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 "../libcli/samsync/samsync.h"
  27 #include "auth/gensec/gensec.h"
  28 #include "auth/gensec/schannel.h"
  29 #include "auth/credentials/credentials.h"
  30 #include "libcli/auth/schannel.h"
  31 #include "librpc/gen_ndr/ndr_netlogon.h"
  32 #include "librpc/gen_ndr/ndr_netlogon_c.h"
  33 #include "param/param.h"
  34
  35 NTSTATUS libnet_SamSync_netlogon(struct libnet_context *ctx, TALLOC_CTX *mem_ctx, struct libnet_SamSync *r)
  36 {
  37         NTSTATUS nt_status, dbsync_nt_status;
  38         TALLOC_CTX *samsync_ctx, *loop_ctx, *delta_ctx;
  39         struct netlogon_creds_CredentialState *creds;
  40         struct netr_DatabaseSync dbsync;
  41         struct netr_Authenticator credential, return_authenticator;
  42         struct netr_DELTA_ENUM_ARRAY *delta_enum_array = NULL;
  43         struct cli_credentials *machine_account;
  44         struct dcerpc_pipe *p;
  45         struct libnet_context *machine_net_ctx;
  46         struct libnet_RpcConnect *c;
  47         struct libnet_SamSync_state *state;
  48         const enum netr_SamDatabaseID database_ids[] = {SAM_DATABASE_DOMAIN, SAM_DATABASE_BUILTIN, SAM_DATABASE_PRIVS};
  49         unsigned int i;
  50
  51         samsync_ctx = talloc_named(mem_ctx, 0, "SamSync top context");
  52
  53         if (!r->in.machine_account) {
  54                 machine_account = cli_credentials_init(samsync_ctx);
  55                 if (!machine_account) {
  56                         talloc_free(samsync_ctx);
  57                         return NT_STATUS_NO_MEMORY;
  58                 }
  59                 cli_credentials_set_conf(machine_account, ctx->lp_ctx);
  60                 nt_status = cli_credentials_set_machine_account(machine_account, ctx->lp_ctx);
  61                 if (!NT_STATUS_IS_OK(nt_status)) {
  62                         r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain machine account password - are we joined to the domain?");
  63                         talloc_free(samsync_ctx);
  64                         return nt_status;
  65                 }
  66         } else {
  67                 machine_account = r->in.machine_account;
  68         }
  69
  70         /* We cannot do this unless we are a BDC.  Check, before we get odd errors later */
  71         if (cli_credentials_get_secure_channel_type(machine_account) != SEC_CHAN_BDC) {
  72                 r->out.error_string
  73                         = talloc_asprintf(mem_ctx,
  74                                           "Our join to domain %s is not as a BDC (%d), please rejoin as a BDC",
  75                                           cli_credentials_get_domain(machine_account),
  76                                           cli_credentials_get_secure_channel_type(machine_account));
  77                 talloc_free(samsync_ctx);
  78                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
  79         }
  80
  81         c = talloc_zero(samsync_ctx, struct libnet_RpcConnect);
  82         if (!c) {
  83                 r->out.error_string = NULL;
  84                 talloc_free(samsync_ctx);
  85                 return NT_STATUS_NO_MEMORY;
  86         }
  87
  88         c->level              = LIBNET_RPC_CONNECT_DC_INFO;
  89         if (r->in.binding_string) {
  90                 c->in.binding = r->in.binding_string;
  91                 c->in.name    = NULL;
  92         } else {
  93                 c->in.binding = NULL;
  94                 c->in.name    = cli_credentials_get_domain(machine_account);
  95         }
  96
  97         /* prepare connect to the NETLOGON pipe of PDC */
  98         c->in.dcerpc_iface      = &ndr_table_netlogon;
  99
 100         /* We must do this as the machine, not as any command-line
 101          * user.  So we override the credentials in the
 102          * libnet_context */
 103         machine_net_ctx = talloc(samsync_ctx, struct libnet_context);
 104         if (!machine_net_ctx) {
 105                 r->out.error_string = NULL;
 106                 talloc_free(samsync_ctx);
 107                 return NT_STATUS_NO_MEMORY;
 108         }
 109         *machine_net_ctx = *ctx;
 110         machine_net_ctx->cred = machine_account;
 111
 112         /* connect to the NETLOGON pipe of the PDC */
 113         nt_status = libnet_RpcConnect(machine_net_ctx, samsync_ctx, c);
 114         if (!NT_STATUS_IS_OK(nt_status)) {
 115                 if (r->in.binding_string) {
 116                         r->out.error_string = talloc_asprintf(mem_ctx,
 117                                                               "Connection to NETLOGON pipe of DC %s failed: %s",
 118                                                               r->in.binding_string, c->out.error_string);
 119                 } else {
 120                         r->out.error_string = talloc_asprintf(mem_ctx,
 121                                                               "Connection to NETLOGON pipe of DC for %s failed: %s",
 122                                                               c->in.name, c->out.error_string);
 123                 }
 124                 talloc_free(samsync_ctx);
 125                 return nt_status;
 126         }
 127
 128         /* This makes a new pipe, on which we can do schannel.  We
 129          * should do this in the RpcConnect code, but the abstaction
 130          * layers do not suit yet */
 131
 132         nt_status = dcerpc_secondary_connection(c->out.dcerpc_pipe, &p,
 133                                                 c->out.dcerpc_pipe->binding);
 134
 135         if (!NT_STATUS_IS_OK(nt_status)) {
 136                 r->out.error_string = talloc_asprintf(mem_ctx,
 137                                                       "Secondary connection to NETLOGON pipe of DC %s failed: %s",
 138                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 139                 talloc_free(samsync_ctx);
 140                 return nt_status;
 141         }
 142
 143         nt_status = dcerpc_bind_auth_schannel(samsync_ctx, p, &ndr_table_netlogon,
 144                                               machine_account, ctx->lp_ctx, DCERPC_AUTH_LEVEL_PRIVACY);
 145
 146         if (!NT_STATUS_IS_OK(nt_status)) {
 147                 r->out.error_string = talloc_asprintf(mem_ctx,
 148                                                       "SCHANNEL authentication to NETLOGON pipe of DC %s failed: %s",
 149                                                       dcerpc_server_name(p), nt_errstr(nt_status));
 150                 talloc_free(samsync_ctx);
 151                 return nt_status;
 152         }
 153
 154         state = talloc(samsync_ctx, struct libnet_SamSync_state);
 155         if (!state) {
 156                 r->out.error_string = NULL;
 157                 talloc_free(samsync_ctx);
 158                 return nt_status;
 159         }
 160
 161         state->domain_name     = c->out.domain_name;
 162         state->domain_sid      = c->out.domain_sid;
 163         state->realm           = c->out.realm;
 164         state->domain_guid     = c->out.guid;
 165         state->machine_net_ctx = machine_net_ctx;
 166         state->netlogon_pipe   = p;
 167
 168         /* initialise the callback layer.  It may wish to contact the
 169          * server with ldap, now we know the name */
 170
 171         if (r->in.init_fn) {
 172                 char *error_string;
 173                 nt_status = r->in.init_fn(samsync_ctx,
 174                                           r->in.fn_ctx,
 175                                           state,
 176                                           &error_string);
 177                 if (!NT_STATUS_IS_OK(nt_status)) {
 178                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 179                         talloc_free(samsync_ctx);
 180                         return nt_status;
 181                 }
 182         }
 183
 184         /* get NETLOGON credentials */
 185
 186         nt_status = dcerpc_schannel_creds(p->conn->security_state.generic_state, samsync_ctx, &creds);
 187         if (!NT_STATUS_IS_OK(nt_status)) {
 188                 r->out.error_string = talloc_strdup(mem_ctx, "Could not obtain NETLOGON credentials from DCERPC/GENSEC layer");
 189                 talloc_free(samsync_ctx);
 190                 return nt_status;
 191         }
 192
 193         /* Setup details for the synchronisation */
 194
 195         ZERO_STRUCT(return_authenticator);
 196
 197         dbsync.in.logon_server = talloc_asprintf(samsync_ctx, "\\\\%s", dcerpc_server_name(p));
 198         dbsync.in.computername = cli_credentials_get_workstation(machine_account);
 199         dbsync.in.preferredmaximumlength = (uint32_t)-1;
 200         dbsync.in.return_authenticator = &return_authenticator;
 201         dbsync.out.return_authenticator = &return_authenticator;
 202         dbsync.out.delta_enum_array = &delta_enum_array;
 203
 204         for (i=0;i< ARRAY_SIZE(database_ids); i++) {
 205
 206                 uint32_t sync_context = 0;
 207
 208                 dbsync.in.database_id = database_ids[i];
 209                 dbsync.in.sync_context = &sync_context;
 210                 dbsync.out.sync_context = &sync_context;
 211
 212                 do {
 213                         uint32_t d;
 214                         loop_ctx = talloc_named(samsync_ctx, 0, "DatabaseSync loop context");
 215                         netlogon_creds_client_authenticator(creds, &credential);
 216
 217                         dbsync.in.credential = &credential;
 218
 219                         dbsync_nt_status = dcerpc_netr_DatabaseSync_r(p->binding_handle, loop_ctx, &dbsync);
 220                         if (NT_STATUS_IS_OK(dbsync_nt_status) && !NT_STATUS_IS_OK(dbsync.out.result)) {
 221                                 dbsync_nt_status = dbsync.out.result;
 222                         }
 223                         if (!NT_STATUS_IS_OK(dbsync_nt_status) &&
 224                             !NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES)) {
 225                                 r->out.error_string = talloc_asprintf(mem_ctx, "DatabaseSync failed - %s", nt_errstr(nt_status));
 226                                 talloc_free(samsync_ctx);
 227                                 return nt_status;
 228                         }
 229
 230                         if (!netlogon_creds_client_check(creds, &dbsync.out.return_authenticator->cred)) {
 231                                 r->out.error_string = talloc_strdup(mem_ctx, "Credential chaining on incoming DatabaseSync failed");
 232                                 talloc_free(samsync_ctx);
 233                                 return NT_STATUS_ACCESS_DENIED;
 234                         }
 235
 236                         dbsync.in.sync_context = dbsync.out.sync_context;
 237
 238                         /* For every single remote 'delta' entry: */
 239                         for (d=0; d < delta_enum_array->num_deltas; d++) {
 240                                 char *error_string = NULL;
 241                                 delta_ctx = talloc_named(loop_ctx, 0, "DatabaseSync delta context");
 242                                 /* 'Fix' elements, by decrypting and
 243                                  * de-obfuscating the data */
 244                                 nt_status = samsync_fix_delta(delta_ctx,
 245                                                               creds,
 246                                                               dbsync.in.database_id,
 247                                                               &delta_enum_array->delta_enum[d]);
 248                                 if (!NT_STATUS_IS_OK(nt_status)) {
 249                                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 250                                         talloc_free(samsync_ctx);
 251                                         return nt_status;
 252                                 }
 253
 254                                 /* Now call the callback.  This will
 255                                  * do something like print the data or
 256                                  * write to an ldb */
 257                                 nt_status = r->in.delta_fn(delta_ctx,
 258                                                            r->in.fn_ctx,
 259                                                            dbsync.in.database_id,
 260                                                            &delta_enum_array->delta_enum[d],
 261                                                            &error_string);
 262                                 if (!NT_STATUS_IS_OK(nt_status)) {
 263                                         r->out.error_string = talloc_steal(mem_ctx, error_string);
 264                                         talloc_free(samsync_ctx);
 265                                         return nt_status;
 266                                 }
 267                                 talloc_free(delta_ctx);
 268                         }
 269                         talloc_free(loop_ctx);
 270                 } while (NT_STATUS_EQUAL(dbsync_nt_status, STATUS_MORE_ENTRIES));
 271
 272                 if (!NT_STATUS_IS_OK(dbsync_nt_status)) {
 273                         r->out.error_string = talloc_asprintf(mem_ctx, "libnet_SamSync_netlogon failed: unexpected inconsistency. Should not get error %s here", nt_errstr(dbsync_nt_status));
 274                         talloc_free(samsync_ctx);
 275                         return dbsync_nt_status;
 276                 }
 277                 nt_status = NT_STATUS_OK;
 278         }
 279         talloc_free(samsync_ctx);
 280         return nt_status;
 281 }
 282