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 2 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, write to the Free Software Foundation,
  20  *  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22
  23 #include "includes.h"
  24 #include "auth/auth.h"
  25 #include "auth/ntlmssp/ntlmssp.h"
  26 #include "auth/ntlmssp/msrpc_parse.h"
  27 #include "lib/crypto/crypto.h"
  28
  29 #define CLI_SIGN "session key to client-to-server signing key magic constant"
  30 #define CLI_SEAL "session key to client-to-server sealing key magic constant"
  31 #define SRV_SIGN "session key to server-to-client signing key magic constant"
  32 #define SRV_SEAL "session key to server-to-client sealing key magic constant"
  33
  34 /**
  35  * Some notes on the NTLM2 code:
  36  *
  37  * NTLM2 is a AEAD system.  This means that the data encrypted is not
  38  * all the data that is signed.  In DCE-RPC case, the headers of the
  39  * DCE-RPC packets are also signed.  This prevents some of the
  40  * fun-and-games one might have by changing them.
  41  *
  42  */
  43
  44 static void calc_ntlmv2_key(TALLOC_CTX *mem_ctx,
  45                             DATA_BLOB *subkey,
  46                             DATA_BLOB session_key,
  47                             const char *constant)
  48 {
  49         struct MD5Context ctx3;
  50         *subkey = data_blob_talloc(mem_ctx, NULL, 16);
  51         MD5Init(&ctx3);
  52         MD5Update(&ctx3, session_key.data, session_key.length);
  53         MD5Update(&ctx3, (const uint8_t *)constant, strlen(constant)+1);
  54         MD5Final(subkey->data, &ctx3);
  55 }
  56
  57 enum ntlmssp_direction {
  58         NTLMSSP_SEND,
  59         NTLMSSP_RECEIVE
  60 };
  61
  62 static NTSTATUS ntlmssp_make_packet_signature(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
  63                                               TALLOC_CTX *sig_mem_ctx,
  64                                               const uint8_t *data, size_t length,
  65                                               const uint8_t *whole_pdu, size_t pdu_length,
  66                                               enum ntlmssp_direction direction,
  67                                               DATA_BLOB *sig, BOOL encrypt_sig)
  68 {
  69         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
  70
  71                 HMACMD5Context ctx;
  72                 uint8_t digest[16];
  73                 uint8_t seq_num[4];
  74
  75                 *sig = data_blob_talloc(sig_mem_ctx, NULL, NTLMSSP_SIG_SIZE);
  76                 if (!sig->data) {
  77                         return NT_STATUS_NO_MEMORY;
  78                 }
  79
  80                 switch (direction) {
  81                 case NTLMSSP_SEND:
  82                         SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.send_seq_num);
  83                         gensec_ntlmssp_state->crypt.ntlm2.send_seq_num++;
  84                         hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
  85                                                  gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length, &ctx);
  86                         break;
  87                 case NTLMSSP_RECEIVE:
  88                         SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num);
  89                         gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num++;
  90                         hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
  91                                                  gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length, &ctx);
  92                         break;
  93                 }
  94                 hmac_md5_update(seq_num, sizeof(seq_num), &ctx);
  95                 hmac_md5_update(whole_pdu, pdu_length, &ctx);
  96                 hmac_md5_final(digest, &ctx);
  97
  98                 if (encrypt_sig && gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
  99                         switch (direction) {
 100                         case NTLMSSP_SEND:
 101                                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, digest, 8);
 102                                 break;
 103                         case NTLMSSP_RECEIVE:
 104                                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, digest, 8);
 105                                 break;
 106                         }
 107                 }
 108
 109                 SIVAL(sig->data, 0, NTLMSSP_SIGN_VERSION);
 110                 memcpy(sig->data + 4, digest, 8);
 111                 memcpy(sig->data + 12, seq_num, 4);
 112
 113                 DEBUG(10, ("NTLM2: created signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
 114                 dump_data(11, sig->data, sig->length);
 115
 116         } else {
 117                 uint32_t crc;
 118                 crc = crc32_calc_buffer(data, length);
 119                 if (!msrpc_gen(sig_mem_ctx, 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 /* TODO: make this non-public */
 133 _PUBLIC_ NTSTATUS gensec_ntlmssp_sign_packet(struct gensec_security *gensec_security,
 134                                     TALLOC_CTX *sig_mem_ctx,
 135                                     const uint8_t *data, size_t length,
 136                                     const uint8_t *whole_pdu, size_t pdu_length,
 137                                     DATA_BLOB *sig)
 138 {
 139         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 140
 141         return ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
 142                                              data, length,
 143                                              whole_pdu, pdu_length,
 144                                              NTLMSSP_SEND, sig, True);
 145 }
 146
 147 /**
 148  * Check the signature of an incoming packet
 149  *
 150  */
 151
 152 NTSTATUS gensec_ntlmssp_check_packet(struct gensec_security *gensec_security,
 153                                      TALLOC_CTX *sig_mem_ctx,
 154                                      const uint8_t *data, size_t length,
 155                                      const uint8_t *whole_pdu, size_t pdu_length,
 156                                      const DATA_BLOB *sig)
 157 {
 158         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 159
 160         DATA_BLOB local_sig;
 161         NTSTATUS nt_status;
 162
 163         if (!gensec_ntlmssp_state->session_key.length) {
 164                 DEBUG(3, ("NO session key, cannot check packet signature\n"));
 165                 return NT_STATUS_NO_USER_SESSION_KEY;
 166         }
 167
 168         if (sig->length < 8) {
 169                 DEBUG(0, ("NTLMSSP packet check failed due to short signature (%lu bytes)!\n",
 170                           (unsigned long)sig->length));
 171         }
 172
 173         nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
 174                                                   data, length,
 175                                                   whole_pdu, pdu_length,
 176                                                   NTLMSSP_RECEIVE, &local_sig, True);
 177
 178         if (!NT_STATUS_IS_OK(nt_status)) {
 179                 DEBUG(0, ("NTLMSSP packet check failed with %s\n", nt_errstr(nt_status)));
 180                 return nt_status;
 181         }
 182
 183         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 184                 if (local_sig.length != sig->length ||
 185                     memcmp(local_sig.data,
 186                            sig->data, sig->length) != 0) {
 187                         DEBUG(5, ("BAD SIG NTLM2: wanted signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
 188                         dump_data(5, local_sig.data, local_sig.length);
 189
 190                         DEBUG(5, ("BAD SIG: got signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
 191                         dump_data(5, sig->data, sig->length);
 192
 193                         DEBUG(0, ("NTLMSSP NTLM2 packet check failed due to invalid signature on %llu bytes of input!\n", (unsigned long long)pdu_length));
 194                         return NT_STATUS_ACCESS_DENIED;
 195                 }
 196         } else {
 197                 if (local_sig.length != sig->length ||
 198                     memcmp(local_sig.data + 8,
 199                            sig->data + 8, sig->length - 8) != 0) {
 200                         DEBUG(5, ("BAD SIG NTLM1: wanted signature of %llu bytes of input:\n", (unsigned long long)length));
 201                         dump_data(5, local_sig.data, local_sig.length);
 202
 203                         DEBUG(5, ("BAD SIG: got signature of %llu bytes of input:\n", (unsigned long long)length));
 204                         dump_data(5, sig->data, sig->length);
 205
 206                         DEBUG(0, ("NTLMSSP NTLM1 packet check failed due to invalid signature on %llu bytes of input:\n", (unsigned long long)length));
 207                         return NT_STATUS_ACCESS_DENIED;
 208                 }
 209         }
 210         dump_data_pw("checked ntlmssp signature\n", sig->data, sig->length);
 211
 212         return NT_STATUS_OK;
 213 }
 214
 215
 216 /**
 217  * Seal data with the NTLMSSP algorithm
 218  *
 219  */
 220
 221 NTSTATUS gensec_ntlmssp_seal_packet(struct gensec_security *gensec_security,
 222                                     TALLOC_CTX *sig_mem_ctx,
 223                                     uint8_t *data, size_t length,
 224                                     const uint8_t *whole_pdu, size_t pdu_length,
 225                                     DATA_BLOB *sig)
 226 {
 227         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 228         NTSTATUS nt_status;
 229         if (!gensec_ntlmssp_state->session_key.length) {
 230                 DEBUG(3, ("NO session key, cannot seal packet\n"));
 231                 return NT_STATUS_NO_USER_SESSION_KEY;
 232         }
 233
 234         DEBUG(10,("ntlmssp_seal_data: seal\n"));
 235         dump_data_pw("ntlmssp clear data\n", data, length);
 236         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 237                 /* The order of these two operations matters - we must first seal the packet,
 238                    then seal the sequence number - this is becouse the send_seal_hash is not
 239                    constant, but is is rather updated with each iteration */
 240                 nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
 241                                                           data, length,
 242                                                           whole_pdu, pdu_length,
 243                                                           NTLMSSP_SEND, sig, False);
 244                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, data, length);
 245                 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 246                         arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, sig->data+4, 8);
 247                 }
 248         } else {
 249                 uint32_t crc;
 250                 crc = crc32_calc_buffer(data, length);
 251                 if (!msrpc_gen(sig_mem_ctx, sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
 252                         return NT_STATUS_NO_MEMORY;
 253                 }
 254
 255                 /* The order of these two operations matters - we must
 256                    first seal the packet, then seal the sequence
 257                    number - this is becouse the ntlmssp_hash is not
 258                    constant, but is is rather updated with each
 259                    iteration */
 260
 261                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
 262                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
 263                 /* increment counter on send */
 264                 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
 265                 nt_status = NT_STATUS_OK;
 266         }
 267         dump_data_pw("ntlmssp signature\n", sig->data, sig->length);
 268         dump_data_pw("ntlmssp sealed data\n", data, length);
 269
 270
 271         return nt_status;
 272 }
 273
 274 /**
 275  * Unseal data with the NTLMSSP algorithm
 276  *
 277  */
 278
 279 /*
 280   wrappers for the ntlmssp_*() functions
 281 */
 282 NTSTATUS gensec_ntlmssp_unseal_packet(struct gensec_security *gensec_security,
 283                                       TALLOC_CTX *sig_mem_ctx,
 284                                       uint8_t *data, size_t length,
 285                                       const uint8_t *whole_pdu, size_t pdu_length,
 286                                       const DATA_BLOB *sig)
 287 {
 288         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 289         if (!gensec_ntlmssp_state->session_key.length) {
 290                 DEBUG(3, ("NO session key, cannot unseal packet\n"));
 291                 return NT_STATUS_NO_USER_SESSION_KEY;
 292         }
 293
 294         dump_data_pw("ntlmssp sealed data\n", data, length);
 295         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 296                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, data, length);
 297         } else {
 298                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
 299         }
 300         dump_data_pw("ntlmssp clear data\n", data, length);
 301         return gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx, data, length, whole_pdu, pdu_length, sig);
 302 }
 303
 304 /**
 305    Initialise the state for NTLMSSP signing.
 306 */
 307 /* TODO: make this non-public */
 308 _PUBLIC_ NTSTATUS ntlmssp_sign_init(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 309 {
 310         TALLOC_CTX *mem_ctx = talloc_new(gensec_ntlmssp_state);
 311
 312         if (!mem_ctx) {
 313                 return NT_STATUS_NO_MEMORY;
 314         }
 315
 316         DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
 317         debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
 318
 319         if (gensec_ntlmssp_state->session_key.length < 8) {
 320                 talloc_free(mem_ctx);
 321                 DEBUG(3, ("NO session key, cannot intialise signing\n"));
 322                 return NT_STATUS_NO_USER_SESSION_KEY;
 323         }
 324
 325         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
 326         {
 327                 DATA_BLOB weak_session_key = gensec_ntlmssp_state->session_key;
 328                 const char *send_sign_const;
 329                 const char *send_seal_const;
 330                 const char *recv_sign_const;
 331                 const char *recv_seal_const;
 332
 333                 DATA_BLOB send_seal_key;
 334                 DATA_BLOB recv_seal_key;
 335
 336                 switch (gensec_ntlmssp_state->role) {
 337                 case NTLMSSP_CLIENT:
 338                         send_sign_const = CLI_SIGN;
 339                         send_seal_const = CLI_SEAL;
 340                         recv_sign_const = SRV_SIGN;
 341                         recv_seal_const = SRV_SEAL;
 342                         break;
 343                 case NTLMSSP_SERVER:
 344                         send_sign_const = SRV_SIGN;
 345                         send_seal_const = SRV_SEAL;
 346                         recv_sign_const = CLI_SIGN;
 347                         recv_seal_const = CLI_SEAL;
 348                         break;
 349                 default:
 350                         talloc_free(mem_ctx);
 351                         return NT_STATUS_INTERNAL_ERROR;
 352                 }
 353
 354                 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 355                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
 356                 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 357                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
 358
 359                 /**
 360                    Weaken NTLMSSP keys to cope with down-level
 361                    clients, servers and export restrictions.
 362
 363                    We probably should have some parameters to control
 364                    this, once we get NTLM2 working.
 365                 */
 366
 367                 /* Key weakening was not performed on the master key
 368                  * for NTLM2 (in ntlmssp_weaken_keys()), but must be
 369                  * done on the encryption subkeys only.  That is why
 370                  * we don't have this code for the ntlmv1 case.
 371                  */
 372
 373                 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
 374
 375                 } else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
 376                         weak_session_key.length = 7;
 377                 } else { /* forty bits */
 378                         weak_session_key.length = 5;
 379                 }
 380                 dump_data_pw("NTLMSSP weakend master key:\n",
 381                              weak_session_key.data,
 382                              weak_session_key.length);
 383
 384                 /* SEND: sign key */
 385                 calc_ntlmv2_key(gensec_ntlmssp_state,
 386                                 &gensec_ntlmssp_state->crypt.ntlm2.send_sign_key,
 387                                 gensec_ntlmssp_state->session_key, send_sign_const);
 388                 dump_data_pw("NTLMSSP send sign key:\n",
 389                              gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
 390                              gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length);
 391
 392                 /* SEND: seal ARCFOUR pad */
 393                 calc_ntlmv2_key(mem_ctx,
 394                                 &send_seal_key,
 395                                 weak_session_key, send_seal_const);
 396                 dump_data_pw("NTLMSSP send seal key:\n",
 397                              send_seal_key.data,
 398                              send_seal_key.length);
 399                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state,
 400                              &send_seal_key);
 401                 dump_data_pw("NTLMSSP send sesl hash:\n",
 402                              gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox,
 403                              sizeof(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox));
 404
 405                 /* RECV: sign key */
 406                 calc_ntlmv2_key(gensec_ntlmssp_state,
 407                                 &gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key,
 408                                 gensec_ntlmssp_state->session_key, recv_sign_const);
 409                 dump_data_pw("NTLMSSP recv sign key:\n",
 410                              gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
 411                              gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length);
 412
 413                 /* RECV: seal ARCFOUR pad */
 414                 calc_ntlmv2_key(mem_ctx,
 415                                 &recv_seal_key,
 416                                 weak_session_key, recv_seal_const);
 417                 dump_data_pw("NTLMSSP recv seal key:\n",
 418                              recv_seal_key.data,
 419                              recv_seal_key.length);
 420                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state,
 421                              &recv_seal_key);
 422                 dump_data_pw("NTLMSSP receive seal hash:\n",
 423                              gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox,
 424                              sizeof(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox));
 425
 426                 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num = 0;
 427                 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = 0;
 428
 429         } else {
 430                 DATA_BLOB weak_session_key = ntlmssp_weakend_key(gensec_ntlmssp_state, mem_ctx);
 431                 DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));
 432
 433                 gensec_ntlmssp_state->crypt.ntlm.arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 434                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm.arcfour_state);
 435
 436                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm.arcfour_state,
 437                              &weak_session_key);
 438                 dump_data_pw("NTLMSSP hash:\n", gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox,
 439                              sizeof(gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox));
 440
 441                 gensec_ntlmssp_state->crypt.ntlm.seq_num = 0;
 442         }
 443
 444         talloc_free(mem_ctx);
 445         return NT_STATUS_OK;
 446 }
 447
 448 size_t gensec_ntlmssp_sig_size(struct gensec_security *gensec_security, size_t data_size)
 449 {
 450         return NTLMSSP_SIG_SIZE;
 451 }
 452
 453 NTSTATUS gensec_ntlmssp_wrap(struct gensec_security *gensec_security,
 454                              TALLOC_CTX *sig_mem_ctx,
 455                              const DATA_BLOB *in,
 456                              DATA_BLOB *out)
 457 {
 458         DATA_BLOB sig;
 459         NTSTATUS nt_status;
 460
 461         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 462
 463                 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
 464                 if (!out->data) {
 465                         return NT_STATUS_NO_MEMORY;
 466                 }
 467                 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
 468
 469                 nt_status = gensec_ntlmssp_seal_packet(gensec_security, sig_mem_ctx,
 470                                                        out->data + NTLMSSP_SIG_SIZE,
 471                                                        out->length - NTLMSSP_SIG_SIZE,
 472                                                        out->data + NTLMSSP_SIG_SIZE,
 473                                                        out->length - NTLMSSP_SIG_SIZE,
 474                                                        &sig);
 475
 476                 if (NT_STATUS_IS_OK(nt_status)) {
 477                         memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
 478                 }
 479                 return nt_status;
 480
 481         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 482
 483                 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
 484                 if (!out->data) {
 485                         return NT_STATUS_NO_MEMORY;
 486                 }
 487                 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
 488
 489                 nt_status = gensec_ntlmssp_sign_packet(gensec_security, sig_mem_ctx,
 490                                                        out->data + NTLMSSP_SIG_SIZE,
 491                                                        out->length - NTLMSSP_SIG_SIZE,
 492                                                        out->data + NTLMSSP_SIG_SIZE,
 493                                                        out->length - NTLMSSP_SIG_SIZE,
 494                                                        &sig);
 495
 496                 if (NT_STATUS_IS_OK(nt_status)) {
 497                         memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
 498                 }
 499                 return nt_status;
 500
 501         } else {
 502                 *out = *in;
 503                 return NT_STATUS_OK;
 504         }
 505 }
 506
 507
 508 NTSTATUS gensec_ntlmssp_unwrap(struct gensec_security *gensec_security,
 509                                TALLOC_CTX *sig_mem_ctx,
 510                                const DATA_BLOB *in,
 511                                DATA_BLOB *out)
 512 {
 513         DATA_BLOB sig;
 514
 515         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 516                 if (in->length < NTLMSSP_SIG_SIZE) {
 517                         return NT_STATUS_INVALID_PARAMETER;
 518                 }
 519                 sig.data = in->data;
 520                 sig.length = NTLMSSP_SIG_SIZE;
 521
 522                 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
 523
 524                 return gensec_ntlmssp_unseal_packet(gensec_security, sig_mem_ctx,
 525                                                     out->data, out->length,
 526                                                     out->data, out->length,
 527                                                     &sig);
 528
 529         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 530                 if (in->length < NTLMSSP_SIG_SIZE) {
 531                         return NT_STATUS_INVALID_PARAMETER;
 532                 }
 533                 sig.data = in->data;
 534                 sig.length = NTLMSSP_SIG_SIZE;
 535
 536                 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
 537
 538                 return gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx,
 539                                                    out->data, out->length,
 540                                                    out->data, out->length,
 541                                                    &sig);
 542         } else {
 543                 *out = *in;
 544                 return NT_STATUS_OK;
 545         }
 546 }
 547