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