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         if (req->compat_chain_fsp) {
  81                 /* skip check */
  82         } else if (in_file_id_persistent != in_file_id_volatile) {
  83                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  84         }
  85
  86         subreq = smbd_smb2_notify_send(req,
  87                                        req->sconn->ev_ctx,
  88                                        req,
  89                                        in_flags,
  90                                        in_output_buffer_length,
  91                                        in_file_id_volatile,
  92                                        in_completion_filter);
  93         if (subreq == NULL) {
  94                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
  95         }
  96         tevent_req_set_callback(subreq, smbd_smb2_request_notify_done, req);
  97
  98         return smbd_smb2_request_pending_queue(req, subreq, 500);
  99 }
 100
 101 static void smbd_smb2_request_notify_done(struct tevent_req *subreq)
 102 {
 103         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 104                                         struct smbd_smb2_request);
 105         int i = req->current_idx;
 106         DATA_BLOB outbody;
 107         DATA_BLOB outdyn;
 108         uint16_t out_output_buffer_offset;
 109         DATA_BLOB out_output_buffer = data_blob_null;
 110         NTSTATUS status;
 111         NTSTATUS error; /* transport error */
 112
 113         if (req->cancelled) {
 114                 struct smbd_smb2_notify_state *state = tevent_req_data(subreq,
 115                                                struct smbd_smb2_notify_state);
 116                 const uint8_t *inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 117                 uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
 118
 119                 DEBUG(10,("smbd_smb2_request_notify_done: cancelled mid %llu\n",
 120                         (unsigned long long)mid ));
 121                 error = smbd_smb2_request_error(req, NT_STATUS_CANCELLED);
 122                 if (!NT_STATUS_IS_OK(error)) {
 123                         smbd_server_connection_terminate(req->sconn,
 124                                 nt_errstr(error));
 125                         return;
 126                 }
 127                 TALLOC_FREE(state->im);
 128                 return;
 129         }
 130
 131         status = smbd_smb2_notify_recv(subreq,
 132                                        req,
 133                                        &out_output_buffer);
 134         TALLOC_FREE(subreq);
 135         if (!NT_STATUS_IS_OK(status)) {
 136                 error = smbd_smb2_request_error(req, status);
 137                 if (!NT_STATUS_IS_OK(error)) {
 138                         smbd_server_connection_terminate(req->sconn,
 139                                                          nt_errstr(error));
 140                         return;
 141                 }
 142                 return;
 143         }
 144
 145         out_output_buffer_offset = SMB2_HDR_BODY + 0x08;
 146
 147         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 148         if (outbody.data == NULL) {
 149                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 150                 if (!NT_STATUS_IS_OK(error)) {
 151                         smbd_server_connection_terminate(req->sconn,
 152                                                          nt_errstr(error));
 153                         return;
 154                 }
 155                 return;
 156         }
 157
 158         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 159         SSVAL(outbody.data, 0x02,
 160               out_output_buffer_offset);        /* output buffer offset */
 161         SIVAL(outbody.data, 0x04,
 162               out_output_buffer.length);        /* output buffer length */
 163
 164         outdyn = out_output_buffer;
 165
 166         error = smbd_smb2_request_done(req, outbody, &outdyn);
 167         if (!NT_STATUS_IS_OK(error)) {
 168                 smbd_server_connection_terminate(req->sconn,
 169                                                  nt_errstr(error));
 170                 return;
 171         }
 172 }
 173
 174 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 175                                    NTSTATUS error_code,
 176                                    uint8_t *buf, size_t len);
 177 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 178                                            struct tevent_immediate *im,
 179                                            void *private_data);
 180 static bool smbd_smb2_notify_cancel(struct tevent_req *req);
 181
 182 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
 183                                                 struct tevent_context *ev,
 184                                                 struct smbd_smb2_request *smb2req,
 185                                                 uint16_t in_flags,
 186                                                 uint32_t in_output_buffer_length,
 187                                                 uint64_t in_file_id_volatile,
 188                                                 uint64_t in_completion_filter)
 189 {
 190         struct tevent_req *req;
 191         struct smbd_smb2_notify_state *state;
 192         struct smb_request *smbreq;
 193         connection_struct *conn = smb2req->tcon->compat_conn;
 194         files_struct *fsp;
 195         bool recursive = (in_flags & SMB2_WATCH_TREE) ? 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: file_id[0x%016llX]\n",
 209                   (unsigned long long)in_file_id_volatile));
 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         fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
 220         if (fsp == NULL) {
 221                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 222                 return tevent_req_post(req, ev);
 223         }
 224         if (conn != fsp->conn) {
 225                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 226                 return tevent_req_post(req, ev);
 227         }
 228         if (smb2req->session->vuid != fsp->vuid) {
 229                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 230                 return tevent_req_post(req, ev);
 231         }
 232
 233         {
 234                 char *filter_string;
 235
 236                 filter_string = notify_filter_string(NULL, in_completion_filter);
 237                 if (tevent_req_nomem(filter_string, req)) {
 238                         return tevent_req_post(req, ev);
 239                 }
 240
 241                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 242                          "called on %s, filter = %s, recursive = %d\n",
 243                          fsp_str_dbg(fsp), filter_string, recursive));
 244
 245                 TALLOC_FREE(filter_string);
 246         }
 247
 248         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 249                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 250                 return tevent_req_post(req, ev);
 251         }
 252
 253         if (fsp->notify == NULL) {
 254
 255                 status = change_notify_create(fsp,
 256                                               in_completion_filter,
 257                                               recursive);
 258                 if (!NT_STATUS_IS_OK(status)) {
 259                         DEBUG(10, ("change_notify_create returned %s\n",
 260                                    nt_errstr(status)));
 261                         tevent_req_nterror(req, status);
 262                         return tevent_req_post(req, ev);
 263                 }
 264         }
 265
 266         if (fsp->notify->num_changes != 0) {
 267
 268                 /*
 269                  * We've got changes pending, respond immediately
 270                  */
 271
 272                 /*
 273                  * TODO: write a torture test to check the filtering behaviour
 274                  * here.
 275                  */
 276
 277                 change_notify_reply(smbreq,
 278                                     NT_STATUS_OK,
 279                                     in_output_buffer_length,
 280                                     fsp->notify,
 281                                     smbd_smb2_notify_reply);
 282
 283                 /*
 284                  * change_notify_reply() above has independently
 285                  * called tevent_req_done().
 286                  */
 287                 return tevent_req_post(req, ev);
 288         }
 289
 290         state->im = tevent_create_immediate(state);
 291         if (tevent_req_nomem(state->im, req)) {
 292                 return tevent_req_post(req, ev);
 293         }
 294
 295         /*
 296          * No changes pending, queue the request
 297          */
 298
 299         status = change_notify_add_request(smbreq,
 300                         in_output_buffer_length,
 301                         in_completion_filter,
 302                         recursive, fsp,
 303                         smbd_smb2_notify_reply);
 304         if (!NT_STATUS_IS_OK(status)) {
 305                 tevent_req_nterror(req, status);
 306                 return tevent_req_post(req, ev);
 307         }
 308
 309         /* allow this request to be canceled */
 310         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 311
 312         return req;
 313 }
 314
 315 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 316                                    NTSTATUS error_code,
 317                                    uint8_t *buf, size_t len)
 318 {
 319         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 320                                                        struct tevent_req);
 321         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 322                                                struct smbd_smb2_notify_state);
 323
 324         state->status = error_code;
 325         if (!NT_STATUS_IS_OK(error_code)) {
 326                 /* nothing */
 327         } else if (len == 0) {
 328                 state->status = STATUS_NOTIFY_ENUM_DIR;
 329         } else {
 330                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 331                 if (state->out_output_buffer.data == NULL) {
 332                         state->status = NT_STATUS_NO_MEMORY;
 333                 }
 334         }
 335
 336         if (state->im == NULL) {
 337                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 338                 return;
 339         }
 340
 341         /*
 342          * if this is called async, we need to go via an immediate event
 343          * because the caller replies on the smb_request (a child of req
 344          * being arround after calling this function
 345          */
 346         tevent_schedule_immediate(state->im,
 347                                   state->smb2req->sconn->ev_ctx,
 348                                   smbd_smb2_notify_reply_trigger,
 349                                   req);
 350 }
 351
 352 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 353                                            struct tevent_immediate *im,
 354                                            void *private_data)
 355 {
 356         struct tevent_req *req = talloc_get_type_abort(private_data,
 357                                                        struct tevent_req);
 358         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 359                                                struct smbd_smb2_notify_state);
 360
 361         if (!NT_STATUS_IS_OK(state->status)) {
 362                 tevent_req_nterror(req, state->status);
 363                 return;
 364         }
 365
 366         tevent_req_done(req);
 367 }
 368
 369 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 370 {
 371         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 372                                                struct smbd_smb2_notify_state);
 373
 374         smbd_notify_cancel_by_smbreq(state->smbreq);
 375
 376         state->smb2req->cancelled = true;
 377         tevent_req_done(req);
 378         return true;
 379 }
 380
 381 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 382                                       TALLOC_CTX *mem_ctx,
 383                                       DATA_BLOB *out_output_buffer)
 384 {
 385         NTSTATUS status;
 386         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 387                                                struct smbd_smb2_notify_state);
 388
 389         if (tevent_req_is_nterror(req, &status)) {
 390                 tevent_req_received(req);
 391                 return status;
 392         }
 393
 394         *out_output_buffer = state->out_output_buffer;
 395         talloc_steal(mem_ctx, out_output_buffer->data);
 396
 397         tevent_req_received(req);
 398         return NT_STATUS_OK;
 399 }