source3/smbd/smb2_read.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_read_send(TALLOC_CTX *mem_ctx,
  26                                               struct tevent_context *ev,
  27                                               struct smbd_smb2_request *smb2req,
  28                                               uint32_t in_smbpid,
  29                                               uint64_t in_file_id_volatile,
  30                                               uint32_t in_length,
  31                                               uint64_t in_offset,
  32                                               uint32_t in_minimum,
  33                                               uint32_t in_remaining);
  34 static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req,
  35                                     TALLOC_CTX *mem_ctx,
  36                                     DATA_BLOB *out_data,
  37                                     uint32_t *out_remaining);
  38
  39 static void smbd_smb2_request_read_done(struct tevent_req *subreq);
  40 NTSTATUS smbd_smb2_request_process_read(struct smbd_smb2_request *req)
  41 {
  42         const uint8_t *inhdr;
  43         const uint8_t *inbody;
  44         int i = req->current_idx;
  45         size_t expected_body_size = 0x31;
  46         size_t body_size;
  47         uint32_t in_smbpid;
  48         uint32_t in_length;
  49         uint64_t in_offset;
  50         uint64_t in_file_id_persistent;
  51         uint64_t in_file_id_volatile;
  52         uint32_t in_minimum_count;
  53         uint32_t in_remaining_bytes;
  54         struct tevent_req *subreq;
  55
  56         inhdr = (const uint8_t *)req->in.vector[i+0].iov_base;
  57         if (req->in.vector[i+1].iov_len != (expected_body_size & 0xFFFFFFFE)) {
  58                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  59         }
  60
  61         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  62
  63         body_size = SVAL(inbody, 0x00);
  64         if (body_size != expected_body_size) {
  65                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  66         }
  67
  68         in_smbpid = IVAL(inhdr, SMB2_HDR_PID);
  69
  70         in_length               = IVAL(inbody, 0x04);
  71         in_offset               = BVAL(inbody, 0x08);
  72         in_file_id_persistent   = BVAL(inbody, 0x10);
  73         in_file_id_volatile     = BVAL(inbody, 0x18);
  74         in_minimum_count        = IVAL(inbody, 0x20);
  75         in_remaining_bytes      = IVAL(inbody, 0x28);
  76
  77         /* check the max read size */
  78         if (in_length > lp_smb2_max_read()) {
  79                 DEBUG(0,("here:%s: 0x%08X: 0x%08X\n",
  80                         __location__, in_length, lp_smb2_max_read()));
  81                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  82         }
  83
  84         if (req->compat_chain_fsp) {
  85                 /* skip check */
  86         } else if (in_file_id_persistent != in_file_id_volatile) {
  87                 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
  88         }
  89
  90         subreq = smbd_smb2_read_send(req,
  91                                      req->sconn->smb2.event_ctx,
  92                                      req,
  93                                      in_smbpid,
  94                                      in_file_id_volatile,
  95                                      in_length,
  96                                      in_offset,
  97                                      in_minimum_count,
  98                                      in_remaining_bytes);
  99         if (subreq == NULL) {
 100                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 101         }
 102         tevent_req_set_callback(subreq, smbd_smb2_request_read_done, req);
 103
 104         return smbd_smb2_request_pending_queue(req, subreq);
 105 }
 106
 107 static void smbd_smb2_request_read_done(struct tevent_req *subreq)
 108 {
 109         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 110                                         struct smbd_smb2_request);
 111         int i = req->current_idx;
 112         uint8_t *outhdr;
 113         DATA_BLOB outbody;
 114         DATA_BLOB outdyn;
 115         uint8_t out_data_offset;
 116         DATA_BLOB out_data_buffer = data_blob_null;
 117         uint32_t out_data_remaining = 0;
 118         NTSTATUS status;
 119         NTSTATUS error; /* transport error */
 120
 121         status = smbd_smb2_read_recv(subreq,
 122                                      req,
 123                                      &out_data_buffer,
 124                                      &out_data_remaining);
 125         TALLOC_FREE(subreq);
 126         if (!NT_STATUS_IS_OK(status)) {
 127                 error = smbd_smb2_request_error(req, status);
 128                 if (!NT_STATUS_IS_OK(error)) {
 129                         smbd_server_connection_terminate(req->sconn,
 130                                                          nt_errstr(error));
 131                         return;
 132                 }
 133                 return;
 134         }
 135
 136         out_data_offset = SMB2_HDR_BODY + 0x10;
 137
 138         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 139
 140         outbody = data_blob_talloc(req->out.vector, NULL, 0x10);
 141         if (outbody.data == NULL) {
 142                 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 143                 if (!NT_STATUS_IS_OK(error)) {
 144                         smbd_server_connection_terminate(req->sconn,
 145                                                          nt_errstr(error));
 146                         return;
 147                 }
 148                 return;
 149         }
 150
 151         SSVAL(outbody.data, 0x00, 0x10 + 1);    /* struct size */
 152         SCVAL(outbody.data, 0x02,
 153               out_data_offset);                 /* data offset */
 154         SCVAL(outbody.data, 0x03, 0);           /* reserved */
 155         SIVAL(outbody.data, 0x04,
 156               out_data_buffer.length);          /* data length */
 157         SIVAL(outbody.data, 0x08,
 158               out_data_remaining);              /* data remaining */
 159         SIVAL(outbody.data, 0x0C, 0);           /* reserved */
 160
 161         outdyn = out_data_buffer;
 162
 163         error = smbd_smb2_request_done(req, outbody, &outdyn);
 164         if (!NT_STATUS_IS_OK(error)) {
 165                 smbd_server_connection_terminate(req->sconn,
 166                                                  nt_errstr(error));
 167                 return;
 168         }
 169 }
 170
 171 struct smbd_smb2_read_state {
 172         struct smbd_smb2_request *smb2req;
 173         DATA_BLOB out_data;
 174         uint32_t out_remaining;
 175 };
 176
 177 static void smbd_smb2_read_pipe_done(struct tevent_req *subreq);
 178
 179 static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx,
 180                                               struct tevent_context *ev,
 181                                               struct smbd_smb2_request *smb2req,
 182                                               uint32_t in_smbpid,
 183                                               uint64_t in_file_id_volatile,
 184                                               uint32_t in_length,
 185                                               uint64_t in_offset,
 186                                               uint32_t in_minimum,
 187                                               uint32_t in_remaining)
 188 {
 189         struct tevent_req *req;
 190         struct smbd_smb2_read_state *state;
 191         struct smb_request *smbreq;
 192         connection_struct *conn = smb2req->tcon->compat_conn;
 193         files_struct *fsp;
 194         ssize_t nread = -1;
 195         struct lock_struct lock;
 196
 197         req = tevent_req_create(mem_ctx, &state,
 198                                 struct smbd_smb2_read_state);
 199         if (req == NULL) {
 200                 return NULL;
 201         }
 202         state->smb2req = smb2req;
 203         state->out_data = data_blob_null;
 204         state->out_remaining = 0;
 205
 206         DEBUG(10,("smbd_smb2_read: 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         fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile);
 215         if (fsp == NULL) {
 216                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 217                 return tevent_req_post(req, ev);
 218         }
 219         if (conn != fsp->conn) {
 220                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 221                 return tevent_req_post(req, ev);
 222         }
 223         if (smb2req->session->vuid != fsp->vuid) {
 224                 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 225                 return tevent_req_post(req, ev);
 226         }
 227         if (fsp->is_directory) {
 228                 tevent_req_nterror(req, NT_STATUS_INVALID_DEVICE_REQUEST);
 229                 return tevent_req_post(req, ev);
 230         }
 231
 232         state->out_data = data_blob_talloc(state, NULL, in_length);
 233         if (in_length > 0 && tevent_req_nomem(state->out_data.data, req)) {
 234                 return tevent_req_post(req, ev);
 235         }
 236
 237         if (IS_IPC(smbreq->conn)) {
 238                 struct tevent_req *subreq;
 239
 240                 if (!fsp_is_np(fsp)) {
 241                         tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
 242                         return tevent_req_post(req, ev);
 243                 }
 244
 245                 subreq = np_read_send(state, smbd_event_context(),
 246                                       fsp->fake_file_handle,
 247                                       state->out_data.data,
 248                                       state->out_data.length);
 249                 if (tevent_req_nomem(subreq, req)) {
 250                         return tevent_req_post(req, ev);
 251                 }
 252                 tevent_req_set_callback(subreq,
 253                                         smbd_smb2_read_pipe_done,
 254                                         req);
 255                 return req;
 256         }
 257
 258         if (!CHECK_READ(fsp, smbreq)) {
 259                 tevent_req_nterror(req, NT_STATUS_ACCESS_DENIED);
 260                 return tevent_req_post(req, ev);
 261         }
 262
 263         init_strict_lock_struct(fsp,
 264                                 in_file_id_volatile,
 265                                 in_offset,
 266                                 in_length,
 267                                 READ_LOCK,
 268                                 &lock);
 269
 270         if (!SMB_VFS_STRICT_LOCK(conn, fsp, &lock)) {
 271                 tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
 272                 return tevent_req_post(req, ev);
 273         }
 274
 275         nread = read_file(fsp,
 276                           (char *)state->out_data.data,
 277                           in_offset,
 278                           in_length);
 279
 280         SMB_VFS_STRICT_UNLOCK(conn, fsp, &lock);
 281
 282         DEBUG(10,("smbd_smb2_read: file %s handle [0x%016llX] offset=%llu "
 283                 "len=%llu returned %lld\n",
 284                 fsp_str_dbg(fsp),
 285                 (unsigned long long)in_file_id_volatile,
 286                 (unsigned long long)in_offset,
 287                 (unsigned long long)in_length,
 288                 (long long)nread));
 289
 290         if (nread < 0) {
 291                 DEBUG(5,("smbd_smb2_read: read_file[%s] nread[%lld]\n",
 292                          fsp_str_dbg(fsp), (long long)nread));
 293                 tevent_req_nterror(req, NT_STATUS_ACCESS_DENIED);
 294                 return tevent_req_post(req, ev);
 295         }
 296         if (nread == 0 && in_length != 0) {
 297                 DEBUG(5,("smbd_smb2_read: read_file[%s] end of file\n",
 298                          fsp_str_dbg(fsp)));
 299                 tevent_req_nterror(req, NT_STATUS_END_OF_FILE);
 300                 return tevent_req_post(req, ev);
 301         }
 302
 303         if (nread < in_minimum) {
 304                 DEBUG(5,("smbd_smb2_read: read_file[%s] read less %d than "
 305                         "minimum requested %u. Returning end of file\n",
 306                          fsp_str_dbg(fsp),
 307                         (int)nread,
 308                         (unsigned int)in_minimum));
 309                 tevent_req_nterror(req, NT_STATUS_END_OF_FILE);
 310                 return tevent_req_post(req, ev);
 311         }
 312
 313         DEBUG(3,("smbd_smb2_read: fnum=[%d/%s] length=%lu offset=%lu read=%lu\n",
 314                 fsp->fnum, fsp_str_dbg(fsp),
 315                 (unsigned long)in_length,
 316                 (unsigned long)in_offset,
 317                 (unsigned long)nread));
 318
 319         state->out_data.length = nread;
 320         state->out_remaining = 0;
 321         tevent_req_done(req);
 322         return tevent_req_post(req, ev);
 323 }
 324
 325 static void smbd_smb2_read_pipe_done(struct tevent_req *subreq)
 326 {
 327         struct tevent_req *req = tevent_req_callback_data(subreq,
 328                                  struct tevent_req);
 329         struct smbd_smb2_read_state *state = tevent_req_data(req,
 330                                              struct smbd_smb2_read_state);
 331         NTSTATUS status;
 332         ssize_t nread = -1;
 333         bool is_data_outstanding;
 334
 335         status = np_read_recv(subreq, &nread, &is_data_outstanding);
 336         TALLOC_FREE(subreq);
 337         if (!NT_STATUS_IS_OK(status)) {
 338                 tevent_req_nterror(req, status);
 339                 return;
 340         }
 341
 342         if (nread == 0 && state->out_data.length != 0) {
 343                 tevent_req_nterror(req, NT_STATUS_END_OF_FILE);
 344                 return;
 345         }
 346
 347         state->out_data.length = nread;
 348         state->out_remaining = 0;
 349
 350         tevent_req_done(req);
 351 }
 352
 353 static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req,
 354                                     TALLOC_CTX *mem_ctx,
 355                                     DATA_BLOB *out_data,
 356                                     uint32_t *out_remaining)
 357 {
 358         NTSTATUS status;
 359         struct smbd_smb2_read_state *state = tevent_req_data(req,
 360                                              struct smbd_smb2_read_state);
 361
 362         if (tevent_req_is_nterror(req, &status)) {
 363                 tevent_req_received(req);
 364                 return status;
 365         }
 366
 367         *out_data = state->out_data;
 368         talloc_steal(mem_ctx, out_data->data);
 369         *out_remaining = state->out_remaining;
 370
 371         tevent_req_received(req);
 372         return NT_STATUS_OK;
 373 }