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