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         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         uint64_t in_completion_filter;
  58         struct tevent_req *subreq;
  59
  60         status = smbd_smb2_request_verify_sizes(req, 0x20);
  61         if (!NT_STATUS_IS_OK(status)) {
  62                 return smbd_smb2_request_error(req, status);
  63         }
  64         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  65
  66         in_flags                = SVAL(inbody, 0x02);
  67         in_output_buffer_length = IVAL(inbody, 0x04);
  68         in_file_id_persistent   = BVAL(inbody, 0x08);
  69         in_file_id_volatile     = BVAL(inbody, 0x10);
  70         in_completion_filter    = IVAL(inbody, 0x18);
  71
  72         /*
  73          * 0x00010000 is what Windows 7 uses,
  74          * Windows 2008 uses 0x00080000
  75          */
  76         if (in_output_buffer_length > req->sconn->smb2.max_trans) {
  77                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  78         }
  79
  80         status = smbd_smb2_request_verify_creditcharge(req,
  81                                                 in_output_buffer_length);
  82
  83         if (!NT_STATUS_IS_OK(status)) {
  84                 return smbd_smb2_request_error(req, status);
  85         }
  86
  87         if (req->compat_chain_fsp) {
  88                 /* skip check */
  89         } else if (in_file_id_persistent != in_file_id_volatile) {
  90                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  91         }
  92
  93         subreq = smbd_smb2_notify_send(req,
  94                                        req->sconn->ev_ctx,
  95                                        req,
  96                                        in_flags,
  97                                        in_output_buffer_length,
  98                                        in_file_id_volatile,
  99                                        in_completion_filter);
 100         if (subreq == NULL) {
 101                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 102         }
 103         tevent_req_set_callback(subreq, smbd_smb2_request_notify_done, req);
 104
 105         return smbd_smb2_request_pending_queue(req, subreq, 500);
 106 }
 107
 108 static void smbd_smb2_request_notify_done(struct tevent_req *subreq)
 109 {
 110         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 111                                         struct smbd_smb2_request);
 112         int i = req->current_idx;
 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         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 155         if (outbody.data == NULL) {
 156                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 157                 if (!NT_STATUS_IS_OK(error)) {
 158                         smbd_server_connection_terminate(req->sconn,
 159                                                          nt_errstr(error));
 160                         return;
 161                 }
 162                 return;
 163         }
 164
 165         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 166         SSVAL(outbody.data, 0x02,
 167               out_output_buffer_offset);        /* output buffer offset */
 168         SIVAL(outbody.data, 0x04,
 169               out_output_buffer.length);        /* output buffer length */
 170
 171         outdyn = out_output_buffer;
 172
 173         error = smbd_smb2_request_done(req, outbody, &outdyn);
 174         if (!NT_STATUS_IS_OK(error)) {
 175                 smbd_server_connection_terminate(req->sconn,
 176                                                  nt_errstr(error));
 177                 return;
 178         }
 179 }
 180
 181 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 182                                    NTSTATUS error_code,
 183                                    uint8_t *buf, size_t len);
 184 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 185                                            struct tevent_immediate *im,
 186                                            void *private_data);
 187 static bool smbd_smb2_notify_cancel(struct tevent_req *req);
 188
 189 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
 190                                                 struct tevent_context *ev,
 191                                                 struct smbd_smb2_request *smb2req,
 192                                                 uint16_t in_flags,
 193                                                 uint32_t in_output_buffer_length,
 194                                                 uint64_t in_file_id_volatile,
 195                                                 uint64_t in_completion_filter)
 196 {
 197         struct tevent_req *req;
 198         struct smbd_smb2_notify_state *state;
 199         struct smb_request *smbreq;
 200         connection_struct *conn = smb2req->tcon->compat;
 201         files_struct *fsp;
 202         bool recursive = (in_flags & SMB2_WATCH_TREE) ? true : false;
 203         NTSTATUS status;
 204
 205         req = tevent_req_create(mem_ctx, &state,
 206                                 struct smbd_smb2_notify_state);
 207         if (req == NULL) {
 208                 return NULL;
 209         }
 210         state->smb2req = smb2req;
 211         state->status = NT_STATUS_INTERNAL_ERROR;
 212         state->out_output_buffer = data_blob_null;
 213         state->im = NULL;
 214
 215         DEBUG(10,("smbd_smb2_notify_send: file_id[0x%016llX]\n",
 216                   (unsigned long long)in_file_id_volatile));
 217
 218         smbreq = smbd_smb2_fake_smb_request(smb2req);
 219         if (tevent_req_nomem(smbreq, req)) {
 220                 return tevent_req_post(req, ev);
 221         }
 222
 223         state->smbreq = smbreq;
 224         smbreq->async_priv = (void *)req;
 225
 226         fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
 227         if (fsp == NULL) {
 228                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 229                 return tevent_req_post(req, ev);
 230         }
 231         if (conn != fsp->conn) {
 232                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 233                 return tevent_req_post(req, ev);
 234         }
 235         if (smb2req->session->compat->vuid != fsp->vuid) {
 236                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 237                 return tevent_req_post(req, ev);
 238         }
 239
 240         {
 241                 char *filter_string;
 242
 243                 filter_string = notify_filter_string(NULL, in_completion_filter);
 244                 if (tevent_req_nomem(filter_string, req)) {
 245                         return tevent_req_post(req, ev);
 246                 }
 247
 248                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 249                          "called on %s, filter = %s, recursive = %d\n",
 250                          fsp_str_dbg(fsp), filter_string, recursive));
 251
 252                 TALLOC_FREE(filter_string);
 253         }
 254
 255         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 256                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 257                 return tevent_req_post(req, ev);
 258         }
 259
 260         if (fsp->notify == NULL) {
 261
 262                 status = change_notify_create(fsp,
 263                                               in_completion_filter,
 264                                               recursive);
 265                 if (!NT_STATUS_IS_OK(status)) {
 266                         DEBUG(10, ("change_notify_create returned %s\n",
 267                                    nt_errstr(status)));
 268                         tevent_req_nterror(req, status);
 269                         return tevent_req_post(req, ev);
 270                 }
 271         }
 272
 273         if (fsp->notify->num_changes != 0) {
 274
 275                 /*
 276                  * We've got changes pending, respond immediately
 277                  */
 278
 279                 /*
 280                  * TODO: write a torture test to check the filtering behaviour
 281                  * here.
 282                  */
 283
 284                 change_notify_reply(smbreq,
 285                                     NT_STATUS_OK,
 286                                     in_output_buffer_length,
 287                                     fsp->notify,
 288                                     smbd_smb2_notify_reply);
 289
 290                 /*
 291                  * change_notify_reply() above has independently
 292                  * called tevent_req_done().
 293                  */
 294                 return tevent_req_post(req, ev);
 295         }
 296
 297         state->im = tevent_create_immediate(state);
 298         if (tevent_req_nomem(state->im, req)) {
 299                 return tevent_req_post(req, ev);
 300         }
 301
 302         /*
 303          * No changes pending, queue the request
 304          */
 305
 306         status = change_notify_add_request(smbreq,
 307                         in_output_buffer_length,
 308                         in_completion_filter,
 309                         recursive, fsp,
 310                         smbd_smb2_notify_reply);
 311         if (!NT_STATUS_IS_OK(status)) {
 312                 tevent_req_nterror(req, status);
 313                 return tevent_req_post(req, ev);
 314         }
 315
 316         /* allow this request to be canceled */
 317         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 318
 319         return req;
 320 }
 321
 322 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 323                                    NTSTATUS error_code,
 324                                    uint8_t *buf, size_t len)
 325 {
 326         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 327                                                        struct tevent_req);
 328         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 329                                                struct smbd_smb2_notify_state);
 330
 331         state->status = error_code;
 332         if (!NT_STATUS_IS_OK(error_code)) {
 333                 /* nothing */
 334         } else if (len == 0) {
 335                 state->status = STATUS_NOTIFY_ENUM_DIR;
 336         } else {
 337                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 338                 if (state->out_output_buffer.data == NULL) {
 339                         state->status = NT_STATUS_NO_MEMORY;
 340                 }
 341         }
 342
 343         if (state->im == NULL) {
 344                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 345                 return;
 346         }
 347
 348         /*
 349          * if this is called async, we need to go via an immediate event
 350          * because the caller replies on the smb_request (a child of req
 351          * being arround after calling this function
 352          */
 353         tevent_schedule_immediate(state->im,
 354                                   state->smb2req->sconn->ev_ctx,
 355                                   smbd_smb2_notify_reply_trigger,
 356                                   req);
 357 }
 358
 359 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 360                                            struct tevent_immediate *im,
 361                                            void *private_data)
 362 {
 363         struct tevent_req *req = talloc_get_type_abort(private_data,
 364                                                        struct tevent_req);
 365         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 366                                                struct smbd_smb2_notify_state);
 367
 368         if (!NT_STATUS_IS_OK(state->status)) {
 369                 tevent_req_nterror(req, state->status);
 370                 return;
 371         }
 372
 373         tevent_req_done(req);
 374 }
 375
 376 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 377 {
 378         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 379                                                struct smbd_smb2_notify_state);
 380
 381         smbd_notify_cancel_by_smbreq(state->smbreq);
 382
 383         state->smb2req->cancelled = true;
 384         tevent_req_done(req);
 385         return true;
 386 }
 387
 388 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 389                                       TALLOC_CTX *mem_ctx,
 390                                       DATA_BLOB *out_output_buffer)
 391 {
 392         NTSTATUS status;
 393         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 394                                                struct smbd_smb2_notify_state);
 395
 396         if (tevent_req_is_nterror(req, &status)) {
 397                 tevent_req_received(req);
 398                 return status;
 399         }
 400
 401         *out_output_buffer = state->out_output_buffer;
 402         talloc_steal(mem_ctx, out_output_buffer->data);
 403
 404         tevent_req_received(req);
 405         return NT_STATUS_OK;
 406 }