source3/smbd/seal.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    SMB Transport encryption (sealing) code - server code.
   4    Copyright (C) Jeremy Allison 2007.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "smbd/smbd.h"
  22 #include "smbd/globals.h"
  23 #include "../libcli/auth/spnego.h"
  24 #include "../auth/ntlmssp/ntlmssp.h"
  25 #include "ntlmssp_wrap.h"
  26 #include "../libcli/smb/smb_seal.h"
  27 #include "../lib/util/asn1.h"
  28 #include "auth.h"
  29 #include "libsmb/libsmb.h"
  30 #include "../lib/tsocket/tsocket.h"
  31 #include "auth/gensec/gensec.h"
  32
  33 /******************************************************************************
  34  Server side encryption.
  35 ******************************************************************************/
  36
  37 /******************************************************************************
  38  Return global enc context - this must change if we ever do multiple contexts.
  39 ******************************************************************************/
  40
  41 static uint16_t srv_enc_ctx(const struct smb_trans_enc_state *es)
  42 {
  43         return es->enc_ctx_num;
  44 }
  45
  46 /******************************************************************************
  47  Is this an incoming encrypted packet ?
  48 ******************************************************************************/
  49
  50 bool is_encrypted_packet(struct smbd_server_connection *sconn,
  51                          const uint8_t *inbuf)
  52 {
  53         NTSTATUS status;
  54         uint16_t enc_num;
  55
  56         /* Ignore non-session messages or non 0xFF'E' messages. */
  57         if(CVAL(inbuf,0)
  58            || (smb_len(inbuf) < 8)
  59            || !(inbuf[4] == 0xFF && inbuf[5] == 'E')) {
  60                 return false;
  61         }
  62
  63         status = get_enc_ctx_num(inbuf, &enc_num);
  64         if (!NT_STATUS_IS_OK(status)) {
  65                 return false;
  66         }
  67
  68         /* Encrypted messages are 0xFF'E'<ctx> */
  69         if (srv_trans_enc_ctx && enc_num == srv_enc_ctx(srv_trans_enc_ctx)) {
  70                 return true;
  71         }
  72         return false;
  73 }
  74
  75 /******************************************************************************
  76  Create an auth_ntlmssp_state and ensure pointer copy is correct.
  77 ******************************************************************************/
  78
  79 static NTSTATUS make_auth_ntlmssp(const struct tsocket_address *remote_address,
  80                                   struct smb_trans_enc_state *es)
  81 {
  82         struct auth_ntlmssp_state *auth_ntlmssp_state;
  83         NTSTATUS status = auth_ntlmssp_prepare(remote_address,
  84                                                &auth_ntlmssp_state);
  85         if (!NT_STATUS_IS_OK(status)) {
  86                 return nt_status_squash(status);
  87         }
  88
  89         gensec_want_feature(auth_ntlmssp_state->gensec_security, GENSEC_FEATURE_SEAL);
  90
  91         status = auth_ntlmssp_start(auth_ntlmssp_state);
  92
  93         if (!NT_STATUS_IS_OK(status)) {
  94                 TALLOC_FREE(auth_ntlmssp_state);
  95                 return nt_status_squash(status);
  96         }
  97
  98         /* We do not need the auth_ntlmssp layer any more, which was
  99          * allocated on NULL, so promote gensec_security to the NULL
 100          * context */
 101         es->s.gensec_security = talloc_move(NULL, &auth_ntlmssp_state->gensec_security);
 102         TALLOC_FREE(auth_ntlmssp_state);
 103
 104         return status;
 105 }
 106
 107 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
 108
 109 /******************************************************************************
 110  Import a name.
 111 ******************************************************************************/
 112
 113 static NTSTATUS get_srv_gss_creds(const char *service,
 114                                 const char *name,
 115                                 gss_cred_usage_t cred_type,
 116                                 gss_cred_id_t *p_srv_cred)
 117 {
 118         OM_uint32 ret;
 119         OM_uint32 min;
 120         gss_name_t srv_name;
 121         gss_buffer_desc input_name;
 122         char *host_princ_s = NULL;
 123         NTSTATUS status = NT_STATUS_OK;
 124
 125         gss_OID_desc nt_hostbased_service =
 126         {10, discard_const_p(char, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x01\x04")};
 127
 128         if (asprintf(&host_princ_s, "%s@%s", service, name) == -1) {
 129                 return NT_STATUS_NO_MEMORY;
 130         }
 131
 132         input_name.value = host_princ_s;
 133         input_name.length = strlen(host_princ_s) + 1;
 134
 135         ret = gss_import_name(&min,
 136                                 &input_name,
 137                                 &nt_hostbased_service,
 138                                 &srv_name);
 139
 140         DEBUG(10,("get_srv_gss_creds: imported name %s\n",
 141                 host_princ_s ));
 142
 143         if (ret != GSS_S_COMPLETE) {
 144                 SAFE_FREE(host_princ_s);
 145                 return map_nt_error_from_gss(ret, min);
 146         }
 147
 148         /*
 149          * We're accessing the krb5.keytab file here.
 150          * ensure we have permissions to do so.
 151          */
 152         become_root();
 153
 154         ret = gss_acquire_cred(&min,
 155                                 srv_name,
 156                                 GSS_C_INDEFINITE,
 157                                 GSS_C_NULL_OID_SET,
 158                                 cred_type,
 159                                 p_srv_cred,
 160                                 NULL,
 161                                 NULL);
 162         unbecome_root();
 163
 164         if (ret != GSS_S_COMPLETE) {
 165                 ADS_STATUS adss = ADS_ERROR_GSS(ret, min);
 166                 DEBUG(10,("get_srv_gss_creds: gss_acquire_cred failed with %s\n",
 167                         ads_errstr(adss)));
 168                 status = map_nt_error_from_gss(ret, min);
 169         }
 170
 171         SAFE_FREE(host_princ_s);
 172         gss_release_name(&min, &srv_name);
 173         return status;
 174 }
 175
 176 /******************************************************************************
 177  Create a gss state.
 178  Try and get the cifs/server@realm principal first, then fall back to
 179  host/server@realm.
 180 ******************************************************************************/
 181
 182 static NTSTATUS make_auth_gss(struct smb_trans_enc_state *es)
 183 {
 184         NTSTATUS status;
 185         gss_cred_id_t srv_cred;
 186         fstring fqdn;
 187
 188         name_to_fqdn(fqdn, lp_netbios_name());
 189         strlower_m(fqdn);
 190
 191         status = get_srv_gss_creds("cifs", fqdn, GSS_C_ACCEPT, &srv_cred);
 192         if (!NT_STATUS_IS_OK(status)) {
 193                 status = get_srv_gss_creds("host", fqdn, GSS_C_ACCEPT, &srv_cred);
 194                 if (!NT_STATUS_IS_OK(status)) {
 195                         return nt_status_squash(status);
 196                 }
 197         }
 198
 199         es->s.gss_state = SMB_MALLOC_P(struct smb_tran_enc_state_gss);
 200         if (!es->s.gss_state) {
 201                 OM_uint32 min;
 202                 gss_release_cred(&min, &srv_cred);
 203                 return NT_STATUS_NO_MEMORY;
 204         }
 205         ZERO_STRUCTP(es->s.gss_state);
 206         es->s.gss_state->creds = srv_cred;
 207
 208         /* No context yet. */
 209         es->s.gss_state->gss_ctx = GSS_C_NO_CONTEXT;
 210
 211         return NT_STATUS_OK;
 212 }
 213 #endif
 214
 215 /******************************************************************************
 216  Shutdown a server encryption context.
 217 ******************************************************************************/
 218
 219 static void srv_free_encryption_context(struct smb_trans_enc_state **pp_es)
 220 {
 221         struct smb_trans_enc_state *es = *pp_es;
 222
 223         if (!es) {
 224                 return;
 225         }
 226
 227         common_free_encryption_state(&es);
 228
 229         SAFE_FREE(es);
 230         *pp_es = NULL;
 231 }
 232
 233 /******************************************************************************
 234  Create a server encryption context.
 235 ******************************************************************************/
 236
 237 static NTSTATUS make_srv_encryption_context(const struct tsocket_address *remote_address,
 238                                             enum smb_trans_enc_type smb_enc_type,
 239                                             struct smb_trans_enc_state **pp_es)
 240 {
 241         struct smb_trans_enc_state *es;
 242
 243         *pp_es = NULL;
 244
 245         ZERO_STRUCTP(partial_srv_trans_enc_ctx);
 246         es = SMB_MALLOC_P(struct smb_trans_enc_state);
 247         if (!es) {
 248                 return NT_STATUS_NO_MEMORY;
 249         }
 250         ZERO_STRUCTP(es);
 251         es->smb_enc_type = smb_enc_type;
 252         switch (smb_enc_type) {
 253                 case SMB_TRANS_ENC_NTLM:
 254                         {
 255                                 NTSTATUS status = make_auth_ntlmssp(remote_address,
 256                                                                     es);
 257                                 if (!NT_STATUS_IS_OK(status)) {
 258                                         srv_free_encryption_context(&es);
 259                                         return status;
 260                                 }
 261                         }
 262                         break;
 263
 264 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
 265                 case SMB_TRANS_ENC_GSS:
 266                         /* Acquire our credentials by calling gss_acquire_cred here. */
 267                         {
 268                                 NTSTATUS status = make_auth_gss(es);
 269                                 if (!NT_STATUS_IS_OK(status)) {
 270                                         srv_free_encryption_context(&es);
 271                                         return status;
 272                                 }
 273                         }
 274                         break;
 275 #endif
 276                 default:
 277                         srv_free_encryption_context(&es);
 278                         return NT_STATUS_INVALID_PARAMETER;
 279         }
 280         *pp_es = es;
 281         return NT_STATUS_OK;
 282 }
 283
 284 /******************************************************************************
 285  Free an encryption-allocated buffer.
 286 ******************************************************************************/
 287
 288 void srv_free_enc_buffer(struct smbd_server_connection *sconn, char *buf)
 289 {
 290         /* We know this is an smb buffer, and we
 291          * didn't malloc, only copy, for a keepalive,
 292          * so ignore non-session messages. */
 293
 294         if(CVAL(buf,0)) {
 295                 return;
 296         }
 297
 298         if (srv_trans_enc_ctx) {
 299                 common_free_enc_buffer(srv_trans_enc_ctx, buf);
 300         }
 301 }
 302
 303 /******************************************************************************
 304  Decrypt an incoming buffer.
 305 ******************************************************************************/
 306
 307 NTSTATUS srv_decrypt_buffer(struct smbd_server_connection *sconn, char *buf)
 308 {
 309         /* Ignore non-session messages. */
 310         if(CVAL(buf,0)) {
 311                 return NT_STATUS_OK;
 312         }
 313
 314         if (srv_trans_enc_ctx) {
 315                 return common_decrypt_buffer(srv_trans_enc_ctx, buf);
 316         }
 317
 318         return NT_STATUS_OK;
 319 }
 320
 321 /******************************************************************************
 322  Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
 323 ******************************************************************************/
 324
 325 NTSTATUS srv_encrypt_buffer(struct smbd_server_connection *sconn, char *buf,
 326                             char **buf_out)
 327 {
 328         *buf_out = buf;
 329
 330         /* Ignore non-session messages. */
 331         if(CVAL(buf,0)) {
 332                 return NT_STATUS_OK;
 333         }
 334
 335         if (srv_trans_enc_ctx) {
 336                 return common_encrypt_buffer(srv_trans_enc_ctx, buf, buf_out);
 337         }
 338         /* Not encrypting. */
 339         return NT_STATUS_OK;
 340 }
 341
 342 /******************************************************************************
 343  Do the gss encryption negotiation. Parameters are in/out.
 344  Until success we do everything on the partial enc ctx.
 345 ******************************************************************************/
 346
 347 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
 348 static NTSTATUS srv_enc_spnego_gss_negotiate(const struct tsocket_address *remote_address,
 349                                              unsigned char **ppdata,
 350                                              size_t *p_data_size,
 351                                              DATA_BLOB secblob)
 352 {
 353         OM_uint32 ret;
 354         OM_uint32 min;
 355         OM_uint32 flags = 0;
 356         gss_buffer_desc in_buf, out_buf;
 357         struct smb_tran_enc_state_gss *gss_state;
 358         DATA_BLOB auth_reply = data_blob_null;
 359         DATA_BLOB response = data_blob_null;
 360         NTSTATUS status;
 361
 362         if (!partial_srv_trans_enc_ctx) {
 363                 status = make_srv_encryption_context(remote_address,
 364                                                      SMB_TRANS_ENC_GSS,
 365                                                      &partial_srv_trans_enc_ctx);
 366                 if (!NT_STATUS_IS_OK(status)) {
 367                         return status;
 368                 }
 369         }
 370
 371         gss_state = partial_srv_trans_enc_ctx->s.gss_state;
 372
 373         in_buf.value = secblob.data;
 374         in_buf.length = secblob.length;
 375
 376         out_buf.value = NULL;
 377         out_buf.length = 0;
 378
 379         become_root();
 380
 381         ret = gss_accept_sec_context(&min,
 382                                 &gss_state->gss_ctx,
 383                                 gss_state->creds,
 384                                 &in_buf,
 385                                 GSS_C_NO_CHANNEL_BINDINGS,
 386                                 NULL,
 387                                 NULL,           /* Ignore oids. */
 388                                 &out_buf,       /* To return. */
 389                                 &flags,
 390                                 NULL,           /* Ingore time. */
 391                                 NULL);          /* Ignore delegated creds. */
 392         unbecome_root();
 393
 394         status = gss_err_to_ntstatus(ret, min);
 395         if (ret != GSS_S_COMPLETE && ret != GSS_S_CONTINUE_NEEDED) {
 396                 return status;
 397         }
 398
 399         /* Ensure we've got sign+seal available. */
 400         if (ret == GSS_S_COMPLETE) {
 401                 if ((flags & (GSS_C_INTEG_FLAG|GSS_C_CONF_FLAG|GSS_C_REPLAY_FLAG|GSS_C_SEQUENCE_FLAG)) !=
 402                                 (GSS_C_INTEG_FLAG|GSS_C_CONF_FLAG|GSS_C_REPLAY_FLAG|GSS_C_SEQUENCE_FLAG)) {
 403                         DEBUG(0,("srv_enc_spnego_gss_negotiate: quality of service not good enough "
 404                                 "for SMB sealing.\n"));
 405                         gss_release_buffer(&min, &out_buf);
 406                         return NT_STATUS_ACCESS_DENIED;
 407                 }
 408         }
 409
 410         auth_reply = data_blob(out_buf.value, out_buf.length);
 411         gss_release_buffer(&min, &out_buf);
 412
 413         /* Wrap in SPNEGO. */
 414         response = spnego_gen_auth_response(talloc_tos(), &auth_reply, status, OID_KERBEROS5);
 415         data_blob_free(&auth_reply);
 416
 417         SAFE_FREE(*ppdata);
 418         *ppdata = (unsigned char *)memdup(response.data, response.length);
 419         if ((*ppdata) == NULL && response.length > 0) {
 420                 status = NT_STATUS_NO_MEMORY;
 421         }
 422         *p_data_size = response.length;
 423
 424         data_blob_free(&response);
 425
 426         return status;
 427 }
 428 #endif
 429
 430 /******************************************************************************
 431  Do the NTLM SPNEGO (or raw) encryption negotiation. Parameters are in/out.
 432  Until success we do everything on the partial enc ctx.
 433 ******************************************************************************/
 434
 435 static NTSTATUS srv_enc_ntlm_negotiate(const struct tsocket_address *remote_address,
 436                                        unsigned char **ppdata,
 437                                        size_t *p_data_size,
 438                                        DATA_BLOB secblob,
 439                                        bool spnego_wrap)
 440 {
 441         NTSTATUS status;
 442         DATA_BLOB chal = data_blob_null;
 443         DATA_BLOB response = data_blob_null;
 444
 445         status = make_srv_encryption_context(remote_address,
 446                                              SMB_TRANS_ENC_NTLM,
 447                                              &partial_srv_trans_enc_ctx);
 448         if (!NT_STATUS_IS_OK(status)) {
 449                 return status;
 450         }
 451
 452         status = gensec_update(partial_srv_trans_enc_ctx->s.gensec_security,
 453                                talloc_tos(), NULL,
 454                                secblob, &chal);
 455
 456         /* status here should be NT_STATUS_MORE_PROCESSING_REQUIRED
 457          * for success ... */
 458
 459         if (spnego_wrap) {
 460                 response = spnego_gen_auth_response(talloc_tos(), &chal, status, OID_NTLMSSP);
 461                 data_blob_free(&chal);
 462         } else {
 463                 /* Return the raw blob. */
 464                 response = chal;
 465         }
 466
 467         SAFE_FREE(*ppdata);
 468         *ppdata = (unsigned char *)memdup(response.data, response.length);
 469         if ((*ppdata) == NULL && response.length > 0) {
 470                 status = NT_STATUS_NO_MEMORY;
 471         }
 472         *p_data_size = response.length;
 473         data_blob_free(&response);
 474
 475         return status;
 476 }
 477
 478 /******************************************************************************
 479  Do the SPNEGO encryption negotiation. Parameters are in/out.
 480  Based off code in smbd/sesssionsetup.c
 481  Until success we do everything on the partial enc ctx.
 482 ******************************************************************************/
 483
 484 static NTSTATUS srv_enc_spnego_negotiate(connection_struct *conn,
 485                                         unsigned char **ppdata,
 486                                         size_t *p_data_size,
 487                                         unsigned char **pparam,
 488                                         size_t *p_param_size)
 489 {
 490         NTSTATUS status;
 491         DATA_BLOB blob = data_blob_null;
 492         DATA_BLOB secblob = data_blob_null;
 493         char *kerb_mech = NULL;
 494
 495         blob = data_blob_const(*ppdata, *p_data_size);
 496
 497         status = parse_spnego_mechanisms(talloc_tos(), blob, &secblob, &kerb_mech);
 498         if (!NT_STATUS_IS_OK(status)) {
 499                 return nt_status_squash(status);
 500         }
 501
 502         /* We should have no partial context at this point. */
 503
 504         srv_free_encryption_context(&partial_srv_trans_enc_ctx);
 505
 506         if (kerb_mech) {
 507                 TALLOC_FREE(kerb_mech);
 508
 509 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
 510                 status = srv_enc_spnego_gss_negotiate(conn->sconn->remote_address,
 511                                                       ppdata,
 512                                                       p_data_size,
 513                                                       secblob);
 514 #else
 515                 /* Currently we don't SPNEGO negotiate
 516                  * back to NTLMSSP as we do in sessionsetupX. We should... */
 517                 return NT_STATUS_LOGON_FAILURE;
 518 #endif
 519         } else {
 520                 status = srv_enc_ntlm_negotiate(conn->sconn->remote_address,
 521                                                 ppdata,
 522                                                 p_data_size,
 523                                                 secblob,
 524                                                 true);
 525         }
 526
 527         data_blob_free(&secblob);
 528
 529         if (!NT_STATUS_EQUAL(status,NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(status)) {
 530                 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
 531                 return nt_status_squash(status);
 532         }
 533
 534         if (NT_STATUS_IS_OK(status)) {
 535                 /* Return the context we're using for this encryption state. */
 536                 if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
 537                         return NT_STATUS_NO_MEMORY;
 538                 }
 539                 SSVAL(*pparam,0,partial_srv_trans_enc_ctx->enc_ctx_num);
 540                 *p_param_size = 2;
 541         }
 542
 543         return status;
 544 }
 545
 546 /******************************************************************************
 547  Complete a SPNEGO encryption negotiation. Parameters are in/out.
 548  We only get this for a NTLM auth second stage.
 549 ******************************************************************************/
 550
 551 static NTSTATUS srv_enc_spnego_ntlm_auth(connection_struct *conn,
 552                                         unsigned char **ppdata,
 553                                         size_t *p_data_size,
 554                                         unsigned char **pparam,
 555                                         size_t *p_param_size)
 556 {
 557         NTSTATUS status;
 558         DATA_BLOB blob = data_blob_null;
 559         DATA_BLOB auth = data_blob_null;
 560         DATA_BLOB auth_reply = data_blob_null;
 561         DATA_BLOB response = data_blob_null;
 562         struct smb_trans_enc_state *es = partial_srv_trans_enc_ctx;
 563
 564         /* We must have a partial context here. */
 565
 566         if (!es || es->s.gensec_security == NULL || es->smb_enc_type != SMB_TRANS_ENC_NTLM) {
 567                 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
 568                 return NT_STATUS_INVALID_PARAMETER;
 569         }
 570
 571         blob = data_blob_const(*ppdata, *p_data_size);
 572         if (!spnego_parse_auth(talloc_tos(), blob, &auth)) {
 573                 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
 574                 return NT_STATUS_INVALID_PARAMETER;
 575         }
 576
 577         status = gensec_update(es->s.gensec_security, talloc_tos(), NULL, auth, &auth_reply);
 578         data_blob_free(&auth);
 579
 580         /* From RFC4178.
 581          *
 582          *    supportedMech
 583          *
 584          *          This field SHALL only be present in the first reply from the
 585          *                target.
 586          * So set mechOID to NULL here.
 587          */
 588
 589         response = spnego_gen_auth_response(talloc_tos(), &auth_reply, status, NULL);
 590         data_blob_free(&auth_reply);
 591
 592         if (NT_STATUS_IS_OK(status)) {
 593                 /* Return the context we're using for this encryption state. */
 594                 if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
 595                         return NT_STATUS_NO_MEMORY;
 596                 }
 597                 SSVAL(*pparam,0,es->enc_ctx_num);
 598                 *p_param_size = 2;
 599         }
 600
 601         SAFE_FREE(*ppdata);
 602         *ppdata = (unsigned char *)memdup(response.data, response.length);
 603         if ((*ppdata) == NULL && response.length > 0)
 604                 return NT_STATUS_NO_MEMORY;
 605         *p_data_size = response.length;
 606         data_blob_free(&response);
 607         return status;
 608 }
 609
 610 /******************************************************************************
 611  Raw NTLM encryption negotiation. Parameters are in/out.
 612  This function does both steps.
 613 ******************************************************************************/
 614
 615 static NTSTATUS srv_enc_raw_ntlm_auth(connection_struct *conn,
 616                                         unsigned char **ppdata,
 617                                         size_t *p_data_size,
 618                                         unsigned char **pparam,
 619                                         size_t *p_param_size)
 620 {
 621         NTSTATUS status;
 622         DATA_BLOB blob = data_blob_const(*ppdata, *p_data_size);
 623         DATA_BLOB response = data_blob_null;
 624         struct smb_trans_enc_state *es;
 625
 626         if (!partial_srv_trans_enc_ctx) {
 627                 /* This is the initial step. */
 628                 status = srv_enc_ntlm_negotiate(conn->sconn->remote_address,
 629                                                 ppdata,
 630                                                 p_data_size,
 631                                                 blob,
 632                                                 false);
 633                 if (!NT_STATUS_EQUAL(status,NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(status)) {
 634                         srv_free_encryption_context(&partial_srv_trans_enc_ctx);
 635                         return nt_status_squash(status);
 636                 }
 637                 return status;
 638         }
 639
 640         es = partial_srv_trans_enc_ctx;
 641         if (!es || es->s.gensec_security == NULL || es->smb_enc_type != SMB_TRANS_ENC_NTLM) {
 642                 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
 643                 return NT_STATUS_INVALID_PARAMETER;
 644         }
 645
 646         /* Second step. */
 647         status = gensec_update(partial_srv_trans_enc_ctx->s.gensec_security,
 648                                talloc_tos(), NULL,
 649                                blob, &response);
 650
 651         if (NT_STATUS_IS_OK(status)) {
 652                 /* Return the context we're using for this encryption state. */
 653                 if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
 654                         return NT_STATUS_NO_MEMORY;
 655                 }
 656                 SSVAL(*pparam, 0, es->enc_ctx_num);
 657                 *p_param_size = 2;
 658         }
 659
 660         /* Return the raw blob. */
 661         SAFE_FREE(*ppdata);
 662         *ppdata = (unsigned char *)memdup(response.data, response.length);
 663         if ((*ppdata) == NULL && response.length > 0)
 664                 return NT_STATUS_NO_MEMORY;
 665         *p_data_size = response.length;
 666         data_blob_free(&response);
 667         return status;
 668 }
 669
 670 /******************************************************************************
 671  Do the SPNEGO encryption negotiation. Parameters are in/out.
 672 ******************************************************************************/
 673
 674 NTSTATUS srv_request_encryption_setup(connection_struct *conn,
 675                                         unsigned char **ppdata,
 676                                         size_t *p_data_size,
 677                                         unsigned char **pparam,
 678                                         size_t *p_param_size)
 679 {
 680         unsigned char *pdata = *ppdata;
 681
 682         SAFE_FREE(*pparam);
 683         *p_param_size = 0;
 684
 685         if (*p_data_size < 1) {
 686                 return NT_STATUS_INVALID_PARAMETER;
 687         }
 688
 689         if (pdata[0] == ASN1_APPLICATION(0)) {
 690                 /* its a negTokenTarg packet */
 691                 return srv_enc_spnego_negotiate(conn, ppdata, p_data_size, pparam, p_param_size);
 692         }
 693
 694         if (pdata[0] == ASN1_CONTEXT(1)) {
 695                 /* It's an auth packet */
 696                 return srv_enc_spnego_ntlm_auth(conn, ppdata, p_data_size, pparam, p_param_size);
 697         }
 698
 699         /* Maybe it's a raw unwrapped auth ? */
 700         if (*p_data_size < 7) {
 701                 return NT_STATUS_INVALID_PARAMETER;
 702         }
 703
 704         if (strncmp((char *)pdata, "NTLMSSP", 7) == 0) {
 705                 return srv_enc_raw_ntlm_auth(conn, ppdata, p_data_size, pparam, p_param_size);
 706         }
 707
 708         DEBUG(1,("srv_request_encryption_setup: Unknown packet\n"));
 709
 710         return NT_STATUS_LOGON_FAILURE;
 711 }
 712
 713 /******************************************************************************
 714  Negotiation was successful - turn on server-side encryption.
 715 ******************************************************************************/
 716
 717 static NTSTATUS check_enc_good(struct smb_trans_enc_state *es)
 718 {
 719         if (!es) {
 720                 return NT_STATUS_LOGON_FAILURE;
 721         }
 722
 723         if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
 724                 if (!gensec_have_feature(es->s.gensec_security, GENSEC_FEATURE_SIGN)) {
 725                         return NT_STATUS_INVALID_PARAMETER;
 726                 }
 727
 728                 if (!gensec_have_feature(es->s.gensec_security, GENSEC_FEATURE_SEAL)) {
 729                         return NT_STATUS_INVALID_PARAMETER;
 730                 }
 731         }
 732         /* Todo - check gssapi case. */
 733
 734         return NT_STATUS_OK;
 735 }
 736
 737 /******************************************************************************
 738  Negotiation was successful - turn on server-side encryption.
 739 ******************************************************************************/
 740
 741 NTSTATUS srv_encryption_start(connection_struct *conn)
 742 {
 743         NTSTATUS status;
 744
 745         /* Check that we are really doing sign+seal. */
 746         status = check_enc_good(partial_srv_trans_enc_ctx);
 747         if (!NT_STATUS_IS_OK(status)) {
 748                 return status;
 749         }
 750         /* Throw away the context we're using currently (if any). */
 751         srv_free_encryption_context(&srv_trans_enc_ctx);
 752
 753         /* Steal the partial pointer. Deliberate shallow copy. */
 754         srv_trans_enc_ctx = partial_srv_trans_enc_ctx;
 755         srv_trans_enc_ctx->enc_on = true;
 756
 757         partial_srv_trans_enc_ctx = NULL;
 758
 759         DEBUG(1,("srv_encryption_start: context negotiated\n"));
 760         return NT_STATUS_OK;
 761 }
 762
 763 /******************************************************************************
 764  Shutdown all server contexts.
 765 ******************************************************************************/
 766
 767 void server_encryption_shutdown(struct smbd_server_connection *sconn)
 768 {
 769         srv_free_encryption_context(&partial_srv_trans_enc_ctx);
 770         srv_free_encryption_context(&srv_trans_enc_ctx);
 771 }