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         char *q;
  92         int len;
  93
  94         *backend = *domain = NULL;
  95
  96         if ( !config )
  97                 return False;
  98
  99         p = strchr( config, ':' );
 100
 101         /* if no : then the string must be the backend name only */
 102
 103         if ( !p ) {
 104                 *backend = SMB_STRDUP( config );
 105                 return (*backend != NULL);
 106         }
 107
 108         /* split the string and return the two parts */
 109
 110         if ( strlen(p+1) > 0 ) {
 111                 *domain = SMB_STRDUP( p+1 );
 112         }
 113
 114         len = PTR_DIFF(p,config)+1;
 115         if ( (q = SMB_MALLOC_ARRAY( char, len )) == NULL ) {
 116                 SAFE_FREE( *backend );
 117                 return False;
 118         }
 119
 120         StrnCpy( q, config, len-1);
 121         q[len-1] = '\0';
 122         *backend = q;
 123
 124         return True;
 125 }
 126
 127 static NTSTATUS nss_domain_list_add_domain(const char *domain,
 128                                            struct nss_function_entry *nss_backend)
 129 {
 130         struct nss_domain_entry *nss_domain;
 131
 132         nss_domain = TALLOC_ZERO_P(nss_domain_list, struct nss_domain_entry);
 133         if (!nss_domain) {
 134                 DEBUG(0, ("nss_domain_list_add_domain: talloc() failure!\n"));
 135                 return NT_STATUS_NO_MEMORY;
 136         }
 137
 138         nss_domain->backend = nss_backend;
 139         if (domain) {
 140                 nss_domain->domain  = talloc_strdup(nss_domain, domain);
 141                 if (!nss_domain->domain) {
 142                         DEBUG(0, ("nss_domain_list_add_domain: talloc() "
 143                                   "failure!\n"));
 144                         TALLOC_FREE(nss_domain);
 145                         return NT_STATUS_NO_MEMORY;
 146                 }
 147         }
 148
 149         nss_domain->init_status = nss_domain->backend->methods->init(nss_domain);
 150         if (!NT_STATUS_IS_OK(nss_domain->init_status))  {
 151                 DEBUG(0, ("nss_init: Failed to init backend '%s' for domain "
 152                           "'%s'!\n", nss_backend->name, nss_domain->domain));
 153         }
 154
 155         DLIST_ADD(nss_domain_list, nss_domain);
 156
 157         DEBUG(10, ("Added domain '%s' with backend '%s' to nss_domain_list.\n",
 158                    domain, nss_backend->name));
 159
 160         return NT_STATUS_OK;
 161 }
 162
 163 /********************************************************************
 164  Each nss backend must not store global state, but rather be able
 165  to initialize the state on a per domain basis.
 166  *******************************************************************/
 167
 168 static NTSTATUS nss_init(const char **nss_list)
 169 {
 170         NTSTATUS status;
 171         static bool nss_initialized = false;
 172         int i;
 173         char *backend, *domain;
 174         struct nss_function_entry *nss_backend;
 175
 176         /* check for previous successful initializations */
 177
 178         if (nss_initialized) {
 179                 return NT_STATUS_OK;
 180         }
 181
 182         /* The "template" backend should always be registered as it
 183            is a static module */
 184
 185         nss_backend = nss_get_backend("template");
 186         if (nss_backend == NULL) {
 187                 static_init_nss_info;
 188         }
 189
 190         /* Create the list of nss_domains (loading any shared plugins
 191            as necessary) */
 192
 193         for ( i=0; nss_list && nss_list[i]; i++ ) {
 194
 195                 if ( !parse_nss_parm(nss_list[i], &backend, &domain) ) {
 196                         DEBUG(0,("nss_init: failed to parse \"%s\"!\n",
 197                                  nss_list[i]));
 198                         continue;
 199                 }
 200
 201                 DEBUG(10, ("parsed backend = '%s', domain = '%s'\n",
 202                            backend, domain));
 203
 204                 /* validate the backend */
 205
 206                 nss_backend = nss_get_backend(backend);
 207                 if (nss_backend == NULL) {
 208                         /* attempt to register the backend */
 209                         status = smb_probe_module( "nss_info", backend );
 210                         if ( !NT_STATUS_IS_OK(status) ) {
 211                                 continue;
 212                         }
 213                 }
 214
 215                 /* try again */
 216                 nss_backend = nss_get_backend(backend);
 217                 if (nss_backend == NULL) {
 218                         DEBUG(0, ("nss_init: unregistered backend %s!. "
 219                                   "Skipping\n", backend));
 220                         continue;
 221                 }
 222
 223                 /*
 224                  * The first config item of the list without an explicit domain
 225                  * is treated as the default nss info backend.
 226                  */
 227                 if ((domain == NULL) && (default_backend == NULL)) {
 228                         DEBUG(10, ("nss_init: using '%s' as default backend.\n",
 229                                    backend));
 230                         default_backend = nss_backend;
 231                 }
 232
 233                 status = nss_domain_list_add_domain(domain, nss_backend);
 234                 if (!NT_STATUS_IS_OK(status)) {
 235                         return status;
 236                 }
 237
 238                 /* cleanup */
 239
 240                 SAFE_FREE( backend );
 241                 SAFE_FREE( domain );
 242         }
 243
 244         if ( !nss_domain_list ) {
 245                 DEBUG(3,("nss_init: no nss backends configured.  "
 246                          "Defaulting to \"template\".\n"));
 247
 248
 249                 /* we should default to use template here */
 250         }
 251
 252         nss_initialized = true;
 253
 254         return NT_STATUS_OK;
 255 }
 256
 257 /********************************************************************
 258  *******************************************************************/
 259
 260 static struct nss_domain_entry *find_nss_domain( const char *domain )
 261 {
 262         NTSTATUS status;
 263         struct nss_domain_entry *p;
 264
 265         status = nss_init( lp_winbind_nss_info() );
 266         if ( !NT_STATUS_IS_OK(status) ) {
 267                 DEBUG(4,("find_nss_domain: Failed to init nss_info API "
 268                          "(%s)!\n", nt_errstr(status)));
 269                 return NULL;
 270         }
 271
 272         for ( p=nss_domain_list; p; p=p->next ) {
 273                 if ( strequal( p->domain, domain ) )
 274                         break;
 275         }
 276
 277         /* If we didn't find a match, then use the default nss backend */
 278
 279         if ( !p ) {
 280                 if (!default_backend) {
 281                         return NULL;
 282                 }
 283
 284                 status = nss_domain_list_add_domain(domain, default_backend);
 285                 if (!NT_STATUS_IS_OK(status)) {
 286                         return NULL;
 287                 }
 288
 289                 /*
 290                  * HACK ALERT:
 291                  * Here, we use the fact that the new domain was added at
 292                  * the beginning of the list...
 293                  */
 294                 p = nss_domain_list;
 295         }
 296
 297         if ( !NT_STATUS_IS_OK( p->init_status ) ) {
 298                p->init_status = p->backend->methods->init( p );
 299         }
 300
 301         return p;
 302 }
 303
 304 /********************************************************************
 305  *******************************************************************/
 306
 307 NTSTATUS nss_get_info( const char *domain, const struct dom_sid *user_sid,
 308                        TALLOC_CTX *ctx,
 309                        ADS_STRUCT *ads, LDAPMessage *msg,
 310                        const char **homedir, const char **shell,
 311                        const char **gecos, gid_t *p_gid)
 312 {
 313         struct nss_domain_entry *p;
 314         struct nss_info_methods *m;
 315
 316         DEBUG(10, ("nss_get_info called for sid [%s] in domain '%s'\n",
 317                    sid_string_dbg(user_sid), domain?domain:"NULL"));
 318
 319         if ( (p = find_nss_domain( domain )) == NULL ) {
 320                 DEBUG(4,("nss_get_info: Failed to find nss domain pointer for %s\n",
 321                          domain ));
 322                 return NT_STATUS_NOT_FOUND;
 323         }
 324
 325         m = p->backend->methods;
 326
 327         return m->get_nss_info( p, user_sid, ctx, ads, msg,
 328                                 homedir, shell, gecos, p_gid );
 329 }
 330
 331 /********************************************************************
 332  *******************************************************************/
 333
 334  NTSTATUS nss_map_to_alias( TALLOC_CTX *mem_ctx, const char *domain,
 335                             const char *name, char **alias )
 336 {
 337         struct nss_domain_entry *p;
 338         struct nss_info_methods *m;
 339
 340         if ( (p = find_nss_domain( domain )) == NULL ) {
 341                 DEBUG(4,("nss_map_to_alias: Failed to find nss domain pointer for %s\n",
 342                          domain ));
 343                 return NT_STATUS_NOT_FOUND;
 344         }
 345
 346         m = p->backend->methods;
 347
 348         return m->map_to_alias(mem_ctx, p, name, alias);
 349 }
 350
 351
 352 /********************************************************************
 353  *******************************************************************/
 354
 355  NTSTATUS nss_map_from_alias( TALLOC_CTX *mem_ctx, const char *domain,
 356                               const char *alias, char **name )
 357 {
 358         struct nss_domain_entry *p;
 359         struct nss_info_methods *m;
 360
 361         if ( (p = find_nss_domain( domain )) == NULL ) {
 362                 DEBUG(4,("nss_map_from_alias: Failed to find nss domain pointer for %s\n",
 363                          domain ));
 364                 return NT_STATUS_NOT_FOUND;
 365         }
 366
 367         m = p->backend->methods;
 368
 369         return m->map_from_alias( mem_ctx, p, alias, name );
 370 }
 371
 372 /********************************************************************
 373  *******************************************************************/
 374
 375  NTSTATUS nss_close( const char *parameters )
 376 {
 377         struct nss_domain_entry *p = nss_domain_list;
 378         struct nss_domain_entry *q;
 379
 380         while ( p && p->backend && p->backend->methods ) {
 381                 /* close the backend */
 382                 p->backend->methods->close_fn();
 383
 384                 /* free the memory */
 385                 q = p;
 386                 p = p->next;
 387                 TALLOC_FREE( q );
 388         }
 389
 390         return NT_STATUS_OK;
 391 }
 392