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         status = smbd_smb2_request_verify_creditcharge(req,
  82                                                 in_output_buffer_length);
  83
  84         if (!NT_STATUS_IS_OK(status)) {
  85                 return smbd_smb2_request_error(req, status);
  86         }
  87
  88         in_fsp = file_fsp_smb2(req, in_file_id_persistent, in_file_id_volatile);
  89         if (in_fsp == NULL) {
  90                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  91         }
  92
  93         subreq = smbd_smb2_notify_send(req, req->sconn->ev_ctx,
  94                                        req, in_fsp,
  95                                        in_flags,
  96                                        in_output_buffer_length,
  97                                        in_completion_filter);
  98         if (subreq == NULL) {
  99                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 100         }
 101         tevent_req_set_callback(subreq, smbd_smb2_request_notify_done, req);
 102
 103         return smbd_smb2_request_pending_queue(req, subreq, 500);
 104 }
 105
 106 static void smbd_smb2_request_notify_done(struct tevent_req *subreq)
 107 {
 108         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 109                                         struct smbd_smb2_request);
 110         int i = req->current_idx;
 111         DATA_BLOB outbody;
 112         DATA_BLOB outdyn;
 113         uint16_t out_output_buffer_offset;
 114         DATA_BLOB out_output_buffer = data_blob_null;
 115         NTSTATUS status;
 116         NTSTATUS error; /* transport error */
 117
 118         if (req->cancelled) {
 119                 struct smbd_smb2_notify_state *state = tevent_req_data(subreq,
 120                                                struct smbd_smb2_notify_state);
 121                 const uint8_t *inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 122                 uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
 123
 124                 DEBUG(10,("smbd_smb2_request_notify_done: cancelled mid %llu\n",
 125                         (unsigned long long)mid ));
 126                 error = smbd_smb2_request_error(req, NT_STATUS_CANCELLED);
 127                 if (!NT_STATUS_IS_OK(error)) {
 128                         smbd_server_connection_terminate(req->sconn,
 129                                 nt_errstr(error));
 130                         return;
 131                 }
 132                 TALLOC_FREE(state->im);
 133                 return;
 134         }
 135
 136         status = smbd_smb2_notify_recv(subreq,
 137                                        req,
 138                                        &out_output_buffer);
 139         TALLOC_FREE(subreq);
 140         if (!NT_STATUS_IS_OK(status)) {
 141                 error = smbd_smb2_request_error(req, status);
 142                 if (!NT_STATUS_IS_OK(error)) {
 143                         smbd_server_connection_terminate(req->sconn,
 144                                                          nt_errstr(error));
 145                         return;
 146                 }
 147                 return;
 148         }
 149
 150         out_output_buffer_offset = SMB2_HDR_BODY + 0x08;
 151
 152         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 153         if (outbody.data == NULL) {
 154                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 155                 if (!NT_STATUS_IS_OK(error)) {
 156                         smbd_server_connection_terminate(req->sconn,
 157                                                          nt_errstr(error));
 158                         return;
 159                 }
 160                 return;
 161         }
 162
 163         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 164         SSVAL(outbody.data, 0x02,
 165               out_output_buffer_offset);        /* output buffer offset */
 166         SIVAL(outbody.data, 0x04,
 167               out_output_buffer.length);        /* output buffer length */
 168
 169         outdyn = out_output_buffer;
 170
 171         error = smbd_smb2_request_done(req, outbody, &outdyn);
 172         if (!NT_STATUS_IS_OK(error)) {
 173                 smbd_server_connection_terminate(req->sconn,
 174                                                  nt_errstr(error));
 175                 return;
 176         }
 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                                                 struct files_struct *fsp,
 191                                                 uint16_t in_flags,
 192                                                 uint32_t in_output_buffer_length,
 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         bool recursive = (in_flags & SMB2_WATCH_TREE) ? true : false;
 200         NTSTATUS status;
 201
 202         req = tevent_req_create(mem_ctx, &state,
 203                                 struct smbd_smb2_notify_state);
 204         if (req == NULL) {
 205                 return NULL;
 206         }
 207         state->smb2req = smb2req;
 208         state->status = NT_STATUS_INTERNAL_ERROR;
 209         state->out_output_buffer = data_blob_null;
 210         state->im = NULL;
 211
 212         DEBUG(10,("smbd_smb2_notify_send: %s - %s\n",
 213                   fsp_str_dbg(fsp), fsp_fnum_dbg(fsp)));
 214
 215         smbreq = smbd_smb2_fake_smb_request(smb2req);
 216         if (tevent_req_nomem(smbreq, req)) {
 217                 return tevent_req_post(req, ev);
 218         }
 219
 220         state->smbreq = smbreq;
 221         smbreq->async_priv = (void *)req;
 222
 223         {
 224                 char *filter_string;
 225
 226                 filter_string = notify_filter_string(NULL, in_completion_filter);
 227                 if (tevent_req_nomem(filter_string, req)) {
 228                         return tevent_req_post(req, ev);
 229                 }
 230
 231                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 232                          "called on %s, filter = %s, recursive = %d\n",
 233                          fsp_str_dbg(fsp), filter_string, recursive));
 234
 235                 TALLOC_FREE(filter_string);
 236         }
 237
 238         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 239                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 240                 return tevent_req_post(req, ev);
 241         }
 242
 243         if (fsp->notify == NULL) {
 244
 245                 status = change_notify_create(fsp,
 246                                               in_completion_filter,
 247                                               recursive);
 248                 if (!NT_STATUS_IS_OK(status)) {
 249                         DEBUG(10, ("change_notify_create returned %s\n",
 250                                    nt_errstr(status)));
 251                         tevent_req_nterror(req, status);
 252                         return tevent_req_post(req, ev);
 253                 }
 254         }
 255
 256         if (change_notify_fsp_has_changes(fsp)) {
 257
 258                 /*
 259                  * We've got changes pending, respond immediately
 260                  */
 261
 262                 /*
 263                  * TODO: write a torture test to check the filtering behaviour
 264                  * here.
 265                  */
 266
 267                 change_notify_reply(smbreq,
 268                                     NT_STATUS_OK,
 269                                     in_output_buffer_length,
 270                                     fsp->notify,
 271                                     smbd_smb2_notify_reply);
 272
 273                 /*
 274                  * change_notify_reply() above has independently
 275                  * called tevent_req_done().
 276                  */
 277                 return tevent_req_post(req, ev);
 278         }
 279
 280         state->im = tevent_create_immediate(state);
 281         if (tevent_req_nomem(state->im, req)) {
 282                 return tevent_req_post(req, ev);
 283         }
 284
 285         /*
 286          * No changes pending, queue the request
 287          */
 288
 289         status = change_notify_add_request(smbreq,
 290                         in_output_buffer_length,
 291                         in_completion_filter,
 292                         recursive, fsp,
 293                         smbd_smb2_notify_reply);
 294         if (!NT_STATUS_IS_OK(status)) {
 295                 tevent_req_nterror(req, status);
 296                 return tevent_req_post(req, ev);
 297         }
 298
 299         /* allow this request to be canceled */
 300         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 301
 302         return req;
 303 }
 304
 305 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 306                                    NTSTATUS error_code,
 307                                    uint8_t *buf, size_t len)
 308 {
 309         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 310                                                        struct tevent_req);
 311         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 312                                                struct smbd_smb2_notify_state);
 313
 314         state->status = error_code;
 315         if (!NT_STATUS_IS_OK(error_code)) {
 316                 /* nothing */
 317         } else if (len == 0) {
 318                 state->status = STATUS_NOTIFY_ENUM_DIR;
 319         } else {
 320                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 321                 if (state->out_output_buffer.data == NULL) {
 322                         state->status = NT_STATUS_NO_MEMORY;
 323                 }
 324         }
 325
 326         if (state->im == NULL) {
 327                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 328                 return;
 329         }
 330
 331         /*
 332          * if this is called async, we need to go via an immediate event
 333          * because the caller replies on the smb_request (a child of req
 334          * being arround after calling this function
 335          */
 336         tevent_schedule_immediate(state->im,
 337                                   state->smb2req->sconn->ev_ctx,
 338                                   smbd_smb2_notify_reply_trigger,
 339                                   req);
 340 }
 341
 342 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 343                                            struct tevent_immediate *im,
 344                                            void *private_data)
 345 {
 346         struct tevent_req *req = talloc_get_type_abort(private_data,
 347                                                        struct tevent_req);
 348         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 349                                                struct smbd_smb2_notify_state);
 350
 351         if (!NT_STATUS_IS_OK(state->status)) {
 352                 tevent_req_nterror(req, state->status);
 353                 return;
 354         }
 355
 356         tevent_req_done(req);
 357 }
 358
 359 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 360 {
 361         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 362                                                struct smbd_smb2_notify_state);
 363
 364         smbd_notify_cancel_by_smbreq(state->smbreq);
 365
 366         state->smb2req->cancelled = true;
 367         tevent_req_done(req);
 368         return true;
 369 }
 370
 371 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 372                                       TALLOC_CTX *mem_ctx,
 373                                       DATA_BLOB *out_output_buffer)
 374 {
 375         NTSTATUS status;
 376         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 377                                                struct smbd_smb2_notify_state);
 378
 379         if (tevent_req_is_nterror(req, &status)) {
 380                 tevent_req_received(req);
 381                 return status;
 382         }
 383
 384         *out_output_buffer = state->out_output_buffer;
 385         talloc_steal(mem_ctx, out_output_buffer->data);
 386
 387         tevent_req_received(req);
 388         return NT_STATUS_OK;
 389 }