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