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 2 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, write to the Free Software
  22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23 */
  24
  25 #include "includes.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 "db_wrap.h"
  31 #include "auth/credentials/credentials.h"
  32 #include "auth/credentials/credentials_krb5.h"
  33
  34 /**
  35  * Read a file descriptor, and parse it for a password (eg from a file or stdin)
  36  *
  37  * @param credentials Credentials structure on which to set the password
  38  * @param fd open file descriptor to read the password from
  39  * @param obtained This enum describes how 'specified' this password is
  40  */
  41
  42 BOOL cli_credentials_parse_password_fd(struct cli_credentials *credentials,
  43                                        int fd, enum credentials_obtained obtained)
  44 {
  45         char *p;
  46         char pass[128];
  47
  48         for(p = pass, *p = '\0'; /* ensure that pass is null-terminated */
  49                 p && p - pass < sizeof(pass);) {
  50                 switch (read(fd, p, 1)) {
  51                 case 1:
  52                         if (*p != '\n' && *p != '\0') {
  53                                 *++p = '\0'; /* advance p, and null-terminate pass */
  54                                 break;
  55                         }
  56                         /* fall through */
  57                 case 0:
  58                         if (p - pass) {
  59                                 *p = '\0'; /* null-terminate it, just in case... */
  60                                 p = NULL; /* then force the loop condition to become false */
  61                                 break;
  62                         } else {
  63                                 fprintf(stderr, "Error reading password from file descriptor %d: %s\n", fd, "empty password\n");
  64                                 return False;
  65                         }
  66
  67                 default:
  68                         fprintf(stderr, "Error reading password from file descriptor %d: %s\n",
  69                                         fd, strerror(errno));
  70                         return False;
  71                 }
  72         }
  73
  74         cli_credentials_set_password(credentials, pass, obtained);
  75         return True;
  76 }
  77
  78 /**
  79  * Read a named file, and parse it for a password
  80  *
  81  * @param credentials Credentials structure on which to set the password
  82  * @param file a named file to read the password from
  83  * @param obtained This enum describes how 'specified' this password is
  84  */
  85
  86 BOOL cli_credentials_parse_password_file(struct cli_credentials *credentials, const char *file, enum credentials_obtained obtained)
  87 {
  88         int fd = open(file, O_RDONLY, 0);
  89         BOOL ret;
  90
  91         if (fd < 0) {
  92                 fprintf(stderr, "Error opening password file %s: %s\n",
  93                                 file, strerror(errno));
  94                 return False;
  95         }
  96
  97         ret = cli_credentials_parse_password_fd(credentials, fd, obtained);
  98
  99         close(fd);
 100
 101         return ret;
 102 }
 103
 104 /**
 105  * Read a named file, and parse it for username, domain, realm and password
 106  *
 107  * @param credentials Credentials structure on which to set the password
 108  * @param file a named file to read the details from
 109  * @param obtained This enum describes how 'specified' this password is
 110  */
 111
 112 BOOL cli_credentials_parse_file(struct cli_credentials *cred, const char *file, enum credentials_obtained obtained)
 113 {
 114         uint16_t len = 0;
 115         char *ptr, *val, *param;
 116         char **lines;
 117         int i, numlines;
 118
 119         lines = file_lines_load(file, &numlines, NULL);
 120
 121         if (lines == NULL)
 122         {
 123                 /* fail if we can't open the credentials file */
 124                 d_printf("ERROR: Unable to open credentials file!\n");
 125                 return False;
 126         }
 127
 128         for (i = 0; i < numlines; i++) {
 129                 len = strlen(lines[i]);
 130
 131                 if (len == 0)
 132                         continue;
 133
 134                 /* break up the line into parameter & value.
 135                  * will need to eat a little whitespace possibly */
 136                 param = lines[i];
 137                 if (!(ptr = strchr_m (lines[i], '=')))
 138                         continue;
 139
 140                 val = ptr+1;
 141                 *ptr = '\0';
 142
 143                 /* eat leading white space */
 144                 while ((*val!='\0') && ((*val==' ') || (*val=='\t')))
 145                         val++;
 146
 147                 if (strwicmp("password", param) == 0) {
 148                         cli_credentials_set_password(cred, val, obtained);
 149                 } else if (strwicmp("username", param) == 0) {
 150                         cli_credentials_set_username(cred, val, obtained);
 151                 } else if (strwicmp("domain", param) == 0) {
 152                         cli_credentials_set_domain(cred, val, obtained);
 153                 } else if (strwicmp("realm", param) == 0) {
 154                         cli_credentials_set_realm(cred, val, obtained);
 155                 }
 156                 memset(lines[i], 0, len);
 157         }
 158
 159         talloc_free(lines);
 160
 161         return True;
 162 }
 163
 164
 165 /**
 166  * Fill in credentials for the machine trust account, from the secrets database.
 167  *
 168  * @param cred Credentials structure to fill in
 169  * @retval NTSTATUS error detailing any failure
 170  */
 171 NTSTATUS cli_credentials_set_secrets(struct cli_credentials *cred,
 172                                      struct ldb_context *ldb,
 173                                      const char *base,
 174                                      const char *filter)
 175 {
 176         TALLOC_CTX *mem_ctx;
 177
 178         int ldb_ret;
 179         struct ldb_message **msgs;
 180         const char *attrs[] = {
 181                 "secret",
 182                 "priorSecret",
 183                 "samAccountName",
 184                 "flatname",
 185                 "realm",
 186                 "secureChannelType",
 187                 "unicodePwd",
 188                 "msDS-KeyVersionNumber",
 189                 "saltPrincipal",
 190                 "privateKeytab",
 191                 "krb5Keytab",
 192                 NULL
 193         };
 194
 195         const char *machine_account;
 196         const char *password;
 197         const char *old_password;
 198         const char *domain;
 199         const char *realm;
 200         enum netr_SchannelType sct;
 201         const char *salt_principal;
 202         const char *keytab;
 203
 204         /* ok, we are going to get it now, don't recurse back here */
 205         cred->machine_account_pending = False;
 206
 207         /* some other parts of the system will key off this */
 208         cred->machine_account = True;
 209
 210         mem_ctx = talloc_named(cred, 0, "cli_credentials fetch machine password");
 211
 212         if (!ldb) {
 213                 /* Local secrets are stored in secrets.ldb */
 214                 ldb = secrets_db_connect(mem_ctx);
 215                 if (!ldb) {
 216                         /* set anonymous as the fallback, if the machine account won't work */
 217                         cli_credentials_set_anonymous(cred);
 218                         DEBUG(1, ("Could not open secrets.ldb\n"));
 219                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 220                 }
 221         }
 222
 223         /* search for the secret record */
 224         ldb_ret = gendb_search(ldb,
 225                                mem_ctx, ldb_dn_new(mem_ctx, ldb, base),
 226                                &msgs, attrs,
 227                                "%s", filter);
 228         if (ldb_ret == 0) {
 229                 DEBUG(1, ("Could not find entry to match filter: '%s' base: '%s'\n",
 230                           filter, base));
 231                 /* set anonymous as the fallback, if the machine account won't work */
 232                 cli_credentials_set_anonymous(cred);
 233                 talloc_free(mem_ctx);
 234                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 235         } else if (ldb_ret != 1) {
 236                 DEBUG(1, ("Found more than one (%d) entry to match filter: '%s' base: '%s'\n",
 237                           ldb_ret, filter, base));
 238                 /* set anonymous as the fallback, if the machine account won't work */
 239                 cli_credentials_set_anonymous(cred);
 240                 talloc_free(mem_ctx);
 241                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 242         }
 243
 244         password = ldb_msg_find_attr_as_string(msgs[0], "secret", NULL);
 245         old_password = ldb_msg_find_attr_as_string(msgs[0], "priorSecret", NULL);
 246
 247         machine_account = ldb_msg_find_attr_as_string(msgs[0], "samAccountName", NULL);
 248
 249         if (!machine_account) {
 250                 DEBUG(1, ("Could not find 'samAccountName' in join record to domain: %s: filter: '%s' base: '%s'\n",
 251                           cli_credentials_get_domain(cred), filter, base));
 252                 /* set anonymous as the fallback, if the machine account won't work */
 253                 cli_credentials_set_anonymous(cred);
 254                 talloc_free(mem_ctx);
 255                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 256         }
 257
 258         salt_principal = ldb_msg_find_attr_as_string(msgs[0], "saltPrincipal", NULL);
 259         cli_credentials_set_salt_principal(cred, salt_principal);
 260
 261         sct = ldb_msg_find_attr_as_int(msgs[0], "secureChannelType", 0);
 262         if (sct) {
 263                 cli_credentials_set_secure_channel_type(cred, sct);
 264         }
 265
 266         if (!password) {
 267                 const struct ldb_val *nt_password_hash = ldb_msg_find_ldb_val(msgs[0], "unicodePwd");
 268                 struct samr_Password hash;
 269                 ZERO_STRUCT(hash);
 270                 if (nt_password_hash) {
 271                         memcpy(hash.hash, nt_password_hash->data,
 272                                MIN(nt_password_hash->length, sizeof(hash.hash)));
 273
 274                         cli_credentials_set_nt_hash(cred, &hash, CRED_SPECIFIED);
 275                 } else {
 276                         cli_credentials_set_password(cred, NULL, CRED_SPECIFIED);
 277                 }
 278         } else {
 279                 cli_credentials_set_password(cred, password, CRED_SPECIFIED);
 280         }
 281
 282
 283         domain = ldb_msg_find_attr_as_string(msgs[0], "flatname", NULL);
 284         if (domain) {
 285                 cli_credentials_set_domain(cred, domain, CRED_SPECIFIED);
 286         }
 287
 288         realm = ldb_msg_find_attr_as_string(msgs[0], "realm", NULL);
 289         if (realm) {
 290                 cli_credentials_set_realm(cred, realm, CRED_SPECIFIED);
 291         }
 292
 293         cli_credentials_set_username(cred, machine_account, CRED_SPECIFIED);
 294
 295         cli_credentials_set_kvno(cred, ldb_msg_find_attr_as_int(msgs[0], "msDS-KeyVersionNumber", 0));
 296
 297         /* If there was an external keytab specified by reference in
 298          * the LDB, then use this.  Otherwise we will make one up
 299          * (chewing CPU time) from the password */
 300         keytab = ldb_msg_find_attr_as_string(msgs[0], "krb5Keytab", NULL);
 301         if (keytab) {
 302                 cli_credentials_set_keytab_name(cred, keytab, CRED_SPECIFIED);
 303         } else {
 304                 keytab = ldb_msg_find_attr_as_string(msgs[0], "privateKeytab", NULL);
 305                 if (keytab) {
 306                         keytab = talloc_asprintf(mem_ctx, "FILE:%s", private_path(mem_ctx, keytab));
 307                         if (keytab) {
 308                                 cli_credentials_set_keytab_name(cred, keytab, CRED_SPECIFIED);
 309                         }
 310                 }
 311         }
 312         talloc_free(mem_ctx);
 313
 314         return NT_STATUS_OK;
 315 }
 316
 317 /**
 318  * Fill in credentials for the machine trust account, from the secrets database.
 319  *
 320  * @param cred Credentials structure to fill in
 321  * @retval NTSTATUS error detailing any failure
 322  */
 323 NTSTATUS cli_credentials_set_machine_account(struct cli_credentials *cred)
 324 {
 325         char *filter;
 326         /* Bleh, nasty recursion issues: We are setting a machine
 327          * account here, so we don't want the 'pending' flag around
 328          * any more */
 329         cred->machine_account_pending = False;
 330         filter = talloc_asprintf(cred, SECRETS_PRIMARY_DOMAIN_FILTER,
 331                                        cli_credentials_get_domain(cred));
 332         return cli_credentials_set_secrets(cred, NULL, SECRETS_PRIMARY_DOMAIN_DN,
 333                                            filter);
 334 }
 335
 336 /**
 337  * Fill in credentials for the machine trust account, from the secrets database.
 338  *
 339  * @param cred Credentials structure to fill in
 340  * @retval NTSTATUS error detailing any failure
 341  */
 342 NTSTATUS cli_credentials_set_krbtgt(struct cli_credentials *cred)
 343 {
 344         char *filter;
 345         /* Bleh, nasty recursion issues: We are setting a machine
 346          * account here, so we don't want the 'pending' flag around
 347          * any more */
 348         cred->machine_account_pending = False;
 349         filter = talloc_asprintf(cred, SECRETS_KRBTGT_SEARCH,
 350                                        cli_credentials_get_realm(cred),
 351                                        cli_credentials_get_domain(cred));
 352         return cli_credentials_set_secrets(cred, NULL, SECRETS_PRINCIPALS_DN,
 353                                            filter);
 354 }
 355
 356 /**
 357  * Fill in credentials for the machine trust account, from the secrets database.
 358  *
 359  * @param cred Credentials structure to fill in
 360  * @retval NTSTATUS error detailing any failure
 361  */
 362 NTSTATUS cli_credentials_set_stored_principal(struct cli_credentials *cred,
 363                                               const char *serviceprincipal)
 364 {
 365         char *filter;
 366         /* Bleh, nasty recursion issues: We are setting a machine
 367          * account here, so we don't want the 'pending' flag around
 368          * any more */
 369         cred->machine_account_pending = False;
 370         filter = talloc_asprintf(cred, SECRETS_PRINCIPAL_SEARCH,
 371                                  cli_credentials_get_realm(cred),
 372                                  cli_credentials_get_domain(cred),
 373                                  serviceprincipal);
 374         return cli_credentials_set_secrets(cred, NULL, SECRETS_PRINCIPALS_DN,
 375                                            filter);
 376 }
 377
 378 /**
 379  * Ask that when required, the credentials system will be filled with
 380  * machine trust account, from the secrets database.
 381  *
 382  * @param cred Credentials structure to fill in
 383  * @note This function is used to call the above function after, rather
 384  *       than during, popt processing.
 385  *
 386  */
 387 void cli_credentials_set_machine_account_pending(struct cli_credentials *cred)
 388 {
 389         cred->machine_account_pending = True;
 390 }
 391
 392