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 cli_credentials *machine_account;
 173         struct dcerpc_pipe *p;
 174         struct libnet_context *machine_net_ctx;
 175         struct libnet_RpcConnect *c;
 176         struct libnet_SamSync_state *state;
 177         const enum netr_SamDatabaseID database_ids[] = {SAM_DATABASE_DOMAIN, SAM_DATABASE_BUILTIN, SAM_DATABASE_PRIVS};
 178         int i;
 179
 180         samsync_ctx = talloc_named(mem_ctx, 0, "SamSync top context");
 181
 182         if (!r->in.machine_account) {
 183                 machine_account = cli_credentials_init(samsync_ctx);
 184                 if (!machine_account) {
 185                         talloc_free(samsync_ctx);
 186                         return NT_STATUS_NO_MEMORY;
 187                 }
 188                 cli_credentials_set_conf(machine_account, ctx->lp_ctx);
 189                 nt_status = cli_credentials_set_machine_account(machine_account, ctx->lp_ctx);
 190                 if (!NT_STATUS_IS_OK(nt_status)) {
 191                         r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain machine account password - are we joined to the domain?");
 192                         talloc_free(samsync_ctx);
 193                         return nt_status;
 194                 }
 195         } else {
 196                 machine_account = r->in.machine_account;
 197         }
 198
 199         /* We cannot do this unless we are a BDC.  Check, before we get odd errors later */
 200         if (cli_credentials_get_secure_channel_type(machine_account) != SEC_CHAN_BDC) {
 201                 r->out.error_string
 202                         = talloc_asprintf(mem_ctx,
 203                                           "Our join to domain %s is not as a BDC (%d), please rejoin as a BDC",
 204                                           cli_credentials_get_domain(machine_account),
 205                                           cli_credentials_get_secure_channel_type(machine_account));
 206                 talloc_free(samsync_ctx);
 207                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 208         }
 209
 210         c = talloc(samsync_ctx, struct libnet_RpcConnect);
 211         if (!c) {
 212                 r->out.error_string = NULL;
 213                 talloc_free(samsync_ctx);
 214                 return NT_STATUS_NO_MEMORY;
 215         }
 216
 217         c->level              = LIBNET_RPC_CONNECT_DC_INFO;
 218         if (r->in.binding_string) {
 219                 c->in.binding = r->in.binding_string;
 220                 c->in.name    = NULL;
 221         } else {
 222                 c->in.binding = NULL;
 223                 c->in.name    = cli_credentials_get_domain(machine_account);
 224         }
 225
 226         /* prepare connect to the NETLOGON pipe of PDC */
 227         c->in.dcerpc_iface      = &ndr_table_netlogon;
 228
 229         /* We must do this as the machine, not as any command-line
 230          * user.  So we override the credentials in the
 231          * libnet_context */
 232         machine_net_ctx = talloc(samsync_ctx, struct libnet_context);
 233         if (!machine_net_ctx) {
 234                 r->out.error_string = NULL;
 235                 talloc_free(samsync_ctx);
 236                 return NT_STATUS_NO_MEMORY;
 237         }
 238         *machine_net_ctx = *ctx;
 239         machine_net_ctx->cred = machine_account;
 240
 241         /* connect to the NETLOGON pipe of the PDC */
 242         nt_status = libnet_RpcConnect(machine_net_ctx, samsync_ctx, c);
 243         if (!NT_STATUS_IS_OK(nt_status)) {
 244                 if (r->in.binding_string) {
 245                         r->out.error_string = talloc_asprintf(mem_ctx,
 246                                                               "Connection to NETLOGON pipe of DC %s failed: %s",
 247                                                               r->in.binding_string, c->out.error_string);
 248                 } else {
 249                         r->out.error_string = talloc_asprintf(mem_ctx,
 250                                                               "Connection to NETLOGON pipe of DC for %s failed: %s",
 251                                                               c->in.name, c->out.error_string);
 252                 }
 253                 talloc_free(samsync_ctx);
 254                 return nt_status;
 255         }
 256
 257         /* This makes a new pipe, on which we can do schannel.  We
 258          * should do this in the RpcConnect code, but the abstaction
 259          * layers do not suit yet */
 260
 261         nt_status = dcerpc_secondary_connection(c->out.dcerpc_pipe, &p,
 262                                                 c->out.dcerpc_pipe->binding);
 263
 264         if (!NT_STATUS_IS_OK(nt_status)) {
 265                 r->out.error_string = talloc_asprintf(mem_ctx,
 266                                                       "Secondary connection to NETLOGON pipe of DC %s failed: %s",
 267                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 268                 talloc_free(samsync_ctx);
 269                 return nt_status;
 270         }
 271
 272         nt_status = dcerpc_bind_auth_schannel(samsync_ctx, p, &ndr_table_netlogon,
 273                                               machine_account, ctx->lp_ctx, DCERPC_AUTH_LEVEL_PRIVACY);
 274
 275         if (!NT_STATUS_IS_OK(nt_status)) {
 276                 r->out.error_string = talloc_asprintf(mem_ctx,
 277                                                       "SCHANNEL authentication to NETLOGON pipe of DC %s failed: %s",
 278                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 279                 talloc_free(samsync_ctx);
 280                 return nt_status;
 281         }
 282
 283         state = talloc(samsync_ctx, struct libnet_SamSync_state);
 284         if (!state) {
 285                 r->out.error_string = NULL;
 286                 talloc_free(samsync_ctx);
 287                 return nt_status;
 288         }
 289
 290         state->domain_name     = c->out.domain_name;
 291         state->domain_sid      = c->out.domain_sid;
 292         state->realm           = c->out.realm;
 293         state->domain_guid     = c->out.guid;
 294         state->machine_net_ctx = machine_net_ctx;
 295         state->netlogon_pipe   = p;
 296
 297         /* initialise the callback layer.  It may wish to contact the
 298          * server with ldap, now we know the name */
 299
 300         if (r->in.init_fn) {
 301                 char *error_string;
 302                 nt_status = r->in.init_fn(samsync_ctx,
 303                                           r->in.fn_ctx,
 304                                           state,
 305                                           &error_string);
 306                 if (!NT_STATUS_IS_OK(nt_status)) {
 307                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 308                         talloc_free(samsync_ctx);
 309                         return nt_status;
 310                 }
 311         }
 312
 313         /* get NETLOGON credentials */
 314
 315         nt_status = dcerpc_schannel_creds(p->conn->security_state.generic_state, samsync_ctx, &creds);
 316         if (!NT_STATUS_IS_OK(nt_status)) {
 317                 r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain NETLOGON credentials from DCERPC/GENSEC layer");
 318                 talloc_free(samsync_ctx);
 319                 return nt_status;
 320         }
 321
 322         /* Setup details for the synchronisation */
 323         dbsync.in.logon_server = talloc_asprintf(samsync_ctx, "\\\\%s", dcerpc_server_name(p));
 324         dbsync.in.computername = cli_credentials_get_workstation(machine_account);
 325         dbsync.in.preferredmaximumlength = (uint32_t)-1;
 326         ZERO_STRUCT(dbsync.in.return_authenticator);
 327
 328         for (i=0;i< ARRAY_SIZE(database_ids); i++) {
 329                 dbsync.in.sync_context = 0;
 330                 dbsync.in.database_id = database_ids[i];
 331
 332                 do {
 333                         int d;
 334                         loop_ctx = talloc_named(samsync_ctx, 0, "DatabaseSync loop context");
 335                         creds_client_authenticator(creds, &dbsync.in.credential);
 336
 337                         dbsync_nt_status = dcerpc_netr_DatabaseSync(p, loop_ctx, &dbsync);
 338                         if (!NT_STATUS_IS_OK(dbsync_nt_status) &&
 339                             !NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES)) {
 340                                 r->out.error_string = talloc_asprintf(mem_ctx, "DatabaseSync failed - %s", nt_errstr(nt_status));
 341                                 talloc_free(samsync_ctx);
 342                                 return nt_status;
 343                         }
 344
 345                         if (!creds_client_check(creds, &dbsync.out.return_authenticator.cred)) {
 346                                 r->out.error_string = talloc_strdup(mem_ctx, "Credential chaining on incoming DatabaseSync failed");
 347                                 talloc_free(samsync_ctx);
 348                                 return NT_STATUS_ACCESS_DENIED;
 349                         }
 350
 351                         dbsync.in.sync_context = dbsync.out.sync_context;
 352
 353                         /* For every single remote 'delta' entry: */
 354                         for (d=0; d < dbsync.out.delta_enum_array->num_deltas; d++) {
 355                                 char *error_string = NULL;
 356                                 delta_ctx = talloc_named(loop_ctx, 0, "DatabaseSync delta context");
 357                                 /* 'Fix' elements, by decrypting and
 358                                  * de-obfuscating the data */
 359                                 nt_status = fix_delta(delta_ctx,
 360                                                       creds,
 361                                                       r->in.rid_crypt,
 362                                                       dbsync.in.database_id,
 363                                                       &dbsync.out.delta_enum_array->delta_enum[d],
 364                                                       &error_string);
 365                                 if (!NT_STATUS_IS_OK(nt_status)) {
 366                                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 367                                         talloc_free(samsync_ctx);
 368                                         return nt_status;
 369                                 }
 370
 371                                 /* Now call the callback.  This will
 372                                  * do something like print the data or
 373                                  * write to an ldb */
 374                                 nt_status = r->in.delta_fn(delta_ctx,
 375                                                            r->in.fn_ctx,
 376                                                            dbsync.in.database_id,
 377                                                            &dbsync.out.delta_enum_array->delta_enum[d],
 378                                                            &error_string);
 379                                 if (!NT_STATUS_IS_OK(nt_status)) {
 380                                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 381                                         talloc_free(samsync_ctx);
 382                                         return nt_status;
 383                                 }
 384                                 talloc_free(delta_ctx);
 385                         }
 386                         talloc_free(loop_ctx);
 387                 } while (NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES));
 388
 389                 if (!NT_STATUS_IS_OK(dbsync_nt_status)) {
 390                         r->out.error_string = talloc_asprintf(mem_ctx, "libnet_SamSync_netlogon failed: unexpected inconsistancy. Should not get error %s here", nt_errstr(nt_status));
 391                         talloc_free(samsync_ctx);
 392                         return dbsync_nt_status;
 393                 }
 394                 nt_status = NT_STATUS_OK;
 395         }
 396         talloc_free(samsync_ctx);
 397         return nt_status;
 398 }
 399