source3/smbd/smb2_notify.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Core SMB2 server
   4
   5    Copyright (C) Stefan Metzmacher 2009
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "smbd/globals.h"
  23 #include "../libcli/smb/smb_common.h"
  24
  25 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
  26                                                 struct tevent_context *ev,
  27                                                 struct smbd_smb2_request *smb2req,
  28                                                 uint16_t in_flags,
  29                                                 uint32_t in_output_buffer_length,
  30                                                 uint64_t in_file_id_volatile,
  31                                                 uint64_t in_completion_filter);
  32 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
  33                                       TALLOC_CTX *mem_ctx,
  34                                       DATA_BLOB *out_output_buffer);
  35
  36 static void smbd_smb2_request_notify_done(struct tevent_req *subreq);
  37 NTSTATUS smbd_smb2_request_process_notify(struct smbd_smb2_request *req)
  38 {
  39         const uint8_t *inhdr;
  40         const uint8_t *inbody;
  41         int i = req->current_idx;
  42         size_t expected_body_size = 0x20;
  43         size_t body_size;
  44         uint16_t in_flags;
  45         uint32_t in_output_buffer_length;
  46         uint64_t in_file_id_persistent;
  47         uint64_t in_file_id_volatile;
  48         uint64_t in_completion_filter;
  49         struct tevent_req *subreq;
  50
  51         inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
  52         if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
  53                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  54         }
  55
  56         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  57
  58         body_size = SVAL(inbody, 0x00);
  59         if (body_size != expected_body_size) {
  60                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  61         }
  62
  63         in_flags                = SVAL(inbody, 0x02);
  64         in_output_buffer_length = IVAL(inbody, 0x04);
  65         in_file_id_persistent   = BVAL(inbody, 0x08);
  66         in_file_id_volatile     = BVAL(inbody, 0x10);
  67         in_completion_filter    = IVAL(inbody, 0x18);
  68
  69         /*
  70          * 0x00010000 is what Windows 7 uses,
  71          * Windows 2008 uses 0x00080000
  72          */
  73         if (in_output_buffer_length > lp_smb2_max_trans()) {
  74                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  75         }
  76
  77         if (req->compat_chain_fsp) {
  78                 /* skip check */
  79         } else if (in_file_id_persistent != 0) {
  80                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  81         }
  82
  83         subreq = smbd_smb2_notify_send(req,
  84                                        req->sconn->smb2.event_ctx,
  85                                        req,
  86                                        in_flags,
  87                                        in_output_buffer_length,
  88                                        in_file_id_volatile,
  89                                        in_completion_filter);
  90         if (subreq == NULL) {
  91                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
  92         }
  93         tevent_req_set_callback(subreq, smbd_smb2_request_notify_done, req);
  94
  95         return smbd_smb2_request_pending_queue(req, subreq);
  96 }
  97
  98 static void smbd_smb2_request_notify_done(struct tevent_req *subreq)
  99 {
 100         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 101                                         struct smbd_smb2_request);
 102         int i = req->current_idx;
 103         uint8_t *outhdr;
 104         DATA_BLOB outbody;
 105         DATA_BLOB outdyn;
 106         uint16_t out_output_buffer_offset;
 107         DATA_BLOB out_output_buffer = data_blob_null;
 108         NTSTATUS status;
 109         NTSTATUS error; /* transport error */
 110
 111         if (req->cancelled) {
 112                 const uint8_t *inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 113                 uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
 114                 DEBUG(10,("smbd_smb2_request_notify_done: cancelled mid %llu\n",
 115                         (unsigned long long)mid ));
 116                 return;
 117         }
 118
 119         status = smbd_smb2_notify_recv(subreq,
 120                                        req,
 121                                        &out_output_buffer);
 122         TALLOC_FREE(subreq);
 123         if (!NT_STATUS_IS_OK(status)) {
 124                 error = smbd_smb2_request_error(req, status);
 125                 if (!NT_STATUS_IS_OK(error)) {
 126                         smbd_server_connection_terminate(req->sconn,
 127                                                          nt_errstr(error));
 128                         return;
 129                 }
 130                 return;
 131         }
 132
 133         out_output_buffer_offset = SMB2_HDR_BODY + 0x08;
 134
 135         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 136
 137         outbody = data_blob_talloc(req->out.vector, NULL, 0x08);
 138         if (outbody.data == NULL) {
 139                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 140                 if (!NT_STATUS_IS_OK(error)) {
 141                         smbd_server_connection_terminate(req->sconn,
 142                                                          nt_errstr(error));
 143                         return;
 144                 }
 145                 return;
 146         }
 147
 148         SSVAL(outbody.data, 0x00, 0x08 + 1);    /* struct size */
 149         SSVAL(outbody.data, 0x02,
 150               out_output_buffer_offset);        /* output buffer offset */
 151         SIVAL(outbody.data, 0x04,
 152               out_output_buffer.length);        /* output buffer length */
 153
 154         outdyn = out_output_buffer;
 155
 156         error = smbd_smb2_request_done(req, outbody, &outdyn);
 157         if (!NT_STATUS_IS_OK(error)) {
 158                 smbd_server_connection_terminate(req->sconn,
 159                                                  nt_errstr(error));
 160                 return;
 161         }
 162 }
 163
 164 struct smbd_smb2_notify_state {
 165         struct smbd_smb2_request *smb2req;
 166         struct smb_request *smbreq;
 167         struct tevent_immediate *im;
 168         NTSTATUS status;
 169         DATA_BLOB out_output_buffer;
 170 };
 171
 172 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 173                                    NTSTATUS error_code,
 174                                    uint8_t *buf, size_t len);
 175 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 176                                            struct tevent_immediate *im,
 177                                            void *private_data);
 178 static bool smbd_smb2_notify_cancel(struct tevent_req *req);
 179
 180 static struct tevent_req *smbd_smb2_notify_send(TALLOC_CTX *mem_ctx,
 181                                                 struct tevent_context *ev,
 182                                                 struct smbd_smb2_request *smb2req,
 183                                                 uint16_t in_flags,
 184                                                 uint32_t in_output_buffer_length,
 185                                                 uint64_t in_file_id_volatile,
 186                                                 uint64_t in_completion_filter)
 187 {
 188         struct tevent_req *req;
 189         struct smbd_smb2_notify_state *state;
 190         struct smb_request *smbreq;
 191         connection_struct *conn = smb2req->tcon->compat_conn;
 192         files_struct *fsp;
 193         bool recursive = (in_flags & 0x0001) ? true : false;
 194         NTSTATUS status;
 195
 196         req = tevent_req_create(mem_ctx, &state,
 197                                 struct smbd_smb2_notify_state);
 198         if (req == NULL) {
 199                 return NULL;
 200         }
 201         state->smb2req = smb2req;
 202         state->status = NT_STATUS_INTERNAL_ERROR;
 203         state->out_output_buffer = data_blob_null;
 204         state->im = NULL;
 205
 206         DEBUG(10,("smbd_smb2_notify_send: file_id[0x%016llX]\n",
 207                   (unsigned long long)in_file_id_volatile));
 208
 209         smbreq = smbd_smb2_fake_smb_request(smb2req);
 210         if (tevent_req_nomem(smbreq, req)) {
 211                 return tevent_req_post(req, ev);
 212         }
 213
 214         state->smbreq = smbreq;
 215         smbreq->async_priv = (void *)req;
 216
 217         fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
 218         if (fsp == NULL) {
 219                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 220                 return tevent_req_post(req, ev);
 221         }
 222         if (conn != fsp->conn) {
 223                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 224                 return tevent_req_post(req, ev);
 225         }
 226         if (smb2req->session->vuid != fsp->vuid) {
 227                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 228                 return tevent_req_post(req, ev);
 229         }
 230
 231         {
 232                 char *filter_string;
 233
 234                 filter_string = notify_filter_string(NULL, in_completion_filter);
 235                 if (tevent_req_nomem(filter_string, req)) {
 236                         return tevent_req_post(req, ev);
 237                 }
 238
 239                 DEBUG(3,("smbd_smb2_notify_send: notify change "
 240                          "called on %s, filter = %s, recursive = %d\n",
 241                          fsp_str_dbg(fsp), filter_string, recursive));
 242
 243                 TALLOC_FREE(filter_string);
 244         }
 245
 246         if ((!fsp->is_directory) || (conn != fsp->conn)) {
 247                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 248                 return tevent_req_post(req, ev);
 249         }
 250
 251         if (fsp->notify == NULL) {
 252
 253                 status = change_notify_create(fsp,
 254                                               in_completion_filter,
 255                                               recursive);
 256                 if (!NT_STATUS_IS_OK(status)) {
 257                         DEBUG(10, ("change_notify_create returned %s\n",
 258                                    nt_errstr(status)));
 259                         tevent_req_nterror(req, status);
 260                         return tevent_req_post(req, ev);
 261                 }
 262         }
 263
 264         if (fsp->notify->num_changes != 0) {
 265
 266                 /*
 267                  * We've got changes pending, respond immediately
 268                  */
 269
 270                 /*
 271                  * TODO: write a torture test to check the filtering behaviour
 272                  * here.
 273                  */
 274
 275                 change_notify_reply(fsp->conn, smbreq,
 276                                     NT_STATUS_OK,
 277                                     in_output_buffer_length,
 278                                     fsp->notify,
 279                                     smbd_smb2_notify_reply);
 280
 281                 /*
 282                  * change_notify_reply() above has independently
 283                  * called tevent_req_done().
 284                  */
 285                 return tevent_req_post(req, ev);
 286         }
 287
 288         state->im = tevent_create_immediate(state);
 289         if (tevent_req_nomem(state->im, req)) {
 290                 return tevent_req_post(req, ev);
 291         }
 292
 293         /*
 294          * No changes pending, queue the request
 295          */
 296
 297         status = change_notify_add_request(smbreq,
 298                         in_output_buffer_length,
 299                         in_completion_filter,
 300                         recursive, fsp,
 301                         smbd_smb2_notify_reply);
 302         if (!NT_STATUS_IS_OK(status)) {
 303                 tevent_req_nterror(req, status);
 304                 return tevent_req_post(req, ev);
 305         }
 306
 307         /* allow this request to be canceled */
 308         tevent_req_set_cancel_fn(req, smbd_smb2_notify_cancel);
 309
 310         return req;
 311 }
 312
 313 static void smbd_smb2_notify_reply(struct smb_request *smbreq,
 314                                    NTSTATUS error_code,
 315                                    uint8_t *buf, size_t len)
 316 {
 317         struct tevent_req *req = talloc_get_type_abort(smbreq->async_priv,
 318                                                        struct tevent_req);
 319         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 320                                                struct smbd_smb2_notify_state);
 321
 322         state->status = error_code;
 323         if (!NT_STATUS_IS_OK(error_code)) {
 324                 /* nothing */
 325         } else if (len == 0) {
 326                 state->status = STATUS_NOTIFY_ENUM_DIR;
 327         } else {
 328                 state->out_output_buffer = data_blob_talloc(state, buf, len);
 329                 if (state->out_output_buffer.data == NULL) {
 330                         state->status = NT_STATUS_NO_MEMORY;
 331                 }
 332         }
 333
 334         if (state->im == NULL) {
 335                 smbd_smb2_notify_reply_trigger(NULL, NULL, req);
 336                 return;
 337         }
 338
 339         /*
 340          * if this is called async, we need to go via an immediate event
 341          * because the caller replies on the smb_request (a child of req
 342          * being arround after calling this function
 343          */
 344         tevent_schedule_immediate(state->im,
 345                                   state->smb2req->sconn->smb2.event_ctx,
 346                                   smbd_smb2_notify_reply_trigger,
 347                                   req);
 348 }
 349
 350 static void smbd_smb2_notify_reply_trigger(struct tevent_context *ctx,
 351                                            struct tevent_immediate *im,
 352                                            void *private_data)
 353 {
 354         struct tevent_req *req = talloc_get_type_abort(private_data,
 355                                                        struct tevent_req);
 356         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 357                                                struct smbd_smb2_notify_state);
 358
 359         if (!NT_STATUS_IS_OK(state->status)) {
 360                 tevent_req_nterror(req, state->status);
 361                 return;
 362         }
 363
 364         tevent_req_done(req);
 365 }
 366
 367 static bool smbd_smb2_notify_cancel(struct tevent_req *req)
 368 {
 369         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 370                                                struct smbd_smb2_notify_state);
 371
 372         smbd_notify_cancel_by_smbreq(state->smb2req->sconn,
 373                                      state->smbreq);
 374
 375         state->smb2req->cancelled = true;
 376         tevent_req_done(req);
 377         return true;
 378 }
 379
 380 static NTSTATUS smbd_smb2_notify_recv(struct tevent_req *req,
 381                                       TALLOC_CTX *mem_ctx,
 382                                       DATA_BLOB *out_output_buffer)
 383 {
 384         NTSTATUS status;
 385         struct smbd_smb2_notify_state *state = tevent_req_data(req,
 386                                                struct smbd_smb2_notify_state);
 387
 388         if (tevent_req_is_nterror(req, &status)) {
 389                 tevent_req_received(req);
 390                 return status;
 391         }
 392
 393         *out_output_buffer = state->out_output_buffer;
 394         talloc_steal(mem_ctx, out_output_buffer->data);
 395
 396         tevent_req_received(req);
 397         return NT_STATUS_OK;
 398 }