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 #include "../librpc/gen_ndr/ndr_netlogon.h"
  24 #include "rpc_client/cli_netlogon.h"
  25
  26 #undef DBGC_CLASS
  27 #define DBGC_CLASS DBGC_AUTH
  28
  29 extern bool global_machine_password_needs_changing;
  30 static struct named_mutex *mutex;
  31
  32 /*
  33  * Change machine password (called from main loop
  34  * idle timeout. Must be done as root.
  35  */
  36
  37 void attempt_machine_password_change(void)
  38 {
  39         unsigned char trust_passwd_hash[16];
  40         time_t lct;
  41         void *lock;
  42
  43         if (!global_machine_password_needs_changing) {
  44                 return;
  45         }
  46
  47         if (lp_security() != SEC_DOMAIN) {
  48                 return;
  49         }
  50
  51         /*
  52          * We're in domain level security, and the code that
  53          * read the machine password flagged that the machine
  54          * password needs changing.
  55          */
  56
  57         /*
  58          * First, open the machine password file with an exclusive lock.
  59          */
  60
  61         lock = secrets_get_trust_account_lock(NULL, lp_workgroup());
  62
  63         if (lock == NULL) {
  64                 DEBUG(0,("attempt_machine_password_change: unable to lock "
  65                         "the machine account password for machine %s in "
  66                         "domain %s.\n",
  67                         global_myname(), lp_workgroup() ));
  68                 return;
  69         }
  70
  71         if(!secrets_fetch_trust_account_password(lp_workgroup(),
  72                         trust_passwd_hash, &lct, NULL)) {
  73                 DEBUG(0,("attempt_machine_password_change: unable to read the "
  74                         "machine account password for %s in domain %s.\n",
  75                         global_myname(), lp_workgroup()));
  76                 TALLOC_FREE(lock);
  77                 return;
  78         }
  79
  80         /*
  81          * Make sure someone else hasn't already done this.
  82          */
  83
  84         if(time(NULL) < lct + lp_machine_password_timeout()) {
  85                 global_machine_password_needs_changing = false;
  86                 TALLOC_FREE(lock);
  87                 return;
  88         }
  89
  90         /* always just contact the PDC here */
  91
  92         change_trust_account_password( lp_workgroup(), NULL);
  93         global_machine_password_needs_changing = false;
  94         TALLOC_FREE(lock);
  95 }
  96
  97 /**
  98  * Connect to a remote server for (inter)domain security authenticaion.
  99  *
 100  * @param cli the cli to return containing the active connection
 101  * @param server either a machine name or text IP address to
 102  *               connect to.
 103  * @param setup_creds_as domain account to setup credentials as
 104  * @param sec_chan a switch value to distinguish between domain
 105  *                 member and interdomain authentication
 106  * @param trust_passwd the trust password to establish the
 107  *                     credentials with.
 108  *
 109  **/
 110
 111 static NTSTATUS connect_to_domain_password_server(struct cli_state **cli,
 112                                                 const char *domain,
 113                                                 const char *dc_name,
 114                                                 struct sockaddr_storage *dc_ss,
 115                                                 struct rpc_pipe_client **pipe_ret,
 116                                                 bool *retry)
 117 {
 118         NTSTATUS result;
 119         struct rpc_pipe_client *netlogon_pipe = NULL;
 120
 121         *cli = NULL;
 122
 123         *pipe_ret = NULL;
 124
 125         /* TODO: Send a SAMLOGON request to determine whether this is a valid
 126            logonserver.  We can avoid a 30-second timeout if the DC is down
 127            if the SAMLOGON request fails as it is only over UDP. */
 128
 129         /* we use a mutex to prevent two connections at once - when a
 130            Win2k PDC get two connections where one hasn't completed a
 131            session setup yet it will send a TCP reset to the first
 132            connection (tridge) */
 133
 134         /*
 135          * With NT4.x DC's *all* authentication must be serialized to avoid
 136          * ACCESS_DENIED errors if 2 auths are done from the same machine. JRA.
 137          */
 138
 139         mutex = grab_named_mutex(NULL, dc_name, 10);
 140         if (mutex == NULL) {
 141                 return NT_STATUS_NO_LOGON_SERVERS;
 142         }
 143
 144         /* Attempt connection */
 145         *retry = True;
 146         result = cli_full_connection(cli, global_myname(), dc_name, dc_ss, 0,
 147                 "IPC$", "IPC", "", "", "", 0, Undefined, retry);
 148
 149         if (!NT_STATUS_IS_OK(result)) {
 150                 /* map to something more useful */
 151                 if (NT_STATUS_EQUAL(result, NT_STATUS_UNSUCCESSFUL)) {
 152                         result = NT_STATUS_NO_LOGON_SERVERS;
 153                 }
 154
 155                 if (*cli) {
 156                         cli_shutdown(*cli);
 157                         *cli = NULL;
 158                 }
 159
 160                 TALLOC_FREE(mutex);
 161                 return result;
 162         }
 163
 164         /*
 165          * We now have an anonymous connection to IPC$ on the domain password server.
 166          */
 167
 168         /*
 169          * Even if the connect succeeds we need to setup the netlogon
 170          * pipe here. We do this as we may just have changed the domain
 171          * account password on the PDC and yet we may be talking to
 172          * a BDC that doesn't have this replicated yet. In this case
 173          * a successful connect to a DC needs to take the netlogon connect
 174          * into account also. This patch from "Bjart Kvarme" <bjart.kvarme@usit.uio.no>.
 175          */
 176
 177         /* open the netlogon pipe. */
 178         if (lp_client_schannel()) {
 179                 /* We also setup the creds chain in the open_schannel call. */
 180                 result = cli_rpc_pipe_open_schannel(
 181                         *cli, &ndr_table_netlogon.syntax_id, NCACN_NP,
 182                         DCERPC_AUTH_LEVEL_PRIVACY, domain, &netlogon_pipe);
 183         } else {
 184                 result = cli_rpc_pipe_open_noauth(
 185                         *cli, &ndr_table_netlogon.syntax_id, &netlogon_pipe);
 186         }
 187
 188         if (!NT_STATUS_IS_OK(result)) {
 189                 DEBUG(0,("connect_to_domain_password_server: unable to open the domain client session to \
 190 machine %s. Error was : %s.\n", dc_name, nt_errstr(result)));
 191                 cli_shutdown(*cli);
 192                 *cli = NULL;
 193                 TALLOC_FREE(mutex);
 194                 return result;
 195         }
 196
 197         if (!lp_client_schannel()) {
 198                 /* We need to set up a creds chain on an unauthenticated netlogon pipe. */
 199                 uint32_t neg_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
 200                 enum netr_SchannelType sec_chan_type = 0;
 201                 unsigned char machine_pwd[16];
 202                 const char *account_name;
 203
 204                 if (!get_trust_pw_hash(domain, machine_pwd, &account_name,
 205                                        &sec_chan_type))
 206                 {
 207                         DEBUG(0, ("connect_to_domain_password_server: could not fetch "
 208                         "trust account password for domain '%s'\n",
 209                                 domain));
 210                         cli_shutdown(*cli);
 211                         *cli = NULL;
 212                         TALLOC_FREE(mutex);
 213                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 214                 }
 215
 216                 result = rpccli_netlogon_setup_creds(netlogon_pipe,
 217                                         dc_name, /* server name */
 218                                         domain, /* domain */
 219                                         global_myname(), /* client name */
 220                                         account_name, /* machine account name */
 221                                         machine_pwd,
 222                                         sec_chan_type,
 223                                         &neg_flags);
 224
 225                 if (!NT_STATUS_IS_OK(result)) {
 226                         cli_shutdown(*cli);
 227                         *cli = NULL;
 228                         TALLOC_FREE(mutex);
 229                         return result;
 230                 }
 231         }
 232
 233         if(!netlogon_pipe) {
 234                 DEBUG(0,("connect_to_domain_password_server: unable to open the domain client session to \
 235 machine %s. Error was : %s.\n", dc_name, cli_errstr(*cli)));
 236                 cli_shutdown(*cli);
 237                 *cli = NULL;
 238                 TALLOC_FREE(mutex);
 239                 return NT_STATUS_NO_LOGON_SERVERS;
 240         }
 241
 242         /* We exit here with the mutex *locked*. JRA */
 243
 244         *pipe_ret = netlogon_pipe;
 245
 246         return NT_STATUS_OK;
 247 }
 248
 249 /***********************************************************************
 250  Do the same as security=server, but using NT Domain calls and a session
 251  key from the machine password.  If the server parameter is specified
 252  use it, otherwise figure out a server from the 'password server' param.
 253 ************************************************************************/
 254
 255 static NTSTATUS domain_client_validate(TALLOC_CTX *mem_ctx,
 256                                         const struct auth_usersupplied_info *user_info,
 257                                         const char *domain,
 258                                         uchar chal[8],
 259                                         struct auth_serversupplied_info **server_info,
 260                                         const char *dc_name,
 261                                         struct sockaddr_storage *dc_ss)
 262
 263 {
 264         struct netr_SamInfo3 *info3 = NULL;
 265         struct cli_state *cli = NULL;
 266         struct rpc_pipe_client *netlogon_pipe = NULL;
 267         NTSTATUS nt_status = NT_STATUS_NO_LOGON_SERVERS;
 268         int i;
 269         bool retry = True;
 270
 271         /*
 272          * At this point, smb_apasswd points to the lanman response to
 273          * the challenge in local_challenge, and smb_ntpasswd points to
 274          * the NT response to the challenge in local_challenge. Ship
 275          * these over the secure channel to a domain controller and
 276          * see if they were valid.
 277          */
 278
 279         /* rety loop for robustness */
 280
 281         for (i = 0; !NT_STATUS_IS_OK(nt_status) && retry && (i < 3); i++) {
 282                 nt_status = connect_to_domain_password_server(&cli,
 283                                                         domain,
 284                                                         dc_name,
 285                                                         dc_ss,
 286                                                         &netlogon_pipe,
 287                                                         &retry);
 288         }
 289
 290         if ( !NT_STATUS_IS_OK(nt_status) ) {
 291                 DEBUG(0,("domain_client_validate: Domain password server not available.\n"));
 292                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCESS_DENIED)) {
 293                         return NT_STATUS_TRUSTED_RELATIONSHIP_FAILURE;
 294                 }
 295                 return nt_status;
 296         }
 297
 298         /* store a successful connection */
 299
 300         saf_store( domain, cli->desthost );
 301
 302         /*
 303          * If this call succeeds, we now have lots of info about the user
 304          * in the info3 structure.
 305          */
 306
 307         nt_status = rpccli_netlogon_sam_network_logon(netlogon_pipe,
 308                                                       mem_ctx,
 309                                                       user_info->logon_parameters,/* flags such as 'allow workstation logon' */
 310                                                       dc_name,                    /* server name */
 311                                                       user_info->smb_name,        /* user name logging on. */
 312                                                       user_info->client_domain,   /* domain name */
 313                                                       user_info->workstation_name,/* workstation name */
 314                                                       chal,                       /* 8 byte challenge. */
 315                                                       user_info->lm_resp,         /* lanman 24 byte response */
 316                                                       user_info->nt_resp,         /* nt 24 byte response */
 317                                                       &info3);                    /* info3 out */
 318
 319         /* Let go as soon as possible so we avoid any potential deadlocks
 320            with winbind lookup up users or groups. */
 321
 322         TALLOC_FREE(mutex);
 323
 324         if (!NT_STATUS_IS_OK(nt_status)) {
 325                 DEBUG(0,("domain_client_validate: unable to validate password "
 326                          "for user %s in domain %s to Domain controller %s. "
 327                          "Error was %s.\n", user_info->smb_name,
 328                          user_info->client_domain, dc_name,
 329                          nt_errstr(nt_status)));
 330
 331                 /* map to something more useful */
 332                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_UNSUCCESSFUL)) {
 333                         nt_status = NT_STATUS_NO_LOGON_SERVERS;
 334                 }
 335         } else {
 336                 nt_status = make_server_info_info3(mem_ctx,
 337                                                 user_info->smb_name,
 338                                                 domain,
 339                                                 server_info,
 340                                                 info3);
 341
 342                 if (NT_STATUS_IS_OK(nt_status)) {
 343                         (*server_info)->nss_token |= user_info->was_mapped;
 344
 345                         if ( ! (*server_info)->guest) {
 346                                 /* if a real user check pam account restrictions */
 347                                 /* only really perfomed if "obey pam restriction" is true */
 348                                 nt_status = smb_pam_accountcheck((*server_info)->unix_name);
 349                                 if (  !NT_STATUS_IS_OK(nt_status)) {
 350                                         DEBUG(1, ("PAM account restriction prevents user login\n"));
 351                                         cli_shutdown(cli);
 352                                         TALLOC_FREE(info3);
 353                                         return nt_status;
 354                                 }
 355                         }
 356                 }
 357
 358                 netsamlogon_cache_store(user_info->smb_name, info3);
 359                 TALLOC_FREE(info3);
 360         }
 361
 362         /* Note - once the cli stream is shutdown the mem_ctx used
 363            to allocate the other_sids and gids structures has been deleted - so
 364            these pointers are no longer valid..... */
 365
 366         cli_shutdown(cli);
 367         return nt_status;
 368 }
 369
 370 /****************************************************************************
 371  Check for a valid username and password in security=domain mode.
 372 ****************************************************************************/
 373
 374 static NTSTATUS check_ntdomain_security(const struct auth_context *auth_context,
 375                                         void *my_private_data,
 376                                         TALLOC_CTX *mem_ctx,
 377                                         const struct auth_usersupplied_info *user_info,
 378                                         struct auth_serversupplied_info **server_info)
 379 {
 380         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 381         const char *domain = lp_workgroup();
 382         fstring dc_name;
 383         struct sockaddr_storage dc_ss;
 384
 385         if ( lp_server_role() != ROLE_DOMAIN_MEMBER ) {
 386                 DEBUG(0,("check_ntdomain_security: Configuration error!  Cannot use "
 387                         "ntdomain auth method when not a member of a domain.\n"));
 388                 return NT_STATUS_NOT_IMPLEMENTED;
 389         }
 390
 391         if (!user_info || !server_info || !auth_context) {
 392                 DEBUG(1,("check_ntdomain_security: Critical variables not present.  Failing.\n"));
 393                 return NT_STATUS_INVALID_PARAMETER;
 394         }
 395
 396         DEBUG(10, ("Check auth for: [%s]\n", user_info->internal_username));
 397
 398         /*
 399          * Check that the requested domain is not our own machine name.
 400          * If it is, we should never check the PDC here, we use our own local
 401          * password file.
 402          */
 403
 404         if(strequal(get_global_sam_name(), user_info->domain)) {
 405                 DEBUG(3,("check_ntdomain_security: Requested domain was for this machine.\n"));
 406                 return NT_STATUS_NOT_IMPLEMENTED;
 407         }
 408
 409         /* we need our DC to send the net_sam_logon() request to */
 410
 411         if ( !get_dc_name(domain, NULL, dc_name, &dc_ss) ) {
 412                 DEBUG(5,("check_ntdomain_security: unable to locate a DC for domain %s\n",
 413                         user_info->domain));
 414                 return NT_STATUS_NO_LOGON_SERVERS;
 415         }
 416
 417         nt_status = domain_client_validate(mem_ctx,
 418                                         user_info,
 419                                         domain,
 420                                         (uchar *)auth_context->challenge.data,
 421                                         server_info,
 422                                         dc_name,
 423                                         &dc_ss);
 424
 425         return nt_status;
 426 }
 427
 428 /* module initialisation */
 429 static NTSTATUS auth_init_ntdomain(struct auth_context *auth_context, const char* param, auth_methods **auth_method)
 430 {
 431         struct auth_methods *result;
 432
 433         result = TALLOC_ZERO_P(auth_context, struct auth_methods);
 434         if (result == NULL) {
 435                 return NT_STATUS_NO_MEMORY;
 436         }
 437         result->name = "ntdomain";
 438         result->auth = check_ntdomain_security;
 439
 440         *auth_method = result;
 441         return NT_STATUS_OK;
 442 }
 443
 444
 445 /****************************************************************************
 446  Check for a valid username and password in a trusted domain
 447 ****************************************************************************/
 448
 449 static NTSTATUS check_trustdomain_security(const struct auth_context *auth_context,
 450                                            void *my_private_data,
 451                                            TALLOC_CTX *mem_ctx,
 452                                            const struct auth_usersupplied_info *user_info,
 453                                            struct auth_serversupplied_info **server_info)
 454 {
 455         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 456         unsigned char trust_md4_password[16];
 457         char *trust_password;
 458         fstring dc_name;
 459         struct sockaddr_storage dc_ss;
 460
 461         if (!user_info || !server_info || !auth_context) {
 462                 DEBUG(1,("check_trustdomain_security: Critical variables not present.  Failing.\n"));
 463                 return NT_STATUS_INVALID_PARAMETER;
 464         }
 465
 466         DEBUG(10, ("Check auth for: [%s]\n", user_info->internal_username));
 467
 468         /*
 469          * Check that the requested domain is not our own machine name or domain name.
 470          */
 471
 472         if( strequal(get_global_sam_name(), user_info->domain)) {
 473                 DEBUG(3,("check_trustdomain_security: Requested domain [%s] was for this machine.\n",
 474                         user_info->domain));
 475                 return NT_STATUS_NOT_IMPLEMENTED;
 476         }
 477
 478         /* No point is bothering if this is not a trusted domain.
 479            This return makes "map to guest = bad user" work again.
 480            The logic is that if we know nothing about the domain, that
 481            user is not known to us and does not exist */
 482
 483         if ( !is_trusted_domain( user_info->domain ) )
 484                 return NT_STATUS_NOT_IMPLEMENTED;
 485
 486         /*
 487          * Get the trusted account password for the trusted domain
 488          * No need to become_root() as secrets_init() is done at startup.
 489          */
 490
 491         if (!pdb_get_trusteddom_pw(user_info->domain, &trust_password,
 492                                    NULL, NULL)) {
 493                 DEBUG(0, ("check_trustdomain_security: could not fetch trust "
 494                           "account password for domain %s\n",
 495                           user_info->domain));
 496                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 497         }
 498
 499 #ifdef DEBUG_PASSWORD
 500         DEBUG(100, ("Trust password for domain %s is %s\n", user_info->domain,
 501                     trust_password));
 502 #endif
 503         E_md4hash(trust_password, trust_md4_password);
 504         SAFE_FREE(trust_password);
 505
 506 #if 0
 507         /* Test if machine password is expired and need to be changed */
 508         if (time(NULL) > last_change_time + (time_t)lp_machine_password_timeout())
 509         {
 510                 global_machine_password_needs_changing = True;
 511         }
 512 #endif
 513
 514         /* use get_dc_name() for consistency even through we know that it will be
 515            a netbios name */
 516
 517         if ( !get_dc_name(user_info->domain, NULL, dc_name, &dc_ss) ) {
 518                 DEBUG(5,("check_trustdomain_security: unable to locate a DC for domain %s\n",
 519                         user_info->domain));
 520                 return NT_STATUS_NO_LOGON_SERVERS;
 521         }
 522
 523         nt_status = domain_client_validate(mem_ctx,
 524                                         user_info,
 525                                         user_info->domain,
 526                                         (uchar *)auth_context->challenge.data,
 527                                         server_info,
 528                                         dc_name,
 529                                         &dc_ss);
 530
 531         return nt_status;
 532 }
 533
 534 /* module initialisation */
 535 static NTSTATUS auth_init_trustdomain(struct auth_context *auth_context, const char* param, auth_methods **auth_method)
 536 {
 537         struct auth_methods *result;
 538
 539         result = TALLOC_ZERO_P(auth_context, struct auth_methods);
 540         if (result == NULL) {
 541                 return NT_STATUS_NO_MEMORY;
 542         }
 543         result->name = "trustdomain";
 544         result->auth = check_trustdomain_security;
 545
 546         *auth_method = result;
 547         return NT_STATUS_OK;
 548 }
 549
 550 NTSTATUS auth_domain_init(void)
 551 {
 552         smb_register_auth(AUTH_INTERFACE_VERSION, "trustdomain", auth_init_trustdomain);
 553         smb_register_auth(AUTH_INTERFACE_VERSION, "ntdomain", auth_init_ntdomain);
 554         return NT_STATUS_OK;
 555 }