source4/ldap_server/ldap_bind.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    LDAP server
   4    Copyright (C) Stefan Metzmacher 2004
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "ldap_server/ldap_server.h"
  22 #include "auth/auth.h"
  23 #include "smbd/service.h"
  24 #include <ldb.h>
  25 #include <ldb_errors.h>
  26 #include "dsdb/samdb/samdb.h"
  27 #include "auth/gensec/gensec.h"
  28 #include "auth/gensec/gensec_tstream.h"
  29 #include "param/param.h"
  30 #include "../lib/util/tevent_ntstatus.h"
  31
  32 static NTSTATUS ldapsrv_BindSimple(struct ldapsrv_call *call)
  33 {
  34         struct ldap_BindRequest *req = &call->request->r.BindRequest;
  35         struct ldapsrv_reply *reply;
  36         struct ldap_BindResponse *resp;
  37
  38         int result;
  39         const char *errstr;
  40         const char *nt4_domain, *nt4_account;
  41
  42         struct auth_session_info *session_info;
  43
  44         NTSTATUS status;
  45
  46         DEBUG(10, ("BindSimple dn: %s\n",req->dn));
  47
  48         reply = ldapsrv_init_reply(call, LDAP_TAG_BindResponse);
  49         if (!reply) {
  50                 return NT_STATUS_NO_MEMORY;
  51         }
  52
  53         if (req->dn != NULL &&
  54             strlen(req->dn) != 0 &&
  55             call->conn->require_strong_auth > LDAP_SERVER_REQUIRE_STRONG_AUTH_NO &&
  56             call->conn->sockets.active != call->conn->sockets.tls)
  57         {
  58                 status = NT_STATUS_NETWORK_ACCESS_DENIED;
  59                 result = LDAP_STRONG_AUTH_REQUIRED;
  60                 errstr = talloc_asprintf(reply,
  61                                          "BindSimple: Transport encryption required.");
  62                 goto do_reply;
  63         }
  64
  65         status = crack_auto_name_to_nt4_name(call, call->conn->connection->event.ctx, call->conn->lp_ctx, req->dn, &nt4_domain, &nt4_account);
  66         if (NT_STATUS_IS_OK(status)) {
  67                 status = authenticate_username_pw(call,
  68                                                   call->conn->connection->event.ctx,
  69                                                   call->conn->connection->msg_ctx,
  70                                                   call->conn->lp_ctx,
  71                                                   nt4_domain, nt4_account,
  72                                                   req->creds.password,
  73                                                   MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT |
  74                                                   MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT,
  75                                                   &session_info);
  76         }
  77
  78         if (NT_STATUS_IS_OK(status)) {
  79                 result = LDAP_SUCCESS;
  80                 errstr = NULL;
  81
  82                 talloc_unlink(call->conn, call->conn->session_info);
  83                 call->conn->session_info = talloc_steal(call->conn, session_info);
  84
  85                 /* don't leak the old LDB */
  86                 talloc_unlink(call->conn, call->conn->ldb);
  87
  88                 status = ldapsrv_backend_Init(call->conn);
  89
  90                 if (!NT_STATUS_IS_OK(status)) {
  91                         result = LDAP_OPERATIONS_ERROR;
  92                         errstr = talloc_asprintf(reply, "Simple Bind: Failed to advise ldb new credentials: %s", nt_errstr(status));
  93                 }
  94         } else {
  95                 status = nt_status_squash(status);
  96
  97                 result = LDAP_INVALID_CREDENTIALS;
  98                 errstr = talloc_asprintf(reply, "Simple Bind Failed: %s", nt_errstr(status));
  99         }
 100
 101 do_reply:
 102         resp = &reply->msg->r.BindResponse;
 103         resp->response.resultcode = result;
 104         resp->response.errormessage = errstr;
 105         resp->response.dn = NULL;
 106         resp->response.referral = NULL;
 107         resp->SASL.secblob = NULL;
 108
 109         ldapsrv_queue_reply(call, reply);
 110         return NT_STATUS_OK;
 111 }
 112
 113 struct ldapsrv_sasl_postprocess_context {
 114         struct ldapsrv_connection *conn;
 115         struct tstream_context *sasl;
 116 };
 117
 118 struct ldapsrv_sasl_postprocess_state {
 119         uint8_t dummy;
 120 };
 121
 122 static struct tevent_req *ldapsrv_sasl_postprocess_send(TALLOC_CTX *mem_ctx,
 123                                                 struct tevent_context *ev,
 124                                                 void *private_data)
 125 {
 126         struct ldapsrv_sasl_postprocess_context *context =
 127                 talloc_get_type_abort(private_data,
 128                 struct ldapsrv_sasl_postprocess_context);
 129         struct tevent_req *req;
 130         struct ldapsrv_sasl_postprocess_state *state;
 131
 132         req = tevent_req_create(mem_ctx, &state,
 133                                 struct ldapsrv_sasl_postprocess_state);
 134         if (req == NULL) {
 135                 return NULL;
 136         }
 137
 138         TALLOC_FREE(context->conn->sockets.sasl);
 139         context->conn->sockets.sasl = talloc_move(context->conn, &context->sasl);
 140         context->conn->sockets.active = context->conn->sockets.sasl;
 141
 142         tevent_req_done(req);
 143         return tevent_req_post(req, ev);
 144 }
 145
 146 static NTSTATUS ldapsrv_sasl_postprocess_recv(struct tevent_req *req)
 147 {
 148         return tevent_req_simple_recv_ntstatus(req);
 149 }
 150
 151 static NTSTATUS ldapsrv_BindSASL(struct ldapsrv_call *call)
 152 {
 153         struct ldap_BindRequest *req = &call->request->r.BindRequest;
 154         struct ldapsrv_reply *reply;
 155         struct ldap_BindResponse *resp;
 156         struct ldapsrv_connection *conn;
 157         int result = 0;
 158         const char *errstr=NULL;
 159         NTSTATUS status = NT_STATUS_OK;
 160
 161         DEBUG(10, ("BindSASL dn: %s\n",req->dn));
 162
 163         reply = ldapsrv_init_reply(call, LDAP_TAG_BindResponse);
 164         if (!reply) {
 165                 return NT_STATUS_NO_MEMORY;
 166         }
 167         resp = &reply->msg->r.BindResponse;
 168
 169         conn = call->conn;
 170
 171         /*
 172          * TODO: a SASL bind with a different mechanism
 173          *       should cancel an inprogress SASL bind.
 174          *       (see RFC 4513)
 175          */
 176
 177         if (!conn->gensec) {
 178                 conn->session_info = NULL;
 179
 180                 status = samba_server_gensec_start(conn,
 181                                                    conn->connection->event.ctx,
 182                                                    conn->connection->msg_ctx,
 183                                                    conn->lp_ctx,
 184                                                    conn->server_credentials,
 185                                                    "ldap",
 186                                                    &conn->gensec);
 187                 if (!NT_STATUS_IS_OK(status)) {
 188                         DEBUG(1, ("Failed to start GENSEC server code: %s\n", nt_errstr(status)));
 189                         result = LDAP_OPERATIONS_ERROR;
 190                         errstr = talloc_asprintf(reply, "SASL: Failed to start authentication system: %s",
 191                                                  nt_errstr(status));
 192                 } else {
 193
 194                         gensec_want_feature(conn->gensec, GENSEC_FEATURE_SIGN);
 195                         gensec_want_feature(conn->gensec, GENSEC_FEATURE_SEAL);
 196                         gensec_want_feature(conn->gensec, GENSEC_FEATURE_ASYNC_REPLIES);
 197                         gensec_want_feature(conn->gensec, GENSEC_FEATURE_LDAP_STYLE);
 198
 199                         status = gensec_start_mech_by_sasl_name(conn->gensec, req->creds.SASL.mechanism);
 200
 201                         if (!NT_STATUS_IS_OK(status)) {
 202                                 DEBUG(1, ("Failed to start GENSEC SASL[%s] server code: %s\n",
 203                                           req->creds.SASL.mechanism, nt_errstr(status)));
 204                                 result = LDAP_OPERATIONS_ERROR;
 205                                 errstr = talloc_asprintf(reply, "SASL:[%s]: Failed to start authentication backend: %s",
 206                                                          req->creds.SASL.mechanism, nt_errstr(status));
 207                         }
 208                 }
 209         }
 210
 211         if (NT_STATUS_IS_OK(status)) {
 212                 DATA_BLOB input = data_blob(NULL, 0);
 213                 DATA_BLOB output = data_blob(NULL, 0);
 214
 215                 if (req->creds.SASL.secblob) {
 216                         input = *req->creds.SASL.secblob;
 217                 }
 218
 219                 status = gensec_update_ev(conn->gensec, reply, conn->connection->event.ctx,
 220                                           input, &output);
 221
 222                 /* Windows 2000 mmc doesn't like secblob == NULL and reports a decoding error */
 223                 resp->SASL.secblob = talloc(reply, DATA_BLOB);
 224                 NT_STATUS_HAVE_NO_MEMORY(resp->SASL.secblob);
 225                 *resp->SASL.secblob = output;
 226         } else {
 227                 resp->SASL.secblob = NULL;
 228         }
 229
 230         if (NT_STATUS_EQUAL(NT_STATUS_MORE_PROCESSING_REQUIRED, status)) {
 231                 result = LDAP_SASL_BIND_IN_PROGRESS;
 232                 errstr = NULL;
 233         } else if (NT_STATUS_IS_OK(status)) {
 234                 struct ldapsrv_sasl_postprocess_context *context = NULL;
 235
 236                 result = LDAP_SUCCESS;
 237                 errstr = NULL;
 238
 239                 if (gensec_have_feature(conn->gensec, GENSEC_FEATURE_SIGN) ||
 240                     gensec_have_feature(conn->gensec, GENSEC_FEATURE_SEAL)) {
 241
 242                         context = talloc(call, struct ldapsrv_sasl_postprocess_context);
 243
 244                         if (!context) {
 245                                 status = NT_STATUS_NO_MEMORY;
 246                         }
 247                 }
 248
 249                 if (context && conn->sockets.tls) {
 250                         TALLOC_FREE(context);
 251                         status = NT_STATUS_NOT_SUPPORTED;
 252                         result = LDAP_UNWILLING_TO_PERFORM;
 253                         errstr = talloc_asprintf(reply,
 254                                                  "SASL:[%s]: Sign or Seal are not allowed if TLS is used",
 255                                                  req->creds.SASL.mechanism);
 256                 }
 257
 258                 if (context && conn->sockets.sasl) {
 259                         TALLOC_FREE(context);
 260                         status = NT_STATUS_NOT_SUPPORTED;
 261                         result = LDAP_UNWILLING_TO_PERFORM;
 262                         errstr = talloc_asprintf(reply,
 263                                                  "SASL:[%s]: Sign or Seal are not allowed if SASL encryption has already been set up",
 264                                                  req->creds.SASL.mechanism);
 265                 }
 266
 267                 if (context) {
 268                         context->conn = conn;
 269                         status = gensec_create_tstream(context,
 270                                                        context->conn->gensec,
 271                                                        context->conn->sockets.raw,
 272                                                        &context->sasl);
 273                         if (NT_STATUS_IS_OK(status)) {
 274                                 if (!talloc_reference(context->sasl, conn->gensec)) {
 275                                         status = NT_STATUS_NO_MEMORY;
 276                                 }
 277                         }
 278                 } else {
 279                         switch (call->conn->require_strong_auth) {
 280                         case LDAP_SERVER_REQUIRE_STRONG_AUTH_NO:
 281                                 break;
 282                         case LDAP_SERVER_REQUIRE_STRONG_AUTH_ALLOW_SASL_OVER_TLS:
 283                                 if (call->conn->sockets.active == call->conn->sockets.tls) {
 284                                         break;
 285                                 }
 286                                 status = NT_STATUS_NETWORK_ACCESS_DENIED;
 287                                 result = LDAP_STRONG_AUTH_REQUIRED;
 288                                 errstr = talloc_asprintf(reply,
 289                                                 "SASL:[%s]: not allowed if TLS is used.",
 290                                                  req->creds.SASL.mechanism);
 291                                 break;
 292                         case LDAP_SERVER_REQUIRE_STRONG_AUTH_YES:
 293                                 status = NT_STATUS_NETWORK_ACCESS_DENIED;
 294                                 result = LDAP_STRONG_AUTH_REQUIRED;
 295                                 errstr = talloc_asprintf(reply,
 296                                                  "SASL:[%s]: Sign or Seal are required.",
 297                                                  req->creds.SASL.mechanism);
 298                                 break;
 299                         }
 300                 }
 301
 302                 if (result != LDAP_SUCCESS) {
 303                 } else if (!NT_STATUS_IS_OK(status)) {
 304                         result = LDAP_OPERATIONS_ERROR;
 305                         errstr = talloc_asprintf(reply,
 306                                                  "SASL:[%s]: Failed to setup SASL socket: %s",
 307                                                  req->creds.SASL.mechanism, nt_errstr(status));
 308                 } else {
 309                         struct auth_session_info *old_session_info=NULL;
 310
 311                         old_session_info = conn->session_info;
 312                         conn->session_info = NULL;
 313                         status = gensec_session_info(conn->gensec, conn, &conn->session_info);
 314                         if (!NT_STATUS_IS_OK(status)) {
 315                                 conn->session_info = old_session_info;
 316                                 result = LDAP_OPERATIONS_ERROR;
 317                                 errstr = talloc_asprintf(reply,
 318                                                          "SASL:[%s]: Failed to get session info: %s",
 319                                                          req->creds.SASL.mechanism, nt_errstr(status));
 320                         } else {
 321                                 talloc_unlink(conn, old_session_info);
 322
 323                                 /* don't leak the old LDB */
 324                                 talloc_unlink(conn, conn->ldb);
 325
 326                                 status = ldapsrv_backend_Init(conn);
 327
 328                                 if (!NT_STATUS_IS_OK(status)) {
 329                                         result = LDAP_OPERATIONS_ERROR;
 330                                         errstr = talloc_asprintf(reply,
 331                                                                  "SASL:[%s]: Failed to advise samdb of new credentials: %s",
 332                                                                  req->creds.SASL.mechanism,
 333                                                                  nt_errstr(status));
 334                                 }
 335                         }
 336                 }
 337
 338                 if (NT_STATUS_IS_OK(status) && context) {
 339                         call->postprocess_send = ldapsrv_sasl_postprocess_send;
 340                         call->postprocess_recv = ldapsrv_sasl_postprocess_recv;
 341                         call->postprocess_private = context;
 342                 }
 343                 talloc_unlink(conn, conn->gensec);
 344                 conn->gensec = NULL;
 345         } else {
 346                 status = nt_status_squash(status);
 347                 if (result == 0) {
 348                         result = LDAP_INVALID_CREDENTIALS;
 349                         errstr = talloc_asprintf(reply, "SASL:[%s]: %s", req->creds.SASL.mechanism, nt_errstr(status));
 350                 }
 351                 talloc_unlink(conn, conn->gensec);
 352                 conn->gensec = NULL;
 353         }
 354
 355         resp->response.resultcode = result;
 356         resp->response.dn = NULL;
 357         resp->response.errormessage = errstr;
 358         resp->response.referral = NULL;
 359
 360         ldapsrv_queue_reply(call, reply);
 361         return NT_STATUS_OK;
 362 }
 363
 364 NTSTATUS ldapsrv_BindRequest(struct ldapsrv_call *call)
 365 {
 366         struct ldap_BindRequest *req = &call->request->r.BindRequest;
 367         struct ldapsrv_reply *reply;
 368         struct ldap_BindResponse *resp;
 369
 370         if (call->conn->pending_calls != NULL) {
 371                 reply = ldapsrv_init_reply(call, LDAP_TAG_BindResponse);
 372                 if (!reply) {
 373                         return NT_STATUS_NO_MEMORY;
 374                 }
 375
 376                 resp = &reply->msg->r.BindResponse;
 377                 resp->response.resultcode = LDAP_BUSY;
 378                 resp->response.dn = NULL;
 379                 resp->response.errormessage = talloc_asprintf(reply, "Pending requests on this LDAP session");
 380                 resp->response.referral = NULL;
 381                 resp->SASL.secblob = NULL;
 382
 383                 ldapsrv_queue_reply(call, reply);
 384                 return NT_STATUS_OK;
 385         }
 386
 387         /*
 388          * TODO: a simple bind should cancel an
 389          *       inprogress SASL bind.
 390          *       (see RFC 4513)
 391          */
 392         switch (req->mechanism) {
 393                 case LDAP_AUTH_MECH_SIMPLE:
 394                         return ldapsrv_BindSimple(call);
 395                 case LDAP_AUTH_MECH_SASL:
 396                         return ldapsrv_BindSASL(call);
 397         }
 398
 399         reply = ldapsrv_init_reply(call, LDAP_TAG_BindResponse);
 400         if (!reply) {
 401                 return NT_STATUS_NO_MEMORY;
 402         }
 403
 404         resp = &reply->msg->r.BindResponse;
 405         resp->response.resultcode = LDAP_AUTH_METHOD_NOT_SUPPORTED;
 406         resp->response.dn = NULL;
 407         resp->response.errormessage = talloc_asprintf(reply, "Bad AuthenticationChoice [%d]", req->mechanism);
 408         resp->response.referral = NULL;
 409         resp->SASL.secblob = NULL;
 410
 411         ldapsrv_queue_reply(call, reply);
 412         return NT_STATUS_OK;
 413 }
 414
 415 NTSTATUS ldapsrv_UnbindRequest(struct ldapsrv_call *call)
 416 {
 417         DEBUG(10, ("UnbindRequest\n"));
 418         return NT_STATUS_OK;
 419 }