lib/krb5/verify_init.c

   1 /*
   2  * Copyright (c) 1997 - 2002 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 "krb5_locl.h"
  35
  36 RCSID("$Id$");
  37
  38 void KRB5_LIB_FUNCTION
  39 krb5_verify_init_creds_opt_init(krb5_verify_init_creds_opt *options)
  40 {
  41     memset (options, 0, sizeof(*options));
  42 }
  43
  44 void KRB5_LIB_FUNCTION
  45 krb5_verify_init_creds_opt_set_ap_req_nofail(krb5_verify_init_creds_opt *options,
  46                                              int ap_req_nofail)
  47 {
  48     options->flags |= KRB5_VERIFY_INIT_CREDS_OPT_AP_REQ_NOFAIL;
  49     options->ap_req_nofail = ap_req_nofail;
  50 }
  51
  52 /*
  53  *
  54  */
  55
  56 static krb5_boolean
  57 fail_verify_is_ok (krb5_context context,
  58                    krb5_verify_init_creds_opt *options)
  59 {
  60     if ((options->flags & KRB5_VERIFY_INIT_CREDS_OPT_AP_REQ_NOFAIL
  61          && options->ap_req_nofail != 0)
  62         || krb5_config_get_bool (context,
  63                                  NULL,
  64                                  "libdefaults",
  65                                  "verify_ap_req_nofail",
  66                                  NULL))
  67         return FALSE;
  68     else
  69         return TRUE;
  70 }
  71
  72 krb5_error_code KRB5_LIB_FUNCTION
  73 krb5_verify_init_creds(krb5_context context,
  74                        krb5_creds *creds,
  75                        krb5_principal ap_req_server,
  76                        krb5_keytab ap_req_keytab,
  77                        krb5_ccache *ccache,
  78                        krb5_verify_init_creds_opt *options)
  79 {
  80     krb5_error_code ret;
  81     krb5_data req;
  82     krb5_ccache local_ccache = NULL;
  83     krb5_creds *new_creds = NULL;
  84     krb5_auth_context auth_context = NULL;
  85     krb5_principal server = NULL;
  86     krb5_keytab keytab = NULL;
  87
  88     krb5_data_zero (&req);
  89
  90     if (ap_req_server == NULL) {
  91         char local_hostname[MAXHOSTNAMELEN];
  92
  93         if (gethostname (local_hostname, sizeof(local_hostname)) < 0) {
  94             ret = errno;
  95             krb5_set_error_string (context, "gethostname: %s",
  96                                    strerror(ret));
  97             return ret;
  98         }
  99
 100         ret = krb5_sname_to_principal (context,
 101                                        local_hostname,
 102                                        "host",
 103                                        KRB5_NT_SRV_HST,
 104                                        &server);
 105         if (ret)
 106             goto cleanup;
 107     } else
 108         server = ap_req_server;
 109
 110     if (ap_req_keytab == NULL) {
 111         ret = krb5_kt_default (context, &keytab);
 112         if (ret)
 113             goto cleanup;
 114     } else
 115         keytab = ap_req_keytab;
 116
 117     if (ccache && *ccache)
 118         local_ccache = *ccache;
 119     else {
 120         ret = krb5_cc_gen_new (context, &krb5_mcc_ops, &local_ccache);
 121         if (ret)
 122             goto cleanup;
 123         ret = krb5_cc_initialize (context,
 124                                   local_ccache,
 125                                   creds->client);
 126         if (ret)
 127             goto cleanup;
 128         ret = krb5_cc_store_cred (context,
 129                                   local_ccache,
 130                                   creds);
 131         if (ret)
 132             goto cleanup;
 133     }
 134
 135     if (!krb5_principal_compare (context, server, creds->server)) {
 136         krb5_creds match_cred;
 137
 138         memset (&match_cred, 0, sizeof(match_cred));
 139
 140         match_cred.client = creds->client;
 141         match_cred.server = server;
 142
 143         ret = krb5_get_credentials (context,
 144                                     0,
 145                                     local_ccache,
 146                                     &match_cred,
 147                                     &new_creds);
 148         if (ret) {
 149             if (fail_verify_is_ok (context, options))
 150                 ret = 0;
 151             goto cleanup;
 152         }
 153         creds = new_creds;
 154     }
 155
 156     ret = krb5_mk_req_extended (context,
 157                                 &auth_context,
 158                                 0,
 159                                 NULL,
 160                                 creds,
 161                                 &req);
 162
 163     krb5_auth_con_free (context, auth_context);
 164     auth_context = NULL;
 165
 166     if (ret)
 167         goto cleanup;
 168
 169     ret = krb5_rd_req (context,
 170                        &auth_context,
 171                        &req,
 172                        server,
 173                        keytab,
 174                        0,
 175                        NULL);
 176
 177     if (ret == KRB5_KT_NOTFOUND && fail_verify_is_ok (context, options))
 178         ret = 0;
 179 cleanup:
 180     if (auth_context)
 181         krb5_auth_con_free (context, auth_context);
 182     krb5_data_free (&req);
 183     if (new_creds != NULL)
 184         krb5_free_creds (context, new_creds);
 185     if (ap_req_server == NULL && server)
 186         krb5_free_principal (context, server);
 187     if (ap_req_keytab == NULL && keytab)
 188         krb5_kt_close (context, keytab);
 189     if (local_ccache != NULL
 190         &&
 191         (ccache == NULL
 192          || (ret != 0 && *ccache == NULL)))
 193         krb5_cc_destroy (context, local_ccache);
 194
 195     if (ret == 0 && ccache != NULL && *ccache == NULL)
 196         *ccache = local_ccache;
 197
 198     return ret;
 199 }