auth/credentials/credentials_secrets.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    User credentials handling (as regards on-disk files)
   5
   6    Copyright (C) Jelmer Vernooij 2005
   7    Copyright (C) Tim Potter 2001
   8    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "lib/events/events.h"
  26 #include <ldb.h>
  27 #include "librpc/gen_ndr/samr.h" /* for struct samrPassword */
  28 #include "param/secrets.h"
  29 #include "system/filesys.h"
  30 #include "auth/credentials/credentials.h"
  31 #include "auth/credentials/credentials_proto.h"
  32 #include "auth/credentials/credentials_krb5.h"
  33 #include "auth/kerberos/kerberos_util.h"
  34 #include "param/param.h"
  35 #include "lib/events/events.h"
  36 #include "dsdb/samdb/samdb.h"
  37 #include "source3/include/secrets.h"
  38 #include "dbwrap/dbwrap.h"
  39 #include "dbwrap/dbwrap_open.h"
  40 #include "lib/util/util_tdb.h"
  41
  42
  43 /**
  44  * Fill in credentials for the machine trust account, from the secrets database.
  45  *
  46  * @param cred Credentials structure to fill in
  47  * @retval NTSTATUS error detailing any failure
  48  */
  49 _PUBLIC_ NTSTATUS cli_credentials_set_secrets(struct cli_credentials *cred,
  50                                               struct loadparm_context *lp_ctx,
  51                                               struct ldb_context *ldb,
  52                                               const char *base,
  53                                               const char *filter,
  54                                               char **error_string)
  55 {
  56         TALLOC_CTX *mem_ctx;
  57
  58         int ldb_ret;
  59         struct ldb_message *msg;
  60
  61         const char *machine_account;
  62         const char *password;
  63         const char *domain;
  64         const char *realm;
  65         enum netr_SchannelType sct;
  66         const char *salt_principal;
  67         char *keytab;
  68         const struct ldb_val *whenChanged;
  69
  70         /* ok, we are going to get it now, don't recurse back here */
  71         cred->machine_account_pending = false;
  72
  73         /* some other parts of the system will key off this */
  74         cred->machine_account = true;
  75
  76         mem_ctx = talloc_named(cred, 0, "cli_credentials fetch machine password");
  77
  78         if (!ldb) {
  79                 /* Local secrets are stored in secrets.ldb */
  80                 ldb = secrets_db_connect(mem_ctx, lp_ctx);
  81                 if (!ldb) {
  82                         /* set anonymous as the fallback, if the machine account won't work */
  83                         cli_credentials_set_anonymous(cred);
  84                         *error_string = talloc_strdup(cred, "Could not open secrets.ldb");
  85                         talloc_free(mem_ctx);
  86                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
  87                 }
  88         }
  89
  90         ldb_ret = dsdb_search_one(ldb, mem_ctx, &msg,
  91                                   ldb_dn_new(mem_ctx, ldb, base),
  92                                   LDB_SCOPE_SUBTREE,
  93                                   NULL, 0, "%s", filter);
  94
  95         if (ldb_ret != LDB_SUCCESS) {
  96                 *error_string = talloc_asprintf(cred, "Could not find entry to match filter: '%s' base: '%s': %s: %s",
  97                                                 filter, base ? base : "",
  98                                                 ldb_strerror(ldb_ret), ldb_errstring(ldb));
  99                 /* set anonymous as the fallback, if the machine account won't work */
 100                 cli_credentials_set_anonymous(cred);
 101                 talloc_free(mem_ctx);
 102                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 103         }
 104
 105         password = ldb_msg_find_attr_as_string(msg, "secret", NULL);
 106
 107         machine_account = ldb_msg_find_attr_as_string(msg, "samAccountName", NULL);
 108
 109         if (!machine_account) {
 110                 machine_account = ldb_msg_find_attr_as_string(msg, "servicePrincipalName", NULL);
 111
 112                 if (!machine_account) {
 113                         const char *ldap_bind_dn = ldb_msg_find_attr_as_string(msg, "ldapBindDn", NULL);
 114                         if (!ldap_bind_dn) {
 115                                 *error_string = talloc_asprintf(cred,
 116                                                                 "Could not find 'samAccountName', "
 117                                                                 "'servicePrincipalName' or "
 118                                                                 "'ldapBindDn' in secrets record: %s",
 119                                                                 ldb_dn_get_linearized(msg->dn));
 120                                 /* set anonymous as the fallback, if the machine account won't work */
 121                                 cli_credentials_set_anonymous(cred);
 122                                 talloc_free(mem_ctx);
 123                                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 124                         } else {
 125                                 /* store bind dn in credentials */
 126                                 cli_credentials_set_bind_dn(cred, ldap_bind_dn);
 127                         }
 128                 }
 129         }
 130
 131         salt_principal = ldb_msg_find_attr_as_string(msg, "saltPrincipal", NULL);
 132         cli_credentials_set_salt_principal(cred, salt_principal);
 133
 134         sct = ldb_msg_find_attr_as_int(msg, "secureChannelType", 0);
 135         if (sct) {
 136                 cli_credentials_set_secure_channel_type(cred, sct);
 137         }
 138
 139         if (!password) {
 140                 const struct ldb_val *nt_password_hash = ldb_msg_find_ldb_val(msg, "unicodePwd");
 141                 struct samr_Password hash;
 142                 ZERO_STRUCT(hash);
 143                 if (nt_password_hash) {
 144                         memcpy(hash.hash, nt_password_hash->data,
 145                                MIN(nt_password_hash->length, sizeof(hash.hash)));
 146
 147                         cli_credentials_set_nt_hash(cred, &hash, CRED_SPECIFIED);
 148                 } else {
 149                         cli_credentials_set_password(cred, NULL, CRED_SPECIFIED);
 150                 }
 151         } else {
 152                 cli_credentials_set_password(cred, password, CRED_SPECIFIED);
 153         }
 154
 155
 156         domain = ldb_msg_find_attr_as_string(msg, "flatname", NULL);
 157         if (domain) {
 158                 cli_credentials_set_domain(cred, domain, CRED_SPECIFIED);
 159         }
 160
 161         realm = ldb_msg_find_attr_as_string(msg, "realm", NULL);
 162         if (realm) {
 163                 cli_credentials_set_realm(cred, realm, CRED_SPECIFIED);
 164         }
 165
 166         if (machine_account) {
 167                 cli_credentials_set_username(cred, machine_account, CRED_SPECIFIED);
 168         }
 169
 170         cli_credentials_set_kvno(cred, ldb_msg_find_attr_as_int(msg, "msDS-KeyVersionNumber", 0));
 171
 172         whenChanged = ldb_msg_find_ldb_val(msg, "whenChanged");
 173         if (whenChanged) {
 174                 time_t lct;
 175                 if (ldb_val_to_time(whenChanged, &lct) == LDB_SUCCESS) {
 176                         cli_credentials_set_password_last_changed_time(cred, lct);
 177                 }
 178         }
 179
 180         /* If there was an external keytab specified by reference in
 181          * the LDB, then use this.  Otherwise we will make one up
 182          * (chewing CPU time) from the password */
 183         keytab = keytab_name_from_msg(cred, ldb, msg);
 184         if (keytab) {
 185                 cli_credentials_set_keytab_name(cred, lp_ctx, keytab, CRED_SPECIFIED);
 186                 talloc_free(keytab);
 187         }
 188         talloc_free(mem_ctx);
 189
 190         return NT_STATUS_OK;
 191 }
 192
 193 /**
 194  * Fill in credentials for the machine trust account, from the secrets database.
 195  *
 196  * @param cred Credentials structure to fill in
 197  * @retval NTSTATUS error detailing any failure
 198  */
 199 _PUBLIC_ NTSTATUS cli_credentials_set_machine_account(struct cli_credentials *cred,
 200                                                       struct loadparm_context *lp_ctx)
 201 {
 202         NTSTATUS status;
 203         char *filter;
 204         char *error_string;
 205         const char *domain;
 206         /* Bleh, nasty recursion issues: We are setting a machine
 207          * account here, so we don't want the 'pending' flag around
 208          * any more */
 209         cred->machine_account_pending = false;
 210
 211         /* We have to do this, as the fallback in
 212          * cli_credentials_set_secrets is to run as anonymous, so the domain is wiped */
 213         domain = cli_credentials_get_domain(cred);
 214         filter = talloc_asprintf(cred, SECRETS_PRIMARY_DOMAIN_FILTER,
 215                                  domain);
 216         status = cli_credentials_set_secrets(cred, lp_ctx, NULL,
 217                                              SECRETS_PRIMARY_DOMAIN_DN,
 218                                              filter, &error_string);
 219         if (NT_STATUS_EQUAL(NT_STATUS_CANT_ACCESS_DOMAIN_INFO, status)
 220             || NT_STATUS_EQUAL(NT_STATUS_NOT_FOUND, status)) {
 221                 TDB_DATA dbuf;
 222                 char *secrets_tdb = lpcfg_private_path(cred, lp_ctx, "secrets.tdb");
 223                 struct db_context *db_ctx = dbwrap_local_open(cred, lp_ctx, secrets_tdb, 0,
 224                                                               TDB_DEFAULT, O_RDWR, 0600,
 225                                                               DBWRAP_LOCK_ORDER_1);
 226                 if (db_ctx) {
 227                         char *keystr;
 228                         char *keystr_upper;
 229                         keystr = talloc_asprintf(cred, "%s/%s",
 230                                                  SECRETS_MACHINE_PASSWORD,
 231                                                  domain);
 232                         keystr_upper = strupper_talloc(cred, keystr);
 233                         TALLOC_FREE(keystr);
 234                         status = dbwrap_fetch(db_ctx, cred, string_tdb_data(keystr_upper),
 235                                               &dbuf);
 236
 237                         if (NT_STATUS_IS_OK(status)) {
 238                                 char *machine_account = talloc_asprintf(cred, "%s$", lpcfg_netbios_name(lp_ctx));
 239                                 cli_credentials_set_password(cred, (const char *)dbuf.dptr, CRED_SPECIFIED);
 240                                 cli_credentials_set_domain(cred, domain, CRED_SPECIFIED);
 241                                 cli_credentials_set_username(cred, machine_account, CRED_SPECIFIED);
 242                                 TALLOC_FREE(machine_account);
 243                                 TALLOC_FREE(dbuf.dptr);
 244                         } else {
 245                                 error_string = talloc_asprintf(cred,
 246                                                                "Failed to fetch machine account password from "
 247                                                                "secrets.ldb: %s and failed to fetch %s from %s",
 248                                                                error_string, keystr_upper, secrets_tdb);
 249                         }
 250                         TALLOC_FREE(keystr_upper);
 251                         TALLOC_FREE(secrets_tdb);
 252                 }
 253         }
 254
 255         if (!NT_STATUS_IS_OK(status)) {
 256                 DEBUG(1, ("Could not find machine account in secrets database: %s: %s\n",
 257                           error_string, nt_errstr(status)));
 258                 talloc_free(error_string);
 259         }
 260         return status;
 261 }
 262
 263 /**
 264  * Fill in credentials for the machine trust account, from the secrets database.
 265  *
 266  * @param cred Credentials structure to fill in
 267  * @retval NTSTATUS error detailing any failure
 268  */
 269 NTSTATUS cli_credentials_set_krbtgt(struct cli_credentials *cred,
 270                                     struct loadparm_context *lp_ctx)
 271 {
 272         NTSTATUS status;
 273         char *filter;
 274         char *error_string;
 275         /* Bleh, nasty recursion issues: We are setting a machine
 276          * account here, so we don't want the 'pending' flag around
 277          * any more */
 278         cred->machine_account_pending = false;
 279         filter = talloc_asprintf(cred, SECRETS_KRBTGT_SEARCH,
 280                                        cli_credentials_get_realm(cred),
 281                                        cli_credentials_get_domain(cred));
 282         status = cli_credentials_set_secrets(cred, lp_ctx, NULL,
 283                                              SECRETS_PRINCIPALS_DN,
 284                                              filter, &error_string);
 285         if (!NT_STATUS_IS_OK(status)) {
 286                 DEBUG(1, ("Could not find krbtgt (master Kerberos) account in secrets database: %s: %s\n", nt_errstr(status), error_string));
 287                 talloc_free(error_string);
 288         }
 289         return status;
 290 }
 291
 292 /**
 293  * Fill in credentials for a particular prinicpal, from the secrets database.
 294  *
 295  * @param cred Credentials structure to fill in
 296  * @retval NTSTATUS error detailing any failure
 297  */
 298 _PUBLIC_ NTSTATUS cli_credentials_set_stored_principal(struct cli_credentials *cred,
 299                                               struct loadparm_context *lp_ctx,
 300                                               const char *serviceprincipal)
 301 {
 302         NTSTATUS status;
 303         char *filter;
 304         char *error_string;
 305         /* Bleh, nasty recursion issues: We are setting a machine
 306          * account here, so we don't want the 'pending' flag around
 307          * any more */
 308         cred->machine_account_pending = false;
 309         filter = talloc_asprintf(cred, SECRETS_PRINCIPAL_SEARCH,
 310                                  cli_credentials_get_realm(cred),
 311                                  cli_credentials_get_domain(cred),
 312                                  serviceprincipal);
 313         status = cli_credentials_set_secrets(cred, lp_ctx, NULL,
 314                                              SECRETS_PRINCIPALS_DN, filter,
 315                                              &error_string);
 316         if (!NT_STATUS_IS_OK(status)) {
 317                 DEBUG(1, ("Could not find %s principal in secrets database: %s: %s\n", serviceprincipal, nt_errstr(status), error_string));
 318         }
 319         return status;
 320 }
 321
 322 /**
 323  * Ask that when required, the credentials system will be filled with
 324  * machine trust account, from the secrets database.
 325  *
 326  * @param cred Credentials structure to fill in
 327  * @note This function is used to call the above function after, rather
 328  *       than during, popt processing.
 329  *
 330  */
 331 _PUBLIC_ void cli_credentials_set_machine_account_pending(struct cli_credentials *cred,
 332                                                  struct loadparm_context *lp_ctx)
 333 {
 334         cred->machine_account_pending = true;
 335         cred->machine_account_pending_lp_ctx = lp_ctx;
 336 }
 337
 338