source/auth/ntlmssp/ntlmssp_server.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    handle NLTMSSP, client server side parsing
   5
   6    Copyright (C) Andrew Tridgell      2001
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2005
   8    Copyright (C) Stefan Metzmacher 2005
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23 */
  24
  25 #include "includes.h"
  26 #include "auth/auth.h"
  27 #include "auth/ntlmssp/ntlmssp.h"
  28 #include "lib/crypto/crypto.h"
  29 #include "pstring.h"
  30 #include "system/filesys.h"
  31
  32 /**
  33  * Set a username on an NTLMSSP context - ensures it is talloc()ed
  34  *
  35  */
  36
  37 static NTSTATUS ntlmssp_set_username(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *user)
  38 {
  39         if (!user) {
  40                 /* it should be at least "" */
  41                 DEBUG(1, ("NTLMSSP failed to set username - cannot accept NULL username\n"));
  42                 return NT_STATUS_INVALID_PARAMETER;
  43         }
  44         gensec_ntlmssp_state->user = talloc_strdup(gensec_ntlmssp_state, user);
  45         if (!gensec_ntlmssp_state->user) {
  46                 return NT_STATUS_NO_MEMORY;
  47         }
  48         return NT_STATUS_OK;
  49 }
  50
  51 /**
  52  * Set a domain on an NTLMSSP context - ensures it is talloc()ed
  53  *
  54  */
  55 static NTSTATUS ntlmssp_set_domain(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *domain)
  56 {
  57         gensec_ntlmssp_state->domain = talloc_strdup(gensec_ntlmssp_state, domain);
  58         if (!gensec_ntlmssp_state->domain) {
  59                 return NT_STATUS_NO_MEMORY;
  60         }
  61         return NT_STATUS_OK;
  62 }
  63
  64 /**
  65  * Set a workstation on an NTLMSSP context - ensures it is talloc()ed
  66  *
  67  */
  68 static NTSTATUS ntlmssp_set_workstation(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *workstation)
  69 {
  70         gensec_ntlmssp_state->workstation = talloc_strdup(gensec_ntlmssp_state, workstation);
  71         if (!gensec_ntlmssp_state->workstation) {
  72                 return NT_STATUS_NO_MEMORY;
  73         }
  74         return NT_STATUS_OK;
  75 }
  76
  77 /**
  78  * Determine correct target name flags for reply, given server role
  79  * and negotiated flags
  80  *
  81  * @param gensec_ntlmssp_state NTLMSSP State
  82  * @param neg_flags The flags from the packet
  83  * @param chal_flags The flags to be set in the reply packet
  84  * @return The 'target name' string.
  85  */
  86
  87 static const char *ntlmssp_target_name(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
  88                                        uint32_t neg_flags, uint32_t *chal_flags)
  89 {
  90         if (neg_flags & NTLMSSP_REQUEST_TARGET) {
  91                 *chal_flags |= NTLMSSP_CHAL_TARGET_INFO;
  92                 *chal_flags |= NTLMSSP_REQUEST_TARGET;
  93                 if (gensec_ntlmssp_state->server_role == ROLE_STANDALONE) {
  94                         *chal_flags |= NTLMSSP_TARGET_TYPE_SERVER;
  95                         return gensec_ntlmssp_state->server_name;
  96                 } else {
  97                         *chal_flags |= NTLMSSP_TARGET_TYPE_DOMAIN;
  98                         return gensec_ntlmssp_state->get_domain();
  99                 };
 100         } else {
 101                 return "";
 102         }
 103 }
 104
 105 /*
 106   Andrew, please remove these totally bogus calls when you get time
 107 */
 108 static BOOL get_myfullname(char *my_name)
 109 {
 110         pstring hostname;
 111
 112         *hostname = 0;
 113
 114         /* get my host name */
 115         if (gethostname(hostname, sizeof(hostname)) == -1) {
 116                 DEBUG(0,("gethostname failed\n"));
 117                 return False;
 118         }
 119
 120         /* Ensure null termination. */
 121         hostname[sizeof(hostname)-1] = '\0';
 122
 123         if (my_name)
 124                 fstrcpy(my_name, hostname);
 125         return True;
 126 }
 127
 128 static BOOL get_mydomname(char *my_domname)
 129 {
 130         pstring hostname;
 131         char *p;
 132
 133         /* arrgh! relies on full name in system */
 134
 135         *hostname = 0;
 136         /* get my host name */
 137         if (gethostname(hostname, sizeof(hostname)) == -1) {
 138                 DEBUG(0,("gethostname failed\n"));
 139                 return False;
 140         }
 141
 142         /* Ensure null termination. */
 143         hostname[sizeof(hostname)-1] = '\0';
 144
 145         p = strchr_m(hostname, '.');
 146
 147         if (!p)
 148                 return False;
 149
 150         p++;
 151
 152         if (my_domname)
 153                 fstrcpy(my_domname, p);
 154
 155         return True;
 156 }
 157
 158
 159
 160 /**
 161  * Next state function for the Negotiate packet
 162  *
 163  * @param gensec_security GENSEC state
 164  * @param out_mem_ctx Memory context for *out
 165  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
 166  * @param out The reply, as an allocated DATA_BLOB, caller to free.
 167  * @return Errors or MORE_PROCESSING_REQUIRED if (normal) a reply is required.
 168  */
 169
 170 NTSTATUS ntlmssp_server_negotiate(struct gensec_security *gensec_security,
 171                                   TALLOC_CTX *out_mem_ctx,
 172                                   const DATA_BLOB in, DATA_BLOB *out)
 173 {
 174         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 175         DATA_BLOB struct_blob;
 176         fstring dnsname, dnsdomname;
 177         uint32_t neg_flags = 0;
 178         uint32_t ntlmssp_command, chal_flags;
 179         char *cliname=NULL, *domname=NULL;
 180         const uint8_t *cryptkey;
 181         const char *target_name;
 182
 183         /* parse the NTLMSSP packet */
 184 #if 0
 185         file_save("ntlmssp_negotiate.dat", request.data, request.length);
 186 #endif
 187
 188         if (in.length) {
 189                 BOOL parse_ok = msrpc_parse(out_mem_ctx,
 190                                  &in, "CddAA",
 191                                  "NTLMSSP",
 192                                  &ntlmssp_command,
 193                                  &neg_flags,
 194                                  &cliname,
 195                                  &domname);
 196                 if (!parse_ok) {
 197                         parse_ok = msrpc_parse(out_mem_ctx,
 198                                          &in, "CddUU",
 199                                          "NTLMSSP",
 200                                          &ntlmssp_command,
 201                                          &neg_flags,
 202                                          &cliname,
 203                                          &domname);
 204                 }
 205                 if (!parse_ok) {
 206                         DEBUG(1, ("ntlmssp_server_negotiate: failed to parse NTLMSSP:\n"));
 207                         dump_data(2, in.data, in.length);
 208                         return NT_STATUS_INVALID_PARAMETER;
 209                 }
 210
 211                 debug_ntlmssp_flags(neg_flags);
 212         }
 213
 214         ntlmssp_handle_neg_flags(gensec_ntlmssp_state, neg_flags, gensec_ntlmssp_state->allow_lm_key);
 215
 216         /* Ask our caller what challenge they would like in the packet */
 217         cryptkey = gensec_ntlmssp_state->get_challenge(gensec_ntlmssp_state);
 218
 219         /* Check if we may set the challenge */
 220         if (!gensec_ntlmssp_state->may_set_challenge(gensec_ntlmssp_state)) {
 221                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
 222         }
 223
 224         /* The flags we send back are not just the negotiated flags,
 225          * they are also 'what is in this packet'.  Therfore, we
 226          * operate on 'chal_flags' from here on
 227          */
 228
 229         chal_flags = gensec_ntlmssp_state->neg_flags;
 230
 231         /* get the right name to fill in as 'target' */
 232         target_name = ntlmssp_target_name(gensec_ntlmssp_state,
 233                                           neg_flags, &chal_flags);
 234         if (target_name == NULL)
 235                 return NT_STATUS_INVALID_PARAMETER;
 236
 237         gensec_ntlmssp_state->chal = data_blob_talloc(gensec_ntlmssp_state, cryptkey, 8);
 238         gensec_ntlmssp_state->internal_chal = data_blob_talloc(gensec_ntlmssp_state, cryptkey, 8);
 239
 240         /* This should be a 'netbios domain -> DNS domain' mapping */
 241         dnsdomname[0] = '\0';
 242         get_mydomname(dnsdomname);
 243         strlower_m(dnsdomname);
 244
 245         dnsname[0] = '\0';
 246         get_myfullname(dnsname);
 247
 248         /* This creates the 'blob' of names that appears at the end of the packet */
 249         if (chal_flags & NTLMSSP_CHAL_TARGET_INFO)
 250         {
 251                 const char *target_name_dns = "";
 252                 if (chal_flags |= NTLMSSP_TARGET_TYPE_DOMAIN) {
 253                         target_name_dns = dnsdomname;
 254                 } else if (chal_flags |= NTLMSSP_TARGET_TYPE_SERVER) {
 255                         target_name_dns = dnsname;
 256                 }
 257
 258                 msrpc_gen(out_mem_ctx,
 259                           &struct_blob, "aaaaa",
 260                           NTLMSSP_NAME_TYPE_DOMAIN, target_name,
 261                           NTLMSSP_NAME_TYPE_SERVER, gensec_ntlmssp_state->server_name,
 262                           NTLMSSP_NAME_TYPE_DOMAIN_DNS, dnsdomname,
 263                           NTLMSSP_NAME_TYPE_SERVER_DNS, dnsname,
 264                           0, "");
 265         } else {
 266                 struct_blob = data_blob(NULL, 0);
 267         }
 268
 269         {
 270                 /* Marshel the packet in the right format, be it unicode or ASCII */
 271                 const char *gen_string;
 272                 if (gensec_ntlmssp_state->unicode) {
 273                         gen_string = "CdUdbddB";
 274                 } else {
 275                         gen_string = "CdAdbddB";
 276                 }
 277
 278                 msrpc_gen(out_mem_ctx,
 279                           out, gen_string,
 280                           "NTLMSSP",
 281                           NTLMSSP_CHALLENGE,
 282                           target_name,
 283                           chal_flags,
 284                           cryptkey, 8,
 285                           0, 0,
 286                           struct_blob.data, struct_blob.length);
 287         }
 288
 289         gensec_ntlmssp_state->expected_state = NTLMSSP_AUTH;
 290
 291         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 292 }
 293
 294 /**
 295  * Next state function for the Authenticate packet
 296  *
 297  * @param gensec_ntlmssp_state NTLMSSP State
 298  * @param request The request, as a DATA_BLOB
 299  * @return Errors or NT_STATUS_OK.
 300  */
 301
 302 static NTSTATUS ntlmssp_server_preauth(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
 303                                        const DATA_BLOB request)
 304 {
 305         uint32_t ntlmssp_command, auth_flags;
 306         NTSTATUS nt_status;
 307
 308         uint8_t session_nonce_hash[16];
 309
 310         const char *parse_string;
 311         char *domain = NULL;
 312         char *user = NULL;
 313         char *workstation = NULL;
 314
 315 #if 0
 316         file_save("ntlmssp_auth.dat", request.data, request.length);
 317 #endif
 318
 319         if (gensec_ntlmssp_state->unicode) {
 320                 parse_string = "CdBBUUUBd";
 321         } else {
 322                 parse_string = "CdBBAAABd";
 323         }
 324
 325         /* zero these out */
 326         data_blob_free(&gensec_ntlmssp_state->lm_resp);
 327         data_blob_free(&gensec_ntlmssp_state->nt_resp);
 328         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 329
 330         gensec_ntlmssp_state->user = NULL;
 331         gensec_ntlmssp_state->domain = NULL;
 332         gensec_ntlmssp_state->workstation = NULL;
 333
 334         /* now the NTLMSSP encoded auth hashes */
 335         if (!msrpc_parse(gensec_ntlmssp_state,
 336                          &request, parse_string,
 337                          "NTLMSSP",
 338                          &ntlmssp_command,
 339                          &gensec_ntlmssp_state->lm_resp,
 340                          &gensec_ntlmssp_state->nt_resp,
 341                          &domain,
 342                          &user,
 343                          &workstation,
 344                          &gensec_ntlmssp_state->encrypted_session_key,
 345                          &auth_flags)) {
 346                 DEBUG(10, ("ntlmssp_server_auth: failed to parse NTLMSSP (nonfatal):\n"));
 347                 dump_data(10, request.data, request.length);
 348
 349                 /* zero this out */
 350                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 351                 auth_flags = 0;
 352
 353                 /* Try again with a shorter string (Win9X truncates this packet) */
 354                 if (gensec_ntlmssp_state->unicode) {
 355                         parse_string = "CdBBUUU";
 356                 } else {
 357                         parse_string = "CdBBAAA";
 358                 }
 359
 360                 /* now the NTLMSSP encoded auth hashes */
 361                 if (!msrpc_parse(gensec_ntlmssp_state,
 362                                  &request, parse_string,
 363                                  "NTLMSSP",
 364                                  &ntlmssp_command,
 365                                  &gensec_ntlmssp_state->lm_resp,
 366                                  &gensec_ntlmssp_state->nt_resp,
 367                                  &domain,
 368                                  &user,
 369                                  &workstation)) {
 370                         DEBUG(1, ("ntlmssp_server_auth: failed to parse NTLMSSP:\n"));
 371                         dump_data(2, request.data, request.length);
 372
 373                         return NT_STATUS_INVALID_PARAMETER;
 374                 }
 375         }
 376
 377         if (auth_flags)
 378                 ntlmssp_handle_neg_flags(gensec_ntlmssp_state, auth_flags, gensec_ntlmssp_state->allow_lm_key);
 379
 380         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_domain(gensec_ntlmssp_state, domain))) {
 381                 /* zero this out */
 382                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 383                 return nt_status;
 384         }
 385
 386         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_username(gensec_ntlmssp_state, user))) {
 387                 /* zero this out */
 388                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 389                 return nt_status;
 390         }
 391
 392         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_workstation(gensec_ntlmssp_state, workstation))) {
 393                 /* zero this out */
 394                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 395                 return nt_status;
 396         }
 397
 398         DEBUG(3,("Got user=[%s] domain=[%s] workstation=[%s] len1=%lu len2=%lu\n",
 399                  gensec_ntlmssp_state->user, gensec_ntlmssp_state->domain, gensec_ntlmssp_state->workstation, (unsigned long)gensec_ntlmssp_state->lm_resp.length, (unsigned long)gensec_ntlmssp_state->nt_resp.length));
 400
 401 #if 0
 402         file_save("nthash1.dat",  &gensec_ntlmssp_state->nt_resp.data,  &gensec_ntlmssp_state->nt_resp.length);
 403         file_save("lmhash1.dat",  &gensec_ntlmssp_state->lm_resp.data,  &gensec_ntlmssp_state->lm_resp.length);
 404 #endif
 405
 406         /* NTLM2 uses a 'challenge' that is made of up both the server challenge, and a
 407            client challenge
 408
 409            However, the NTLM2 flag may still be set for the real NTLMv2 logins, be careful.
 410         */
 411         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 412                 if (gensec_ntlmssp_state->nt_resp.length == 24 && gensec_ntlmssp_state->lm_resp.length == 24) {
 413                         struct MD5Context md5_session_nonce_ctx;
 414                         SMB_ASSERT(gensec_ntlmssp_state->internal_chal.data
 415                                    && gensec_ntlmssp_state->internal_chal.length == 8);
 416
 417                         gensec_ntlmssp_state->doing_ntlm2 = True;
 418
 419                         memcpy(gensec_ntlmssp_state->crypt.ntlm2.session_nonce, gensec_ntlmssp_state->internal_chal.data, 8);
 420                         memcpy(&gensec_ntlmssp_state->crypt.ntlm2.session_nonce[8], gensec_ntlmssp_state->lm_resp.data, 8);
 421
 422                         MD5Init(&md5_session_nonce_ctx);
 423                         MD5Update(&md5_session_nonce_ctx, gensec_ntlmssp_state->crypt.ntlm2.session_nonce, 16);
 424                         MD5Final(session_nonce_hash, &md5_session_nonce_ctx);
 425
 426                         gensec_ntlmssp_state->chal = data_blob_talloc(gensec_ntlmssp_state,
 427                                                                session_nonce_hash, 8);
 428
 429                         /* LM response is no longer useful, zero it out */
 430                         data_blob_free(&gensec_ntlmssp_state->lm_resp);
 431
 432                         /* We changed the effective challenge - set it */
 433                         if (!NT_STATUS_IS_OK(nt_status =
 434                                              gensec_ntlmssp_state->set_challenge(gensec_ntlmssp_state,
 435                                                                                  &gensec_ntlmssp_state->chal))) {
 436                                 /* zero this out */
 437                                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 438                                 return nt_status;
 439                         }
 440
 441                         /* LM Key is incompatible... */
 442                         gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 443                 }
 444         }
 445         return NT_STATUS_OK;
 446 }
 447
 448 /**
 449  * Next state function for the Authenticate packet
 450  * (after authentication - figures out the session keys etc)
 451  *
 452  * @param gensec_ntlmssp_state NTLMSSP State
 453  * @return Errors or NT_STATUS_OK.
 454  */
 455
 456 static NTSTATUS ntlmssp_server_postauth(struct gensec_security *gensec_security,
 457                                         DATA_BLOB *user_session_key,
 458                                         DATA_BLOB *lm_session_key)
 459 {
 460         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 461         NTSTATUS nt_status;
 462         DATA_BLOB session_key = data_blob(NULL, 0);
 463
 464         if (user_session_key)
 465                 dump_data_pw("USER session key:\n", user_session_key->data, user_session_key->length);
 466
 467         if (lm_session_key)
 468                 dump_data_pw("LM first-8:\n", lm_session_key->data, lm_session_key->length);
 469
 470         /* Handle the different session key derivation for NTLM2 */
 471         if (gensec_ntlmssp_state->doing_ntlm2) {
 472                 if (user_session_key && user_session_key->data && user_session_key->length == 16) {
 473                         session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 474                         hmac_md5(user_session_key->data, gensec_ntlmssp_state->crypt.ntlm2.session_nonce,
 475                                  sizeof(gensec_ntlmssp_state->crypt.ntlm2.session_nonce), session_key.data);
 476                         DEBUG(10,("ntlmssp_server_auth: Created NTLM2 session key.\n"));
 477                         dump_data_pw("NTLM2 session key:\n", session_key.data, session_key.length);
 478
 479                 } else {
 480                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM2 session key.\n"));
 481                         session_key = data_blob(NULL, 0);
 482                 }
 483         } else if ((gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 484                 /* Ensure we can never get here on NTLMv2 */
 485                 && (gensec_ntlmssp_state->nt_resp.length == 0 || gensec_ntlmssp_state->nt_resp.length == 24)) {
 486
 487                 if (lm_session_key && lm_session_key->data && lm_session_key->length >= 8) {
 488                         if (gensec_ntlmssp_state->lm_resp.data && gensec_ntlmssp_state->lm_resp.length == 24) {
 489                                 session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 490                                 SMBsesskeygen_lm_sess_key(lm_session_key->data, gensec_ntlmssp_state->lm_resp.data,
 491                                                           session_key.data);
 492                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 493                                 dump_data_pw("LM session key:\n", session_key.data, session_key.length);
 494                         } else {
 495
 496                                 /* When there is no LM response, just use zeros */
 497                                 static const uint8_t zeros[24];
 498                                 session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 499                                 SMBsesskeygen_lm_sess_key(zeros, zeros,
 500                                                           session_key.data);
 501                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 502                                 dump_data_pw("LM session key:\n", session_key.data, session_key.length);
 503                         }
 504                 } else {
 505                         /* LM Key not selected */
 506                         gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 507
 508                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM session key.\n"));
 509                         session_key = data_blob(NULL, 0);
 510                 }
 511
 512         } else if (user_session_key && user_session_key->data) {
 513                 session_key = *user_session_key;
 514                 DEBUG(10,("ntlmssp_server_auth: Using unmodified nt session key.\n"));
 515                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 516
 517                 /* LM Key not selected */
 518                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 519
 520         } else if (lm_session_key && lm_session_key->data) {
 521                 /* Very weird to have LM key, but no user session key, but anyway.. */
 522                 session_key = *lm_session_key;
 523                 DEBUG(10,("ntlmssp_server_auth: Using unmodified lm session key.\n"));
 524                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 525
 526                 /* LM Key not selected */
 527                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 528
 529         } else {
 530                 DEBUG(10,("ntlmssp_server_auth: Failed to create unmodified session key.\n"));
 531                 session_key = data_blob(NULL, 0);
 532
 533                 /* LM Key not selected */
 534                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 535         }
 536
 537         /* With KEY_EXCH, the client supplies the proposed session key,
 538            but encrypts it with the long-term key */
 539         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 540                 if (!gensec_ntlmssp_state->encrypted_session_key.data
 541                     || gensec_ntlmssp_state->encrypted_session_key.length != 16) {
 542                         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 543                         DEBUG(1, ("Client-supplied KEY_EXCH session key was of invalid length (%u)!\n",
 544                                   (unsigned)gensec_ntlmssp_state->encrypted_session_key.length));
 545                         return NT_STATUS_INVALID_PARAMETER;
 546                 } else if (!session_key.data || session_key.length != 16) {
 547                         DEBUG(5, ("server session key is invalid (len == %u), cannot do KEY_EXCH!\n",
 548                                   (unsigned)session_key.length));
 549                         gensec_ntlmssp_state->session_key = session_key;
 550                 } else {
 551                         dump_data_pw("KEY_EXCH session key (enc):\n",
 552                                      gensec_ntlmssp_state->encrypted_session_key.data,
 553                                      gensec_ntlmssp_state->encrypted_session_key.length);
 554                         arcfour_crypt(gensec_ntlmssp_state->encrypted_session_key.data,
 555                                       session_key.data,
 556                                       gensec_ntlmssp_state->encrypted_session_key.length);
 557                         gensec_ntlmssp_state->session_key = data_blob_talloc(gensec_ntlmssp_state,
 558                                                                       gensec_ntlmssp_state->encrypted_session_key.data,
 559                                                                       gensec_ntlmssp_state->encrypted_session_key.length);
 560                         dump_data_pw("KEY_EXCH session key:\n", gensec_ntlmssp_state->encrypted_session_key.data,
 561                                      gensec_ntlmssp_state->encrypted_session_key.length);
 562                 }
 563         } else {
 564                 gensec_ntlmssp_state->session_key = session_key;
 565         }
 566
 567         /* The server might need us to use a partial-strength session key */
 568         ntlmssp_weaken_keys(gensec_ntlmssp_state);
 569
 570         if ((gensec_security->want_features & GENSEC_FEATURE_SIGN)
 571             || (gensec_security->want_features & GENSEC_FEATURE_SEAL)) {
 572                 nt_status = ntlmssp_sign_init(gensec_ntlmssp_state);
 573         } else {
 574                 nt_status = NT_STATUS_OK;
 575         }
 576
 577         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 578
 579         /* allow arbitarily many authentications, but watch that this will cause a
 580            memory leak, until the gensec_ntlmssp_state is shutdown
 581         */
 582
 583         if (gensec_ntlmssp_state->server_multiple_authentications) {
 584                 gensec_ntlmssp_state->expected_state = NTLMSSP_AUTH;
 585         } else {
 586                 gensec_ntlmssp_state->expected_state = NTLMSSP_DONE;
 587         }
 588
 589         return nt_status;
 590 }
 591
 592
 593 /**
 594  * Next state function for the Authenticate packet
 595  *
 596  * @param gensec_security GENSEC state
 597  * @param out_mem_ctx Memory context for *out
 598  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
 599  * @param out The reply, as an allocated DATA_BLOB, caller to free.
 600  * @return Errors or NT_STATUS_OK if authentication sucessful
 601  */
 602
 603 NTSTATUS ntlmssp_server_auth(struct gensec_security *gensec_security,
 604                              TALLOC_CTX *out_mem_ctx,
 605                              const DATA_BLOB in, DATA_BLOB *out)
 606 {
 607         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 608         DATA_BLOB user_session_key = data_blob(NULL, 0);
 609         DATA_BLOB lm_session_key = data_blob(NULL, 0);
 610         NTSTATUS nt_status;
 611
 612         /* zero the outbound NTLMSSP packet */
 613         *out = data_blob_talloc(out_mem_ctx, NULL, 0);
 614
 615         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_server_preauth(gensec_ntlmssp_state, in))) {
 616                 return nt_status;
 617         }
 618
 619         /*
 620          * Note we don't check here for NTLMv2 auth settings. If NTLMv2 auth
 621          * is required (by "ntlm auth = no" and "lm auth = no" being set in the
 622          * smb.conf file) and no NTLMv2 response was sent then the password check
 623          * will fail here. JRA.
 624          */
 625
 626         /* Finally, actually ask if the password is OK */
 627
 628         if (!NT_STATUS_IS_OK(nt_status = gensec_ntlmssp_state->check_password(gensec_ntlmssp_state,
 629                                                                               &user_session_key, &lm_session_key))) {
 630                 return nt_status;
 631         }
 632
 633         if (gensec_security->want_features
 634             & (GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL|GENSEC_FEATURE_SESSION_KEY)) {
 635                 return ntlmssp_server_postauth(gensec_security, &user_session_key, &lm_session_key);
 636         } else {
 637                 gensec_ntlmssp_state->session_key = data_blob(NULL, 0);
 638                 return NT_STATUS_OK;
 639         }
 640 }
 641
 642 /**
 643  * Return the challenge as determined by the authentication subsystem
 644  * @return an 8 byte random challenge
 645  */
 646
 647 static const uint8_t *auth_ntlmssp_get_challenge(const struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 648 {
 649         NTSTATUS status;
 650         const uint8_t *chal;
 651
 652         status = auth_get_challenge(gensec_ntlmssp_state->auth_context, &chal);
 653         if (!NT_STATUS_IS_OK(status)) {
 654                 return NULL;
 655         }
 656
 657         return chal;
 658 }
 659
 660 /**
 661  * Some authentication methods 'fix' the challenge, so we may not be able to set it
 662  *
 663  * @return If the effective challenge used by the auth subsystem may be modified
 664  */
 665 static BOOL auth_ntlmssp_may_set_challenge(const struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 666 {
 667         return auth_challenge_may_be_modified(gensec_ntlmssp_state->auth_context);
 668 }
 669
 670 /**
 671  * NTLM2 authentication modifies the effective challenge,
 672  * @param challenge The new challenge value
 673  */
 674 static NTSTATUS auth_ntlmssp_set_challenge(struct gensec_ntlmssp_state *gensec_ntlmssp_state, DATA_BLOB *challenge)
 675 {
 676         NTSTATUS nt_status;
 677         struct auth_context *auth_context = gensec_ntlmssp_state->auth_context;
 678         const uint8_t *chal;
 679
 680         if (challenge->length != 8) {
 681                 return NT_STATUS_INVALID_PARAMETER;
 682         }
 683
 684         chal = challenge->data;
 685
 686         nt_status = auth_context_set_challenge(auth_context, chal, "NTLMSSP callback (NTLM2)");
 687
 688         return nt_status;
 689 }
 690
 691 /**
 692  * Check the password on an NTLMSSP login.
 693  *
 694  * Return the session keys used on the connection.
 695  */
 696
 697 static NTSTATUS auth_ntlmssp_check_password(struct gensec_ntlmssp_state *gensec_ntlmssp_state, DATA_BLOB *user_session_key, DATA_BLOB *lm_session_key)
 698 {
 699         NTSTATUS nt_status;
 700         struct auth_usersupplied_info *user_info = talloc(gensec_ntlmssp_state, struct auth_usersupplied_info);
 701         if (!user_info) {
 702                 return NT_STATUS_NO_MEMORY;
 703         }
 704
 705         user_info->flags = 0;
 706         user_info->mapped_state = False;
 707         user_info->client.account_name = gensec_ntlmssp_state->user;
 708         user_info->client.domain_name = gensec_ntlmssp_state->domain;
 709         user_info->workstation_name = gensec_ntlmssp_state->workstation;
 710
 711         user_info->password_state = AUTH_PASSWORD_RESPONSE;
 712         user_info->password.response.lanman = gensec_ntlmssp_state->lm_resp;
 713         user_info->password.response.lanman.data = talloc_steal(user_info, gensec_ntlmssp_state->lm_resp.data);
 714         user_info->password.response.nt = gensec_ntlmssp_state->nt_resp;
 715         user_info->password.response.nt.data = talloc_steal(user_info, gensec_ntlmssp_state->nt_resp.data);
 716
 717         nt_status = auth_check_password(gensec_ntlmssp_state->auth_context, gensec_ntlmssp_state,
 718                                         user_info, &gensec_ntlmssp_state->server_info);
 719         talloc_free(user_info);
 720         NT_STATUS_NOT_OK_RETURN(nt_status);
 721
 722         if (gensec_ntlmssp_state->server_info->user_session_key.length) {
 723                 DEBUG(10, ("Got NT session key of length %u\n",
 724                            (unsigned)gensec_ntlmssp_state->server_info->user_session_key.length));
 725                 *user_session_key = data_blob_talloc(gensec_ntlmssp_state,
 726                                                    gensec_ntlmssp_state->server_info->user_session_key.data,
 727                                                    gensec_ntlmssp_state->server_info->user_session_key.length);
 728         }
 729         if (gensec_ntlmssp_state->server_info->lm_session_key.length) {
 730                 DEBUG(10, ("Got LM session key of length %u\n",
 731                            (unsigned)gensec_ntlmssp_state->server_info->lm_session_key.length));
 732                 *lm_session_key = data_blob_talloc(gensec_ntlmssp_state,
 733                                                    gensec_ntlmssp_state->server_info->lm_session_key.data,
 734                                                    gensec_ntlmssp_state->server_info->lm_session_key.length);
 735         }
 736         return nt_status;
 737 }
 738
 739 /**
 740  * Return the credentials of a logged on user, including session keys
 741  * etc.
 742  *
 743  * Only valid after a successful authentication
 744  *
 745  * May only be called once per authentication.
 746  *
 747  */
 748
 749 NTSTATUS gensec_ntlmssp_session_info(struct gensec_security *gensec_security,
 750                                      struct auth_session_info **session_info)
 751 {
 752         NTSTATUS nt_status;
 753         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 754
 755         nt_status = auth_generate_session_info(gensec_ntlmssp_state, gensec_ntlmssp_state->server_info, session_info);
 756         NT_STATUS_NOT_OK_RETURN(nt_status);
 757
 758         (*session_info)->session_key = data_blob_talloc(*session_info,
 759                                                         gensec_ntlmssp_state->session_key.data,
 760                                                         gensec_ntlmssp_state->session_key.length);
 761
 762         return NT_STATUS_OK;
 763 }
 764
 765 /**
 766  * Start NTLMSSP on the server side
 767  *
 768  */
 769 NTSTATUS gensec_ntlmssp_server_start(struct gensec_security *gensec_security)
 770 {
 771         NTSTATUS nt_status;
 772         struct gensec_ntlmssp_state *gensec_ntlmssp_state;
 773
 774         nt_status = gensec_ntlmssp_start(gensec_security);
 775         NT_STATUS_NOT_OK_RETURN(nt_status);
 776
 777         gensec_ntlmssp_state = gensec_security->private_data;
 778
 779         gensec_ntlmssp_state->role = NTLMSSP_SERVER;
 780
 781         gensec_ntlmssp_state->workstation = NULL;
 782         gensec_ntlmssp_state->server_name = lp_netbios_name();
 783
 784         gensec_ntlmssp_state->get_domain = lp_workgroup;
 785
 786         gensec_ntlmssp_state->expected_state = NTLMSSP_NEGOTIATE;
 787
 788         gensec_ntlmssp_state->allow_lm_key = (lp_lanman_auth()
 789                                           && lp_parm_bool(-1, "ntlmssp_server", "allow_lm_key", False));
 790
 791         gensec_ntlmssp_state->server_multiple_authentications = False;
 792
 793         gensec_ntlmssp_state->neg_flags =
 794                 NTLMSSP_NEGOTIATE_NTLM;
 795
 796         gensec_ntlmssp_state->lm_resp = data_blob(NULL, 0);
 797         gensec_ntlmssp_state->nt_resp = data_blob(NULL, 0);
 798         gensec_ntlmssp_state->encrypted_session_key = data_blob(NULL, 0);
 799
 800         if (lp_parm_bool(-1, "ntlmssp_server", "128bit", True)) {
 801                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_128;
 802         }
 803
 804         if (lp_parm_bool(-1, "ntlmssp_server", "keyexchange", True)) {
 805                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_KEY_EXCH;
 806         }
 807
 808         if (lp_parm_bool(-1, "ntlmssp_server", "ntlm2", True)) {
 809                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
 810         }
 811
 812         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 813                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 814         }
 815         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 816                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 817         }
 818
 819         nt_status = auth_context_create(gensec_ntlmssp_state, lp_auth_methods(),
 820                                         &gensec_ntlmssp_state->auth_context,
 821                                         gensec_security->event_ctx);
 822         NT_STATUS_NOT_OK_RETURN(nt_status);
 823
 824         gensec_ntlmssp_state->get_challenge = auth_ntlmssp_get_challenge;
 825         gensec_ntlmssp_state->may_set_challenge = auth_ntlmssp_may_set_challenge;
 826         gensec_ntlmssp_state->set_challenge = auth_ntlmssp_set_challenge;
 827         gensec_ntlmssp_state->check_password = auth_ntlmssp_check_password;
 828         gensec_ntlmssp_state->server_role = lp_server_role();
 829
 830         return NT_STATUS_OK;
 831 }
 832