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         const uint8_t *inhdr;
  51         const uint8_t *inbody;
  52         int i = req->current_idx;
  53         size_t expected_body_size = 0x20;
  54         size_t body_size;
  55         uint16_t in_flags;
  56         uint32_t in_output_buffer_length;
  57         uint64_t in_file_id_persistent;
  58         uint64_t in_file_id_volatile;
  59         uint64_t in_completion_filter;
  60         struct tevent_req *subreq;
  61
  62         inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
  63         if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
  64                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  65         }
  66
  67         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  68
  69         body_size = SVAL(inbody, 0x00);
  70         if (body_size != expected_body_size) {
  71                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  72         }
  73
  74         in_flags                = SVAL(inbody, 0x02);
  75         in_output_buffer_length = IVAL(inbody, 0x04);
  76         in_file_id_persistent   = BVAL(inbody, 0x08);
  77         in_file_id_volatile     = BVAL(inbody, 0x10);
  78         in_completion_filter    = IVAL(inbody, 0x18);
  79
  80         /*
  81          * 0x00010000 is what Windows 7 uses,
  82          * Windows 2008 uses 0x00080000
  83          */
  84         if (in_output_buffer_length > lp_smb2_max_trans()) {
  85                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  86         }
  87
  88         if (req->compat_chain_fsp) {
  89                 /* skip check */
  90         } else if (in_file_id_persistent != in_file_id_volatile) {
  91                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  92         }
  93
  94         subreq = smbd_smb2_notify_send(req,
  95                                        req->sconn->smb2.event_ctx,
  96                                        req,
  97                                        in_flags,
  98                                        in_output_buffer_length,
  99                                        in_file_id_volatile,
 100                                        in_completion_filter);
 101         if (subreq == NULL) {
 102                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 103         }
 104         tevent_req_set_callback(subreq, smbd_smb2_request_notify_done, req);
 105
 106         return smbd_smb2_request_pending_queue(req, subreq);
 107 }
 108
 109 static void smbd_smb2_request_notify_done(struct tevent_req *subreq)
 110 {
 111         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 112                                         struct smbd_smb2_request);
 113         int i = req->current_idx;
 114         uint8_t *outhdr;
 115         DATA_BLOB outbody;
 116         DATA_BLOB outdyn;
 117         uint16_t out_output_buffer_offset;
 118         DATA_BLOB out_output_buffer = data_blob_null;
 119         NTSTATUS status;
 120         NTSTATUS error; /* transport error */
 121
 122         if (req->cancelled) {
 123                 struct smbd_smb2_notify_state *state = tevent_req_data(subreq,
 124                                                struct smbd_smb2_notify_state);
 125                 const uint8_t *inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 126                 uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
 127
 128                 DEBUG(10,("smbd_smb2_request_notify_done: cancelled mid %llu\n",
 129                         (unsigned long long)mid ));
 130                 error = smbd_smb2_request_error(req, NT_STATUS_CANCELLED);
 131                 if (!NT_STATUS_IS_OK(error)) {
 132                         smbd_server_connection_terminate(req->sconn,
 133                                 nt_errstr(error));
 134                         return;
 135                 }
 136                 TALLOC_FREE(state->im);
 137                 return;
 138         }
 139
 140         status = smbd_smb2_notify_recv(subreq,
 141                                        req,
 142                                        &out_output_buffer);
 143         TALLOC_FREE(subreq);
 144         if (!NT_STATUS_IS_OK(status)) {
 145                 error = smbd_smb2_request_error(req, status);
 146                 if (!NT_STATUS_IS_OK(error)) {
 147                         smbd_server_connection_terminate(req->sconn,
 148                                                          nt_errstr(error));
 149                         return;
 150                 }
 151                 return;
 152         }
 153
 154         out_output_buffer_offset = SMB2_HDR_BODY + 0x08;
 155
 156         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 157
 158         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 159         if (outbody.data == NULL) {
 160                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 161                 if (!NT_STATUS_IS_OK(error)) {
 162                         smbd_server_connection_terminate(req->sconn,
 163                                                          nt_errstr(error));
 164                         return;
 165                 }
 166                 return;
 167         }
 168
 169         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 170         SSVAL(outbody.data, 0x02,
 171               out_output_buffer_offset);        /* output buffer offset */
 172         SIVAL(outbody.data, 0x04,
 173               out_output_buffer.length);        /* output buffer length */
 174
 175         outdyn = out_output_buffer;
 176
 177         error = smbd_smb2_request_done(req, outbody, &outdyn);
 178         if (!NT_STATUS_IS_OK(error)) {
 179                 smbd_server_connection_terminate(req->sconn,
 180                                                  nt_errstr(error));
 181                 return;
 182         }
 183 }
 184
 185 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 186                                    NTSTATUS error_code,
 187                                    uint8_t *buf, size_t len);
 188 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 189                                            struct tevent_immediate *im,
 190                                            void *private_data);
 191 static bool smbd_smb2_notify_cancel(struct tevent_req *req);
 192
 193 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
 194                                                 struct tevent_context *ev,
 195                                                 struct smbd_smb2_request *smb2req,
 196                                                 uint16_t in_flags,
 197                                                 uint32_t in_output_buffer_length,
 198                                                 uint64_t in_file_id_volatile,
 199                                                 uint64_t in_completion_filter)
 200 {
 201         struct tevent_req *req;
 202         struct smbd_smb2_notify_state *state;
 203         struct smb_request *smbreq;
 204         connection_struct *conn = smb2req->tcon->compat_conn;
 205         files_struct *fsp;
 206         bool recursive = (in_flags & 0x0001) ? true : false;
 207         NTSTATUS status;
 208
 209         req = tevent_req_create(mem_ctx, &state,
 210                                 struct smbd_smb2_notify_state);
 211         if (req == NULL) {
 212                 return NULL;
 213         }
 214         state->smb2req = smb2req;
 215         state->status = NT_STATUS_INTERNAL_ERROR;
 216         state->out_output_buffer = data_blob_null;
 217         state->im = NULL;
 218
 219         DEBUG(10,("smbd_smb2_notify_send: file_id[0x%016llX]\n",
 220                   (unsigned long long)in_file_id_volatile));
 221
 222         smbreq = smbd_smb2_fake_smb_request(smb2req);
 223         if (tevent_req_nomem(smbreq, req)) {
 224                 return tevent_req_post(req, ev);
 225         }
 226
 227         state->smbreq = smbreq;
 228         smbreq->async_priv = (void *)req;
 229
 230         fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
 231         if (fsp == NULL) {
 232                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 233                 return tevent_req_post(req, ev);
 234         }
 235         if (conn != fsp->conn) {
 236                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 237                 return tevent_req_post(req, ev);
 238         }
 239         if (smb2req->session->vuid != fsp->vuid) {
 240                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 241                 return tevent_req_post(req, ev);
 242         }
 243
 244         {
 245                 char *filter_string;
 246
 247                 filter_string = notify_filter_string(NULL, in_completion_filter);
 248                 if (tevent_req_nomem(filter_string, req)) {
 249                         return tevent_req_post(req, ev);
 250                 }
 251
 252                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 253                          "called on %s, filter = %s, recursive = %d\n",
 254                          fsp_str_dbg(fsp), filter_string, recursive));
 255
 256                 TALLOC_FREE(filter_string);
 257         }
 258
 259         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 260                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 261                 return tevent_req_post(req, ev);
 262         }
 263
 264         if (fsp->notify == NULL) {
 265
 266                 status = change_notify_create(fsp,
 267                                               in_completion_filter,
 268                                               recursive);
 269                 if (!NT_STATUS_IS_OK(status)) {
 270                         DEBUG(10, ("change_notify_create returned %s\n",
 271                                    nt_errstr(status)));
 272                         tevent_req_nterror(req, status);
 273                         return tevent_req_post(req, ev);
 274                 }
 275         }
 276
 277         if (fsp->notify->num_changes != 0) {
 278
 279                 /*
 280                  * We've got changes pending, respond immediately
 281                  */
 282
 283                 /*
 284                  * TODO: write a torture test to check the filtering behaviour
 285                  * here.
 286                  */
 287
 288                 change_notify_reply(smbreq,
 289                                     NT_STATUS_OK,
 290                                     in_output_buffer_length,
 291                                     fsp->notify,
 292                                     smbd_smb2_notify_reply);
 293
 294                 /*
 295                  * change_notify_reply() above has independently
 296                  * called tevent_req_done().
 297                  */
 298                 return tevent_req_post(req, ev);
 299         }
 300
 301         state->im = tevent_create_immediate(state);
 302         if (tevent_req_nomem(state->im, req)) {
 303                 return tevent_req_post(req, ev);
 304         }
 305
 306         /*
 307          * No changes pending, queue the request
 308          */
 309
 310         status = change_notify_add_request(smbreq,
 311                         in_output_buffer_length,
 312                         in_completion_filter,
 313                         recursive, fsp,
 314                         smbd_smb2_notify_reply);
 315         if (!NT_STATUS_IS_OK(status)) {
 316                 tevent_req_nterror(req, status);
 317                 return tevent_req_post(req, ev);
 318         }
 319
 320         /* allow this request to be canceled */
 321         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 322
 323         return req;
 324 }
 325
 326 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 327                                    NTSTATUS error_code,
 328                                    uint8_t *buf, size_t len)
 329 {
 330         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 331                                                        struct tevent_req);
 332         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 333                                                struct smbd_smb2_notify_state);
 334
 335         state->status = error_code;
 336         if (!NT_STATUS_IS_OK(error_code)) {
 337                 /* nothing */
 338         } else if (len == 0) {
 339                 state->status = STATUS_NOTIFY_ENUM_DIR;
 340         } else {
 341                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 342                 if (state->out_output_buffer.data == NULL) {
 343                         state->status = NT_STATUS_NO_MEMORY;
 344                 }
 345         }
 346
 347         if (state->im == NULL) {
 348                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 349                 return;
 350         }
 351
 352         /*
 353          * if this is called async, we need to go via an immediate event
 354          * because the caller replies on the smb_request (a child of req
 355          * being arround after calling this function
 356          */
 357         tevent_schedule_immediate(state->im,
 358                                   state->smb2req->sconn->smb2.event_ctx,
 359                                   smbd_smb2_notify_reply_trigger,
 360                                   req);
 361 }
 362
 363 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 364                                            struct tevent_immediate *im,
 365                                            void *private_data)
 366 {
 367         struct tevent_req *req = talloc_get_type_abort(private_data,
 368                                                        struct tevent_req);
 369         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 370                                                struct smbd_smb2_notify_state);
 371
 372         if (!NT_STATUS_IS_OK(state->status)) {
 373                 tevent_req_nterror(req, state->status);
 374                 return;
 375         }
 376
 377         tevent_req_done(req);
 378 }
 379
 380 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 381 {
 382         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 383                                                struct smbd_smb2_notify_state);
 384
 385         smbd_notify_cancel_by_smbreq(state->smbreq);
 386
 387         state->smb2req->cancelled = true;
 388         tevent_req_done(req);
 389         return true;
 390 }
 391
 392 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 393                                       TALLOC_CTX *mem_ctx,
 394                                       DATA_BLOB *out_output_buffer)
 395 {
 396         NTSTATUS status;
 397         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 398                                                struct smbd_smb2_notify_state);
 399
 400         if (tevent_req_is_nterror(req, &status)) {
 401                 tevent_req_received(req);
 402                 return status;
 403         }
 404
 405         *out_output_buffer = state->out_output_buffer;
 406         talloc_steal(mem_ctx, out_output_buffer->data);
 407
 408         tevent_req_received(req);
 409         return NT_STATUS_OK;
 410 }