source4/auth/kerberos/keytab_copy.c

   1 /*
   2  * Copyright (c) 1997-2004 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * Copyright (c) 2011 Andrew Bartlett
   5  *
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * 3. Neither the name of the Institute nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include "includes.h"
  37 #include "system/kerberos.h"
  38 #include "auth/kerberos/kerberos.h"
  39
  40 static krb5_boolean
  41 compare_keyblock(const krb5_keyblock *a, const krb5_keyblock *b)
  42 {
  43     if (KRB5_KEY_TYPE(a) != KRB5_KEY_TYPE(b) ||
  44         KRB5_KEY_LENGTH(a) != KRB5_KEY_LENGTH(b) ||
  45         memcmp(KRB5_KEY_DATA(a), KRB5_KEY_DATA(b), KRB5_KEY_LENGTH(a)) != 0)
  46         return false;
  47     return true;
  48 }
  49
  50 static krb5_error_code copy_one_entry(krb5_context context,
  51                                       krb5_keytab src_keytab,
  52                                       krb5_keytab dst_keytab,
  53                                       krb5_keytab_entry entry)
  54 {
  55     krb5_error_code ret;
  56     krb5_keytab_entry dummy;
  57
  58     char *name_str;
  59     char *etype_str;
  60     ret = krb5_unparse_name (context, entry.principal, &name_str);
  61     if(ret) {
  62         krb5_set_error_message(context, ret, "krb5_unparse_name");
  63         name_str = NULL; /* XXX */
  64         return ret;
  65     }
  66     ret = smb_krb5_enctype_to_string(context,
  67                                         KRB5_KEY_TYPE(KRB5_KT_KEY(&entry)),
  68                                         &etype_str);
  69     if(ret) {
  70         krb5_set_error_message(context, ret, "krb5_enctype_to_string");
  71         etype_str = NULL; /* XXX */
  72         return ret;
  73     }
  74     ret = krb5_kt_get_entry(context, dst_keytab,
  75                             entry.principal,
  76                             entry.vno,
  77                             KRB5_KEY_TYPE(KRB5_KT_KEY(&entry)),
  78                             &dummy);
  79     if(ret == 0) {
  80         /* this entry is already in the new keytab, so no need to
  81            copy it; if the keyblocks are not the same, something
  82            is weird, so complain about that */
  83         if (!compare_keyblock(KRB5_KT_KEY(&entry), KRB5_KT_KEY(&dummy))) {
  84                 DEBUG(2, ("copy_one_entry: entry with different keyvalue "
  85                           "already exists for %s, keytype %s, kvno %d",
  86                           name_str, etype_str, entry.vno));
  87         }
  88         krb5_kt_free_entry(context, &dummy);
  89         krb5_kt_free_entry (context, &entry);
  90         free(name_str);
  91         free(etype_str);
  92         return ret;
  93     } else if(ret != KRB5_KT_NOTFOUND) {
  94         krb5_set_error_message (context, ret, "fetching %s/%s/%u",
  95                                 name_str, etype_str, entry.vno);
  96         krb5_kt_free_entry (context, &entry);
  97         free(name_str);
  98         free(etype_str);
  99         return ret;
 100     }
 101     ret = krb5_kt_add_entry (context, dst_keytab, &entry);
 102     krb5_kt_free_entry (context, &entry);
 103     if (ret) {
 104         krb5_set_error_message (context, ret, "adding %s/%s/%u",
 105                                 name_str, etype_str, entry.vno);
 106         free(name_str);
 107         free(etype_str);
 108         return ret;
 109     }
 110     free(name_str);
 111     free(etype_str);
 112     return ret;
 113 }
 114
 115 krb5_error_code kt_copy(krb5_context context, const char *from, const char *to)
 116 {
 117     krb5_error_code ret;
 118     krb5_keytab src_keytab, dst_keytab;
 119     krb5_kt_cursor cursor;
 120     krb5_keytab_entry entry;
 121
 122     ret = krb5_kt_resolve (context, from, &src_keytab);
 123     if (ret) {
 124         krb5_set_error_message (context, ret, "resolving src keytab `%s'", from);
 125         return ret;
 126     }
 127
 128     ret = krb5_kt_resolve (context, to, &dst_keytab);
 129     if (ret) {
 130         krb5_kt_close (context, src_keytab);
 131         krb5_set_error_message (context, ret, "resolving dst keytab `%s'", to);
 132         return ret;
 133     }
 134
 135     ret = krb5_kt_start_seq_get (context, src_keytab, &cursor);
 136     if (ret) {
 137         krb5_set_error_message (context, ret, "krb5_kt_start_seq_get %s", from);
 138         goto out;
 139     }
 140
 141     while((ret = krb5_kt_next_entry(context, src_keytab,
 142                                     &entry, &cursor)) == 0) {
 143         ret = copy_one_entry(context, src_keytab, dst_keytab, entry);
 144         if (ret) {
 145             break;
 146         }
 147     }
 148     krb5_kt_end_seq_get (context, src_keytab, &cursor);
 149
 150   out:
 151     krb5_kt_close (context, src_keytab);
 152     krb5_kt_close (context, dst_keytab);
 153     if (ret == KRB5_KT_END) {
 154         return 0;
 155     } else if (ret == 0) {
 156         return EINVAL;
 157     }
 158     return ret;
 159 }
 160
 161 krb5_error_code kt_copy_one_principal(krb5_context context,
 162                                       const char *from,
 163                                       const char *to,
 164                                       const char *principal,
 165                                       krb5_kvno kvno,
 166                                       krb5_enctype *enctypes)
 167 {
 168     krb5_error_code ret;
 169     krb5_keytab src_keytab, dst_keytab;
 170     krb5_keytab_entry entry;
 171     krb5_principal princ;
 172     int i;
 173     bool found_one = false;
 174
 175     ret = krb5_parse_name (context, principal, &princ);
 176     if(ret) {
 177             krb5_set_error_message(context, ret, "krb5_unparse_name");
 178             return ret;
 179     }
 180
 181     ret = krb5_kt_resolve (context, from, &src_keytab);
 182     if (ret) {
 183         krb5_set_error_message(context, ret, "resolving src keytab `%s'", from);
 184         return ret;
 185     }
 186
 187     ret = krb5_kt_resolve (context, to, &dst_keytab);
 188     if (ret) {
 189         krb5_kt_close (context, src_keytab);
 190         krb5_set_error_message(context, ret, "resolving dst keytab `%s'", to);
 191         return ret;
 192     }
 193
 194     for (i=0; enctypes[i]; i++) {
 195         ret = krb5_kt_get_entry(context, src_keytab,
 196                                 princ,
 197                                 kvno,
 198                                 enctypes[i],
 199                                 &entry);
 200         if (ret == KRB5_KT_NOTFOUND) {
 201             continue;
 202         } else if (ret) {
 203             break;
 204         }
 205         found_one = true;
 206         ret = copy_one_entry(context, src_keytab, dst_keytab, entry);
 207         if (ret) {
 208             break;
 209         }
 210     }
 211     if (ret == KRB5_KT_NOTFOUND) {
 212         if (!found_one) {
 213             char *princ_string;
 214             int ret2 = krb5_unparse_name (context, princ, &princ_string);
 215             if (ret2) {
 216                 krb5_set_error_message(context, ret,
 217                                         "failed to fetch principal %s",
 218                                         princ_string);
 219             }
 220         } else {
 221             /* Not finding an enc type is not an error,
 222              * as long as we copied one for the principal */
 223             ret = 0;
 224         }
 225     }
 226
 227     krb5_kt_close (context, src_keytab);
 228     krb5_kt_close (context, dst_keytab);
 229     return ret;
 230 }