source4/auth/credentials/credentials_files.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 "lib/ldb/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 "../lib/util/util_ldb.h"
  31 #include "auth/credentials/credentials.h"
  32 #include "auth/credentials/credentials_krb5.h"
  33 #include "auth/credentials/credentials_proto.h"
  34 #include "param/param.h"
  35 #include "lib/events/events.h"
  36 #include "dsdb/samdb/samdb.h"
  37
  38
  39 /**
  40  * Read a file descriptor, and parse it for a password (eg from a file or stdin)
  41  *
  42  * @param credentials Credentials structure on which to set the password
  43  * @param fd open file descriptor to read the password from
  44  * @param obtained This enum describes how 'specified' this password is
  45  */
  46
  47 _PUBLIC_ bool cli_credentials_parse_password_fd(struct cli_credentials *credentials,
  48                                        int fd, enum credentials_obtained obtained)
  49 {
  50         char *p;
  51         char pass[128];
  52
  53         for(p = pass, *p = '\0'; /* ensure that pass is null-terminated */
  54                 p && p - pass < sizeof(pass);) {
  55                 switch (read(fd, p, 1)) {
  56                 case 1:
  57                         if (*p != '\n' && *p != '\0') {
  58                                 *++p = '\0'; /* advance p, and null-terminate pass */
  59                                 break;
  60                         }
  61                         /* fall through */
  62                 case 0:
  63                         if (p - pass) {
  64                                 *p = '\0'; /* null-terminate it, just in case... */
  65                                 p = NULL; /* then force the loop condition to become false */
  66                                 break;
  67                         } else {
  68                                 fprintf(stderr, "Error reading password from file descriptor %d: %s\n", fd, "empty password\n");
  69                                 return false;
  70                         }
  71
  72                 default:
  73                         fprintf(stderr, "Error reading password from file descriptor %d: %s\n",
  74                                         fd, strerror(errno));
  75                         return false;
  76                 }
  77         }
  78
  79         cli_credentials_set_password(credentials, pass, obtained);
  80         return true;
  81 }
  82
  83 /**
  84  * Read a named file, and parse it for a password
  85  *
  86  * @param credentials Credentials structure on which to set the password
  87  * @param file a named file to read the password from
  88  * @param obtained This enum describes how 'specified' this password is
  89  */
  90
  91 _PUBLIC_ bool cli_credentials_parse_password_file(struct cli_credentials *credentials, const char *file, enum credentials_obtained obtained)
  92 {
  93         int fd = open(file, O_RDONLY, 0);
  94         bool ret;
  95
  96         if (fd < 0) {
  97                 fprintf(stderr, "Error opening password file %s: %s\n",
  98                                 file, strerror(errno));
  99                 return false;
 100         }
 101
 102         ret = cli_credentials_parse_password_fd(credentials, fd, obtained);
 103
 104         close(fd);
 105
 106         return ret;
 107 }
 108
 109 /**
 110  * Read a named file, and parse it for username, domain, realm and password
 111  *
 112  * @param credentials Credentials structure on which to set the password
 113  * @param file a named file to read the details from
 114  * @param obtained This enum describes how 'specified' this password is
 115  */
 116
 117 _PUBLIC_ bool cli_credentials_parse_file(struct cli_credentials *cred, const char *file, enum credentials_obtained obtained)
 118 {
 119         uint16_t len = 0;
 120         char *ptr, *val, *param;
 121         char **lines;
 122         int i, numlines;
 123
 124         lines = file_lines_load(file, &numlines, 0, NULL);
 125
 126         if (lines == NULL)
 127         {
 128                 /* fail if we can't open the credentials file */
 129                 d_printf("ERROR: Unable to open credentials file!\n");
 130                 return false;
 131         }
 132
 133         for (i = 0; i < numlines; i++) {
 134                 len = strlen(lines[i]);
 135
 136                 if (len == 0)
 137                         continue;
 138
 139                 /* break up the line into parameter & value.
 140                  * will need to eat a little whitespace possibly */
 141                 param = lines[i];
 142                 if (!(ptr = strchr_m (lines[i], '=')))
 143                         continue;
 144
 145                 val = ptr+1;
 146                 *ptr = '\0';
 147
 148                 /* eat leading white space */
 149                 while ((*val!='\0') && ((*val==' ') || (*val=='\t')))
 150                         val++;
 151
 152                 if (strwicmp("password", param) == 0) {
 153                         cli_credentials_set_password(cred, val, obtained);
 154                 } else if (strwicmp("username", param) == 0) {
 155                         cli_credentials_set_username(cred, val, obtained);
 156                 } else if (strwicmp("domain", param) == 0) {
 157                         cli_credentials_set_domain(cred, val, obtained);
 158                 } else if (strwicmp("realm", param) == 0) {
 159                         cli_credentials_set_realm(cred, val, obtained);
 160                 }
 161                 memset(lines[i], 0, len);
 162         }
 163
 164         talloc_free(lines);
 165
 166         return true;
 167 }
 168
 169
 170 /**
 171  * Fill in credentials for the machine trust account, from the secrets database.
 172  *
 173  * @param cred Credentials structure to fill in
 174  * @retval NTSTATUS error detailing any failure
 175  */
 176 _PUBLIC_ NTSTATUS cli_credentials_set_secrets(struct cli_credentials *cred,
 177                                               struct tevent_context *event_ctx,
 178                                               struct loadparm_context *lp_ctx,
 179                                               struct ldb_context *ldb,
 180                                               const char *base,
 181                                               const char *filter,
 182                                               char **error_string)
 183 {
 184         TALLOC_CTX *mem_ctx;
 185
 186         int ldb_ret;
 187         struct ldb_message *msg;
 188         const char *attrs[] = {
 189                 "secret",
 190                 "priorSecret",
 191                 "samAccountName",
 192                 "flatname",
 193                 "realm",
 194                 "secureChannelType",
 195                 "unicodePwd",
 196                 "msDS-KeyVersionNumber",
 197                 "saltPrincipal",
 198                 "privateKeytab",
 199                 "krb5Keytab",
 200                 "servicePrincipalName",
 201                 "ldapBindDn",
 202                 NULL
 203         };
 204
 205         const char *machine_account;
 206         const char *password;
 207         const char *old_password;
 208         const char *domain;
 209         const char *realm;
 210         enum netr_SchannelType sct;
 211         const char *salt_principal;
 212         const char *keytab;
 213
 214         /* ok, we are going to get it now, don't recurse back here */
 215         cred->machine_account_pending = false;
 216
 217         /* some other parts of the system will key off this */
 218         cred->machine_account = true;
 219
 220         mem_ctx = talloc_named(cred, 0, "cli_credentials fetch machine password");
 221
 222         if (!ldb) {
 223                 /* Local secrets are stored in secrets.ldb */
 224                 ldb = secrets_db_connect(mem_ctx, event_ctx, lp_ctx);
 225                 if (!ldb) {
 226                         /* set anonymous as the fallback, if the machine account won't work */
 227                         cli_credentials_set_anonymous(cred);
 228                         *error_string = talloc_strdup(cred, "Could not open secrets.ldb");
 229                         talloc_free(mem_ctx);
 230                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 231                 }
 232         }
 233
 234         ldb_ret = dsdb_search_one(ldb, ldb, &msg,
 235                                   ldb_dn_new(mem_ctx, ldb, base),
 236                                   LDB_SCOPE_SUBTREE,
 237                                   attrs, 0, "%s", filter);
 238
 239         if (ldb_ret != LDB_SUCCESS) {
 240                 *error_string = talloc_asprintf(cred, "Could not find entry to match filter: '%s' base: '%s': %s: %s\n",
 241                                                 filter, base ? base : "",
 242                                                 ldb_strerror(ldb_ret), ldb_errstring(ldb));
 243                 /* set anonymous as the fallback, if the machine account won't work */
 244                 cli_credentials_set_anonymous(cred);
 245                 talloc_free(mem_ctx);
 246                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 247         }
 248
 249         password = ldb_msg_find_attr_as_string(msg, "secret", NULL);
 250         old_password = ldb_msg_find_attr_as_string(msg, "priorSecret", NULL);
 251
 252         machine_account = ldb_msg_find_attr_as_string(msg, "samAccountName", NULL);
 253
 254         if (!machine_account) {
 255                 machine_account = ldb_msg_find_attr_as_string(msg, "servicePrincipalName", NULL);
 256
 257                 if (!machine_account) {
 258                         const char *ldap_bind_dn = ldb_msg_find_attr_as_string(msg, "ldapBindDn", NULL);
 259                         if (!ldap_bind_dn) {
 260                                 *error_string = talloc_asprintf(cred,
 261                                                                 "Could not find 'samAccountName', "
 262                                                                 "'servicePrincipalName' or "
 263                                                                 "'ldapBindDn' in secrets record: %s",
 264                                                                 ldb_dn_get_linearized(msg->dn));
 265                                 /* set anonymous as the fallback, if the machine account won't work */
 266                                 cli_credentials_set_anonymous(cred);
 267                                 talloc_free(mem_ctx);
 268                                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 269                         } else {
 270                                 /* store bind dn in credentials */
 271                                 cli_credentials_set_bind_dn(cred, ldap_bind_dn);
 272                         }
 273                 }
 274         }
 275
 276         salt_principal = ldb_msg_find_attr_as_string(msg, "saltPrincipal", NULL);
 277         cli_credentials_set_salt_principal(cred, salt_principal);
 278
 279         sct = ldb_msg_find_attr_as_int(msg, "secureChannelType", 0);
 280         if (sct) {
 281                 cli_credentials_set_secure_channel_type(cred, sct);
 282         }
 283
 284         if (!password) {
 285                 const struct ldb_val *nt_password_hash = ldb_msg_find_ldb_val(msg, "unicodePwd");
 286                 struct samr_Password hash;
 287                 ZERO_STRUCT(hash);
 288                 if (nt_password_hash) {
 289                         memcpy(hash.hash, nt_password_hash->data,
 290                                MIN(nt_password_hash->length, sizeof(hash.hash)));
 291
 292                         cli_credentials_set_nt_hash(cred, &hash, CRED_SPECIFIED);
 293                 } else {
 294                         cli_credentials_set_password(cred, NULL, CRED_SPECIFIED);
 295                 }
 296         } else {
 297                 cli_credentials_set_password(cred, password, CRED_SPECIFIED);
 298         }
 299
 300
 301         domain = ldb_msg_find_attr_as_string(msg, "flatname", NULL);
 302         if (domain) {
 303                 cli_credentials_set_domain(cred, domain, CRED_SPECIFIED);
 304         }
 305
 306         realm = ldb_msg_find_attr_as_string(msg, "realm", NULL);
 307         if (realm) {
 308                 cli_credentials_set_realm(cred, realm, CRED_SPECIFIED);
 309         }
 310
 311         if (machine_account) {
 312                 cli_credentials_set_username(cred, machine_account, CRED_SPECIFIED);
 313         }
 314
 315         cli_credentials_set_kvno(cred, ldb_msg_find_attr_as_int(msg, "msDS-KeyVersionNumber", 0));
 316
 317         /* If there was an external keytab specified by reference in
 318          * the LDB, then use this.  Otherwise we will make one up
 319          * (chewing CPU time) from the password */
 320         keytab = ldb_msg_find_attr_as_string(msg, "krb5Keytab", NULL);
 321         if (keytab) {
 322                 cli_credentials_set_keytab_name(cred, event_ctx, lp_ctx, keytab, CRED_SPECIFIED);
 323         } else {
 324                 keytab = ldb_msg_find_attr_as_string(msg, "privateKeytab", NULL);
 325                 if (keytab) {
 326                         keytab = talloc_asprintf(mem_ctx, "FILE:%s", samdb_relative_path(ldb, mem_ctx, keytab));
 327                         if (keytab) {
 328                                 cli_credentials_set_keytab_name(cred, event_ctx, lp_ctx, keytab, CRED_SPECIFIED);
 329                         }
 330                 }
 331         }
 332         talloc_free(mem_ctx);
 333
 334         return NT_STATUS_OK;
 335 }
 336
 337 /**
 338  * Fill in credentials for the machine trust account, from the secrets database.
 339  *
 340  * @param cred Credentials structure to fill in
 341  * @retval NTSTATUS error detailing any failure
 342  */
 343 _PUBLIC_ NTSTATUS cli_credentials_set_machine_account(struct cli_credentials *cred,
 344                                                       struct loadparm_context *lp_ctx)
 345 {
 346         NTSTATUS status;
 347         char *filter;
 348         char *error_string;
 349         /* Bleh, nasty recursion issues: We are setting a machine
 350          * account here, so we don't want the 'pending' flag around
 351          * any more */
 352         cred->machine_account_pending = false;
 353         filter = talloc_asprintf(cred, SECRETS_PRIMARY_DOMAIN_FILTER,
 354                                        cli_credentials_get_domain(cred));
 355         status = cli_credentials_set_secrets(cred, event_context_find(cred), lp_ctx, NULL,
 356                                            SECRETS_PRIMARY_DOMAIN_DN,
 357                                              filter, &error_string);
 358         if (!NT_STATUS_IS_OK(status)) {
 359                 DEBUG(1, ("Could not find machine account in secrets database: %s: %s", nt_errstr(status), error_string));
 360                 talloc_free(error_string);
 361         }
 362         return status;
 363 }
 364
 365 /**
 366  * Fill in credentials for the machine trust account, from the secrets database.
 367  *
 368  * @param cred Credentials structure to fill in
 369  * @retval NTSTATUS error detailing any failure
 370  */
 371 NTSTATUS cli_credentials_set_krbtgt(struct cli_credentials *cred,
 372                                     struct tevent_context *event_ctx,
 373                                     struct loadparm_context *lp_ctx)
 374 {
 375         NTSTATUS status;
 376         char *filter;
 377         char *error_string;
 378         /* Bleh, nasty recursion issues: We are setting a machine
 379          * account here, so we don't want the 'pending' flag around
 380          * any more */
 381         cred->machine_account_pending = false;
 382         filter = talloc_asprintf(cred, SECRETS_KRBTGT_SEARCH,
 383                                        cli_credentials_get_realm(cred),
 384                                        cli_credentials_get_domain(cred));
 385         status = cli_credentials_set_secrets(cred, event_ctx, lp_ctx, NULL,
 386                                              SECRETS_PRINCIPALS_DN,
 387                                              filter, &error_string);
 388         if (!NT_STATUS_IS_OK(status)) {
 389                 DEBUG(1, ("Could not find krbtgt (master Kerberos) account in secrets database: %s: %s", nt_errstr(status), error_string));
 390                 talloc_free(error_string);
 391         }
 392         return status;
 393 }
 394
 395 /**
 396  * Fill in credentials for a particular prinicpal, from the secrets database.
 397  *
 398  * @param cred Credentials structure to fill in
 399  * @retval NTSTATUS error detailing any failure
 400  */
 401 _PUBLIC_ NTSTATUS cli_credentials_set_stored_principal(struct cli_credentials *cred,
 402                                                        struct tevent_context *event_ctx,
 403                                               struct loadparm_context *lp_ctx,
 404                                               const char *serviceprincipal)
 405 {
 406         NTSTATUS status;
 407         char *filter;
 408         char *error_string;
 409         /* Bleh, nasty recursion issues: We are setting a machine
 410          * account here, so we don't want the 'pending' flag around
 411          * any more */
 412         cred->machine_account_pending = false;
 413         filter = talloc_asprintf(cred, SECRETS_PRINCIPAL_SEARCH,
 414                                  cli_credentials_get_realm(cred),
 415                                  cli_credentials_get_domain(cred),
 416                                  serviceprincipal);
 417         status = cli_credentials_set_secrets(cred, event_ctx, lp_ctx, NULL,
 418                                              SECRETS_PRINCIPALS_DN, filter,
 419                                              &error_string);
 420         if (!NT_STATUS_IS_OK(status)) {
 421                 DEBUG(1, ("Could not find %s principal in secrets database: %s: %s", serviceprincipal, nt_errstr(status), error_string));
 422         }
 423         return status;
 424 }
 425
 426 /**
 427  * Ask that when required, the credentials system will be filled with
 428  * machine trust account, from the secrets database.
 429  *
 430  * @param cred Credentials structure to fill in
 431  * @note This function is used to call the above function after, rather
 432  *       than during, popt processing.
 433  *
 434  */
 435 _PUBLIC_ void cli_credentials_set_machine_account_pending(struct cli_credentials *cred,
 436                                                  struct loadparm_context *lp_ctx)
 437 {
 438         cred->machine_account_pending = true;
 439         cred->machine_account_pending_lp_ctx = lp_ctx;
 440 }
 441
 442