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