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