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 /* TODO: make this non-public */
 133 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 = (struct 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 = (struct 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         nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
 169                                                   data, length,
 170                                                   whole_pdu, pdu_length,
 171                                                   NTLMSSP_RECEIVE, &local_sig, true);
 172
 173         if (!NT_STATUS_IS_OK(nt_status)) {
 174                 DEBUG(0, ("NTLMSSP packet check failed with %s\n", nt_errstr(nt_status)));
 175                 return nt_status;
 176         }
 177
 178         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 179                 if (local_sig.length != sig->length ||
 180                     memcmp(local_sig.data,
 181                            sig->data, sig->length) != 0) {
 182                         DEBUG(5, ("BAD SIG NTLM2: wanted signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
 183                         dump_data(5, local_sig.data, local_sig.length);
 184
 185                         DEBUG(5, ("BAD SIG: got signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
 186                         dump_data(5, sig->data, sig->length);
 187
 188                         DEBUG(1, ("NTLMSSP NTLM2 packet check failed due to invalid signature on %llu bytes of input!\n", (unsigned long long)pdu_length));
 189                         return NT_STATUS_ACCESS_DENIED;
 190                 }
 191         } else {
 192                 if (local_sig.length != sig->length ||
 193                     memcmp(local_sig.data + 8,
 194                            sig->data + 8, sig->length - 8) != 0) {
 195                         DEBUG(5, ("BAD SIG NTLM1: wanted signature of %llu bytes of input:\n", (unsigned long long)length));
 196                         dump_data(5, local_sig.data, local_sig.length);
 197
 198                         DEBUG(5, ("BAD SIG: got signature of %llu bytes of input:\n", (unsigned long long)length));
 199                         dump_data(5, sig->data, sig->length);
 200
 201                         DEBUG(1, ("NTLMSSP NTLM1 packet check failed due to invalid signature on %llu bytes of input:\n", (unsigned long long)length));
 202                         return NT_STATUS_ACCESS_DENIED;
 203                 }
 204         }
 205         dump_data_pw("checked ntlmssp signature\n", sig->data, sig->length);
 206
 207         return NT_STATUS_OK;
 208 }
 209
 210
 211 /**
 212  * Seal data with the NTLMSSP algorithm
 213  *
 214  */
 215
 216 NTSTATUS gensec_ntlmssp_seal_packet(struct gensec_security *gensec_security,
 217                                     TALLOC_CTX *sig_mem_ctx,
 218                                     uint8_t *data, size_t length,
 219                                     const uint8_t *whole_pdu, size_t pdu_length,
 220                                     DATA_BLOB *sig)
 221 {
 222         struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
 223         NTSTATUS nt_status;
 224         if (!gensec_ntlmssp_state->session_key.length) {
 225                 DEBUG(3, ("NO session key, cannot seal packet\n"));
 226                 return NT_STATUS_NO_USER_SESSION_KEY;
 227         }
 228
 229         DEBUG(10,("ntlmssp_seal_data: seal\n"));
 230         dump_data_pw("ntlmssp clear data\n", data, length);
 231         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 232                 /* The order of these two operations matters - we must first seal the packet,
 233                    then seal the sequence number - this is becouse the send_seal_hash is not
 234                    constant, but is is rather updated with each iteration */
 235                 nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
 236                                                           data, length,
 237                                                           whole_pdu, pdu_length,
 238                                                           NTLMSSP_SEND, sig, false);
 239                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, data, length);
 240                 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 241                         arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, sig->data+4, 8);
 242                 }
 243         } else {
 244                 uint32_t crc;
 245                 crc = crc32_calc_buffer(data, length);
 246                 if (!msrpc_gen(sig_mem_ctx,
 247                                sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
 248                         return NT_STATUS_NO_MEMORY;
 249                 }
 250
 251                 /* The order of these two operations matters - we must
 252                    first seal the packet, then seal the sequence
 253                    number - this is becouse the ntlmssp_hash is not
 254                    constant, but is is rather updated with each
 255                    iteration */
 256
 257                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
 258                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
 259                 /* increment counter on send */
 260                 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
 261                 nt_status = NT_STATUS_OK;
 262         }
 263         dump_data_pw("ntlmssp signature\n", sig->data, sig->length);
 264         dump_data_pw("ntlmssp sealed data\n", data, length);
 265
 266
 267         return nt_status;
 268 }
 269
 270 /**
 271  * Unseal data with the NTLMSSP algorithm
 272  *
 273  */
 274
 275 /*
 276   wrappers for the ntlmssp_*() functions
 277 */
 278 NTSTATUS gensec_ntlmssp_unseal_packet(struct gensec_security *gensec_security,
 279                                       TALLOC_CTX *sig_mem_ctx,
 280                                       uint8_t *data, size_t length,
 281                                       const uint8_t *whole_pdu, size_t pdu_length,
 282                                       const DATA_BLOB *sig)
 283 {
 284         struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
 285         if (!gensec_ntlmssp_state->session_key.length) {
 286                 DEBUG(3, ("NO session key, cannot unseal packet\n"));
 287                 return NT_STATUS_NO_USER_SESSION_KEY;
 288         }
 289
 290         dump_data_pw("ntlmssp sealed data\n", data, length);
 291         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 292                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, data, length);
 293         } else {
 294                 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
 295         }
 296         dump_data_pw("ntlmssp clear data\n", data, length);
 297         return gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx, data, length, whole_pdu, pdu_length, sig);
 298 }
 299
 300 /**
 301    Initialise the state for NTLMSSP signing.
 302 */
 303 /* TODO: make this non-public */
 304 NTSTATUS ntlmssp_sign_init(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 305 {
 306         TALLOC_CTX *mem_ctx = talloc_new(gensec_ntlmssp_state);
 307
 308         if (!mem_ctx) {
 309                 return NT_STATUS_NO_MEMORY;
 310         }
 311
 312         DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
 313         debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
 314
 315         if (gensec_ntlmssp_state->session_key.length < 8) {
 316                 talloc_free(mem_ctx);
 317                 DEBUG(3, ("NO session key, cannot intialise signing\n"));
 318                 return NT_STATUS_NO_USER_SESSION_KEY;
 319         }
 320
 321         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
 322         {
 323                 DATA_BLOB weak_session_key = gensec_ntlmssp_state->session_key;
 324                 const char *send_sign_const;
 325                 const char *send_seal_const;
 326                 const char *recv_sign_const;
 327                 const char *recv_seal_const;
 328
 329                 DATA_BLOB send_seal_key;
 330                 DATA_BLOB recv_seal_key;
 331
 332                 switch (gensec_ntlmssp_state->role) {
 333                 case NTLMSSP_CLIENT:
 334                         send_sign_const = CLI_SIGN;
 335                         send_seal_const = CLI_SEAL;
 336                         recv_sign_const = SRV_SIGN;
 337                         recv_seal_const = SRV_SEAL;
 338                         break;
 339                 case NTLMSSP_SERVER:
 340                         send_sign_const = SRV_SIGN;
 341                         send_seal_const = SRV_SEAL;
 342                         recv_sign_const = CLI_SIGN;
 343                         recv_seal_const = CLI_SEAL;
 344                         break;
 345                 default:
 346                         talloc_free(mem_ctx);
 347                         return NT_STATUS_INTERNAL_ERROR;
 348                 }
 349
 350                 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 351                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
 352                 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 353                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
 354
 355                 /**
 356                    Weaken NTLMSSP keys to cope with down-level
 357                    clients, servers and export restrictions.
 358
 359                    We probably should have some parameters to control
 360                    this, once we get NTLM2 working.
 361                 */
 362
 363                 /* Key weakening was not performed on the master key
 364                  * for NTLM2 (in ntlmssp_weaken_keys()), but must be
 365                  * done on the encryption subkeys only.  That is why
 366                  * we don't have this code for the ntlmv1 case.
 367                  */
 368
 369                 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
 370
 371                 } else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
 372                         weak_session_key.length = 7;
 373                 } else { /* forty bits */
 374                         weak_session_key.length = 5;
 375                 }
 376                 dump_data_pw("NTLMSSP weakend master key:\n",
 377                              weak_session_key.data,
 378                              weak_session_key.length);
 379
 380                 /* SEND: sign key */
 381                 calc_ntlmv2_key(gensec_ntlmssp_state,
 382                                 &gensec_ntlmssp_state->crypt.ntlm2.send_sign_key,
 383                                 gensec_ntlmssp_state->session_key, send_sign_const);
 384                 dump_data_pw("NTLMSSP send sign key:\n",
 385                              gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
 386                              gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length);
 387
 388                 /* SEND: seal ARCFOUR pad */
 389                 calc_ntlmv2_key(mem_ctx,
 390                                 &send_seal_key,
 391                                 weak_session_key, send_seal_const);
 392                 dump_data_pw("NTLMSSP send seal key:\n",
 393                              send_seal_key.data,
 394                              send_seal_key.length);
 395                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state,
 396                              &send_seal_key);
 397                 dump_data_pw("NTLMSSP send sesl hash:\n",
 398                              gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox,
 399                              sizeof(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox));
 400
 401                 /* RECV: sign key */
 402                 calc_ntlmv2_key(gensec_ntlmssp_state,
 403                                 &gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key,
 404                                 gensec_ntlmssp_state->session_key, recv_sign_const);
 405                 dump_data_pw("NTLMSSP recv sign key:\n",
 406                              gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
 407                              gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length);
 408
 409                 /* RECV: seal ARCFOUR pad */
 410                 calc_ntlmv2_key(mem_ctx,
 411                                 &recv_seal_key,
 412                                 weak_session_key, recv_seal_const);
 413                 dump_data_pw("NTLMSSP recv seal key:\n",
 414                              recv_seal_key.data,
 415                              recv_seal_key.length);
 416                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state,
 417                              &recv_seal_key);
 418                 dump_data_pw("NTLMSSP receive seal hash:\n",
 419                              gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox,
 420                              sizeof(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox));
 421
 422                 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num = 0;
 423                 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = 0;
 424
 425         } else {
 426                 DATA_BLOB weak_session_key = ntlmssp_weakend_key(gensec_ntlmssp_state, mem_ctx);
 427                 DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));
 428
 429                 gensec_ntlmssp_state->crypt.ntlm.arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
 430                 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm.arcfour_state);
 431
 432                 arcfour_init(gensec_ntlmssp_state->crypt.ntlm.arcfour_state,
 433                              &weak_session_key);
 434                 dump_data_pw("NTLMSSP hash:\n", gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox,
 435                              sizeof(gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox));
 436
 437                 gensec_ntlmssp_state->crypt.ntlm.seq_num = 0;
 438         }
 439
 440         talloc_free(mem_ctx);
 441         return NT_STATUS_OK;
 442 }
 443
 444 size_t gensec_ntlmssp_sig_size(struct gensec_security *gensec_security, size_t data_size)
 445 {
 446         return NTLMSSP_SIG_SIZE;
 447 }
 448
 449 NTSTATUS gensec_ntlmssp_wrap(struct gensec_security *gensec_security,
 450                              TALLOC_CTX *sig_mem_ctx,
 451                              const DATA_BLOB *in,
 452                              DATA_BLOB *out)
 453 {
 454         DATA_BLOB sig;
 455         NTSTATUS nt_status;
 456
 457         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 458
 459                 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
 460                 if (!out->data) {
 461                         return NT_STATUS_NO_MEMORY;
 462                 }
 463                 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
 464
 465                 nt_status = gensec_ntlmssp_seal_packet(gensec_security, sig_mem_ctx,
 466                                                        out->data + NTLMSSP_SIG_SIZE,
 467                                                        out->length - NTLMSSP_SIG_SIZE,
 468                                                        out->data + NTLMSSP_SIG_SIZE,
 469                                                        out->length - NTLMSSP_SIG_SIZE,
 470                                                        &sig);
 471
 472                 if (NT_STATUS_IS_OK(nt_status)) {
 473                         memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
 474                 }
 475                 return nt_status;
 476
 477         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 478
 479                 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
 480                 if (!out->data) {
 481                         return NT_STATUS_NO_MEMORY;
 482                 }
 483                 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
 484
 485                 nt_status = gensec_ntlmssp_sign_packet(gensec_security, sig_mem_ctx,
 486                                                        out->data + NTLMSSP_SIG_SIZE,
 487                                                        out->length - NTLMSSP_SIG_SIZE,
 488                                                        out->data + NTLMSSP_SIG_SIZE,
 489                                                        out->length - NTLMSSP_SIG_SIZE,
 490                                                        &sig);
 491
 492                 if (NT_STATUS_IS_OK(nt_status)) {
 493                         memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
 494                 }
 495                 return nt_status;
 496
 497         } else {
 498                 *out = *in;
 499                 return NT_STATUS_OK;
 500         }
 501 }
 502
 503
 504 NTSTATUS gensec_ntlmssp_unwrap(struct gensec_security *gensec_security,
 505                                TALLOC_CTX *sig_mem_ctx,
 506                                const DATA_BLOB *in,
 507                                DATA_BLOB *out)
 508 {
 509         DATA_BLOB sig;
 510
 511         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 512                 if (in->length < NTLMSSP_SIG_SIZE) {
 513                         return NT_STATUS_INVALID_PARAMETER;
 514                 }
 515                 sig.data = in->data;
 516                 sig.length = NTLMSSP_SIG_SIZE;
 517
 518                 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
 519
 520                 return gensec_ntlmssp_unseal_packet(gensec_security, sig_mem_ctx,
 521                                                     out->data, out->length,
 522                                                     out->data, out->length,
 523                                                     &sig);
 524
 525         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 526                 struct gensec_ntlmssp_state *gensec_ntlmssp_state =
 527                 (struct gensec_ntlmssp_state *)gensec_security->private_data;
 528                 NTSTATUS status;
 529                 uint32_t ntlm_seqnum;
 530                 struct arcfour_state ntlm_state;
 531                 uint32_t ntlm2_seqnum_r;
 532                 uint8_t ntlm2_key_r[16];
 533                 struct arcfour_state ntlm2_state_r;
 534
 535                 if (in->length < NTLMSSP_SIG_SIZE) {
 536                         return NT_STATUS_INVALID_PARAMETER;
 537                 }
 538                 sig.data = in->data;
 539                 sig.length = NTLMSSP_SIG_SIZE;
 540                 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
 541
 542                 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 543                         ntlm2_seqnum_r = gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num;
 544                         ntlm2_state_r = *gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state;
 545                         memcpy(ntlm2_key_r,
 546                                gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
 547                                16);
 548                 } else {
 549                         ntlm_seqnum = gensec_ntlmssp_state->crypt.ntlm.seq_num;
 550                         ntlm_state = *gensec_ntlmssp_state->crypt.ntlm.arcfour_state;
 551                 }
 552
 553                 status = gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx,
 554                                                      out->data, out->length,
 555                                                      out->data, out->length,
 556                                                      &sig);
 557                 if (!NT_STATUS_IS_OK(status)) {
 558                         NTSTATUS check_status = status;
 559                         /*
 560                          * The Windows LDAP libraries seems to have a bug
 561                          * and always use sealing even if only signing was
 562                          * negotiated. So we need to fallback.
 563                          */
 564
 565                         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 566                                 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = ntlm2_seqnum_r;
 567                                 *gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = ntlm2_state_r;
 568                                 memcpy(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
 569                                        ntlm2_key_r, 16);
 570                         } else {
 571                                 gensec_ntlmssp_state->crypt.ntlm.seq_num = ntlm_seqnum;
 572                                 *gensec_ntlmssp_state->crypt.ntlm.arcfour_state = ntlm_state;
 573                         }
 574
 575                         status = gensec_ntlmssp_unseal_packet(gensec_security,
 576                                                               sig_mem_ctx,
 577                                                               out->data,
 578                                                               out->length,
 579                                                               out->data,
 580                                                               out->length,
 581                                                               &sig);
 582                         if (NT_STATUS_IS_OK(status)) {
 583                                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 584                         } else {
 585                                 status = check_status;
 586                         }
 587                 }
 588                 return status;
 589         } else {
 590                 *out = *in;
 591                 return NT_STATUS_OK;
 592         }
 593 }
 594