source3/smbd/smb2_server.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 "../source4/libcli/smb2/smb2_constants.h"
  24 #include "../lib/tsocket/tsocket.h"
  25
  26 bool smbd_is_smb2_header(const uint8_t *inbuf, size_t size)
  27 {
  28         if (size < (4 + SMB2_HDR_BODY)) {
  29                 return false;
  30         }
  31
  32         if (IVAL(inbuf, 4) != SMB2_MAGIC) {
  33                 return false;
  34         }
  35
  36         return true;
  37 }
  38
  39 static NTSTATUS smbd_initialize_smb2(struct smbd_server_connection *conn)
  40 {
  41         NTSTATUS status;
  42         int ret;
  43
  44         TALLOC_FREE(conn->fde);
  45
  46         conn->smb2.event_ctx = smbd_event_context();
  47
  48         conn->smb2.recv_queue = tevent_queue_create(conn, "smb2 recv queue");
  49         if (conn->smb2.recv_queue == NULL) {
  50                 return NT_STATUS_NO_MEMORY;
  51         }
  52
  53         conn->smb2.send_queue = tevent_queue_create(conn, "smb2 send queue");
  54         if (conn->smb2.send_queue == NULL) {
  55                 return NT_STATUS_NO_MEMORY;
  56         }
  57
  58         ret = tstream_bsd_existing_socket(conn, smbd_server_fd(),
  59                                           &conn->smb2.stream);
  60         if (ret == -1) {
  61                 status = map_nt_error_from_unix(errno);
  62                 return status;
  63         }
  64
  65         /* Ensure child is set to non-blocking mode */
  66         set_blocking(smbd_server_fd(),false);
  67         return NT_STATUS_OK;
  68 }
  69
  70 #define smb2_len(buf) (PVAL(buf,3)|(PVAL(buf,2)<<8)|(PVAL(buf,1)<<16))
  71 #define _smb2_setlen(_buf,len) do { \
  72         uint8_t *buf = (uint8_t *)_buf; \
  73         buf[0] = 0; \
  74         buf[1] = ((len)&0xFF0000)>>16; \
  75         buf[2] = ((len)&0xFF00)>>8; \
  76         buf[3] = (len)&0xFF; \
  77 } while (0)
  78
  79 static void smb2_setup_nbt_length(struct iovec *vector, int count)
  80 {
  81         size_t len = 0;
  82         int i;
  83
  84         for (i=1; i < count; i++) {
  85                 len += vector[i].iov_len;
  86         }
  87
  88         _smb2_setlen(vector[0].iov_base, len);
  89 }
  90
  91 static NTSTATUS smbd_smb2_request_create(struct smbd_server_connection *conn,
  92                                          const uint8_t *inbuf, size_t size,
  93                                          struct smbd_smb2_request **_req)
  94 {
  95         TALLOC_CTX *mem_pool;
  96         struct smbd_smb2_request *req;
  97         uint32_t protocol_version;
  98         const uint8_t *inhdr = NULL;
  99         off_t ofs = 0;
 100         uint16_t cmd;
 101         uint32_t next_command_ofs;
 102
 103         if (size < (4 + SMB2_HDR_BODY + 2)) {
 104                 DEBUG(0,("Invalid SMB2 packet length count %ld\n", (long)size));
 105                 return NT_STATUS_INVALID_PARAMETER;
 106         }
 107
 108         inhdr = inbuf + 4;
 109
 110         protocol_version = IVAL(inhdr, SMB2_HDR_PROTOCOL_ID);
 111         if (protocol_version != SMB2_MAGIC) {
 112                 DEBUG(0,("Invalid SMB packet: protocol prefix: 0x%08X\n",
 113                          protocol_version));
 114                 return NT_STATUS_INVALID_PARAMETER;
 115         }
 116
 117         cmd = SVAL(inhdr, SMB2_HDR_OPCODE);
 118         if (cmd != SMB2_OP_NEGPROT) {
 119                 DEBUG(0,("Invalid SMB packet: first request: 0x%04X\n",
 120                          cmd));
 121                 return NT_STATUS_INVALID_PARAMETER;
 122         }
 123
 124         next_command_ofs = IVAL(inhdr, SMB2_HDR_NEXT_COMMAND);
 125         if (next_command_ofs != 0) {
 126                 DEBUG(0,("Invalid SMB packet: next_command: 0x%08X\n",
 127                          next_command_ofs));
 128                 return NT_STATUS_INVALID_PARAMETER;
 129         }
 130
 131         mem_pool = talloc_pool(conn, 8192);
 132         if (mem_pool == NULL) {
 133                 return NT_STATUS_NO_MEMORY;
 134         }
 135
 136         req = talloc_zero(mem_pool, struct smbd_smb2_request);
 137         if (req == NULL) {
 138                 talloc_free(mem_pool);
 139                 return NT_STATUS_NO_MEMORY;
 140         }
 141         req->mem_pool   = mem_pool;
 142         req->conn       = conn;
 143
 144         talloc_steal(req, inbuf);
 145
 146         req->in.vector = talloc_array(req, struct iovec, 4);
 147         if (req->in.vector == NULL) {
 148                 talloc_free(mem_pool);
 149                 return NT_STATUS_NO_MEMORY;
 150         }
 151         req->in.vector_count = 4;
 152
 153         memcpy(req->in.nbt_hdr, inbuf, 4);
 154
 155         ofs = 0;
 156         req->in.vector[0].iov_base      = (void *)req->in.nbt_hdr;
 157         req->in.vector[0].iov_len       = 4;
 158         ofs += req->in.vector[0].iov_len;
 159
 160         req->in.vector[1].iov_base      = (void *)(inbuf + ofs);
 161         req->in.vector[1].iov_len       = SMB2_HDR_BODY;
 162         ofs += req->in.vector[1].iov_len;
 163
 164         req->in.vector[2].iov_base      = (void *)(inbuf + ofs);
 165         req->in.vector[2].iov_len       = SVAL(inbuf, ofs) & 0xFFFE;
 166         ofs += req->in.vector[2].iov_len;
 167
 168         if (ofs > size) {
 169                 return NT_STATUS_INVALID_PARAMETER;
 170         }
 171
 172         req->in.vector[3].iov_base      = (void *)(inbuf + ofs);
 173         req->in.vector[3].iov_len       = size - ofs;
 174         ofs += req->in.vector[3].iov_len;
 175
 176         req->current_idx = 1;
 177
 178         *_req = req;
 179         return NT_STATUS_OK;
 180 }
 181
 182 static NTSTATUS smbd_smb2_request_setup_out(struct smbd_smb2_request *req)
 183 {
 184         struct iovec *vector;
 185         int count;
 186         int idx;
 187
 188         count = req->in.vector_count;
 189         vector = talloc_array(req, struct iovec, count);
 190         if (vector == NULL) {
 191                 return NT_STATUS_NO_MEMORY;
 192         }
 193
 194         vector[0].iov_base      = req->out.nbt_hdr;
 195         vector[0].iov_len       = 4;
 196         SIVAL(req->out.nbt_hdr, 0, 0);
 197
 198         for (idx=1; idx < count; idx += 3) {
 199                 const uint8_t *inhdr = NULL;
 200                 uint8_t *outhdr = NULL;
 201                 uint8_t *outbody = NULL;
 202                 uint8_t *outdyn = NULL;
 203                 size_t outdyn_size = 1;
 204                 uint32_t next_command_ofs = 0;
 205                 struct iovec *current = &vector[idx];
 206
 207                 if ((idx + 3) < count) {
 208                         /* we have a next command */
 209                         next_command_ofs = SMB2_HDR_BODY + 8 + 8;
 210                         outdyn_size = 8;
 211                 }
 212
 213                 inhdr = (const uint8_t *)req->in.vector[idx].iov_base;
 214
 215                 outhdr = talloc_array(vector, uint8_t,
 216                                       SMB2_HDR_BODY + 8 + outdyn_size);
 217                 if (outhdr == NULL) {
 218                         return NT_STATUS_NO_MEMORY;
 219                 }
 220
 221                 outbody = outhdr + SMB2_HDR_BODY;
 222                 outdyn = outbody + 8;
 223
 224                 current[0].iov_base     = (void *)outhdr;
 225                 current[0].iov_len      = SMB2_HDR_BODY;
 226
 227                 current[1].iov_base     = (void *)outbody;
 228                 current[1].iov_len      = 8;
 229
 230                 current[2].iov_base     = (void *)outdyn;
 231                 current[2].iov_len      = outdyn_size;
 232
 233                 /* setup the SMB2 header */
 234                 SIVAL(outhdr, SMB2_HDR_PROTOCOL_ID,     SMB2_MAGIC);
 235                 SSVAL(outhdr, SMB2_HDR_LENGTH,          SMB2_HDR_BODY);
 236                 SSVAL(outhdr, SMB2_HDR_EPOCH,           0);
 237                 SIVAL(outhdr, SMB2_HDR_STATUS,
 238                       NT_STATUS_V(NT_STATUS_INTERNAL_ERROR));
 239                 SSVAL(outhdr, SMB2_HDR_OPCODE,
 240                       SVAL(inhdr, SMB2_HDR_OPCODE));
 241                 SSVAL(outhdr, SMB2_HDR_CREDIT,          0);
 242                 SIVAL(outhdr, SMB2_HDR_FLAGS,           SMB2_HDR_FLAG_REDIRECT);
 243                 SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND,    next_command_ofs);
 244                 SIVAL(outhdr, SMB2_HDR_MESSAGE_ID,
 245                       IVAL(inhdr, SMB2_HDR_MESSAGE_ID));
 246                 SIVAL(outhdr, SMB2_HDR_PID,
 247                       IVAL(inhdr, SMB2_HDR_PID));
 248                 SIVAL(outhdr, SMB2_HDR_TID,
 249                       IVAL(inhdr, SMB2_HDR_TID));
 250                 SIVAL(outhdr, SMB2_HDR_SESSION_ID,
 251                       IVAL(inhdr, SMB2_HDR_SESSION_ID));
 252                 memset(outhdr + SMB2_HDR_SIGNATURE, 0, 16);
 253
 254                 /* setup error body header */
 255                 SSVAL(outbody, 0x00, 9);
 256                 SSVAL(outbody, 0x02, 0);
 257                 SIVAL(outbody, 0x04, 0);
 258
 259                 /* setup the dynamic part */
 260                 SCVAL(outdyn, 0x00, 0);
 261         }
 262
 263         req->out.vector = vector;
 264         req->out.vector_count = count;
 265
 266         /* setup the length of the NBT packet */
 267         smb2_setup_nbt_length(req->out.vector, req->out.vector_count);
 268
 269         return NT_STATUS_OK;
 270 }
 271
 272 static void smbd_server_connection_terminate(struct smbd_server_connection *conn,
 273                                              const char *reason)
 274 {
 275         DEBUG(10,("smbd_server_connection_terminate: reason[%s]\n", reason));
 276         exit_server_cleanly(reason);
 277 }
 278
 279 static NTSTATUS smbd_smb2_request_dispatch(struct smbd_smb2_request *req)
 280 {
 281         const uint8_t *inhdr;
 282         int i = req->current_idx;
 283         uint16_t opcode;
 284
 285         inhdr = (const uint8_t *)req->in.vector[i].iov_base;
 286
 287         /* TODO: verify more things */
 288
 289         opcode = IVAL(inhdr, SMB2_HDR_OPCODE);
 290         DEBUG(10,("smbd_smb2_request_dispatch: opcode[%u]\n", opcode));
 291         switch (opcode) {
 292         case SMB2_OP_NEGPROT:
 293                 return smbd_smb2_request_process_negprot(req);
 294
 295         case SMB2_OP_SESSSETUP:
 296         case SMB2_OP_LOGOFF:
 297         case SMB2_OP_TCON:
 298         case SMB2_OP_TDIS:
 299         case SMB2_OP_CREATE:
 300         case SMB2_OP_CLOSE:
 301         case SMB2_OP_FLUSH:
 302         case SMB2_OP_READ:
 303         case SMB2_OP_WRITE:
 304         case SMB2_OP_LOCK:
 305         case SMB2_OP_IOCTL:
 306         case SMB2_OP_CANCEL:
 307         case SMB2_OP_KEEPALIVE:
 308         case SMB2_OP_FIND:
 309         case SMB2_OP_NOTIFY:
 310         case SMB2_OP_GETINFO:
 311         case SMB2_OP_SETINFO:
 312         case SMB2_OP_BREAK:
 313                 return smbd_smb2_request_error(req, NT_STATUS_NOT_IMPLEMENTED);
 314         }
 315
 316         return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 317 }
 318
 319 static void smbd_smb2_request_dispatch_compound(struct tevent_req *subreq);
 320 static void smbd_smb2_request_writev_done(struct tevent_req *subreq);
 321
 322 static NTSTATUS smbd_smb2_request_reply(struct smbd_smb2_request *req)
 323 {
 324         struct tevent_req *subreq;
 325
 326         /* TODO: sign the response here */
 327
 328         smb2_setup_nbt_length(req->out.vector, req->out.vector_count);
 329
 330         req->current_idx += 3;
 331
 332         if (req->current_idx > req->in.vector_count) {
 333                 struct timeval zero = timeval_zero();
 334                 subreq = tevent_wakeup_send(req,
 335                                             req->conn->smb2.event_ctx,
 336                                             zero);
 337                 if (subreq == NULL) {
 338                         return NT_STATUS_NO_MEMORY;
 339                 }
 340                 tevent_req_set_callback(subreq,
 341                                         smbd_smb2_request_dispatch_compound,
 342                                         req);
 343
 344                 return NT_STATUS_OK;
 345         }
 346
 347         subreq = tstream_writev_queue_send(req,
 348                                            req->conn->smb2.event_ctx,
 349                                            req->conn->smb2.stream,
 350                                            req->conn->smb2.send_queue,
 351                                            req->out.vector,
 352                                            req->out.vector_count);
 353         if (subreq == NULL) {
 354                 return NT_STATUS_NO_MEMORY;
 355         }
 356         tevent_req_set_callback(subreq, smbd_smb2_request_writev_done, req);
 357
 358         return NT_STATUS_OK;
 359 }
 360
 361 NTSTATUS smbd_smb2_request_error_ex(struct smbd_smb2_request *req,
 362                                     NTSTATUS status,
 363                                     DATA_BLOB *info)
 364 {
 365         uint8_t *outhdr;
 366         uint8_t *outbody;
 367         int i = req->current_idx;
 368
 369         DEBUG(10,("smbd_smb2_request_error_ex: idx[%d] status[%s]%s\n",
 370                   i, nt_errstr(status), info ? " +info" : ""));
 371
 372         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 373
 374         SIVAL(outhdr, SMB2_HDR_STATUS, NT_STATUS_V(status));
 375
 376         outbody = outhdr + SMB2_HDR_BODY;
 377
 378         req->out.vector[i+1].iov_base = (void *)outbody;
 379         req->out.vector[i+1].iov_len = 8;
 380
 381         if (info) {
 382                 SIVAL(outbody, 0x04, info->length);
 383                 req->out.vector[i+2].iov_base   = (void *)info->data;
 384                 req->out.vector[i+2].iov_len    = info->length;
 385         } else {
 386                 req->out.vector[i+2].iov_base = (void *)(outbody + 8);
 387                 req->out.vector[i+2].iov_len = 1;
 388         }
 389
 390         /* the error packet is the last response in the chain */
 391         SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND, 0);
 392         req->out.vector_count = req->current_idx + 3;
 393
 394         return smbd_smb2_request_reply(req);
 395 }
 396
 397 NTSTATUS smbd_smb2_request_error(struct smbd_smb2_request *req,
 398                                  NTSTATUS status)
 399 {
 400         return smbd_smb2_request_error_ex(req, status, NULL);
 401 }
 402
 403 NTSTATUS smbd_smb2_request_done(struct smbd_smb2_request *req,
 404                                 DATA_BLOB body, DATA_BLOB *dyn)
 405 {
 406         uint8_t *outhdr;
 407         uint8_t *outdyn;
 408         int i = req->current_idx;
 409         uint32_t next_command_ofs;
 410
 411         DEBUG(10,("smbd_smb2_request_done: idx[%d] body[%u] dyn[%s:%u]\n",
 412                   i, (unsigned int)body.length,
 413                   dyn ? "yes": "no",
 414                   (unsigned int)(dyn ? dyn->length : 0)));
 415
 416         if (body.length < 2) {
 417                 return smbd_smb2_request_error(req, NT_STATUS_INTERNAL_ERROR);
 418         }
 419
 420         if ((body.length % 2) != 0) {
 421                 return smbd_smb2_request_error(req, NT_STATUS_INTERNAL_ERROR);
 422         }
 423
 424         outhdr = (uint8_t *)req->out.vector[i].iov_base;
 425         /* the fallback dynamic buffer */
 426         outdyn = outhdr + SMB2_HDR_BODY + 8;
 427
 428         next_command_ofs = SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND, 0);
 429         SIVAL(outhdr, SMB2_HDR_STATUS, NT_STATUS_V(NT_STATUS_OK));
 430
 431         req->out.vector[i+1].iov_base = (void *)body.data;
 432         req->out.vector[i+1].iov_len = body.length;
 433
 434         if (dyn) {
 435                 if (dyn->length > 0) {
 436                         req->out.vector[i+2].iov_base   = (void *)dyn->data;
 437                         req->out.vector[i+2].iov_len    = dyn->length;
 438                 } else {
 439                         req->out.vector[i+2].iov_base   = (void *)outdyn;
 440                         req->out.vector[i+2].iov_len    = 1;
 441                 }
 442         } else {
 443                 req->out.vector[i+2].iov_base = NULL;
 444                 req->out.vector[i+2].iov_len = 0;
 445         }
 446
 447         /* see if we need to recalculate the offset to the next response */
 448         if (next_command_ofs > 0) {
 449                 next_command_ofs  = SMB2_HDR_BODY;
 450                 next_command_ofs += req->out.vector[i+1].iov_len;
 451                 next_command_ofs += req->out.vector[i+2].iov_len;
 452         }
 453
 454         /* TODO: we need to add padding ... */
 455         if ((next_command_ofs % 8) != 0) {
 456                 return smbd_smb2_request_error(req, NT_STATUS_INTERNAL_ERROR);
 457         }
 458
 459         /* the error packet is the last response in the chain */
 460         SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND, next_command_ofs);
 461
 462         return smbd_smb2_request_reply(req);
 463 }
 464
 465 static void smbd_smb2_request_dispatch_compound(struct tevent_req *subreq)
 466 {
 467         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 468                                         struct smbd_smb2_request);
 469         struct smbd_server_connection *conn = req->conn;
 470         NTSTATUS status;
 471
 472         tevent_wakeup_recv(subreq);
 473         TALLOC_FREE(subreq);
 474
 475         DEBUG(10,("smbd_smb2_request_dispatch_compound: idx[%d] of %d vectors\n",
 476                   req->current_idx, req->in.vector_count));
 477
 478         status = smbd_smb2_request_dispatch(req);
 479         if (!NT_STATUS_IS_OK(status)) {
 480                 smbd_server_connection_terminate(conn, nt_errstr(status));
 481                 return;
 482         }
 483 }
 484
 485 static void smbd_smb2_request_writev_done(struct tevent_req *subreq)
 486 {
 487         struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
 488                                         struct smbd_smb2_request);
 489         struct smbd_server_connection *conn = req->conn;
 490         int ret;
 491         int sys_errno;
 492         TALLOC_CTX *mem_pool;
 493
 494         ret = tstream_writev_queue_recv(subreq, &sys_errno);
 495         TALLOC_FREE(subreq);
 496         if (ret == -1) {
 497                 NTSTATUS status = map_nt_error_from_unix(sys_errno);
 498                 smbd_server_connection_terminate(conn, nt_errstr(status));
 499                 return;
 500         }
 501
 502         mem_pool = req->mem_pool;
 503         req = NULL;
 504         talloc_free(mem_pool);
 505 }
 506
 507 struct smbd_smb2_request_read_state {
 508         size_t missing;
 509         bool asked_for_header;
 510         struct smbd_smb2_request *smb2_req;
 511 };
 512
 513 static int smbd_smb2_request_next_vector(struct tstream_context *stream,
 514                                          void *private_data,
 515                                          TALLOC_CTX *mem_ctx,
 516                                          struct iovec **_vector,
 517                                          size_t *_count);
 518 static void smbd_smb2_request_read_done(struct tevent_req *subreq);
 519
 520 static struct tevent_req *smbd_smb2_request_read_send(TALLOC_CTX *mem_ctx,
 521                                         struct tevent_context *ev,
 522                                         struct smbd_server_connection *conn)
 523 {
 524         struct tevent_req *req;
 525         struct smbd_smb2_request_read_state *state;
 526         struct tevent_req *subreq;
 527         TALLOC_CTX *mem_pool;
 528
 529         req = tevent_req_create(mem_ctx, &state,
 530                                 struct smbd_smb2_request_read_state);
 531         if (req == NULL) {
 532                 return NULL;
 533         }
 534         state->missing = 0;
 535         state->asked_for_header = false;
 536
 537         mem_pool = talloc_pool(state, 8192);
 538         if (tevent_req_nomem(mem_pool, req)) {
 539                 return tevent_req_post(req, ev);
 540         }
 541
 542         state->smb2_req = talloc_zero(mem_pool, struct smbd_smb2_request);
 543         if (tevent_req_nomem(state->smb2_req, req)) {
 544                 return tevent_req_post(req, ev);
 545         }
 546
 547         state->smb2_req->mem_pool       = mem_pool;
 548         state->smb2_req->conn           = conn;
 549
 550         subreq = tstream_readv_pdu_queue_send(state, ev, conn->smb2.stream,
 551                                               conn->smb2.recv_queue,
 552                                               smbd_smb2_request_next_vector,
 553                                               state);
 554         if (tevent_req_nomem(subreq, req)) {
 555                 return tevent_req_post(req, ev);
 556         }
 557         tevent_req_set_callback(subreq, smbd_smb2_request_read_done, req);
 558
 559         return req;
 560 }
 561
 562 static int smbd_smb2_request_next_vector(struct tstream_context *stream,
 563                                          void *private_data,
 564                                          TALLOC_CTX *mem_ctx,
 565                                          struct iovec **_vector,
 566                                          size_t *_count)
 567 {
 568         struct smbd_smb2_request_read_state *state =
 569                 talloc_get_type_abort(private_data,
 570                 struct smbd_smb2_request_read_state);
 571         struct smbd_smb2_request *req = state->smb2_req;
 572         struct iovec *vector;
 573         int idx = req->in.vector_count;
 574         size_t len = 0;
 575         uint8_t *buf = NULL;
 576
 577         if (req->in.vector_count == 0) {
 578                 /*
 579                  * first we need to get the NBT header
 580                  */
 581                 req->in.vector = talloc_array(req, struct iovec,
 582                                               req->in.vector_count + 1);
 583                 if (req->in.vector == NULL) {
 584                         return -1;
 585                 }
 586                 req->in.vector_count += 1;
 587
 588                 req->in.vector[idx].iov_base    = (void *)req->in.nbt_hdr;
 589                 req->in.vector[idx].iov_len     = 4;
 590
 591                 vector = talloc_array(mem_ctx, struct iovec, 1);
 592                 if (vector == NULL) {
 593                         return -1;
 594                 }
 595
 596                 vector[0] = req->in.vector[idx];
 597
 598                 *_vector = vector;
 599                 *_count = 1;
 600                 return 0;
 601         }
 602
 603         if (req->in.vector_count == 1) {
 604                 /*
 605                  * Now we analyze the NBT header
 606                  */
 607                 state->missing = smb2_len(req->in.vector[0].iov_base);
 608
 609                 if (state->missing == 0) {
 610                         /* if there're no remaining bytes, we're done */
 611                         *_vector = NULL;
 612                         *_count = 0;
 613                         return 0;
 614                 }
 615
 616                 req->in.vector = talloc_realloc(req, req->in.vector,
 617                                                 struct iovec,
 618                                                 req->in.vector_count + 1);
 619                 if (req->in.vector == NULL) {
 620                         return -1;
 621                 }
 622                 req->in.vector_count += 1;
 623
 624                 if (CVAL(req->in.vector[0].iov_base, 0) != 0) {
 625                         /*
 626                          * it's a special NBT message,
 627                          * so get all remaining bytes
 628                          */
 629                         len = state->missing;
 630                 } else if (state->missing < (SMB2_HDR_BODY + 2)) {
 631                         /*
 632                          * it's an invalid message, just read what we can get
 633                          * and let the caller handle the error
 634                          */
 635                         len = state->missing;
 636                 } else {
 637                         /*
 638                          * We assume it's a SMB2 request,
 639                          * and we first get the header and the
 640                          * first 2 bytes (the struct size) of the body
 641                          */
 642                         len = SMB2_HDR_BODY + 2;
 643
 644                         state->asked_for_header = true;
 645                 }
 646
 647                 state->missing -= len;
 648
 649                 buf = talloc_array(req->in.vector, uint8_t, len);
 650                 if (buf == NULL) {
 651                         return -1;
 652                 }
 653
 654                 req->in.vector[idx].iov_base    = (void *)buf;
 655                 req->in.vector[idx].iov_len     = len;
 656
 657                 vector = talloc_array(mem_ctx, struct iovec, 1);
 658                 if (vector == NULL) {
 659                         return -1;
 660                 }
 661
 662                 vector[0] = req->in.vector[idx];
 663
 664                 *_vector = vector;
 665                 *_count = 1;
 666                 return 0;
 667         }
 668
 669         if (state->missing == 0) {
 670                 /* if there're no remaining bytes, we're done */
 671                 *_vector = NULL;
 672                 *_count = 0;
 673                 return 0;
 674         }
 675
 676         if (state->asked_for_header) {
 677                 const uint8_t *hdr;
 678                 size_t full_size;
 679                 size_t next_command_ofs;
 680                 size_t body_size;
 681                 uint8_t *body;
 682                 size_t dyn_size;
 683                 uint8_t *dyn;
 684                 bool invalid = false;
 685
 686                 state->asked_for_header = false;
 687
 688                 /*
 689                  * We got the SMB2 header and the first 2 bytes
 690                  * of the body. We fix the size to just the header
 691                  * and manually copy the 2 first bytes to the body section
 692                  */
 693                 req->in.vector[idx-1].iov_len = SMB2_HDR_BODY;
 694                 hdr = (const uint8_t *)req->in.vector[idx-1].iov_base;
 695
 696                 /* allocate vectors for body and dynamic areas */
 697                 req->in.vector = talloc_realloc(req, req->in.vector,
 698                                                 struct iovec,
 699                                                 req->in.vector_count + 2);
 700                 if (req->in.vector == NULL) {
 701                         return -1;
 702                 }
 703                 req->in.vector_count += 2;
 704
 705                 full_size = state->missing + SMB2_HDR_BODY + 2;
 706                 next_command_ofs = IVAL(hdr, SMB2_HDR_NEXT_COMMAND);
 707                 body_size = SVAL(hdr, SMB2_HDR_BODY);
 708
 709                 if (next_command_ofs != 0) {
 710                         if (next_command_ofs < (SMB2_HDR_BODY + 2)) {
 711                                 /*
 712                                  * this is invalid, just return a zero
 713                                  * body and let the caller deal with the error
 714                                  */
 715                                 invalid = true;
 716                         } else if (next_command_ofs > full_size) {
 717                                 /*
 718                                  * this is invalid, just return a zero
 719                                  * body and let the caller deal with the error
 720                                  */
 721                                 invalid = true;
 722                         } else {
 723                                 full_size = next_command_ofs;
 724                         }
 725                 }
 726
 727                 if (!invalid) {
 728                         if (body_size < 2) {
 729                                 /*
 730                                  * this is invalid, just return a zero
 731                                  * body and let the caller deal with the error
 732                                  */
 733                                 invalid = true;
 734                         } else if (body_size > (full_size - SMB2_HDR_BODY)) {
 735                                 /*
 736                                  * this is invalid, just return a zero
 737                                  * body and let the caller deal with the error
 738                                  */
 739                                 invalid = true;
 740                         }
 741                 }
 742
 743                 if (invalid) {
 744                         /* the caller should check this */
 745                         body_size = 0;
 746                 }
 747
 748                 if ((body_size % 2) != 0) {
 749                         body_size -= 1;
 750                 }
 751
 752                 dyn_size = full_size - (SMB2_HDR_BODY + body_size);
 753
 754                 state->missing -= (body_size - 2) + dyn_size;
 755
 756                 body = talloc_array(req->in.vector, uint8_t, body_size);
 757                 if (body == NULL) {
 758                         return -1;
 759                 }
 760
 761                 dyn = talloc_array(req->in.vector, uint8_t, dyn_size);
 762                 if (dyn == NULL) {
 763                         return -1;
 764                 }
 765
 766                 req->in.vector[idx].iov_base    = (void *)body;
 767                 req->in.vector[idx].iov_len     = body_size;
 768                 req->in.vector[idx+1].iov_base  = (void *)dyn;
 769                 req->in.vector[idx+1].iov_len   = dyn_size;
 770
 771                 vector = talloc_array(mem_ctx, struct iovec, 2);
 772                 if (vector == NULL) {
 773                         return -1;
 774                 }
 775
 776                 /*
 777                  * the first 2 bytes of the body were already fetched
 778                  * together with the header
 779                  */
 780                 memcpy(body, hdr + SMB2_HDR_BODY, 2);
 781                 vector[0].iov_base = body + 2;
 782                 vector[0].iov_len = req->in.vector[idx].iov_len - 2;
 783
 784                 vector[1] = req->in.vector[idx+1];
 785
 786                 *_vector = vector;
 787                 *_count = 2;
 788                 return 0;
 789         }
 790
 791         /*
 792          * when we endup here, we're looking for a new SMB2 request
 793          * next. And we ask for its header and the first 2 bytes of
 794          * the body (like we did for the first SMB2 request).
 795          */
 796
 797         req->in.vector = talloc_realloc(req, req->in.vector,
 798                                         struct iovec,
 799                                         req->in.vector_count + 1);
 800         if (req->in.vector == NULL) {
 801                 return -1;
 802         }
 803         req->in.vector_count += 1;
 804
 805         /*
 806          * We assume it's a SMB2 request,
 807          * and we first get the header and the
 808          * first 2 bytes (the struct size) of the body
 809          */
 810         len = SMB2_HDR_BODY + 2;
 811
 812         if (len > state->missing) {
 813                 /* let the caller handle the error */
 814                 len = state->missing;
 815         }
 816
 817         state->missing -= len;
 818         state->asked_for_header = true;
 819
 820         buf = talloc_array(req->in.vector, uint8_t, len);
 821         if (buf == NULL) {
 822                 return -1;
 823         }
 824
 825         req->in.vector[idx].iov_base    = (void *)buf;
 826         req->in.vector[idx].iov_len     = len;
 827
 828         vector = talloc_array(mem_ctx, struct iovec, 1);
 829         if (vector == NULL) {
 830                 return -1;
 831         }
 832
 833         vector[0] = req->in.vector[idx];
 834
 835         *_vector = vector;
 836         *_count = 1;
 837         return 0;
 838 }
 839
 840 static void smbd_smb2_request_read_done(struct tevent_req *subreq)
 841 {
 842         struct tevent_req *req =
 843                 tevent_req_callback_data(subreq,
 844                 struct tevent_req);
 845         int ret;
 846         int sys_errno;
 847         NTSTATUS status;
 848
 849         ret = tstream_readv_pdu_queue_recv(subreq, &sys_errno);
 850         if (ret == -1) {
 851                 status = map_nt_error_from_unix(sys_errno);
 852                 tevent_req_nterror(req, status);
 853                 return;
 854         }
 855
 856         tevent_req_done(req);
 857 }
 858
 859 static NTSTATUS smbd_smb2_request_read_recv(struct tevent_req *req,
 860                                             TALLOC_CTX *mem_ctx,
 861                                             struct smbd_smb2_request **_smb2_req)
 862 {
 863         struct smbd_smb2_request_read_state *state =
 864                 tevent_req_data(req,
 865                 struct smbd_smb2_request_read_state);
 866         NTSTATUS status;
 867
 868         if (tevent_req_is_nterror(req, &status)) {
 869                 tevent_req_received(req);
 870                 return status;
 871         }
 872
 873         talloc_steal(mem_ctx, state->smb2_req->mem_pool);
 874         *_smb2_req = state->smb2_req;
 875         tevent_req_received(req);
 876         return NT_STATUS_OK;
 877 }
 878
 879 static void smbd_smb2_request_incoming(struct tevent_req *subreq);
 880
 881 void smbd_smb2_first_negprot(struct smbd_server_connection *conn,
 882                              const uint8_t *inbuf, size_t size)
 883 {
 884         NTSTATUS status;
 885         struct smbd_smb2_request *req;
 886         struct tevent_req *subreq;
 887
 888         DEBUG(10,("smbd_smb2_first_negprot: packet length %u\n",
 889                  (unsigned int)size));
 890
 891         status = smbd_initialize_smb2(conn);
 892         if (!NT_STATUS_IS_OK(status)) {
 893                 smbd_server_connection_terminate(conn, nt_errstr(status));
 894                 return;
 895         }
 896
 897         status = smbd_smb2_request_create(conn, inbuf, size, &req);
 898         if (!NT_STATUS_IS_OK(status)) {
 899                 smbd_server_connection_terminate(conn, nt_errstr(status));
 900                 return;
 901         }
 902
 903         status = smbd_smb2_request_setup_out(req);
 904         if (!NT_STATUS_IS_OK(status)) {
 905                 smbd_server_connection_terminate(conn, nt_errstr(status));
 906                 return;
 907         }
 908
 909         status = smbd_smb2_request_dispatch(req);
 910         if (!NT_STATUS_IS_OK(status)) {
 911                 smbd_server_connection_terminate(conn, nt_errstr(status));
 912                 return;
 913         }
 914
 915         /* ask for the next request */
 916         subreq = smbd_smb2_request_read_send(conn,conn->smb2.event_ctx, conn);
 917         if (subreq == NULL) {
 918                 smbd_server_connection_terminate(conn, "no memory for reading");
 919                 return;
 920         }
 921         tevent_req_set_callback(subreq, smbd_smb2_request_incoming, conn);
 922 }
 923
 924 static void smbd_smb2_request_incoming(struct tevent_req *subreq)
 925 {
 926         struct smbd_server_connection *conn = tevent_req_callback_data(subreq,
 927                                               struct smbd_server_connection);
 928         NTSTATUS status;
 929         struct smbd_smb2_request *req;
 930
 931         status = smbd_smb2_request_read_recv(subreq, conn, &req);
 932         TALLOC_FREE(subreq);
 933         if (!NT_STATUS_IS_OK(status)) {
 934                 smbd_server_connection_terminate(conn, nt_errstr(status));
 935                 return;
 936         }
 937
 938         /* TODO: validate the incoming request */
 939         req->current_idx = 1;
 940
 941         DEBUG(10,("smbd_smb2_request_incoming: idx[%d] of %d vectors\n",
 942                  req->current_idx, req->in.vector_count));
 943
 944         status = smbd_smb2_request_setup_out(req);
 945         if (!NT_STATUS_IS_OK(status)) {
 946                 smbd_server_connection_terminate(conn, nt_errstr(status));
 947                 return;
 948         }
 949
 950         status = smbd_smb2_request_dispatch(req);
 951         if (!NT_STATUS_IS_OK(status)) {
 952                 smbd_server_connection_terminate(conn, nt_errstr(status));
 953                 return;
 954         }
 955
 956         /* ask for the next request (this constructs the main loop) */
 957         subreq = smbd_smb2_request_read_send(conn,conn->smb2.event_ctx, conn);
 958         if (subreq == NULL) {
 959                 smbd_server_connection_terminate(conn, "no memory for reading");
 960                 return;
 961         }
 962         tevent_req_set_callback(subreq, smbd_smb2_request_incoming, conn);
 963 }