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