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