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