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 #include "secrets.h"
  26
  27 #undef DBGC_CLASS
  28 #define DBGC_CLASS DBGC_AUTH
  29
  30 extern bool global_machine_password_needs_changing;
  31 static struct named_mutex *mutex;
  32
  33 /*
  34  * Change machine password (called from main loop
  35  * idle timeout. Must be done as root.
  36  */
  37
  38 void attempt_machine_password_change(void)
  39 {
  40         unsigned char trust_passwd_hash[16];
  41         time_t lct;
  42         void *lock;
  43
  44         if (!global_machine_password_needs_changing) {
  45                 return;
  46         }
  47
  48         if (lp_security() != SEC_DOMAIN) {
  49                 return;
  50         }
  51
  52         /*
  53          * We're in domain level security, and the code that
  54          * read the machine password flagged that the machine
  55          * password needs changing.
  56          */
  57
  58         /*
  59          * First, open the machine password file with an exclusive lock.
  60          */
  61
  62         lock = secrets_get_trust_account_lock(NULL, lp_workgroup());
  63
  64         if (lock == NULL) {
  65                 DEBUG(0,("attempt_machine_password_change: unable to lock "
  66                         "the machine account password for machine %s in "
  67                         "domain %s.\n",
  68                         global_myname(), lp_workgroup() ));
  69                 return;
  70         }
  71
  72         if(!secrets_fetch_trust_account_password(lp_workgroup(),
  73                         trust_passwd_hash, &lct, NULL)) {
  74                 DEBUG(0,("attempt_machine_password_change: unable to read the "
  75                         "machine account password for %s in domain %s.\n",
  76                         global_myname(), lp_workgroup()));
  77                 TALLOC_FREE(lock);
  78                 return;
  79         }
  80
  81         /*
  82          * Make sure someone else hasn't already done this.
  83          */
  84
  85         if(time(NULL) < lct + lp_machine_password_timeout()) {
  86                 global_machine_password_needs_changing = false;
  87                 TALLOC_FREE(lock);
  88                 return;
  89         }
  90
  91         /* always just contact the PDC here */
  92
  93         change_trust_account_password( lp_workgroup(), NULL);
  94         global_machine_password_needs_changing = false;
  95         TALLOC_FREE(lock);
  96 }
  97
  98 /**
  99  * Connect to a remote server for (inter)domain security authenticaion.
 100  *
 101  * @param cli the cli to return containing the active connection
 102  * @param server either a machine name or text IP address to
 103  *               connect to.
 104  * @param setup_creds_as domain account to setup credentials as
 105  * @param sec_chan a switch value to distinguish between domain
 106  *                 member and interdomain authentication
 107  * @param trust_passwd the trust password to establish the
 108  *                     credentials with.
 109  *
 110  **/
 111
 112 static NTSTATUS connect_to_domain_password_server(struct cli_state **cli,
 113                                                 const char *domain,
 114                                                 const char *dc_name,
 115                                                 struct sockaddr_storage *dc_ss,
 116                                                 struct rpc_pipe_client **pipe_ret,
 117                                                 bool *retry)
 118 {
 119         NTSTATUS result;
 120         struct rpc_pipe_client *netlogon_pipe = NULL;
 121
 122         *cli = NULL;
 123
 124         *pipe_ret = NULL;
 125
 126         /* TODO: Send a SAMLOGON request to determine whether this is a valid
 127            logonserver.  We can avoid a 30-second timeout if the DC is down
 128            if the SAMLOGON request fails as it is only over UDP. */
 129
 130         /* we use a mutex to prevent two connections at once - when a
 131            Win2k PDC get two connections where one hasn't completed a
 132            session setup yet it will send a TCP reset to the first
 133            connection (tridge) */
 134
 135         /*
 136          * With NT4.x DC's *all* authentication must be serialized to avoid
 137          * ACCESS_DENIED errors if 2 auths are done from the same machine. JRA.
 138          */
 139
 140         mutex = grab_named_mutex(NULL, dc_name, 10);
 141         if (mutex == NULL) {
 142                 return NT_STATUS_NO_LOGON_SERVERS;
 143         }
 144
 145         /* Attempt connection */
 146         *retry = True;
 147         result = cli_full_connection(cli, global_myname(), dc_name, dc_ss, 0,
 148                 "IPC$", "IPC", "", "", "", 0, Undefined, retry);
 149
 150         if (!NT_STATUS_IS_OK(result)) {
 151                 /* map to something more useful */
 152                 if (NT_STATUS_EQUAL(result, NT_STATUS_UNSUCCESSFUL)) {
 153                         result = NT_STATUS_NO_LOGON_SERVERS;
 154                 }
 155
 156                 if (*cli) {
 157                         cli_shutdown(*cli);
 158                         *cli = NULL;
 159                 }
 160
 161                 TALLOC_FREE(mutex);
 162                 return result;
 163         }
 164
 165         /*
 166          * We now have an anonymous connection to IPC$ on the domain password server.
 167          */
 168
 169         /*
 170          * Even if the connect succeeds we need to setup the netlogon
 171          * pipe here. We do this as we may just have changed the domain
 172          * account password on the PDC and yet we may be talking to
 173          * a BDC that doesn't have this replicated yet. In this case
 174          * a successful connect to a DC needs to take the netlogon connect
 175          * into account also. This patch from "Bjart Kvarme" <bjart.kvarme@usit.uio.no>.
 176          */
 177
 178         /* open the netlogon pipe. */
 179         if (lp_client_schannel()) {
 180                 /* We also setup the creds chain in the open_schannel call. */
 181                 result = cli_rpc_pipe_open_schannel(
 182                         *cli, &ndr_table_netlogon.syntax_id, NCACN_NP,
 183                         DCERPC_AUTH_LEVEL_PRIVACY, domain, &netlogon_pipe);
 184         } else {
 185                 result = cli_rpc_pipe_open_noauth(
 186                         *cli, &ndr_table_netlogon.syntax_id, &netlogon_pipe);
 187         }
 188
 189         if (!NT_STATUS_IS_OK(result)) {
 190                 DEBUG(0,("connect_to_domain_password_server: unable to open the domain client session to \
 191 machine %s. Error was : %s.\n", dc_name, nt_errstr(result)));
 192                 cli_shutdown(*cli);
 193                 *cli = NULL;
 194                 TALLOC_FREE(mutex);
 195                 return result;
 196         }
 197
 198         if (!lp_client_schannel()) {
 199                 /* We need to set up a creds chain on an unauthenticated netlogon pipe. */
 200                 uint32_t neg_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
 201                 enum netr_SchannelType sec_chan_type = 0;
 202                 unsigned char machine_pwd[16];
 203                 const char *account_name;
 204
 205                 if (!get_trust_pw_hash(domain, machine_pwd, &account_name,
 206                                        &sec_chan_type))
 207                 {
 208                         DEBUG(0, ("connect_to_domain_password_server: could not fetch "
 209                         "trust account password for domain '%s'\n",
 210                                 domain));
 211                         cli_shutdown(*cli);
 212                         *cli = NULL;
 213                         TALLOC_FREE(mutex);
 214                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 215                 }
 216
 217                 result = rpccli_netlogon_setup_creds(netlogon_pipe,
 218                                         dc_name, /* server name */
 219                                         domain, /* domain */
 220                                         global_myname(), /* client name */
 221                                         account_name, /* machine account name */
 222                                         machine_pwd,
 223                                         sec_chan_type,
 224                                         &neg_flags);
 225
 226                 if (!NT_STATUS_IS_OK(result)) {
 227                         cli_shutdown(*cli);
 228                         *cli = NULL;
 229                         TALLOC_FREE(mutex);
 230                         return result;
 231                 }
 232         }
 233
 234         if(!netlogon_pipe) {
 235                 DEBUG(0,("connect_to_domain_password_server: unable to open the domain client session to \
 236 machine %s. Error was : %s.\n", dc_name, cli_errstr(*cli)));
 237                 cli_shutdown(*cli);
 238                 *cli = NULL;
 239                 TALLOC_FREE(mutex);
 240                 return NT_STATUS_NO_LOGON_SERVERS;
 241         }
 242
 243         /* We exit here with the mutex *locked*. JRA */
 244
 245         *pipe_ret = netlogon_pipe;
 246
 247         return NT_STATUS_OK;
 248 }
 249
 250 /***********************************************************************
 251  Do the same as security=server, but using NT Domain calls and a session
 252  key from the machine password.  If the server parameter is specified
 253  use it, otherwise figure out a server from the 'password server' param.
 254 ************************************************************************/
 255
 256 static NTSTATUS domain_client_validate(TALLOC_CTX *mem_ctx,
 257                                         const struct auth_usersupplied_info *user_info,
 258                                         const char *domain,
 259                                         uchar chal[8],
 260                                         struct auth_serversupplied_info **server_info,
 261                                         const char *dc_name,
 262                                         struct sockaddr_storage *dc_ss)
 263
 264 {
 265         struct netr_SamInfo3 *info3 = NULL;
 266         struct cli_state *cli = NULL;
 267         struct rpc_pipe_client *netlogon_pipe = NULL;
 268         NTSTATUS nt_status = NT_STATUS_NO_LOGON_SERVERS;
 269         int i;
 270         bool retry = True;
 271
 272         /*
 273          * At this point, smb_apasswd points to the lanman response to
 274          * the challenge in local_challenge, and smb_ntpasswd points to
 275          * the NT response to the challenge in local_challenge. Ship
 276          * these over the secure channel to a domain controller and
 277          * see if they were valid.
 278          */
 279
 280         /* rety loop for robustness */
 281
 282         for (i = 0; !NT_STATUS_IS_OK(nt_status) && retry && (i < 3); i++) {
 283                 nt_status = connect_to_domain_password_server(&cli,
 284                                                         domain,
 285                                                         dc_name,
 286                                                         dc_ss,
 287                                                         &netlogon_pipe,
 288                                                         &retry);
 289         }
 290
 291         if ( !NT_STATUS_IS_OK(nt_status) ) {
 292                 DEBUG(0,("domain_client_validate: Domain password server not available.\n"));
 293                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCESS_DENIED)) {
 294                         return NT_STATUS_TRUSTED_RELATIONSHIP_FAILURE;
 295                 }
 296                 return nt_status;
 297         }
 298
 299         /* store a successful connection */
 300
 301         saf_store( domain, cli->desthost );
 302
 303         /*
 304          * If this call succeeds, we now have lots of info about the user
 305          * in the info3 structure.
 306          */
 307
 308         nt_status = rpccli_netlogon_sam_network_logon(netlogon_pipe,
 309                                                       mem_ctx,
 310                                                       user_info->logon_parameters,/* flags such as 'allow workstation logon' */
 311                                                       dc_name,                    /* server name */
 312                                                       user_info->client.account_name,        /* user name logging on. */
 313                                                       user_info->client.domain_name,   /* domain name */
 314                                                       user_info->workstation_name,/* workstation name */
 315                                                       chal,                       /* 8 byte challenge. */
 316                                                       user_info->password.response.lanman, /* lanman 24 byte response */
 317                                                       user_info->password.response.nt,     /* nt 24 byte response */
 318                                                       &info3);                    /* info3 out */
 319
 320         /* Let go as soon as possible so we avoid any potential deadlocks
 321            with winbind lookup up users or groups. */
 322
 323         TALLOC_FREE(mutex);
 324
 325         if (!NT_STATUS_IS_OK(nt_status)) {
 326                 DEBUG(0,("domain_client_validate: unable to validate password "
 327                          "for user %s in domain %s to Domain controller %s. "
 328                          "Error was %s.\n", user_info->client.account_name,
 329                          user_info->client.domain_name, dc_name,
 330                          nt_errstr(nt_status)));
 331
 332                 /* map to something more useful */
 333                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_UNSUCCESSFUL)) {
 334                         nt_status = NT_STATUS_NO_LOGON_SERVERS;
 335                 }
 336         } else {
 337                 nt_status = make_server_info_info3(mem_ctx,
 338                                                 user_info->client.account_name,
 339                                                 domain,
 340                                                 server_info,
 341                                                 info3);
 342
 343                 if (NT_STATUS_IS_OK(nt_status)) {
 344                         (*server_info)->nss_token |= user_info->was_mapped;
 345
 346                         if ( ! (*server_info)->guest) {
 347                                 /* if a real user check pam account restrictions */
 348                                 /* only really perfomed if "obey pam restriction" is true */
 349                                 nt_status = smb_pam_accountcheck((*server_info)->unix_name);
 350                                 if (  !NT_STATUS_IS_OK(nt_status)) {
 351                                         DEBUG(1, ("PAM account restriction prevents user login\n"));
 352                                         cli_shutdown(cli);
 353                                         TALLOC_FREE(info3);
 354                                         return nt_status;
 355                                 }
 356                         }
 357                 }
 358
 359                 netsamlogon_cache_store(user_info->client.account_name, info3);
 360                 TALLOC_FREE(info3);
 361         }
 362
 363         /* Note - once the cli stream is shutdown the mem_ctx used
 364            to allocate the other_sids and gids structures has been deleted - so
 365            these pointers are no longer valid..... */
 366
 367         cli_shutdown(cli);
 368         return nt_status;
 369 }
 370
 371 /****************************************************************************
 372  Check for a valid username and password in security=domain mode.
 373 ****************************************************************************/
 374
 375 static NTSTATUS check_ntdomain_security(const struct auth_context *auth_context,
 376                                         void *my_private_data,
 377                                         TALLOC_CTX *mem_ctx,
 378                                         const struct auth_usersupplied_info *user_info,
 379                                         struct auth_serversupplied_info **server_info)
 380 {
 381         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 382         const char *domain = lp_workgroup();
 383         fstring dc_name;
 384         struct sockaddr_storage dc_ss;
 385
 386         if ( lp_server_role() != ROLE_DOMAIN_MEMBER ) {
 387                 DEBUG(0,("check_ntdomain_security: Configuration error!  Cannot use "
 388                         "ntdomain auth method when not a member of a domain.\n"));
 389                 return NT_STATUS_NOT_IMPLEMENTED;
 390         }
 391
 392         if (!user_info || !server_info || !auth_context) {
 393                 DEBUG(1,("check_ntdomain_security: Critical variables not present.  Failing.\n"));
 394                 return NT_STATUS_INVALID_PARAMETER;
 395         }
 396
 397         DEBUG(10, ("Check auth for: [%s]\n", user_info->mapped.account_name));
 398
 399         /*
 400          * Check that the requested domain is not our own machine name.
 401          * If it is, we should never check the PDC here, we use our own local
 402          * password file.
 403          */
 404
 405         if(strequal(get_global_sam_name(), user_info->mapped.domain_name)) {
 406                 DEBUG(3,("check_ntdomain_security: Requested domain was for this machine.\n"));
 407                 return NT_STATUS_NOT_IMPLEMENTED;
 408         }
 409
 410         /* we need our DC to send the net_sam_logon() request to */
 411
 412         if ( !get_dc_name(domain, NULL, dc_name, &dc_ss) ) {
 413                 DEBUG(5,("check_ntdomain_security: unable to locate a DC for domain %s\n",
 414                         user_info->mapped.domain_name));
 415                 return NT_STATUS_NO_LOGON_SERVERS;
 416         }
 417
 418         nt_status = domain_client_validate(mem_ctx,
 419                                         user_info,
 420                                         domain,
 421                                         (uchar *)auth_context->challenge.data,
 422                                         server_info,
 423                                         dc_name,
 424                                         &dc_ss);
 425
 426         return nt_status;
 427 }
 428
 429 /* module initialisation */
 430 static NTSTATUS auth_init_ntdomain(struct auth_context *auth_context, const char* param, auth_methods **auth_method)
 431 {
 432         struct auth_methods *result;
 433
 434         result = TALLOC_ZERO_P(auth_context, struct auth_methods);
 435         if (result == NULL) {
 436                 return NT_STATUS_NO_MEMORY;
 437         }
 438         result->name = "ntdomain";
 439         result->auth = check_ntdomain_security;
 440
 441         *auth_method = result;
 442         return NT_STATUS_OK;
 443 }
 444
 445
 446 /****************************************************************************
 447  Check for a valid username and password in a trusted domain
 448 ****************************************************************************/
 449
 450 static NTSTATUS check_trustdomain_security(const struct auth_context *auth_context,
 451                                            void *my_private_data,
 452                                            TALLOC_CTX *mem_ctx,
 453                                            const struct auth_usersupplied_info *user_info,
 454                                            struct auth_serversupplied_info **server_info)
 455 {
 456         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 457         unsigned char trust_md4_password[16];
 458         char *trust_password;
 459         fstring dc_name;
 460         struct sockaddr_storage dc_ss;
 461
 462         if (!user_info || !server_info || !auth_context) {
 463                 DEBUG(1,("check_trustdomain_security: Critical variables not present.  Failing.\n"));
 464                 return NT_STATUS_INVALID_PARAMETER;
 465         }
 466
 467         DEBUG(10, ("Check auth for: [%s]\n", user_info->mapped.account_name));
 468
 469         /*
 470          * Check that the requested domain is not our own machine name or domain name.
 471          */
 472
 473         if( strequal(get_global_sam_name(), user_info->mapped.domain_name)) {
 474                 DEBUG(3,("check_trustdomain_security: Requested domain [%s] was for this machine.\n",
 475                         user_info->mapped.domain_name));
 476                 return NT_STATUS_NOT_IMPLEMENTED;
 477         }
 478
 479         /* No point is bothering if this is not a trusted domain.
 480            This return makes "map to guest = bad user" work again.
 481            The logic is that if we know nothing about the domain, that
 482            user is not known to us and does not exist */
 483
 484         if ( !is_trusted_domain( user_info->mapped.domain_name ) )
 485                 return NT_STATUS_NOT_IMPLEMENTED;
 486
 487         /*
 488          * Get the trusted account password for the trusted domain
 489          * No need to become_root() as secrets_init() is done at startup.
 490          */
 491
 492         if (!pdb_get_trusteddom_pw(user_info->mapped.domain_name, &trust_password,
 493                                    NULL, NULL)) {
 494                 DEBUG(0, ("check_trustdomain_security: could not fetch trust "
 495                           "account password for domain %s\n",
 496                           user_info->mapped.domain_name));
 497                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 498         }
 499
 500 #ifdef DEBUG_PASSWORD
 501         DEBUG(100, ("Trust password for domain %s is %s\n", user_info->mapped.domain_name,
 502                     trust_password));
 503 #endif
 504         E_md4hash(trust_password, trust_md4_password);
 505         SAFE_FREE(trust_password);
 506
 507 #if 0
 508         /* Test if machine password is expired and need to be changed */
 509         if (time(NULL) > last_change_time + (time_t)lp_machine_password_timeout())
 510         {
 511                 global_machine_password_needs_changing = True;
 512         }
 513 #endif
 514
 515         /* use get_dc_name() for consistency even through we know that it will be
 516            a netbios name */
 517
 518         if ( !get_dc_name(user_info->mapped.domain_name, NULL, dc_name, &dc_ss) ) {
 519                 DEBUG(5,("check_trustdomain_security: unable to locate a DC for domain %s\n",
 520                         user_info->mapped.domain_name));
 521                 return NT_STATUS_NO_LOGON_SERVERS;
 522         }
 523
 524         nt_status = domain_client_validate(mem_ctx,
 525                                         user_info,
 526                                         user_info->mapped.domain_name,
 527                                         (uchar *)auth_context->challenge.data,
 528                                         server_info,
 529                                         dc_name,
 530                                         &dc_ss);
 531
 532         return nt_status;
 533 }
 534
 535 /* module initialisation */
 536 static NTSTATUS auth_init_trustdomain(struct auth_context *auth_context, const char* param, auth_methods **auth_method)
 537 {
 538         struct auth_methods *result;
 539
 540         result = TALLOC_ZERO_P(auth_context, struct auth_methods);
 541         if (result == NULL) {
 542                 return NT_STATUS_NO_MEMORY;
 543         }
 544         result->name = "trustdomain";
 545         result->auth = check_trustdomain_security;
 546
 547         *auth_method = result;
 548         return NT_STATUS_OK;
 549 }
 550
 551 NTSTATUS auth_domain_init(void)
 552 {
 553         smb_register_auth(AUTH_INTERFACE_VERSION, "trustdomain", auth_init_trustdomain);
 554         smb_register_auth(AUTH_INTERFACE_VERSION, "ntdomain", auth_init_ntdomain);
 555         return NT_STATUS_OK;
 556 }