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/ntlmssp/ntlmssp.h"
  27 #include "auth/ntlmssp/msrpc_parse.h"
  28 #include "lib/crypto/crypto.h"
  29 #include "pstring.h"
  30 #include "system/filesys.h"
  31 #include "libcli/auth/libcli_auth.h"
  32 #include "auth/credentials/credentials.h"
  33 #include "auth/gensec/gensec.h"
  34 #include "auth/auth.h"
  35
  36 /**
  37  * Set a username on an NTLMSSP context - ensures it is talloc()ed
  38  *
  39  */
  40
  41 static NTSTATUS ntlmssp_set_username(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *user)
  42 {
  43         if (!user) {
  44                 /* it should be at least "" */
  45                 DEBUG(1, ("NTLMSSP failed to set username - cannot accept NULL username\n"));
  46                 return NT_STATUS_INVALID_PARAMETER;
  47         }
  48         gensec_ntlmssp_state->user = talloc_strdup(gensec_ntlmssp_state, user);
  49         if (!gensec_ntlmssp_state->user) {
  50                 return NT_STATUS_NO_MEMORY;
  51         }
  52         return NT_STATUS_OK;
  53 }
  54
  55 /**
  56  * Set a domain on an NTLMSSP context - ensures it is talloc()ed
  57  *
  58  */
  59 static NTSTATUS ntlmssp_set_domain(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *domain)
  60 {
  61         gensec_ntlmssp_state->domain = talloc_strdup(gensec_ntlmssp_state, domain);
  62         if (!gensec_ntlmssp_state->domain) {
  63                 return NT_STATUS_NO_MEMORY;
  64         }
  65         return NT_STATUS_OK;
  66 }
  67
  68 /**
  69  * Set a workstation on an NTLMSSP context - ensures it is talloc()ed
  70  *
  71  */
  72 static NTSTATUS ntlmssp_set_workstation(struct gensec_ntlmssp_state *gensec_ntlmssp_state, const char *workstation)
  73 {
  74         gensec_ntlmssp_state->workstation = talloc_strdup(gensec_ntlmssp_state, workstation);
  75         if (!gensec_ntlmssp_state->workstation) {
  76                 return NT_STATUS_NO_MEMORY;
  77         }
  78         return NT_STATUS_OK;
  79 }
  80
  81 /**
  82  * Determine correct target name flags for reply, given server role
  83  * and negotiated flags
  84  *
  85  * @param gensec_ntlmssp_state NTLMSSP State
  86  * @param neg_flags The flags from the packet
  87  * @param chal_flags The flags to be set in the reply packet
  88  * @return The 'target name' string.
  89  */
  90
  91 static const char *ntlmssp_target_name(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
  92                                        uint32_t neg_flags, uint32_t *chal_flags)
  93 {
  94         if (neg_flags & NTLMSSP_REQUEST_TARGET) {
  95                 *chal_flags |= NTLMSSP_CHAL_TARGET_INFO;
  96                 *chal_flags |= NTLMSSP_REQUEST_TARGET;
  97                 if (gensec_ntlmssp_state->server_role == ROLE_STANDALONE) {
  98                         *chal_flags |= NTLMSSP_TARGET_TYPE_SERVER;
  99                         return gensec_ntlmssp_state->server_name;
 100                 } else {
 101                         *chal_flags |= NTLMSSP_TARGET_TYPE_DOMAIN;
 102                         return gensec_ntlmssp_state->get_domain();
 103                 };
 104         } else {
 105                 return "";
 106         }
 107 }
 108
 109 /*
 110   Andrew, please remove these totally bogus calls when you get time
 111 */
 112 static BOOL get_myfullname(char *my_name)
 113 {
 114         pstring hostname;
 115
 116         *hostname = 0;
 117
 118         /* get my host name */
 119         if (gethostname(hostname, sizeof(hostname)) == -1) {
 120                 DEBUG(0,("gethostname failed\n"));
 121                 return False;
 122         }
 123
 124         /* Ensure null termination. */
 125         hostname[sizeof(hostname)-1] = '\0';
 126
 127         if (my_name)
 128                 fstrcpy(my_name, hostname);
 129         return True;
 130 }
 131
 132 static BOOL get_mydomname(char *my_domname)
 133 {
 134         pstring hostname;
 135         char *p;
 136
 137         /* arrgh! relies on full name in system */
 138
 139         *hostname = 0;
 140         /* get my host name */
 141         if (gethostname(hostname, sizeof(hostname)) == -1) {
 142                 DEBUG(0,("gethostname failed\n"));
 143                 return False;
 144         }
 145
 146         /* Ensure null termination. */
 147         hostname[sizeof(hostname)-1] = '\0';
 148
 149         p = strchr_m(hostname, '.');
 150
 151         if (!p)
 152                 return False;
 153
 154         p++;
 155
 156         if (my_domname)
 157                 fstrcpy(my_domname, p);
 158
 159         return True;
 160 }
 161
 162
 163
 164 /**
 165  * Next state function for the Negotiate packet
 166  *
 167  * @param gensec_security GENSEC state
 168  * @param out_mem_ctx Memory context for *out
 169  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
 170  * @param out The reply, as an allocated DATA_BLOB, caller to free.
 171  * @return Errors or MORE_PROCESSING_REQUIRED if (normal) a reply is required.
 172  */
 173
 174 NTSTATUS ntlmssp_server_negotiate(struct gensec_security *gensec_security,
 175                                   TALLOC_CTX *out_mem_ctx,
 176                                   const DATA_BLOB in, DATA_BLOB *out)
 177 {
 178         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 179         DATA_BLOB struct_blob;
 180         fstring dnsname, dnsdomname;
 181         uint32_t neg_flags = 0;
 182         uint32_t ntlmssp_command, chal_flags;
 183         const uint8_t *cryptkey;
 184         const char *target_name;
 185
 186         /* parse the NTLMSSP packet */
 187 #if 0
 188         file_save("ntlmssp_negotiate.dat", request.data, request.length);
 189 #endif
 190
 191         if (in.length) {
 192                 if ((in.length < 16) || !msrpc_parse(out_mem_ctx, &in, "Cdd",
 193                                                          "NTLMSSP",
 194                                                          &ntlmssp_command,
 195                                                          &neg_flags)) {
 196                         DEBUG(1, ("ntlmssp_server_negotiate: failed to parse "
 197                                 "NTLMSSP Negotiate of length %u:\n",
 198                                 (unsigned int)in.length ));
 199                         dump_data(2, in.data, in.length);
 200                         return NT_STATUS_INVALID_PARAMETER;
 201                 }
 202                 debug_ntlmssp_flags(neg_flags);
 203         }
 204
 205         ntlmssp_handle_neg_flags(gensec_ntlmssp_state, neg_flags, gensec_ntlmssp_state->allow_lm_key);
 206
 207         /* Ask our caller what challenge they would like in the packet */
 208         cryptkey = gensec_ntlmssp_state->get_challenge(gensec_ntlmssp_state);
 209
 210         /* Check if we may set the challenge */
 211         if (!gensec_ntlmssp_state->may_set_challenge(gensec_ntlmssp_state)) {
 212                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
 213         }
 214
 215         /* The flags we send back are not just the negotiated flags,
 216          * they are also 'what is in this packet'.  Therfore, we
 217          * operate on 'chal_flags' from here on
 218          */
 219
 220         chal_flags = gensec_ntlmssp_state->neg_flags;
 221
 222         /* get the right name to fill in as 'target' */
 223         target_name = ntlmssp_target_name(gensec_ntlmssp_state,
 224                                           neg_flags, &chal_flags);
 225         if (target_name == NULL)
 226                 return NT_STATUS_INVALID_PARAMETER;
 227
 228         gensec_ntlmssp_state->chal = data_blob_talloc(gensec_ntlmssp_state, cryptkey, 8);
 229         gensec_ntlmssp_state->internal_chal = data_blob_talloc(gensec_ntlmssp_state, cryptkey, 8);
 230
 231         /* This should be a 'netbios domain -> DNS domain' mapping */
 232         dnsdomname[0] = '\0';
 233         get_mydomname(dnsdomname);
 234         strlower_m(dnsdomname);
 235
 236         dnsname[0] = '\0';
 237         get_myfullname(dnsname);
 238
 239         /* This creates the 'blob' of names that appears at the end of the packet */
 240         if (chal_flags & NTLMSSP_CHAL_TARGET_INFO)
 241         {
 242                 const char *target_name_dns = "";
 243                 if (chal_flags |= NTLMSSP_TARGET_TYPE_DOMAIN) {
 244                         target_name_dns = dnsdomname;
 245                 } else if (chal_flags |= NTLMSSP_TARGET_TYPE_SERVER) {
 246                         target_name_dns = dnsname;
 247                 }
 248
 249                 msrpc_gen(out_mem_ctx,
 250                           &struct_blob, "aaaaa",
 251                           NTLMSSP_NAME_TYPE_DOMAIN, target_name,
 252                           NTLMSSP_NAME_TYPE_SERVER, gensec_ntlmssp_state->server_name,
 253                           NTLMSSP_NAME_TYPE_DOMAIN_DNS, dnsdomname,
 254                           NTLMSSP_NAME_TYPE_SERVER_DNS, dnsname,
 255                           0, "");
 256         } else {
 257                 struct_blob = data_blob(NULL, 0);
 258         }
 259
 260         {
 261                 /* Marshel the packet in the right format, be it unicode or ASCII */
 262                 const char *gen_string;
 263                 if (gensec_ntlmssp_state->unicode) {
 264                         gen_string = "CdUdbddB";
 265                 } else {
 266                         gen_string = "CdAdbddB";
 267                 }
 268
 269                 msrpc_gen(out_mem_ctx,
 270                           out, gen_string,
 271                           "NTLMSSP",
 272                           NTLMSSP_CHALLENGE,
 273                           target_name,
 274                           chal_flags,
 275                           cryptkey, 8,
 276                           0, 0,
 277                           struct_blob.data, struct_blob.length);
 278         }
 279
 280         gensec_ntlmssp_state->expected_state = NTLMSSP_AUTH;
 281
 282         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 283 }
 284
 285 /**
 286  * Next state function for the Authenticate packet
 287  *
 288  * @param gensec_ntlmssp_state NTLMSSP State
 289  * @param request The request, as a DATA_BLOB
 290  * @return Errors or NT_STATUS_OK.
 291  */
 292
 293 static NTSTATUS ntlmssp_server_preauth(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
 294                                        const DATA_BLOB request)
 295 {
 296         uint32_t ntlmssp_command, auth_flags;
 297         NTSTATUS nt_status;
 298
 299         uint8_t session_nonce_hash[16];
 300
 301         const char *parse_string;
 302         char *domain = NULL;
 303         char *user = NULL;
 304         char *workstation = NULL;
 305
 306 #if 0
 307         file_save("ntlmssp_auth.dat", request.data, request.length);
 308 #endif
 309
 310         if (gensec_ntlmssp_state->unicode) {
 311                 parse_string = "CdBBUUUBd";
 312         } else {
 313                 parse_string = "CdBBAAABd";
 314         }
 315
 316         /* zero these out */
 317         data_blob_free(&gensec_ntlmssp_state->lm_resp);
 318         data_blob_free(&gensec_ntlmssp_state->nt_resp);
 319         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 320
 321         gensec_ntlmssp_state->user = NULL;
 322         gensec_ntlmssp_state->domain = NULL;
 323         gensec_ntlmssp_state->workstation = NULL;
 324
 325         /* now the NTLMSSP encoded auth hashes */
 326         if (!msrpc_parse(gensec_ntlmssp_state,
 327                          &request, parse_string,
 328                          "NTLMSSP",
 329                          &ntlmssp_command,
 330                          &gensec_ntlmssp_state->lm_resp,
 331                          &gensec_ntlmssp_state->nt_resp,
 332                          &domain,
 333                          &user,
 334                          &workstation,
 335                          &gensec_ntlmssp_state->encrypted_session_key,
 336                          &auth_flags)) {
 337                 DEBUG(10, ("ntlmssp_server_auth: failed to parse NTLMSSP (nonfatal):\n"));
 338                 dump_data(10, request.data, request.length);
 339
 340                 /* zero this out */
 341                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 342                 auth_flags = 0;
 343
 344                 /* Try again with a shorter string (Win9X truncates this packet) */
 345                 if (gensec_ntlmssp_state->unicode) {
 346                         parse_string = "CdBBUUU";
 347                 } else {
 348                         parse_string = "CdBBAAA";
 349                 }
 350
 351                 /* now the NTLMSSP encoded auth hashes */
 352                 if (!msrpc_parse(gensec_ntlmssp_state,
 353                                  &request, parse_string,
 354                                  "NTLMSSP",
 355                                  &ntlmssp_command,
 356                                  &gensec_ntlmssp_state->lm_resp,
 357                                  &gensec_ntlmssp_state->nt_resp,
 358                                  &domain,
 359                                  &user,
 360                                  &workstation)) {
 361                         DEBUG(1, ("ntlmssp_server_auth: failed to parse NTLMSSP:\n"));
 362                         dump_data(2, request.data, request.length);
 363
 364                         return NT_STATUS_INVALID_PARAMETER;
 365                 }
 366         }
 367
 368         if (auth_flags)
 369                 ntlmssp_handle_neg_flags(gensec_ntlmssp_state, auth_flags, gensec_ntlmssp_state->allow_lm_key);
 370
 371         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_domain(gensec_ntlmssp_state, domain))) {
 372                 /* zero this out */
 373                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 374                 return nt_status;
 375         }
 376
 377         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_username(gensec_ntlmssp_state, user))) {
 378                 /* zero this out */
 379                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 380                 return nt_status;
 381         }
 382
 383         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_workstation(gensec_ntlmssp_state, workstation))) {
 384                 /* zero this out */
 385                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 386                 return nt_status;
 387         }
 388
 389         DEBUG(3,("Got user=[%s] domain=[%s] workstation=[%s] len1=%lu len2=%lu\n",
 390                  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));
 391
 392 #if 0
 393         file_save("nthash1.dat",  &gensec_ntlmssp_state->nt_resp.data,  &gensec_ntlmssp_state->nt_resp.length);
 394         file_save("lmhash1.dat",  &gensec_ntlmssp_state->lm_resp.data,  &gensec_ntlmssp_state->lm_resp.length);
 395 #endif
 396
 397         /* NTLM2 uses a 'challenge' that is made of up both the server challenge, and a
 398            client challenge
 399
 400            However, the NTLM2 flag may still be set for the real NTLMv2 logins, be careful.
 401         */
 402         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 403                 if (gensec_ntlmssp_state->nt_resp.length == 24 && gensec_ntlmssp_state->lm_resp.length == 24) {
 404                         struct MD5Context md5_session_nonce_ctx;
 405                         SMB_ASSERT(gensec_ntlmssp_state->internal_chal.data
 406                                    && gensec_ntlmssp_state->internal_chal.length == 8);
 407
 408                         gensec_ntlmssp_state->doing_ntlm2 = True;
 409
 410                         memcpy(gensec_ntlmssp_state->crypt.ntlm2.session_nonce, gensec_ntlmssp_state->internal_chal.data, 8);
 411                         memcpy(&gensec_ntlmssp_state->crypt.ntlm2.session_nonce[8], gensec_ntlmssp_state->lm_resp.data, 8);
 412
 413                         MD5Init(&md5_session_nonce_ctx);
 414                         MD5Update(&md5_session_nonce_ctx, gensec_ntlmssp_state->crypt.ntlm2.session_nonce, 16);
 415                         MD5Final(session_nonce_hash, &md5_session_nonce_ctx);
 416
 417                         gensec_ntlmssp_state->chal = data_blob_talloc(gensec_ntlmssp_state,
 418                                                                session_nonce_hash, 8);
 419
 420                         /* LM response is no longer useful, zero it out */
 421                         data_blob_free(&gensec_ntlmssp_state->lm_resp);
 422
 423                         /* We changed the effective challenge - set it */
 424                         if (!NT_STATUS_IS_OK(nt_status =
 425                                              gensec_ntlmssp_state->set_challenge(gensec_ntlmssp_state,
 426                                                                                  &gensec_ntlmssp_state->chal))) {
 427                                 /* zero this out */
 428                                 data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 429                                 return nt_status;
 430                         }
 431
 432                         /* LM Key is incompatible... */
 433                         gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 434                 }
 435         }
 436         return NT_STATUS_OK;
 437 }
 438
 439 /**
 440  * Next state function for the Authenticate packet
 441  * (after authentication - figures out the session keys etc)
 442  *
 443  * @param gensec_ntlmssp_state NTLMSSP State
 444  * @return Errors or NT_STATUS_OK.
 445  */
 446
 447 static NTSTATUS ntlmssp_server_postauth(struct gensec_security *gensec_security,
 448                                         DATA_BLOB *user_session_key,
 449                                         DATA_BLOB *lm_session_key)
 450 {
 451         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 452         NTSTATUS nt_status;
 453         DATA_BLOB session_key = data_blob(NULL, 0);
 454
 455         if (user_session_key)
 456                 dump_data_pw("USER session key:\n", user_session_key->data, user_session_key->length);
 457
 458         if (lm_session_key)
 459                 dump_data_pw("LM first-8:\n", lm_session_key->data, lm_session_key->length);
 460
 461         /* Handle the different session key derivation for NTLM2 */
 462         if (gensec_ntlmssp_state->doing_ntlm2) {
 463                 if (user_session_key && user_session_key->data && user_session_key->length == 16) {
 464                         session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 465                         hmac_md5(user_session_key->data, gensec_ntlmssp_state->crypt.ntlm2.session_nonce,
 466                                  sizeof(gensec_ntlmssp_state->crypt.ntlm2.session_nonce), session_key.data);
 467                         DEBUG(10,("ntlmssp_server_auth: Created NTLM2 session key.\n"));
 468                         dump_data_pw("NTLM2 session key:\n", session_key.data, session_key.length);
 469
 470                 } else {
 471                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM2 session key.\n"));
 472                         session_key = data_blob(NULL, 0);
 473                 }
 474         } else if ((gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 475                 /* Ensure we can never get here on NTLMv2 */
 476                 && (gensec_ntlmssp_state->nt_resp.length == 0 || gensec_ntlmssp_state->nt_resp.length == 24)) {
 477
 478                 if (lm_session_key && lm_session_key->data && lm_session_key->length >= 8) {
 479                         if (gensec_ntlmssp_state->lm_resp.data && gensec_ntlmssp_state->lm_resp.length == 24) {
 480                                 session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 481                                 SMBsesskeygen_lm_sess_key(lm_session_key->data, gensec_ntlmssp_state->lm_resp.data,
 482                                                           session_key.data);
 483                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 484                                 dump_data_pw("LM session key:\n", session_key.data, session_key.length);
 485                         } else {
 486
 487                                 /* When there is no LM response, just use zeros */
 488                                 static const uint8_t zeros[24];
 489                                 session_key = data_blob_talloc(gensec_ntlmssp_state, NULL, 16);
 490                                 SMBsesskeygen_lm_sess_key(zeros, zeros,
 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                         }
 495                 } else {
 496                         /* LM Key not selected */
 497                         gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 498
 499                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM session key.\n"));
 500                         session_key = data_blob(NULL, 0);
 501                 }
 502
 503         } else if (user_session_key && user_session_key->data) {
 504                 session_key = *user_session_key;
 505                 DEBUG(10,("ntlmssp_server_auth: Using unmodified nt session key.\n"));
 506                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 507
 508                 /* LM Key not selected */
 509                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 510
 511         } else if (lm_session_key && lm_session_key->data) {
 512                 /* Very weird to have LM key, but no user session key, but anyway.. */
 513                 session_key = *lm_session_key;
 514                 DEBUG(10,("ntlmssp_server_auth: Using unmodified lm 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 {
 521                 DEBUG(10,("ntlmssp_server_auth: Failed to create unmodified session key.\n"));
 522                 session_key = data_blob(NULL, 0);
 523
 524                 /* LM Key not selected */
 525                 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 526         }
 527
 528         /* With KEY_EXCH, the client supplies the proposed session key,
 529            but encrypts it with the long-term key */
 530         if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 531                 if (!gensec_ntlmssp_state->encrypted_session_key.data
 532                     || gensec_ntlmssp_state->encrypted_session_key.length != 16) {
 533                         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 534                         DEBUG(1, ("Client-supplied KEY_EXCH session key was of invalid length (%u)!\n",
 535                                   (unsigned)gensec_ntlmssp_state->encrypted_session_key.length));
 536                         return NT_STATUS_INVALID_PARAMETER;
 537                 } else if (!session_key.data || session_key.length != 16) {
 538                         DEBUG(5, ("server session key is invalid (len == %u), cannot do KEY_EXCH!\n",
 539                                   (unsigned)session_key.length));
 540                         gensec_ntlmssp_state->session_key = session_key;
 541                 } else {
 542                         dump_data_pw("KEY_EXCH session key (enc):\n",
 543                                      gensec_ntlmssp_state->encrypted_session_key.data,
 544                                      gensec_ntlmssp_state->encrypted_session_key.length);
 545                         arcfour_crypt(gensec_ntlmssp_state->encrypted_session_key.data,
 546                                       session_key.data,
 547                                       gensec_ntlmssp_state->encrypted_session_key.length);
 548                         gensec_ntlmssp_state->session_key = data_blob_talloc(gensec_ntlmssp_state,
 549                                                                       gensec_ntlmssp_state->encrypted_session_key.data,
 550                                                                       gensec_ntlmssp_state->encrypted_session_key.length);
 551                         dump_data_pw("KEY_EXCH session key:\n", gensec_ntlmssp_state->encrypted_session_key.data,
 552                                      gensec_ntlmssp_state->encrypted_session_key.length);
 553                 }
 554         } else {
 555                 gensec_ntlmssp_state->session_key = session_key;
 556         }
 557
 558         /* keep the session key around on the new context */
 559         talloc_steal(gensec_ntlmssp_state, session_key.data);
 560
 561         if ((gensec_security->want_features & GENSEC_FEATURE_SIGN)
 562             || (gensec_security->want_features & GENSEC_FEATURE_SEAL)) {
 563                 nt_status = ntlmssp_sign_init(gensec_ntlmssp_state);
 564         } else {
 565                 nt_status = NT_STATUS_OK;
 566         }
 567
 568         data_blob_free(&gensec_ntlmssp_state->encrypted_session_key);
 569
 570         /* allow arbitarily many authentications, but watch that this will cause a
 571            memory leak, until the gensec_ntlmssp_state is shutdown
 572         */
 573
 574         if (gensec_ntlmssp_state->server_multiple_authentications) {
 575                 gensec_ntlmssp_state->expected_state = NTLMSSP_AUTH;
 576         } else {
 577                 gensec_ntlmssp_state->expected_state = NTLMSSP_DONE;
 578         }
 579
 580         return nt_status;
 581 }
 582
 583
 584 /**
 585  * Next state function for the Authenticate packet
 586  *
 587  * @param gensec_security GENSEC state
 588  * @param out_mem_ctx Memory context for *out
 589  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
 590  * @param out The reply, as an allocated DATA_BLOB, caller to free.
 591  * @return Errors or NT_STATUS_OK if authentication sucessful
 592  */
 593
 594 NTSTATUS ntlmssp_server_auth(struct gensec_security *gensec_security,
 595                              TALLOC_CTX *out_mem_ctx,
 596                              const DATA_BLOB in, DATA_BLOB *out)
 597 {
 598         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 599         DATA_BLOB user_session_key = data_blob(NULL, 0);
 600         DATA_BLOB lm_session_key = data_blob(NULL, 0);
 601         NTSTATUS nt_status;
 602
 603         TALLOC_CTX *mem_ctx = talloc_new(out_mem_ctx);
 604         if (!mem_ctx) {
 605                 return NT_STATUS_NO_MEMORY;
 606         }
 607
 608         /* zero the outbound NTLMSSP packet */
 609         *out = data_blob_talloc(out_mem_ctx, NULL, 0);
 610
 611         if (!NT_STATUS_IS_OK(nt_status = ntlmssp_server_preauth(gensec_ntlmssp_state, in))) {
 612                 talloc_free(mem_ctx);
 613                 return nt_status;
 614         }
 615
 616         /*
 617          * Note we don't check here for NTLMv2 auth settings. If NTLMv2 auth
 618          * is required (by "ntlm auth = no" and "lm auth = no" being set in the
 619          * smb.conf file) and no NTLMv2 response was sent then the password check
 620          * will fail here. JRA.
 621          */
 622
 623         /* Finally, actually ask if the password is OK */
 624
 625         if (!NT_STATUS_IS_OK(nt_status = gensec_ntlmssp_state->check_password(gensec_ntlmssp_state, mem_ctx,
 626                                                                               &user_session_key, &lm_session_key))) {
 627                 talloc_free(mem_ctx);
 628                 return nt_status;
 629         }
 630
 631         if (gensec_security->want_features
 632             & (GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL|GENSEC_FEATURE_SESSION_KEY)) {
 633                 nt_status = ntlmssp_server_postauth(gensec_security, &user_session_key, &lm_session_key);
 634                 talloc_free(mem_ctx);
 635                 return nt_status;
 636         } else {
 637                 gensec_ntlmssp_state->session_key = data_blob(NULL, 0);
 638                 talloc_free(mem_ctx);
 639                 return NT_STATUS_OK;
 640         }
 641 }
 642
 643 /**
 644  * Return the challenge as determined by the authentication subsystem
 645  * @return an 8 byte random challenge
 646  */
 647
 648 static const uint8_t *auth_ntlmssp_get_challenge(const struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 649 {
 650         NTSTATUS status;
 651         const uint8_t *chal;
 652
 653         status = auth_get_challenge(gensec_ntlmssp_state->auth_context, &chal);
 654         if (!NT_STATUS_IS_OK(status)) {
 655                 return NULL;
 656         }
 657
 658         return chal;
 659 }
 660
 661 /**
 662  * Some authentication methods 'fix' the challenge, so we may not be able to set it
 663  *
 664  * @return If the effective challenge used by the auth subsystem may be modified
 665  */
 666 static BOOL auth_ntlmssp_may_set_challenge(const struct gensec_ntlmssp_state *gensec_ntlmssp_state)
 667 {
 668         return auth_challenge_may_be_modified(gensec_ntlmssp_state->auth_context);
 669 }
 670
 671 /**
 672  * NTLM2 authentication modifies the effective challenge,
 673  * @param challenge The new challenge value
 674  */
 675 static NTSTATUS auth_ntlmssp_set_challenge(struct gensec_ntlmssp_state *gensec_ntlmssp_state, DATA_BLOB *challenge)
 676 {
 677         NTSTATUS nt_status;
 678         struct auth_context *auth_context = gensec_ntlmssp_state->auth_context;
 679         const uint8_t *chal;
 680
 681         if (challenge->length != 8) {
 682                 return NT_STATUS_INVALID_PARAMETER;
 683         }
 684
 685         chal = challenge->data;
 686
 687         nt_status = auth_context_set_challenge(auth_context, chal, "NTLMSSP callback (NTLM2)");
 688
 689         return nt_status;
 690 }
 691
 692 /**
 693  * Check the password on an NTLMSSP login.
 694  *
 695  * Return the session keys used on the connection.
 696  */
 697
 698 static NTSTATUS auth_ntlmssp_check_password(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
 699                                             TALLOC_CTX *mem_ctx,
 700                                             DATA_BLOB *user_session_key, DATA_BLOB *lm_session_key)
 701 {
 702         NTSTATUS nt_status;
 703         struct auth_usersupplied_info *user_info = talloc(mem_ctx, struct auth_usersupplied_info);
 704         if (!user_info) {
 705                 return NT_STATUS_NO_MEMORY;
 706         }
 707
 708         user_info->logon_parameters = MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT | MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT;
 709         user_info->flags = 0;
 710         user_info->mapped_state = False;
 711         user_info->client.account_name = gensec_ntlmssp_state->user;
 712         user_info->client.domain_name = gensec_ntlmssp_state->domain;
 713         user_info->workstation_name = gensec_ntlmssp_state->workstation;
 714         user_info->remote_host = gensec_get_peer_addr(gensec_ntlmssp_state->gensec_security);
 715
 716         user_info->password_state = AUTH_PASSWORD_RESPONSE;
 717         user_info->password.response.lanman = gensec_ntlmssp_state->lm_resp;
 718         user_info->password.response.lanman.data = talloc_steal(user_info, gensec_ntlmssp_state->lm_resp.data);
 719         user_info->password.response.nt = gensec_ntlmssp_state->nt_resp;
 720         user_info->password.response.nt.data = talloc_steal(user_info, gensec_ntlmssp_state->nt_resp.data);
 721
 722         nt_status = auth_check_password(gensec_ntlmssp_state->auth_context, mem_ctx,
 723                                         user_info, &gensec_ntlmssp_state->server_info);
 724         talloc_free(user_info);
 725         NT_STATUS_NOT_OK_RETURN(nt_status);
 726
 727         talloc_steal(gensec_ntlmssp_state, gensec_ntlmssp_state->server_info);
 728
 729         if (gensec_ntlmssp_state->server_info->user_session_key.length) {
 730                 DEBUG(10, ("Got NT session key of length %u\n",
 731                            (unsigned)gensec_ntlmssp_state->server_info->user_session_key.length));
 732                 if (!talloc_reference(mem_ctx, gensec_ntlmssp_state->server_info->user_session_key.data)) {
 733                         return NT_STATUS_NO_MEMORY;
 734                 }
 735
 736                 *user_session_key = gensec_ntlmssp_state->server_info->user_session_key;
 737         }
 738         if (gensec_ntlmssp_state->server_info->lm_session_key.length) {
 739                 DEBUG(10, ("Got LM session key of length %u\n",
 740                            (unsigned)gensec_ntlmssp_state->server_info->lm_session_key.length));
 741                 if (!talloc_reference(mem_ctx, gensec_ntlmssp_state->server_info->lm_session_key.data)) {
 742                         return NT_STATUS_NO_MEMORY;
 743                 }
 744
 745                 *lm_session_key = gensec_ntlmssp_state->server_info->lm_session_key;
 746         }
 747         return nt_status;
 748 }
 749
 750 /**
 751  * Return the credentials of a logged on user, including session keys
 752  * etc.
 753  *
 754  * Only valid after a successful authentication
 755  *
 756  * May only be called once per authentication.
 757  *
 758  */
 759
 760 NTSTATUS gensec_ntlmssp_session_info(struct gensec_security *gensec_security,
 761                                      struct auth_session_info **session_info)
 762 {
 763         NTSTATUS nt_status;
 764         struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
 765
 766         nt_status = auth_generate_session_info(gensec_ntlmssp_state, gensec_ntlmssp_state->server_info, session_info);
 767         NT_STATUS_NOT_OK_RETURN(nt_status);
 768
 769         (*session_info)->session_key = data_blob_talloc(*session_info,
 770                                                         gensec_ntlmssp_state->session_key.data,
 771                                                         gensec_ntlmssp_state->session_key.length);
 772
 773         return NT_STATUS_OK;
 774 }
 775
 776 /**
 777  * Start NTLMSSP on the server side
 778  *
 779  */
 780 NTSTATUS gensec_ntlmssp_server_start(struct gensec_security *gensec_security)
 781 {
 782         NTSTATUS nt_status;
 783         struct gensec_ntlmssp_state *gensec_ntlmssp_state;
 784
 785         nt_status = gensec_ntlmssp_start(gensec_security);
 786         NT_STATUS_NOT_OK_RETURN(nt_status);
 787
 788         gensec_ntlmssp_state = gensec_security->private_data;
 789
 790         gensec_ntlmssp_state->role = NTLMSSP_SERVER;
 791
 792         gensec_ntlmssp_state->workstation = NULL;
 793         gensec_ntlmssp_state->server_name = lp_netbios_name();
 794
 795         gensec_ntlmssp_state->get_domain = lp_workgroup;
 796
 797         gensec_ntlmssp_state->expected_state = NTLMSSP_NEGOTIATE;
 798
 799         gensec_ntlmssp_state->allow_lm_key = (lp_lanman_auth()
 800                                           && lp_parm_bool(-1, "ntlmssp_server", "allow_lm_key", False));
 801
 802         gensec_ntlmssp_state->server_multiple_authentications = False;
 803
 804         gensec_ntlmssp_state->neg_flags =
 805                 NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_UNKNOWN_02000000;
 806
 807         gensec_ntlmssp_state->lm_resp = data_blob(NULL, 0);
 808         gensec_ntlmssp_state->nt_resp = data_blob(NULL, 0);
 809         gensec_ntlmssp_state->encrypted_session_key = data_blob(NULL, 0);
 810
 811         if (lp_parm_bool(-1, "ntlmssp_server", "128bit", True)) {
 812                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_128;
 813         }
 814
 815         if (lp_parm_bool(-1, "ntlmssp_server", "56bit", True)) {
 816                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
 817         }
 818
 819         if (lp_parm_bool(-1, "ntlmssp_server", "keyexchange", True)) {
 820                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_KEY_EXCH;
 821         }
 822
 823         if (lp_parm_bool(-1, "ntlmssp_server", "alwayssign", True)) {
 824                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
 825         }
 826
 827         if (lp_parm_bool(-1, "ntlmssp_server", "ntlm2", True)) {
 828                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_NTLM2;
 829         }
 830
 831         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 832                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SIGN;
 833         }
 834         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 835                 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
 836         }
 837
 838         nt_status = auth_context_create(gensec_ntlmssp_state,
 839                                         gensec_security->event_ctx,
 840                                         gensec_security->msg_ctx,
 841                                         &gensec_ntlmssp_state->auth_context);
 842         NT_STATUS_NOT_OK_RETURN(nt_status);
 843
 844         gensec_ntlmssp_state->get_challenge = auth_ntlmssp_get_challenge;
 845         gensec_ntlmssp_state->may_set_challenge = auth_ntlmssp_may_set_challenge;
 846         gensec_ntlmssp_state->set_challenge = auth_ntlmssp_set_challenge;
 847         gensec_ntlmssp_state->check_password = auth_ntlmssp_check_password;
 848         gensec_ntlmssp_state->server_role = lp_server_role();
 849
 850         return NT_STATUS_OK;
 851 }
 852