source4/libnet/libnet_vampire.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 2 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, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23
  24 #include "includes.h"
  25 #include "libnet/libnet.h"
  26 #include "libcli/auth/libcli_auth.h"
  27 #include "auth/gensec/schannel_proto.h"
  28 #include "librpc/gen_ndr/ndr_netlogon_c.h"
  29
  30
  31 /**
  32  * Decrypt and extract the user's passwords.
  33  *
  34  * The writes decrypted (no longer 'RID encrypted' or arcfour encrypted) passwords back into the structure
  35  */
  36 static NTSTATUS fix_user(TALLOC_CTX *mem_ctx,
  37                          struct creds_CredentialState *creds,
  38                          enum netr_SamDatabaseID database,
  39                          struct netr_DELTA_ENUM *delta,
  40                          char **error_string)
  41 {
  42
  43         uint32_t rid = delta->delta_id_union.rid;
  44         struct netr_DELTA_USER *user = delta->delta_union.user;
  45         struct samr_Password lm_hash;
  46         struct samr_Password nt_hash;
  47         const char *username = user->account_name.string;
  48         NTSTATUS nt_status;
  49
  50         if (user->lm_password_present) {
  51                 sam_rid_crypt(rid, user->lmpassword.hash, lm_hash.hash, 0);
  52                 user->lmpassword = lm_hash;
  53         }
  54
  55         if (user->nt_password_present) {
  56                 sam_rid_crypt(rid, user->ntpassword.hash, nt_hash.hash, 0);
  57                 user->ntpassword = nt_hash;
  58         }
  59
  60         if (user->user_private_info.SensitiveData) {
  61                 DATA_BLOB data;
  62                 struct netr_USER_KEYS keys;
  63                 data.data = user->user_private_info.SensitiveData;
  64                 data.length = user->user_private_info.DataLength;
  65                 creds_arcfour_crypt(creds, data.data, data.length);
  66                 user->user_private_info.SensitiveData = data.data;
  67                 user->user_private_info.DataLength = data.length;
  68
  69                 nt_status = ndr_pull_struct_blob(&data, mem_ctx, &keys, (ndr_pull_flags_fn_t)ndr_pull_netr_USER_KEYS);
  70                 if (NT_STATUS_IS_OK(nt_status)) {
  71                         if (keys.keys.keys2.lmpassword.length == 16) {
  72                                 sam_rid_crypt(rid, keys.keys.keys2.lmpassword.pwd.hash, lm_hash.hash, 0);
  73                                 user->lmpassword = lm_hash;
  74                                 user->lm_password_present = True;
  75                         }
  76                         if (keys.keys.keys2.ntpassword.length == 16) {
  77                                 sam_rid_crypt(rid, keys.keys.keys2.ntpassword.pwd.hash, nt_hash.hash, 0);
  78                                 user->ntpassword = nt_hash;
  79                                 user->nt_password_present = True;
  80                         }
  81                 } else {
  82                         *error_string = talloc_asprintf(mem_ctx, "Failed to parse Sensitive Data for %s:\n", username);
  83                         dump_data(10, data.data, data.length);
  84                         return nt_status;
  85                 }
  86         }
  87         return NT_STATUS_OK;
  88 }
  89
  90 /**
  91  * Decrypt and extract the secrets
  92  *
  93  * The writes decrypted secrets back into the structure
  94  */
  95 static NTSTATUS fix_secret(TALLOC_CTX *mem_ctx,
  96                            struct creds_CredentialState *creds,
  97                            enum netr_SamDatabaseID database,
  98                            struct netr_DELTA_ENUM *delta,
  99                            char **error_string)
 100 {
 101         struct netr_DELTA_SECRET *secret = delta->delta_union.secret;
 102         creds_arcfour_crypt(creds, secret->current_cipher.cipher_data,
 103                             secret->current_cipher.maxlen);
 104
 105         creds_arcfour_crypt(creds, secret->old_cipher.cipher_data,
 106                             secret->old_cipher.maxlen);
 107
 108         return NT_STATUS_OK;
 109 }
 110
 111 /**
 112  * Fix up the delta, dealing with encryption issues so that the final
 113  * callback need only do the printing or application logic
 114  */
 115
 116 static NTSTATUS fix_delta(TALLOC_CTX *mem_ctx,
 117                           struct creds_CredentialState *creds,
 118                           enum netr_SamDatabaseID database,
 119                           struct netr_DELTA_ENUM *delta,
 120                           char **error_string)
 121 {
 122         NTSTATUS nt_status = NT_STATUS_OK;
 123         *error_string = NULL;
 124         switch (delta->delta_type) {
 125         case NETR_DELTA_USER:
 126         {
 127                 nt_status = fix_user(mem_ctx,
 128                                      creds,
 129                                      database,
 130                                      delta,
 131                                      error_string);
 132                 break;
 133         }
 134         case NETR_DELTA_SECRET:
 135         {
 136                 nt_status = fix_secret(mem_ctx,
 137                                        creds,
 138                                        database,
 139                                        delta,
 140                                        error_string);
 141                 break;
 142         }
 143         default:
 144                 break;
 145         }
 146         return nt_status;
 147 }
 148
 149 NTSTATUS libnet_SamSync_netlogon(struct libnet_context *ctx, TALLOC_CTX *mem_ctx, struct libnet_SamSync *r)
 150 {
 151         NTSTATUS nt_status, dbsync_nt_status;
 152         TALLOC_CTX *samsync_ctx, *loop_ctx, *delta_ctx;
 153         struct creds_CredentialState *creds;
 154         struct netr_DatabaseSync dbsync;
 155         struct cli_credentials *machine_account;
 156         struct dcerpc_pipe *p;
 157         struct libnet_context *machine_net_ctx;
 158         struct libnet_RpcConnectDCInfo *c;
 159         struct libnet_SamSync_state *state;
 160         const enum netr_SamDatabaseID database_ids[] = {SAM_DATABASE_DOMAIN, SAM_DATABASE_BUILTIN, SAM_DATABASE_PRIVS};
 161         int i;
 162
 163         samsync_ctx = talloc_named(mem_ctx, 0, "SamSync top context");
 164
 165         if (!r->in.machine_account) {
 166                 machine_account = cli_credentials_init(samsync_ctx);
 167                 if (!machine_account) {
 168                         talloc_free(samsync_ctx);
 169                         return NT_STATUS_NO_MEMORY;
 170                 }
 171                 cli_credentials_set_conf(machine_account);
 172                 nt_status = cli_credentials_set_machine_account(machine_account);
 173                 if (!NT_STATUS_IS_OK(nt_status)) {
 174                         r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain machine account password - are we joined to the domain?");
 175                         talloc_free(samsync_ctx);
 176                         return nt_status;
 177                 }
 178         } else {
 179                 machine_account = r->in.machine_account;
 180         }
 181
 182         /* We cannot do this unless we are a BDC.  Check, before we get odd errors later */
 183         if (cli_credentials_get_secure_channel_type(machine_account) != SEC_CHAN_BDC) {
 184                 r->out.error_string
 185                         = talloc_asprintf(mem_ctx,
 186                                           "Our join to domain %s is not as a BDC (%d), please rejoin as a BDC",
 187
 188                                           cli_credentials_get_domain(machine_account),
 189                                           cli_credentials_get_secure_channel_type(machine_account));
 190                 talloc_free(samsync_ctx);
 191                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 192         }
 193
 194         c = talloc(samsync_ctx, struct libnet_RpcConnectDCInfo);
 195         if (!c) {
 196                 r->out.error_string = NULL;
 197                 talloc_free(samsync_ctx);
 198                 return NT_STATUS_NO_MEMORY;
 199         }
 200
 201         if (r->in.binding_string) {
 202                 c->level      = LIBNET_RPC_CONNECT_BINDING;
 203                 c->in.binding = r->in.binding_string;
 204         } else {
 205                 /* prepare connect to the NETLOGON pipe of PDC */
 206                 c->level      = LIBNET_RPC_CONNECT_PDC;
 207                 c->in.name    = cli_credentials_get_domain(machine_account);
 208         }
 209         c->in.dcerpc_iface      = &dcerpc_table_netlogon;
 210
 211         /* We must do this as the machine, not as any command-line
 212          * user.  So we override the credentials in the
 213          * libnet_context */
 214         machine_net_ctx = talloc(samsync_ctx, struct libnet_context);
 215         if (!machine_net_ctx) {
 216                 r->out.error_string = NULL;
 217                 talloc_free(samsync_ctx);
 218                 return NT_STATUS_NO_MEMORY;
 219         }
 220         *machine_net_ctx = *ctx;
 221         machine_net_ctx->cred = machine_account;
 222
 223         /* connect to the NETLOGON pipe of the PDC */
 224         nt_status = libnet_RpcConnectDCInfo(machine_net_ctx, c);
 225         if (!NT_STATUS_IS_OK(nt_status)) {
 226                 if (r->in.binding_string) {
 227                         r->out.error_string = talloc_asprintf(mem_ctx,
 228                                                               "Connection to NETLOGON pipe of DC %s failed: %s",
 229                                                               r->in.binding_string, c->out.error_string);
 230                 } else {
 231                         r->out.error_string = talloc_asprintf(mem_ctx,
 232                                                               "Connection to NETLOGON pipe of DC for %s failed: %s",
 233                                                               c->in.name, c->out.error_string);
 234                 }
 235                 talloc_free(samsync_ctx);
 236                 return nt_status;
 237         }
 238
 239         /* This makes a new pipe, on which we can do schannel.  We
 240          * should do this in the RpcConnect code, but the abstaction
 241          * layers do not suit yet */
 242
 243         nt_status = dcerpc_secondary_connection(c->out.dcerpc_pipe, &p,
 244                                                 c->out.dcerpc_pipe->binding);
 245
 246         if (!NT_STATUS_IS_OK(nt_status)) {
 247                 r->out.error_string = talloc_asprintf(mem_ctx,
 248                                                       "Secondary connection to NETLOGON pipe of DC %s failed: %s",
 249                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 250                 talloc_free(samsync_ctx);
 251                 return nt_status;
 252         }
 253
 254         nt_status = dcerpc_bind_auth_schannel(samsync_ctx, p, &dcerpc_table_netlogon,
 255                                               machine_account, DCERPC_AUTH_LEVEL_PRIVACY);
 256
 257         if (!NT_STATUS_IS_OK(nt_status)) {
 258                 r->out.error_string = talloc_asprintf(mem_ctx,
 259                                                       "SCHANNEL authentication to NETLOGON pipe of DC %s failed: %s",
 260                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 261                 talloc_free(samsync_ctx);
 262                 return nt_status;
 263         }
 264
 265         state = talloc(samsync_ctx, struct libnet_SamSync_state);
 266         if (!state) {
 267                 r->out.error_string = NULL;
 268                 talloc_free(samsync_ctx);
 269                 return nt_status;
 270         }
 271
 272         state->domain_name     = c->out.domain_name;
 273         state->domain_sid      = c->out.domain_sid;
 274         state->realm           = c->out.realm;
 275         state->domain_guid     = c->out.guid;
 276         state->machine_net_ctx = machine_net_ctx;
 277         state->netlogon_pipe   = p;
 278
 279         /* initialise the callback layer.  It may wish to contact the
 280          * server with ldap, now we know the name */
 281
 282         if (r->in.init_fn) {
 283                 char *error_string;
 284                 nt_status = r->in.init_fn(samsync_ctx,
 285                                           r->in.fn_ctx,
 286                                           state,
 287                                           &error_string);
 288                 if (!NT_STATUS_IS_OK(nt_status)) {
 289                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 290                         talloc_free(samsync_ctx);
 291                         return nt_status;
 292                 }
 293         }
 294
 295         /* get NETLOGON credentails */
 296
 297         nt_status = dcerpc_schannel_creds(p->conn->security_state.generic_state, samsync_ctx, &creds);
 298         if (!NT_STATUS_IS_OK(nt_status)) {
 299                 r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain NETLOGON credentials from DCERPC/GENSEC layer");
 300                 talloc_free(samsync_ctx);
 301                 return nt_status;
 302         }
 303
 304         /* Setup details for the syncronisation */
 305         dbsync.in.logon_server = talloc_asprintf(samsync_ctx, "\\\\%s", dcerpc_server_name(p));
 306         dbsync.in.computername = cli_credentials_get_workstation(machine_account);
 307         dbsync.in.preferredmaximumlength = (uint32_t)-1;
 308         ZERO_STRUCT(dbsync.in.return_authenticator);
 309
 310         for (i=0;i< ARRAY_SIZE(database_ids); i++) {
 311                 dbsync.in.sync_context = 0;
 312                 dbsync.in.database_id = database_ids[i];
 313
 314                 do {
 315                         int d;
 316                         loop_ctx = talloc_named(samsync_ctx, 0, "DatabaseSync loop context");
 317                         creds_client_authenticator(creds, &dbsync.in.credential);
 318
 319                         dbsync_nt_status = dcerpc_netr_DatabaseSync(p, loop_ctx, &dbsync);
 320                         if (!NT_STATUS_IS_OK(dbsync_nt_status) &&
 321                             !NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES)) {
 322                                 r->out.error_string = talloc_asprintf(mem_ctx, "DatabaseSync failed - %s", nt_errstr(nt_status));
 323                                 talloc_free(samsync_ctx);
 324                                 return nt_status;
 325                         }
 326
 327                         if (!creds_client_check(creds, &dbsync.out.return_authenticator.cred)) {
 328                                 r->out.error_string = talloc_strdup(mem_ctx, "Credential chaining on incoming DatabaseSync failed");
 329                                 talloc_free(samsync_ctx);
 330                                 return NT_STATUS_ACCESS_DENIED;
 331                         }
 332
 333                         dbsync.in.sync_context = dbsync.out.sync_context;
 334
 335                         /* For every single remote 'delta' entry: */
 336                         for (d=0; d < dbsync.out.delta_enum_array->num_deltas; d++) {
 337                                 char *error_string = NULL;
 338                                 delta_ctx = talloc_named(loop_ctx, 0, "DatabaseSync delta context");
 339                                 /* 'Fix' elements, by decrypting and
 340                                  * de-obfustiating the data */
 341                                 nt_status = fix_delta(delta_ctx,
 342                                                       creds,
 343                                                       dbsync.in.database_id,
 344                                                       &dbsync.out.delta_enum_array->delta_enum[d],
 345                                                       &error_string);
 346                                 if (!NT_STATUS_IS_OK(nt_status)) {
 347                                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 348                                         talloc_free(samsync_ctx);
 349                                         return nt_status;
 350                                 }
 351
 352                                 /* Now call the callback.  This will
 353                                  * do something like print the data or
 354                                  * write to an ldb */
 355                                 nt_status = r->in.delta_fn(delta_ctx,
 356                                                            r->in.fn_ctx,
 357                                                            dbsync.in.database_id,
 358                                                            &dbsync.out.delta_enum_array->delta_enum[d],
 359                                                            &error_string);
 360                                 if (!NT_STATUS_IS_OK(nt_status)) {
 361                                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 362                                         talloc_free(samsync_ctx);
 363                                         return nt_status;
 364                                 }
 365                                 talloc_free(delta_ctx);
 366                         }
 367                         talloc_free(loop_ctx);
 368                 } while (NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES));
 369
 370                 if (!NT_STATUS_IS_OK(dbsync_nt_status)) {
 371                         r->out.error_string = talloc_asprintf(mem_ctx, "libnet_SamSync_netlogon failed: unexpected inconsistancy. Should not get error %s here", nt_errstr(nt_status));
 372                         talloc_free(samsync_ctx);
 373                         return dbsync_nt_status;
 374                 }
 375                 nt_status = NT_STATUS_OK;
 376         }
 377         talloc_free(samsync_ctx);
 378         return nt_status;
 379 }
 380