source4/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 "auth/ntlmssp/msrpc_parse.h"
  29 #include "lib/crypto/crypto.h"
  30 #include "pstring.h"
  31 #include "system/filesys.h"
  32 #include "libcli/auth/libcli_auth.h"
  33
  34 /**
  35  * Set a username on an NTLMSSP context - ensures it is talloc()ed
  36  *
  37  */
  38
  39 static NTSTATUS ntlmssp_set_username(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *user)
  40 {
  41         if (!user) {
  42                 /* it should be at least "" */
  43                 DEBUG(1, ("NTLMSSP failed to set username - cannot accept NULL username\n"));
  44                 return NT_STATUS_INVALID_PARAMETER;
  45         }
  46         gensec_ntlmssp_state->user = talloc_strdup(gensec_ntlmssp_state, user);
  47         if (!gensec_ntlmssp_state->user) {
  48                 return NT_STATUS_NO_MEMORY;
  49         }
  50         return NT_STATUS_OK;
  51 }
  52
  53 /**
  54  * Set a domain on an NTLMSSP context - ensures it is talloc()ed
  55  *
  56  */
  57 static NTSTATUS ntlmssp_set_domain(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *domain)
  58 {
  59         gensec_ntlmssp_state->domain = talloc_strdup(gensec_ntlmssp_state, domain);
  60         if (!gensec_ntlmssp_state->domain) {
  61                 return NT_STATUS_NO_MEMORY;
  62         }
  63         return NT_STATUS_OK;
  64 }
  65
  66 /**
  67  * Set a workstation on an NTLMSSP context - ensures it is talloc()ed
  68  *
  69  */
  70 static NTSTATUS ntlmssp_set_workstation(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *workstation)
  71 {
  72         gensec_ntlmssp_state->workstation = talloc_strdup(gensec_ntlmssp_state, workstation);
  73         if (!gensec_ntlmssp_state->workstation) {
  74                 return NT_STATUS_NO_MEMORY;
  75         }
  76         return NT_STATUS_OK;
  77 }
  78
  79 /**
  80  * Determine correct target name flags for reply, given server role
  81  * and negotiated flags
  82  *
  83  * @param gensec_ntlmssp_state NTLMSSP State
  84  * @param neg_flags The flags from the packet
  85  * @param chal_flags The flags to be set in the reply packet
  86  * @return The 'target name' string.
  87  */
  88
  89 static const char *ntlmssp_target_name(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
  90                                        uint32_t neg_flags, uint32_t *chal_flags)
  91 {
  92         if (neg_flags & NTLMSSP_REQUEST_TARGET) {
  93                 *chal_flags |= NTLMSSP_CHAL_TARGET_INFO;
  94                 *chal_flags |= NTLMSSP_REQUEST_TARGET;
  95                 if (gensec_ntlmssp_state->server_role == ROLE_STANDALONE) {
  96                         *chal_flags |= NTLMSSP_TARGET_TYPE_SERVER;
  97                         return gensec_ntlmssp_state->server_name;
  98                 } else {
  99                         *chal_flags |= NTLMSSP_TARGET_TYPE_DOMAIN;
 100                         return gensec_ntlmssp_state->get_domain();
 101                 };
 102         } else {
 103                 return "";
 104         }
 105 }
 106
 107 /*
 108   Andrew, please remove these totally bogus calls when you get time
 109 */
 110 static BOOL get_myfullname(char *my_name)
 111 {
 112         pstring hostname;
 113
 114         *hostname = 0;
 115
 116         /* get my host name */
 117         if (gethostname(hostname, sizeof(hostname)) == -1) {
 118                 DEBUG(0,("gethostname failed\n"));
 119                 return False;
 120         }
 121
 122         /* Ensure null termination. */
 123         hostname[sizeof(hostname)-1] = '\0';
 124
 125         if (my_name)
 126                 fstrcpy(my_name, hostname);
 127         return True;
 128 }
 129
 130 static BOOL get_mydomname(char *my_domname)
 131 {
 132         pstring hostname;
 133         char *p;
 134
 135         /* arrgh! relies on full name in system */
 136
 137         *hostname = 0;
 138         /* get my host name */
 139         if (gethostname(hostname, sizeof(hostname)) == -1) {
 140                 DEBUG(0,("gethostname failed\n"));
 141                 return False;
 142         }
 143
 144         /* Ensure null termination. */
 145         hostname[sizeof(hostname)-1] = '\0';
 146
 147         p = strchr_m(hostname, '.');
 148
 149         if (!p)
 150                 return False;
 151
 152         p++;
 153
 154         if (my_domname)
 155                 fstrcpy(my_domname, p);
 156
 157         return True;
 158 }
 159
 160
 161
 162 /**
 163  * Next state function for the Negotiate packet
 164  *
 165  * @param gensec_security GENSEC state
 166  * @param out_mem_ctx Memory context for *out
 167  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
 168  * @param out The reply, as an allocated DATA_BLOB, caller to free.
 169  * @return Errors or MORE_PROCESSING_REQUIRED if (normal) a reply is required.
 170  */
 171
 172 NTSTATUS ntlmssp_server_negotiate(struct gensec_security *gensec_security,
 173                                   TALLOC_CTX *out_mem_ctx,
 174                                   const DATA_BLOB in, DATA_BLOB *out)
 175 {
 176         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 177         DATA_BLOB struct_blob;
 178         fstring dnsname, dnsdomname;
 179         uint32_t neg_flags = 0;
 180         uint32_t ntlmssp_command, chal_flags;
 181         const uint8_t *cryptkey;
 182         const char *target_name;
 183
 184         /* parse the NTLMSSP packet */
 185 #if 0
 186         file_save("ntlmssp_negotiate.dat", request.data, request.length);
 187 #endif
 188
 189         if (in.length) {
 190                 if ((in.length < 16) || !msrpc_parse(out_mem_ctx, &in, "Cdd",
 191                                                          "NTLMSSP",
 192                                                          &ntlmssp_command,
 193                                                          &neg_flags)) {
 194                         DEBUG(1, ("ntlmssp_server_negotiate: failed to parse "
 195                                 "NTLMSSP Negotiate of length %u:\n",
 196                                 (unsigned int)in.length ));
 197                         dump_data(2, in.data, in.length);
 198                         return NT_STATUS_INVALID_PARAMETER;
 199                 }
 200                 debug_ntlmssp_flags(neg_flags);
 201         }
 202
 203         ntlmssp_handle_neg_flags(gensec_ntlmssp_state, neg_flags, gensec_ntlmssp_state->allow_lm_key);
 204
 205         /* Ask our caller what challenge they would like in the packet */
 206         cryptkey = gensec_ntlmssp_state->get_challenge(gensec_ntlmssp_state);
 207
 208         /* Check if we may set the challenge */
 209         if (!gensec_ntlmssp_state->may_set_challenge(gensec_ntlmssp_state)) {
 210                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
 211         }
 212
 213         /* The flags we send back are not just the negotiated flags,
 214          * they are also 'what is in this packet'.  Therfore, we
 215          * operate on 'chal_flags' from here on
 216          */
 217
 218         chal_flags = gensec_ntlmssp_state->neg_flags;
 219
 220         /* get the right name to fill in as 'target' */
 221         target_name = ntlmssp_target_name(gensec_ntlmssp_state,
 222                                           neg_flags, &chal_flags);
 223         if (target_name == NULL)
 224                 return NT_STATUS_INVALID_PARAMETER;
 225
 226         gensec_ntlmssp_state->chal = data_blob_talloc(gensec_ntlmssp_state, cryptkey, 8);
 227         gensec_ntlmssp_state->internal_chal = data_blob_talloc(gensec_ntlmssp_state, cryptkey, 8);
 228
 229         /* This should be a 'netbios domain -> DNS domain' mapping */
 230         dnsdomname[0] = '\0';
 231         get_mydomname(dnsdomname);
 232         strlower_m(dnsdomname);
 233
 234         dnsname[0] = '\0';
 235         get_myfullname(dnsname);
 236
 237         /* This creates the 'blob' of names that appears at the end of the packet */
 238         if (chal_flags & NTLMSSP_CHAL_TARGET_INFO)
 239         {
 240                 const char *target_name_dns = "";
 241                 if (chal_flags |= NTLMSSP_TARGET_TYPE_DOMAIN) {
 242                         target_name_dns = dnsdomname;
 243                 } else if (chal_flags |= NTLMSSP_TARGET_TYPE_SERVER) {
 244                         target_name_dns = dnsname;
 245                 }
 246
 247                 msrpc_gen(out_mem_ctx,
 248                           &struct_blob, "aaaaa",
 249                           NTLMSSP_NAME_TYPE_DOMAIN, target_name,
 250                           NTLMSSP_NAME_TYPE_SERVER, gensec_ntlmssp_state->server_name,
 251                           NTLMSSP_NAME_TYPE_DOMAIN_DNS, dnsdomname,
 252                           NTLMSSP_NAME_TYPE_SERVER_DNS, dnsname,
 253                           0, "");
 254         } else {
 255                 struct_blob = data_blob(NULL, 0);
 256         }
 257
 258         {
 259                 /* Marshel the packet in the right format, be it unicode or ASCII */
 260                 const char *gen_string;
 261                 if (gensec_ntlmssp_state->unicode) {
 262                         gen_string = "CdUdbddB";
 263                 } else {
 264                         gen_string = "CdAdbddB";
 265                 }
 266
 267                 msrpc_gen(out_mem_ctx,
 268                           out, gen_string,
 269                           "NTLMSSP",
 270                           NTLMSSP_CHALLENGE,
 271                           target_name,
 272                           chal_flags,
 273                           cryptkey, 8,
 274                           0, 0,
 275                           struct_blob.data, struct_blob.length);
 276         }
 277
 278         gensec_ntlmssp_state->expected_state = NTLMSSP_AUTH;
 279
 280         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 281 }
 282
 283 /**
 284  * Next state function for the Authenticate packet
 285  *
 286  * @param gensec_ntlmssp_state NTLMSSP State
 287  * @param request The request, as a DATA_BLOB
 288  * @return Errors or NT_STATUS_OK.
 289  */
 290
 291 static NTSTATUS ntlmssp_server_preauth(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
 292                                        const DATA_BLOB request)
 293 {
 294         uint32_t ntlmssp_command, auth_flags;
 295         NTSTATUS nt_status;
 296
 297         uint8_t session_nonce_hash[16];
 298
 299         const char *parse_string;
 300         char *domain = NULL;
 301         char *user = NULL;
 302         char *workstation = NULL;
 303
 304 #if 0
 305         file_save("ntlmssp_auth.dat", request.data, request.length);
 306 #endif
 307
 308         if (gensec_ntlmssp_state->unicode) {
 309                 parse_string = "CdBBUUUBd";
 310         } else {
 311                 parse_string = "CdBBAAABd";
 312         }
 313
 314         /* zero these out */
 315         data_blob_free(&gensec_ntlmssp_state->lm_resp);
 316         data_blob_free(&gensec_ntlmssp_state->nt_resp);
 317         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 318
 319         gensec_ntlmssp_state->user = NULL;
 320         gensec_ntlmssp_state->domain = NULL;
 321         gensec_ntlmssp_state->workstation = NULL;
 322
 323         /* now the NTLMSSP encoded auth hashes */
 324         if (!msrpc_parse(gensec_ntlmssp_state,
 325                          &request, parse_string,
 326                          "NTLMSSP",
 327                          &ntlmssp_command,
 328                          &gensec_ntlmssp_state->lm_resp,
 329                          &gensec_ntlmssp_state->nt_resp,
 330                          &domain,
 331                          &user,
 332                          &workstation,
 333                          &gensec_ntlmssp_state->encrypted_session_key,
 334                          &auth_flags)) {
 335                 DEBUG(10, ("ntlmssp_server_auth: failed to parse NTLMSSP (nonfatal):\n"));
 336                 dump_data(10, request.data, request.length);
 337
 338                 /* zero this out */
 339                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 340                 auth_flags = 0;
 341
 342                 /* Try again with a shorter string (Win9X truncates this packet) */
 343                 if (gensec_ntlmssp_state->unicode) {
 344                         parse_string = "CdBBUUU";
 345                 } else {
 346                         parse_string = "CdBBAAA";
 347                 }
 348
 349                 /* now the NTLMSSP encoded auth hashes */
 350                 if (!msrpc_parse(gensec_ntlmssp_state,
 351                                  &request, parse_string,
 352                                  "NTLMSSP",
 353                                  &ntlmssp_command,
 354                                  &gensec_ntlmssp_state->lm_resp,
 355                                  &gensec_ntlmssp_state->nt_resp,
 356                                  &domain,
 357                                  &user,
 358                                  &workstation)) {
 359                         DEBUG(1, ("ntlmssp_server_auth: failed to parse NTLMSSP:\n"));
 360                         dump_data(2, request.data, request.length);
 361
 362                         return NT_STATUS_INVALID_PARAMETER;
 363                 }
 364         }
 365
 366         if (auth_flags)
 367                 ntlmssp_handle_neg_flags(gensec_ntlmssp_state, auth_flags, gensec_ntlmssp_state->allow_lm_key);
 368
 369         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_domain(gensec_ntlmssp_state, domain))) {
 370                 /* zero this out */
 371                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 372                 return nt_status;
 373         }
 374
 375         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_username(gensec_ntlmssp_state, user))) {
 376                 /* zero this out */
 377                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 378                 return nt_status;
 379         }
 380
 381         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_workstation(gensec_ntlmssp_state, workstation))) {
 382                 /* zero this out */
 383                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 384                 return nt_status;
 385         }
 386
 387         DEBUG(3,("Got user=[%s] domain=[%s] workstation=[%s] len1=%lu len2=%lu\n",
 388                  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));
 389
 390 #if 0
 391         file_save("nthash1.dat",  &gensec_ntlmssp_state->nt_resp.data,  &gensec_ntlmssp_state->nt_resp.length);
 392         file_save("lmhash1.dat",  &gensec_ntlmssp_state->lm_resp.data,  &gensec_ntlmssp_state->lm_resp.length);
 393 #endif
 394
 395         /* NTLM2 uses a 'challenge' that is made of up both the server challenge, and a
 396            client challenge
 397
 398            However, the NTLM2 flag may still be set for the real NTLMv2 logins, be careful.
 399         */
 400         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 401                 if (gensec_ntlmssp_state->nt_resp.length == 24 && gensec_ntlmssp_state->lm_resp.length == 24) {
 402                         struct MD5Context md5_session_nonce_ctx;
 403                         SMB_ASSERT(gensec_ntlmssp_state->internal_chal.data
 404                                    && gensec_ntlmssp_state->internal_chal.length == 8);
 405
 406                         gensec_ntlmssp_state->doing_ntlm2 = True;
 407
 408                         memcpy(gensec_ntlmssp_state->crypt.ntlm2.session_nonce, gensec_ntlmssp_state->internal_chal.data, 8);
 409                         memcpy(&gensec_ntlmssp_state->crypt.ntlm2.session_nonce[8], gensec_ntlmssp_state->lm_resp.data, 8);
 410
 411                         MD5Init(&md5_session_nonce_ctx);
 412                         MD5Update(&md5_session_nonce_ctx, gensec_ntlmssp_state->crypt.ntlm2.session_nonce, 16);
 413                         MD5Final(session_nonce_hash, &md5_session_nonce_ctx);
 414
 415                         gensec_ntlmssp_state->chal = data_blob_talloc(gensec_ntlmssp_state,
 416                                                                session_nonce_hash, 8);
 417
 418                         /* LM response is no longer useful, zero it out */
 419                         data_blob_free(&gensec_ntlmssp_state->lm_resp);
 420
 421                         /* We changed the effective challenge - set it */
 422                         if (!NT_STATUS_IS_OK(nt_status =
 423                                              gensec_ntlmssp_state->set_challenge(gensec_ntlmssp_state,
 424                                                                                  &gensec_ntlmssp_state->chal))) {
 425                                 /* zero this out */
 426                                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 427                                 return nt_status;
 428                         }
 429
 430                         /* LM Key is incompatible... */
 431                         gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 432                 }
 433         }
 434         return NT_STATUS_OK;
 435 }
 436
 437 /**
 438  * Next state function for the Authenticate packet
 439  * (after authentication - figures out the session keys etc)
 440  *
 441  * @param gensec_ntlmssp_state NTLMSSP State
 442  * @return Errors or NT_STATUS_OK.
 443  */
 444
 445 static NTSTATUS ntlmssp_server_postauth(struct gensec_security *gensec_security,
 446                                         DATA_BLOB *user_session_key,
 447                                         DATA_BLOB *lm_session_key)
 448 {
 449         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 450         NTSTATUS nt_status;
 451         DATA_BLOB session_key = data_blob(NULL, 0);
 452
 453         if (user_session_key)
 454                 dump_data_pw("USER session key:\n", user_session_key->data, user_session_key->length);
 455
 456         if (lm_session_key)
 457                 dump_data_pw("LM first-8:\n", lm_session_key->data, lm_session_key->length);
 458
 459         /* Handle the different session key derivation for NTLM2 */
 460         if (gensec_ntlmssp_state->doing_ntlm2) {
 461                 if (user_session_key && user_session_key->data && user_session_key->length == 16) {
 462                         session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 463                         hmac_md5(user_session_key->data, gensec_ntlmssp_state->crypt.ntlm2.session_nonce,
 464                                  sizeof(gensec_ntlmssp_state->crypt.ntlm2.session_nonce), session_key.data);
 465                         DEBUG(10,("ntlmssp_server_auth: Created NTLM2 session key.\n"));
 466                         dump_data_pw("NTLM2 session key:\n", session_key.data, session_key.length);
 467
 468                 } else {
 469                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM2 session key.\n"));
 470                         session_key = data_blob(NULL, 0);
 471                 }
 472         } else if ((gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 473                 /* Ensure we can never get here on NTLMv2 */
 474                 && (gensec_ntlmssp_state->nt_resp.length == 0 || gensec_ntlmssp_state->nt_resp.length == 24)) {
 475
 476                 if (lm_session_key && lm_session_key->data && lm_session_key->length >= 8) {
 477                         if (gensec_ntlmssp_state->lm_resp.data && gensec_ntlmssp_state->lm_resp.length == 24) {
 478                                 session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 479                                 SMBsesskeygen_lm_sess_key(lm_session_key->data, gensec_ntlmssp_state->lm_resp.data,
 480                                                           session_key.data);
 481                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 482                                 dump_data_pw("LM session key:\n", session_key.data, session_key.length);
 483                         } else {
 484
 485                                 /* When there is no LM response, just use zeros */
 486                                 static const uint8_t zeros[24];
 487                                 session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 488                                 SMBsesskeygen_lm_sess_key(zeros, zeros,
 489                                                           session_key.data);
 490                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 491                                 dump_data_pw("LM session key:\n", session_key.data, session_key.length);
 492                         }
 493                 } else {
 494                         /* LM Key not selected */
 495                         gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 496
 497                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM session key.\n"));
 498                         session_key = data_blob(NULL, 0);
 499                 }
 500
 501         } else if (user_session_key && user_session_key->data) {
 502                 session_key = *user_session_key;
 503                 DEBUG(10,("ntlmssp_server_auth: Using unmodified nt session key.\n"));
 504                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 505
 506                 /* LM Key not selected */
 507                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 508
 509         } else if (lm_session_key && lm_session_key->data) {
 510                 /* Very weird to have LM key, but no user session key, but anyway.. */
 511                 session_key = *lm_session_key;
 512                 DEBUG(10,("ntlmssp_server_auth: Using unmodified lm session key.\n"));
 513                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 514
 515                 /* LM Key not selected */
 516                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 517
 518         } else {
 519                 DEBUG(10,("ntlmssp_server_auth: Failed to create unmodified session key.\n"));
 520                 session_key = data_blob(NULL, 0);
 521
 522                 /* LM Key not selected */
 523                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 524         }
 525
 526         /* With KEY_EXCH, the client supplies the proposed session key,
 527            but encrypts it with the long-term key */
 528         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 529                 if (!gensec_ntlmssp_state->encrypted_session_key.data
 530                     || gensec_ntlmssp_state->encrypted_session_key.length != 16) {
 531                         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 532                         DEBUG(1, ("Client-supplied KEY_EXCH session key was of invalid length (%u)!\n",
 533                                   (unsigned)gensec_ntlmssp_state->encrypted_session_key.length));
 534                         return NT_STATUS_INVALID_PARAMETER;
 535                 } else if (!session_key.data || session_key.length != 16) {
 536                         DEBUG(5, ("server session key is invalid (len == %u), cannot do KEY_EXCH!\n",
 537                                   (unsigned)session_key.length));
 538                         gensec_ntlmssp_state->session_key = session_key;
 539                 } else {
 540                         dump_data_pw("KEY_EXCH session key (enc):\n",
 541                                      gensec_ntlmssp_state->encrypted_session_key.data,
 542                                      gensec_ntlmssp_state->encrypted_session_key.length);
 543                         arcfour_crypt(gensec_ntlmssp_state->encrypted_session_key.data,
 544                                       session_key.data,
 545                                       gensec_ntlmssp_state->encrypted_session_key.length);
 546                         gensec_ntlmssp_state->session_key = data_blob_talloc(gensec_ntlmssp_state,
 547                                                                       gensec_ntlmssp_state->encrypted_session_key.data,
 548                                                                       gensec_ntlmssp_state->encrypted_session_key.length);
 549                         dump_data_pw("KEY_EXCH session key:\n", gensec_ntlmssp_state->encrypted_session_key.data,
 550                                      gensec_ntlmssp_state->encrypted_session_key.length);
 551                 }
 552         } else {
 553                 gensec_ntlmssp_state->session_key = session_key;
 554         }
 555
 556         /* keep the session key around on the new context */
 557         talloc_steal(gensec_ntlmssp_state, session_key.data);
 558
 559         if ((gensec_security->want_features & GENSEC_FEATURE_SIGN)
 560             || (gensec_security->want_features & GENSEC_FEATURE_SEAL)) {
 561                 nt_status = ntlmssp_sign_init(gensec_ntlmssp_state);
 562         } else {
 563                 nt_status = NT_STATUS_OK;
 564         }
 565
 566         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 567
 568         /* allow arbitarily many authentications, but watch that this will cause a
 569            memory leak, until the gensec_ntlmssp_state is shutdown
 570         */
 571
 572         if (gensec_ntlmssp_state->server_multiple_authentications) {
 573                 gensec_ntlmssp_state->expected_state = NTLMSSP_AUTH;
 574         } else {
 575                 gensec_ntlmssp_state->expected_state = NTLMSSP_DONE;
 576         }
 577
 578         return nt_status;
 579 }
 580
 581
 582 /**
 583  * Next state function for the Authenticate packet
 584  *
 585  * @param gensec_security GENSEC state
 586  * @param out_mem_ctx Memory context for *out
 587  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
 588  * @param out The reply, as an allocated DATA_BLOB, caller to free.
 589  * @return Errors or NT_STATUS_OK if authentication sucessful
 590  */
 591
 592 NTSTATUS ntlmssp_server_auth(struct gensec_security *gensec_security,
 593                              TALLOC_CTX *out_mem_ctx,
 594                              const DATA_BLOB in, DATA_BLOB *out)
 595 {
 596         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 597         DATA_BLOB user_session_key = data_blob(NULL, 0);
 598         DATA_BLOB lm_session_key = data_blob(NULL, 0);
 599         NTSTATUS nt_status;
 600
 601         TALLOC_CTX *mem_ctx = talloc_new(out_mem_ctx);
 602         if (!mem_ctx) {
 603                 return NT_STATUS_NO_MEMORY;
 604         }
 605
 606         /* zero the outbound NTLMSSP packet */
 607         *out = data_blob_talloc(out_mem_ctx, NULL, 0);
 608
 609         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_server_preauth(gensec_ntlmssp_state, in))) {
 610                 talloc_free(mem_ctx);
 611                 return nt_status;
 612         }
 613
 614         /*
 615          * Note we don't check here for NTLMv2 auth settings. If NTLMv2 auth
 616          * is required (by "ntlm auth = no" and "lm auth = no" being set in the
 617          * smb.conf file) and no NTLMv2 response was sent then the password check
 618          * will fail here. JRA.
 619          */
 620
 621         /* Finally, actually ask if the password is OK */
 622
 623         if (!NT_STATUS_IS_OK(nt_status = gensec_ntlmssp_state->check_password(gensec_ntlmssp_state, mem_ctx,
 624                                                                               &user_session_key, &lm_session_key))) {
 625                 talloc_free(mem_ctx);
 626                 return nt_status;
 627         }
 628
 629         if (gensec_security->want_features
 630             & (GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL|GENSEC_FEATURE_SESSION_KEY)) {
 631                 nt_status = ntlmssp_server_postauth(gensec_security, &user_session_key, &lm_session_key);
 632                 talloc_free(mem_ctx);
 633                 return nt_status;
 634         } else {
 635                 gensec_ntlmssp_state->session_key = data_blob(NULL, 0);
 636                 talloc_free(mem_ctx);
 637                 return NT_STATUS_OK;
 638         }
 639 }
 640
 641 /**
 642  * Return the challenge as determined by the authentication subsystem
 643  * @return an 8 byte random challenge
 644  */
 645
 646 static const uint8_t *auth_ntlmssp_get_challenge(const struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 647 {
 648         NTSTATUS status;
 649         const uint8_t *chal;
 650
 651         status = auth_get_challenge(gensec_ntlmssp_state->auth_context, &chal);
 652         if (!NT_STATUS_IS_OK(status)) {
 653                 return NULL;
 654         }
 655
 656         return chal;
 657 }
 658
 659 /**
 660  * Some authentication methods 'fix' the challenge, so we may not be able to set it
 661  *
 662  * @return If the effective challenge used by the auth subsystem may be modified
 663  */
 664 static BOOL auth_ntlmssp_may_set_challenge(const struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 665 {
 666         return auth_challenge_may_be_modified(gensec_ntlmssp_state->auth_context);
 667 }
 668
 669 /**
 670  * NTLM2 authentication modifies the effective challenge,
 671  * @param challenge The new challenge value
 672  */
 673 static NTSTATUS auth_ntlmssp_set_challenge(struct gensec_ntlmssp_state *gensec_ntlmssp_state, DATA_BLOB *challenge)
 674 {
 675         NTSTATUS nt_status;
 676         struct auth_context *auth_context = gensec_ntlmssp_state->auth_context;
 677         const uint8_t *chal;
 678
 679         if (challenge->length != 8) {
 680                 return NT_STATUS_INVALID_PARAMETER;
 681         }
 682
 683         chal = challenge->data;
 684
 685         nt_status = auth_context_set_challenge(auth_context, chal, "NTLMSSP callback (NTLM2)");
 686
 687         return nt_status;
 688 }
 689
 690 /**
 691  * Check the password on an NTLMSSP login.
 692  *
 693  * Return the session keys used on the connection.
 694  */
 695
 696 static NTSTATUS auth_ntlmssp_check_password(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
 697                                             TALLOC_CTX *mem_ctx,
 698                                             DATA_BLOB *user_session_key, DATA_BLOB *lm_session_key)
 699 {
 700         NTSTATUS nt_status;
 701         struct auth_usersupplied_info *user_info = talloc(mem_ctx, struct auth_usersupplied_info);
 702         if (!user_info) {
 703                 return NT_STATUS_NO_MEMORY;
 704         }
 705
 706         user_info->logon_parameters = MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT | MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT;
 707         user_info->flags = 0;
 708         user_info->mapped_state = False;
 709         user_info->client.account_name = gensec_ntlmssp_state->user;
 710         user_info->client.domain_name = gensec_ntlmssp_state->domain;
 711         user_info->workstation_name = gensec_ntlmssp_state->workstation;
 712         user_info->remote_host = gensec_get_peer_addr(gensec_ntlmssp_state->gensec_security);
 713
 714         user_info->password_state = AUTH_PASSWORD_RESPONSE;
 715         user_info->password.response.lanman = gensec_ntlmssp_state->lm_resp;
 716         user_info->password.response.lanman.data = talloc_steal(user_info, gensec_ntlmssp_state->lm_resp.data);
 717         user_info->password.response.nt = gensec_ntlmssp_state->nt_resp;
 718         user_info->password.response.nt.data = talloc_steal(user_info, gensec_ntlmssp_state->nt_resp.data);
 719
 720         nt_status = auth_check_password(gensec_ntlmssp_state->auth_context, mem_ctx,
 721                                         user_info, &gensec_ntlmssp_state->server_info);
 722         talloc_free(user_info);
 723         NT_STATUS_NOT_OK_RETURN(nt_status);
 724
 725         talloc_steal(gensec_ntlmssp_state, gensec_ntlmssp_state->server_info);
 726
 727         if (gensec_ntlmssp_state->server_info->user_session_key.length) {
 728                 DEBUG(10, ("Got NT session key of length %u\n",
 729                            (unsigned)gensec_ntlmssp_state->server_info->user_session_key.length));
 730                 if (!talloc_reference(mem_ctx, gensec_ntlmssp_state->server_info->user_session_key.data)) {
 731                         return NT_STATUS_NO_MEMORY;
 732                 }
 733
 734                 *user_session_key = gensec_ntlmssp_state->server_info->user_session_key;
 735         }
 736         if (gensec_ntlmssp_state->server_info->lm_session_key.length) {
 737                 DEBUG(10, ("Got LM session key of length %u\n",
 738                            (unsigned)gensec_ntlmssp_state->server_info->lm_session_key.length));
 739                 if (!talloc_reference(mem_ctx, gensec_ntlmssp_state->server_info->lm_session_key.data)) {
 740                         return NT_STATUS_NO_MEMORY;
 741                 }
 742
 743                 *lm_session_key = gensec_ntlmssp_state->server_info->lm_session_key;
 744         }
 745         return nt_status;
 746 }
 747
 748 /**
 749  * Return the credentials of a logged on user, including session keys
 750  * etc.
 751  *
 752  * Only valid after a successful authentication
 753  *
 754  * May only be called once per authentication.
 755  *
 756  */
 757
 758 NTSTATUS gensec_ntlmssp_session_info(struct gensec_security *gensec_security,
 759                                      struct auth_session_info **session_info)
 760 {
 761         NTSTATUS nt_status;
 762         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 763
 764         nt_status = auth_generate_session_info(gensec_ntlmssp_state, gensec_ntlmssp_state->server_info, session_info);
 765         NT_STATUS_NOT_OK_RETURN(nt_status);
 766
 767         (*session_info)->session_key = data_blob_talloc(*session_info,
 768                                                         gensec_ntlmssp_state->session_key.data,
 769                                                         gensec_ntlmssp_state->session_key.length);
 770
 771         return NT_STATUS_OK;
 772 }
 773
 774 /**
 775  * Start NTLMSSP on the server side
 776  *
 777  */
 778 NTSTATUS gensec_ntlmssp_server_start(struct gensec_security *gensec_security)
 779 {
 780         NTSTATUS nt_status;
 781         struct gensec_ntlmssp_state *gensec_ntlmssp_state;
 782
 783         nt_status = gensec_ntlmssp_start(gensec_security);
 784         NT_STATUS_NOT_OK_RETURN(nt_status);
 785
 786         gensec_ntlmssp_state = gensec_security->private_data;
 787
 788         gensec_ntlmssp_state->role = NTLMSSP_SERVER;
 789
 790         gensec_ntlmssp_state->workstation = NULL;
 791         gensec_ntlmssp_state->server_name = lp_netbios_name();
 792
 793         gensec_ntlmssp_state->get_domain = lp_workgroup;
 794
 795         gensec_ntlmssp_state->expected_state = NTLMSSP_NEGOTIATE;
 796
 797         gensec_ntlmssp_state->allow_lm_key = (lp_lanman_auth()
 798                                           && lp_parm_bool(-1, "ntlmssp_server", "allow_lm_key", False));
 799
 800         gensec_ntlmssp_state->server_multiple_authentications = False;
 801
 802         gensec_ntlmssp_state->neg_flags =
 803                 NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_UNKNOWN_02000000;
 804
 805         gensec_ntlmssp_state->lm_resp = data_blob(NULL, 0);
 806         gensec_ntlmssp_state->nt_resp = data_blob(NULL, 0);
 807         gensec_ntlmssp_state->encrypted_session_key = data_blob(NULL, 0);
 808
 809         if (lp_parm_bool(-1, "ntlmssp_server", "128bit", True)) {
 810                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_128;
 811         }
 812
 813         if (lp_parm_bool(-1, "ntlmssp_server", "56bit", True)) {
 814                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
 815         }
 816
 817         if (lp_parm_bool(-1, "ntlmssp_server", "keyexchange", True)) {
 818                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_KEY_EXCH;
 819         }
 820
 821         if (lp_parm_bool(-1, "ntlmssp_server", "ntlm2", True)) {
 822                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
 823         }
 824
 825         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 826                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 827         }
 828         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 829                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 830         }
 831
 832         nt_status = auth_context_create(gensec_ntlmssp_state, lp_auth_methods(),
 833                                         gensec_security->event_ctx,
 834                                         gensec_security->msg_ctx,
 835                                         &gensec_ntlmssp_state->auth_context);
 836         NT_STATUS_NOT_OK_RETURN(nt_status);
 837
 838         gensec_ntlmssp_state->get_challenge = auth_ntlmssp_get_challenge;
 839         gensec_ntlmssp_state->may_set_challenge = auth_ntlmssp_may_set_challenge;
 840         gensec_ntlmssp_state->set_challenge = auth_ntlmssp_set_challenge;
 841         gensec_ntlmssp_state->check_password = auth_ntlmssp_check_password;
 842         gensec_ntlmssp_state->server_role = lp_server_role();
 843
 844         return NT_STATUS_OK;
 845 }
 846