_flags |= SASL_SEC_MUTUAL_AUTH;
1315     if (MA_PRESENT(GSS_C_MA_AUTH_INIT_INIT) && prompts != NULL)
1316         *prompts = NULL;
1317     if (MA_PRESENT(GSS_C_MA_ITOK_FRAMED))
1318         *features |= SASL_FEAT_GSS_FRAMING;
1319
1320     gss_release_oid_set(&minor, &attrs);
1321
1322     return SASL_OK;
1323 }
1324
1325 /*
1326  * Enumerate GSS mechanisms that can be used for GS2
1327  */
1328 static int gs2_indicate_mechs(const sasl_utils_t *utils)
1329 {
1330     OM_uint32 major, minor;
1331     gss_OID_desc desired_oids[3];
1332     gss_OID_set_desc desired_attrs;
1333     gss_OID_desc except_oids[3];
1334     gss_OID_set_desc except_attrs;
1335
1336     if (gs2_mechs != GSS_C_NO_OID_SET)
1337         return SASL_OK;
1338
1339     desired_oids[0] = *GSS_C_MA_AUTH_INIT;
1340     desired_oids[1] = *GSS_C_MA_AUTH_TARG;
1341     desired_oids[2] = *GSS_C_MA_CBINDINGS;
1342     desired_attrs.count = sizeof(desired_oids)/sizeof(desired_oids[0]);
1343     desired_attrs.elements = desired_oids;
1344
1345     except_oids[0] = *GSS_C_MA_MECH_NEGO;
1346     except_oids[1] = *GSS_C_MA_NOT_MECH;
1347     except_oids[2] = *GSS_C_MA_DEPRECATED;
1348
1349     except_attrs.count = sizeof(except_oids)/sizeof(except_oids[0]);
1350     except_attrs.elements = except_oids;
1351
1352     major = gss_indicate_mechs_by_attrs(&minor,
1353                                         &desired_attrs,
1354                                         &except_attrs,
1355                                         GSS_C_NO_OID_SET,
1356                                         &gs2_mechs);
1357     if (GSS_ERROR(major)) {
1358         utils->seterror(utils->conn, SASL_NOLOG,
1359                         "GS2 Failure: gss_indicate_mechs_by_attrs");
1360         return SASL_FAIL;
1361     }
1362
1363     return (gs2_mechs->count > 0) ? SASL_OK : SASL_NOMECH;
1364 }
1365
1366 /*
1367  * Map SASL mechanism name to OID
1368  */
1369 static int
1370 gs2_map_sasl_name(const sasl_utils_t *utils,
1371                   const char *mech,
1372                   gss_OID *oid)
1373 {
1374     OM_uint32 major, minor;
1375     gss_buffer_desc buf;
1376
1377     buf.length = strlen(mech);
1378     buf.value = (void *)mech;
1379
1380     major = gss_inquire_mech_for_saslname(&minor, &buf, oid);
1381     if (GSS_ERROR(major)) {
1382         utils->seterror(utils->conn, SASL_NOLOG,
1383                         "GS2 Failure: gss_inquire_mech_for_saslname");
1384         return SASL_FAIL;
1385     }
1386
1387     return SASL_OK;
1388 }
1389
1390 static int
1391 gs2_duplicate_buffer(const sasl_utils_t *utils,
1392                      const gss_buffer_t src,
1393                      gss_buffer_t dst)
1394 {
1395     dst->value = utils->malloc(src->length + 1);
1396     if (dst->value == NULL)
1397         return SASL_NOMEM;
1398
1399     memcpy(dst->value, src->value, src->length);
1400     ((char *)dst->value)[src->length] = '\0';
1401     dst->length = src->length;
1402
1403     return SASL_OK;
1404 }
1405
1406 static int
1407 gs2_unescape_authzid(const sasl_utils_t *utils,
1408                      char **endp,
1409                      unsigned *remain,
1410                      char **authzid)
1411 {
1412     char *in = *endp;
1413     size_t i, len, inlen = *remain;
1414     char *p;
1415
1416     *endp = NULL;
1417
1418     for (i = 0, len = 0; i < inlen; i++) {
1419         if (in[i] == ',') {
1420             *endp = &in[i];
1421             *remain -= i;
1422             break;
1423         } else if (in[i] == '=') {
1424             if (inlen <= i + 2)
1425                 return SASL_BADPROT;
1426             i += 2;
1427         }
1428         len++;
1429     }
1430
1431     if (len == 0 || *endp == NULL)
1432         return SASL_BADPROT;
1433
1434     p = *authzid = utils->malloc(len + 1);
1435     if (*authzid == NULL)
1436         return SASL_NOMEM;
1437
1438     for (i = 0; i < inlen; i++) {
1439         if (in[i] == ',')
1440             break;
1441         else if (in[i] == '=') {
1442             if (memcmp(&in[i + 1], "2C", 2) == 0)
1443                 *p++ = ',';
1444             else if (memcmp(&in[i + 1], "3D", 2) == 0)
1445                 *p++ = '=';
1446             else {
1447                 utils->free(*authzid);
1448                 *authzid = NULL;
1449                 return SASL_BADPROT;
1450             }
1451             i += 2;
1452         } else
1453             *p++ = in[i];
1454     }
1455
1456     *p = '\0';
1457
1458     return SASL_OK;
1459 }
1460
1461 static int
1462 gs2_escape_authzid(const sasl_utils_t *utils,
1463                    const char *in,
1464                    unsigned inlen,
1465                    char **authzid)
1466 {
1467     size_t i;
1468     char *p;
1469
1470     p = *authzid = utils->malloc((inlen * 3) + 1);
1471     if (*authzid == NULL)
1472         return SASL_NOMEM;
1473
1474     for (i = 0; i < inlen; i++) {
1475         if (in[i] == ',') {
1476             memcpy(p, "=2C", 3);
1477             p += 3;
1478         } else if (in[i] == '=') {
1479             memcpy(p, "=3D", 3);
1480             p += 3;
1481         } else {
1482             *p++ = in[i];
1483         }
1484     }
1485
1486     *p = '\0';
1487
1488     return SASL_OK;
1489 }
1490
1491 #define GOT_CREDS(text, params) ((text)->client_creds != NULL || (params)->gss_creds != NULL)
1492
1493 static int
1494 gs2_get_init_creds(context_t *text,
1495                    sasl_client_params_t *params,
1496                    sasl_interact_t **prompt_need,
1497                    sasl_out_params_t *oparams)
1498 {
1499     int result = SASL_OK;
1500     const char *authid = NULL, *userid = NULL;
1501     int user_result = SASL_OK;
1502     int auth_result = SASL_OK;
1503     int pass_result = SASL_OK;
1504     OM_uint32 maj_stat, min_stat;
1505     gss_OID_set_desc mechs;
1506     gss_buffer_desc cred_authid = GSS_C_EMPTY_BUFFER;
1507
1508     mechs.count = 1;
1509     mechs.elements = (gss_OID)text->mechanism;
1510
1511     /*
1512      * Determine the authentication identity from the application supplied
1513      * GSS credential, the default GSS credential, and the application
1514      * supplied identity, in that order.
1515      */
1516     if (oparams->authid == NULL) {
1517         assert(text->client_name == GSS_C_NO_NAME);
1518
1519         if (!GOT_CREDS(text, params)) {
1520             maj_stat = gss_acquire_cred(&min_stat,
1521                                         GSS_C_NO_NAME,
1522                                         GSS_C_INDEFINITE,
1523                                         &mechs,
1524                                         GSS_C_INITIATE,
1525                                         &text->client_creds,
1526                                         NULL,
1527                                         &text->lifetime);
1528         } else
1529             maj_stat = GSS_S_COMPLETE;
1530
1531         if (maj_stat == GSS_S_COMPLETE) {
1532             maj_stat = gss_inquire_cred(&min_stat,
1533                                         params->gss_creds
1534                                             ? (gss_cred_id_t)params->gss_creds
1535                                             : text->client_creds,
1536                                         &text->client_name,
1537                                         NULL,
1538                                         NULL,
1539                                         NULL);
1540             if (GSS_ERROR(maj_stat))
1541                 goto cleanup;
1542         } else if (maj_stat != GSS_S_CRED_UNAVAIL)
1543             goto cleanup;
1544
1545         if (text->client_name != GSS_C_NO_NAME) {
1546             maj_stat = gss_display_name(&min_stat,
1547                                         text->client_name,
1548                                         &cred_authid,
1549                                         NULL);
1550             if (GSS_ERROR(maj_stat))
1551                 goto cleanup;
1552
1553             authid = cred_authid.value;
1554         } else {
1555             auth_result = _plug_get_authid(params->utils, &authid, prompt_need);
1556             if (auth_result != SASL_OK && auth_result != SASL_INTERACT) {
1557                 result = auth_result;
1558                 goto cleanup;
1559             }
1560         }
1561     }
1562
1563     /*
1564      * If the application has provided an authentication identity, parse it.
1565      */
1566     if (text->client_name == GSS_C_NO_NAME) {
1567         gss_buffer_desc name_buf;
1568
1569         if (oparams->authid != NULL) {
1570             name_buf.length = strlen(oparams->authid);
1571             name_buf.value = (void *)oparams->authid;
1572         } else {
1573             name_buf.length = strlen(authid);
1574             name_buf.value = (void *)authid;
1575         }
1576
1577         if (name_buf.value != NULL) {
1578             maj_stat = gss_import_name(&min_stat,
1579                                        &name_buf,
1580                                        GSS_C_NT_USER_NAME,
1581                                        &text->client_name);
1582             if (GSS_ERROR(maj_stat))
1583                 goto cleanup;
1584         }
1585     }
1586
1587     /*
1588      * Get the authorization identity.
1589      */
1590     if (oparams->user == NULL) {
1591         user_result = _plug_get_userid(params->utils, &userid, prompt_need);
1592         if (user_result != SASL_OK && user_result != SASL_INTERACT) {
1593             result = user_result;
1594             goto cleanup;
1595         }
1596     }
1597
1598     /*
1599      * Armed with the authentication identity, try to get a credential without
1600      * a password.
1601      */
1602     if (!GOT_CREDS(text, params) && text->client_name != GSS_C_NO_NAME) {
1603         maj_stat = gss_acquire_cred(&min_stat,
1604                                     text->client_name,
1605                                     GSS_C_INDEFINITE,
1606                                     &mechs,
1607                                     GSS_C_INITIATE,
1608                                     &text->client_creds,
1609                                     NULL,
1610                                     &text->lifetime);
1611         if (maj_stat != GSS_S_COMPLETE && maj_stat != GSS_S_CRED_UNAVAIL)
1612             goto cleanup;
1613     }
1614
1615     /*
1616      * If that failed, try to get a credential with a password.
1617      */
1618     if (!GOT_CREDS(text, params)) {
1619         if (text->password == NULL) {
1620             pass_result = _plug_get_password(params->utils, &text->password,
1621                                              &text->free_password, prompt_need);
1622             if (pass_result != SASL_OK && pass_result != SASL_INTERACT) {
1623                 result = pass_result;
1624                 goto cleanup;
1625             }
1626         }
1627
1628         if (text->password != NULL) {
1629             gss_buffer_desc password_buf;
1630
1631             password_buf.length = text->password->len;
1632             password_buf.value = text->password->data;
1633
1634             maj_stat = gss_acquire_cred_with_password(&min_stat,
1635                                                       text->client_name,
1636                                                       &password_buf,
1637                                                       GSS_C_INDEFINITE,
1638                                                       &mechs,
1639                                                       GSS_C_INITIATE,
1640                                                       &text->client_creds,
1641                                                       NULL,
1642                                                       &text->lifetime);
1643             if (GSS_ERROR(maj_stat))
1644                 goto cleanup;
1645         }
1646     }
1647
1648     maj_stat = GSS_S_COMPLETE;
1649
1650     /* free prompts we got */
1651     if (prompt_need && *prompt_need) {
1652         params->utils->free(*prompt_need);
1653         *prompt_need = NULL;
1654     }
1655
1656     /* if there are prompts not filled in */
1657     if (user_result == SASL_INTERACT || auth_result == SASL_INTERACT ||
1658         pass_result == SASL_INTERACT) {
1659         /* make the prompt list */
1660         result =
1661             _plug_make_prompts(params->utils, prompt_need,
1662                                user_result == SASL_INTERACT ?
1663                                "Please enter your authorization name" : NULL,
1664                                NULL,
1665                                auth_result == SASL_INTERACT ?
1666                                "Please enter your authentication name" : NULL,
1667                                NULL,
1668                                pass_result == SASL_INTERACT ?
1669                                "Please enter your password" : NULL, NULL,
1670                                NULL, NULL, NULL,
1671                                NULL,
1672                                NULL, NULL);
1673         if (result == SASL_OK)
1674             result = SASL_INTERACT;
1675     } else if (oparams->authid == NULL) {
1676         if (userid == NULL || userid[0] == '\0') {
1677             result = params->canon_user(params->utils->conn, authid, 0,
1678                                         SASL_CU_AUTHID | SASL_CU_AUTHZID,
1679                                         oparams);
1680         } else {
1681             result = params->canon_user(params->utils->conn,
1682                                         authid, 0, SASL_CU_AUTHID, oparams);
1683             if (result != SASL_OK)
1684                 goto cleanup;
1685
1686             result = params->canon_user(params->utils->conn,
1687                                         userid, 0, SASL_CU_AUTHZID, oparams);
1688             if (result != SASL_OK)
1689                 goto cleanup;
1690         }
1691     }
1692
1693 cleanup:
1694     if (result == SASL_OK && maj_stat != GSS_S_COMPLETE) {
1695         sasl_gs2_seterror(text->utils, maj_stat, min_stat);
1696         result = SASL_FAIL;
1697     }
1698
1699     gss_release_buffer(&min_stat, &cred_authid);
1700
1701     return result;
1702 }
1703
1704 static int
1705 sasl_gs2_seterror_(const sasl_utils_t *utils, OM_uint32 maj, OM_uint32 min,
1706                    int logonly)
1707 {
1708     OM_uint32 maj_stat, min_stat;
1709     gss_buffer_desc msg;
1710     OM_uint32 msg_ctx;
1711     int ret;
1712     char *out = NULL;
1713     unsigned int len, curlen = 0;
1714     const char prefix[] = "GSSAPI Error: ";
1715
1716     len = sizeof(prefix);
1717     ret = _plug_buf_alloc(utils, &out, &curlen, 256);
1718     if (ret != SASL_OK)
1719         return SASL_OK;
1720
1721     strcpy(out, prefix);
1722
1723     msg_ctx = 0;
1724     while (1) {
1725         maj_stat = gss_display_status(&min_stat, maj,
1726                                       GSS_C_GSS_CODE, GSS_C_NULL_OID,
1727                                       &msg_ctx, &msg);
1728
1729         if (GSS_ERROR(maj_stat)) {
1730             if (logonly) {
1731                 utils->log(utils->conn, SASL_LOG_FAIL,
1732                         "GS2 Failure: (could not get major error message)");
1733             } else {
1734                 utils->seterror(utils->conn, 0,
1735                                 "GS2 Failure "
1736                                 "(could not get major error message)");
1737             }
1738             utils->free(out);
1739             return SASL_OK;
1740         }
1741
1742         len += len + msg.length;
1743         ret = _plug_buf_alloc(utils, &out, &curlen, len);
1744         if (ret != SASL_OK) {
1745             utils->free(out);
1746             return SASL_OK;
1747         }
1748
1749         strcat(out, msg.value);
1750
1751         gss_release_buffer(&min_stat, &msg);
1752
1753         if (!msg_ctx)
1754             break;
1755     }
1756
1757     /* Now get the minor status */
1758
1759     len += 2;
1760     ret = _plug_buf_alloc(utils, &out, &curlen, len);
1761     if (ret != SASL_OK) {
1762         utils->free(out);
1763         return SASL_NOMEM;
1764     }
1765
1766     strcat(out, " (");
1767
1768     msg_ctx = 0;
1769     while (1) {
1770         maj_stat = gss_display_status(&min_stat, min,
1771                                       GSS_C_MECH_CODE, GSS_C_NULL_OID,
1772                                       &msg_ctx, &msg);
1773
1774         if (GSS_ERROR(maj_stat)) {
1775             if (logonly) {
1776                 utils->log(utils->conn, SASL_LOG_FAIL,
1777                         "GS2 Failure: (could not get minor error message)");
1778             } else {
1779                 utils->seterror(utils->conn, 0,
1780                                 "GS2 Failure "
1781                                 "(could not get minor error message)");
1782             }
1783             utils->free(out);
1784             return SASL_OK;
1785         }
1786
1787         len += len + msg.length;
1788
1789         ret = _plug_buf_alloc(utils, &out, &curlen, len);
1790         if (ret != SASL_OK) {
1791             utils->free(out);
1792             return SASL_NOMEM;
1793         }
1794
1795         strcat(out, msg.value);
1796
1797         gss_release_buffer(&min_stat, &msg);
1798
1799         if (!msg_ctx)
1800             break;
1801     }
1802
1803     len += 1;
1804     ret = _plug_buf_alloc(utils, &out, &curlen, len);
1805     if (ret != SASL_OK) {
1806         utils->free(out);
1807         return SASL_NOMEM;
1808     }
1809
1810     strcat(out, ")");
1811
1812     if (logonly) {
1813         utils->log(utils->conn, SASL_LOG_FAIL, out);
1814     } else {
1815         utils->seterror(utils->conn, 0, out);
1816     }
1817     utils->free(out);
1818
1819     return SASL_OK;
1820 }