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