source/winbindd/nss_info.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Idmap NSS headers
   4
   5    Copyright (C) Gerald Carter             2006
   6
   7    This library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 3 of the License, or (at your option) any later version.
  11
  12    This library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "nss_info.h"
  23
  24 static struct nss_function_entry *backends = NULL;
  25 static struct nss_domain_entry *nss_domain_list = NULL;
  26
  27 /**********************************************************************
  28  Get idmap nss methods.
  29 **********************************************************************/
  30
  31 static struct nss_function_entry *nss_get_backend(const char *name )
  32 {
  33         struct nss_function_entry *entry = backends;
  34
  35         for(entry = backends; entry; entry = entry->next) {
  36                 if ( strequal(entry->name, name) )
  37                         return entry;
  38         }
  39
  40         return NULL;
  41 }
  42
  43 /*********************************************************************
  44  Allow a module to register itself as a backend.
  45 **********************************************************************/
  46
  47  NTSTATUS smb_register_idmap_nss(int version, const char *name, struct nss_info_methods *methods)
  48 {
  49         struct nss_function_entry *entry;
  50
  51         if ((version != SMB_NSS_INFO_INTERFACE_VERSION)) {
  52                 DEBUG(0, ("smb_register_idmap_nss: Failed to register idmap_nss module.\n"
  53                           "The module was compiled against SMB_NSS_INFO_INTERFACE_VERSION %d,\n"
  54                           "current SMB_NSS_INFO_INTERFACE_VERSION is %d.\n"
  55                           "Please recompile against the current version of samba!\n",
  56                           version, SMB_NSS_INFO_INTERFACE_VERSION));
  57                 return NT_STATUS_OBJECT_TYPE_MISMATCH;
  58         }
  59
  60         if (!name || !name[0] || !methods) {
  61                 DEBUG(0,("smb_register_idmap_nss: called with NULL pointer or empty name!\n"));
  62                 return NT_STATUS_INVALID_PARAMETER;
  63         }
  64
  65         if ( nss_get_backend(name) ) {
  66                 DEBUG(0,("smb_register_idmap_nss: idmap module %s "
  67                          "already registered!\n", name));
  68                 return NT_STATUS_OBJECT_NAME_COLLISION;
  69         }
  70
  71         entry = SMB_XMALLOC_P(struct nss_function_entry);
  72         entry->name = smb_xstrdup(name);
  73         entry->methods = methods;
  74
  75         DLIST_ADD(backends, entry);
  76         DEBUG(5, ("smb_register_idmap_nss: Successfully added idmap "
  77                   "nss backend '%s'\n", name));
  78
  79         return NT_STATUS_OK;
  80 }
  81
  82 /********************************************************************
  83  *******************************************************************/
  84
  85 static bool parse_nss_parm( const char *config, char **backend, char **domain )
  86 {
  87         char *p;
  88         char *q;
  89         int len;
  90
  91         *backend = *domain = NULL;
  92
  93         if ( !config )
  94                 return False;
  95
  96         p = strchr( config, ':' );
  97
  98         /* if no : then the string must be the backend name only */
  99
 100         if ( !p ) {
 101                 *backend = SMB_STRDUP( config );
 102                 return (*backend != NULL);
 103         }
 104
 105         /* split the string and return the two parts */
 106
 107         if ( strlen(p+1) > 0 ) {
 108                 *domain = SMB_STRDUP( p+1 );
 109         }
 110
 111         len = PTR_DIFF(p,config)+1;
 112         if ( (q = SMB_MALLOC_ARRAY( char, len )) == NULL ) {
 113                 SAFE_FREE( *backend );
 114                 return False;
 115         }
 116
 117         StrnCpy( q, config, len-1);
 118         q[len-1] = '\0';
 119         *backend = q;
 120
 121         return True;
 122 }
 123
 124 /********************************************************************
 125  Each nss backend must not store global state, but rather be able
 126  to initialize the state on a per domain basis.
 127  *******************************************************************/
 128
 129  NTSTATUS nss_init( const char **nss_list )
 130 {
 131         NTSTATUS status;
 132         static NTSTATUS nss_initialized = NT_STATUS_UNSUCCESSFUL;
 133         int i;
 134         char *backend, *domain;
 135         struct nss_function_entry *nss_backend;
 136         struct nss_domain_entry *nss_domain;
 137
 138         /* check for previous successful initializations */
 139
 140         if ( NT_STATUS_IS_OK(nss_initialized) )
 141                 return NT_STATUS_OK;
 142
 143         /* The "template" backend should alqays be registered as it
 144            is a static module */
 145
 146         if ( (nss_backend = nss_get_backend( "template" )) == NULL ) {
 147                 static_init_nss_info;
 148         }
 149
 150         /* Create the list of nss_domains (loading any shared plugins
 151            as necessary) */
 152
 153         for ( i=0; nss_list && nss_list[i]; i++ ) {
 154
 155                 if ( !parse_nss_parm(nss_list[i], &backend, &domain) )  {
 156                         DEBUG(0,("nss_init: failed to parse \"%s\"!\n",
 157                                  nss_list[i]));
 158                         continue;
 159                 }
 160
 161                 /* validate the backend */
 162
 163                 if ( (nss_backend = nss_get_backend( backend )) == NULL ) {
 164                         /* attempt to register the backend */
 165                         status = smb_probe_module( "nss_info", backend );
 166                         if ( !NT_STATUS_IS_OK(status) ) {
 167                                 continue;
 168                         }
 169
 170                         /* try again */
 171                         if ( (nss_backend = nss_get_backend( backend )) == NULL ) {
 172                                 DEBUG(0,("nss_init: unregistered backend %s!.  Skipping\n",
 173                                          backend));
 174                                 continue;
 175                         }
 176
 177                 }
 178
 179                 /* fill in the nss_domain_entry and add it to the
 180                    list of domains */
 181
 182                 nss_domain = TALLOC_ZERO_P( nss_domain_list, struct nss_domain_entry );
 183                 if ( !nss_domain ) {
 184                         DEBUG(0,("nss_init: talloc() failure!\n"));
 185                         return NT_STATUS_NO_MEMORY;
 186                 }
 187
 188                 nss_domain->backend = nss_backend;
 189                 nss_domain->domain  = talloc_strdup( nss_domain, domain );
 190
 191                 /* Try to init and ave the result */
 192
 193                 nss_domain->init_status = nss_domain->backend->methods->init( nss_domain );
 194                         DLIST_ADD( nss_domain_list, nss_domain );
 195                 if ( !NT_STATUS_IS_OK(nss_domain->init_status) ) {
 196                         DEBUG(0,("nss_init: Failed to init backend for %s domain!\n",
 197                                  nss_domain->domain));
 198                 }
 199
 200                 /* cleanup */
 201
 202                 SAFE_FREE( backend );
 203                 SAFE_FREE( domain );
 204         }
 205
 206         if ( !nss_domain_list ) {
 207                 DEBUG(3,("nss_init: no nss backends configured.  "
 208                          "Defaulting to \"template\".\n"));
 209
 210
 211                 /* we shouild default to use template here */
 212         }
 213
 214
 215         nss_initialized = NT_STATUS_OK;
 216
 217         return NT_STATUS_OK;
 218 }
 219
 220 /********************************************************************
 221  *******************************************************************/
 222
 223 static struct nss_domain_entry *find_nss_domain( const char *domain )
 224 {
 225         NTSTATUS status;
 226         struct nss_domain_entry *p;
 227
 228         status = nss_init( lp_winbind_nss_info() );
 229         if ( !NT_STATUS_IS_OK(status) ) {
 230                 DEBUG(4,("nss_get_info: Failed to init nss_info API (%s)!\n",
 231                          nt_errstr(status)));
 232                 return NULL;
 233         }
 234
 235         for ( p=nss_domain_list; p; p=p->next ) {
 236                 if ( strequal( p->domain, domain ) )
 237                         break;
 238         }
 239
 240         /* If we didn't find a match, then use the default nss info */
 241
 242         if ( !p ) {
 243                 if ( !nss_domain_list ) {
 244                         return NULL;
 245                 }
 246
 247                 p = nss_domain_list;
 248         }
 249
 250         if ( !NT_STATUS_IS_OK( p->init_status ) ) {
 251                p->init_status = p->backend->methods->init( p );
 252         }
 253
 254         return p;
 255 }
 256
 257 /********************************************************************
 258  *******************************************************************/
 259
 260  NTSTATUS nss_get_info( const char *domain, const DOM_SID *user_sid,
 261                        TALLOC_CTX *ctx,
 262                        ADS_STRUCT *ads, LDAPMessage *msg,
 263                        char **homedir, char **shell, char **gecos,
 264                        gid_t *p_gid)
 265 {
 266         struct nss_domain_entry *p;
 267         struct nss_info_methods *m;
 268
 269         if ( (p = find_nss_domain( domain )) == NULL ) {
 270                 DEBUG(4,("nss_get_info: Failed to find nss domain pointer for %s\n",
 271                          domain ));
 272                 return NT_STATUS_NOT_FOUND;
 273         }
 274
 275         m = p->backend->methods;
 276
 277         return m->get_nss_info( p, user_sid, ctx, ads, msg,
 278                                 homedir, shell, gecos, p_gid );
 279 }
 280
 281 /********************************************************************
 282  *******************************************************************/
 283
 284  NTSTATUS nss_close( const char *parameters )
 285 {
 286         struct nss_domain_entry *p = nss_domain_list;
 287         struct nss_domain_entry *q;
 288
 289         while ( p && p->backend && p->backend->methods ) {
 290                 /* close the backend */
 291                 p->backend->methods->close_fn();
 292
 293                 /* free the memory */
 294                 q = p;
 295                 p = p->next;
 296                 TALLOC_FREE( q );
 297         }
 298
 299         return NT_STATUS_OK;
 300 }
 301