source4/librpc/rpc/dcerpc_util.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    dcerpc utility functions
   5
   6    Copyright (C) Andrew Tridgell 2003
   7    Copyright (C) Jelmer Vernooij 2004
   8    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
   9    Copyright (C) Rafal Szczesniak 2006
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "includes.h"
  26 #include "lib/events/events.h"
  27 #include "libcli/composite/composite.h"
  28 #include "librpc/gen_ndr/ndr_epmapper_c.h"
  29 #include "librpc/gen_ndr/ndr_dcerpc.h"
  30 #include "librpc/gen_ndr/ndr_misc.h"
  31 #include "librpc/rpc/dcerpc_proto.h"
  32 #include "auth/credentials/credentials.h"
  33 #include "param/param.h"
  34
  35 /*
  36   find a dcerpc call on an interface by name
  37 */
  38 const struct ndr_interface_call *dcerpc_iface_find_call(const struct ndr_interface_table *iface,
  39                                                         const char *name)
  40 {
  41         int i;
  42         for (i=0;i<iface->num_calls;i++) {
  43                 if (strcmp(iface->calls[i].name, name) == 0) {
  44                         return &iface->calls[i];
  45                 }
  46         }
  47         return NULL;
  48 }
  49
  50 /*
  51    push a ncacn_packet into a blob, potentially with auth info
  52 */
  53 NTSTATUS ncacn_push_auth(DATA_BLOB *blob, TALLOC_CTX *mem_ctx,
  54                          struct smb_iconv_convenience *iconv_convenience,
  55                          struct ncacn_packet *pkt,
  56                          struct dcerpc_auth *auth_info)
  57 {
  58         struct ndr_push *ndr;
  59         enum ndr_err_code ndr_err;
  60
  61         ndr = ndr_push_init_ctx(mem_ctx, iconv_convenience);
  62         if (!ndr) {
  63                 return NT_STATUS_NO_MEMORY;
  64         }
  65
  66         if (!(pkt->drep[0] & DCERPC_DREP_LE)) {
  67                 ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
  68         }
  69
  70         if (pkt->pfc_flags & DCERPC_PFC_FLAG_OBJECT_UUID) {
  71                 ndr->flags |= LIBNDR_FLAG_OBJECT_PRESENT;
  72         }
  73
  74         if (auth_info) {
  75                 pkt->auth_length = auth_info->credentials.length;
  76         } else {
  77                 pkt->auth_length = 0;
  78         }
  79
  80         ndr_err = ndr_push_ncacn_packet(ndr, NDR_SCALARS|NDR_BUFFERS, pkt);
  81         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  82                 return ndr_map_error2ntstatus(ndr_err);
  83         }
  84
  85         if (auth_info) {
  86 #if 0
  87                 /* the s3 rpc server doesn't handle auth padding in
  88                    bind requests. Use zero auth padding to keep us
  89                    working with old servers */
  90                 uint32_t offset = ndr->offset;
  91                 ndr_err = ndr_push_align(ndr, 16);
  92                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  93                         return ndr_map_error2ntstatus(ndr_err);
  94                 }
  95                 auth_info->auth_pad_length = ndr->offset - offset;
  96 #else
  97                 auth_info->auth_pad_length = 0;
  98 #endif
  99                 ndr_err = ndr_push_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS, auth_info);
 100                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 101                         return ndr_map_error2ntstatus(ndr_err);
 102                 }
 103         }
 104
 105         *blob = ndr_push_blob(ndr);
 106
 107         /* fill in the frag length */
 108         dcerpc_set_frag_length(blob, blob->length);
 109
 110         return NT_STATUS_OK;
 111 }
 112
 113
 114 struct epm_map_binding_state {
 115         struct dcerpc_binding *binding;
 116         const struct ndr_interface_table *table;
 117         struct dcerpc_pipe *pipe;
 118         struct policy_handle handle;
 119         struct GUID guid;
 120         struct epm_twr_t twr;
 121         struct epm_twr_t *twr_r;
 122         struct epm_Map r;
 123 };
 124
 125
 126 static void continue_epm_recv_binding(struct composite_context *ctx);
 127 static void continue_epm_map(struct tevent_req *subreq);
 128
 129
 130 /*
 131   Stage 2 of epm_map_binding: Receive connected rpc pipe and send endpoint
 132   mapping rpc request
 133 */
 134 static void continue_epm_recv_binding(struct composite_context *ctx)
 135 {
 136         struct composite_context *c = talloc_get_type(ctx->async.private_data,
 137                                                       struct composite_context);
 138         struct epm_map_binding_state *s = talloc_get_type(c->private_data,
 139                                                           struct epm_map_binding_state);
 140         struct tevent_req *subreq;
 141
 142         /* receive result of rpc pipe connect request */
 143         c->status = dcerpc_pipe_connect_b_recv(ctx, c, &s->pipe);
 144         if (!composite_is_ok(c)) return;
 145
 146         s->pipe->conn->flags |= DCERPC_NDR_REF_ALLOC;
 147
 148         /* prepare requested binding parameters */
 149         s->binding->object         = s->table->syntax_id;
 150
 151         c->status = dcerpc_binding_build_tower(s->pipe, s->binding, &s->twr.tower);
 152         if (!composite_is_ok(c)) return;
 153
 154         /* with some nice pretty paper around it of course */
 155         s->r.in.object        = &s->guid;
 156         s->r.in.map_tower     = &s->twr;
 157         s->r.in.entry_handle  = &s->handle;
 158         s->r.in.max_towers    = 1;
 159         s->r.out.entry_handle = &s->handle;
 160
 161         /* send request for an endpoint mapping - a rpc request on connected pipe */
 162         subreq = dcerpc_epm_Map_r_send(s, c->event_ctx,
 163                                        s->pipe->binding_handle,
 164                                        &s->r);
 165         if (composite_nomem(subreq, c)) return;
 166
 167         tevent_req_set_callback(subreq, continue_epm_map, c);
 168 }
 169
 170
 171 /*
 172   Stage 3 of epm_map_binding: Receive endpoint mapping and provide binding details
 173 */
 174 static void continue_epm_map(struct tevent_req *subreq)
 175 {
 176         struct composite_context *c = tevent_req_callback_data(subreq,
 177                                       struct composite_context);
 178         struct epm_map_binding_state *s = talloc_get_type(c->private_data,
 179                                                           struct epm_map_binding_state);
 180
 181         /* receive result of a rpc request */
 182         c->status = dcerpc_epm_Map_r_recv(subreq, s);
 183         TALLOC_FREE(subreq);
 184         if (!composite_is_ok(c)) return;
 185
 186         /* check the details */
 187         if (s->r.out.result != 0 || *s->r.out.num_towers != 1) {
 188                 composite_error(c, NT_STATUS_PORT_UNREACHABLE);
 189                 return;
 190         }
 191
 192         s->twr_r = s->r.out.towers[0].twr;
 193         if (s->twr_r == NULL) {
 194                 composite_error(c, NT_STATUS_PORT_UNREACHABLE);
 195                 return;
 196         }
 197
 198         if (s->twr_r->tower.num_floors != s->twr.tower.num_floors ||
 199             s->twr_r->tower.floors[3].lhs.protocol != s->twr.tower.floors[3].lhs.protocol) {
 200                 composite_error(c, NT_STATUS_PORT_UNREACHABLE);
 201                 return;
 202         }
 203
 204         /* get received endpoint */
 205         s->binding->endpoint = talloc_reference(s->binding,
 206                                                 dcerpc_floor_get_rhs_data(c, &s->twr_r->tower.floors[3]));
 207         if (composite_nomem(s->binding->endpoint, c)) return;
 208
 209         composite_done(c);
 210 }
 211
 212
 213 /*
 214   Request for endpoint mapping of dcerpc binding - try to request for endpoint
 215   unless there is default one.
 216 */
 217 struct composite_context *dcerpc_epm_map_binding_send(TALLOC_CTX *mem_ctx,
 218                                                       struct dcerpc_binding *binding,
 219                                                       const struct ndr_interface_table *table,
 220                                                       struct tevent_context *ev,
 221                                                       struct loadparm_context *lp_ctx)
 222 {
 223         struct composite_context *c;
 224         struct epm_map_binding_state *s;
 225         struct composite_context *pipe_connect_req;
 226         struct cli_credentials *anon_creds;
 227
 228         NTSTATUS status;
 229         struct dcerpc_binding *epmapper_binding;
 230         int i;
 231
 232         if (ev == NULL) {
 233                 return NULL;
 234         }
 235
 236         /* composite context allocation and setup */
 237         c = composite_create(mem_ctx, ev);
 238         if (c == NULL) {
 239                 return NULL;
 240         }
 241
 242         s = talloc_zero(c, struct epm_map_binding_state);
 243         if (composite_nomem(s, c)) return c;
 244         c->private_data = s;
 245
 246         s->binding = binding;
 247         s->table   = table;
 248
 249         /* anonymous credentials for rpc connection used to get endpoint mapping */
 250         anon_creds = cli_credentials_init(mem_ctx);
 251         cli_credentials_set_anonymous(anon_creds);
 252
 253         /*
 254           First, check if there is a default endpoint specified in the IDL
 255         */
 256         if (table != NULL) {
 257                 struct dcerpc_binding *default_binding;
 258
 259                 /* Find one of the default pipes for this interface */
 260                 for (i = 0; i < table->endpoints->count; i++) {
 261                         status = dcerpc_parse_binding(mem_ctx, table->endpoints->names[i], &default_binding);
 262
 263                         if (NT_STATUS_IS_OK(status)) {
 264                                 if (binding->transport == NCA_UNKNOWN)
 265                                         binding->transport = default_binding->transport;
 266                                 if (default_binding->transport == binding->transport &&
 267                                         default_binding->endpoint) {
 268                                         binding->endpoint = talloc_reference(binding, default_binding->endpoint);
 269                                         talloc_free(default_binding);
 270
 271                                         composite_done(c);
 272                                         return c;
 273
 274                                 } else {
 275                                         talloc_free(default_binding);
 276                                 }
 277                         }
 278                 }
 279         }
 280
 281         epmapper_binding = talloc_zero(c, struct dcerpc_binding);
 282         if (composite_nomem(epmapper_binding, c)) return c;
 283
 284         /* basic endpoint mapping data */
 285         epmapper_binding->transport             = binding->transport;
 286         epmapper_binding->host                  = talloc_reference(epmapper_binding, binding->host);
 287         epmapper_binding->target_hostname       = epmapper_binding->host;
 288         epmapper_binding->options               = NULL;
 289         epmapper_binding->flags                 = 0;
 290         epmapper_binding->assoc_group_id        = 0;
 291         epmapper_binding->endpoint              = NULL;
 292
 293         /* initiate rpc pipe connection */
 294         pipe_connect_req = dcerpc_pipe_connect_b_send(c, epmapper_binding,
 295                                                       &ndr_table_epmapper,
 296                                                       anon_creds, c->event_ctx,
 297                                                       lp_ctx);
 298         if (composite_nomem(pipe_connect_req, c)) return c;
 299
 300         composite_continue(c, pipe_connect_req, continue_epm_recv_binding, c);
 301         return c;
 302 }
 303
 304
 305 /*
 306   Receive result of endpoint mapping request
 307  */
 308 NTSTATUS dcerpc_epm_map_binding_recv(struct composite_context *c)
 309 {
 310         NTSTATUS status = composite_wait(c);
 311
 312         talloc_free(c);
 313         return status;
 314 }
 315
 316
 317 /*
 318   Get endpoint mapping for rpc connection
 319 */
 320 _PUBLIC_ NTSTATUS dcerpc_epm_map_binding(TALLOC_CTX *mem_ctx, struct dcerpc_binding *binding,
 321                                 const struct ndr_interface_table *table, struct tevent_context *ev,
 322                                 struct loadparm_context *lp_ctx)
 323 {
 324         struct composite_context *c;
 325
 326         c = dcerpc_epm_map_binding_send(mem_ctx, binding, table, ev, lp_ctx);
 327         return dcerpc_epm_map_binding_recv(c);
 328 }
 329
 330
 331 struct pipe_auth_state {
 332         struct dcerpc_pipe *pipe;
 333         struct dcerpc_binding *binding;
 334         const struct ndr_interface_table *table;
 335         struct loadparm_context *lp_ctx;
 336         struct cli_credentials *credentials;
 337 };
 338
 339
 340 static void continue_auth_schannel(struct composite_context *ctx);
 341 static void continue_auth(struct composite_context *ctx);
 342 static void continue_auth_none(struct composite_context *ctx);
 343 static void continue_ntlmssp_connection(struct composite_context *ctx);
 344 static void continue_spnego_after_wrong_pass(struct composite_context *ctx);
 345
 346
 347 /*
 348   Stage 2 of pipe_auth: Receive result of schannel bind request
 349 */
 350 static void continue_auth_schannel(struct composite_context *ctx)
 351 {
 352         struct composite_context *c = talloc_get_type(ctx->async.private_data,
 353                                                       struct composite_context);
 354
 355         c->status = dcerpc_bind_auth_schannel_recv(ctx);
 356         if (!composite_is_ok(c)) return;
 357
 358         composite_done(c);
 359 }
 360
 361
 362 /*
 363   Stage 2 of pipe_auth: Receive result of authenticated bind request
 364 */
 365 static void continue_auth(struct composite_context *ctx)
 366 {
 367         struct composite_context *c = talloc_get_type(ctx->async.private_data,
 368                                                       struct composite_context);
 369
 370         c->status = dcerpc_bind_auth_recv(ctx);
 371         if (!composite_is_ok(c)) return;
 372
 373         composite_done(c);
 374 }
 375 /*
 376   Stage 2 of pipe_auth: Receive result of authenticated bind request, but handle fallbacks:
 377   SPNEGO -> NTLMSSP
 378 */
 379 static void continue_auth_auto(struct composite_context *ctx)
 380 {
 381         struct composite_context *c = talloc_get_type(ctx->async.private_data,
 382                                                       struct composite_context);
 383         struct pipe_auth_state *s = talloc_get_type(c->private_data, struct pipe_auth_state);
 384         struct composite_context *sec_conn_req;
 385
 386         c->status = dcerpc_bind_auth_recv(ctx);
 387         if (NT_STATUS_EQUAL(c->status, NT_STATUS_INVALID_PARAMETER)) {
 388                 /*
 389                  * Retry with NTLMSSP auth as fallback
 390                  * send a request for secondary rpc connection
 391                  */
 392                 sec_conn_req = dcerpc_secondary_connection_send(s->pipe,
 393                                                                 s->binding);
 394                 composite_continue(c, sec_conn_req, continue_ntlmssp_connection, c);
 395                 return;
 396         } else if (NT_STATUS_EQUAL(c->status, NT_STATUS_LOGON_FAILURE)) {
 397                 if (cli_credentials_wrong_password(s->credentials)) {
 398                         /*
 399                          * Retry SPNEGO with a better password
 400                          * send a request for secondary rpc connection
 401                          */
 402                         sec_conn_req = dcerpc_secondary_connection_send(s->pipe,
 403                                                                         s->binding);
 404                         composite_continue(c, sec_conn_req, continue_spnego_after_wrong_pass, c);
 405                         return;
 406                 }
 407         }
 408
 409         if (!composite_is_ok(c)) return;
 410
 411         composite_done(c);
 412 }
 413
 414 /*
 415   Stage 3 of pipe_auth (fallback to NTLMSSP case): Receive secondary
 416   rpc connection (the first one can't be used any more, due to the
 417   bind nak) and perform authenticated bind request
 418 */
 419 static void continue_ntlmssp_connection(struct composite_context *ctx)
 420 {
 421         struct composite_context *c;
 422         struct pipe_auth_state *s;
 423         struct composite_context *auth_req;
 424         struct dcerpc_pipe *p2;
 425
 426         c = talloc_get_type(ctx->async.private_data, struct composite_context);
 427         s = talloc_get_type(c->private_data, struct pipe_auth_state);
 428
 429         /* receive secondary rpc connection */
 430         c->status = dcerpc_secondary_connection_recv(ctx, &p2);
 431         if (!composite_is_ok(c)) return;
 432
 433         talloc_steal(s, p2);
 434         talloc_steal(p2, s->pipe);
 435         s->pipe = p2;
 436
 437         /* initiate a authenticated bind */
 438         auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table,
 439                                          s->credentials,
 440                                          lp_gensec_settings(c, s->lp_ctx),
 441                                          DCERPC_AUTH_TYPE_NTLMSSP,
 442                                          dcerpc_auth_level(s->pipe->conn),
 443                                          s->table->authservices->names[0]);
 444         composite_continue(c, auth_req, continue_auth, c);
 445 }
 446
 447 /*
 448   Stage 3 of pipe_auth (retry on wrong password): Receive secondary
 449   rpc connection (the first one can't be used any more, due to the
 450   bind nak) and perform authenticated bind request
 451 */
 452 static void continue_spnego_after_wrong_pass(struct composite_context *ctx)
 453 {
 454         struct composite_context *c;
 455         struct pipe_auth_state *s;
 456         struct composite_context *auth_req;
 457         struct dcerpc_pipe *p2;
 458
 459         c = talloc_get_type(ctx->async.private_data, struct composite_context);
 460         s = talloc_get_type(c->private_data, struct pipe_auth_state);
 461
 462         /* receive secondary rpc connection */
 463         c->status = dcerpc_secondary_connection_recv(ctx, &p2);
 464         if (!composite_is_ok(c)) return;
 465
 466         talloc_steal(s, p2);
 467         talloc_steal(p2, s->pipe);
 468         s->pipe = p2;
 469
 470         /* initiate a authenticated bind */
 471         auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table,
 472                                          s->credentials,
 473                                          lp_gensec_settings(c, s->lp_ctx),
 474                                          DCERPC_AUTH_TYPE_SPNEGO,
 475                                          dcerpc_auth_level(s->pipe->conn),
 476                                          s->table->authservices->names[0]);
 477         composite_continue(c, auth_req, continue_auth, c);
 478 }
 479
 480
 481 /*
 482   Stage 2 of pipe_auth: Receive result of non-authenticated bind request
 483 */
 484 static void continue_auth_none(struct composite_context *ctx)
 485 {
 486         struct composite_context *c = talloc_get_type(ctx->async.private_data,
 487                                                       struct composite_context);
 488
 489         c->status = dcerpc_bind_auth_none_recv(ctx);
 490         if (!composite_is_ok(c)) return;
 491
 492         composite_done(c);
 493 }
 494
 495
 496 /*
 497   Request to perform an authenticated bind if required. Authentication
 498   is determined using credentials passed and binding flags.
 499 */
 500 struct composite_context *dcerpc_pipe_auth_send(struct dcerpc_pipe *p,
 501                                                 struct dcerpc_binding *binding,
 502                                                 const struct ndr_interface_table *table,
 503                                                 struct cli_credentials *credentials,
 504                                                 struct loadparm_context *lp_ctx)
 505 {
 506         struct composite_context *c;
 507         struct pipe_auth_state *s;
 508         struct composite_context *auth_schannel_req;
 509         struct composite_context *auth_req;
 510         struct composite_context *auth_none_req;
 511         struct dcerpc_connection *conn;
 512         uint8_t auth_type;
 513
 514         /* composite context allocation and setup */
 515         c = composite_create(p, p->conn->event_ctx);
 516         if (c == NULL) return NULL;
 517
 518         s = talloc_zero(c, struct pipe_auth_state);
 519         if (composite_nomem(s, c)) return c;
 520         c->private_data = s;
 521
 522         /* store parameters in state structure */
 523         s->binding      = binding;
 524         s->table        = table;
 525         s->credentials  = credentials;
 526         s->pipe         = p;
 527         s->lp_ctx       = lp_ctx;
 528
 529         conn = s->pipe->conn;
 530         conn->flags = binding->flags;
 531
 532         if (DEBUGLVL(100)) {
 533                 conn->flags |= DCERPC_DEBUG_PRINT_BOTH;
 534         }
 535
 536         /* remember the binding string for possible secondary connections */
 537         conn->binding_string = dcerpc_binding_string(p, binding);
 538
 539         if (cli_credentials_is_anonymous(s->credentials)) {
 540                 auth_none_req = dcerpc_bind_auth_none_send(c, s->pipe, s->table);
 541                 composite_continue(c, auth_none_req, continue_auth_none, c);
 542                 return c;
 543         }
 544
 545         if ((binding->flags & DCERPC_SCHANNEL) &&
 546             !cli_credentials_get_netlogon_creds(s->credentials)) {
 547                 /* If we don't already have netlogon credentials for
 548                  * the schannel bind, then we have to get these
 549                  * first */
 550                 auth_schannel_req = dcerpc_bind_auth_schannel_send(c, s->pipe, s->table,
 551                                                                    s->credentials, s->lp_ctx,
 552                                                                    dcerpc_auth_level(conn));
 553                 composite_continue(c, auth_schannel_req, continue_auth_schannel, c);
 554                 return c;
 555         }
 556
 557         /*
 558          * we rely on the already authenticated CIFS connection
 559          * if not doing sign or seal
 560          */
 561         if (conn->transport.transport == NCACN_NP &&
 562             !(s->binding->flags & (DCERPC_SIGN|DCERPC_SEAL))) {
 563                 auth_none_req = dcerpc_bind_auth_none_send(c, s->pipe, s->table);
 564                 composite_continue(c, auth_none_req, continue_auth_none, c);
 565                 return c;
 566         }
 567
 568
 569         /* Perform an authenticated DCE-RPC bind
 570          */
 571         if (!(conn->flags & (DCERPC_SIGN|DCERPC_SEAL))) {
 572                 /*
 573                   we are doing an authenticated connection,
 574                   but not using sign or seal. We must force
 575                   the CONNECT dcerpc auth type as a NONE auth
 576                   type doesn't allow authentication
 577                   information to be passed.
 578                 */
 579                 conn->flags |= DCERPC_CONNECT;
 580         }
 581
 582         if (s->binding->flags & DCERPC_AUTH_SPNEGO) {
 583                 auth_type = DCERPC_AUTH_TYPE_SPNEGO;
 584
 585         } else if (s->binding->flags & DCERPC_AUTH_KRB5) {
 586                 auth_type = DCERPC_AUTH_TYPE_KRB5;
 587
 588         } else if (s->binding->flags & DCERPC_SCHANNEL) {
 589                 auth_type = DCERPC_AUTH_TYPE_SCHANNEL;
 590
 591         } else if (s->binding->flags & DCERPC_AUTH_NTLM) {
 592                 auth_type = DCERPC_AUTH_TYPE_NTLMSSP;
 593
 594         } else {
 595                 /* try SPNEGO with fallback to NTLMSSP */
 596                 auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table,
 597                                                  s->credentials,
 598                                                  lp_gensec_settings(c, s->lp_ctx),
 599                                                  DCERPC_AUTH_TYPE_SPNEGO,
 600                                                  dcerpc_auth_level(conn),
 601                                                  s->table->authservices->names[0]);
 602                 composite_continue(c, auth_req, continue_auth_auto, c);
 603                 return c;
 604         }
 605
 606         auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table,
 607                                          s->credentials,
 608                                          lp_gensec_settings(c, s->lp_ctx),
 609                                          auth_type,
 610                                          dcerpc_auth_level(conn),
 611                                          s->table->authservices->names[0]);
 612         composite_continue(c, auth_req, continue_auth, c);
 613         return c;
 614 }
 615
 616
 617 /*
 618   Receive result of authenticated bind request on dcerpc pipe
 619
 620   This returns *p, which may be different to the one originally
 621   supllied, as it rebinds to a new pipe due to authentication fallback
 622
 623 */
 624 NTSTATUS dcerpc_pipe_auth_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
 625                                struct dcerpc_pipe **p)
 626 {
 627         NTSTATUS status;
 628
 629         struct pipe_auth_state *s = talloc_get_type(c->private_data,
 630                                                     struct pipe_auth_state);
 631         status = composite_wait(c);
 632         if (!NT_STATUS_IS_OK(status)) {
 633                 char *uuid_str = GUID_string(s->pipe, &s->table->syntax_id.uuid);
 634                 DEBUG(0, ("Failed to bind to uuid %s - %s\n", uuid_str, nt_errstr(status)));
 635                 talloc_free(uuid_str);
 636         } else {
 637                 talloc_steal(mem_ctx, s->pipe);
 638                 *p = s->pipe;
 639         }
 640
 641         talloc_free(c);
 642         return status;
 643 }
 644
 645
 646 /*
 647    Perform an authenticated bind if needed - sync version
 648
 649    This may change *p, as it rebinds to a new pipe due to authentication fallback
 650 */
 651 _PUBLIC_ NTSTATUS dcerpc_pipe_auth(TALLOC_CTX *mem_ctx,
 652                           struct dcerpc_pipe **p,
 653                           struct dcerpc_binding *binding,
 654                           const struct ndr_interface_table *table,
 655                           struct cli_credentials *credentials,
 656                           struct loadparm_context *lp_ctx)
 657 {
 658         struct composite_context *c;
 659
 660         c = dcerpc_pipe_auth_send(*p, binding, table, credentials, lp_ctx);
 661         return dcerpc_pipe_auth_recv(c, mem_ctx, p);
 662 }
 663
 664
 665 NTSTATUS dcerpc_generic_session_key(struct dcerpc_connection *c,
 666                                     DATA_BLOB *session_key)
 667 {
 668         /* this took quite a few CPU cycles to find ... */
 669         session_key->data = discard_const_p(unsigned char, "SystemLibraryDTC");
 670         session_key->length = 16;
 671         return NT_STATUS_OK;
 672 }
 673
 674 /*
 675   fetch the user session key - may be default (above) or the SMB session key
 676
 677   The key is always truncated to 16 bytes
 678 */
 679 _PUBLIC_ NTSTATUS dcerpc_fetch_session_key(struct dcerpc_pipe *p,
 680                                            DATA_BLOB *session_key)
 681 {
 682         NTSTATUS status;
 683         status = p->conn->security_state.session_key(p->conn, session_key);
 684         if (!NT_STATUS_IS_OK(status)) {
 685                 return status;
 686         }
 687
 688         session_key->length = MIN(session_key->length, 16);
 689
 690         return NT_STATUS_OK;
 691 }
 692
 693
 694 /*
 695   log a rpc packet in a format suitable for ndrdump. This is especially useful
 696   for sealed packets, where ethereal cannot easily see the contents
 697
 698   this triggers on a debug level of >= 10
 699 */
 700 _PUBLIC_ void dcerpc_log_packet(const char *lockdir,
 701                                                                 const struct ndr_interface_table *ndr,
 702                        uint32_t opnum, uint32_t flags,
 703                        DATA_BLOB *pkt)
 704 {
 705         const int num_examples = 20;
 706         int i;
 707
 708         if (lockdir == NULL) return;
 709
 710         for (i=0;i<num_examples;i++) {
 711                 char *name=NULL;
 712                 asprintf(&name, "%s/rpclog/%s-%u.%d.%s",
 713                          lockdir, ndr->name, opnum, i,
 714                          (flags&NDR_IN)?"in":"out");
 715                 if (name == NULL) {
 716                         return;
 717                 }
 718                 if (!file_exist(name)) {
 719                         if (file_save(name, pkt->data, pkt->length)) {
 720                                 DEBUG(10,("Logged rpc packet to %s\n", name));
 721                         }
 722                         free(name);
 723                         break;
 724                 }
 725                 free(name);
 726         }
 727 }
 728
 729
 730
 731 /*
 732   create a secondary context from a primary connection
 733
 734   this uses dcerpc_alter_context() to create a new dcerpc context_id
 735 */
 736 _PUBLIC_ NTSTATUS dcerpc_secondary_context(struct dcerpc_pipe *p,
 737                                   struct dcerpc_pipe **pp2,
 738                                   const struct ndr_interface_table *table)
 739 {
 740         NTSTATUS status;
 741         struct dcerpc_pipe *p2;
 742
 743         p2 = talloc_zero(p, struct dcerpc_pipe);
 744         if (p2 == NULL) {
 745                 return NT_STATUS_NO_MEMORY;
 746         }
 747         p2->conn = talloc_reference(p2, p->conn);
 748         p2->request_timeout = p->request_timeout;
 749
 750         p2->context_id = ++p->conn->next_context_id;
 751
 752         p2->syntax = table->syntax_id;
 753
 754         p2->transfer_syntax = p->transfer_syntax;
 755
 756         p2->binding = talloc_reference(p2, p->binding);
 757
 758         status = dcerpc_alter_context(p2, p2, &p2->syntax, &p2->transfer_syntax);
 759         if (!NT_STATUS_IS_OK(status)) {
 760                 talloc_free(p2);
 761                 return status;
 762         }
 763
 764         *pp2 = p2;
 765
 766         return NT_STATUS_OK;
 767 }
 768
 769
 770 /*
 771   pull an dcerpc_auth structure, taking account of any auth padding in
 772   the blob at the end of the structure
 773  */
 774 NTSTATUS dcerpc_pull_auth_trailer(struct ncacn_packet *pkt,
 775                                   TALLOC_CTX *mem_ctx,
 776                                   DATA_BLOB *pkt_auth_blob,
 777                                   struct dcerpc_auth *auth,
 778                                   uint32_t *auth_length,
 779                                   bool check_pad)
 780 {
 781         struct ndr_pull *ndr;
 782         enum ndr_err_code ndr_err;
 783         uint32_t pad;
 784
 785         pad = pkt_auth_blob->length - (DCERPC_AUTH_TRAILER_LENGTH + pkt->auth_length);
 786
 787         /* paranoia check for pad size. This would be caught anyway by
 788            the ndr_pull_advance() a few lines down, but it scared
 789            Jeremy enough for him to call me, so we might as well check
 790            it now, just to prevent someone posting a bogus YouTube
 791            video in the future.
 792         */
 793         if (pad > pkt_auth_blob->length) {
 794                 return NT_STATUS_INFO_LENGTH_MISMATCH;
 795         }
 796
 797         *auth_length = pkt_auth_blob->length - pad;
 798
 799         ndr = ndr_pull_init_blob(pkt_auth_blob, mem_ctx, NULL);
 800         if (!ndr) {
 801                 return NT_STATUS_NO_MEMORY;
 802         }
 803
 804         if (!(pkt->drep[0] & DCERPC_DREP_LE)) {
 805                 ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
 806         }
 807
 808         ndr_err = ndr_pull_advance(ndr, pad);
 809         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 810                 talloc_free(ndr);
 811                 return ndr_map_error2ntstatus(ndr_err);
 812         }
 813
 814         ndr_err = ndr_pull_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS, auth);
 815         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 816                 talloc_free(ndr);
 817                 return ndr_map_error2ntstatus(ndr_err);
 818         }
 819
 820         if (check_pad && pad != auth->auth_pad_length) {
 821                 DEBUG(1,(__location__ ": WARNING: pad length mismatch. Calculated %u  got %u\n",
 822                          (unsigned)pad, (unsigned)auth->auth_pad_length));
 823         }
 824
 825         DEBUG(6,(__location__ ": auth_pad_length %u\n",
 826                  (unsigned)auth->auth_pad_length));
 827
 828         talloc_steal(mem_ctx, auth->credentials.data);
 829         talloc_free(ndr);
 830
 831         return NT_STATUS_OK;
 832 }
 833
 834