source4/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 "librpc/gen_ndr/ndr_security.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 };
  33
  34
  35 /*
  36   tell the dcerpc layer that the transport is dead
  37 */
  38 static void pipe_dead(struct dcerpc_connection *c, NTSTATUS status)
  39 {
  40         c->transport.recv_data(c, NULL, status);
  41 }
  42
  43
  44 /*
  45    this holds the state of an in-flight call
  46 */
  47 struct smb_read_state {
  48         struct dcerpc_connection *c;
  49         struct smbcli_request *req;
  50         size_t received;
  51         DATA_BLOB data;
  52         union smb_read *io;
  53 };
  54
  55 /*
  56   called when a read request has completed
  57 */
  58 static void smb_read_callback(struct smbcli_request *req)
  59 {
  60         struct smb_private *smb;
  61         struct smb_read_state *state;
  62         union smb_read *io;
  63         uint16_t frag_length;
  64         NTSTATUS status;
  65
  66         state = req->async.private;
  67         smb = state->c->transport.private;
  68         io = state->io;
  69
  70         status = smb_raw_read_recv(state->req, io);
  71         if (NT_STATUS_IS_ERR(status)) {
  72                 pipe_dead(state->c, status);
  73                 talloc_free(state);
  74                 return;
  75         }
  76
  77         state->received += io->readx.out.nread;
  78
  79         if (state->received < 16) {
  80                 DEBUG(0,("dcerpc_smb: short packet (length %d) in read callback!\n",
  81                          state->received));
  82                 pipe_dead(state->c, NT_STATUS_INFO_LENGTH_MISMATCH);
  83                 talloc_free(state);
  84                 return;
  85         }
  86
  87         frag_length = dcerpc_get_frag_length(&state->data);
  88
  89         if (frag_length <= state->received) {
  90                 state->data.length = state->received;
  91                 state->c->transport.recv_data(state->c, &state->data, NT_STATUS_OK);
  92                 talloc_free(state);
  93                 return;
  94         }
  95
  96         /* initiate another read request, as we only got part of a fragment */
  97         state->data.data = talloc_realloc(state, state->data.data, uint8_t, frag_length);
  98
  99         io->readx.in.mincnt = MIN(state->c->srv_max_xmit_frag,
 100                                   frag_length - state->received);
 101         io->readx.in.maxcnt = io->readx.in.mincnt;
 102         io->readx.out.data = state->data.data + state->received;
 103
 104         state->req = smb_raw_read_send(smb->tree, io);
 105         if (state->req == NULL) {
 106                 pipe_dead(state->c, NT_STATUS_NO_MEMORY);
 107                 talloc_free(state);
 108                 return;
 109         }
 110
 111         state->req->async.fn = smb_read_callback;
 112         state->req->async.private = state;
 113 }
 114
 115 /*
 116   trigger a read request from the server, possibly with some initial
 117   data in the read buffer
 118 */
 119 static NTSTATUS send_read_request_continue(struct dcerpc_connection *c, DATA_BLOB *blob)
 120 {
 121         struct smb_private *smb = c->transport.private;
 122         union smb_read *io;
 123         struct smb_read_state *state;
 124         struct smbcli_request *req;
 125
 126         state = talloc(smb, struct smb_read_state);
 127         if (state == NULL) {
 128                 return NT_STATUS_NO_MEMORY;
 129         }
 130
 131         state->c = c;
 132         if (blob == NULL) {
 133                 state->received = 0;
 134                 state->data = data_blob_talloc(state, NULL, 0x2000);
 135         } else {
 136                 uint32_t frag_length = blob->length>=16?
 137                         dcerpc_get_frag_length(blob):0x2000;
 138                 state->received = blob->length;
 139                 state->data = data_blob_talloc(state, NULL, frag_length);
 140                 if (!state->data.data) {
 141                         talloc_free(state);
 142                         return NT_STATUS_NO_MEMORY;
 143                 }
 144                 memcpy(state->data.data, blob->data, blob->length);
 145         }
 146
 147         state->io = talloc(state, union smb_read);
 148
 149         io = state->io;
 150         io->generic.level = RAW_READ_READX;
 151         io->readx.in.fnum = smb->fnum;
 152         io->readx.in.mincnt = state->data.length - state->received;
 153         io->readx.in.maxcnt = io->readx.in.mincnt;
 154         io->readx.in.offset = 0;
 155         io->readx.in.remaining = 0;
 156         io->readx.out.data = state->data.data + state->received;
 157         req = smb_raw_read_send(smb->tree, io);
 158         if (req == NULL) {
 159                 return NT_STATUS_NO_MEMORY;
 160         }
 161
 162         req->async.fn = smb_read_callback;
 163         req->async.private = state;
 164
 165         state->req = req;
 166
 167         return NT_STATUS_OK;
 168 }
 169
 170
 171 /*
 172   trigger a read request from the server
 173 */
 174 static NTSTATUS send_read_request(struct dcerpc_connection *c)
 175 {
 176         return send_read_request_continue(c, NULL);
 177 }
 178
 179 /*
 180    this holds the state of an in-flight trans call
 181 */
 182 struct smb_trans_state {
 183         struct dcerpc_connection *c;
 184         struct smbcli_request *req;
 185         struct smb_trans2 *trans;
 186 };
 187
 188 /*
 189   called when a trans request has completed
 190 */
 191 static void smb_trans_callback(struct smbcli_request *req)
 192 {
 193         struct smb_trans_state *state = req->async.private;
 194         struct dcerpc_connection *c = state->c;
 195         NTSTATUS status;
 196
 197         status = smb_raw_trans_recv(req, state, state->trans);
 198
 199         if (NT_STATUS_IS_ERR(status)) {
 200                 pipe_dead(c, status);
 201                 return;
 202         }
 203
 204         if (!NT_STATUS_EQUAL(status, STATUS_BUFFER_OVERFLOW)) {
 205                 c->transport.recv_data(c, &state->trans->out.data, NT_STATUS_OK);
 206                 talloc_free(state);
 207                 return;
 208         }
 209
 210         /* there is more to receive - setup a readx */
 211         send_read_request_continue(c, &state->trans->out.data);
 212         talloc_free(state);
 213 }
 214
 215 /*
 216   send a SMBtrans style request
 217 */
 218 static NTSTATUS smb_send_trans_request(struct dcerpc_connection *c, DATA_BLOB *blob)
 219 {
 220         struct smb_private *smb = c->transport.private;
 221         struct smb_trans2 *trans;
 222         uint16 setup[2];
 223         struct smb_trans_state *state;
 224
 225         state = talloc(smb, struct smb_trans_state);
 226         if (state == NULL) {
 227                 return NT_STATUS_NO_MEMORY;
 228         }
 229
 230         state->c = c;
 231         state->trans = talloc(state, struct smb_trans2);
 232         trans = state->trans;
 233
 234         trans->in.data = *blob;
 235         trans->in.params = data_blob(NULL, 0);
 236
 237         setup[0] = TRANSACT_DCERPCCMD;
 238         setup[1] = smb->fnum;
 239
 240         trans->in.max_param = 0;
 241         trans->in.max_data = smb_raw_max_trans_data(smb->tree, 0);
 242         trans->in.max_setup = 0;
 243         trans->in.setup_count = 2;
 244         trans->in.flags = 0;
 245         trans->in.timeout = 0;
 246         trans->in.setup = setup;
 247         trans->in.trans_name = "\\PIPE\\";
 248
 249         state->req = smb_raw_trans_send(smb->tree, trans);
 250         if (state->req == NULL) {
 251                 talloc_free(state);
 252                 return NT_STATUS_NO_MEMORY;
 253         }
 254
 255         state->req->async.fn = smb_trans_callback;
 256         state->req->async.private = state;
 257
 258         return NT_STATUS_OK;
 259 }
 260
 261 /*
 262   called when a write request has completed
 263 */
 264 static void smb_write_callback(struct smbcli_request *req)
 265 {
 266         struct dcerpc_connection *c = req->async.private;
 267
 268         if (!NT_STATUS_IS_OK(req->status)) {
 269                 DEBUG(0,("dcerpc_smb: write callback error\n"));
 270                 pipe_dead(c, req->status);
 271         }
 272
 273         smbcli_request_destroy(req);
 274 }
 275
 276 /*
 277    send a packet to the server
 278 */
 279 static NTSTATUS smb_send_request(struct dcerpc_connection *c, DATA_BLOB *blob, BOOL trigger_read)
 280 {
 281         struct smb_private *smb = c->transport.private;
 282         union smb_write io;
 283         struct smbcli_request *req;
 284
 285         if (trigger_read) {
 286                 return smb_send_trans_request(c, blob);
 287         }
 288
 289         io.generic.level = RAW_WRITE_WRITEX;
 290         io.writex.in.fnum = smb->fnum;
 291         io.writex.in.offset = 0;
 292         io.writex.in.wmode = PIPE_START_MESSAGE;
 293         io.writex.in.remaining = blob->length;
 294         io.writex.in.count = blob->length;
 295         io.writex.in.data = blob->data;
 296
 297         req = smb_raw_write_send(smb->tree, &io);
 298         if (req == NULL) {
 299                 return NT_STATUS_NO_MEMORY;
 300         }
 301
 302         req->async.fn = smb_write_callback;
 303         req->async.private = c;
 304
 305         if (trigger_read) {
 306                 send_read_request(c);
 307         }
 308
 309         return NT_STATUS_OK;
 310 }
 311
 312 /*
 313    return the event context for the pipe, so the caller can wait
 314    for events asynchronously
 315 */
 316 static struct event_context *smb_event_context(struct dcerpc_connection *c)
 317 {
 318         struct smb_private *smb = c->transport.private;
 319
 320         return smb->tree->session->transport->socket->event.ctx;
 321 }
 322
 323
 324 /*
 325    shutdown SMB pipe connection
 326 */
 327 static NTSTATUS smb_shutdown_pipe(struct dcerpc_connection *c)
 328 {
 329         struct smb_private *smb = c->transport.private;
 330         union smb_close io;
 331
 332         /* maybe we're still starting up */
 333         if (!smb) return NT_STATUS_OK;
 334
 335         io.close.level = RAW_CLOSE_CLOSE;
 336         io.close.in.fnum = smb->fnum;
 337         io.close.in.write_time = 0;
 338         smb_raw_close(smb->tree, &io);
 339
 340         talloc_free(smb);
 341
 342         return NT_STATUS_OK;
 343 }
 344
 345 /*
 346   return SMB server name
 347 */
 348 static const char *smb_peer_name(struct dcerpc_connection *c)
 349 {
 350         struct smb_private *smb = c->transport.private;
 351         return smb->tree->session->transport->called.name;
 352 }
 353
 354 /*
 355   fetch the user session key
 356 */
 357 static NTSTATUS smb_session_key(struct dcerpc_connection *c, DATA_BLOB *session_key)
 358 {
 359         struct smb_private *smb = c->transport.private;
 360
 361         if (smb->tree->session->user_session_key.data) {
 362                 *session_key = smb->tree->session->user_session_key;
 363                 return NT_STATUS_OK;
 364         }
 365         return NT_STATUS_NO_USER_SESSION_KEY;
 366 }
 367
 368 /*
 369    open a rpc connection to a named pipe
 370 */
 371 NTSTATUS dcerpc_pipe_open_smb(struct dcerpc_connection *c,
 372                               struct smbcli_tree *tree,
 373                               const char *pipe_name)
 374 {
 375         struct smb_private *smb;
 376         NTSTATUS status;
 377         union smb_open io;
 378
 379         io.ntcreatex.level = RAW_OPEN_NTCREATEX;
 380         io.ntcreatex.in.flags = 0;
 381         io.ntcreatex.in.root_fid = 0;
 382         io.ntcreatex.in.access_mask =
 383                 SEC_STD_READ_CONTROL |
 384                 SEC_FILE_WRITE_ATTRIBUTE |
 385                 SEC_FILE_WRITE_EA |
 386                 SEC_FILE_READ_DATA |
 387                 SEC_FILE_WRITE_DATA;
 388         io.ntcreatex.in.file_attr = 0;
 389         io.ntcreatex.in.alloc_size = 0;
 390         io.ntcreatex.in.share_access =
 391                 NTCREATEX_SHARE_ACCESS_READ |
 392                 NTCREATEX_SHARE_ACCESS_WRITE;
 393         io.ntcreatex.in.open_disposition = NTCREATEX_DISP_OPEN;
 394         io.ntcreatex.in.create_options = 0;
 395         io.ntcreatex.in.impersonation = NTCREATEX_IMPERSONATION_IMPERSONATION;
 396         io.ntcreatex.in.security_flags = 0;
 397         io.ntcreatex.in.fname = pipe_name;
 398
 399         status = smb_raw_open(tree, tree, &io);
 400
 401         if (!NT_STATUS_IS_OK(status)) {
 402                 return status;
 403         }
 404
 405         /*
 406           fill in the transport methods
 407         */
 408         c->transport.transport = NCACN_NP;
 409         c->transport.private = NULL;
 410         c->transport.shutdown_pipe = smb_shutdown_pipe;
 411         c->transport.peer_name = smb_peer_name;
 412
 413         c->transport.send_request = smb_send_request;
 414         c->transport.send_read = send_read_request;
 415         c->transport.event_context = smb_event_context;
 416         c->transport.recv_data = NULL;
 417
 418         /* Over-ride the default session key with the SMB session key */
 419         c->security_state.session_key = smb_session_key;
 420
 421         smb = talloc(c, struct smb_private);
 422         if (smb == NULL) {
 423                 return NT_STATUS_NO_MEMORY;
 424         }
 425
 426         smb->fnum = io.ntcreatex.out.fnum;
 427         smb->tree = tree;
 428
 429         c->transport.private = smb;
 430
 431         return NT_STATUS_OK;
 432 }
 433
 434 /*
 435   return the SMB tree used for a dcerpc over SMB pipe
 436 */
 437 struct smbcli_tree *dcerpc_smb_tree(struct dcerpc_connection *c)
 438 {
 439         struct smb_private *smb = c->transport.private;
 440
 441         if (c->transport.transport != NCACN_NP) {
 442                 return NULL;
 443         }
 444
 445         return smb->tree;
 446 }