source/librpc/rpc/dcerpc_smb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    dcerpc over SMB transport
   5
   6    Copyright (C) Tim Potter 2003
   7    Copyright (C) Andrew Tridgell 2003
   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 2 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, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 */
  23
  24 #include "includes.h"
  25 #include "libcli/raw/libcliraw.h"
  26 #include "libcli/composite/composite.h"
  27 #include "librpc/rpc/dcerpc.h"
  28
  29 /* transport private information used by SMB pipe transport */
  30 struct smb_private {
  31         uint16_t fnum;
  32         struct smbcli_tree *tree;
  33         const char *server_name;
  34 };
  35
  36
  37 /*
  38   tell the dcerpc layer that the transport is dead
  39 */
  40 static void pipe_dead(struct dcerpc_connection *c, NTSTATUS status)
  41 {
  42         c->transport.recv_data(c, NULL, status);
  43 }
  44
  45
  46 /*
  47    this holds the state of an in-flight call
  48 */
  49 struct smb_read_state {
  50         struct dcerpc_connection *c;
  51         struct smbcli_request *req;
  52         size_t received;
  53         DATA_BLOB data;
  54         union smb_read *io;
  55 };
  56
  57 /*
  58   called when a read request has completed
  59 */
  60 static void smb_read_callback(struct smbcli_request *req)
  61 {
  62         struct smb_private *smb;
  63         struct smb_read_state *state;
  64         union smb_read *io;
  65         uint16_t frag_length;
  66         NTSTATUS status;
  67
  68         state = talloc_get_type(req->async.private, struct smb_read_state);
  69         smb = talloc_get_type(state->c->transport.private, struct smb_private);
  70         io = state->io;
  71
  72         status = smb_raw_read_recv(state->req, io);
  73         if (NT_STATUS_IS_ERR(status)) {
  74                 pipe_dead(state->c, status);
  75                 talloc_free(state);
  76                 return;
  77         }
  78
  79         state->received += io->readx.out.nread;
  80
  81         if (state->received < 16) {
  82                 DEBUG(0,("dcerpc_smb: short packet (length %d) in read callback!\n",
  83                          (int)state->received));
  84                 pipe_dead(state->c, NT_STATUS_INFO_LENGTH_MISMATCH);
  85                 talloc_free(state);
  86                 return;
  87         }
  88
  89         frag_length = dcerpc_get_frag_length(&state->data);
  90
  91         if (frag_length <= state->received) {
  92                 DATA_BLOB data = state->data;
  93                 struct dcerpc_connection *c = state->c;
  94                 data.length = state->received;
  95                 talloc_steal(state->c, data.data);
  96                 talloc_free(state);
  97                 c->transport.recv_data(c, &data, NT_STATUS_OK);
  98                 return;
  99         }
 100
 101         /* initiate another read request, as we only got part of a fragment */
 102         state->data.data = talloc_realloc(state, state->data.data, uint8_t, frag_length);
 103
 104         io->readx.in.mincnt = MIN(state->c->srv_max_xmit_frag,
 105                                   frag_length - state->received);
 106         io->readx.in.maxcnt = io->readx.in.mincnt;
 107         io->readx.out.data = state->data.data + state->received;
 108
 109         state->req = smb_raw_read_send(smb->tree, io);
 110         if (state->req == NULL) {
 111                 pipe_dead(state->c, NT_STATUS_NO_MEMORY);
 112                 talloc_free(state);
 113                 return;
 114         }
 115
 116         state->req->async.fn = smb_read_callback;
 117         state->req->async.private = state;
 118 }
 119
 120 /*
 121   trigger a read request from the server, possibly with some initial
 122   data in the read buffer
 123 */
 124 static NTSTATUS send_read_request_continue(struct dcerpc_connection *c, DATA_BLOB *blob)
 125 {
 126         struct smb_private *smb = c->transport.private;
 127         union smb_read *io;
 128         struct smb_read_state *state;
 129         struct smbcli_request *req;
 130
 131         state = talloc(smb, struct smb_read_state);
 132         if (state == NULL) {
 133                 return NT_STATUS_NO_MEMORY;
 134         }
 135
 136         state->c = c;
 137         if (blob == NULL) {
 138                 state->received = 0;
 139                 state->data = data_blob_talloc(state, NULL, 0x2000);
 140         } else {
 141                 uint32_t frag_length = blob->length>=16?
 142                         dcerpc_get_frag_length(blob):0x2000;
 143                 state->received = blob->length;
 144                 state->data = data_blob_talloc(state, NULL, frag_length);
 145                 if (!state->data.data) {
 146                         talloc_free(state);
 147                         return NT_STATUS_NO_MEMORY;
 148                 }
 149                 memcpy(state->data.data, blob->data, blob->length);
 150         }
 151
 152         state->io = talloc(state, union smb_read);
 153
 154         io = state->io;
 155         io->generic.level = RAW_READ_READX;
 156         io->readx.in.file.fnum = smb->fnum;
 157         io->readx.in.mincnt = state->data.length - state->received;
 158         io->readx.in.maxcnt = io->readx.in.mincnt;
 159         io->readx.in.offset = 0;
 160         io->readx.in.remaining = 0;
 161         io->readx.in.read_for_execute = False;
 162         io->readx.out.data = state->data.data + state->received;
 163         req = smb_raw_read_send(smb->tree, io);
 164         if (req == NULL) {
 165                 return NT_STATUS_NO_MEMORY;
 166         }
 167
 168         req->async.fn = smb_read_callback;
 169         req->async.private = state;
 170
 171         state->req = req;
 172
 173         return NT_STATUS_OK;
 174 }
 175
 176
 177 /*
 178   trigger a read request from the server
 179 */
 180 static NTSTATUS send_read_request(struct dcerpc_connection *c)
 181 {
 182         return send_read_request_continue(c, NULL);
 183 }
 184
 185 /*
 186    this holds the state of an in-flight trans call
 187 */
 188 struct smb_trans_state {
 189         struct dcerpc_connection *c;
 190         struct smbcli_request *req;
 191         struct smb_trans2 *trans;
 192 };
 193
 194 /*
 195   called when a trans request has completed
 196 */
 197 static void smb_trans_callback(struct smbcli_request *req)
 198 {
 199         struct smb_trans_state *state = req->async.private;
 200         struct dcerpc_connection *c = state->c;
 201         NTSTATUS status;
 202
 203         status = smb_raw_trans_recv(req, state, state->trans);
 204
 205         if (NT_STATUS_IS_ERR(status)) {
 206                 pipe_dead(c, status);
 207                 return;
 208         }
 209
 210         if (!NT_STATUS_EQUAL(status, STATUS_BUFFER_OVERFLOW)) {
 211                 DATA_BLOB data = state->trans->out.data;
 212                 talloc_steal(c, data.data);
 213                 talloc_free(state);
 214                 c->transport.recv_data(c, &data, NT_STATUS_OK);
 215                 return;
 216         }
 217
 218         /* there is more to receive - setup a readx */
 219         send_read_request_continue(c, &state->trans->out.data);
 220         talloc_free(state);
 221 }
 222
 223 /*
 224   send a SMBtrans style request
 225 */
 226 static NTSTATUS smb_send_trans_request(struct dcerpc_connection *c, DATA_BLOB *blob)
 227 {
 228         struct smb_private *smb = c->transport.private;
 229         struct smb_trans2 *trans;
 230         uint16_t setup[2];
 231         struct smb_trans_state *state;
 232
 233         state = talloc(smb, struct smb_trans_state);
 234         if (state == NULL) {
 235                 return NT_STATUS_NO_MEMORY;
 236         }
 237
 238         state->c = c;
 239         state->trans = talloc(state, struct smb_trans2);
 240         trans = state->trans;
 241
 242         trans->in.data = *blob;
 243         trans->in.params = data_blob(NULL, 0);
 244
 245         setup[0] = TRANSACT_DCERPCCMD;
 246         setup[1] = smb->fnum;
 247
 248         trans->in.max_param = 0;
 249         trans->in.max_data = smb_raw_max_trans_data(smb->tree, 0);
 250         trans->in.max_setup = 0;
 251         trans->in.setup_count = 2;
 252         trans->in.flags = 0;
 253         trans->in.timeout = 0;
 254         trans->in.setup = setup;
 255         trans->in.trans_name = "\\PIPE\\";
 256
 257         state->req = smb_raw_trans_send(smb->tree, trans);
 258         if (state->req == NULL) {
 259                 talloc_free(state);
 260                 return NT_STATUS_NO_MEMORY;
 261         }
 262
 263         state->req->async.fn = smb_trans_callback;
 264         state->req->async.private = state;
 265
 266         talloc_steal(state, state->req);
 267
 268         return NT_STATUS_OK;
 269 }
 270
 271 /*
 272   called when a write request has completed
 273 */
 274 static void smb_write_callback(struct smbcli_request *req)
 275 {
 276         struct dcerpc_connection *c = req->async.private;
 277
 278         if (!NT_STATUS_IS_OK(req->status)) {
 279                 DEBUG(0,("dcerpc_smb: write callback error\n"));
 280                 pipe_dead(c, req->status);
 281         }
 282
 283         smbcli_request_destroy(req);
 284 }
 285
 286 /*
 287    send a packet to the server
 288 */
 289 static NTSTATUS smb_send_request(struct dcerpc_connection *c, DATA_BLOB *blob, BOOL trigger_read)
 290 {
 291         struct smb_private *smb = c->transport.private;
 292         union smb_write io;
 293         struct smbcli_request *req;
 294
 295         if (trigger_read) {
 296                 return smb_send_trans_request(c, blob);
 297         }
 298
 299         io.generic.level = RAW_WRITE_WRITEX;
 300         io.writex.in.file.fnum = smb->fnum;
 301         io.writex.in.offset = 0;
 302         io.writex.in.wmode = PIPE_START_MESSAGE;
 303         io.writex.in.remaining = blob->length;
 304         io.writex.in.count = blob->length;
 305         io.writex.in.data = blob->data;
 306
 307         /* we must not timeout at the smb level for rpc requests, as otherwise
 308            signing/sealing can be messed up */
 309         smb->tree->session->transport->options.request_timeout = 0;
 310
 311         req = smb_raw_write_send(smb->tree, &io);
 312         if (req == NULL) {
 313                 return NT_STATUS_NO_MEMORY;
 314         }
 315
 316         req->async.fn = smb_write_callback;
 317         req->async.private = c;
 318
 319         if (trigger_read) {
 320                 send_read_request(c);
 321         }
 322
 323         return NT_STATUS_OK;
 324 }
 325
 326 /*
 327    shutdown SMB pipe connection
 328 */
 329 static NTSTATUS smb_shutdown_pipe(struct dcerpc_connection *c)
 330 {
 331         struct smb_private *smb = c->transport.private;
 332         union smb_close io;
 333         struct smbcli_request *req;
 334
 335         /* maybe we're still starting up */
 336         if (!smb) return NT_STATUS_OK;
 337
 338         io.close.level = RAW_CLOSE_CLOSE;
 339         io.close.in.file.fnum = smb->fnum;
 340         io.close.in.write_time = 0;
 341         req = smb_raw_close_send(smb->tree, &io);
 342         if (req != NULL) {
 343                 /* we don't care if this fails, so just free it if it succeeds */
 344                 req->async.fn = (void (*)(struct smbcli_request *))talloc_free;
 345         }
 346
 347         talloc_free(smb);
 348
 349         return NT_STATUS_OK;
 350 }
 351
 352 /*
 353   return SMB server name
 354 */
 355 static const char *smb_peer_name(struct dcerpc_connection *c)
 356 {
 357         struct smb_private *smb = c->transport.private;
 358         return smb->server_name;
 359 }
 360
 361 /*
 362   fetch the user session key
 363 */
 364 static NTSTATUS smb_session_key(struct dcerpc_connection *c, DATA_BLOB *session_key)
 365 {
 366         struct smb_private *smb = c->transport.private;
 367
 368         if (smb->tree->session->user_session_key.data) {
 369                 *session_key = smb->tree->session->user_session_key;
 370                 return NT_STATUS_OK;
 371         }
 372         return NT_STATUS_NO_USER_SESSION_KEY;
 373 }
 374
 375 struct pipe_open_smb_state {
 376         union smb_open *open;
 377         struct dcerpc_connection *c;
 378         struct smbcli_request *req;
 379         struct smbcli_tree *tree;
 380         struct composite_context *ctx;
 381 };
 382
 383 static void pipe_open_recv(struct smbcli_request *req);
 384
 385 struct composite_context *dcerpc_pipe_open_smb_send(struct dcerpc_connection *c,
 386                                                     struct smbcli_tree *tree,
 387                                                     const char *pipe_name)
 388 {
 389         struct composite_context *ctx;
 390         struct pipe_open_smb_state *state;
 391
 392         ctx = talloc_zero(NULL, struct composite_context);
 393         if (ctx == NULL) goto failed;
 394         ctx->state = COMPOSITE_STATE_IN_PROGRESS;
 395         ctx->event_ctx = talloc_reference(c, c->event_ctx);
 396
 397         state = talloc(ctx, struct pipe_open_smb_state);
 398         if (state == NULL) goto failed;
 399
 400         state->c = c;
 401         state->tree = tree;
 402         state->ctx = ctx;
 403
 404         state->open = talloc(state, union smb_open);
 405         if (state->open == NULL) goto failed;
 406
 407         state->open->ntcreatex.level = RAW_OPEN_NTCREATEX;
 408         state->open->ntcreatex.in.flags = 0;
 409         state->open->ntcreatex.in.root_fid = 0;
 410         state->open->ntcreatex.in.access_mask =
 411                 SEC_STD_READ_CONTROL |
 412                 SEC_FILE_WRITE_ATTRIBUTE |
 413                 SEC_FILE_WRITE_EA |
 414                 SEC_FILE_READ_DATA |
 415                 SEC_FILE_WRITE_DATA;
 416         state->open->ntcreatex.in.file_attr = 0;
 417         state->open->ntcreatex.in.alloc_size = 0;
 418         state->open->ntcreatex.in.share_access =
 419                 NTCREATEX_SHARE_ACCESS_READ |
 420                 NTCREATEX_SHARE_ACCESS_WRITE;
 421         state->open->ntcreatex.in.open_disposition = NTCREATEX_DISP_OPEN;
 422         state->open->ntcreatex.in.create_options = 0;
 423         state->open->ntcreatex.in.impersonation =
 424                 NTCREATEX_IMPERSONATION_IMPERSONATION;
 425         state->open->ntcreatex.in.security_flags = 0;
 426
 427         if ((strncasecmp(pipe_name, "/pipe/", 6) == 0) ||
 428             (strncasecmp(pipe_name, "\\pipe\\", 6) == 0)) {
 429                 pipe_name += 6;
 430         }
 431         state->open->ntcreatex.in.fname =
 432                 (pipe_name[0] == '\\') ?
 433                 talloc_strdup(state->open, pipe_name) :
 434                 talloc_asprintf(state->open, "\\%s", pipe_name);
 435         if (state->open->ntcreatex.in.fname == NULL) goto failed;
 436
 437         state->req = smb_raw_open_send(tree, state->open);
 438         if (state->req == NULL) goto failed;
 439
 440         state->req->async.fn = pipe_open_recv;
 441         state->req->async.private = state;
 442
 443         return ctx;
 444
 445  failed:
 446         talloc_free(ctx);
 447         return NULL;
 448 }
 449
 450 static void pipe_open_recv(struct smbcli_request *req)
 451 {
 452         struct pipe_open_smb_state *state =
 453                 talloc_get_type(req->async.private,
 454                                 struct pipe_open_smb_state);
 455         struct composite_context *ctx = state->ctx;
 456         struct dcerpc_connection *c = state->c;
 457         struct smb_private *smb;
 458
 459         ctx->status = smb_raw_open_recv(req, state, state->open);
 460         if (!NT_STATUS_IS_OK(ctx->status)) goto done;
 461
 462         /*
 463           fill in the transport methods
 464         */
 465         c->transport.transport = NCACN_NP;
 466         c->transport.private = NULL;
 467         c->transport.shutdown_pipe = smb_shutdown_pipe;
 468         c->transport.peer_name = smb_peer_name;
 469
 470         c->transport.send_request = smb_send_request;
 471         c->transport.send_read = send_read_request;
 472         c->transport.recv_data = NULL;
 473
 474         /* Over-ride the default session key with the SMB session key */
 475         c->security_state.session_key = smb_session_key;
 476
 477         smb = talloc(c, struct smb_private);
 478         if (smb == NULL) {
 479                 ctx->status = NT_STATUS_NO_MEMORY;
 480                 goto done;
 481         }
 482
 483         smb->fnum       = state->open->ntcreatex.out.file.fnum;
 484         smb->tree       = talloc_reference(smb, state->tree);
 485         smb->server_name= strupper_talloc(
 486                 smb, state->tree->session->transport->called.name);
 487         if (smb->server_name == NULL) {
 488                 ctx->status = NT_STATUS_NO_MEMORY;
 489                 goto done;
 490         }
 491         c->transport.private = smb;
 492
 493         ctx->status = NT_STATUS_OK;
 494         ctx->state = COMPOSITE_STATE_DONE;
 495
 496  done:
 497         if (!NT_STATUS_IS_OK(ctx->status)) {
 498                 ctx->state = COMPOSITE_STATE_ERROR;
 499         }
 500         if ((ctx->state >= COMPOSITE_STATE_DONE) &&
 501             (ctx->async.fn != NULL)) {
 502                 ctx->async.fn(ctx);
 503         }
 504 }
 505
 506 NTSTATUS dcerpc_pipe_open_smb_recv(struct composite_context *c)
 507 {
 508         NTSTATUS status = composite_wait(c);
 509         talloc_free(c);
 510         return status;
 511 }
 512
 513 NTSTATUS dcerpc_pipe_open_smb(struct dcerpc_connection *c,
 514                               struct smbcli_tree *tree,
 515                               const char *pipe_name)
 516 {
 517         struct composite_context *ctx = dcerpc_pipe_open_smb_send(c, tree,
 518                                                                   pipe_name);
 519         return dcerpc_pipe_open_smb_recv(ctx);
 520 }
 521
 522 /*
 523   return the SMB tree used for a dcerpc over SMB pipe
 524 */
 525 struct smbcli_tree *dcerpc_smb_tree(struct dcerpc_connection *c)
 526 {
 527         struct smb_private *smb = c->transport.private;
 528
 529         if (c->transport.transport != NCACN_NP) {
 530                 return NULL;
 531         }
 532
 533         return smb->tree;
 534 }