kdc/misc.c

   1 /*
   2  * Copyright (c) 1997 - 2001 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "kdc_locl.h"
  35
  36 struct timeval _kdc_now;
  37
  38 krb5_error_code
  39 _kdc_db_fetch(krb5_context context,
  40               krb5_kdc_configuration *config,
  41               krb5_const_principal principal,
  42               unsigned flags,
  43               krb5uint32 *kvno_ptr,
  44               HDB **db,
  45               hdb_entry_ex **h)
  46 {
  47     hdb_entry_ex *ent;
  48     krb5_error_code ret = HDB_ERR_NOENTRY;
  49     int i;
  50     unsigned kvno = 0;
  51
  52     if (kvno_ptr) {
  53             kvno = *kvno_ptr;
  54             flags |= HDB_F_KVNO_SPECIFIED;
  55     }
  56
  57     ent = calloc (1, sizeof (*ent));
  58     if (ent == NULL) {
  59         krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
  60         return ENOMEM;
  61     }
  62
  63     for(i = 0; i < config->num_db; i++) {
  64         krb5_principal enterprise_principal = NULL;
  65         if (!(config->db[i]->hdb_capability_flags & HDB_CAP_F_HANDLE_ENTERPRISE_PRINCIPAL)
  66             && principal->name.name_type == KRB5_NT_ENTERPRISE_PRINCIPAL) {
  67             if (principal->name.name_string.len != 1) {
  68                 ret = KRB5_PARSE_MALFORMED;
  69                 krb5_set_error_message(context, ret,
  70                                        "malformed request: "
  71                                        "enterprise name with %d name components",
  72                                        principal->name.name_string.len);
  73                 free(ent);
  74                 return ret;
  75             }
  76             ret = krb5_parse_name(context, principal->name.name_string.val[0],
  77                                   &enterprise_principal);
  78             if (ret) {
  79                 free(ent);
  80                 return ret;
  81             }
  82
  83             principal = enterprise_principal;
  84         }
  85
  86         ret = config->db[i]->hdb_open(context, config->db[i], O_RDONLY, 0);
  87         if (ret) {
  88             const char *msg = krb5_get_error_message(context, ret);
  89             kdc_log(context, config, 0, "Failed to open database: %s", msg);
  90             krb5_free_error_message(context, msg);
  91             continue;
  92         }
  93
  94         ret = config->db[i]->hdb_fetch_kvno(context,
  95                                             config->db[i],
  96                                             principal,
  97                                             flags | HDB_F_DECRYPT,
  98                                             kvno,
  99                                             ent);
 100
 101         krb5_free_principal(context, enterprise_principal);
 102
 103         config->db[i]->hdb_close(context, config->db[i]);
 104         if(ret == 0) {
 105             if (db)
 106                 *db = config->db[i];
 107             *h = ent;
 108             return 0;
 109         }
 110     }
 111     free(ent);
 112     krb5_set_error_message(context, ret,
 113                            "no such entry found in hdb");
 114     return ret;
 115 }
 116
 117 void
 118 _kdc_free_ent(krb5_context context, hdb_entry_ex *ent)
 119 {
 120     hdb_free_entry (context, ent);
 121     free (ent);
 122 }
 123
 124 /*
 125  * Use the order list of preferred encryption types and sort the
 126  * available keys and return the most preferred key.
 127  */
 128
 129 krb5_error_code
 130 _kdc_get_preferred_key(krb5_context context,
 131                        krb5_kdc_configuration *config,
 132                        hdb_entry_ex *h,
 133                        const char *name,
 134                        krb5_enctype *enctype,
 135                        Key **key)
 136 {
 137     krb5_error_code ret;
 138     int i;
 139
 140     if (config->use_strongest_server_key) {
 141         const krb5_enctype *p = krb5_kerberos_enctypes(context);
 142
 143         for (i = 0; p[i] != ETYPE_NULL; i++) {
 144             if (krb5_enctype_valid(context, p[i]) != 0)
 145                 continue;
 146             ret = hdb_enctype2key(context, &h->entry, p[i], key);
 147             if (ret != 0)
 148                 continue;
 149             if (enctype != NULL)
 150                 *enctype = p[i];
 151             return 0;
 152         }
 153     } else {
 154         *key = NULL;
 155
 156         for (i = 0; i < h->entry.keys.len; i++) {
 157             if (krb5_enctype_valid(context, h->entry.keys.val[i].key.keytype)
 158                 != 0)
 159                 continue;
 160             ret = hdb_enctype2key(context, &h->entry,
 161                 h->entry.keys.val[i].key.keytype, key);
 162             if (ret != 0)
 163                 continue;
 164             if (enctype != NULL)
 165                 *enctype = (*key)->key.keytype;
 166             return 0;
 167         }
 168     }
 169
 170     krb5_set_error_message(context, EINVAL,
 171                            "No valid kerberos key found for %s", name);
 172     return EINVAL; /* XXX */
 173 }
 174