source4/auth/ntlmssp/ntlmssp_sign.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  Version 3.0
   4  *  NTLMSSP Signing routines
   5  *  Copyright (C) Luke Kenneth Casson Leighton 1996-2001
   6  *  Copyright (C) Andrew Bartlett <abartlet@samba.org> 2003-2005
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 3 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include "includes.h"
  23 #include "auth/ntlmssp/ntlmssp.h"
  24 #include "../libcli/auth/libcli_auth.h"
  25 #include "../lib/crypto/crypto.h"
  26 #include "auth/gensec/gensec.h"
  27
  28 #define CLI_SIGN "session key to client-to-server signing key magic constant"
  29 #define CLI_SEAL "session key to client-to-server sealing key magic constant"
  30 #define SRV_SIGN "session key to server-to-client signing key magic constant"
  31 #define SRV_SEAL "session key to server-to-client sealing key magic constant"
  32
  33 /**
  34  * Some notes on the NTLM2 code:
  35  *
  36  * NTLM2 is a AEAD system.  This means that the data encrypted is not
  37  * all the data that is signed.  In DCE-RPC case, the headers of the
  38  * DCE-RPC packets are also signed.  This prevents some of the
  39  * fun-and-games one might have by changing them.
  40  *
  41  */
  42
  43 static void calc_ntlmv2_key(TALLOC_CTX *mem_ctx,
  44                             DATA_BLOB *subkey,
  45                             DATA_BLOB session_key,
  46                             const char *constant)
  47 {
  48         struct MD5Context ctx3;
  49         *subkey = data_blob_talloc(mem_ctx, NULL, 16);
  50         MD5Init(&ctx3);
  51         MD5Update(&ctx3, session_key.data, session_key.length);
  52         MD5Update(&ctx3, (const uint8_t *)constant, strlen(constant)+1);
  53         MD5Final(subkey->data, &ctx3);
  54 }
  55
  56 enum ntlmssp_direction {
  57         NTLMSSP_SEND,
  58         NTLMSSP_RECEIVE
  59 };
  60
  61 static NTSTATUS ntlmssp_make_packet_signature(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
  62                                               TALLOC_CTX *sig_mem_ctx,
  63                                               const uint8_t *data, size_t length,
  64                                               const uint8_t *whole_pdu, size_t pdu_length,
  65                                               enum ntlmssp_direction direction,
  66                                               DATA_BLOB *sig, bool encrypt_sig)
  67 {
  68         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
  69
  70                 HMACMD5Context ctx;
  71                 uint8_t digest[16];
  72                 uint8_t seq_num[4];
  73
  74                 *sig = data_blob_talloc(sig_mem_ctx, NULL, NTLMSSP_SIG_SIZE);
  75                 if (!sig->data) {
  76                         return NT_STATUS_NO_MEMORY;
  77                 }
  78
  79                 switch (direction) {
  80                 case NTLMSSP_SEND:
  81                         SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.send_seq_num);
  82                         gensec_ntlmssp_state->crypt.ntlm2.send_seq_num++;
  83                         hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
  84                                                  gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length, &ctx);
  85                         break;
  86                 case NTLMSSP_RECEIVE:
  87                         SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num);
  88                         gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num++;
  89                         hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
  90                                                  gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length, &ctx);
  91                         break;
  92                 }
  93                 hmac_md5_update(seq_num, sizeof(seq_num), &ctx);
  94                 hmac_md5_update(whole_pdu, pdu_length, &ctx);
  95                 hmac_md5_final(digest, &ctx);
  96
  97                 if (encrypt_sig && gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
  98                         switch (direction) {
  99                         case NTLMSSP_SEND:
 100                                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, digest, 8);
 101                                 break;
 102                         case NTLMSSP_RECEIVE:
 103                                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, digest, 8);
 104                                 break;
 105                         }
 106                 }
 107
 108                 SIVAL(sig->data, 0, NTLMSSP_SIGN_VERSION);
 109                 memcpy(sig->data + 4, digest, 8);
 110                 memcpy(sig->data + 12, seq_num, 4);
 111
 112                 DEBUG(10, ("NTLM2: created signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
 113                 dump_data(11, sig->data, sig->length);
 114
 115         } else {
 116                 uint32_t crc;
 117                 crc = crc32_calc_buffer(data, length);
 118                 if (!msrpc_gen(sig_mem_ctx,
 119                                sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
 120                         return NT_STATUS_NO_MEMORY;
 121                 }
 122                 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
 123
 124                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
 125
 126                 DEBUG(10, ("NTLM1: created signature over %llu bytes of input:\n", (unsigned long long)length));
 127                 dump_data(11, sig->data, sig->length);
 128         }
 129         return NT_STATUS_OK;
 130 }
 131
 132 NTSTATUS ntlmssp_sign_packet(struct gensec_ntlmssp_state *ntlmssp_state,
 133                              TALLOC_CTX *sig_mem_ctx,
 134                              const uint8_t *data, size_t length,
 135                              const uint8_t *whole_pdu, size_t pdu_length,
 136                              DATA_BLOB *sig)
 137 {
 138         return ntlmssp_make_packet_signature(ntlmssp_state,
 139                                              sig_mem_ctx,
 140                                              data, length,
 141                                              whole_pdu, pdu_length,
 142                                              NTLMSSP_SEND, sig, true);
 143 }
 144
 145 /**
 146  * Check the signature of an incoming packet
 147  *
 148  */
 149
 150 NTSTATUS ntlmssp_check_packet(struct gensec_ntlmssp_state *ntlmssp_state,
 151                               TALLOC_CTX *sig_mem_ctx,
 152                               const uint8_t *data, size_t length,
 153                               const uint8_t *whole_pdu, size_t pdu_length,
 154                               const DATA_BLOB *sig)
 155 {
 156         DATA_BLOB local_sig;
 157         NTSTATUS nt_status;
 158
 159         if (!ntlmssp_state->session_key.length) {
 160                 DEBUG(3, ("NO session key, cannot check packet signature\n"));
 161                 return NT_STATUS_NO_USER_SESSION_KEY;
 162         }
 163
 164         nt_status = ntlmssp_make_packet_signature(ntlmssp_state, sig_mem_ctx,
 165                                                   data, length,
 166                                                   whole_pdu, pdu_length,
 167                                                   NTLMSSP_RECEIVE, &local_sig, true);
 168
 169         if (!NT_STATUS_IS_OK(nt_status)) {
 170                 DEBUG(0, ("NTLMSSP packet sig creation failed with %s\n", nt_errstr(nt_status)));
 171                 return nt_status;
 172         }
 173
 174         if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 175                 if (local_sig.length != sig->length ||
 176                     memcmp(local_sig.data,
 177                            sig->data, sig->length) != 0) {
 178
 179                         DEBUG(10, ("BAD SIG NTLM2: wanted signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
 180                         dump_data(10, local_sig.data, local_sig.length);
 181
 182                         DEBUG(10, ("BAD SIG: got signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
 183                         dump_data(10, sig->data, sig->length);
 184
 185                         data_blob_free(&local_sig);
 186                         return NT_STATUS_ACCESS_DENIED;
 187                 }
 188         } else {
 189                 if (local_sig.length != sig->length ||
 190                     memcmp(local_sig.data + 8,
 191                            sig->data + 8, sig->length - 8) != 0) {
 192                         DEBUG(10, ("BAD SIG NTLM1: wanted signature of %llu bytes of input:\n", (unsigned long long)length));
 193                         dump_data(5, local_sig.data, local_sig.length);
 194
 195                         DEBUG(10, ("BAD SIG: got signature of %llu bytes of input:\n", (unsigned long long)length));
 196                         dump_data(10, sig->data, sig->length);
 197
 198                         data_blob_free(&local_sig);
 199                         return NT_STATUS_ACCESS_DENIED;
 200                 }
 201         }
 202         dump_data_pw("checked ntlmssp signature\n", sig->data, sig->length);
 203
 204         data_blob_free(&local_sig);
 205         return NT_STATUS_OK;
 206 }
 207
 208
 209 /**
 210  * Seal data with the NTLMSSP algorithm
 211  *
 212  */
 213
 214 NTSTATUS ntlmssp_seal_packet(struct gensec_ntlmssp_state *ntlmssp_state,
 215                              TALLOC_CTX *sig_mem_ctx,
 216                              uint8_t *data, size_t length,
 217                              const uint8_t *whole_pdu, size_t pdu_length,
 218                              DATA_BLOB *sig)
 219 {
 220         NTSTATUS nt_status;
 221
 222         if (!ntlmssp_state->session_key.length) {
 223                 DEBUG(3, ("NO session key, cannot seal packet\n"));
 224                 return NT_STATUS_NO_USER_SESSION_KEY;
 225         }
 226
 227         DEBUG(10,("ntlmssp_seal_data: seal\n"));
 228         dump_data_pw("ntlmssp clear data\n", data, length);
 229         if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 230                 /* The order of these two operations matters - we must first seal the packet,
 231                    then seal the sequence number - this is because the send_seal_hash is not
 232                    constant, but is is rather updated with each iteration */
 233                 nt_status = ntlmssp_make_packet_signature(ntlmssp_state, sig_mem_ctx,
 234                                                           data, length,
 235                                                           whole_pdu, pdu_length,
 236                                                           NTLMSSP_SEND, sig, false);
 237                 arcfour_crypt_sbox(ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, data, length);
 238                 if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 239                         arcfour_crypt_sbox(ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, sig->data+4, 8);
 240                 }
 241         } else {
 242                 uint32_t crc;
 243                 crc = crc32_calc_buffer(data, length);
 244                 if (!msrpc_gen(sig_mem_ctx,
 245                                sig, "dddd", NTLMSSP_SIGN_VERSION, 0,
 246                                crc, ntlmssp_state->crypt.ntlm.seq_num)) {
 247                         return NT_STATUS_NO_MEMORY;
 248                 }
 249
 250                 /* The order of these two operations matters - we must
 251                    first seal the packet, then seal the sequence
 252                    number - this is because the ntlmssp_hash is not
 253                    constant, but is is rather updated with each
 254                    iteration */
 255
 256                 arcfour_crypt_sbox(ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
 257                 arcfour_crypt_sbox(ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
 258                 /* increment counter on send */
 259                 ntlmssp_state->crypt.ntlm.seq_num++;
 260                 nt_status = NT_STATUS_OK;
 261         }
 262         dump_data_pw("ntlmssp signature\n", sig->data, sig->length);
 263         dump_data_pw("ntlmssp sealed data\n", data, length);
 264
 265
 266         return nt_status;
 267 }
 268
 269 /**
 270  * Unseal data with the NTLMSSP algorithm
 271  *
 272  */
 273
 274 /*
 275   wrappers for the ntlmssp_*() functions
 276 */
 277 NTSTATUS gensec_ntlmssp_unseal_packet(struct gensec_security *gensec_security,
 278                                       TALLOC_CTX *sig_mem_ctx,
 279                                       uint8_t *data, size_t length,
 280                                       const uint8_t *whole_pdu, size_t pdu_length,
 281                                       const DATA_BLOB *sig)
 282 {
 283         NTSTATUS status;
 284         struct gensec_ntlmssp_context *gensec_ntlmssp =
 285                 talloc_get_type_abort(gensec_security->private_data,
 286                                       struct gensec_ntlmssp_context);
 287         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 288         if (!gensec_ntlmssp_state->session_key.length) {
 289                 DEBUG(3, ("NO session key, cannot unseal packet\n"));
 290                 return NT_STATUS_NO_USER_SESSION_KEY;
 291         }
 292
 293         dump_data_pw("ntlmssp sealed data\n", data, length);
 294         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 295                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, data, length);
 296         } else {
 297                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
 298         }
 299         dump_data_pw("ntlmssp clear data\n", data, length);
 300         status = gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx, data, length, whole_pdu, pdu_length, sig);
 301
 302         if (!NT_STATUS_IS_OK(status)) {
 303                 DEBUG(1, ("NTLMSSP packet check for unseal failed due to invalid signature on %llu bytes of input:\n", (unsigned long long)length));
 304         }
 305         return status;
 306 }
 307
 308 /**
 309    Initialise the state for NTLMSSP signing.
 310 */
 311 /* TODO: make this non-public */
 312 NTSTATUS ntlmssp_sign_init(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 313 {
 314         TALLOC_CTX *mem_ctx = talloc_new(gensec_ntlmssp_state);
 315
 316         if (!mem_ctx) {
 317                 return NT_STATUS_NO_MEMORY;
 318         }
 319
 320         DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
 321         debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
 322
 323         if (gensec_ntlmssp_state->session_key.length < 8) {
 324                 talloc_free(mem_ctx);
 325                 DEBUG(3, ("NO session key, cannot intialise signing\n"));
 326                 return NT_STATUS_NO_USER_SESSION_KEY;
 327         }
 328
 329         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
 330         {
 331                 DATA_BLOB weak_session_key = gensec_ntlmssp_state->session_key;
 332                 const char *send_sign_const;
 333                 const char *send_seal_const;
 334                 const char *recv_sign_const;
 335                 const char *recv_seal_const;
 336
 337                 DATA_BLOB send_seal_key;
 338                 DATA_BLOB recv_seal_key;
 339
 340                 switch (gensec_ntlmssp_state->role) {
 341                 case NTLMSSP_CLIENT:
 342                         send_sign_const = CLI_SIGN;
 343                         send_seal_const = CLI_SEAL;
 344                         recv_sign_const = SRV_SIGN;
 345                         recv_seal_const = SRV_SEAL;
 346                         break;
 347                 case NTLMSSP_SERVER:
 348                         send_sign_const = SRV_SIGN;
 349                         send_seal_const = SRV_SEAL;
 350                         recv_sign_const = CLI_SIGN;
 351                         recv_seal_const = CLI_SEAL;
 352                         break;
 353                 default:
 354                         talloc_free(mem_ctx);
 355                         return NT_STATUS_INTERNAL_ERROR;
 356                 }
 357
 358                 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 359                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
 360                 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 361                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
 362
 363                 /**
 364                    Weaken NTLMSSP keys to cope with down-level
 365                    clients, servers and export restrictions.
 366
 367                    We probably should have some parameters to control
 368                    this, once we get NTLM2 working.
 369                 */
 370
 371                 /* Key weakening was not performed on the master key
 372                  * for NTLM2 (in ntlmssp_weaken_keys()), but must be
 373                  * done on the encryption subkeys only.  That is why
 374                  * we don't have this code for the ntlmv1 case.
 375                  */
 376
 377                 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
 378
 379                 } else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
 380                         weak_session_key.length = 7;
 381                 } else { /* forty bits */
 382                         weak_session_key.length = 5;
 383                 }
 384                 dump_data_pw("NTLMSSP weakend master key:\n",
 385                              weak_session_key.data,
 386                              weak_session_key.length);
 387
 388                 /* SEND: sign key */
 389                 calc_ntlmv2_key(gensec_ntlmssp_state,
 390                                 &gensec_ntlmssp_state->crypt.ntlm2.send_sign_key,
 391                                 gensec_ntlmssp_state->session_key, send_sign_const);
 392                 dump_data_pw("NTLMSSP send sign key:\n",
 393                              gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
 394                              gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length);
 395
 396                 /* SEND: seal ARCFOUR pad */
 397                 calc_ntlmv2_key(mem_ctx,
 398                                 &send_seal_key,
 399                                 weak_session_key, send_seal_const);
 400                 dump_data_pw("NTLMSSP send seal key:\n",
 401                              send_seal_key.data,
 402                              send_seal_key.length);
 403                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state,
 404                              &send_seal_key);
 405                 dump_data_pw("NTLMSSP send sesl hash:\n",
 406                              gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox,
 407                              sizeof(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox));
 408
 409                 /* RECV: sign key */
 410                 calc_ntlmv2_key(gensec_ntlmssp_state,
 411                                 &gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key,
 412                                 gensec_ntlmssp_state->session_key, recv_sign_const);
 413                 dump_data_pw("NTLMSSP recv sign key:\n",
 414                              gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
 415                              gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length);
 416
 417                 /* RECV: seal ARCFOUR pad */
 418                 calc_ntlmv2_key(mem_ctx,
 419                                 &recv_seal_key,
 420                                 weak_session_key, recv_seal_const);
 421                 dump_data_pw("NTLMSSP recv seal key:\n",
 422                              recv_seal_key.data,
 423                              recv_seal_key.length);
 424                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state,
 425                              &recv_seal_key);
 426                 dump_data_pw("NTLMSSP receive seal hash:\n",
 427                              gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox,
 428                              sizeof(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox));
 429
 430                 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num = 0;
 431                 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = 0;
 432
 433         } else {
 434                 DATA_BLOB weak_session_key = ntlmssp_weakend_key(gensec_ntlmssp_state, mem_ctx);
 435                 DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));
 436
 437                 gensec_ntlmssp_state->crypt.ntlm.arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 438                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm.arcfour_state);
 439
 440                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm.arcfour_state,
 441                              &weak_session_key);
 442                 dump_data_pw("NTLMSSP hash:\n", gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox,
 443                              sizeof(gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox));
 444
 445                 gensec_ntlmssp_state->crypt.ntlm.seq_num = 0;
 446         }
 447
 448         talloc_free(mem_ctx);
 449         return NT_STATUS_OK;
 450 }
 451
 452 NTSTATUS gensec_ntlmssp_sign_packet(struct gensec_security *gensec_security,
 453                                     TALLOC_CTX *sig_mem_ctx,
 454                                     const uint8_t *data, size_t length,
 455                                     const uint8_t *whole_pdu, size_t pdu_length,
 456                                     DATA_BLOB *sig)
 457 {
 458         struct gensec_ntlmssp_context *gensec_ntlmssp =
 459                 talloc_get_type_abort(gensec_security->private_data,
 460                                       struct gensec_ntlmssp_context);
 461         NTSTATUS nt_status;
 462
 463         nt_status = ntlmssp_sign_packet(gensec_ntlmssp->ntlmssp_state,
 464                                         sig_mem_ctx,
 465                                         data, length,
 466                                         whole_pdu, pdu_length,
 467                                         sig);
 468
 469         return nt_status;
 470 }
 471
 472 NTSTATUS gensec_ntlmssp_check_packet(struct gensec_security *gensec_security,
 473                                      TALLOC_CTX *sig_mem_ctx,
 474                                      const uint8_t *data, size_t length,
 475                                      const uint8_t *whole_pdu, size_t pdu_length,
 476                                      const DATA_BLOB *sig)
 477 {
 478         struct gensec_ntlmssp_context *gensec_ntlmssp =
 479                 talloc_get_type_abort(gensec_security->private_data,
 480                                       struct gensec_ntlmssp_context);
 481         NTSTATUS nt_status;
 482
 483         nt_status = ntlmssp_check_packet(gensec_ntlmssp->ntlmssp_state,
 484                                          sig_mem_ctx,
 485                                          data, length,
 486                                          whole_pdu, pdu_length,
 487                                          sig);
 488
 489         return nt_status;
 490 }
 491
 492 NTSTATUS gensec_ntlmssp_seal_packet(struct gensec_security *gensec_security,
 493                                     TALLOC_CTX *sig_mem_ctx,
 494                                     uint8_t *data, size_t length,
 495                                     const uint8_t *whole_pdu, size_t pdu_length,
 496                                     DATA_BLOB *sig)
 497 {
 498         struct gensec_ntlmssp_context *gensec_ntlmssp =
 499                 talloc_get_type_abort(gensec_security->private_data,
 500                                       struct gensec_ntlmssp_context);
 501         NTSTATUS nt_status;
 502
 503         nt_status = ntlmssp_seal_packet(gensec_ntlmssp->ntlmssp_state,
 504                                         sig_mem_ctx,
 505                                         data, length,
 506                                         whole_pdu, pdu_length,
 507                                         sig);
 508
 509         return nt_status;
 510 }
 511
 512 size_t gensec_ntlmssp_sig_size(struct gensec_security *gensec_security, size_t data_size)
 513 {
 514         return NTLMSSP_SIG_SIZE;
 515 }
 516
 517 NTSTATUS gensec_ntlmssp_wrap(struct gensec_security *gensec_security,
 518                              TALLOC_CTX *sig_mem_ctx,
 519                              const DATA_BLOB *in,
 520                              DATA_BLOB *out)
 521 {
 522         DATA_BLOB sig;
 523         NTSTATUS nt_status;
 524
 525         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 526
 527                 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
 528                 if (!out->data) {
 529                         return NT_STATUS_NO_MEMORY;
 530                 }
 531                 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
 532
 533                 nt_status = gensec_ntlmssp_seal_packet(gensec_security, sig_mem_ctx,
 534                                                        out->data + NTLMSSP_SIG_SIZE,
 535                                                        out->length - NTLMSSP_SIG_SIZE,
 536                                                        out->data + NTLMSSP_SIG_SIZE,
 537                                                        out->length - NTLMSSP_SIG_SIZE,
 538                                                        &sig);
 539
 540                 if (NT_STATUS_IS_OK(nt_status)) {
 541                         memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
 542                 }
 543                 return nt_status;
 544
 545         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 546
 547                 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
 548                 if (!out->data) {
 549                         return NT_STATUS_NO_MEMORY;
 550                 }
 551                 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
 552
 553                 nt_status = gensec_ntlmssp_sign_packet(gensec_security, sig_mem_ctx,
 554                                                        out->data + NTLMSSP_SIG_SIZE,
 555                                                        out->length - NTLMSSP_SIG_SIZE,
 556                                                        out->data + NTLMSSP_SIG_SIZE,
 557                                                        out->length - NTLMSSP_SIG_SIZE,
 558                                                        &sig);
 559
 560                 if (NT_STATUS_IS_OK(nt_status)) {
 561                         memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
 562                 }
 563                 return nt_status;
 564
 565         } else {
 566                 *out = *in;
 567                 return NT_STATUS_OK;
 568         }
 569 }
 570
 571
 572 NTSTATUS gensec_ntlmssp_unwrap(struct gensec_security *gensec_security,
 573                                TALLOC_CTX *sig_mem_ctx,
 574                                const DATA_BLOB *in,
 575                                DATA_BLOB *out)
 576 {
 577         struct gensec_ntlmssp_context *gensec_ntlmssp =
 578                 talloc_get_type_abort(gensec_security->private_data,
 579                                       struct gensec_ntlmssp_context);
 580         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 581         DATA_BLOB sig;
 582
 583         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 584                 if (in->length < NTLMSSP_SIG_SIZE) {
 585                         return NT_STATUS_INVALID_PARAMETER;
 586                 }
 587                 sig.data = in->data;
 588                 sig.length = NTLMSSP_SIG_SIZE;
 589
 590                 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
 591
 592                 return gensec_ntlmssp_unseal_packet(gensec_security, sig_mem_ctx,
 593                                                     out->data, out->length,
 594                                                     out->data, out->length,
 595                                                     &sig);
 596
 597         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 598                 NTSTATUS status;
 599                 uint32_t ntlm_seqnum;
 600                 struct arcfour_state ntlm_state;
 601                 uint32_t ntlm2_seqnum_r;
 602                 uint8_t ntlm2_key_r[16];
 603                 struct arcfour_state ntlm2_state_r;
 604
 605                 if (in->length < NTLMSSP_SIG_SIZE) {
 606                         return NT_STATUS_INVALID_PARAMETER;
 607                 }
 608                 sig.data = in->data;
 609                 sig.length = NTLMSSP_SIG_SIZE;
 610                 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
 611
 612                 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 613                         ntlm2_seqnum_r = gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num;
 614                         ntlm2_state_r = *gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state;
 615                         memcpy(ntlm2_key_r,
 616                                gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
 617                                16);
 618                 } else {
 619                         ntlm_seqnum = gensec_ntlmssp_state->crypt.ntlm.seq_num;
 620                         ntlm_state = *gensec_ntlmssp_state->crypt.ntlm.arcfour_state;
 621                 }
 622
 623                 status = gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx,
 624                                                      out->data, out->length,
 625                                                      out->data, out->length,
 626                                                      &sig);
 627                 if (!NT_STATUS_IS_OK(status)) {
 628                         NTSTATUS check_status = status;
 629                         /*
 630                          * The Windows LDAP libraries seems to have a bug
 631                          * and always use sealing even if only signing was
 632                          * negotiated. So we need to fallback.
 633                          */
 634
 635                         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 636                                 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = ntlm2_seqnum_r;
 637                                 *gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = ntlm2_state_r;
 638                                 memcpy(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
 639                                        ntlm2_key_r, 16);
 640                         } else {
 641                                 gensec_ntlmssp_state->crypt.ntlm.seq_num = ntlm_seqnum;
 642                                 *gensec_ntlmssp_state->crypt.ntlm.arcfour_state = ntlm_state;
 643                         }
 644
 645                         status = gensec_ntlmssp_unseal_packet(gensec_security,
 646                                                               sig_mem_ctx,
 647                                                               out->data,
 648                                                               out->length,
 649                                                               out->data,
 650                                                               out->length,
 651                                                               &sig);
 652                         if (NT_STATUS_IS_OK(status)) {
 653                                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 654                         } else {
 655                                 status = check_status;
 656                         }
 657                 }
 658
 659                 if (!NT_STATUS_IS_OK(status)) {
 660                         DEBUG(1, ("NTLMSSP packet check for unwrap failed due to invalid signature\n"));
 661                 }
 662                 return status;
 663         } else {
 664                 *out = *in;
 665                 return NT_STATUS_OK;
 666         }
 667 }
 668