source4/libnet/libnet_samsync.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Extract the user/system database from a remote SamSync server
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22
  23 #include "includes.h"
  24 #include "libnet/libnet.h"
  25 #include "libcli/auth/libcli_auth.h"
  26 #include "auth/gensec/gensec.h"
  27 #include "auth/credentials/credentials.h"
  28 #include "auth/gensec/schannel_proto.h"
  29 #include "librpc/gen_ndr/ndr_netlogon.h"
  30 #include "librpc/gen_ndr/ndr_netlogon_c.h"
  31 #include "param/param.h"
  32
  33
  34 /**
  35  * Decrypt and extract the user's passwords.
  36  *
  37  * The writes decrypted (no longer 'RID encrypted' or arcfour encrypted) passwords back into the structure
  38  */
  39 static NTSTATUS fix_user(TALLOC_CTX *mem_ctx,
  40                          struct creds_CredentialState *creds,
  41                          bool rid_crypt,
  42                          enum netr_SamDatabaseID database,
  43                          struct netr_DELTA_ENUM *delta,
  44                          char **error_string)
  45 {
  46
  47         uint32_t rid = delta->delta_id_union.rid;
  48         struct netr_DELTA_USER *user = delta->delta_union.user;
  49         struct samr_Password lm_hash;
  50         struct samr_Password nt_hash;
  51         const char *username = user->account_name.string;
  52
  53         if (rid_crypt) {
  54                 if (user->lm_password_present) {
  55                         sam_rid_crypt(rid, user->lmpassword.hash, lm_hash.hash, 0);
  56                         user->lmpassword = lm_hash;
  57                 }
  58
  59                 if (user->nt_password_present) {
  60                         sam_rid_crypt(rid, user->ntpassword.hash, nt_hash.hash, 0);
  61                         user->ntpassword = nt_hash;
  62                 }
  63         }
  64
  65         if (user->user_private_info.SensitiveData) {
  66                 DATA_BLOB data;
  67                 struct netr_USER_KEYS keys;
  68                 enum ndr_err_code ndr_err;
  69                 data.data = user->user_private_info.SensitiveData;
  70                 data.length = user->user_private_info.DataLength;
  71                 creds_arcfour_crypt(creds, data.data, data.length);
  72                 user->user_private_info.SensitiveData = data.data;
  73                 user->user_private_info.DataLength = data.length;
  74
  75                 ndr_err = ndr_pull_struct_blob(&data, mem_ctx, NULL, &keys, (ndr_pull_flags_fn_t)ndr_pull_netr_USER_KEYS);
  76                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  77                         *error_string = talloc_asprintf(mem_ctx, "Failed to parse Sensitive Data for %s:", username);
  78                         dump_data(10, data.data, data.length);
  79                         return ndr_map_error2ntstatus(ndr_err);
  80                 }
  81
  82                 if (keys.keys.keys2.lmpassword.length == 16) {
  83                         if (rid_crypt) {
  84                                 sam_rid_crypt(rid, keys.keys.keys2.lmpassword.pwd.hash, lm_hash.hash, 0);
  85                                 user->lmpassword = lm_hash;
  86                         } else {
  87                                 user->lmpassword = keys.keys.keys2.lmpassword.pwd;
  88                         }
  89                         user->lm_password_present = true;
  90                 }
  91                 if (keys.keys.keys2.ntpassword.length == 16) {
  92                         if (rid_crypt) {
  93                                 sam_rid_crypt(rid, keys.keys.keys2.ntpassword.pwd.hash, nt_hash.hash, 0);
  94                                 user->ntpassword = nt_hash;
  95                         } else {
  96                                 user->ntpassword = keys.keys.keys2.ntpassword.pwd;
  97                         }
  98                         user->nt_password_present = true;
  99                 }
 100                 /* TODO: rid decrypt history fields */
 101         }
 102         return NT_STATUS_OK;
 103 }
 104
 105 /**
 106  * Decrypt and extract the secrets
 107  *
 108  * The writes decrypted secrets back into the structure
 109  */
 110 static NTSTATUS fix_secret(TALLOC_CTX *mem_ctx,
 111                            struct creds_CredentialState *creds,
 112                            enum netr_SamDatabaseID database,
 113                            struct netr_DELTA_ENUM *delta,
 114                            char **error_string)
 115 {
 116         struct netr_DELTA_SECRET *secret = delta->delta_union.secret;
 117         creds_arcfour_crypt(creds, secret->current_cipher.cipher_data,
 118                             secret->current_cipher.maxlen);
 119
 120         creds_arcfour_crypt(creds, secret->old_cipher.cipher_data,
 121                             secret->old_cipher.maxlen);
 122
 123         return NT_STATUS_OK;
 124 }
 125
 126 /**
 127  * Fix up the delta, dealing with encryption issues so that the final
 128  * callback need only do the printing or application logic
 129  */
 130
 131 static NTSTATUS fix_delta(TALLOC_CTX *mem_ctx,
 132                           struct creds_CredentialState *creds,
 133                           bool rid_crypt,
 134                           enum netr_SamDatabaseID database,
 135                           struct netr_DELTA_ENUM *delta,
 136                           char **error_string)
 137 {
 138         NTSTATUS nt_status = NT_STATUS_OK;
 139         *error_string = NULL;
 140         switch (delta->delta_type) {
 141         case NETR_DELTA_USER:
 142         {
 143                 nt_status = fix_user(mem_ctx,
 144                                      creds,
 145                                      rid_crypt,
 146                                      database,
 147                                      delta,
 148                                      error_string);
 149                 break;
 150         }
 151         case NETR_DELTA_SECRET:
 152         {
 153                 nt_status = fix_secret(mem_ctx,
 154                                        creds,
 155                                        database,
 156                                        delta,
 157                                        error_string);
 158                 break;
 159         }
 160         default:
 161                 break;
 162         }
 163         return nt_status;
 164 }
 165
 166 NTSTATUS libnet_SamSync_netlogon(struct libnet_context *ctx, TALLOC_CTX *mem_ctx, struct libnet_SamSync *r)
 167 {
 168         NTSTATUS nt_status, dbsync_nt_status;
 169         TALLOC_CTX *samsync_ctx, *loop_ctx, *delta_ctx;
 170         struct creds_CredentialState *creds;
 171         struct netr_DatabaseSync dbsync;
 172         struct netr_Authenticator credential, return_authenticator;
 173         struct netr_DELTA_ENUM_ARRAY *delta_enum_array = NULL;
 174         struct cli_credentials *machine_account;
 175         struct dcerpc_pipe *p;
 176         struct libnet_context *machine_net_ctx;
 177         struct libnet_RpcConnect *c;
 178         struct libnet_SamSync_state *state;
 179         const enum netr_SamDatabaseID database_ids[] = {SAM_DATABASE_DOMAIN, SAM_DATABASE_BUILTIN, SAM_DATABASE_PRIVS};
 180         int i;
 181
 182         samsync_ctx = talloc_named(mem_ctx, 0, "SamSync top context");
 183
 184         if (!r->in.machine_account) {
 185                 machine_account = cli_credentials_init(samsync_ctx);
 186                 if (!machine_account) {
 187                         talloc_free(samsync_ctx);
 188                         return NT_STATUS_NO_MEMORY;
 189                 }
 190                 cli_credentials_set_conf(machine_account, ctx->lp_ctx);
 191                 nt_status = cli_credentials_set_machine_account(machine_account, ctx->lp_ctx);
 192                 if (!NT_STATUS_IS_OK(nt_status)) {
 193                         r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain machine account password - are we joined to the domain?");
 194                         talloc_free(samsync_ctx);
 195                         return nt_status;
 196                 }
 197         } else {
 198                 machine_account = r->in.machine_account;
 199         }
 200
 201         /* We cannot do this unless we are a BDC.  Check, before we get odd errors later */
 202         if (cli_credentials_get_secure_channel_type(machine_account) != SEC_CHAN_BDC) {
 203                 r->out.error_string
 204                         = talloc_asprintf(mem_ctx,
 205                                           "Our join to domain %s is not as a BDC (%d), please rejoin as a BDC",
 206                                           cli_credentials_get_domain(machine_account),
 207                                           cli_credentials_get_secure_channel_type(machine_account));
 208                 talloc_free(samsync_ctx);
 209                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 210         }
 211
 212         c = talloc(samsync_ctx, struct libnet_RpcConnect);
 213         if (!c) {
 214                 r->out.error_string = NULL;
 215                 talloc_free(samsync_ctx);
 216                 return NT_STATUS_NO_MEMORY;
 217         }
 218
 219         c->level              = LIBNET_RPC_CONNECT_DC_INFO;
 220         if (r->in.binding_string) {
 221                 c->in.binding = r->in.binding_string;
 222                 c->in.name    = NULL;
 223         } else {
 224                 c->in.binding = NULL;
 225                 c->in.name    = cli_credentials_get_domain(machine_account);
 226         }
 227
 228         /* prepare connect to the NETLOGON pipe of PDC */
 229         c->in.dcerpc_iface      = &ndr_table_netlogon;
 230
 231         /* We must do this as the machine, not as any command-line
 232          * user.  So we override the credentials in the
 233          * libnet_context */
 234         machine_net_ctx = talloc(samsync_ctx, struct libnet_context);
 235         if (!machine_net_ctx) {
 236                 r->out.error_string = NULL;
 237                 talloc_free(samsync_ctx);
 238                 return NT_STATUS_NO_MEMORY;
 239         }
 240         *machine_net_ctx = *ctx;
 241         machine_net_ctx->cred = machine_account;
 242
 243         /* connect to the NETLOGON pipe of the PDC */
 244         nt_status = libnet_RpcConnect(machine_net_ctx, samsync_ctx, c);
 245         if (!NT_STATUS_IS_OK(nt_status)) {
 246                 if (r->in.binding_string) {
 247                         r->out.error_string = talloc_asprintf(mem_ctx,
 248                                                               "Connection to NETLOGON pipe of DC %s failed: %s",
 249                                                               r->in.binding_string, c->out.error_string);
 250                 } else {
 251                         r->out.error_string = talloc_asprintf(mem_ctx,
 252                                                               "Connection to NETLOGON pipe of DC for %s failed: %s",
 253                                                               c->in.name, c->out.error_string);
 254                 }
 255                 talloc_free(samsync_ctx);
 256                 return nt_status;
 257         }
 258
 259         /* This makes a new pipe, on which we can do schannel.  We
 260          * should do this in the RpcConnect code, but the abstaction
 261          * layers do not suit yet */
 262
 263         nt_status = dcerpc_secondary_connection(c->out.dcerpc_pipe, &p,
 264                                                 c->out.dcerpc_pipe->binding);
 265
 266         if (!NT_STATUS_IS_OK(nt_status)) {
 267                 r->out.error_string = talloc_asprintf(mem_ctx,
 268                                                       "Secondary connection to NETLOGON pipe of DC %s failed: %s",
 269                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 270                 talloc_free(samsync_ctx);
 271                 return nt_status;
 272         }
 273
 274         nt_status = dcerpc_bind_auth_schannel(samsync_ctx, p, &ndr_table_netlogon,
 275                                               machine_account, ctx->lp_ctx, DCERPC_AUTH_LEVEL_PRIVACY);
 276
 277         if (!NT_STATUS_IS_OK(nt_status)) {
 278                 r->out.error_string = talloc_asprintf(mem_ctx,
 279                                                       "SCHANNEL authentication to NETLOGON pipe of DC %s failed: %s",
 280                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 281                 talloc_free(samsync_ctx);
 282                 return nt_status;
 283         }
 284
 285         state = talloc(samsync_ctx, struct libnet_SamSync_state);
 286         if (!state) {
 287                 r->out.error_string = NULL;
 288                 talloc_free(samsync_ctx);
 289                 return nt_status;
 290         }
 291
 292         state->domain_name     = c->out.domain_name;
 293         state->domain_sid      = c->out.domain_sid;
 294         state->realm           = c->out.realm;
 295         state->domain_guid     = c->out.guid;
 296         state->machine_net_ctx = machine_net_ctx;
 297         state->netlogon_pipe   = p;
 298
 299         /* initialise the callback layer.  It may wish to contact the
 300          * server with ldap, now we know the name */
 301
 302         if (r->in.init_fn) {
 303                 char *error_string;
 304                 nt_status = r->in.init_fn(samsync_ctx,
 305                                           r->in.fn_ctx,
 306                                           state,
 307                                           &error_string);
 308                 if (!NT_STATUS_IS_OK(nt_status)) {
 309                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 310                         talloc_free(samsync_ctx);
 311                         return nt_status;
 312                 }
 313         }
 314
 315         /* get NETLOGON credentials */
 316
 317         nt_status = dcerpc_schannel_creds(p->conn->security_state.generic_state, samsync_ctx, &creds);
 318         if (!NT_STATUS_IS_OK(nt_status)) {
 319                 r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain NETLOGON credentials from DCERPC/GENSEC layer");
 320                 talloc_free(samsync_ctx);
 321                 return nt_status;
 322         }
 323
 324         /* Setup details for the synchronisation */
 325
 326         ZERO_STRUCT(return_authenticator);
 327
 328         dbsync.in.logon_server = talloc_asprintf(samsync_ctx, "\\\\%s", dcerpc_server_name(p));
 329         dbsync.in.computername = cli_credentials_get_workstation(machine_account);
 330         dbsync.in.preferredmaximumlength = (uint32_t)-1;
 331         dbsync.in.return_authenticator = &return_authenticator;
 332         dbsync.out.return_authenticator = &return_authenticator;
 333         dbsync.out.delta_enum_array = &delta_enum_array;
 334
 335         for (i=0;i< ARRAY_SIZE(database_ids); i++) {
 336
 337                 uint32_t sync_context = 0;
 338
 339                 dbsync.in.database_id = database_ids[i];
 340                 dbsync.in.sync_context = &sync_context;
 341                 dbsync.out.sync_context = &sync_context;
 342
 343                 do {
 344                         int d;
 345                         loop_ctx = talloc_named(samsync_ctx, 0, "DatabaseSync loop context");
 346                         creds_client_authenticator(creds, &credential);
 347
 348                         dbsync.in.credential = &credential;
 349
 350                         dbsync_nt_status = dcerpc_netr_DatabaseSync(p, loop_ctx, &dbsync);
 351                         if (!NT_STATUS_IS_OK(dbsync_nt_status) &&
 352                             !NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES)) {
 353                                 r->out.error_string = talloc_asprintf(mem_ctx, "DatabaseSync failed - %s", nt_errstr(nt_status));
 354                                 talloc_free(samsync_ctx);
 355                                 return nt_status;
 356                         }
 357
 358                         if (!creds_client_check(creds, &dbsync.out.return_authenticator->cred)) {
 359                                 r->out.error_string = talloc_strdup(mem_ctx, "Credential chaining on incoming DatabaseSync failed");
 360                                 talloc_free(samsync_ctx);
 361                                 return NT_STATUS_ACCESS_DENIED;
 362                         }
 363
 364                         dbsync.in.sync_context = dbsync.out.sync_context;
 365
 366                         /* For every single remote 'delta' entry: */
 367                         for (d=0; d < delta_enum_array->num_deltas; d++) {
 368                                 char *error_string = NULL;
 369                                 delta_ctx = talloc_named(loop_ctx, 0, "DatabaseSync delta context");
 370                                 /* 'Fix' elements, by decrypting and
 371                                  * de-obfuscating the data */
 372                                 nt_status = fix_delta(delta_ctx,
 373                                                       creds,
 374                                                       r->in.rid_crypt,
 375                                                       dbsync.in.database_id,
 376                                                       &delta_enum_array->delta_enum[d],
 377                                                       &error_string);
 378                                 if (!NT_STATUS_IS_OK(nt_status)) {
 379                                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 380                                         talloc_free(samsync_ctx);
 381                                         return nt_status;
 382                                 }
 383
 384                                 /* Now call the callback.  This will
 385                                  * do something like print the data or
 386                                  * write to an ldb */
 387                                 nt_status = r->in.delta_fn(delta_ctx,
 388                                                            r->in.fn_ctx,
 389                                                            dbsync.in.database_id,
 390                                                            &delta_enum_array->delta_enum[d],
 391                                                            &error_string);
 392                                 if (!NT_STATUS_IS_OK(nt_status)) {
 393                                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 394                                         talloc_free(samsync_ctx);
 395                                         return nt_status;
 396                                 }
 397                                 talloc_free(delta_ctx);
 398                         }
 399                         talloc_free(loop_ctx);
 400                 } while (NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES));
 401
 402                 if (!NT_STATUS_IS_OK(dbsync_nt_status)) {
 403                         r->out.error_string = talloc_asprintf(mem_ctx, "libnet_SamSync_netlogon failed: unexpected inconsistancy. Should not get error %s here", nt_errstr(nt_status));
 404                         talloc_free(samsync_ctx);
 405                         return dbsync_nt_status;
 406                 }
 407                 nt_status = NT_STATUS_OK;
 408         }
 409         talloc_free(samsync_ctx);
 410         return nt_status;
 411 }
 412