source3/smbd/smb2_notify.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Core SMB2 server
   4
   5    Copyright (C) Stefan Metzmacher 2009
   6    Copyright (C) Jeremy Allison 2010
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "smbd/smbd.h"
  24 #include "smbd/globals.h"
  25 #include "../libcli/smb/smb_common.h"
  26 #include "../lib/util/tevent_ntstatus.h"
  27
  28 struct smbd_smb2_notify_state {
  29         struct smbd_smb2_request *smb2req;
  30         struct smb_request *smbreq;
  31         struct tevent_immediate *im;
  32         NTSTATUS status;
  33         DATA_BLOB out_output_buffer;
  34 };
  35
  36 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
  37                                                 struct tevent_context *ev,
  38                                                 struct smbd_smb2_request *smb2req,
  39                                                 uint16_t in_flags,
  40                                                 uint32_t in_output_buffer_length,
  41                                                 uint64_t in_file_id_volatile,
  42                                                 uint64_t in_completion_filter);
  43 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
  44                                       TALLOC_CTX *mem_ctx,
  45                                       DATA_BLOB *out_output_buffer);
  46
  47 static void smbd_smb2_request_notify_done(struct tevent_req *subreq);
  48 NTSTATUS smbd_smb2_request_process_notify(struct smbd_smb2_request *req)
  49 {
  50         NTSTATUS status;
  51         const uint8_t *inbody;
  52         int i = req->current_idx;
  53         uint16_t in_flags;
  54         uint32_t in_output_buffer_length;
  55         uint64_t in_file_id_persistent;
  56         uint64_t in_file_id_volatile;
  57         uint64_t in_completion_filter;
  58         struct tevent_req *subreq;
  59
  60         status = smbd_smb2_request_verify_sizes(req, 0x20);
  61         if (!NT_STATUS_IS_OK(status)) {
  62                 return smbd_smb2_request_error(req, status);
  63         }
  64         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  65
  66         in_flags                = SVAL(inbody, 0x02);
  67         in_output_buffer_length = IVAL(inbody, 0x04);
  68         in_file_id_persistent   = BVAL(inbody, 0x08);
  69         in_file_id_volatile     = BVAL(inbody, 0x10);
  70         in_completion_filter    = IVAL(inbody, 0x18);
  71
  72         /*
  73          * 0x00010000 is what Windows 7 uses,
  74          * Windows 2008 uses 0x00080000
  75          */
  76         if (in_output_buffer_length > req->sconn->smb2.max_trans) {
  77                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  78         }
  79
  80         if (req->compat_chain_fsp) {
  81                 /* skip check */
  82         } else if (in_file_id_persistent != in_file_id_volatile) {
  83                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  84         }
  85
  86         subreq = smbd_smb2_notify_send(req,
  87                                        req->sconn->ev_ctx,
  88                                        req,
  89                                        in_flags,
  90                                        in_output_buffer_length,
  91                                        in_file_id_volatile,
  92                                        in_completion_filter);
  93         if (subreq == NULL) {
  94                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
  95         }
  96         tevent_req_set_callback(subreq, smbd_smb2_request_notify_done, req);
  97
  98         return smbd_smb2_request_pending_queue(req, subreq, 500);
  99 }
 100
 101 static void smbd_smb2_request_notify_done(struct tevent_req *subreq)
 102 {
 103         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 104                                         struct smbd_smb2_request);
 105         int i = req->current_idx;
 106         uint8_t *outhdr;
 107         DATA_BLOB outbody;
 108         DATA_BLOB outdyn;
 109         uint16_t out_output_buffer_offset;
 110         DATA_BLOB out_output_buffer = data_blob_null;
 111         NTSTATUS status;
 112         NTSTATUS error; /* transport error */
 113
 114         if (req->cancelled) {
 115                 struct smbd_smb2_notify_state *state = tevent_req_data(subreq,
 116                                                struct smbd_smb2_notify_state);
 117                 const uint8_t *inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 118                 uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
 119
 120                 DEBUG(10,("smbd_smb2_request_notify_done: cancelled mid %llu\n",
 121                         (unsigned long long)mid ));
 122                 error = smbd_smb2_request_error(req, NT_STATUS_CANCELLED);
 123                 if (!NT_STATUS_IS_OK(error)) {
 124                         smbd_server_connection_terminate(req->sconn,
 125                                 nt_errstr(error));
 126                         return;
 127                 }
 128                 TALLOC_FREE(state->im);
 129                 return;
 130         }
 131
 132         status = smbd_smb2_notify_recv(subreq,
 133                                        req,
 134                                        &out_output_buffer);
 135         TALLOC_FREE(subreq);
 136         if (!NT_STATUS_IS_OK(status)) {
 137                 error = smbd_smb2_request_error(req, status);
 138                 if (!NT_STATUS_IS_OK(error)) {
 139                         smbd_server_connection_terminate(req->sconn,
 140                                                          nt_errstr(error));
 141                         return;
 142                 }
 143                 return;
 144         }
 145
 146         out_output_buffer_offset = SMB2_HDR_BODY + 0x08;
 147
 148         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 149
 150         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 151         if (outbody.data == NULL) {
 152                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 153                 if (!NT_STATUS_IS_OK(error)) {
 154                         smbd_server_connection_terminate(req->sconn,
 155                                                          nt_errstr(error));
 156                         return;
 157                 }
 158                 return;
 159         }
 160
 161         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 162         SSVAL(outbody.data, 0x02,
 163               out_output_buffer_offset);        /* output buffer offset */
 164         SIVAL(outbody.data, 0x04,
 165               out_output_buffer.length);        /* output buffer length */
 166
 167         outdyn = out_output_buffer;
 168
 169         error = smbd_smb2_request_done(req, outbody, &outdyn);
 170         if (!NT_STATUS_IS_OK(error)) {
 171                 smbd_server_connection_terminate(req->sconn,
 172                                                  nt_errstr(error));
 173                 return;
 174         }
 175 }
 176
 177 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 178                                    NTSTATUS error_code,
 179                                    uint8_t *buf, size_t len);
 180 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 181                                            struct tevent_immediate *im,
 182                                            void *private_data);
 183 static bool smbd_smb2_notify_cancel(struct tevent_req *req);
 184
 185 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
 186                                                 struct tevent_context *ev,
 187                                                 struct smbd_smb2_request *smb2req,
 188                                                 uint16_t in_flags,
 189                                                 uint32_t in_output_buffer_length,
 190                                                 uint64_t in_file_id_volatile,
 191                                                 uint64_t in_completion_filter)
 192 {
 193         struct tevent_req *req;
 194         struct smbd_smb2_notify_state *state;
 195         struct smb_request *smbreq;
 196         connection_struct *conn = smb2req->tcon->compat_conn;
 197         files_struct *fsp;
 198         bool recursive = (in_flags & 0x0001) ? true : false;
 199         NTSTATUS status;
 200
 201         req = tevent_req_create(mem_ctx, &state,
 202                                 struct smbd_smb2_notify_state);
 203         if (req == NULL) {
 204                 return NULL;
 205         }
 206         state->smb2req = smb2req;
 207         state->status = NT_STATUS_INTERNAL_ERROR;
 208         state->out_output_buffer = data_blob_null;
 209         state->im = NULL;
 210
 211         DEBUG(10,("smbd_smb2_notify_send: file_id[0x%016llX]\n",
 212                   (unsigned long long)in_file_id_volatile));
 213
 214         smbreq = smbd_smb2_fake_smb_request(smb2req);
 215         if (tevent_req_nomem(smbreq, req)) {
 216                 return tevent_req_post(req, ev);
 217         }
 218
 219         state->smbreq = smbreq;
 220         smbreq->async_priv = (void *)req;
 221
 222         fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
 223         if (fsp == NULL) {
 224                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 225                 return tevent_req_post(req, ev);
 226         }
 227         if (conn != fsp->conn) {
 228                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 229                 return tevent_req_post(req, ev);
 230         }
 231         if (smb2req->session->vuid != fsp->vuid) {
 232                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 233                 return tevent_req_post(req, ev);
 234         }
 235
 236         {
 237                 char *filter_string;
 238
 239                 filter_string = notify_filter_string(NULL, in_completion_filter);
 240                 if (tevent_req_nomem(filter_string, req)) {
 241                         return tevent_req_post(req, ev);
 242                 }
 243
 244                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 245                          "called on %s, filter = %s, recursive = %d\n",
 246                          fsp_str_dbg(fsp), filter_string, recursive));
 247
 248                 TALLOC_FREE(filter_string);
 249         }
 250
 251         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 252                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 253                 return tevent_req_post(req, ev);
 254         }
 255
 256         if (fsp->notify == NULL) {
 257
 258                 status = change_notify_create(fsp,
 259                                               in_completion_filter,
 260                                               recursive);
 261                 if (!NT_STATUS_IS_OK(status)) {
 262                         DEBUG(10, ("change_notify_create returned %s\n",
 263                                    nt_errstr(status)));
 264                         tevent_req_nterror(req, status);
 265                         return tevent_req_post(req, ev);
 266                 }
 267         }
 268
 269         if (fsp->notify->num_changes != 0) {
 270
 271                 /*
 272                  * We've got changes pending, respond immediately
 273                  */
 274
 275                 /*
 276                  * TODO: write a torture test to check the filtering behaviour
 277                  * here.
 278                  */
 279
 280                 change_notify_reply(smbreq,
 281                                     NT_STATUS_OK,
 282                                     in_output_buffer_length,
 283                                     fsp->notify,
 284                                     smbd_smb2_notify_reply);
 285
 286                 /*
 287                  * change_notify_reply() above has independently
 288                  * called tevent_req_done().
 289                  */
 290                 return tevent_req_post(req, ev);
 291         }
 292
 293         state->im = tevent_create_immediate(state);
 294         if (tevent_req_nomem(state->im, req)) {
 295                 return tevent_req_post(req, ev);
 296         }
 297
 298         /*
 299          * No changes pending, queue the request
 300          */
 301
 302         status = change_notify_add_request(smbreq,
 303                         in_output_buffer_length,
 304                         in_completion_filter,
 305                         recursive, fsp,
 306                         smbd_smb2_notify_reply);
 307         if (!NT_STATUS_IS_OK(status)) {
 308                 tevent_req_nterror(req, status);
 309                 return tevent_req_post(req, ev);
 310         }
 311
 312         /* allow this request to be canceled */
 313         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 314
 315         return req;
 316 }
 317
 318 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 319                                    NTSTATUS error_code,
 320                                    uint8_t *buf, size_t len)
 321 {
 322         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 323                                                        struct tevent_req);
 324         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 325                                                struct smbd_smb2_notify_state);
 326
 327         state->status = error_code;
 328         if (!NT_STATUS_IS_OK(error_code)) {
 329                 /* nothing */
 330         } else if (len == 0) {
 331                 state->status = STATUS_NOTIFY_ENUM_DIR;
 332         } else {
 333                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 334                 if (state->out_output_buffer.data == NULL) {
 335                         state->status = NT_STATUS_NO_MEMORY;
 336                 }
 337         }
 338
 339         if (state->im == NULL) {
 340                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 341                 return;
 342         }
 343
 344         /*
 345          * if this is called async, we need to go via an immediate event
 346          * because the caller replies on the smb_request (a child of req
 347          * being arround after calling this function
 348          */
 349         tevent_schedule_immediate(state->im,
 350                                   state->smb2req->sconn->ev_ctx,
 351                                   smbd_smb2_notify_reply_trigger,
 352                                   req);
 353 }
 354
 355 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 356                                            struct tevent_immediate *im,
 357                                            void *private_data)
 358 {
 359         struct tevent_req *req = talloc_get_type_abort(private_data,
 360                                                        struct tevent_req);
 361         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 362                                                struct smbd_smb2_notify_state);
 363
 364         if (!NT_STATUS_IS_OK(state->status)) {
 365                 tevent_req_nterror(req, state->status);
 366                 return;
 367         }
 368
 369         tevent_req_done(req);
 370 }
 371
 372 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 373 {
 374         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 375                                                struct smbd_smb2_notify_state);
 376
 377         smbd_notify_cancel_by_smbreq(state->smbreq);
 378
 379         state->smb2req->cancelled = true;
 380         tevent_req_done(req);
 381         return true;
 382 }
 383
 384 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 385                                       TALLOC_CTX *mem_ctx,
 386                                       DATA_BLOB *out_output_buffer)
 387 {
 388         NTSTATUS status;
 389         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 390                                                struct smbd_smb2_notify_state);
 391
 392         if (tevent_req_is_nterror(req, &status)) {
 393                 tevent_req_received(req);
 394                 return status;
 395         }
 396
 397         *out_output_buffer = state->out_output_buffer;
 398         talloc_steal(mem_ctx, out_output_buffer->data);
 399
 400         tevent_req_received(req);
 401         return NT_STATUS_OK;
 402 }