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