source3/winbindd/nss_info.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Idmap NSS headers
   4
   5    Copyright (C) Gerald Carter             2006
   6    Copyright (C) Michael Adam 2008
   7
   8    This library is free software; you can redistribute it and/or
   9    modify it under the terms of the GNU Lesser General Public
  10    License as published by the Free Software Foundation; either
  11    version 3 of the License, or (at your option) any later version.
  12
  13    This library is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16    Library General Public License for more details.
  17
  18    You should have received a copy of the GNU Lesser General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "ads.h"
  24 #include "nss_info.h"
  25
  26 static struct nss_function_entry *backends = NULL;
  27 static struct nss_function_entry *default_backend = NULL;
  28 static struct nss_domain_entry *nss_domain_list = NULL;
  29
  30 /**********************************************************************
  31  Get idmap nss methods.
  32 **********************************************************************/
  33
  34 static struct nss_function_entry *nss_get_backend(const char *name )
  35 {
  36         struct nss_function_entry *entry = backends;
  37
  38         for(entry = backends; entry; entry = entry->next) {
  39                 if ( strequal(entry->name, name) )
  40                         return entry;
  41         }
  42
  43         return NULL;
  44 }
  45
  46 /*********************************************************************
  47  Allow a module to register itself as a backend.
  48 **********************************************************************/
  49
  50  NTSTATUS smb_register_idmap_nss(int version, const char *name, struct nss_info_methods *methods)
  51 {
  52         struct nss_function_entry *entry;
  53
  54         if ((version != SMB_NSS_INFO_INTERFACE_VERSION)) {
  55                 DEBUG(0, ("smb_register_idmap_nss: Failed to register idmap_nss module.\n"
  56                           "The module was compiled against SMB_NSS_INFO_INTERFACE_VERSION %d,\n"
  57                           "current SMB_NSS_INFO_INTERFACE_VERSION is %d.\n"
  58                           "Please recompile against the current version of samba!\n",
  59                           version, SMB_NSS_INFO_INTERFACE_VERSION));
  60                 return NT_STATUS_OBJECT_TYPE_MISMATCH;
  61         }
  62
  63         if (!name || !name[0] || !methods) {
  64                 DEBUG(0,("smb_register_idmap_nss: called with NULL pointer or empty name!\n"));
  65                 return NT_STATUS_INVALID_PARAMETER;
  66         }
  67
  68         if ( nss_get_backend(name) ) {
  69                 DEBUG(0,("smb_register_idmap_nss: idmap module %s "
  70                          "already registered!\n", name));
  71                 return NT_STATUS_OBJECT_NAME_COLLISION;
  72         }
  73
  74         entry = SMB_XMALLOC_P(struct nss_function_entry);
  75         entry->name = smb_xstrdup(name);
  76         entry->methods = methods;
  77
  78         DLIST_ADD(backends, entry);
  79         DEBUG(5, ("smb_register_idmap_nss: Successfully added idmap "
  80                   "nss backend '%s'\n", name));
  81
  82         return NT_STATUS_OK;
  83 }
  84
  85 /********************************************************************
  86  *******************************************************************/
  87
  88 static bool parse_nss_parm( const char *config, char **backend, char **domain )
  89 {
  90         char *p;
  91
  92         *backend = *domain = NULL;
  93
  94         if ( !config )
  95                 return False;
  96
  97         p = strchr( config, ':' );
  98
  99         /* if no : then the string must be the backend name only */
 100
 101         if ( !p ) {
 102                 *backend = SMB_STRDUP( config );
 103                 return (*backend != NULL);
 104         }
 105
 106         /* split the string and return the two parts */
 107
 108         if ( strlen(p+1) > 0 ) {
 109                 *domain = SMB_STRDUP( p+1 );
 110         }
 111
 112         *backend = SMB_STRNDUP(config, PTR_DIFF(p, config));
 113         return (*backend != NULL);
 114 }
 115
 116 static NTSTATUS nss_domain_list_add_domain(const char *domain,
 117                                            struct nss_function_entry *nss_backend)
 118 {
 119         struct nss_domain_entry *nss_domain;
 120
 121         nss_domain = talloc_zero(nss_domain_list, struct nss_domain_entry);
 122         if (!nss_domain) {
 123                 DEBUG(0, ("nss_domain_list_add_domain: talloc() failure!\n"));
 124                 return NT_STATUS_NO_MEMORY;
 125         }
 126
 127         nss_domain->backend = nss_backend;
 128         if (domain) {
 129                 nss_domain->domain  = talloc_strdup(nss_domain, domain);
 130                 if (!nss_domain->domain) {
 131                         DEBUG(0, ("nss_domain_list_add_domain: talloc() "
 132                                   "failure!\n"));
 133                         TALLOC_FREE(nss_domain);
 134                         return NT_STATUS_NO_MEMORY;
 135                 }
 136         }
 137
 138         nss_domain->init_status = nss_domain->backend->methods->init(nss_domain);
 139         if (!NT_STATUS_IS_OK(nss_domain->init_status))  {
 140                 DEBUG(0, ("nss_init: Failed to init backend '%s' for domain "
 141                           "'%s'!\n", nss_backend->name, nss_domain->domain));
 142         }
 143
 144         DLIST_ADD(nss_domain_list, nss_domain);
 145
 146         DEBUG(10, ("Added domain '%s' with backend '%s' to nss_domain_list.\n",
 147                    domain, nss_backend->name));
 148
 149         return NT_STATUS_OK;
 150 }
 151
 152 /********************************************************************
 153  Each nss backend must not store global state, but rather be able
 154  to initialize the state on a per domain basis.
 155  *******************************************************************/
 156
 157 static NTSTATUS nss_init(const char **nss_list)
 158 {
 159         NTSTATUS status;
 160         static bool nss_initialized = false;
 161         int i;
 162         char *backend, *domain;
 163         struct nss_function_entry *nss_backend;
 164
 165         /* check for previous successful initializations */
 166
 167         if (nss_initialized) {
 168                 return NT_STATUS_OK;
 169         }
 170
 171         /* The "template" backend should always be registered as it
 172            is a static module */
 173
 174         nss_backend = nss_get_backend("template");
 175         if (nss_backend == NULL) {
 176                 static_init_nss_info;
 177         }
 178
 179         /* Create the list of nss_domains (loading any shared plugins
 180            as necessary) */
 181
 182         for ( i=0; nss_list && nss_list[i]; i++ ) {
 183
 184                 if ( !parse_nss_parm(nss_list[i], &backend, &domain) ) {
 185                         DEBUG(0,("nss_init: failed to parse \"%s\"!\n",
 186                                  nss_list[i]));
 187                         continue;
 188                 }
 189
 190                 DEBUG(10, ("parsed backend = '%s', domain = '%s'\n",
 191                            backend, domain));
 192
 193                 /* validate the backend */
 194
 195                 nss_backend = nss_get_backend(backend);
 196                 if (nss_backend == NULL) {
 197                         /*
 198                          * This is a freaking hack. We don't have proper
 199                          * modules for nss_info backends. Right now we have
 200                          * our standard nss_info backends in the ad backend.
 201                          */
 202                         status = smb_probe_module("idmap", "ad");
 203                         if ( !NT_STATUS_IS_OK(status) ) {
 204                                 continue;
 205                         }
 206                 }
 207
 208                 nss_backend = nss_get_backend(backend);
 209                 if (nss_backend == NULL) {
 210                         /* attempt to register the backend */
 211                         status = smb_probe_module( "nss_info", backend );
 212                         if ( !NT_STATUS_IS_OK(status) ) {
 213                                 continue;
 214                         }
 215                 }
 216
 217                 /* try again */
 218                 nss_backend = nss_get_backend(backend);
 219                 if (nss_backend == NULL) {
 220                         DEBUG(0, ("nss_init: unregistered backend %s!. "
 221                                   "Skipping\n", backend));
 222                         continue;
 223                 }
 224
 225                 /*
 226                  * The first config item of the list without an explicit domain
 227                  * is treated as the default nss info backend.
 228                  */
 229                 if ((domain == NULL) && (default_backend == NULL)) {
 230                         DEBUG(10, ("nss_init: using '%s' as default backend.\n",
 231                                    backend));
 232                         default_backend = nss_backend;
 233                 }
 234
 235                 status = nss_domain_list_add_domain(domain, nss_backend);
 236                 if (!NT_STATUS_IS_OK(status)) {
 237                         return status;
 238                 }
 239
 240                 /* cleanup */
 241
 242                 SAFE_FREE( backend );
 243                 SAFE_FREE( domain );
 244         }
 245
 246         if ( !nss_domain_list ) {
 247                 DEBUG(3,("nss_init: no nss backends configured.  "
 248                          "Defaulting to \"template\".\n"));
 249
 250
 251                 /* we should default to use template here */
 252         }
 253
 254         nss_initialized = true;
 255
 256         return NT_STATUS_OK;
 257 }
 258
 259 /********************************************************************
 260  *******************************************************************/
 261
 262 static struct nss_domain_entry *find_nss_domain( const char *domain )
 263 {
 264         NTSTATUS status;
 265         struct nss_domain_entry *p;
 266
 267         status = nss_init( lp_winbind_nss_info() );
 268         if ( !NT_STATUS_IS_OK(status) ) {
 269                 DEBUG(4,("find_nss_domain: Failed to init nss_info API "
 270                          "(%s)!\n", nt_errstr(status)));
 271                 return NULL;
 272         }
 273
 274         for ( p=nss_domain_list; p; p=p->next ) {
 275                 if ( strequal( p->domain, domain ) )
 276                         break;
 277         }
 278
 279         /* If we didn't find a match, then use the default nss backend */
 280
 281         if ( !p ) {
 282                 if (!default_backend) {
 283                         return NULL;
 284                 }
 285
 286                 status = nss_domain_list_add_domain(domain, default_backend);
 287                 if (!NT_STATUS_IS_OK(status)) {
 288                         return NULL;
 289                 }
 290
 291                 /*
 292                  * HACK ALERT:
 293                  * Here, we use the fact that the new domain was added at
 294                  * the beginning of the list...
 295                  */
 296                 p = nss_domain_list;
 297         }
 298
 299         if ( !NT_STATUS_IS_OK( p->init_status ) ) {
 300                p->init_status = p->backend->methods->init( p );
 301         }
 302
 303         return p;
 304 }
 305
 306 /********************************************************************
 307  *******************************************************************/
 308
 309 NTSTATUS nss_get_info( const char *domain, const struct dom_sid *user_sid,
 310                        TALLOC_CTX *ctx,
 311                        const char **homedir, const char **shell,
 312                        const char **gecos, gid_t *p_gid)
 313 {
 314         struct nss_domain_entry *p;
 315         struct nss_info_methods *m;
 316
 317         DEBUG(10, ("nss_get_info called for sid [%s] in domain '%s'\n",
 318                    sid_string_dbg(user_sid), domain?domain:"NULL"));
 319
 320         if ( (p = find_nss_domain( domain )) == NULL ) {
 321                 DEBUG(4,("nss_get_info: Failed to find nss domain pointer for %s\n",
 322                          domain ));
 323                 return NT_STATUS_NOT_FOUND;
 324         }
 325
 326         m = p->backend->methods;
 327
 328         return m->get_nss_info( p, user_sid, ctx,
 329                                 homedir, shell, gecos, p_gid );
 330 }
 331
 332 /********************************************************************
 333  *******************************************************************/
 334
 335  NTSTATUS nss_map_to_alias( TALLOC_CTX *mem_ctx, const char *domain,
 336                             const char *name, char **alias )
 337 {
 338         struct nss_domain_entry *p;
 339         struct nss_info_methods *m;
 340
 341         if ( (p = find_nss_domain( domain )) == NULL ) {
 342                 DEBUG(4,("nss_map_to_alias: Failed to find nss domain pointer for %s\n",
 343                          domain ));
 344                 return NT_STATUS_NOT_FOUND;
 345         }
 346
 347         m = p->backend->methods;
 348
 349         return m->map_to_alias(mem_ctx, p, name, alias);
 350 }
 351
 352
 353 /********************************************************************
 354  *******************************************************************/
 355
 356  NTSTATUS nss_map_from_alias( TALLOC_CTX *mem_ctx, const char *domain,
 357                               const char *alias, char **name )
 358 {
 359         struct nss_domain_entry *p;
 360         struct nss_info_methods *m;
 361
 362         if ( (p = find_nss_domain( domain )) == NULL ) {
 363                 DEBUG(4,("nss_map_from_alias: Failed to find nss domain pointer for %s\n",
 364                          domain ));
 365                 return NT_STATUS_NOT_FOUND;
 366         }
 367
 368         m = p->backend->methods;
 369
 370         return m->map_from_alias( mem_ctx, p, alias, name );
 371 }
 372
 373 /********************************************************************
 374  *******************************************************************/
 375
 376  NTSTATUS nss_close( const char *parameters )
 377 {
 378         struct nss_domain_entry *p = nss_domain_list;
 379         struct nss_domain_entry *q;
 380
 381         while ( p && p->backend && p->backend->methods ) {
 382                 /* close the backend */
 383                 p->backend->methods->close_fn();
 384
 385                 /* free the memory */
 386                 q = p;
 387                 p = p->next;
 388                 TALLOC_FREE( q );
 389         }
 390
 391         return NT_STATUS_OK;
 392 }
 393