source3/libsmb/smb_signing.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    SMB Signing Code
   4    Copyright (C) Jeremy Allison 2003.
   5    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2002-2003
   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 2 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, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 /* Lookup a packet's MID (multiplex id) and figure out it's sequence number */
  25 struct outstanding_packet_lookup {
  26         uint16 mid;
  27         uint32 reply_seq_num;
  28         struct outstanding_packet_lookup *prev, *next;
  29 };
  30
  31 struct smb_basic_signing_context {
  32         DATA_BLOB mac_key;
  33         uint32 send_seq_num;
  34         struct outstanding_packet_lookup *outstanding_packet_list;
  35 };
  36
  37 static BOOL store_sequence_for_reply(struct outstanding_packet_lookup **list,
  38                                      uint16 mid, uint32 reply_seq_num)
  39 {
  40         struct outstanding_packet_lookup *t;
  41
  42         /* Ensure we only add a mid once. */
  43         for (t = *list; t; t = t->next) {
  44                 if (t->mid == mid) {
  45                         return False;
  46                 }
  47         }
  48
  49         t = SMB_XMALLOC_P(struct outstanding_packet_lookup);
  50         ZERO_STRUCTP(t);
  51
  52         t->mid = mid;
  53         t->reply_seq_num = reply_seq_num;
  54
  55         /*
  56          * Add to the *start* of the list not the end of the list.
  57          * This ensures that the *last* send sequence with this mid
  58          * is returned by preference.
  59          * This can happen if the mid wraps and one of the early
  60          * mid numbers didn't get a reply and is still lurking on
  61          * the list. JRA. Found by Fran Fabrizio <fran@cis.uab.edu>.
  62          */
  63
  64         DLIST_ADD(*list, t);
  65         DEBUG(10,("store_sequence_for_reply: stored seq = %u mid = %u\n",
  66                         (unsigned int)reply_seq_num, (unsigned int)mid ));
  67         return True;
  68 }
  69
  70 static BOOL get_sequence_for_reply(struct outstanding_packet_lookup **list,
  71                                    uint16 mid, uint32 *reply_seq_num)
  72 {
  73         struct outstanding_packet_lookup *t;
  74
  75         for (t = *list; t; t = t->next) {
  76                 if (t->mid == mid) {
  77                         *reply_seq_num = t->reply_seq_num;
  78                         DEBUG(10,("get_sequence_for_reply: found seq = %u mid = %u\n",
  79                                 (unsigned int)t->reply_seq_num, (unsigned int)t->mid ));
  80                         DLIST_REMOVE(*list, t);
  81                         SAFE_FREE(t);
  82                         return True;
  83                 }
  84         }
  85         return False;
  86 }
  87
  88 /***********************************************************
  89  SMB signing - Common code before we set a new signing implementation
  90 ************************************************************/
  91
  92 static BOOL cli_set_smb_signing_common(struct cli_state *cli)
  93 {
  94         if (!cli->sign_info.negotiated_smb_signing
  95             && !cli->sign_info.mandatory_signing) {
  96                 return False;
  97         }
  98
  99         if (cli->sign_info.doing_signing) {
 100                 return False;
 101         }
 102
 103         if (cli->sign_info.free_signing_context)
 104                 cli->sign_info.free_signing_context(&cli->sign_info);
 105
 106         /* These calls are INCOMPATIBLE with SMB signing */
 107         cli->readbraw_supported = False;
 108         cli->writebraw_supported = False;
 109
 110         return True;
 111 }
 112
 113 /***********************************************************
 114  SMB signing - Common code for 'real' implementations
 115 ************************************************************/
 116
 117 static BOOL set_smb_signing_real_common(struct smb_sign_info *si)
 118 {
 119         if (si->mandatory_signing) {
 120                 DEBUG(5, ("Mandatory SMB signing enabled!\n"));
 121         }
 122
 123         si->doing_signing = True;
 124         DEBUG(5, ("SMB signing enabled!\n"));
 125
 126         return True;
 127 }
 128
 129 static void mark_packet_signed(char *outbuf)
 130 {
 131         uint16 flags2;
 132         flags2 = SVAL(outbuf,smb_flg2);
 133         flags2 |= FLAGS2_SMB_SECURITY_SIGNATURES;
 134         SSVAL(outbuf,smb_flg2, flags2);
 135 }
 136
 137 /***********************************************************
 138  SMB signing - NULL implementation - calculate a MAC to send.
 139 ************************************************************/
 140
 141 static void null_sign_outgoing_message(char *outbuf, struct smb_sign_info *si)
 142 {
 143         /* we can't zero out the sig, as we might be trying to send a
 144            session request - which is NBT-level, not SMB level and doesn't
 145            have the field */
 146         return;
 147 }
 148
 149 /***********************************************************
 150  SMB signing - NULL implementation - check a MAC sent by server.
 151 ************************************************************/
 152
 153 static BOOL null_check_incoming_message(char *inbuf, struct smb_sign_info *si, BOOL must_be_ok)
 154 {
 155         return True;
 156 }
 157
 158 /***********************************************************
 159  SMB signing - NULL implementation - free signing context
 160 ************************************************************/
 161
 162 static void null_free_signing_context(struct smb_sign_info *si)
 163 {
 164         return;
 165 }
 166
 167 /**
 168  SMB signing - NULL implementation - setup the MAC key.
 169
 170  @note Used as an initialisation only - it will not correctly
 171        shut down a real signing mechanism
 172 */
 173
 174 static BOOL null_set_signing(struct smb_sign_info *si)
 175 {
 176         si->signing_context = NULL;
 177
 178         si->sign_outgoing_message = null_sign_outgoing_message;
 179         si->check_incoming_message = null_check_incoming_message;
 180         si->free_signing_context = null_free_signing_context;
 181
 182         return True;
 183 }
 184
 185 /**
 186  * Free the signing context
 187  */
 188
 189 static void free_signing_context(struct smb_sign_info *si)
 190 {
 191         if (si->free_signing_context) {
 192                 si->free_signing_context(si);
 193                 si->signing_context = NULL;
 194         }
 195
 196         null_set_signing(si);
 197 }
 198
 199
 200 static BOOL signing_good(char *inbuf, struct smb_sign_info *si, BOOL good, uint32 seq, BOOL must_be_ok)
 201 {
 202         if (good) {
 203
 204                 if (!si->doing_signing) {
 205                         si->doing_signing = True;
 206                 }
 207
 208                 if (!si->seen_valid) {
 209                         si->seen_valid = True;
 210                 }
 211
 212         } else {
 213                 if (!si->mandatory_signing && !si->seen_valid) {
 214
 215                         if (!must_be_ok) {
 216                                 return True;
 217                         }
 218                         /* Non-mandatory signing - just turn off if this is the first bad packet.. */
 219                         DEBUG(5, ("srv_check_incoming_message: signing negotiated but not required and peer\n"
 220                                   "isn't sending correct signatures. Turning off.\n"));
 221                         si->negotiated_smb_signing = False;
 222                         si->allow_smb_signing = False;
 223                         si->doing_signing = False;
 224                         free_signing_context(si);
 225                         return True;
 226                 } else if (!must_be_ok) {
 227                         /* This packet is known to be unsigned */
 228                         return True;
 229                 } else {
 230                         /* Mandatory signing or bad packet after signing started - fail and disconnect. */
 231                         if (seq)
 232                                 DEBUG(0, ("signing_good: BAD SIG: seq %u\n", (unsigned int)seq));
 233                         return False;
 234                 }
 235         }
 236         return True;
 237 }
 238
 239 /***********************************************************
 240  SMB signing - Simple implementation - calculate a MAC on the packet
 241 ************************************************************/
 242
 243 static void simple_packet_signature(struct smb_basic_signing_context *data,
 244                                     const uchar *buf, uint32 seq_number,
 245                                     unsigned char calc_md5_mac[16])
 246 {
 247         const size_t offset_end_of_sig = (smb_ss_field + 8);
 248         unsigned char sequence_buf[8];
 249         struct MD5Context md5_ctx;
 250 #if 0
 251         /* JRA - apparently this is incorrect. */
 252         unsigned char key_buf[16];
 253 #endif
 254
 255         /*
 256          * Firstly put the sequence number into the first 4 bytes.
 257          * and zero out the next 4 bytes.
 258          *
 259          * We do this here, to avoid modifying the packet.
 260          */
 261
 262         DEBUG(10,("simple_packet_signature: sequence number %u\n", seq_number ));
 263
 264         SIVAL(sequence_buf, 0, seq_number);
 265         SIVAL(sequence_buf, 4, 0);
 266
 267         /* Calculate the 16 byte MAC - but don't alter the data in the
 268            incoming packet.
 269
 270            This makes for a bit of fussing about, but it's not too bad.
 271         */
 272         MD5Init(&md5_ctx);
 273
 274         /* intialise with the key */
 275         MD5Update(&md5_ctx, data->mac_key.data, data->mac_key.length);
 276 #if 0
 277         /* JRA - apparently this is incorrect. */
 278         /* NB. When making and verifying SMB signatures, Windows apparently
 279                 zero-pads the key to 128 bits if it isn't long enough.
 280                 From Nalin Dahyabhai <nalin@redhat.com> */
 281         if (data->mac_key.length < sizeof(key_buf)) {
 282                 memset(key_buf, 0, sizeof(key_buf));
 283                 MD5Update(&md5_ctx, key_buf, sizeof(key_buf) - data->mac_key.length);
 284         }
 285 #endif
 286
 287         /* copy in the first bit of the SMB header */
 288         MD5Update(&md5_ctx, buf + 4, smb_ss_field - 4);
 289
 290         /* copy in the sequence number, instead of the signature */
 291         MD5Update(&md5_ctx, sequence_buf, sizeof(sequence_buf));
 292
 293         /* copy in the rest of the packet in, skipping the signature */
 294         MD5Update(&md5_ctx, buf + offset_end_of_sig,
 295                   smb_len(buf) - (offset_end_of_sig - 4));
 296
 297         /* calculate the MD5 sig */
 298         MD5Final(calc_md5_mac, &md5_ctx);
 299 }
 300
 301
 302 /***********************************************************
 303  SMB signing - Client implementation - send the MAC.
 304 ************************************************************/
 305
 306 static void client_sign_outgoing_message(char *outbuf, struct smb_sign_info *si)
 307 {
 308         unsigned char calc_md5_mac[16];
 309         struct smb_basic_signing_context *data = si->signing_context;
 310
 311         if (!si->doing_signing)
 312                 return;
 313
 314         /* JRA Paranioa test - we should be able to get rid of this... */
 315         if (smb_len(outbuf) < (smb_ss_field + 8 - 4)) {
 316                 DEBUG(1, ("client_sign_outgoing_message: Logic error. Can't check signature on short packet! smb_len = %u\n",
 317                                         smb_len(outbuf) ));
 318                 abort();
 319         }
 320
 321         /* mark the packet as signed - BEFORE we sign it...*/
 322         mark_packet_signed(outbuf);
 323
 324         simple_packet_signature(data, (const unsigned char *)outbuf,
 325                                 data->send_seq_num, calc_md5_mac);
 326
 327         DEBUG(10, ("client_sign_outgoing_message: sent SMB signature of\n"));
 328         dump_data(10, (const char *)calc_md5_mac, 8);
 329
 330         memcpy(&outbuf[smb_ss_field], calc_md5_mac, 8);
 331
 332 /*      cli->outbuf[smb_ss_field+2]=0;
 333         Uncomment this to test if the remote server actually verifies signatures...*/
 334
 335         data->send_seq_num += 2;
 336 }
 337
 338 /***********************************************************
 339  SMB signing - Client implementation - check a MAC sent by server.
 340 ************************************************************/
 341
 342 static BOOL client_check_incoming_message(char *inbuf, struct smb_sign_info *si, BOOL must_be_ok)
 343 {
 344         BOOL good;
 345         uint32 reply_seq_number;
 346         unsigned char calc_md5_mac[16];
 347         unsigned char *server_sent_mac;
 348
 349         struct smb_basic_signing_context *data = si->signing_context;
 350
 351         if (!si->doing_signing)
 352                 return True;
 353
 354         if (smb_len(inbuf) < (smb_ss_field + 8 - 4)) {
 355                 DEBUG(1, ("client_check_incoming_message: Can't check signature on short packet! smb_len = %u\n", smb_len(inbuf)));
 356                 return False;
 357         }
 358
 359         reply_seq_number = data->send_seq_num - 1;
 360         simple_packet_signature(data, (const unsigned char *)inbuf,
 361                                 reply_seq_number, calc_md5_mac);
 362
 363         server_sent_mac = (unsigned char *)&inbuf[smb_ss_field];
 364         good = (memcmp(server_sent_mac, calc_md5_mac, 8) == 0);
 365
 366         if (!good) {
 367                 DEBUG(5, ("client_check_incoming_message: BAD SIG: wanted SMB signature of\n"));
 368                 dump_data(5, (const char *)calc_md5_mac, 8);
 369
 370                 DEBUG(5, ("client_check_incoming_message: BAD SIG: got SMB signature of\n"));
 371                 dump_data(5, (const char *)server_sent_mac, 8);
 372 #if 1 /* JRATEST */
 373                 {
 374                         int i;
 375                         for (i = -5; i < 5; i++) {
 376                                 simple_packet_signature(data, (const unsigned char *)inbuf, reply_seq_number+i, calc_md5_mac);
 377                                 if (memcmp(server_sent_mac, calc_md5_mac, 8) == 0) {
 378                                         DEBUG(0,("client_check_incoming_message: out of seq. seq num %u matches. \
 379 We were expecting seq %u\n", reply_seq_number+i, reply_seq_number ));
 380                                         break;
 381                                 }
 382                         }
 383                 }
 384 #endif /* JRATEST */
 385
 386         } else {
 387                 DEBUG(10, ("client_check_incoming_message: seq %u: got good SMB signature of\n", (unsigned int)reply_seq_number));
 388                 dump_data(10, (const char *)server_sent_mac, 8);
 389         }
 390         return signing_good(inbuf, si, good, reply_seq_number, must_be_ok);
 391 }
 392
 393 /***********************************************************
 394  SMB signing - Simple implementation - free signing context
 395 ************************************************************/
 396
 397 static void simple_free_signing_context(struct smb_sign_info *si)
 398 {
 399         struct smb_basic_signing_context *data = si->signing_context;
 400         struct outstanding_packet_lookup *list;
 401         struct outstanding_packet_lookup *next;
 402
 403         for (list = data->outstanding_packet_list; list; list = next) {
 404                 next = list->next;
 405                 DLIST_REMOVE(data->outstanding_packet_list, list);
 406                 SAFE_FREE(list);
 407         }
 408
 409         data_blob_free(&data->mac_key);
 410
 411         SAFE_FREE(si->signing_context);
 412
 413         return;
 414 }
 415
 416 /***********************************************************
 417  SMB signing - Simple implementation - setup the MAC key.
 418 ************************************************************/
 419
 420 BOOL cli_simple_set_signing(struct cli_state *cli,
 421                             const DATA_BLOB user_session_key,
 422                             const DATA_BLOB response)
 423 {
 424         struct smb_basic_signing_context *data;
 425
 426         if (!user_session_key.length)
 427                 return False;
 428
 429         if (!cli_set_smb_signing_common(cli)) {
 430                 return False;
 431         }
 432
 433         if (!set_smb_signing_real_common(&cli->sign_info)) {
 434                 return False;
 435         }
 436
 437         data = SMB_XMALLOC_P(struct smb_basic_signing_context);
 438         memset(data, '\0', sizeof(*data));
 439
 440         cli->sign_info.signing_context = data;
 441
 442         data->mac_key = data_blob(NULL, response.length + user_session_key.length);
 443
 444         memcpy(&data->mac_key.data[0], user_session_key.data, user_session_key.length);
 445
 446         DEBUG(10, ("cli_simple_set_signing: user_session_key\n"));
 447         dump_data(10, (const char *)user_session_key.data, user_session_key.length);
 448
 449         if (response.length) {
 450                 memcpy(&data->mac_key.data[user_session_key.length],response.data, response.length);
 451                 DEBUG(10, ("cli_simple_set_signing: response_data\n"));
 452                 dump_data(10, (const char *)response.data, response.length);
 453         } else {
 454                 DEBUG(10, ("cli_simple_set_signing: NULL response_data\n"));
 455         }
 456
 457         dump_data_pw("MAC ssession key is:\n", data->mac_key.data, data->mac_key.length);
 458
 459         /* Initialise the sequence number */
 460         data->send_seq_num = 0;
 461
 462         /* Initialise the list of outstanding packets */
 463         data->outstanding_packet_list = NULL;
 464
 465         cli->sign_info.sign_outgoing_message = client_sign_outgoing_message;
 466         cli->sign_info.check_incoming_message = client_check_incoming_message;
 467         cli->sign_info.free_signing_context = simple_free_signing_context;
 468
 469         return True;
 470 }
 471
 472 /***********************************************************
 473  SMB signing - TEMP implementation - calculate a MAC to send.
 474 ************************************************************/
 475
 476 static void temp_sign_outgoing_message(char *outbuf, struct smb_sign_info *si)
 477 {
 478         /* mark the packet as signed - BEFORE we sign it...*/
 479         mark_packet_signed(outbuf);
 480
 481         /* I wonder what BSRSPYL stands for - but this is what MS
 482            actually sends! */
 483         memcpy(&outbuf[smb_ss_field], "BSRSPYL ", 8);
 484         return;
 485 }
 486
 487 /***********************************************************
 488  SMB signing - TEMP implementation - check a MAC sent by server.
 489 ************************************************************/
 490
 491 static BOOL temp_check_incoming_message(char *inbuf, struct smb_sign_info *si, BOOL foo)
 492 {
 493         return True;
 494 }
 495
 496 /***********************************************************
 497  SMB signing - TEMP implementation - free signing context
 498 ************************************************************/
 499
 500 static void temp_free_signing_context(struct smb_sign_info *si)
 501 {
 502         return;
 503 }
 504
 505 /***********************************************************
 506  SMB signing - NULL implementation - setup the MAC key.
 507 ************************************************************/
 508
 509 BOOL cli_null_set_signing(struct cli_state *cli)
 510 {
 511         return null_set_signing(&cli->sign_info);
 512 }
 513
 514 /***********************************************************
 515  SMB signing - temp implementation - setup the MAC key.
 516 ************************************************************/
 517
 518 BOOL cli_temp_set_signing(struct cli_state *cli)
 519 {
 520         if (!cli_set_smb_signing_common(cli)) {
 521                 return False;
 522         }
 523
 524         cli->sign_info.signing_context = NULL;
 525
 526         cli->sign_info.sign_outgoing_message = temp_sign_outgoing_message;
 527         cli->sign_info.check_incoming_message = temp_check_incoming_message;
 528         cli->sign_info.free_signing_context = temp_free_signing_context;
 529
 530         return True;
 531 }
 532
 533 void cli_free_signing_context(struct cli_state *cli)
 534 {
 535         free_signing_context(&cli->sign_info);
 536 }
 537
 538 /**
 539  * Sign a packet with the current mechanism
 540  */
 541
 542 void cli_calculate_sign_mac(struct cli_state *cli)
 543 {
 544         cli->sign_info.sign_outgoing_message(cli->outbuf, &cli->sign_info);
 545 }
 546
 547 /**
 548  * Check a packet with the current mechanism
 549  * @return False if we had an established signing connection
 550  *         which had a bad checksum, True otherwise.
 551  */
 552
 553 BOOL cli_check_sign_mac(struct cli_state *cli)
 554 {
 555         if (!cli->sign_info.check_incoming_message(cli->inbuf, &cli->sign_info, True)) {
 556                 free_signing_context(&cli->sign_info);
 557                 return False;
 558         }
 559         return True;
 560 }
 561
 562 /***********************************************************
 563  SMB signing - Server implementation - send the MAC.
 564 ************************************************************/
 565
 566 static void srv_sign_outgoing_message(char *outbuf, struct smb_sign_info *si)
 567 {
 568         unsigned char calc_md5_mac[16];
 569         struct smb_basic_signing_context *data = si->signing_context;
 570         uint32 send_seq_number = data->send_seq_num-1;
 571         uint16 mid;
 572
 573         if (!si->doing_signing) {
 574                 return;
 575         }
 576
 577         /* JRA Paranioa test - we should be able to get rid of this... */
 578         if (smb_len(outbuf) < (smb_ss_field + 8 - 4)) {
 579                 DEBUG(1, ("srv_sign_outgoing_message: Logic error. Can't send signature on short packet! smb_len = %u\n",
 580                                         smb_len(outbuf) ));
 581                 abort();
 582         }
 583
 584         /* mark the packet as signed - BEFORE we sign it...*/
 585         mark_packet_signed(outbuf);
 586
 587         mid = SVAL(outbuf, smb_mid);
 588
 589         /* See if this is a reply for a deferred packet. */
 590         get_sequence_for_reply(&data->outstanding_packet_list, mid, &send_seq_number);
 591
 592         simple_packet_signature(data, (const unsigned char *)outbuf, send_seq_number, calc_md5_mac);
 593
 594         DEBUG(10, ("srv_sign_outgoing_message: seq %u: sent SMB signature of\n", (unsigned int)send_seq_number));
 595         dump_data(10, (const char *)calc_md5_mac, 8);
 596
 597         memcpy(&outbuf[smb_ss_field], calc_md5_mac, 8);
 598
 599 /*      cli->outbuf[smb_ss_field+2]=0;
 600         Uncomment this to test if the remote client actually verifies signatures...*/
 601 }
 602
 603 /***********************************************************
 604  SMB signing - Server implementation - check a MAC sent by server.
 605 ************************************************************/
 606
 607 static BOOL srv_check_incoming_message(char *inbuf, struct smb_sign_info *si, BOOL must_be_ok)
 608 {
 609         BOOL good;
 610         struct smb_basic_signing_context *data = si->signing_context;
 611         uint32 reply_seq_number = data->send_seq_num;
 612         uint32 saved_seq;
 613         unsigned char calc_md5_mac[16];
 614         unsigned char *server_sent_mac;
 615         uint mid;
 616
 617         if (!si->doing_signing)
 618                 return True;
 619
 620         if (smb_len(inbuf) < (smb_ss_field + 8 - 4)) {
 621                 DEBUG(1, ("srv_check_incoming_message: Can't check signature on short packet! smb_len = %u\n", smb_len(inbuf)));
 622                 return False;
 623         }
 624
 625         mid = SVAL(inbuf, smb_mid);
 626
 627         /* We always increment the sequence number. */
 628         data->send_seq_num += 2;
 629
 630         saved_seq = reply_seq_number;
 631         simple_packet_signature(data, (const unsigned char *)inbuf, reply_seq_number, calc_md5_mac);
 632
 633         server_sent_mac = (unsigned char *)&inbuf[smb_ss_field];
 634         good = (memcmp(server_sent_mac, calc_md5_mac, 8) == 0);
 635
 636         if (!good) {
 637
 638                 if (saved_seq) {
 639                         DEBUG(0, ("srv_check_incoming_message: BAD SIG: seq %u wanted SMB signature of\n",
 640                                         (unsigned int)saved_seq));
 641                         dump_data(5, (const char *)calc_md5_mac, 8);
 642
 643                         DEBUG(0, ("srv_check_incoming_message: BAD SIG: seq %u got SMB signature of\n",
 644                                                 (unsigned int)reply_seq_number));
 645                         dump_data(5, (const char *)server_sent_mac, 8);
 646                 }
 647
 648 #if 1 /* JRATEST */
 649                 {
 650                         int i;
 651                         reply_seq_number -= 5;
 652                         for (i = 0; i < 10; i++, reply_seq_number++) {
 653                                 simple_packet_signature(data, (const unsigned char *)inbuf, reply_seq_number, calc_md5_mac);
 654                                 if (memcmp(server_sent_mac, calc_md5_mac, 8) == 0) {
 655                                         DEBUG(0,("srv_check_incoming_message: out of seq. seq num %u matches. \
 656 We were expecting seq %u\n", reply_seq_number, saved_seq ));
 657                                         break;
 658                                 }
 659                         }
 660                 }
 661 #endif /* JRATEST */
 662
 663         } else {
 664                 DEBUG(10, ("srv_check_incoming_message: seq %u: (current is %u) got good SMB signature of\n", (unsigned int)reply_seq_number, (unsigned int)data->send_seq_num));
 665                 dump_data(10, (const char *)server_sent_mac, 8);
 666         }
 667
 668         return (signing_good(inbuf, si, good, saved_seq, must_be_ok));
 669 }
 670
 671 /***********************************************************
 672  SMB signing - server API's.
 673 ************************************************************/
 674
 675 static struct smb_sign_info srv_sign_info = {
 676         null_sign_outgoing_message,
 677         null_check_incoming_message,
 678         null_free_signing_context,
 679         NULL,
 680         False,
 681         False,
 682         False,
 683         False
 684 };
 685
 686 /***********************************************************
 687  Turn signing off or on for oplock break code.
 688 ************************************************************/
 689
 690 BOOL srv_oplock_set_signing(BOOL onoff)
 691 {
 692         BOOL ret = srv_sign_info.doing_signing;
 693         srv_sign_info.doing_signing = onoff;
 694         return ret;
 695 }
 696
 697 /***********************************************************
 698  Called to validate an incoming packet from the client.
 699 ************************************************************/
 700
 701 BOOL srv_check_sign_mac(char *inbuf, BOOL must_be_ok)
 702 {
 703         /* Check if it's a session keepalive. */
 704         if(CVAL(inbuf,0) == SMBkeepalive)
 705                 return True;
 706
 707         return srv_sign_info.check_incoming_message(inbuf, &srv_sign_info, must_be_ok);
 708 }
 709
 710 /***********************************************************
 711  Called to sign an outgoing packet to the client.
 712 ************************************************************/
 713
 714 void srv_calculate_sign_mac(char *outbuf)
 715 {
 716         /* Check if it's a session keepalive. */
 717         /* JRA Paranioa test - do we ever generate these in the server ? */
 718         if(CVAL(outbuf,0) == SMBkeepalive)
 719                 return;
 720
 721         srv_sign_info.sign_outgoing_message(outbuf, &srv_sign_info);
 722 }
 723
 724 /***********************************************************
 725  Called by server to defer an outgoing packet.
 726 ************************************************************/
 727
 728 void srv_defer_sign_response(uint16 mid)
 729 {
 730         struct smb_basic_signing_context *data;
 731
 732         if (!srv_sign_info.doing_signing)
 733                 return;
 734
 735         data = (struct smb_basic_signing_context *)srv_sign_info.signing_context;
 736
 737         if (!data)
 738                 return;
 739
 740         /*
 741          * Ensure we only store this mid reply once...
 742          */
 743
 744         store_sequence_for_reply(&data->outstanding_packet_list, mid,
 745                                  data->send_seq_num-1);
 746 }
 747
 748 /***********************************************************
 749  Called to remove sequence records when a deferred packet is
 750  cancelled by mid. This should never find one....
 751 ************************************************************/
 752
 753 void srv_cancel_sign_response(uint16 mid)
 754 {
 755         struct smb_basic_signing_context *data;
 756         uint32 dummy_seq;
 757
 758         if (!srv_sign_info.doing_signing)
 759                 return;
 760
 761         data = (struct smb_basic_signing_context *)srv_sign_info.signing_context;
 762
 763         if (!data)
 764                 return;
 765
 766         DEBUG(10,("srv_cancel_sign_response: for mid %u\n", (unsigned int)mid ));
 767
 768         while (get_sequence_for_reply(&data->outstanding_packet_list, mid, &dummy_seq))
 769                 ;
 770 }
 771
 772 /***********************************************************
 773  Called by server negprot when signing has been negotiated.
 774 ************************************************************/
 775
 776 void srv_set_signing_negotiated(void)
 777 {
 778         srv_sign_info.allow_smb_signing = True;
 779         srv_sign_info.negotiated_smb_signing = True;
 780         if (lp_server_signing() == Required)
 781                 srv_sign_info.mandatory_signing = True;
 782
 783         srv_sign_info.sign_outgoing_message = temp_sign_outgoing_message;
 784         srv_sign_info.check_incoming_message = temp_check_incoming_message;
 785         srv_sign_info.free_signing_context = temp_free_signing_context;
 786 }
 787
 788 /***********************************************************
 789  Returns whether signing is active. We can't use sendfile or raw
 790  reads/writes if it is.
 791 ************************************************************/
 792
 793 BOOL srv_is_signing_active(void)
 794 {
 795         return srv_sign_info.doing_signing;
 796 }
 797
 798
 799 /***********************************************************
 800  Returns whether signing is negotiated. We can't use it unless it was
 801  in the negprot.
 802 ************************************************************/
 803
 804 BOOL srv_is_signing_negotiated(void)
 805 {
 806         return srv_sign_info.negotiated_smb_signing;
 807 }
 808
 809 /***********************************************************
 810  Returns whether signing is actually happening
 811 ************************************************************/
 812
 813 BOOL srv_signing_started(void)
 814 {
 815         struct smb_basic_signing_context *data;
 816
 817         if (!srv_sign_info.doing_signing) {
 818                 return False;
 819         }
 820
 821         data = (struct smb_basic_signing_context *)srv_sign_info.signing_context;
 822         if (!data)
 823                 return False;
 824
 825         if (data->send_seq_num == 0) {
 826                 return False;
 827         }
 828
 829         return True;
 830 }
 831
 832 /***********************************************************
 833  Turn on signing from this packet onwards.
 834 ************************************************************/
 835
 836 void srv_set_signing(const DATA_BLOB user_session_key, const DATA_BLOB response)
 837 {
 838         struct smb_basic_signing_context *data;
 839
 840         if (!user_session_key.length)
 841                 return;
 842
 843         if (!srv_sign_info.negotiated_smb_signing && !srv_sign_info.mandatory_signing) {
 844                 DEBUG(5,("srv_set_signing: signing negotiated = %u, mandatory_signing = %u. Not allowing smb signing.\n",
 845                         (unsigned int)srv_sign_info.negotiated_smb_signing,
 846                         (unsigned int)srv_sign_info.mandatory_signing ));
 847                 return;
 848         }
 849
 850         /* Once we've turned on, ignore any more sessionsetups. */
 851         if (srv_sign_info.doing_signing) {
 852                 return;
 853         }
 854
 855         if (srv_sign_info.free_signing_context)
 856                 srv_sign_info.free_signing_context(&srv_sign_info);
 857
 858         srv_sign_info.doing_signing = True;
 859
 860         data = SMB_XMALLOC_P(struct smb_basic_signing_context);
 861         memset(data, '\0', sizeof(*data));
 862
 863         srv_sign_info.signing_context = data;
 864
 865         data->mac_key = data_blob(NULL, response.length + user_session_key.length);
 866
 867         memcpy(&data->mac_key.data[0], user_session_key.data, user_session_key.length);
 868         if (response.length)
 869                 memcpy(&data->mac_key.data[user_session_key.length],response.data, response.length);
 870
 871         dump_data_pw("MAC ssession key is:\n", data->mac_key.data, data->mac_key.length);
 872
 873         DEBUG(3,("srv_set_signing: turning on SMB signing: signing negotiated = %s, mandatory_signing = %s.\n",
 874                                 BOOLSTR(srv_sign_info.negotiated_smb_signing),
 875                                 BOOLSTR(srv_sign_info.mandatory_signing) ));
 876
 877         /* Initialise the sequence number */
 878         data->send_seq_num = 0;
 879
 880         /* Initialise the list of outstanding packets */
 881         data->outstanding_packet_list = NULL;
 882
 883         srv_sign_info.sign_outgoing_message = srv_sign_outgoing_message;
 884         srv_sign_info.check_incoming_message = srv_check_incoming_message;
 885         srv_sign_info.free_signing_context = simple_free_signing_context;
 886 }