source3/auth/auth_domain.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Authenticate against a remote domain
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Andrew Bartlett 2001
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "../libcli/auth/libcli_auth.h"
  23
  24 #undef DBGC_CLASS
  25 #define DBGC_CLASS DBGC_AUTH
  26
  27 extern bool global_machine_password_needs_changing;
  28 static struct named_mutex *mutex;
  29
  30 /*
  31  * Change machine password (called from main loop
  32  * idle timeout. Must be done as root.
  33  */
  34
  35 void attempt_machine_password_change(void)
  36 {
  37         unsigned char trust_passwd_hash[16];
  38         time_t lct;
  39         void *lock;
  40
  41         if (!global_machine_password_needs_changing) {
  42                 return;
  43         }
  44
  45         if (lp_security() != SEC_DOMAIN) {
  46                 return;
  47         }
  48
  49         /*
  50          * We're in domain level security, and the code that
  51          * read the machine password flagged that the machine
  52          * password needs changing.
  53          */
  54
  55         /*
  56          * First, open the machine password file with an exclusive lock.
  57          */
  58
  59         lock = secrets_get_trust_account_lock(NULL, lp_workgroup());
  60
  61         if (lock == NULL) {
  62                 DEBUG(0,("attempt_machine_password_change: unable to lock "
  63                         "the machine account password for machine %s in "
  64                         "domain %s.\n",
  65                         global_myname(), lp_workgroup() ));
  66                 return;
  67         }
  68
  69         if(!secrets_fetch_trust_account_password(lp_workgroup(),
  70                         trust_passwd_hash, &lct, NULL)) {
  71                 DEBUG(0,("attempt_machine_password_change: unable to read the "
  72                         "machine account password for %s in domain %s.\n",
  73                         global_myname(), lp_workgroup()));
  74                 TALLOC_FREE(lock);
  75                 return;
  76         }
  77
  78         /*
  79          * Make sure someone else hasn't already done this.
  80          */
  81
  82         if(time(NULL) < lct + lp_machine_password_timeout()) {
  83                 global_machine_password_needs_changing = false;
  84                 TALLOC_FREE(lock);
  85                 return;
  86         }
  87
  88         /* always just contact the PDC here */
  89
  90         change_trust_account_password( lp_workgroup(), NULL);
  91         global_machine_password_needs_changing = false;
  92         TALLOC_FREE(lock);
  93 }
  94
  95 /**
  96  * Connect to a remote server for (inter)domain security authenticaion.
  97  *
  98  * @param cli the cli to return containing the active connection
  99  * @param server either a machine name or text IP address to
 100  *               connect to.
 101  * @param setup_creds_as domain account to setup credentials as
 102  * @param sec_chan a switch value to distinguish between domain
 103  *                 member and interdomain authentication
 104  * @param trust_passwd the trust password to establish the
 105  *                     credentials with.
 106  *
 107  **/
 108
 109 static NTSTATUS connect_to_domain_password_server(struct cli_state **cli,
 110                                                 const char *domain,
 111                                                 const char *dc_name,
 112                                                 struct sockaddr_storage *dc_ss,
 113                                                 struct rpc_pipe_client **pipe_ret,
 114                                                 bool *retry)
 115 {
 116         NTSTATUS result;
 117         struct rpc_pipe_client *netlogon_pipe = NULL;
 118
 119         *cli = NULL;
 120
 121         *pipe_ret = NULL;
 122
 123         /* TODO: Send a SAMLOGON request to determine whether this is a valid
 124            logonserver.  We can avoid a 30-second timeout if the DC is down
 125            if the SAMLOGON request fails as it is only over UDP. */
 126
 127         /* we use a mutex to prevent two connections at once - when a
 128            Win2k PDC get two connections where one hasn't completed a
 129            session setup yet it will send a TCP reset to the first
 130            connection (tridge) */
 131
 132         /*
 133          * With NT4.x DC's *all* authentication must be serialized to avoid
 134          * ACCESS_DENIED errors if 2 auths are done from the same machine. JRA.
 135          */
 136
 137         mutex = grab_named_mutex(NULL, dc_name, 10);
 138         if (mutex == NULL) {
 139                 return NT_STATUS_NO_LOGON_SERVERS;
 140         }
 141
 142         /* Attempt connection */
 143         *retry = True;
 144         result = cli_full_connection(cli, global_myname(), dc_name, dc_ss, 0,
 145                 "IPC$", "IPC", "", "", "", 0, Undefined, retry);
 146
 147         if (!NT_STATUS_IS_OK(result)) {
 148                 /* map to something more useful */
 149                 if (NT_STATUS_EQUAL(result, NT_STATUS_UNSUCCESSFUL)) {
 150                         result = NT_STATUS_NO_LOGON_SERVERS;
 151                 }
 152
 153                 if (*cli) {
 154                         cli_shutdown(*cli);
 155                         *cli = NULL;
 156                 }
 157
 158                 TALLOC_FREE(mutex);
 159                 return result;
 160         }
 161
 162         /*
 163          * We now have an anonymous connection to IPC$ on the domain password server.
 164          */
 165
 166         /*
 167          * Even if the connect succeeds we need to setup the netlogon
 168          * pipe here. We do this as we may just have changed the domain
 169          * account password on the PDC and yet we may be talking to
 170          * a BDC that doesn't have this replicated yet. In this case
 171          * a successful connect to a DC needs to take the netlogon connect
 172          * into account also. This patch from "Bjart Kvarme" <bjart.kvarme@usit.uio.no>.
 173          */
 174
 175         /* open the netlogon pipe. */
 176         if (lp_client_schannel()) {
 177                 /* We also setup the creds chain in the open_schannel call. */
 178                 result = cli_rpc_pipe_open_schannel(
 179                         *cli, &ndr_table_netlogon.syntax_id, NCACN_NP,
 180                         DCERPC_AUTH_LEVEL_PRIVACY, domain, &netlogon_pipe);
 181         } else {
 182                 result = cli_rpc_pipe_open_noauth(
 183                         *cli, &ndr_table_netlogon.syntax_id, &netlogon_pipe);
 184         }
 185
 186         if (!NT_STATUS_IS_OK(result)) {
 187                 DEBUG(0,("connect_to_domain_password_server: unable to open the domain client session to \
 188 machine %s. Error was : %s.\n", dc_name, nt_errstr(result)));
 189                 cli_shutdown(*cli);
 190                 *cli = NULL;
 191                 TALLOC_FREE(mutex);
 192                 return result;
 193         }
 194
 195         if (!lp_client_schannel()) {
 196                 /* We need to set up a creds chain on an unauthenticated netlogon pipe. */
 197                 uint32_t neg_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
 198                 enum netr_SchannelType sec_chan_type = 0;
 199                 unsigned char machine_pwd[16];
 200                 const char *account_name;
 201
 202                 if (!get_trust_pw_hash(domain, machine_pwd, &account_name,
 203                                        &sec_chan_type))
 204                 {
 205                         DEBUG(0, ("connect_to_domain_password_server: could not fetch "
 206                         "trust account password for domain '%s'\n",
 207                                 domain));
 208                         cli_shutdown(*cli);
 209                         *cli = NULL;
 210                         TALLOC_FREE(mutex);
 211                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 212                 }
 213
 214                 result = rpccli_netlogon_setup_creds(netlogon_pipe,
 215                                         dc_name, /* server name */
 216                                         domain, /* domain */
 217                                         global_myname(), /* client name */
 218                                         account_name, /* machine account name */
 219                                         machine_pwd,
 220                                         sec_chan_type,
 221                                         &neg_flags);
 222
 223                 if (!NT_STATUS_IS_OK(result)) {
 224                         cli_shutdown(*cli);
 225                         *cli = NULL;
 226                         TALLOC_FREE(mutex);
 227                         return result;
 228                 }
 229         }
 230
 231         if(!netlogon_pipe) {
 232                 DEBUG(0,("connect_to_domain_password_server: unable to open the domain client session to \
 233 machine %s. Error was : %s.\n", dc_name, cli_errstr(*cli)));
 234                 cli_shutdown(*cli);
 235                 *cli = NULL;
 236                 TALLOC_FREE(mutex);
 237                 return NT_STATUS_NO_LOGON_SERVERS;
 238         }
 239
 240         /* We exit here with the mutex *locked*. JRA */
 241
 242         *pipe_ret = netlogon_pipe;
 243
 244         return NT_STATUS_OK;
 245 }
 246
 247 /***********************************************************************
 248  Do the same as security=server, but using NT Domain calls and a session
 249  key from the machine password.  If the server parameter is specified
 250  use it, otherwise figure out a server from the 'password server' param.
 251 ************************************************************************/
 252
 253 static NTSTATUS domain_client_validate(TALLOC_CTX *mem_ctx,
 254                                         const auth_usersupplied_info *user_info,
 255                                         const char *domain,
 256                                         uchar chal[8],
 257                                         auth_serversupplied_info **server_info,
 258                                         const char *dc_name,
 259                                         struct sockaddr_storage *dc_ss)
 260
 261 {
 262         struct netr_SamInfo3 *info3 = NULL;
 263         struct cli_state *cli = NULL;
 264         struct rpc_pipe_client *netlogon_pipe = NULL;
 265         NTSTATUS nt_status = NT_STATUS_NO_LOGON_SERVERS;
 266         int i;
 267         bool retry = True;
 268
 269         /*
 270          * At this point, smb_apasswd points to the lanman response to
 271          * the challenge in local_challenge, and smb_ntpasswd points to
 272          * the NT response to the challenge in local_challenge. Ship
 273          * these over the secure channel to a domain controller and
 274          * see if they were valid.
 275          */
 276
 277         /* rety loop for robustness */
 278
 279         for (i = 0; !NT_STATUS_IS_OK(nt_status) && retry && (i < 3); i++) {
 280                 nt_status = connect_to_domain_password_server(&cli,
 281                                                         domain,
 282                                                         dc_name,
 283                                                         dc_ss,
 284                                                         &netlogon_pipe,
 285                                                         &retry);
 286         }
 287
 288         if ( !NT_STATUS_IS_OK(nt_status) ) {
 289                 DEBUG(0,("domain_client_validate: Domain password server not available.\n"));
 290                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCESS_DENIED)) {
 291                         return NT_STATUS_TRUSTED_RELATIONSHIP_FAILURE;
 292                 }
 293                 return nt_status;
 294         }
 295
 296         /* store a successful connection */
 297
 298         saf_store( domain, cli->desthost );
 299
 300         /*
 301          * If this call succeeds, we now have lots of info about the user
 302          * in the info3 structure.
 303          */
 304
 305         nt_status = rpccli_netlogon_sam_network_logon(netlogon_pipe,
 306                                                       mem_ctx,
 307                                                       user_info->logon_parameters,/* flags such as 'allow workstation logon' */
 308                                                       dc_name,                    /* server name */
 309                                                       user_info->smb_name,        /* user name logging on. */
 310                                                       user_info->client_domain,   /* domain name */
 311                                                       user_info->wksta_name,      /* workstation name */
 312                                                       chal,                       /* 8 byte challenge. */
 313                                                       user_info->lm_resp,         /* lanman 24 byte response */
 314                                                       user_info->nt_resp,         /* nt 24 byte response */
 315                                                       &info3);                    /* info3 out */
 316
 317         /* Let go as soon as possible so we avoid any potential deadlocks
 318            with winbind lookup up users or groups. */
 319
 320         TALLOC_FREE(mutex);
 321
 322         if (!NT_STATUS_IS_OK(nt_status)) {
 323                 DEBUG(0,("domain_client_validate: unable to validate password "
 324                          "for user %s in domain %s to Domain controller %s. "
 325                          "Error was %s.\n", user_info->smb_name,
 326                          user_info->client_domain, dc_name,
 327                          nt_errstr(nt_status)));
 328
 329                 /* map to something more useful */
 330                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_UNSUCCESSFUL)) {
 331                         nt_status = NT_STATUS_NO_LOGON_SERVERS;
 332                 }
 333         } else {
 334                 nt_status = make_server_info_info3(mem_ctx,
 335                                                 user_info->smb_name,
 336                                                 domain,
 337                                                 server_info,
 338                                                 info3);
 339
 340                 if (NT_STATUS_IS_OK(nt_status)) {
 341                         (*server_info)->nss_token |= user_info->was_mapped;
 342
 343                         if ( ! (*server_info)->guest) {
 344                                 /* if a real user check pam account restrictions */
 345                                 /* only really perfomed if "obey pam restriction" is true */
 346                                 nt_status = smb_pam_accountcheck((*server_info)->unix_name);
 347                                 if (  !NT_STATUS_IS_OK(nt_status)) {
 348                                         DEBUG(1, ("PAM account restriction prevents user login\n"));
 349                                         cli_shutdown(cli);
 350                                         TALLOC_FREE(info3);
 351                                         return nt_status;
 352                                 }
 353                         }
 354                 }
 355
 356                 netsamlogon_cache_store(user_info->smb_name, info3);
 357                 TALLOC_FREE(info3);
 358         }
 359
 360         /* Note - once the cli stream is shutdown the mem_ctx used
 361            to allocate the other_sids and gids structures has been deleted - so
 362            these pointers are no longer valid..... */
 363
 364         cli_shutdown(cli);
 365         return nt_status;
 366 }
 367
 368 /****************************************************************************
 369  Check for a valid username and password in security=domain mode.
 370 ****************************************************************************/
 371
 372 static NTSTATUS check_ntdomain_security(const struct auth_context *auth_context,
 373                                         void *my_private_data,
 374                                         TALLOC_CTX *mem_ctx,
 375                                         const auth_usersupplied_info *user_info,
 376                                         auth_serversupplied_info **server_info)
 377 {
 378         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 379         const char *domain = lp_workgroup();
 380         fstring dc_name;
 381         struct sockaddr_storage dc_ss;
 382
 383         if ( lp_server_role() != ROLE_DOMAIN_MEMBER ) {
 384                 DEBUG(0,("check_ntdomain_security: Configuration error!  Cannot use "
 385                         "ntdomain auth method when not a member of a domain.\n"));
 386                 return NT_STATUS_NOT_IMPLEMENTED;
 387         }
 388
 389         if (!user_info || !server_info || !auth_context) {
 390                 DEBUG(1,("check_ntdomain_security: Critical variables not present.  Failing.\n"));
 391                 return NT_STATUS_INVALID_PARAMETER;
 392         }
 393
 394         /*
 395          * Check that the requested domain is not our own machine name.
 396          * If it is, we should never check the PDC here, we use our own local
 397          * password file.
 398          */
 399
 400         if(strequal(get_global_sam_name(), user_info->domain)) {
 401                 DEBUG(3,("check_ntdomain_security: Requested domain was for this machine.\n"));
 402                 return NT_STATUS_NOT_IMPLEMENTED;
 403         }
 404
 405         /* we need our DC to send the net_sam_logon() request to */
 406
 407         if ( !get_dc_name(domain, NULL, dc_name, &dc_ss) ) {
 408                 DEBUG(5,("check_ntdomain_security: unable to locate a DC for domain %s\n",
 409                         user_info->domain));
 410                 return NT_STATUS_NO_LOGON_SERVERS;
 411         }
 412
 413         nt_status = domain_client_validate(mem_ctx,
 414                                         user_info,
 415                                         domain,
 416                                         (uchar *)auth_context->challenge.data,
 417                                         server_info,
 418                                         dc_name,
 419                                         &dc_ss);
 420
 421         return nt_status;
 422 }
 423
 424 /* module initialisation */
 425 static NTSTATUS auth_init_ntdomain(struct auth_context *auth_context, const char* param, auth_methods **auth_method)
 426 {
 427         if (!make_auth_methods(auth_context, auth_method)) {
 428                 return NT_STATUS_NO_MEMORY;
 429         }
 430
 431         (*auth_method)->name = "ntdomain";
 432         (*auth_method)->auth = check_ntdomain_security;
 433         return NT_STATUS_OK;
 434 }
 435
 436
 437 /****************************************************************************
 438  Check for a valid username and password in a trusted domain
 439 ****************************************************************************/
 440
 441 static NTSTATUS check_trustdomain_security(const struct auth_context *auth_context,
 442                                            void *my_private_data,
 443                                            TALLOC_CTX *mem_ctx,
 444                                            const auth_usersupplied_info *user_info,
 445                                            auth_serversupplied_info **server_info)
 446 {
 447         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 448         unsigned char trust_md4_password[16];
 449         char *trust_password;
 450         fstring dc_name;
 451         struct sockaddr_storage dc_ss;
 452
 453         if (!user_info || !server_info || !auth_context) {
 454                 DEBUG(1,("check_trustdomain_security: Critical variables not present.  Failing.\n"));
 455                 return NT_STATUS_INVALID_PARAMETER;
 456         }
 457
 458         /*
 459          * Check that the requested domain is not our own machine name or domain name.
 460          */
 461
 462         if( strequal(get_global_sam_name(), user_info->domain)) {
 463                 DEBUG(3,("check_trustdomain_security: Requested domain [%s] was for this machine.\n",
 464                         user_info->domain));
 465                 return NT_STATUS_NOT_IMPLEMENTED;
 466         }
 467
 468         /* No point is bothering if this is not a trusted domain.
 469            This return makes "map to guest = bad user" work again.
 470            The logic is that if we know nothing about the domain, that
 471            user is not known to us and does not exist */
 472
 473         if ( !is_trusted_domain( user_info->domain ) )
 474                 return NT_STATUS_NOT_IMPLEMENTED;
 475
 476         /*
 477          * Get the trusted account password for the trusted domain
 478          * No need to become_root() as secrets_init() is done at startup.
 479          */
 480
 481         if (!pdb_get_trusteddom_pw(user_info->domain, &trust_password,
 482                                    NULL, NULL)) {
 483                 DEBUG(0, ("check_trustdomain_security: could not fetch trust "
 484                           "account password for domain %s\n",
 485                           user_info->domain));
 486                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 487         }
 488
 489 #ifdef DEBUG_PASSWORD
 490         DEBUG(100, ("Trust password for domain %s is %s\n", user_info->domain,
 491                     trust_password));
 492 #endif
 493         E_md4hash(trust_password, trust_md4_password);
 494         SAFE_FREE(trust_password);
 495
 496 #if 0
 497         /* Test if machine password is expired and need to be changed */
 498         if (time(NULL) > last_change_time + (time_t)lp_machine_password_timeout())
 499         {
 500                 global_machine_password_needs_changing = True;
 501         }
 502 #endif
 503
 504         /* use get_dc_name() for consistency even through we know that it will be
 505            a netbios name */
 506
 507         if ( !get_dc_name(user_info->domain, NULL, dc_name, &dc_ss) ) {
 508                 DEBUG(5,("check_trustdomain_security: unable to locate a DC for domain %s\n",
 509                         user_info->domain));
 510                 return NT_STATUS_NO_LOGON_SERVERS;
 511         }
 512
 513         nt_status = domain_client_validate(mem_ctx,
 514                                         user_info,
 515                                         user_info->domain,
 516                                         (uchar *)auth_context->challenge.data,
 517                                         server_info,
 518                                         dc_name,
 519                                         &dc_ss);
 520
 521         return nt_status;
 522 }
 523
 524 /* module initialisation */
 525 static NTSTATUS auth_init_trustdomain(struct auth_context *auth_context, const char* param, auth_methods **auth_method)
 526 {
 527         if (!make_auth_methods(auth_context, auth_method)) {
 528                 return NT_STATUS_NO_MEMORY;
 529         }
 530
 531         (*auth_method)->name = "trustdomain";
 532         (*auth_method)->auth = check_trustdomain_security;
 533         return NT_STATUS_OK;
 534 }
 535
 536 NTSTATUS auth_domain_init(void)
 537 {
 538         smb_register_auth(AUTH_INTERFACE_VERSION, "trustdomain", auth_init_trustdomain);
 539         smb_register_auth(AUTH_INTERFACE_VERSION, "ntdomain", auth_init_ntdomain);
 540         return NT_STATUS_OK;
 541 }