source3/smbd/smb2_notify.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Core SMB2 server
   4
   5    Copyright (C) Stefan Metzmacher 2009
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "smbd/globals.h"
  23 #include "../libcli/smb/smb_common.h"
  24
  25 struct smbd_smb2_notify_state {
  26         struct smbd_smb2_request *smb2req;
  27         struct smb_request *smbreq;
  28         struct tevent_immediate *im;
  29         NTSTATUS status;
  30         DATA_BLOB out_output_buffer;
  31 };
  32
  33 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
  34                                                 struct tevent_context *ev,
  35                                                 struct smbd_smb2_request *smb2req,
  36                                                 uint16_t in_flags,
  37                                                 uint32_t in_output_buffer_length,
  38                                                 uint64_t in_file_id_volatile,
  39                                                 uint64_t in_completion_filter);
  40 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
  41                                       TALLOC_CTX *mem_ctx,
  42                                       DATA_BLOB *out_output_buffer);
  43
  44 static void smbd_smb2_request_notify_done(struct tevent_req *subreq);
  45 NTSTATUS smbd_smb2_request_process_notify(struct smbd_smb2_request *req)
  46 {
  47         const uint8_t *inhdr;
  48         const uint8_t *inbody;
  49         int i = req->current_idx;
  50         size_t expected_body_size = 0x20;
  51         size_t body_size;
  52         uint16_t in_flags;
  53         uint32_t in_output_buffer_length;
  54         uint64_t in_file_id_persistent;
  55         uint64_t in_file_id_volatile;
  56         uint64_t in_completion_filter;
  57         struct tevent_req *subreq;
  58
  59         inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
  60         if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
  61                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  62         }
  63
  64         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  65
  66         body_size = SVAL(inbody, 0x00);
  67         if (body_size != expected_body_size) {
  68                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  69         }
  70
  71         in_flags                = SVAL(inbody, 0x02);
  72         in_output_buffer_length = IVAL(inbody, 0x04);
  73         in_file_id_persistent   = BVAL(inbody, 0x08);
  74         in_file_id_volatile     = BVAL(inbody, 0x10);
  75         in_completion_filter    = IVAL(inbody, 0x18);
  76
  77         /*
  78          * 0x00010000 is what Windows 7 uses,
  79          * Windows 2008 uses 0x00080000
  80          */
  81         if (in_output_buffer_length > lp_smb2_max_trans()) {
  82                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  83         }
  84
  85         if (req->compat_chain_fsp) {
  86                 /* skip check */
  87         } else if (in_file_id_persistent != 0) {
  88                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  89         }
  90
  91         subreq = smbd_smb2_notify_send(req,
  92                                        req->sconn->smb2.event_ctx,
  93                                        req,
  94                                        in_flags,
  95                                        in_output_buffer_length,
  96                                        in_file_id_volatile,
  97                                        in_completion_filter);
  98         if (subreq == NULL) {
  99                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 100         }
 101         tevent_req_set_callback(subreq, smbd_smb2_request_notify_done, req);
 102
 103         return smbd_smb2_request_pending_queue(req, subreq);
 104 }
 105
 106 static void smbd_smb2_request_notify_done(struct tevent_req *subreq)
 107 {
 108         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 109                                         struct smbd_smb2_request);
 110         int i = req->current_idx;
 111         uint8_t *outhdr;
 112         DATA_BLOB outbody;
 113         DATA_BLOB outdyn;
 114         uint16_t out_output_buffer_offset;
 115         DATA_BLOB out_output_buffer = data_blob_null;
 116         NTSTATUS status;
 117         NTSTATUS error; /* transport error */
 118
 119         if (req->cancelled) {
 120                 struct smbd_smb2_notify_state *state = tevent_req_data(subreq,
 121                                                struct smbd_smb2_notify_state);
 122                 const uint8_t *inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 123                 uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
 124
 125                 DEBUG(10,("smbd_smb2_request_notify_done: cancelled mid %llu\n",
 126                         (unsigned long long)mid ));
 127                 error = smbd_smb2_request_error(req, NT_STATUS_CANCELLED);
 128                 if (!NT_STATUS_IS_OK(error)) {
 129                         smbd_server_connection_terminate(req->sconn,
 130                                 nt_errstr(error));
 131                         return;
 132                 }
 133                 TALLOC_FREE(state->im);
 134                 return;
 135         }
 136
 137         status = smbd_smb2_notify_recv(subreq,
 138                                        req,
 139                                        &out_output_buffer);
 140         TALLOC_FREE(subreq);
 141         if (!NT_STATUS_IS_OK(status)) {
 142                 error = smbd_smb2_request_error(req, status);
 143                 if (!NT_STATUS_IS_OK(error)) {
 144                         smbd_server_connection_terminate(req->sconn,
 145                                                          nt_errstr(error));
 146                         return;
 147                 }
 148                 return;
 149         }
 150
 151         out_output_buffer_offset = SMB2_HDR_BODY + 0x08;
 152
 153         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 154
 155         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 156         if (outbody.data == NULL) {
 157                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 158                 if (!NT_STATUS_IS_OK(error)) {
 159                         smbd_server_connection_terminate(req->sconn,
 160                                                          nt_errstr(error));
 161                         return;
 162                 }
 163                 return;
 164         }
 165
 166         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 167         SSVAL(outbody.data, 0x02,
 168               out_output_buffer_offset);        /* output buffer offset */
 169         SIVAL(outbody.data, 0x04,
 170               out_output_buffer.length);        /* output buffer length */
 171
 172         outdyn = out_output_buffer;
 173
 174         error = smbd_smb2_request_done(req, outbody, &outdyn);
 175         if (!NT_STATUS_IS_OK(error)) {
 176                 smbd_server_connection_terminate(req->sconn,
 177                                                  nt_errstr(error));
 178                 return;
 179         }
 180 }
 181
 182 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 183                                    NTSTATUS error_code,
 184                                    uint8_t *buf, size_t len);
 185 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 186                                            struct tevent_immediate *im,
 187                                            void *private_data);
 188 static bool smbd_smb2_notify_cancel(struct tevent_req *req);
 189
 190 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
 191                                                 struct tevent_context *ev,
 192                                                 struct smbd_smb2_request *smb2req,
 193                                                 uint16_t in_flags,
 194                                                 uint32_t in_output_buffer_length,
 195                                                 uint64_t in_file_id_volatile,
 196                                                 uint64_t in_completion_filter)
 197 {
 198         struct tevent_req *req;
 199         struct smbd_smb2_notify_state *state;
 200         struct smb_request *smbreq;
 201         connection_struct *conn = smb2req->tcon->compat_conn;
 202         files_struct *fsp;
 203         bool recursive = (in_flags & 0x0001) ? true : false;
 204         NTSTATUS status;
 205
 206         req = tevent_req_create(mem_ctx, &state,
 207                                 struct smbd_smb2_notify_state);
 208         if (req == NULL) {
 209                 return NULL;
 210         }
 211         state->smb2req = smb2req;
 212         state->status = NT_STATUS_INTERNAL_ERROR;
 213         state->out_output_buffer = data_blob_null;
 214         state->im = NULL;
 215
 216         DEBUG(10,("smbd_smb2_notify_send: file_id[0x%016llX]\n",
 217                   (unsigned long long)in_file_id_volatile));
 218
 219         smbreq = smbd_smb2_fake_smb_request(smb2req);
 220         if (tevent_req_nomem(smbreq, req)) {
 221                 return tevent_req_post(req, ev);
 222         }
 223
 224         state->smbreq = smbreq;
 225         smbreq->async_priv = (void *)req;
 226
 227         fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
 228         if (fsp == NULL) {
 229                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 230                 return tevent_req_post(req, ev);
 231         }
 232         if (conn != fsp->conn) {
 233                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 234                 return tevent_req_post(req, ev);
 235         }
 236         if (smb2req->session->vuid != fsp->vuid) {
 237                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 238                 return tevent_req_post(req, ev);
 239         }
 240
 241         {
 242                 char *filter_string;
 243
 244                 filter_string = notify_filter_string(NULL, in_completion_filter);
 245                 if (tevent_req_nomem(filter_string, req)) {
 246                         return tevent_req_post(req, ev);
 247                 }
 248
 249                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 250                          "called on %s, filter = %s, recursive = %d\n",
 251                          fsp_str_dbg(fsp), filter_string, recursive));
 252
 253                 TALLOC_FREE(filter_string);
 254         }
 255
 256         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 257                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 258                 return tevent_req_post(req, ev);
 259         }
 260
 261         if (fsp->notify == NULL) {
 262
 263                 status = change_notify_create(fsp,
 264                                               in_completion_filter,
 265                                               recursive);
 266                 if (!NT_STATUS_IS_OK(status)) {
 267                         DEBUG(10, ("change_notify_create returned %s\n",
 268                                    nt_errstr(status)));
 269                         tevent_req_nterror(req, status);
 270                         return tevent_req_post(req, ev);
 271                 }
 272         }
 273
 274         if (fsp->notify->num_changes != 0) {
 275
 276                 /*
 277                  * We've got changes pending, respond immediately
 278                  */
 279
 280                 /*
 281                  * TODO: write a torture test to check the filtering behaviour
 282                  * here.
 283                  */
 284
 285                 change_notify_reply(fsp->conn, smbreq,
 286                                     NT_STATUS_OK,
 287                                     in_output_buffer_length,
 288                                     fsp->notify,
 289                                     smbd_smb2_notify_reply);
 290
 291                 /*
 292                  * change_notify_reply() above has independently
 293                  * called tevent_req_done().
 294                  */
 295                 return tevent_req_post(req, ev);
 296         }
 297
 298         state->im = tevent_create_immediate(state);
 299         if (tevent_req_nomem(state->im, req)) {
 300                 return tevent_req_post(req, ev);
 301         }
 302
 303         /*
 304          * No changes pending, queue the request
 305          */
 306
 307         status = change_notify_add_request(smbreq,
 308                         in_output_buffer_length,
 309                         in_completion_filter,
 310                         recursive, fsp,
 311                         smbd_smb2_notify_reply);
 312         if (!NT_STATUS_IS_OK(status)) {
 313                 tevent_req_nterror(req, status);
 314                 return tevent_req_post(req, ev);
 315         }
 316
 317         /* allow this request to be canceled */
 318         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 319
 320         return req;
 321 }
 322
 323 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 324                                    NTSTATUS error_code,
 325                                    uint8_t *buf, size_t len)
 326 {
 327         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 328                                                        struct tevent_req);
 329         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 330                                                struct smbd_smb2_notify_state);
 331
 332         state->status = error_code;
 333         if (!NT_STATUS_IS_OK(error_code)) {
 334                 /* nothing */
 335         } else if (len == 0) {
 336                 state->status = STATUS_NOTIFY_ENUM_DIR;
 337         } else {
 338                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 339                 if (state->out_output_buffer.data == NULL) {
 340                         state->status = NT_STATUS_NO_MEMORY;
 341                 }
 342         }
 343
 344         if (state->im == NULL) {
 345                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 346                 return;
 347         }
 348
 349         /*
 350          * if this is called async, we need to go via an immediate event
 351          * because the caller replies on the smb_request (a child of req
 352          * being arround after calling this function
 353          */
 354         tevent_schedule_immediate(state->im,
 355                                   state->smb2req->sconn->smb2.event_ctx,
 356                                   smbd_smb2_notify_reply_trigger,
 357                                   req);
 358 }
 359
 360 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 361                                            struct tevent_immediate *im,
 362                                            void *private_data)
 363 {
 364         struct tevent_req *req = talloc_get_type_abort(private_data,
 365                                                        struct tevent_req);
 366         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 367                                                struct smbd_smb2_notify_state);
 368
 369         if (!NT_STATUS_IS_OK(state->status)) {
 370                 tevent_req_nterror(req, state->status);
 371                 return;
 372         }
 373
 374         tevent_req_done(req);
 375 }
 376
 377 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 378 {
 379         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 380                                                struct smbd_smb2_notify_state);
 381
 382         smbd_notify_cancel_by_smbreq(state->smb2req->sconn,
 383                                      state->smbreq);
 384
 385         state->smb2req->cancelled = true;
 386         tevent_req_done(req);
 387         return true;
 388 }
 389
 390 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 391                                       TALLOC_CTX *mem_ctx,
 392                                       DATA_BLOB *out_output_buffer)
 393 {
 394         NTSTATUS status;
 395         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 396                                                struct smbd_smb2_notify_state);
 397
 398         if (tevent_req_is_nterror(req, &status)) {
 399                 tevent_req_received(req);
 400                 return status;
 401         }
 402
 403         *out_output_buffer = state->out_output_buffer;
 404         talloc_steal(mem_ctx, out_output_buffer->data);
 405
 406         tevent_req_received(req);
 407         return NT_STATUS_OK;
 408 }