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