source4/auth/kerberos/krb5_init_context.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Wrapper for krb5_init_context
   4
   5    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
   6    Copyright (C) Andrew Tridgell 2005
   7    Copyright (C) Stefan Metzmacher 2004
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "system/kerberos.h"
  25 #include "system/gssapi.h"
  26 #include <tevent.h>
  27 #include "auth/kerberos/kerberos.h"
  28 #include "lib/socket/socket.h"
  29 #include "lib/stream/packet.h"
  30 #include "system/network.h"
  31 #include "param/param.h"
  32 #include "libcli/resolve/resolve.h"
  33 #include "../lib/tsocket/tsocket.h"
  34 #include "krb5_init_context.h"
  35 /*
  36   context structure for operations on cldap packets
  37 */
  38 struct smb_krb5_socket {
  39         struct socket_context *sock;
  40
  41         /* the fd event */
  42         struct tevent_fd *fde;
  43
  44         NTSTATUS status;
  45         DATA_BLOB request, reply;
  46
  47         struct packet_context *packet;
  48
  49         size_t partial_read;
  50 #ifdef SAMBA4_USES_HEIMDAL
  51         krb5_krbhst_info *hi;
  52 #endif
  53 };
  54
  55 static krb5_error_code smb_krb5_context_destroy(struct smb_krb5_context *ctx)
  56 {
  57 #ifdef SAMBA4_USES_HEIMDAL
  58         if (ctx->pvt_log_data) {
  59                 /* Otherwise krb5_free_context will try and close what we
  60                  * have already free()ed */
  61                 krb5_set_warn_dest(ctx->krb5_context, NULL);
  62                 krb5_closelog(ctx->krb5_context,
  63                                 (krb5_log_facility *)ctx->pvt_log_data);
  64         }
  65 #else
  66         krb5_set_trace_callback(ctx->krb5_context, NULL, NULL);
  67 #endif
  68         krb5_free_context(ctx->krb5_context);
  69         return 0;
  70 }
  71
  72 #ifdef SAMBA4_USES_HEIMDAL
  73 /* We never close down the DEBUG system, and no need to unreference the use */
  74 static void smb_krb5_debug_close(void *private_data) {
  75         return;
  76 }
  77 #endif
  78
  79 #ifdef SAMBA4_USES_HEIMDAL
  80 static void smb_krb5_debug_wrapper(const char *timestr, const char *msg, void *private_data)
  81 {
  82         DEBUG(3, ("Kerberos: %s\n", msg));
  83 }
  84 #else
  85 static void smb_krb5_debug_wrapper(krb5_context context,
  86                                    const struct krb5_trace_info *info,
  87                                    void *cb_data)
  88 {
  89         DEBUG(3, ("Kerberos: %s\n", info->message));
  90 }
  91 #endif
  92
  93 #ifdef SAMBA4_USES_HEIMDAL
  94 /*
  95   handle recv events on a smb_krb5 socket
  96 */
  97 static void smb_krb5_socket_recv(struct smb_krb5_socket *smb_krb5)
  98 {
  99         TALLOC_CTX *tmp_ctx = talloc_new(smb_krb5);
 100         DATA_BLOB blob;
 101         size_t nread, dsize;
 102
 103         smb_krb5->status = socket_pending(smb_krb5->sock, &dsize);
 104         if (!NT_STATUS_IS_OK(smb_krb5->status)) {
 105                 talloc_free(tmp_ctx);
 106                 return;
 107         }
 108
 109         blob = data_blob_talloc(tmp_ctx, NULL, dsize);
 110         if (blob.data == NULL && dsize != 0) {
 111                 smb_krb5->status = NT_STATUS_NO_MEMORY;
 112                 talloc_free(tmp_ctx);
 113                 return;
 114         }
 115
 116         smb_krb5->status = socket_recv(smb_krb5->sock, blob.data, blob.length, &nread);
 117         if (!NT_STATUS_IS_OK(smb_krb5->status)) {
 118                 talloc_free(tmp_ctx);
 119                 return;
 120         }
 121         blob.length = nread;
 122
 123         if (nread == 0) {
 124                 smb_krb5->status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
 125                 talloc_free(tmp_ctx);
 126                 return;
 127         }
 128
 129         DEBUG(4,("Received smb_krb5 packet of length %d\n",
 130                  (int)blob.length));
 131
 132         talloc_steal(smb_krb5, blob.data);
 133         smb_krb5->reply = blob;
 134         talloc_free(tmp_ctx);
 135 }
 136
 137 static NTSTATUS smb_krb5_full_packet(void *private_data, DATA_BLOB data)
 138 {
 139         struct smb_krb5_socket *smb_krb5 = talloc_get_type(private_data, struct smb_krb5_socket);
 140         talloc_steal(smb_krb5, data.data);
 141         smb_krb5->reply = data;
 142         smb_krb5->reply.length -= 4;
 143         smb_krb5->reply.data += 4;
 144         return NT_STATUS_OK;
 145 }
 146
 147 /*
 148   handle request timeouts
 149 */
 150 static void smb_krb5_request_timeout(struct tevent_context *event_ctx,
 151                                   struct tevent_timer *te, struct timeval t,
 152                                   void *private_data)
 153 {
 154         struct smb_krb5_socket *smb_krb5 = talloc_get_type(private_data, struct smb_krb5_socket);
 155         DEBUG(5,("Timed out smb_krb5 packet\n"));
 156         smb_krb5->status = NT_STATUS_IO_TIMEOUT;
 157 }
 158
 159 static void smb_krb5_error_handler(void *private_data, NTSTATUS status)
 160 {
 161         struct smb_krb5_socket *smb_krb5 = talloc_get_type(private_data, struct smb_krb5_socket);
 162         smb_krb5->status = status;
 163 }
 164
 165 /*
 166   handle send events on a smb_krb5 socket
 167 */
 168 static void smb_krb5_socket_send(struct smb_krb5_socket *smb_krb5)
 169 {
 170         NTSTATUS status;
 171
 172         size_t len;
 173
 174         len = smb_krb5->request.length;
 175         status = socket_send(smb_krb5->sock, &smb_krb5->request, &len);
 176
 177         if (!NT_STATUS_IS_OK(status)) return;
 178
 179         TEVENT_FD_READABLE(smb_krb5->fde);
 180
 181         TEVENT_FD_NOT_WRITEABLE(smb_krb5->fde);
 182         return;
 183 }
 184
 185
 186 /*
 187   handle fd events on a smb_krb5_socket
 188 */
 189 static void smb_krb5_socket_handler(struct tevent_context *ev, struct tevent_fd *fde,
 190                                  uint16_t flags, void *private_data)
 191 {
 192         struct smb_krb5_socket *smb_krb5 = talloc_get_type(private_data, struct smb_krb5_socket);
 193         switch (smb_krb5->hi->proto) {
 194         case KRB5_KRBHST_UDP:
 195                 if (flags & TEVENT_FD_READ) {
 196                         smb_krb5_socket_recv(smb_krb5);
 197                         return;
 198                 }
 199                 if (flags & TEVENT_FD_WRITE) {
 200                         smb_krb5_socket_send(smb_krb5);
 201                         return;
 202                 }
 203                 /* not reached */
 204                 return;
 205         case KRB5_KRBHST_TCP:
 206                 if (flags & TEVENT_FD_READ) {
 207                         packet_recv(smb_krb5->packet);
 208                         return;
 209                 }
 210                 if (flags & TEVENT_FD_WRITE) {
 211                         packet_queue_run(smb_krb5->packet);
 212                         return;
 213                 }
 214                 /* not reached */
 215                 return;
 216         case KRB5_KRBHST_HTTP:
 217                 /* can't happen */
 218                 break;
 219         }
 220 }
 221
 222 krb5_error_code smb_krb5_send_and_recv_func(krb5_context context,
 223                                             void *data,
 224                                             krb5_krbhst_info *hi,
 225                                             time_t timeout,
 226                                             const krb5_data *send_buf,
 227                                             krb5_data *recv_buf)
 228 {
 229         krb5_error_code ret;
 230         NTSTATUS status;
 231         const char *name;
 232         struct addrinfo *ai, *a;
 233         struct smb_krb5_socket *smb_krb5;
 234
 235         DATA_BLOB send_blob;
 236
 237         struct tevent_context *ev;
 238         TALLOC_CTX *tmp_ctx = talloc_new(NULL);
 239         if (!tmp_ctx) {
 240                 return ENOMEM;
 241         }
 242
 243         if (!data) {
 244                 /* If no event context was available, then create one for this loop */
 245                 ev = tevent_context_init(tmp_ctx);
 246                 if (!ev) {
 247                         talloc_free(tmp_ctx);
 248                         return ENOMEM;
 249                 }
 250         } else {
 251                 ev = talloc_get_type_abort(data, struct tevent_context);
 252         }
 253
 254         send_blob = data_blob_const(send_buf->data, send_buf->length);
 255
 256         ret = krb5_krbhst_get_addrinfo(context, hi, &ai);
 257         if (ret) {
 258                 talloc_free(tmp_ctx);
 259                 return ret;
 260         }
 261
 262         for (a = ai; a; a = a->ai_next) {
 263                 struct socket_address *remote_addr;
 264                 smb_krb5 = talloc(tmp_ctx, struct smb_krb5_socket);
 265                 if (!smb_krb5) {
 266                         talloc_free(tmp_ctx);
 267                         return ENOMEM;
 268                 }
 269                 smb_krb5->hi = hi;
 270
 271                 switch (a->ai_family) {
 272                 case PF_INET:
 273                         name = "ipv4";
 274                         break;
 275 #ifdef HAVE_IPV6
 276                 case PF_INET6:
 277                         name = "ipv6";
 278                         break;
 279 #endif
 280                 default:
 281                         talloc_free(tmp_ctx);
 282                         return EINVAL;
 283                 }
 284
 285                 status = NT_STATUS_INVALID_PARAMETER;
 286                 switch (hi->proto) {
 287                 case KRB5_KRBHST_UDP:
 288                         status = socket_create(name, SOCKET_TYPE_DGRAM, &smb_krb5->sock, 0);
 289                         break;
 290                 case KRB5_KRBHST_TCP:
 291                         status = socket_create(name, SOCKET_TYPE_STREAM, &smb_krb5->sock, 0);
 292                         break;
 293                 case KRB5_KRBHST_HTTP:
 294                         talloc_free(tmp_ctx);
 295                         return EINVAL;
 296                 }
 297                 if (!NT_STATUS_IS_OK(status)) {
 298                         talloc_free(smb_krb5);
 299                         continue;
 300                 }
 301
 302                 talloc_steal(smb_krb5, smb_krb5->sock);
 303
 304                 remote_addr = socket_address_from_sockaddr(smb_krb5, a->ai_addr, a->ai_addrlen);
 305                 if (!remote_addr) {
 306                         talloc_free(smb_krb5);
 307                         continue;
 308                 }
 309
 310                 status = socket_connect_ev(smb_krb5->sock, NULL, remote_addr, 0, ev);
 311                 if (!NT_STATUS_IS_OK(status)) {
 312                         talloc_free(smb_krb5);
 313                         continue;
 314                 }
 315
 316                 /* Setup the FDE, start listening for read events
 317                  * from the start (otherwise we may miss a socket
 318                  * drop) and mark as AUTOCLOSE along with the fde */
 319
 320                 /* Ths is equivilant to EVENT_FD_READABLE(smb_krb5->fde) */
 321                 smb_krb5->fde = tevent_add_fd(ev, smb_krb5->sock,
 322                                               socket_get_fd(smb_krb5->sock),
 323                                               TEVENT_FD_READ,
 324                                               smb_krb5_socket_handler, smb_krb5);
 325                 /* its now the job of the event layer to close the socket */
 326                 tevent_fd_set_close_fn(smb_krb5->fde, socket_tevent_fd_close_fn);
 327                 socket_set_flags(smb_krb5->sock, SOCKET_FLAG_NOCLOSE);
 328
 329                 tevent_add_timer(ev, smb_krb5,
 330                                  timeval_current_ofs(timeout, 0),
 331                                  smb_krb5_request_timeout, smb_krb5);
 332
 333                 smb_krb5->status = NT_STATUS_OK;
 334                 smb_krb5->reply = data_blob(NULL, 0);
 335
 336                 switch (hi->proto) {
 337                 case KRB5_KRBHST_UDP:
 338                         TEVENT_FD_WRITEABLE(smb_krb5->fde);
 339                         smb_krb5->request = send_blob;
 340                         break;
 341                 case KRB5_KRBHST_TCP:
 342
 343                         smb_krb5->packet = packet_init(smb_krb5);
 344                         if (smb_krb5->packet == NULL) {
 345                                 talloc_free(smb_krb5);
 346                                 return ENOMEM;
 347                         }
 348                         packet_set_private(smb_krb5->packet, smb_krb5);
 349                         packet_set_socket(smb_krb5->packet, smb_krb5->sock);
 350                         packet_set_callback(smb_krb5->packet, smb_krb5_full_packet);
 351                         packet_set_full_request(smb_krb5->packet, packet_full_request_u32);
 352                         packet_set_error_handler(smb_krb5->packet, smb_krb5_error_handler);
 353                         packet_set_event_context(smb_krb5->packet, ev);
 354                         packet_set_fde(smb_krb5->packet, smb_krb5->fde);
 355
 356                         smb_krb5->request = data_blob_talloc(smb_krb5, NULL, send_blob.length + 4);
 357                         RSIVAL(smb_krb5->request.data, 0, send_blob.length);
 358                         memcpy(smb_krb5->request.data+4, send_blob.data, send_blob.length);
 359                         packet_send(smb_krb5->packet, smb_krb5->request);
 360                         break;
 361                 case KRB5_KRBHST_HTTP:
 362                         talloc_free(tmp_ctx);
 363                         return EINVAL;
 364                 }
 365                 while ((NT_STATUS_IS_OK(smb_krb5->status)) && !smb_krb5->reply.length) {
 366                         if (tevent_loop_once(ev) != 0) {
 367                                 talloc_free(tmp_ctx);
 368                                 return EINVAL;
 369                         }
 370
 371                         /* After each and every event loop, reset the
 372                          * send_to_kdc pointers to what they were when
 373                          * we entered this loop.  That way, if a
 374                          * nested event has invalidated them, we put
 375                          * it back before we return to the heimdal
 376                          * code */
 377                         ret = krb5_set_send_to_kdc_func(context,
 378                                                         smb_krb5_send_and_recv_func,
 379                                                         data);
 380                         if (ret != 0) {
 381                                 talloc_free(tmp_ctx);
 382                                 return ret;
 383                         }
 384                 }
 385                 if (NT_STATUS_EQUAL(smb_krb5->status, NT_STATUS_IO_TIMEOUT)) {
 386                         talloc_free(smb_krb5);
 387                         continue;
 388                 }
 389
 390                 if (!NT_STATUS_IS_OK(smb_krb5->status)) {
 391                         struct tsocket_address *addr = socket_address_to_tsocket_address(smb_krb5, remote_addr);
 392                         const char *addr_string = NULL;
 393                         if (addr) {
 394                                 addr_string = tsocket_address_inet_addr_string(addr, smb_krb5);
 395                         } else {
 396                                 addr_string = NULL;
 397                         }
 398                         DEBUG(2,("Error reading smb_krb5 reply packet: %s from %s\n", nt_errstr(smb_krb5->status),
 399                                  addr_string));
 400                         talloc_free(smb_krb5);
 401                         continue;
 402                 }
 403
 404                 ret = krb5_data_copy(recv_buf, smb_krb5->reply.data, smb_krb5->reply.length);
 405                 if (ret) {
 406                         talloc_free(tmp_ctx);
 407                         return ret;
 408                 }
 409                 talloc_free(smb_krb5);
 410
 411                 break;
 412         }
 413         talloc_free(tmp_ctx);
 414         if (a) {
 415                 return 0;
 416         }
 417         return KRB5_KDC_UNREACH;
 418 }
 419 #endif
 420
 421 krb5_error_code
 422 smb_krb5_init_context_basic(TALLOC_CTX *tmp_ctx,
 423                             struct loadparm_context *lp_ctx,
 424                             krb5_context *_krb5_context)
 425 {
 426         krb5_error_code ret;
 427 #ifdef SAMBA4_USES_HEIMDAL
 428         char **config_files;
 429         const char *config_file, *realm;
 430 #endif
 431         krb5_context krb5_ctx;
 432
 433         initialize_krb5_error_table();
 434
 435         ret = krb5_init_context(&krb5_ctx);
 436         if (ret) {
 437                 DEBUG(1,("krb5_init_context failed (%s)\n",
 438                          error_message(ret)));
 439                 return ret;
 440         }
 441
 442         /* The MIT Kerberos build relies on using the system krb5.conf file.
 443          * If you really want to use another file please set KRB5_CONFIG
 444          * accordingly. */
 445 #ifdef SAMBA4_USES_HEIMDAL
 446         config_file = lpcfg_config_path(tmp_ctx, lp_ctx, "krb5.conf");
 447         if (!config_file) {
 448                 krb5_free_context(krb5_ctx);
 449                 return ENOMEM;
 450         }
 451
 452         /* Use our local krb5.conf file by default */
 453         ret = krb5_prepend_config_files_default(config_file, &config_files);
 454         if (ret) {
 455                 DEBUG(1,("krb5_prepend_config_files_default failed (%s)\n",
 456                          smb_get_krb5_error_message(krb5_ctx, ret, tmp_ctx)));
 457                 krb5_free_context(krb5_ctx);
 458                 return ret;
 459         }
 460
 461         ret = krb5_set_config_files(krb5_ctx, config_files);
 462         krb5_free_config_files(config_files);
 463         if (ret) {
 464                 DEBUG(1,("krb5_set_config_files failed (%s)\n",
 465                          smb_get_krb5_error_message(krb5_ctx, ret, tmp_ctx)));
 466                 krb5_free_context(krb5_ctx);
 467                 return ret;
 468         }
 469
 470         realm = lpcfg_realm(lp_ctx);
 471         if (realm != NULL) {
 472                 ret = krb5_set_default_realm(krb5_ctx, realm);
 473                 if (ret) {
 474                         DEBUG(1,("krb5_set_default_realm failed (%s)\n",
 475                                  smb_get_krb5_error_message(krb5_ctx, ret, tmp_ctx)));
 476                         krb5_free_context(krb5_ctx);
 477                         return ret;
 478                 }
 479         }
 480 #endif
 481         *_krb5_context = krb5_ctx;
 482         return 0;
 483 }
 484
 485 krb5_error_code smb_krb5_init_context(void *parent_ctx,
 486                                       struct tevent_context *ev,
 487                                       struct loadparm_context *lp_ctx,
 488                                       struct smb_krb5_context **smb_krb5_context)
 489 {
 490         krb5_error_code ret;
 491         TALLOC_CTX *tmp_ctx;
 492         krb5_context kctx;
 493 #ifdef SAMBA4_USES_HEIMDAL
 494         krb5_log_facility *logf;
 495 #endif
 496
 497         initialize_krb5_error_table();
 498
 499         tmp_ctx = talloc_new(parent_ctx);
 500         *smb_krb5_context = talloc_zero(tmp_ctx, struct smb_krb5_context);
 501
 502         if (!*smb_krb5_context || !tmp_ctx) {
 503                 talloc_free(tmp_ctx);
 504                 return ENOMEM;
 505         }
 506
 507         ret = smb_krb5_init_context_basic(tmp_ctx, lp_ctx, &kctx);
 508         if (ret) {
 509                 DEBUG(1,("smb_krb5_context_init_basic failed (%s)\n",
 510                          error_message(ret)));
 511                 talloc_free(tmp_ctx);
 512                 return ret;
 513         }
 514         (*smb_krb5_context)->krb5_context = kctx;
 515
 516         talloc_set_destructor(*smb_krb5_context, smb_krb5_context_destroy);
 517
 518 #ifdef SAMBA4_USES_HEIMDAL
 519         /* TODO: Should we have a different name here? */
 520         ret = krb5_initlog(kctx, "Samba", &logf);
 521
 522         if (ret) {
 523                 DEBUG(1,("krb5_initlog failed (%s)\n",
 524                          smb_get_krb5_error_message(kctx, ret, tmp_ctx)));
 525                 talloc_free(tmp_ctx);
 526                 return ret;
 527         }
 528         (*smb_krb5_context)->pvt_log_data = logf;
 529
 530         ret = krb5_addlog_func(kctx, logf, 0 /* min */, -1 /* max */,
 531                                smb_krb5_debug_wrapper,
 532                                 smb_krb5_debug_close, NULL);
 533         if (ret) {
 534                 DEBUG(1,("krb5_addlog_func failed (%s)\n",
 535                          smb_get_krb5_error_message(kctx, ret, tmp_ctx)));
 536                 talloc_free(tmp_ctx);
 537                 return ret;
 538         }
 539         krb5_set_warn_dest(kctx, logf);
 540
 541         /* Set use of our socket lib */
 542         if (ev) {
 543                 struct tevent_context *previous_ev;
 544                 ret = smb_krb5_context_set_event_ctx(*smb_krb5_context,
 545                                                      ev, &previous_ev);
 546                 if (ret) {
 547                         talloc_free(tmp_ctx);
 548                         return ret;
 549                 }
 550         }
 551
 552         /* Set options in kerberos */
 553
 554         krb5_set_dns_canonicalize_hostname(kctx,
 555                         lpcfg_parm_bool(lp_ctx, NULL, "krb5",
 556                                         "set_dns_canonicalize", false));
 557 #else
 558         ret = krb5_set_trace_callback(kctx, smb_krb5_debug_wrapper, NULL);
 559         if (ret && ret != KRB5_TRACE_NOSUPP) {
 560                 DEBUG(1, ("krb5_set_trace_callback failed (%s)\n",
 561                           smb_get_krb5_error_message(kctx, ret, tmp_ctx)));
 562                 talloc_free(tmp_ctx);
 563                 return ret;
 564         }
 565 #endif
 566         talloc_steal(parent_ctx, *smb_krb5_context);
 567         talloc_free(tmp_ctx);
 568
 569         return 0;
 570 }
 571
 572 #ifdef SAMBA4_USES_HEIMDAL
 573 krb5_error_code smb_krb5_context_set_event_ctx(struct smb_krb5_context *smb_krb5_context,
 574                                                struct tevent_context *ev,
 575                                                struct tevent_context **previous_ev)
 576 {
 577         int ret;
 578         if (!ev) {
 579                 return EINVAL;
 580         }
 581
 582         *previous_ev = smb_krb5_context->current_ev;
 583
 584         smb_krb5_context->current_ev = talloc_reference(smb_krb5_context, ev);
 585         if (!smb_krb5_context->current_ev) {
 586                 return ENOMEM;
 587         }
 588
 589         /* Set use of our socket lib */
 590         ret = krb5_set_send_to_kdc_func(smb_krb5_context->krb5_context,
 591                                         smb_krb5_send_and_recv_func,
 592                                         ev);
 593         if (ret) {
 594                 TALLOC_CTX *tmp_ctx = talloc_new(NULL);
 595                 DEBUG(1,("krb5_set_send_recv_func failed (%s)\n",
 596                          smb_get_krb5_error_message(smb_krb5_context->krb5_context, ret, tmp_ctx)));
 597                 talloc_free(tmp_ctx);
 598                 talloc_unlink(smb_krb5_context, smb_krb5_context->current_ev);
 599                 smb_krb5_context->current_ev = NULL;
 600                 return ret;
 601         }
 602         return 0;
 603 }
 604
 605 krb5_error_code smb_krb5_context_remove_event_ctx(struct smb_krb5_context *smb_krb5_context,
 606                                                   struct tevent_context *previous_ev,
 607                                                   struct tevent_context *ev)
 608 {
 609         int ret;
 610         talloc_unlink(smb_krb5_context, ev);
 611         /* If there was a mismatch with things happening on a stack, then don't wipe things */
 612         smb_krb5_context->current_ev = previous_ev;
 613         /* Set use of our socket lib */
 614         ret = krb5_set_send_to_kdc_func(smb_krb5_context->krb5_context,
 615                                         smb_krb5_send_and_recv_func,
 616                                         previous_ev);
 617         if (ret) {
 618                 TALLOC_CTX *tmp_ctx = talloc_new(NULL);
 619                 DEBUG(1,("krb5_set_send_recv_func failed (%s)\n",
 620                          smb_get_krb5_error_message(smb_krb5_context->krb5_context, ret, tmp_ctx)));
 621                 talloc_free(tmp_ctx);
 622                 return ret;
 623         }
 624         return 0;
 625 }
 626 #endif