source3/auth/auth.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Password and authentication handling
   4    Copyright (C) Andrew Bartlett         2001-2002
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22
  23 #undef DBGC_CLASS
  24 #define DBGC_CLASS DBGC_AUTH
  25
  26 /** List of various built-in authentication modules */
  27
  28 const struct auth_init_function_entry builtin_auth_init_functions[] = {
  29         { "guest", auth_init_guest },
  30         { "rhosts", auth_init_rhosts },
  31         { "hostsequiv", auth_init_hostsequiv },
  32         { "sam", auth_init_sam },
  33         { "samstrict", auth_init_samstrict },
  34         { "unix", auth_init_unix },
  35         { "smbserver", auth_init_smbserver },
  36         { "ntdomain", auth_init_ntdomain },
  37         { "trustdomain", auth_init_trustdomain },
  38         { "winbind", auth_init_winbind },
  39 #ifdef DEVELOPER
  40         { "name_to_ntstatus", auth_init_name_to_ntstatus },
  41         { "fixed_challenge", auth_init_fixed_challenge },
  42 #endif
  43         { "plugin", auth_init_plugin },
  44         { NULL, NULL}
  45 };
  46
  47 /****************************************************************************
  48  Try to get a challenge out of the various authentication modules.
  49  Returns a const char of length 8 bytes.
  50 ****************************************************************************/
  51
  52 static const uint8 *get_ntlm_challenge(struct auth_context *auth_context)
  53 {
  54         DATA_BLOB challenge = data_blob(NULL, 0);
  55         char *challenge_set_by = NULL;
  56         auth_methods *auth_method;
  57         TALLOC_CTX *mem_ctx;
  58
  59         if (auth_context->challenge.length) {
  60                 DEBUG(5, ("get_ntlm_challenge (auth subsystem): returning previous challenge (normal)\n"));
  61                 return auth_context->challenge.data;
  62         }
  63
  64         for (auth_method = auth_context->auth_method_list; auth_method; auth_method = auth_method->next)
  65         {
  66                 if (auth_method->get_chal == NULL) {
  67                         DEBUG(5, ("auth_get_challenge: module %s did not want to specify a challenge\n", auth_method->name));
  68                         continue;
  69                 }
  70
  71                 DEBUG(5, ("auth_get_challenge: getting challenge from module %s\n", auth_method->name));
  72                 if (challenge_set_by != NULL) {
  73                         DEBUG(1, ("auth_get_challenge: CONFIGURATION ERROR: authentication method %s has already specified a challenge.  Challenge by %s ignored.\n",
  74                                   challenge_set_by, auth_method->name));
  75                         continue;
  76                 }
  77
  78                 mem_ctx = talloc_init_named("auth_get_challenge for module %s", auth_method->name);
  79                 if (!mem_ctx) {
  80                         smb_panic("talloc_init_named() failed!");
  81                 }
  82
  83                 challenge = auth_method->get_chal(auth_context, &auth_method->private_data, mem_ctx);
  84                 if (!challenge.length) {
  85                         DEBUG(3, ("auth_get_challenge: getting challenge from authentication method %s FAILED.\n",
  86                                   auth_method->name));
  87                 } else {
  88                         DEBUG(5, ("auth_get_challenge: sucessfully got challenge from module %s\n", auth_method->name));
  89                         auth_context->challenge = challenge;
  90                         challenge_set_by = auth_method->name;
  91                         auth_context->challenge_set_method = auth_method;
  92                 }
  93                 talloc_destroy(mem_ctx);
  94         }
  95
  96         if (!challenge_set_by) {
  97                 uchar chal[8];
  98
  99                 generate_random_buffer(chal, sizeof(chal), False);
 100                 auth_context->challenge = data_blob_talloc(auth_context->mem_ctx,
 101                                                            chal, sizeof(chal));
 102
 103                 challenge_set_by = "random";
 104         }
 105
 106         DEBUG(5, ("auth_context challenge created by %s\n", challenge_set_by));
 107         DEBUG(5, ("challenge is: \n"));
 108         dump_data(5, auth_context->challenge.data, auth_context->challenge.length);
 109
 110         SMB_ASSERT(auth_context->challenge.length == 8);
 111
 112         auth_context->challenge_set_by=challenge_set_by;
 113
 114         return auth_context->challenge.data;
 115 }
 116
 117
 118 /**
 119  * Check user is in correct domain (if required)
 120  *
 121  * @param user Only used to fill in the debug message
 122  *
 123  * @param domain The domain to be verified
 124  *
 125  * @return True if the user can connect with that domain,
 126  *         False otherwise.
 127 **/
 128
 129 static BOOL check_domain_match(const char *user, const char *domain)
 130 {
 131         /*
 132          * If we aren't serving to trusted domains, we must make sure that
 133          * the validation request comes from an account in the same domain
 134          * as the Samba server
 135          */
 136
 137         if (!lp_allow_trusted_domains() &&
 138             !(strequal("", domain) ||
 139               strequal(lp_workgroup(), domain) ||
 140               is_netbios_alias_or_name(domain))) {
 141                 DEBUG(1, ("check_domain_match: Attempt to connect as user %s from domain %s denied.\n", user, domain));
 142                 return False;
 143         } else {
 144                 return True;
 145         }
 146 }
 147
 148 /**
 149  * Check a user's Plaintext, LM or NTLM password.
 150  *
 151  * Check a user's password, as given in the user_info struct and return various
 152  * interesting details in the server_info struct.
 153  *
 154  * This function does NOT need to be in a become_root()/unbecome_root() pair
 155  * as it makes the calls itself when needed.
 156  *
 157  * The return value takes precedence over the contents of the server_info
 158  * struct.  When the return is other than NT_STATUS_OK the contents
 159  * of that structure is undefined.
 160  *
 161  * @param user_info Contains the user supplied components, including the passwords.
 162  *                  Must be created with make_user_info() or one of its wrappers.
 163  *
 164  * @param auth_info Supplies the challenges and some other data.
 165  *                  Must be created with make_auth_info(), and the challenges should be
 166  *                  filled in, either at creation or by calling the challenge geneation
 167  *                  function auth_get_challenge().
 168  *
 169  * @param server_info If successful, contains information about the authentication,
 170  *                    including a SAM_ACCOUNT struct describing the user.
 171  *
 172  * @return An NTSTATUS with NT_STATUS_OK or an appropriate error.
 173  *
 174  **/
 175
 176 static NTSTATUS check_ntlm_password(const struct auth_context *auth_context,
 177                                     const struct auth_usersupplied_info *user_info,
 178                                     struct auth_serversupplied_info **server_info)
 179 {
 180
 181         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 182         const char *pdb_username;
 183         auth_methods *auth_method;
 184         TALLOC_CTX *mem_ctx;
 185
 186         if (!user_info || !auth_context || !server_info) {
 187                 return NT_STATUS_LOGON_FAILURE;
 188         }
 189
 190         DEBUG(3, ("check_password:  Checking password for unmapped user [%s]\\[%s]@[%s] with the new password interface\n",
 191                   user_info->client_domain.str, user_info->smb_name.str, user_info->wksta_name.str));
 192
 193         DEBUG(3, ("check_password:  mapped user is: [%s]\\[%s]@[%s]\n",
 194                   user_info->domain.str, user_info->internal_username.str, user_info->wksta_name.str));
 195         if (auth_context->challenge_set_by) {
 196                 DEBUG(10, ("auth_context challenge created by %s\n", auth_context->challenge_set_by));
 197         }
 198         DEBUG(10, ("challenge is: \n"));
 199         dump_data(5, auth_context->challenge.data, auth_context->challenge.length);
 200
 201 #ifdef DEBUG_PASSWORD
 202         DEBUG(100, ("user_info has passwords of length %d and %d\n",
 203                     user_info->lm_resp.length, user_info->nt_resp.length));
 204         DEBUG(100, ("lm:\n"));
 205         dump_data(100, user_info->lm_resp.data, user_info->lm_resp.length);
 206         DEBUG(100, ("nt:\n"));
 207         dump_data(100, user_info->nt_resp.data, user_info->nt_resp.length);
 208 #endif
 209
 210         /* This needs to be sorted:  If it doesn't match, what should we do? */
 211         if (!check_domain_match(user_info->smb_name.str, user_info->domain.str)) {
 212                 return NT_STATUS_LOGON_FAILURE;
 213         }
 214
 215         for (auth_method = auth_context->auth_method_list;auth_method; auth_method = auth_method->next)
 216         {
 217                 mem_ctx = talloc_init_named("%s authentication for user %s\\%s", auth_method->name,
 218                                             user_info->domain.str, user_info->smb_name.str);
 219
 220                 nt_status = auth_method->auth(auth_context, auth_method->private_data, mem_ctx, user_info, server_info);
 221                 if (NT_STATUS_IS_OK(nt_status)) {
 222                         DEBUG(3, ("check_password: %s authentication for user [%s] suceeded\n",
 223                                   auth_method->name, user_info->smb_name.str));
 224                 } else {
 225                         DEBUG(5, ("check_password: %s authentication for user [%s] FAILED with error %s\n",
 226                                   auth_method->name, user_info->smb_name.str, nt_errstr(nt_status)));
 227                 }
 228
 229                 talloc_destroy(mem_ctx);
 230
 231                 if (NT_STATUS_IS_OK(nt_status)) {
 232                         break;
 233                 }
 234         }
 235
 236         /* This is one of the few places the *relies* (rather than just sets defaults
 237            on the value of lp_security().  This needs to change.  A new paramater
 238            perhaps? */
 239         if (lp_security() >= SEC_SERVER) {
 240                 smb_user_control(user_info, *server_info, nt_status);
 241         }
 242
 243         if (NT_STATUS_IS_OK(nt_status)) {
 244                 pdb_username = pdb_get_username((*server_info)->sam_account);
 245                 if (!(*server_info)->guest) {
 246                         /* We might not be root if we are an RPC call */
 247                         become_root();
 248                         nt_status = smb_pam_accountcheck(pdb_username);
 249                         unbecome_root();
 250
 251                         if (NT_STATUS_IS_OK(nt_status)) {
 252                                 DEBUG(5, ("check_password:  PAM Account for user [%s] suceeded\n",
 253                                           pdb_username));
 254                         } else {
 255                                 DEBUG(3, ("check_password:  PAM Account for user [%s] FAILED with error %s\n",
 256                                           pdb_username, nt_errstr(nt_status)));
 257                         }
 258                 }
 259
 260                 if (NT_STATUS_IS_OK(nt_status)) {
 261                         DEBUG((*server_info)->guest ? 5 : 2,
 262                               ("check_password:  %sauthentication for user [%s] -> [%s] -> [%s] suceeded\n",
 263                                (*server_info)->guest ? "guest " : "",
 264                                user_info->smb_name.str,
 265                                user_info->internal_username.str,
 266                                pdb_username));
 267                 }
 268         }
 269
 270         if (!NT_STATUS_IS_OK(nt_status)) {
 271                 DEBUG(2, ("check_password:  Authentication for user [%s] -> [%s] FAILED with error %s\n",
 272                           user_info->smb_name.str, user_info->internal_username.str,
 273                           nt_errstr(nt_status)));
 274                 ZERO_STRUCTP(server_info);
 275         }
 276         return nt_status;
 277 }
 278
 279 /***************************************************************************
 280  Clear out a auth_context, and destroy the attached TALLOC_CTX
 281 ***************************************************************************/
 282
 283 static void free_auth_context(struct auth_context **auth_context)
 284 {
 285         if (*auth_context != NULL) {
 286                 talloc_destroy((*auth_context)->mem_ctx);
 287         }
 288         *auth_context = NULL;
 289 }
 290
 291 /***************************************************************************
 292  Make a auth_info struct
 293 ***************************************************************************/
 294
 295 static NTSTATUS make_auth_context(struct auth_context **auth_context)
 296 {
 297         TALLOC_CTX *mem_ctx;
 298
 299         mem_ctx = talloc_init_named("authentication context");
 300
 301         *auth_context = talloc(mem_ctx, sizeof(**auth_context));
 302         if (!*auth_context) {
 303                 DEBUG(0,("make_auth_context: talloc failed!\n"));
 304                 talloc_destroy(mem_ctx);
 305                 return NT_STATUS_NO_MEMORY;
 306         }
 307         ZERO_STRUCTP(*auth_context);
 308
 309         (*auth_context)->mem_ctx = mem_ctx;
 310         (*auth_context)->check_ntlm_password = check_ntlm_password;
 311         (*auth_context)->get_ntlm_challenge = get_ntlm_challenge;
 312         (*auth_context)->free = free_auth_context;
 313
 314         return NT_STATUS_OK;
 315 }
 316
 317 /***************************************************************************
 318  Make a auth_info struct for the auth subsystem
 319 ***************************************************************************/
 320
 321 static NTSTATUS make_auth_context_text_list(struct auth_context **auth_context, char **text_list)
 322 {
 323         auth_methods *list = NULL;
 324         auth_methods *t = NULL;
 325         auth_methods *tmp;
 326         int i;
 327         NTSTATUS nt_status;
 328
 329         if (!text_list) {
 330                 DEBUG(2,("No auth method list!?\n"));
 331                 return NT_STATUS_UNSUCCESSFUL;
 332         }
 333
 334         if (!NT_STATUS_IS_OK(nt_status = make_auth_context(auth_context))) {
 335                 return nt_status;
 336         }
 337
 338         for (;*text_list; text_list++)
 339         {
 340                 DEBUG(5,("Attempting to find an auth method to match %s\n", *text_list));
 341                 for (i = 0; builtin_auth_init_functions[i].name; i++)
 342                 {
 343                         if (strequal(builtin_auth_init_functions[i].name, *text_list))
 344                         {
 345
 346                                 char *module_name = smb_xstrdup(*text_list);
 347                                 char *module_params = NULL;
 348                                 char *p;
 349
 350                                 p = strchr(module_name, ':');
 351
 352                                 if (p) {
 353                                         *p = 0;
 354
 355                                         module_params = p+1;
 356
 357                                         trim_string(module_params, " ", " ");
 358                                 }
 359
 360                                 trim_string(module_name, " ", " ");
 361
 362                                 DEBUG(5,("Found auth method %s (at pos %d)\n", *text_list, i));
 363                                 if (NT_STATUS_IS_OK(builtin_auth_init_functions[i].init(*auth_context, module_params, &t))) {
 364                                         DEBUG(5,("auth method %s has a valid init\n", *text_list));
 365                                         DLIST_ADD_END(list, t, tmp);
 366                                 } else {
 367                                         DEBUG(0,("auth method %s did not correctly init\n", *text_list));
 368                                 }
 369                                 SAFE_FREE(module_name);
 370                                 break;
 371                         }
 372                 }
 373         }
 374
 375         (*auth_context)->auth_method_list = list;
 376
 377         return nt_status;
 378 }
 379
 380 /***************************************************************************
 381  Make a auth_context struct for the auth subsystem
 382 ***************************************************************************/
 383
 384 NTSTATUS make_auth_context_subsystem(struct auth_context **auth_context)
 385 {
 386         char **auth_method_list = NULL;
 387         NTSTATUS nt_status;
 388
 389         if (lp_auth_methods() && !str_list_copy(&auth_method_list, lp_auth_methods())) {
 390                 return NT_STATUS_NO_MEMORY;
 391         }
 392
 393         if (auth_method_list == NULL) {
 394                 switch (lp_security())
 395                 {
 396                 case SEC_DOMAIN:
 397                         DEBUG(5,("Making default auth method list for security=domain\n"));
 398                         auth_method_list = str_list_make("guest sam ntdomain");
 399                         break;
 400                 case SEC_SERVER:
 401                         DEBUG(5,("Making default auth method list for security=server\n"));
 402                         auth_method_list = str_list_make("guest sam smbserver");
 403                         break;
 404                 case SEC_USER:
 405                         if (lp_encrypted_passwords()) {
 406                                 DEBUG(5,("Making default auth method list for security=user, encrypt passwords = yes\n"));
 407                                 auth_method_list = str_list_make("guest sam");
 408                         } else {
 409                                 DEBUG(5,("Making default auth method list for security=user, encrypt passwords = no\n"));
 410                                 auth_method_list = str_list_make("guest unix");
 411                         }
 412                         break;
 413                 case SEC_SHARE:
 414                         if (lp_encrypted_passwords()) {
 415                                 DEBUG(5,("Making default auth method list for security=share, encrypt passwords = yes\n"));
 416                                 auth_method_list = str_list_make("guest sam");
 417                         } else {
 418                                 DEBUG(5,("Making default auth method list for security=share, encrypt passwords = no\n"));
 419                                 auth_method_list = str_list_make("guest unix");
 420                         }
 421                         break;
 422                 case SEC_ADS:
 423                         DEBUG(5,("Making default auth method list for security=ADS\n"));
 424                         auth_method_list = str_list_make("guest sam ads ntdomain");
 425                         break;
 426                 default:
 427                         DEBUG(5,("Unknown auth method!\n"));
 428                         return NT_STATUS_UNSUCCESSFUL;
 429                 }
 430         } else {
 431                 DEBUG(5,("Using specified auth order\n"));
 432         }
 433
 434         if (!NT_STATUS_IS_OK(nt_status = make_auth_context_text_list(auth_context, auth_method_list))) {
 435                 str_list_free(&auth_method_list);
 436                 return nt_status;
 437         }
 438
 439         str_list_free(&auth_method_list);
 440         return nt_status;
 441 }
 442
 443 /***************************************************************************
 444  Make a auth_info struct with a fixed challenge
 445 ***************************************************************************/
 446
 447 NTSTATUS make_auth_context_fixed(struct auth_context **auth_context, uchar chal[8])
 448 {
 449         NTSTATUS nt_status;
 450         if (!NT_STATUS_IS_OK(nt_status = make_auth_context_subsystem(auth_context))) {
 451                 return nt_status;
 452         }
 453
 454         (*auth_context)->challenge = data_blob(chal, 8);
 455         return nt_status;
 456 }
 457
 458