auth/gensec/schannel.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    dcerpc schannel operations
   5
   6    Copyright (C) Andrew Tridgell 2004
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "librpc/gen_ndr/ndr_schannel.h"
  25 #include "auth/auth.h"
  26 #include "auth/credentials/credentials.h"
  27 #include "auth/gensec/gensec.h"
  28 #include "auth/gensec/gensec_internal.h"
  29 #include "auth/gensec/gensec_proto.h"
  30 #include "../libcli/auth/schannel.h"
  31 #include "librpc/gen_ndr/dcerpc.h"
  32 #include "param/param.h"
  33 #include "auth/gensec/gensec_toplevel_proto.h"
  34 #include "lib/crypto/crypto.h"
  35
  36 struct schannel_state {
  37         uint64_t seq_num;
  38         bool initiator;
  39         struct netlogon_creds_CredentialState *creds;
  40 };
  41
  42 #define SETUP_SEQNUM(state, buf, initiator) do { \
  43         uint8_t *_buf = buf; \
  44         uint32_t _seq_num_low = (state)->seq_num & UINT32_MAX; \
  45         uint32_t _seq_num_high = (state)->seq_num >> 32; \
  46         if (initiator) { \
  47                 _seq_num_high |= 0x80000000; \
  48         } \
  49         RSIVAL(_buf, 0, _seq_num_low); \
  50         RSIVAL(_buf, 4, _seq_num_high); \
  51 } while(0)
  52
  53 static struct schannel_state *netsec_create_state(TALLOC_CTX *mem_ctx,
  54                                 struct netlogon_creds_CredentialState *creds,
  55                                 bool initiator)
  56 {
  57         struct schannel_state *state;
  58
  59         state = talloc(mem_ctx, struct schannel_state);
  60         if (state == NULL) {
  61                 return NULL;
  62         }
  63
  64         state->initiator = initiator;
  65         state->seq_num = 0;
  66         state->creds = netlogon_creds_copy(state, creds);
  67         if (state->creds == NULL) {
  68                 talloc_free(state);
  69                 return NULL;
  70         }
  71
  72         return state;
  73 }
  74
  75 static void netsec_offset_and_sizes(struct schannel_state *state,
  76                                     bool do_seal,
  77                                     uint32_t *_min_sig_size,
  78                                     uint32_t *_used_sig_size,
  79                                     uint32_t *_checksum_length,
  80                                     uint32_t *_confounder_ofs)
  81 {
  82         uint32_t min_sig_size;
  83         uint32_t used_sig_size;
  84         uint32_t checksum_length;
  85         uint32_t confounder_ofs;
  86
  87         if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
  88                 min_sig_size = 48;
  89                 used_sig_size = 56;
  90                 /*
  91                  * Note: windows has a bug here and uses the old values...
  92                  *
  93                  * checksum_length = 32;
  94                  * confounder_ofs = 48;
  95                  */
  96                 checksum_length = 8;
  97                 confounder_ofs = 24;
  98         } else {
  99                 min_sig_size = 24;
 100                 used_sig_size = 32;
 101                 checksum_length = 8;
 102                 confounder_ofs = 24;
 103         }
 104
 105         if (do_seal) {
 106                 min_sig_size += 8;
 107         }
 108
 109         if (_min_sig_size) {
 110                 *_min_sig_size = min_sig_size;
 111         }
 112
 113         if (_used_sig_size) {
 114                 *_used_sig_size = used_sig_size;
 115         }
 116
 117         if (_checksum_length) {
 118                 *_checksum_length = checksum_length;
 119         }
 120
 121         if (_confounder_ofs) {
 122                 *_confounder_ofs = confounder_ofs;
 123         }
 124 }
 125
 126 /*******************************************************************
 127  Encode or Decode the sequence number (which is symmetric)
 128  ********************************************************************/
 129 static void netsec_do_seq_num(struct schannel_state *state,
 130                               const uint8_t *checksum,
 131                               uint32_t checksum_length,
 132                               uint8_t seq_num[8])
 133 {
 134         if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
 135                 AES_KEY key;
 136                 uint8_t iv[AES_BLOCK_SIZE];
 137
 138                 AES_set_encrypt_key(state->creds->session_key, 128, &key);
 139                 ZERO_STRUCT(iv);
 140                 memcpy(iv+0, checksum, 8);
 141                 memcpy(iv+8, checksum, 8);
 142
 143                 aes_cfb8_encrypt(seq_num, seq_num, 8, &key, iv, AES_ENCRYPT);
 144         } else {
 145                 static const uint8_t zeros[4];
 146                 uint8_t sequence_key[16];
 147                 uint8_t digest1[16];
 148
 149                 hmac_md5(state->creds->session_key, zeros, sizeof(zeros), digest1);
 150                 hmac_md5(digest1, checksum, checksum_length, sequence_key);
 151                 arcfour_crypt(seq_num, sequence_key, 8);
 152         }
 153
 154         state->seq_num++;
 155 }
 156
 157 static void netsec_do_seal(struct schannel_state *state,
 158                            const uint8_t seq_num[8],
 159                            uint8_t confounder[8],
 160                            uint8_t *data, uint32_t length,
 161                            bool forward)
 162 {
 163         if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
 164                 AES_KEY key;
 165                 uint8_t iv[AES_BLOCK_SIZE];
 166                 uint8_t sess_kf0[16];
 167                 int i;
 168
 169                 for (i = 0; i < 16; i++) {
 170                         sess_kf0[i] = state->creds->session_key[i] ^ 0xf0;
 171                 }
 172
 173                 AES_set_encrypt_key(sess_kf0, 128, &key);
 174                 ZERO_STRUCT(iv);
 175                 memcpy(iv+0, seq_num, 8);
 176                 memcpy(iv+8, seq_num, 8);
 177
 178                 if (forward) {
 179                         aes_cfb8_encrypt(confounder, confounder, 8, &key, iv, AES_ENCRYPT);
 180                         aes_cfb8_encrypt(data, data, length, &key, iv, AES_ENCRYPT);
 181                 } else {
 182                         aes_cfb8_encrypt(confounder, confounder, 8, &key, iv, AES_DECRYPT);
 183                         aes_cfb8_encrypt(data, data, length, &key, iv, AES_DECRYPT);
 184                 }
 185         } else {
 186                 uint8_t sealing_key[16];
 187                 static const uint8_t zeros[4];
 188                 uint8_t digest2[16];
 189                 uint8_t sess_kf0[16];
 190                 int i;
 191
 192                 for (i = 0; i < 16; i++) {
 193                         sess_kf0[i] = state->creds->session_key[i] ^ 0xf0;
 194                 }
 195
 196                 hmac_md5(sess_kf0, zeros, 4, digest2);
 197                 hmac_md5(digest2, seq_num, 8, sealing_key);
 198
 199                 arcfour_crypt(confounder, sealing_key, 8);
 200                 arcfour_crypt(data, sealing_key, length);
 201         }
 202 }
 203
 204 /*******************************************************************
 205  Create a digest over the entire packet (including the data), and
 206  MD5 it with the session key.
 207  ********************************************************************/
 208 static void netsec_do_sign(struct schannel_state *state,
 209                            const uint8_t *confounder,
 210                            const uint8_t *data, size_t length,
 211                            uint8_t header[8],
 212                            uint8_t *checksum)
 213 {
 214         if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
 215                 struct HMACSHA256Context ctx;
 216
 217                 hmac_sha256_init(state->creds->session_key,
 218                                  sizeof(state->creds->session_key),
 219                                  &ctx);
 220
 221                 if (confounder) {
 222                         SSVAL(header, 0, NL_SIGN_HMAC_SHA256);
 223                         SSVAL(header, 2, NL_SEAL_AES128);
 224                         SSVAL(header, 4, 0xFFFF);
 225                         SSVAL(header, 6, 0x0000);
 226
 227                         hmac_sha256_update(header, 8, &ctx);
 228                         hmac_sha256_update(confounder, 8, &ctx);
 229                 } else {
 230                         SSVAL(header, 0, NL_SIGN_HMAC_SHA256);
 231                         SSVAL(header, 2, NL_SEAL_NONE);
 232                         SSVAL(header, 4, 0xFFFF);
 233                         SSVAL(header, 6, 0x0000);
 234
 235                         hmac_sha256_update(header, 8, &ctx);
 236                 }
 237
 238                 hmac_sha256_update(data, length, &ctx);
 239
 240                 hmac_sha256_final(checksum, &ctx);
 241         } else {
 242                 uint8_t packet_digest[16];
 243                 static const uint8_t zeros[4];
 244                 MD5_CTX ctx;
 245
 246                 MD5Init(&ctx);
 247                 MD5Update(&ctx, zeros, 4);
 248                 if (confounder) {
 249                         SSVAL(header, 0, NL_SIGN_HMAC_MD5);
 250                         SSVAL(header, 2, NL_SEAL_RC4);
 251                         SSVAL(header, 4, 0xFFFF);
 252                         SSVAL(header, 6, 0x0000);
 253
 254                         MD5Update(&ctx, header, 8);
 255                         MD5Update(&ctx, confounder, 8);
 256                 } else {
 257                         SSVAL(header, 0, NL_SIGN_HMAC_MD5);
 258                         SSVAL(header, 2, NL_SEAL_NONE);
 259                         SSVAL(header, 4, 0xFFFF);
 260                         SSVAL(header, 6, 0x0000);
 261
 262                         MD5Update(&ctx, header, 8);
 263                 }
 264                 MD5Update(&ctx, data, length);
 265                 MD5Final(packet_digest, &ctx);
 266
 267                 hmac_md5(state->creds->session_key,
 268                          packet_digest, sizeof(packet_digest),
 269                          checksum);
 270         }
 271 }
 272
 273 static NTSTATUS netsec_incoming_packet(struct schannel_state *state,
 274                                 bool do_unseal,
 275                                 uint8_t *data, size_t length,
 276                                 const DATA_BLOB *sig)
 277 {
 278         uint32_t min_sig_size = 0;
 279         uint8_t header[8];
 280         uint8_t checksum[32];
 281         uint32_t checksum_length = sizeof(checksum_length);
 282         uint8_t _confounder[8];
 283         uint8_t *confounder = NULL;
 284         uint32_t confounder_ofs = 0;
 285         uint8_t seq_num[8];
 286         int ret;
 287
 288         netsec_offset_and_sizes(state,
 289                                 do_unseal,
 290                                 &min_sig_size,
 291                                 NULL,
 292                                 &checksum_length,
 293                                 &confounder_ofs);
 294
 295         if (sig->length < min_sig_size) {
 296                 return NT_STATUS_ACCESS_DENIED;
 297         }
 298
 299         if (do_unseal) {
 300                 confounder = _confounder;
 301                 memcpy(confounder, sig->data+confounder_ofs, 8);
 302         } else {
 303                 confounder = NULL;
 304         }
 305
 306         SETUP_SEQNUM(state, seq_num, !state->initiator);
 307
 308         if (do_unseal) {
 309                 netsec_do_seal(state, seq_num,
 310                                confounder,
 311                                data, length,
 312                                false);
 313         }
 314
 315         netsec_do_sign(state, confounder,
 316                        data, length,
 317                        header, checksum);
 318
 319         ret = memcmp(checksum, sig->data+16, checksum_length);
 320         if (ret != 0) {
 321                 dump_data_pw("calc digest:", checksum, checksum_length);
 322                 dump_data_pw("wire digest:", sig->data+16, checksum_length);
 323                 return NT_STATUS_ACCESS_DENIED;
 324         }
 325
 326         netsec_do_seq_num(state, checksum, checksum_length, seq_num);
 327
 328         ret = memcmp(seq_num, sig->data+8, 8);
 329         if (ret != 0) {
 330                 dump_data_pw("calc seq num:", seq_num, 8);
 331                 dump_data_pw("wire seq num:", sig->data+8, 8);
 332                 return NT_STATUS_ACCESS_DENIED;
 333         }
 334
 335         return NT_STATUS_OK;
 336 }
 337
 338 static uint32_t netsec_outgoing_sig_size(struct schannel_state *state)
 339 {
 340         uint32_t sig_size = 0;
 341
 342         netsec_offset_and_sizes(state,
 343                                 true,
 344                                 NULL,
 345                                 &sig_size,
 346                                 NULL,
 347                                 NULL);
 348
 349         return sig_size;
 350 }
 351
 352 static NTSTATUS netsec_outgoing_packet(struct schannel_state *state,
 353                                 TALLOC_CTX *mem_ctx,
 354                                 bool do_seal,
 355                                 uint8_t *data, size_t length,
 356                                 DATA_BLOB *sig)
 357 {
 358         uint32_t min_sig_size = 0;
 359         uint32_t used_sig_size = 0;
 360         uint8_t header[8];
 361         uint8_t checksum[32];
 362         uint32_t checksum_length = sizeof(checksum_length);
 363         uint8_t _confounder[8];
 364         uint8_t *confounder = NULL;
 365         uint32_t confounder_ofs = 0;
 366         uint8_t seq_num[8];
 367
 368         netsec_offset_and_sizes(state,
 369                                 do_seal,
 370                                 &min_sig_size,
 371                                 &used_sig_size,
 372                                 &checksum_length,
 373                                 &confounder_ofs);
 374
 375         SETUP_SEQNUM(state, seq_num, state->initiator);
 376
 377         if (do_seal) {
 378                 confounder = _confounder;
 379                 generate_random_buffer(confounder, 8);
 380         } else {
 381                 confounder = NULL;
 382         }
 383
 384         netsec_do_sign(state, confounder,
 385                        data, length,
 386                        header, checksum);
 387
 388         if (do_seal) {
 389                 netsec_do_seal(state, seq_num,
 390                                confounder,
 391                                data, length,
 392                                true);
 393         }
 394
 395         netsec_do_seq_num(state, checksum, checksum_length, seq_num);
 396
 397         (*sig) = data_blob_talloc_zero(mem_ctx, used_sig_size);
 398
 399         memcpy(sig->data, header, 8);
 400         memcpy(sig->data+8, seq_num, 8);
 401         memcpy(sig->data+16, checksum, checksum_length);
 402
 403         if (confounder) {
 404                 memcpy(sig->data+confounder_ofs, confounder, 8);
 405         }
 406
 407         dump_data_pw("signature:", sig->data+ 0, 8);
 408         dump_data_pw("seq_num  :", sig->data+ 8, 8);
 409         dump_data_pw("digest   :", sig->data+16, checksum_length);
 410         dump_data_pw("confound :", sig->data+confounder_ofs, 8);
 411
 412         return NT_STATUS_OK;
 413 }
 414
 415 _PUBLIC_ NTSTATUS gensec_schannel_init(void);
 416
 417 static size_t schannel_sig_size(struct gensec_security *gensec_security, size_t data_size)
 418 {
 419         struct schannel_state *state =
 420                 talloc_get_type_abort(gensec_security->private_data,
 421                 struct schannel_state);
 422
 423         return netsec_outgoing_sig_size(state);
 424 }
 425
 426 static NTSTATUS schannel_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx,
 427                                 struct tevent_context *ev,
 428                                 const DATA_BLOB in, DATA_BLOB *out)
 429 {
 430         struct schannel_state *state =
 431                 talloc_get_type(gensec_security->private_data,
 432                 struct schannel_state);
 433         NTSTATUS status;
 434         enum ndr_err_code ndr_err;
 435         struct NL_AUTH_MESSAGE bind_schannel;
 436         struct NL_AUTH_MESSAGE bind_schannel_ack;
 437         struct netlogon_creds_CredentialState *creds;
 438         const char *workstation;
 439         const char *domain;
 440
 441         *out = data_blob(NULL, 0);
 442
 443         switch (gensec_security->gensec_role) {
 444         case GENSEC_CLIENT:
 445                 if (state != NULL) {
 446                         /* we could parse the bind ack, but we don't know what it is yet */
 447                         return NT_STATUS_OK;
 448                 }
 449
 450                 creds = cli_credentials_get_netlogon_creds(gensec_security->credentials);
 451                 if (creds == NULL) {
 452                         return NT_STATUS_INVALID_PARAMETER_MIX;
 453                 }
 454
 455                 state = netsec_create_state(gensec_security,
 456                                             creds, true /* initiator */);
 457                 if (state == NULL) {
 458                         return NT_STATUS_NO_MEMORY;
 459                 }
 460                 gensec_security->private_data = state;
 461
 462                 bind_schannel.MessageType = NL_NEGOTIATE_REQUEST;
 463 #if 0
 464                 /* to support this we'd need to have access to the full domain name */
 465                 /* 0x17, 23 */
 466                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
 467                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME |
 468                                       NL_FLAG_UTF8_DNS_DOMAIN_NAME |
 469                                       NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME;
 470                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
 471                 bind_schannel.oem_netbios_computer.a = creds->computer_name;
 472                 bind_schannel.utf8_dns_domain = cli_credentials_get_realm(gensec_security->credentials);
 473                 /* w2k3 refuses us if we use the full DNS workstation?
 474                  why? perhaps because we don't fill in the dNSHostName
 475                  attribute in the machine account? */
 476                 bind_schannel.utf8_netbios_computer = creds->computer_name;
 477 #else
 478                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
 479                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME;
 480                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
 481                 bind_schannel.oem_netbios_computer.a = creds->computer_name;
 482 #endif
 483
 484                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel,
 485                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 486                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 487                         status = ndr_map_error2ntstatus(ndr_err);
 488                         DEBUG(3, ("Could not create schannel bind: %s\n",
 489                                   nt_errstr(status)));
 490                         return status;
 491                 }
 492
 493                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 494         case GENSEC_SERVER:
 495
 496                 if (state != NULL) {
 497                         /* no third leg on this protocol */
 498                         return NT_STATUS_INVALID_PARAMETER;
 499                 }
 500
 501                 /* parse the schannel startup blob */
 502                 ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel,
 503                         (ndr_pull_flags_fn_t)ndr_pull_NL_AUTH_MESSAGE);
 504                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 505                         status = ndr_map_error2ntstatus(ndr_err);
 506                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 507                                   nt_errstr(status)));
 508                         return status;
 509                 }
 510
 511                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_DOMAIN_NAME) {
 512                         domain = bind_schannel.oem_netbios_domain.a;
 513                         if (strcasecmp_m(domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)) != 0) {
 514                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 515                                           domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)));
 516                                 return NT_STATUS_LOGON_FAILURE;
 517                         }
 518                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_DNS_DOMAIN_NAME) {
 519                         domain = bind_schannel.utf8_dns_domain.u;
 520                         if (strcasecmp_m(domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)) != 0) {
 521                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 522                                           domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)));
 523                                 return NT_STATUS_LOGON_FAILURE;
 524                         }
 525                 } else {
 526                         DEBUG(3, ("Request for schannel to without domain\n"));
 527                         return NT_STATUS_LOGON_FAILURE;
 528                 }
 529
 530                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_COMPUTER_NAME) {
 531                         workstation = bind_schannel.oem_netbios_computer.a;
 532                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME) {
 533                         workstation = bind_schannel.utf8_netbios_computer.u;
 534                 } else {
 535                         DEBUG(3, ("Request for schannel to without netbios workstation\n"));
 536                         return NT_STATUS_LOGON_FAILURE;
 537                 }
 538
 539                 status = schannel_get_creds_state(out_mem_ctx,
 540                                                   gensec_security->settings->lp_ctx,
 541                                                   workstation, &creds);
 542                 if (!NT_STATUS_IS_OK(status)) {
 543                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 544                                   workstation, nt_errstr(status)));
 545                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 546                                 return NT_STATUS_LOGON_FAILURE;
 547                         }
 548                         return status;
 549                 }
 550
 551                 state = netsec_create_state(gensec_security,
 552                                             creds, false /* not initiator */);
 553                 if (state == NULL) {
 554                         return NT_STATUS_NO_MEMORY;
 555                 }
 556                 gensec_security->private_data = state;
 557
 558                 bind_schannel_ack.MessageType = NL_NEGOTIATE_RESPONSE;
 559                 bind_schannel_ack.Flags = 0;
 560                 bind_schannel_ack.Buffer.dummy = 0x6c0000; /* actually I think
 561                                                             * this does not have
 562                                                             * any meaning here
 563                                                             * - gd */
 564
 565                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack,
 566                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 567                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 568                         status = ndr_map_error2ntstatus(ndr_err);
 569                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 570                                   workstation, nt_errstr(status)));
 571                         return status;
 572                 }
 573
 574                 return NT_STATUS_OK;
 575         }
 576         return NT_STATUS_INVALID_PARAMETER;
 577 }
 578
 579 /**
 580  * Returns anonymous credentials for schannel, matching Win2k3.
 581  *
 582  */
 583
 584 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 585                                       TALLOC_CTX *mem_ctx,
 586                                       struct auth_session_info **_session_info)
 587 {
 588         return auth_anonymous_session_info(mem_ctx, gensec_security->settings->lp_ctx, _session_info);
 589 }
 590
 591 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 592 {
 593         return NT_STATUS_OK;
 594 }
 595
 596 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 597 {
 598         return NT_STATUS_OK;
 599 }
 600
 601 static bool schannel_have_feature(struct gensec_security *gensec_security,
 602                                          uint32_t feature)
 603 {
 604         if (feature & (GENSEC_FEATURE_SIGN |
 605                        GENSEC_FEATURE_SEAL)) {
 606                 return true;
 607         }
 608         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 609                 return true;
 610         }
 611         return false;
 612 }
 613
 614 /*
 615   unseal a packet
 616 */
 617 static NTSTATUS schannel_unseal_packet(struct gensec_security *gensec_security,
 618                                        uint8_t *data, size_t length,
 619                                        const uint8_t *whole_pdu, size_t pdu_length,
 620                                        const DATA_BLOB *sig)
 621 {
 622         struct schannel_state *state =
 623                 talloc_get_type_abort(gensec_security->private_data,
 624                 struct schannel_state);
 625
 626         return netsec_incoming_packet(state, true,
 627                                       discard_const_p(uint8_t, data),
 628                                       length, sig);
 629 }
 630
 631 /*
 632   check the signature on a packet
 633 */
 634 static NTSTATUS schannel_check_packet(struct gensec_security *gensec_security,
 635                                       const uint8_t *data, size_t length,
 636                                       const uint8_t *whole_pdu, size_t pdu_length,
 637                                       const DATA_BLOB *sig)
 638 {
 639         struct schannel_state *state =
 640                 talloc_get_type_abort(gensec_security->private_data,
 641                 struct schannel_state);
 642
 643         return netsec_incoming_packet(state, false,
 644                                       discard_const_p(uint8_t, data),
 645                                       length, sig);
 646 }
 647 /*
 648   seal a packet
 649 */
 650 static NTSTATUS schannel_seal_packet(struct gensec_security *gensec_security,
 651                                      TALLOC_CTX *mem_ctx,
 652                                      uint8_t *data, size_t length,
 653                                      const uint8_t *whole_pdu, size_t pdu_length,
 654                                      DATA_BLOB *sig)
 655 {
 656         struct schannel_state *state =
 657                 talloc_get_type_abort(gensec_security->private_data,
 658                 struct schannel_state);
 659
 660         return netsec_outgoing_packet(state, mem_ctx, true,
 661                                       data, length, sig);
 662 }
 663
 664 /*
 665   sign a packet
 666 */
 667 static NTSTATUS schannel_sign_packet(struct gensec_security *gensec_security,
 668                                      TALLOC_CTX *mem_ctx,
 669                                      const uint8_t *data, size_t length,
 670                                      const uint8_t *whole_pdu, size_t pdu_length,
 671                                      DATA_BLOB *sig)
 672 {
 673         struct schannel_state *state =
 674                 talloc_get_type_abort(gensec_security->private_data,
 675                 struct schannel_state);
 676
 677         return netsec_outgoing_packet(state, mem_ctx, false,
 678                                       discard_const_p(uint8_t, data),
 679                                       length, sig);
 680 }
 681
 682 static const struct gensec_security_ops gensec_schannel_security_ops = {
 683         .name           = "schannel",
 684         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 685         .client_start   = schannel_client_start,
 686         .server_start   = schannel_server_start,
 687         .update         = schannel_update,
 688         .seal_packet    = schannel_seal_packet,
 689         .sign_packet    = schannel_sign_packet,
 690         .check_packet   = schannel_check_packet,
 691         .unseal_packet  = schannel_unseal_packet,
 692         .session_info   = schannel_session_info,
 693         .sig_size       = schannel_sig_size,
 694         .have_feature   = schannel_have_feature,
 695         .enabled        = true,
 696         .priority       = GENSEC_SCHANNEL
 697 };
 698
 699 _PUBLIC_ NTSTATUS gensec_schannel_init(void)
 700 {
 701         NTSTATUS ret;
 702         ret = gensec_register(&gensec_schannel_security_ops);
 703         if (!NT_STATUS_IS_OK(ret)) {
 704                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 705                         gensec_schannel_security_ops.name));
 706                 return ret;
 707         }
 708
 709         return ret;
 710 }