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                                                 struct files_struct *in_fsp,
  40                                                 uint16_t in_flags,
  41                                                 uint32_t in_output_buffer_length,
  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         struct files_struct *in_fsp;
  58         uint64_t in_completion_filter;
  59         struct tevent_req *subreq;
  60
  61         status = smbd_smb2_request_verify_sizes(req, 0x20);
  62         if (!NT_STATUS_IS_OK(status)) {
  63                 return smbd_smb2_request_error(req, status);
  64         }
  65         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  66
  67         in_flags                = SVAL(inbody, 0x02);
  68         in_output_buffer_length = IVAL(inbody, 0x04);
  69         in_file_id_persistent   = BVAL(inbody, 0x08);
  70         in_file_id_volatile     = BVAL(inbody, 0x10);
  71         in_completion_filter    = IVAL(inbody, 0x18);
  72
  73         /*
  74          * 0x00010000 is what Windows 7 uses,
  75          * Windows 2008 uses 0x00080000
  76          */
  77         if (in_output_buffer_length > req->sconn->smb2.max_trans) {
  78                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  79         }
  80
  81         in_fsp = file_fsp_smb2(req, in_file_id_persistent, in_file_id_volatile);
  82         if (in_fsp == NULL) {
  83                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  84         }
  85
  86         subreq = smbd_smb2_notify_send(req, req->sconn->smb2.event_ctx,
  87                                        req, in_fsp,
  88                                        in_flags,
  89                                        in_output_buffer_length,
  90                                        in_completion_filter);
  91         if (subreq == NULL) {
  92                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
  93         }
  94         tevent_req_set_callback(subreq, smbd_smb2_request_notify_done, req);
  95
  96         return smbd_smb2_request_pending_queue(req, subreq);
  97 }
  98
  99 static void smbd_smb2_request_notify_done(struct tevent_req *subreq)
 100 {
 101         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 102                                         struct smbd_smb2_request);
 103         int i = req->current_idx;
 104         uint8_t *outhdr;
 105         DATA_BLOB outbody;
 106         DATA_BLOB outdyn;
 107         uint16_t out_output_buffer_offset;
 108         DATA_BLOB out_output_buffer = data_blob_null;
 109         NTSTATUS status;
 110         NTSTATUS error; /* transport error */
 111
 112         if (req->cancelled) {
 113                 struct smbd_smb2_notify_state *state = tevent_req_data(subreq,
 114                                                struct smbd_smb2_notify_state);
 115                 const uint8_t *inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 116                 uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
 117
 118                 DEBUG(10,("smbd_smb2_request_notify_done: cancelled mid %llu\n",
 119                         (unsigned long long)mid ));
 120                 error = smbd_smb2_request_error(req, NT_STATUS_CANCELLED);
 121                 if (!NT_STATUS_IS_OK(error)) {
 122                         smbd_server_connection_terminate(req->sconn,
 123                                 nt_errstr(error));
 124                         return;
 125                 }
 126                 TALLOC_FREE(state->im);
 127                 return;
 128         }
 129
 130         status = smbd_smb2_notify_recv(subreq,
 131                                        req,
 132                                        &out_output_buffer);
 133         TALLOC_FREE(subreq);
 134         if (!NT_STATUS_IS_OK(status)) {
 135                 error = smbd_smb2_request_error(req, status);
 136                 if (!NT_STATUS_IS_OK(error)) {
 137                         smbd_server_connection_terminate(req->sconn,
 138                                                          nt_errstr(error));
 139                         return;
 140                 }
 141                 return;
 142         }
 143
 144         out_output_buffer_offset = SMB2_HDR_BODY + 0x08;
 145
 146         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 147
 148         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 149         if (outbody.data == NULL) {
 150                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 151                 if (!NT_STATUS_IS_OK(error)) {
 152                         smbd_server_connection_terminate(req->sconn,
 153                                                          nt_errstr(error));
 154                         return;
 155                 }
 156                 return;
 157         }
 158
 159         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 160         SSVAL(outbody.data, 0x02,
 161               out_output_buffer_offset);        /* output buffer offset */
 162         SIVAL(outbody.data, 0x04,
 163               out_output_buffer.length);        /* output buffer length */
 164
 165         outdyn = out_output_buffer;
 166
 167         error = smbd_smb2_request_done(req, outbody, &outdyn);
 168         if (!NT_STATUS_IS_OK(error)) {
 169                 smbd_server_connection_terminate(req->sconn,
 170                                                  nt_errstr(error));
 171                 return;
 172         }
 173 }
 174
 175 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 176                                    NTSTATUS error_code,
 177                                    uint8_t *buf, size_t len);
 178 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 179                                            struct tevent_immediate *im,
 180                                            void *private_data);
 181 static bool smbd_smb2_notify_cancel(struct tevent_req *req);
 182
 183 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
 184                                                 struct tevent_context *ev,
 185                                                 struct smbd_smb2_request *smb2req,
 186                                                 struct files_struct *fsp,
 187                                                 uint16_t in_flags,
 188                                                 uint32_t in_output_buffer_length,
 189                                                 uint64_t in_completion_filter)
 190 {
 191         struct tevent_req *req;
 192         struct smbd_smb2_notify_state *state;
 193         struct smb_request *smbreq;
 194         connection_struct *conn = smb2req->tcon->compat_conn;
 195         bool recursive = (in_flags & 0x0001) ? true : false;
 196         NTSTATUS status;
 197
 198         req = tevent_req_create(mem_ctx, &state,
 199                                 struct smbd_smb2_notify_state);
 200         if (req == NULL) {
 201                 return NULL;
 202         }
 203         state->smb2req = smb2req;
 204         state->status = NT_STATUS_INTERNAL_ERROR;
 205         state->out_output_buffer = data_blob_null;
 206         state->im = NULL;
 207
 208         DEBUG(10,("smbd_smb2_notify_send: %s - fnum[%d]\n",
 209                   fsp_str_dbg(fsp), fsp->fnum));
 210
 211         smbreq = smbd_smb2_fake_smb_request(smb2req);
 212         if (tevent_req_nomem(smbreq, req)) {
 213                 return tevent_req_post(req, ev);
 214         }
 215
 216         state->smbreq = smbreq;
 217         smbreq->async_priv = (void *)req;
 218
 219         {
 220                 char *filter_string;
 221
 222                 filter_string = notify_filter_string(NULL, in_completion_filter);
 223                 if (tevent_req_nomem(filter_string, req)) {
 224                         return tevent_req_post(req, ev);
 225                 }
 226
 227                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 228                          "called on %s, filter = %s, recursive = %d\n",
 229                          fsp_str_dbg(fsp), filter_string, recursive));
 230
 231                 TALLOC_FREE(filter_string);
 232         }
 233
 234         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 235                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 236                 return tevent_req_post(req, ev);
 237         }
 238
 239         if (fsp->notify == NULL) {
 240
 241                 status = change_notify_create(fsp,
 242                                               in_completion_filter,
 243                                               recursive);
 244                 if (!NT_STATUS_IS_OK(status)) {
 245                         DEBUG(10, ("change_notify_create returned %s\n",
 246                                    nt_errstr(status)));
 247                         tevent_req_nterror(req, status);
 248                         return tevent_req_post(req, ev);
 249                 }
 250         }
 251
 252         if (fsp->notify->num_changes != 0) {
 253
 254                 /*
 255                  * We've got changes pending, respond immediately
 256                  */
 257
 258                 /*
 259                  * TODO: write a torture test to check the filtering behaviour
 260                  * here.
 261                  */
 262
 263                 change_notify_reply(smbreq,
 264                                     NT_STATUS_OK,
 265                                     in_output_buffer_length,
 266                                     fsp->notify,
 267                                     smbd_smb2_notify_reply);
 268
 269                 /*
 270                  * change_notify_reply() above has independently
 271                  * called tevent_req_done().
 272                  */
 273                 return tevent_req_post(req, ev);
 274         }
 275
 276         state->im = tevent_create_immediate(state);
 277         if (tevent_req_nomem(state->im, req)) {
 278                 return tevent_req_post(req, ev);
 279         }
 280
 281         /*
 282          * No changes pending, queue the request
 283          */
 284
 285         status = change_notify_add_request(smbreq,
 286                         in_output_buffer_length,
 287                         in_completion_filter,
 288                         recursive, fsp,
 289                         smbd_smb2_notify_reply);
 290         if (!NT_STATUS_IS_OK(status)) {
 291                 tevent_req_nterror(req, status);
 292                 return tevent_req_post(req, ev);
 293         }
 294
 295         /* allow this request to be canceled */
 296         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 297
 298         return req;
 299 }
 300
 301 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 302                                    NTSTATUS error_code,
 303                                    uint8_t *buf, size_t len)
 304 {
 305         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 306                                                        struct tevent_req);
 307         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 308                                                struct smbd_smb2_notify_state);
 309
 310         state->status = error_code;
 311         if (!NT_STATUS_IS_OK(error_code)) {
 312                 /* nothing */
 313         } else if (len == 0) {
 314                 state->status = STATUS_NOTIFY_ENUM_DIR;
 315         } else {
 316                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 317                 if (state->out_output_buffer.data == NULL) {
 318                         state->status = NT_STATUS_NO_MEMORY;
 319                 }
 320         }
 321
 322         if (state->im == NULL) {
 323                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 324                 return;
 325         }
 326
 327         /*
 328          * if this is called async, we need to go via an immediate event
 329          * because the caller replies on the smb_request (a child of req
 330          * being arround after calling this function
 331          */
 332         tevent_schedule_immediate(state->im,
 333                                   state->smb2req->sconn->smb2.event_ctx,
 334                                   smbd_smb2_notify_reply_trigger,
 335                                   req);
 336 }
 337
 338 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 339                                            struct tevent_immediate *im,
 340                                            void *private_data)
 341 {
 342         struct tevent_req *req = talloc_get_type_abort(private_data,
 343                                                        struct tevent_req);
 344         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 345                                                struct smbd_smb2_notify_state);
 346
 347         if (!NT_STATUS_IS_OK(state->status)) {
 348                 tevent_req_nterror(req, state->status);
 349                 return;
 350         }
 351
 352         tevent_req_done(req);
 353 }
 354
 355 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 356 {
 357         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 358                                                struct smbd_smb2_notify_state);
 359
 360         state->smb2req->cancelled = true;
 361         smbd_notify_cancel_by_smbreq(state->smbreq);
 362
 363         return true;
 364 }
 365
 366 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 367                                       TALLOC_CTX *mem_ctx,
 368                                       DATA_BLOB *out_output_buffer)
 369 {
 370         NTSTATUS status;
 371         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 372                                                struct smbd_smb2_notify_state);
 373
 374         if (tevent_req_is_nterror(req, &status)) {
 375                 tevent_req_received(req);
 376                 return status;
 377         }
 378
 379         *out_output_buffer = state->out_output_buffer;
 380         talloc_steal(mem_ctx, out_output_buffer->data);
 381
 382         tevent_req_received(req);
 383         return NT_STATUS_OK;
 384 }