source3/libsmb/trusts_util.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  Routines to operate on various trust relationships
   4  *  Copyright (C) Andrew Bartlett                   2001
   5  *  Copyright (C) Rafal Szczesniak                  2003
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 3 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "includes.h"
  22 #include "../libcli/auth/libcli_auth.h"
  23 #include "../libcli/auth/netlogon_creds_cli.h"
  24 #include "rpc_client/cli_netlogon.h"
  25 #include "rpc_client/cli_pipe.h"
  26 #include "../librpc/gen_ndr/ndr_netlogon.h"
  27 #include "secrets.h"
  28 #include "passdb.h"
  29 #include "libsmb/libsmb.h"
  30 #include "source3/include/messages.h"
  31 #include "source3/include/g_lock.h"
  32
  33 /*********************************************************
  34  Change the domain password on the PDC.
  35  Do most of the legwork ourselfs.  Caller must have
  36  already setup the connection to the NETLOGON pipe
  37 **********************************************************/
  38
  39 struct trust_pw_change_state {
  40         struct g_lock_ctx *g_ctx;
  41         char *g_lock_key;
  42 };
  43
  44 static int trust_pw_change_state_destructor(struct trust_pw_change_state *state)
  45 {
  46         g_lock_unlock(state->g_ctx, state->g_lock_key);
  47         return 0;
  48 }
  49
  50 NTSTATUS trust_pw_change(struct netlogon_creds_cli_context *context,
  51                          struct messaging_context *msg_ctx,
  52                          struct dcerpc_binding_handle *b,
  53                          const char *domain,
  54                          bool force)
  55 {
  56         TALLOC_CTX *frame = talloc_stackframe();
  57         struct trust_pw_change_state *state;
  58         struct cli_credentials *creds = NULL;
  59         const struct samr_Password *current_nt_hash = NULL;
  60         const struct samr_Password *previous_nt_hash = NULL;
  61         enum netr_SchannelType sec_channel_type = SEC_CHAN_NULL;
  62         time_t pass_last_set_time;
  63         uint32_t old_version = 0;
  64         struct pdb_trusted_domain *td = NULL;
  65         struct timeval g_timeout = { 0, };
  66         int timeout = 0;
  67         struct timeval tv = { 0, };
  68         size_t new_len = DEFAULT_TRUST_ACCOUNT_PASSWORD_LENGTH;
  69         uint8_t new_password_buffer[256 * 2] = { 0, };
  70         char *new_trust_passwd = NULL;
  71         size_t len = 0;
  72         uint32_t new_version = 0;
  73         uint32_t *new_trust_version = NULL;
  74         NTSTATUS status;
  75         bool ok;
  76
  77         state = talloc_zero(frame, struct trust_pw_change_state);
  78         if (state == NULL) {
  79                 TALLOC_FREE(frame);
  80                 return NT_STATUS_NO_MEMORY;
  81         }
  82
  83         state->g_ctx = g_lock_ctx_init(state, msg_ctx);
  84         if (state->g_ctx == NULL) {
  85                 TALLOC_FREE(frame);
  86                 return NT_STATUS_NO_MEMORY;
  87         }
  88
  89         state->g_lock_key = talloc_asprintf(state,
  90                                 "trust_password_change_%s",
  91                                 domain);
  92         if (state->g_lock_key == NULL) {
  93                 TALLOC_FREE(frame);
  94                 return NT_STATUS_NO_MEMORY;
  95         }
  96
  97         g_timeout = timeval_current_ofs(10, 0);
  98         status = g_lock_lock(state->g_ctx,
  99                              state->g_lock_key,
 100                              G_LOCK_WRITE, g_timeout);
 101         if (!NT_STATUS_IS_OK(status)) {
 102                 DEBUG(1, ("could not get g_lock on [%s]!\n",
 103                           state->g_lock_key));
 104                 TALLOC_FREE(frame);
 105                 return status;
 106         }
 107
 108         talloc_set_destructor(state, trust_pw_change_state_destructor);
 109
 110         status = pdb_get_trust_credentials(domain, NULL, frame, &creds);
 111         if (!NT_STATUS_IS_OK(status)) {
 112                 DEBUG(0, ("could not fetch domain creds for domain %s - %s!\n",
 113                           domain, nt_errstr(status)));
 114                 TALLOC_FREE(frame);
 115                 return NT_STATUS_TRUSTED_RELATIONSHIP_FAILURE;
 116         }
 117
 118         current_nt_hash = cli_credentials_get_nt_hash(creds, frame);
 119         if (current_nt_hash == NULL) {
 120                 DEBUG(0, ("cli_credentials_get_nt_hash failed for domain %s!\n",
 121                           domain));
 122                 TALLOC_FREE(frame);
 123                 return NT_STATUS_TRUSTED_RELATIONSHIP_FAILURE;
 124         }
 125
 126         old_version = cli_credentials_get_kvno(creds);
 127         pass_last_set_time = cli_credentials_get_password_last_changed_time(creds);
 128         sec_channel_type = cli_credentials_get_secure_channel_type(creds);
 129
 130         new_version = old_version + 1;
 131
 132         switch (sec_channel_type) {
 133         case SEC_CHAN_WKSTA:
 134         case SEC_CHAN_BDC:
 135                 break;
 136         case SEC_CHAN_DNS_DOMAIN:
 137                 /*
 138                  * new_len * 2 = 498 bytes is the largest possible length
 139                  * NL_PASSWORD_VERSION consumes the rest of the possible 512 bytes
 140                  * and a confounder with at least 2 bytes is required.
 141                  *
 142                  * Windows uses new_len = 120 => 240 bytes.
 143                  */
 144                 new_len = 120;
 145
 146                 /* fall through */
 147         case SEC_CHAN_DOMAIN:
 148                 status = pdb_get_trusted_domain(frame, domain, &td);
 149                 if (!NT_STATUS_IS_OK(status)) {
 150                         DEBUG(0, ("pdb_get_trusted_domain() failed for domain %s - %s!\n",
 151                                   domain, nt_errstr(status)));
 152                         TALLOC_FREE(frame);
 153                         return status;
 154                 }
 155
 156                 new_trust_version = &new_version;
 157                 break;
 158         default:
 159                 TALLOC_FREE(frame);
 160                 return NT_STATUS_NOT_SUPPORTED;
 161         }
 162
 163         timeout = lp_machine_password_timeout();
 164         if (timeout == 0) {
 165                 if (!force) {
 166                         DEBUG(10,("machine password never expires\n"));
 167                         TALLOC_FREE(frame);
 168                         return NT_STATUS_OK;
 169                 }
 170         }
 171
 172         tv.tv_sec = pass_last_set_time;
 173         DEBUG(10, ("password last changed %s\n",
 174                    timeval_string(talloc_tos(), &tv, false)));
 175         tv.tv_sec += timeout;
 176         DEBUGADD(10, ("password valid until %s\n",
 177                       timeval_string(talloc_tos(), &tv, false)));
 178
 179         if (!force && !timeval_expired(&tv)) {
 180                 TALLOC_FREE(frame);
 181                 return NT_STATUS_OK;
 182         }
 183
 184         /*
 185          * Create a random machine account password
 186          * We create a random buffer and convert that to utf8.
 187          * This is similar to what windows is doing.
 188          */
 189         generate_secret_buffer(new_password_buffer, new_len * 2);
 190         ok = convert_string_talloc(frame,
 191                                    CH_UTF16MUNGED, CH_UTF8,
 192                                    new_password_buffer, new_len * 2,
 193                                    (void *)&new_trust_passwd, &len);
 194         ZERO_STRUCT(new_password_buffer);
 195         if (!ok) {
 196                 DEBUG(0, ("convert_string_talloc failed\n"));
 197                 TALLOC_FREE(frame);
 198                 return NT_STATUS_NO_MEMORY;
 199         }
 200
 201         /*
 202          * We could use cli_credentials_get_old_nt_hash(creds, frame) to
 203          * set previous_nt_hash.
 204          *
 205          * But we want to check if the dc has our current password and only do
 206          * a change if that's the case. So we keep previous_nt_hash = NULL.
 207          *
 208          * TODO:
 209          * If the previous password is the only password in common with the dc,
 210          * we better skip the password change, or use something like
 211          * ServerTrustPasswordsGet() or netr_ServerGetTrustInfo() to fix our
 212          * local secrets before doing the change.
 213          */
 214         status = netlogon_creds_cli_auth(context, b,
 215                                          *current_nt_hash,
 216                                          previous_nt_hash);
 217         if (!NT_STATUS_IS_OK(status)) {
 218                 DEBUG(0, ("netlogon_creds_cli_auth for domain %s - %s!\n",
 219                           domain, nt_errstr(status)));
 220                 TALLOC_FREE(frame);
 221                 return status;
 222         }
 223
 224         /*
 225          * Return the result of trying to write the new password
 226          * back into the trust account file.
 227          */
 228
 229         switch (sec_channel_type) {
 230
 231         case SEC_CHAN_WKSTA:
 232         case SEC_CHAN_BDC:
 233                 ok = secrets_store_machine_password(new_trust_passwd, domain, sec_channel_type);
 234                 if (!ok) {
 235                         DEBUG(0, ("secrets_store_machine_password failed for domain %s!\n",
 236                                   domain));
 237                         TALLOC_FREE(frame);
 238                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
 239                 }
 240                 break;
 241
 242         case SEC_CHAN_DNS_DOMAIN:
 243         case SEC_CHAN_DOMAIN:
 244                 /*
 245                  * we need to get the sid first for the
 246                  * pdb_set_trusteddom_pw call
 247                  */
 248                 ok = pdb_set_trusteddom_pw(domain, new_trust_passwd,
 249                                            &td->security_identifier);
 250                 if (!ok) {
 251                         DEBUG(0, ("pdb_set_trusteddom_pw() failed for domain %s!\n",
 252                                   domain));
 253                         TALLOC_FREE(frame);
 254                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
 255                 }
 256                 break;
 257
 258         default:
 259                 smb_panic("Unsupported secure channel type");
 260                 break;
 261         }
 262
 263         DEBUG(1,("%s : %s(%s): Changed password locally\n",
 264                  current_timestring(talloc_tos(), false), __func__, domain));
 265
 266         status = netlogon_creds_cli_ServerPasswordSet(context, b,
 267                                                       new_trust_passwd,
 268                                                       new_trust_version);
 269         if (!NT_STATUS_IS_OK(status)) {
 270                 DEBUG(0,("%s : %s(%s) remote password change set failed - %s\n",
 271                          current_timestring(talloc_tos(), false), __func__,
 272                          domain, nt_errstr(status)));
 273                 TALLOC_FREE(frame);
 274                 return status;
 275         }
 276
 277         DEBUG(1,("%s : %s(%s): Changed password remotely.\n",
 278                  current_timestring(talloc_tos(), false), __func__, domain));
 279
 280         TALLOC_FREE(frame);
 281         return NT_STATUS_OK;
 282 }