source/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 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
  32
  33 /**
  34  * Decrypt and extract the user's passwords.
  35  *
  36  * The writes decrypted (no longer 'RID encrypted' or arcfour encrypted) passwords back into the structure
  37  */
  38 static NTSTATUS fix_user(TALLOC_CTX *mem_ctx,
  39                          struct creds_CredentialState *creds,
  40                          bool rid_crypt,
  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 (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                 data.data = user->user_private_info.SensitiveData;
  69                 data.length = user->user_private_info.DataLength;
  70                 creds_arcfour_crypt(creds, data.data, data.length);
  71                 user->user_private_info.SensitiveData = data.data;
  72                 user->user_private_info.DataLength = data.length;
  73
  74                 nt_status = ndr_pull_struct_blob(&data, mem_ctx, &keys, (ndr_pull_flags_fn_t)ndr_pull_netr_USER_KEYS);
  75                 if (NT_STATUS_IS_OK(nt_status)) {
  76                         if (keys.keys.keys2.lmpassword.length == 16) {
  77                                 if (rid_crypt) {
  78                                         sam_rid_crypt(rid, keys.keys.keys2.lmpassword.pwd.hash, lm_hash.hash, 0);
  79                                         user->lmpassword = lm_hash;
  80                                 } else {
  81                                         user->lmpassword = keys.keys.keys2.lmpassword.pwd;
  82                                 }
  83                                 user->lm_password_present = True;
  84                         }
  85                         if (keys.keys.keys2.ntpassword.length == 16) {
  86                                 if (rid_crypt) {
  87                                         sam_rid_crypt(rid, keys.keys.keys2.ntpassword.pwd.hash, nt_hash.hash, 0);
  88                                         user->ntpassword = nt_hash;
  89                                 } else {
  90                                         user->ntpassword = keys.keys.keys2.ntpassword.pwd;
  91                                 }
  92                                 user->nt_password_present = True;
  93                         }
  94                         /* TODO: rid decrypt history fields */
  95                 } else {
  96                         *error_string = talloc_asprintf(mem_ctx, "Failed to parse Sensitive Data for %s:", username);
  97                         dump_data(10, data.data, data.length);
  98                         return nt_status;
  99                 }
 100         }
 101         return NT_STATUS_OK;
 102 }
 103
 104 /**
 105  * Decrypt and extract the secrets
 106  *
 107  * The writes decrypted secrets back into the structure
 108  */
 109 static NTSTATUS fix_secret(TALLOC_CTX *mem_ctx,
 110                            struct creds_CredentialState *creds,
 111                            enum netr_SamDatabaseID database,
 112                            struct netr_DELTA_ENUM *delta,
 113                            char **error_string)
 114 {
 115         struct netr_DELTA_SECRET *secret = delta->delta_union.secret;
 116         creds_arcfour_crypt(creds, secret->current_cipher.cipher_data,
 117                             secret->current_cipher.maxlen);
 118
 119         creds_arcfour_crypt(creds, secret->old_cipher.cipher_data,
 120                             secret->old_cipher.maxlen);
 121
 122         return NT_STATUS_OK;
 123 }
 124
 125 /**
 126  * Fix up the delta, dealing with encryption issues so that the final
 127  * callback need only do the printing or application logic
 128  */
 129
 130 static NTSTATUS fix_delta(TALLOC_CTX *mem_ctx,
 131                           struct creds_CredentialState *creds,
 132                           bool rid_crypt,
 133                           enum netr_SamDatabaseID database,
 134                           struct netr_DELTA_ENUM *delta,
 135                           char **error_string)
 136 {
 137         NTSTATUS nt_status = NT_STATUS_OK;
 138         *error_string = NULL;
 139         switch (delta->delta_type) {
 140         case NETR_DELTA_USER:
 141         {
 142                 nt_status = fix_user(mem_ctx,
 143                                      creds,
 144                                      rid_crypt,
 145                                      database,
 146                                      delta,
 147                                      error_string);
 148                 break;
 149         }
 150         case NETR_DELTA_SECRET:
 151         {
 152                 nt_status = fix_secret(mem_ctx,
 153                                        creds,
 154                                        database,
 155                                        delta,
 156                                        error_string);
 157                 break;
 158         }
 159         default:
 160                 break;
 161         }
 162         return nt_status;
 163 }
 164
 165 NTSTATUS libnet_SamSync_netlogon(struct libnet_context *ctx, TALLOC_CTX *mem_ctx, struct libnet_SamSync *r)
 166 {
 167         NTSTATUS nt_status, dbsync_nt_status;
 168         TALLOC_CTX *samsync_ctx, *loop_ctx, *delta_ctx;
 169         struct creds_CredentialState *creds;
 170         struct netr_DatabaseSync dbsync;
 171         struct cli_credentials *machine_account;
 172         struct dcerpc_pipe *p;
 173         struct libnet_context *machine_net_ctx;
 174         struct libnet_RpcConnect *c;
 175         struct libnet_SamSync_state *state;
 176         const enum netr_SamDatabaseID database_ids[] = {SAM_DATABASE_DOMAIN, SAM_DATABASE_BUILTIN, SAM_DATABASE_PRIVS};
 177         int i;
 178
 179         samsync_ctx = talloc_named(mem_ctx, 0, "SamSync top context");
 180
 181         if (!r->in.machine_account) {
 182                 machine_account = cli_credentials_init(samsync_ctx);
 183                 if (!machine_account) {
 184                         talloc_free(samsync_ctx);
 185                         return NT_STATUS_NO_MEMORY;
 186                 }
 187                 cli_credentials_set_conf(machine_account);
 188                 nt_status = cli_credentials_set_machine_account(machine_account);
 189                 if (!NT_STATUS_IS_OK(nt_status)) {
 190                         r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain machine account password - are we joined to the domain?");
 191                         talloc_free(samsync_ctx);
 192                         return nt_status;
 193                 }
 194         } else {
 195                 machine_account = r->in.machine_account;
 196         }
 197
 198         /* We cannot do this unless we are a BDC.  Check, before we get odd errors later */
 199         if (cli_credentials_get_secure_channel_type(machine_account) != SEC_CHAN_BDC) {
 200                 r->out.error_string
 201                         = talloc_asprintf(mem_ctx,
 202                                           "Our join to domain %s is not as a BDC (%d), please rejoin as a BDC",
 203                                           cli_credentials_get_domain(machine_account),
 204                                           cli_credentials_get_secure_channel_type(machine_account));
 205                 talloc_free(samsync_ctx);
 206                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 207         }
 208
 209         c = talloc(samsync_ctx, struct libnet_RpcConnect);
 210         if (!c) {
 211                 r->out.error_string = NULL;
 212                 talloc_free(samsync_ctx);
 213                 return NT_STATUS_NO_MEMORY;
 214         }
 215
 216         c->level              = LIBNET_RPC_CONNECT_DC_INFO;
 217         if (r->in.binding_string) {
 218                 c->in.binding = r->in.binding_string;
 219                 c->in.name    = NULL;
 220         } else {
 221                 c->in.binding = NULL;
 222                 c->in.name    = cli_credentials_get_domain(machine_account);
 223         }
 224
 225         /* prepare connect to the NETLOGON pipe of PDC */
 226         c->in.dcerpc_iface      = &ndr_table_netlogon;
 227
 228         /* We must do this as the machine, not as any command-line
 229          * user.  So we override the credentials in the
 230          * libnet_context */
 231         machine_net_ctx = talloc(samsync_ctx, struct libnet_context);
 232         if (!machine_net_ctx) {
 233                 r->out.error_string = NULL;
 234                 talloc_free(samsync_ctx);
 235                 return NT_STATUS_NO_MEMORY;
 236         }
 237         *machine_net_ctx = *ctx;
 238         machine_net_ctx->cred = machine_account;
 239
 240         /* connect to the NETLOGON pipe of the PDC */
 241         nt_status = libnet_RpcConnect(machine_net_ctx, samsync_ctx, c);
 242         if (!NT_STATUS_IS_OK(nt_status)) {
 243                 if (r->in.binding_string) {
 244                         r->out.error_string = talloc_asprintf(mem_ctx,
 245                                                               "Connection to NETLOGON pipe of DC %s failed: %s",
 246                                                               r->in.binding_string, c->out.error_string);
 247                 } else {
 248                         r->out.error_string = talloc_asprintf(mem_ctx,
 249                                                               "Connection to NETLOGON pipe of DC for %s failed: %s",
 250                                                               c->in.name, c->out.error_string);
 251                 }
 252                 talloc_free(samsync_ctx);
 253                 return nt_status;
 254         }
 255
 256         /* This makes a new pipe, on which we can do schannel.  We
 257          * should do this in the RpcConnect code, but the abstaction
 258          * layers do not suit yet */
 259
 260         nt_status = dcerpc_secondary_connection(c->out.dcerpc_pipe, &p,
 261                                                 c->out.dcerpc_pipe->binding);
 262
 263         if (!NT_STATUS_IS_OK(nt_status)) {
 264                 r->out.error_string = talloc_asprintf(mem_ctx,
 265                                                       "Secondary connection to NETLOGON pipe of DC %s failed: %s",
 266                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 267                 talloc_free(samsync_ctx);
 268                 return nt_status;
 269         }
 270
 271         nt_status = dcerpc_bind_auth_schannel(samsync_ctx, p, &ndr_table_netlogon,
 272                                               machine_account, DCERPC_AUTH_LEVEL_PRIVACY);
 273
 274         if (!NT_STATUS_IS_OK(nt_status)) {
 275                 r->out.error_string = talloc_asprintf(mem_ctx,
 276                                                       "SCHANNEL authentication to NETLOGON pipe of DC %s failed: %s",
 277                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 278                 talloc_free(samsync_ctx);
 279                 return nt_status;
 280         }
 281
 282         state = talloc(samsync_ctx, struct libnet_SamSync_state);
 283         if (!state) {
 284                 r->out.error_string = NULL;
 285                 talloc_free(samsync_ctx);
 286                 return nt_status;
 287         }
 288
 289         state->domain_name     = c->out.domain_name;
 290         state->domain_sid      = c->out.domain_sid;
 291         state->realm           = c->out.realm;
 292         state->domain_guid     = c->out.guid;
 293         state->machine_net_ctx = machine_net_ctx;
 294         state->netlogon_pipe   = p;
 295
 296         /* initialise the callback layer.  It may wish to contact the
 297          * server with ldap, now we know the name */
 298
 299         if (r->in.init_fn) {
 300                 char *error_string;
 301                 nt_status = r->in.init_fn(samsync_ctx,
 302                                           r->in.fn_ctx,
 303                                           state,
 304                                           &error_string);
 305                 if (!NT_STATUS_IS_OK(nt_status)) {
 306                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 307                         talloc_free(samsync_ctx);
 308                         return nt_status;
 309                 }
 310         }
 311
 312         /* get NETLOGON credentails */
 313
 314         nt_status = dcerpc_schannel_creds(p->conn->security_state.generic_state, samsync_ctx, &creds);
 315         if (!NT_STATUS_IS_OK(nt_status)) {
 316                 r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain NETLOGON credentials from DCERPC/GENSEC layer");
 317                 talloc_free(samsync_ctx);
 318                 return nt_status;
 319         }
 320
 321         /* Setup details for the synchronisation */
 322         dbsync.in.logon_server = talloc_asprintf(samsync_ctx, "\\\\%s", dcerpc_server_name(p));
 323         dbsync.in.computername = cli_credentials_get_workstation(machine_account);
 324         dbsync.in.preferredmaximumlength = (uint32_t)-1;
 325         ZERO_STRUCT(dbsync.in.return_authenticator);
 326
 327         for (i=0;i< ARRAY_SIZE(database_ids); i++) {
 328                 dbsync.in.sync_context = 0;
 329                 dbsync.in.database_id = database_ids[i];
 330
 331                 do {
 332                         int d;
 333                         loop_ctx = talloc_named(samsync_ctx, 0, "DatabaseSync loop context");
 334                         creds_client_authenticator(creds, &dbsync.in.credential);
 335
 336                         dbsync_nt_status = dcerpc_netr_DatabaseSync(p, loop_ctx, &dbsync);
 337                         if (!NT_STATUS_IS_OK(dbsync_nt_status) &&
 338                             !NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES)) {
 339                                 r->out.error_string = talloc_asprintf(mem_ctx, "DatabaseSync failed - %s", nt_errstr(nt_status));
 340                                 talloc_free(samsync_ctx);
 341                                 return nt_status;
 342                         }
 343
 344                         if (!creds_client_check(creds, &dbsync.out.return_authenticator.cred)) {
 345                                 r->out.error_string = talloc_strdup(mem_ctx, "Credential chaining on incoming DatabaseSync failed");
 346                                 talloc_free(samsync_ctx);
 347                                 return NT_STATUS_ACCESS_DENIED;
 348                         }
 349
 350                         dbsync.in.sync_context = dbsync.out.sync_context;
 351
 352                         /* For every single remote 'delta' entry: */
 353                         for (d=0; d < dbsync.out.delta_enum_array->num_deltas; d++) {
 354                                 char *error_string = NULL;
 355                                 delta_ctx = talloc_named(loop_ctx, 0, "DatabaseSync delta context");
 356                                 /* 'Fix' elements, by decrypting and
 357                                  * de-obfuscating the data */
 358                                 nt_status = fix_delta(delta_ctx,
 359                                                       creds,
 360                                                       r->in.rid_crypt,
 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
 370                                 /* Now call the callback.  This will
 371                                  * do something like print the data or
 372                                  * write to an ldb */
 373                                 nt_status = r->in.delta_fn(delta_ctx,
 374                                                            r->in.fn_ctx,
 375                                                            dbsync.in.database_id,
 376                                                            &dbsync.out.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                                 talloc_free(delta_ctx);
 384                         }
 385                         talloc_free(loop_ctx);
 386                 } while (NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES));
 387
 388                 if (!NT_STATUS_IS_OK(dbsync_nt_status)) {
 389                         r->out.error_string = talloc_asprintf(mem_ctx, "libnet_SamSync_netlogon failed: unexpected inconsistancy. Should not get error %s here", nt_errstr(nt_status));
 390                         talloc_free(samsync_ctx);
 391                         return dbsync_nt_status;
 392                 }
 393                 nt_status = NT_STATUS_OK;
 394         }
 395         talloc_free(samsync_ctx);
 396         return nt_status;
 397 }
 398