workspace/kdm/backend/krb5auth.c

   1 /*
   2
   3 Copyright 1994, 1998  The Open Group
   4 Copyright 2003 Oswald Buddenhagen <ossi@kde.org>
   5
   6 Permission to use, copy, modify, distribute, and sell this software and its
   7 documentation for any purpose is hereby granted without fee, provided that
   8 the above copyright notice appear in all copies and that both that
   9 copyright notice and this permission notice appear in supporting
  10 documentation.
  11
  12 The above copyright notice and this permission notice shall be included
  13 in all copies or substantial portions of the Software.
  14
  15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  16 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  18 IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  19 OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  20 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  21 OTHER DEALINGS IN THE SOFTWARE.
  22
  23 Except as contained in this notice, the name of a copyright holder shall
  24 not be used in advertising or otherwise to promote the sale, use or
  25 other dealings in this Software without prior written authorization
  26 from the copyright holder.
  27
  28 */
  29
  30 /*
  31  * xdm - display manager daemon
  32  * Author: Stephen Gildea, The Open Group
  33  *
  34  * generate Kerberos Version 5 authorization records
  35  */
  36
  37 #include "dm.h"
  38 #include "dm_auth.h"
  39 #include "dm_error.h"
  40
  41 #include <sys/types.h>
  42 #include <sys/stat.h>
  43
  44 #include <krb5/krb5.h>
  45
  46 static krb5_context ctx;
  47
  48 /*ARGSUSED*/
  49 void
  50 krb5InitAuth( unsigned short name_len ATTR_UNUSED, const char *name ATTR_UNUSED )
  51 {
  52         if (krb5_init_context( &ctx ))
  53                 logError( "Error while initializing Krb5 context\n" );
  54 }
  55
  56 /*
  57  * Returns malloc'ed string that is the credentials cache name.
  58  * name should be freed by caller.
  59  */
  60 static char *
  61 krb5CCacheName( const char *dname )
  62 {
  63         char *name;
  64         const char *tmpdir;
  65         int dnl, nl;
  66
  67         tmpdir = getenv( "TMPDIR" );
  68         if (!tmpdir)
  69                 tmpdir = "/tmp";
  70         dnl = strlen( dname );
  71         name = Malloc( strlen( tmpdir ) + dnl + 20 );
  72         if (!name)
  73                 return NULL;
  74         nl = sprintf( name, "FILE:%s/K5C", tmpdir );
  75         cleanUpFileName( dname, name + nl, dnl + 1 );
  76         return name;
  77 }
  78
  79 Xauth *
  80 krb5GetAuthFor( unsigned short namelen, const char *name, const char *dname )
  81 {
  82         Xauth *new;
  83         char *filename;
  84
  85         if (!(new = (Xauth *)Malloc( sizeof(*new) )))
  86                 return (Xauth *)0;
  87         new->family = FamilyWild;
  88         new->address_length = 0;
  89         new->address = 0;
  90         new->number_length = 0;
  91         new->number = 0;
  92
  93         if (dname) {
  94                 if (!(filename = krb5CCacheName( dname ))) {
  95                         free( (char *)new );
  96                         return (Xauth *)0;
  97                 }
  98                 new->data = 0;
  99                 if (!strApp( &new->data, "UU:", filename, (char *)0 )) {
 100                         free( filename );
 101                         free( (char *)new );
 102                         return (Xauth *)0;
 103                 }
 104                 free( filename );
 105                 new->data_length = strlen( new->data );
 106         } else {
 107                 new->data = NULL;
 108                 new->data_length = 0;
 109         }
 110
 111         if (!(new->name = (char *)Malloc( namelen ))) {
 112                 free( (char *)new->data );
 113                 free( (char *)new );
 114                 return (Xauth *)0;
 115         }
 116         memmove( new->name, name, namelen );
 117         new->name_length = namelen;
 118         return new;
 119 }
 120
 121
 122 Xauth *
 123 krb5GetAuth( unsigned short namelen, const char *name )
 124 {
 125         return krb5GetAuthFor( namelen, name, NULL );
 126 }
 127
 128
 129 static krb5_error_code
 130 krb5DisplayCCache( const char *dname, krb5_ccache *ccache_return, char **name )
 131 {
 132         char *ccname;
 133         krb5_error_code code;
 134
 135         if (!(ccname = krb5CCacheName( dname )))
 136                 return ENOMEM;
 137         debug( "resolving Kerberos cache %s\n", ccname );
 138         if ((code = krb5_cc_resolve( ctx, ccname, ccache_return )) || !name)
 139                 free( ccname );
 140         else
 141                 *name = ccname;
 142         return code;
 143 }
 144
 145 char *
 146 krb5Init( const char *user, const char *passwd, const char *dname )
 147 {
 148         krb5_error_code code;
 149         krb5_get_init_creds_opt options;
 150         krb5_principal me;
 151         krb5_creds my_creds;
 152         krb5_ccache ccache;
 153         char *ccname;
 154
 155         if (!ctx)
 156                 return 0;
 157
 158         if ((code = krb5_parse_name( ctx, user, &me ))) {
 159                 logError( "%s while parsing Krb5 user %\"s\n",
 160                           error_message( code ), user );
 161                 return 0;
 162         }
 163
 164         krb5_get_init_creds_opt_init( &options );
 165         /*krb5_get_init_creds_opt_set_tkt_life (&options, 60*60*8);*/ /* 8 hours */
 166
 167         if ((code = krb5_get_init_creds_password( ctx, &my_creds,
 168                                                   me, /* principal */
 169                                                   (char * /* for MIT */) passwd,
 170                                                   0, /* prompter */
 171                                                   0, /* prompter ctx */
 172                                                   0, /* start time delta */
 173                                                   0, /* service */
 174                                                   &options )))
 175         {
 176                 char *my_name = NULL;
 177                 int code2 = krb5_unparse_name( ctx, me, &my_name );
 178                 if (code == KRB5KRB_AP_ERR_BAD_INTEGRITY)
 179                         logError( "Password incorrect for Krb5 principal %\"s\n",
 180                                   code2 ? user : my_name );
 181                 else
 182                         logError( "%s while getting initial Krb5 credentials for %\"s\n",
 183                                   error_message( code ), code2 ? user : my_name );
 184                 if (my_name)
 185                         free( my_name );
 186                 goto err3;
 187         }
 188
 189         if ((code = krb5DisplayCCache( dname, &ccache, &ccname ))) {
 190                 logError( "%s while getting Krb5 ccache for %\"s\n",
 191                           error_message( code ), dname );
 192                 goto err2;
 193         }
 194
 195         if ((code = krb5_cc_initialize( ctx, ccache, me ))) {
 196                 logError( "%s while initializing Krb5 cache %\"s\n",
 197                           error_message( code ), ccname );
 198                 goto err1;
 199         }
 200
 201         if ((code = krb5_cc_store_cred( ctx, ccache, &my_creds ))) {
 202                 logError( "%s while storing Krb5 credentials to cache %\"s\n",
 203                           error_message( code ), ccname );
 204           err1:
 205                 krb5_cc_close( ctx, ccache );
 206                 free( ccname );
 207           err2:
 208                 krb5_free_cred_contents( ctx, &my_creds );
 209           err3:
 210                 krb5_free_principal( ctx, me );
 211                 return 0;
 212         }
 213
 214         krb5_cc_close( ctx, ccache );
 215         krb5_free_cred_contents( ctx, &my_creds );
 216         krb5_free_principal( ctx, me );
 217         return ccname;
 218 }
 219
 220 void
 221 krb5Destroy( const char *dname )
 222 {
 223         krb5_error_code code;
 224         krb5_ccache ccache;
 225
 226         if (!ctx)
 227                 return;
 228
 229         if ((code = krb5DisplayCCache( dname, &ccache, 0 )))
 230                 logError( "%s while getting Krb5 ccache to destroy\n",
 231                           error_message( code ) );
 232         else {
 233                 if ((code = krb5_cc_destroy( ctx, ccache ))) {
 234                         if (code == KRB5_FCC_NOFILE)
 235                                 debug( "no Kerberos ccache file found to destroy\n" );
 236                         else
 237                                 logError( "%s while destroying Krb5 credentials cache\n",
 238                                           error_message( code ) );
 239                 } else
 240                         debug( "kerberos ccache destroyed\n" );
 241         }
 242 }