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
  27 struct smbd_smb2_notify_state {
  28         struct smbd_smb2_request *smb2req;
  29         struct smb_request *smbreq;
  30         struct tevent_immediate *im;
  31         NTSTATUS status;
  32         DATA_BLOB out_output_buffer;
  33 };
  34
  35 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
  36                                                 struct tevent_context *ev,
  37                                                 struct smbd_smb2_request *smb2req,
  38                                                 uint16_t in_flags,
  39                                                 uint32_t in_output_buffer_length,
  40                                                 uint64_t in_file_id_volatile,
  41                                                 uint64_t in_completion_filter);
  42 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
  43                                       TALLOC_CTX *mem_ctx,
  44                                       DATA_BLOB *out_output_buffer);
  45
  46 static void smbd_smb2_request_notify_done(struct tevent_req *subreq);
  47 NTSTATUS smbd_smb2_request_process_notify(struct smbd_smb2_request *req)
  48 {
  49         const uint8_t *inhdr;
  50         const uint8_t *inbody;
  51         int i = req->current_idx;
  52         size_t expected_body_size = 0x20;
  53         size_t body_size;
  54         uint16_t in_flags;
  55         uint32_t in_output_buffer_length;
  56         uint64_t in_file_id_persistent;
  57         uint64_t in_file_id_volatile;
  58         uint64_t in_completion_filter;
  59         struct tevent_req *subreq;
  60
  61         inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
  62         if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
  63                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  64         }
  65
  66         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  67
  68         body_size = SVAL(inbody, 0x00);
  69         if (body_size != expected_body_size) {
  70                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  71         }
  72
  73         in_flags                = SVAL(inbody, 0x02);
  74         in_output_buffer_length = IVAL(inbody, 0x04);
  75         in_file_id_persistent   = BVAL(inbody, 0x08);
  76         in_file_id_volatile     = BVAL(inbody, 0x10);
  77         in_completion_filter    = IVAL(inbody, 0x18);
  78
  79         /*
  80          * 0x00010000 is what Windows 7 uses,
  81          * Windows 2008 uses 0x00080000
  82          */
  83         if (in_output_buffer_length > lp_smb2_max_trans()) {
  84                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  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->smb2.event_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);
 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         uint8_t *outhdr;
 114         DATA_BLOB outbody;
 115         DATA_BLOB outdyn;
 116         uint16_t out_output_buffer_offset;
 117         DATA_BLOB out_output_buffer = data_blob_null;
 118         NTSTATUS status;
 119         NTSTATUS error; /* transport error */
 120
 121         if (req->cancelled) {
 122                 struct smbd_smb2_notify_state *state = tevent_req_data(subreq,
 123                                                struct smbd_smb2_notify_state);
 124                 const uint8_t *inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 125                 uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
 126
 127                 DEBUG(10,("smbd_smb2_request_notify_done: cancelled mid %llu\n",
 128                         (unsigned long long)mid ));
 129                 error = smbd_smb2_request_error(req, NT_STATUS_CANCELLED);
 130                 if (!NT_STATUS_IS_OK(error)) {
 131                         smbd_server_connection_terminate(req->sconn,
 132                                 nt_errstr(error));
 133                         return;
 134                 }
 135                 TALLOC_FREE(state->im);
 136                 return;
 137         }
 138
 139         status = smbd_smb2_notify_recv(subreq,
 140                                        req,
 141                                        &out_output_buffer);
 142         TALLOC_FREE(subreq);
 143         if (!NT_STATUS_IS_OK(status)) {
 144                 error = smbd_smb2_request_error(req, status);
 145                 if (!NT_STATUS_IS_OK(error)) {
 146                         smbd_server_connection_terminate(req->sconn,
 147                                                          nt_errstr(error));
 148                         return;
 149                 }
 150                 return;
 151         }
 152
 153         out_output_buffer_offset = SMB2_HDR_BODY + 0x08;
 154
 155         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 156
 157         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 158         if (outbody.data == NULL) {
 159                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 160                 if (!NT_STATUS_IS_OK(error)) {
 161                         smbd_server_connection_terminate(req->sconn,
 162                                                          nt_errstr(error));
 163                         return;
 164                 }
 165                 return;
 166         }
 167
 168         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 169         SSVAL(outbody.data, 0x02,
 170               out_output_buffer_offset);        /* output buffer offset */
 171         SIVAL(outbody.data, 0x04,
 172               out_output_buffer.length);        /* output buffer length */
 173
 174         outdyn = out_output_buffer;
 175
 176         error = smbd_smb2_request_done(req, outbody, &outdyn);
 177         if (!NT_STATUS_IS_OK(error)) {
 178                 smbd_server_connection_terminate(req->sconn,
 179                                                  nt_errstr(error));
 180                 return;
 181         }
 182 }
 183
 184 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 185                                    NTSTATUS error_code,
 186                                    uint8_t *buf, size_t len);
 187 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 188                                            struct tevent_immediate *im,
 189                                            void *private_data);
 190 static bool smbd_smb2_notify_cancel(struct tevent_req *req);
 191
 192 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
 193                                                 struct tevent_context *ev,
 194                                                 struct smbd_smb2_request *smb2req,
 195                                                 uint16_t in_flags,
 196                                                 uint32_t in_output_buffer_length,
 197                                                 uint64_t in_file_id_volatile,
 198                                                 uint64_t in_completion_filter)
 199 {
 200         struct tevent_req *req;
 201         struct smbd_smb2_notify_state *state;
 202         struct smb_request *smbreq;
 203         connection_struct *conn = smb2req->tcon->compat_conn;
 204         files_struct *fsp;
 205         bool recursive = (in_flags & 0x0001) ? true : false;
 206         NTSTATUS status;
 207
 208         req = tevent_req_create(mem_ctx, &state,
 209                                 struct smbd_smb2_notify_state);
 210         if (req == NULL) {
 211                 return NULL;
 212         }
 213         state->smb2req = smb2req;
 214         state->status = NT_STATUS_INTERNAL_ERROR;
 215         state->out_output_buffer = data_blob_null;
 216         state->im = NULL;
 217
 218         DEBUG(10,("smbd_smb2_notify_send: file_id[0x%016llX]\n",
 219                   (unsigned long long)in_file_id_volatile));
 220
 221         smbreq = smbd_smb2_fake_smb_request(smb2req);
 222         if (tevent_req_nomem(smbreq, req)) {
 223                 return tevent_req_post(req, ev);
 224         }
 225
 226         state->smbreq = smbreq;
 227         smbreq->async_priv = (void *)req;
 228
 229         fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
 230         if (fsp == NULL) {
 231                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 232                 return tevent_req_post(req, ev);
 233         }
 234         if (conn != fsp->conn) {
 235                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 236                 return tevent_req_post(req, ev);
 237         }
 238         if (smb2req->session->vuid != fsp->vuid) {
 239                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 240                 return tevent_req_post(req, ev);
 241         }
 242
 243         {
 244                 char *filter_string;
 245
 246                 filter_string = notify_filter_string(NULL, in_completion_filter);
 247                 if (tevent_req_nomem(filter_string, req)) {
 248                         return tevent_req_post(req, ev);
 249                 }
 250
 251                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 252                          "called on %s, filter = %s, recursive = %d\n",
 253                          fsp_str_dbg(fsp), filter_string, recursive));
 254
 255                 TALLOC_FREE(filter_string);
 256         }
 257
 258         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 259                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 260                 return tevent_req_post(req, ev);
 261         }
 262
 263         if (fsp->notify == NULL) {
 264
 265                 status = change_notify_create(fsp,
 266                                               in_completion_filter,
 267                                               recursive);
 268                 if (!NT_STATUS_IS_OK(status)) {
 269                         DEBUG(10, ("change_notify_create returned %s\n",
 270                                    nt_errstr(status)));
 271                         tevent_req_nterror(req, status);
 272                         return tevent_req_post(req, ev);
 273                 }
 274         }
 275
 276         if (fsp->notify->num_changes != 0) {
 277
 278                 /*
 279                  * We've got changes pending, respond immediately
 280                  */
 281
 282                 /*
 283                  * TODO: write a torture test to check the filtering behaviour
 284                  * here.
 285                  */
 286
 287                 change_notify_reply(smbreq,
 288                                     NT_STATUS_OK,
 289                                     in_output_buffer_length,
 290                                     fsp->notify,
 291                                     smbd_smb2_notify_reply);
 292
 293                 /*
 294                  * change_notify_reply() above has independently
 295                  * called tevent_req_done().
 296                  */
 297                 return tevent_req_post(req, ev);
 298         }
 299
 300         state->im = tevent_create_immediate(state);
 301         if (tevent_req_nomem(state->im, req)) {
 302                 return tevent_req_post(req, ev);
 303         }
 304
 305         /*
 306          * No changes pending, queue the request
 307          */
 308
 309         status = change_notify_add_request(smbreq,
 310                         in_output_buffer_length,
 311                         in_completion_filter,
 312                         recursive, fsp,
 313                         smbd_smb2_notify_reply);
 314         if (!NT_STATUS_IS_OK(status)) {
 315                 tevent_req_nterror(req, status);
 316                 return tevent_req_post(req, ev);
 317         }
 318
 319         /* allow this request to be canceled */
 320         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 321
 322         return req;
 323 }
 324
 325 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 326                                    NTSTATUS error_code,
 327                                    uint8_t *buf, size_t len)
 328 {
 329         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 330                                                        struct tevent_req);
 331         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 332                                                struct smbd_smb2_notify_state);
 333
 334         state->status = error_code;
 335         if (!NT_STATUS_IS_OK(error_code)) {
 336                 /* nothing */
 337         } else if (len == 0) {
 338                 state->status = STATUS_NOTIFY_ENUM_DIR;
 339         } else {
 340                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 341                 if (state->out_output_buffer.data == NULL) {
 342                         state->status = NT_STATUS_NO_MEMORY;
 343                 }
 344         }
 345
 346         if (state->im == NULL) {
 347                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 348                 return;
 349         }
 350
 351         /*
 352          * if this is called async, we need to go via an immediate event
 353          * because the caller replies on the smb_request (a child of req
 354          * being arround after calling this function
 355          */
 356         tevent_schedule_immediate(state->im,
 357                                   state->smb2req->sconn->smb2.event_ctx,
 358                                   smbd_smb2_notify_reply_trigger,
 359                                   req);
 360 }
 361
 362 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 363                                            struct tevent_immediate *im,
 364                                            void *private_data)
 365 {
 366         struct tevent_req *req = talloc_get_type_abort(private_data,
 367                                                        struct tevent_req);
 368         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 369                                                struct smbd_smb2_notify_state);
 370
 371         if (!NT_STATUS_IS_OK(state->status)) {
 372                 tevent_req_nterror(req, state->status);
 373                 return;
 374         }
 375
 376         tevent_req_done(req);
 377 }
 378
 379 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 380 {
 381         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 382                                                struct smbd_smb2_notify_state);
 383
 384         smbd_notify_cancel_by_smbreq(state->smbreq);
 385
 386         state->smb2req->cancelled = true;
 387         tevent_req_done(req);
 388         return true;
 389 }
 390
 391 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 392                                       TALLOC_CTX *mem_ctx,
 393                                       DATA_BLOB *out_output_buffer)
 394 {
 395         NTSTATUS status;
 396         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 397                                                struct smbd_smb2_notify_state);
 398
 399         if (tevent_req_is_nterror(req, &status)) {
 400                 tevent_req_received(req);
 401                 return status;
 402         }
 403
 404         *out_output_buffer = state->out_output_buffer;
 405         talloc_steal(mem_ctx, out_output_buffer->data);
 406
 407         tevent_req_received(req);
 408         return NT_STATUS_OK;
 409 }