lib/krb5_wrap/keytab_util.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 "krb5_samba.h"
  38
  39 static krb5_boolean
  40 compare_keyblock(const krb5_keyblock *a, const krb5_keyblock *b)
  41 {
  42     if (KRB5_KEY_TYPE(a) != KRB5_KEY_TYPE(b) ||
  43         KRB5_KEY_LENGTH(a) != KRB5_KEY_LENGTH(b) ||
  44         memcmp(KRB5_KEY_DATA(a), KRB5_KEY_DATA(b), KRB5_KEY_LENGTH(a)) != 0)
  45         return false;
  46     return true;
  47 }
  48
  49 static krb5_error_code copy_one_entry(krb5_context context,
  50                                       krb5_keytab src_keytab,
  51                                       krb5_keytab dst_keytab,
  52                                       krb5_keytab_entry entry)
  53 {
  54     krb5_error_code ret;
  55     krb5_keytab_entry dummy;
  56
  57     char *name_str;
  58     char *etype_str;
  59     ret = krb5_unparse_name (context, entry.principal, &name_str);
  60     if(ret) {
  61         krb5_set_error_message(context, ret, "krb5_unparse_name");
  62         name_str = NULL; /* XXX */
  63         return ret;
  64     }
  65     ret = smb_krb5_enctype_to_string(context,
  66                                         KRB5_KEY_TYPE(KRB5_KT_KEY(&entry)),
  67                                         &etype_str);
  68     if(ret) {
  69         krb5_free_unparsed_name(context, name_str);
  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                                       const 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_free_principal(context, princ);
 184         krb5_set_error_message(context, ret, "resolving src keytab `%s'", from);
 185         return ret;
 186     }
 187
 188     ret = krb5_kt_resolve (context, to, &dst_keytab);
 189     if (ret) {
 190         krb5_free_principal(context, princ);
 191         krb5_kt_close (context, src_keytab);
 192         krb5_set_error_message(context, ret, "resolving dst keytab `%s'", to);
 193         return ret;
 194     }
 195
 196     for (i=0; enctypes[i]; i++) {
 197         ret = krb5_kt_get_entry(context, src_keytab,
 198                                 princ,
 199                                 kvno,
 200                                 enctypes[i],
 201                                 &entry);
 202         if (ret == KRB5_KT_NOTFOUND) {
 203             continue;
 204         } else if (ret) {
 205             break;
 206         }
 207         found_one = true;
 208         ret = copy_one_entry(context, src_keytab, dst_keytab, entry);
 209         if (ret) {
 210             break;
 211         }
 212     }
 213     if (ret == KRB5_KT_NOTFOUND) {
 214         if (!found_one) {
 215             char *princ_string;
 216             int ret2 = krb5_unparse_name (context, princ, &princ_string);
 217             if (ret2) {
 218                 krb5_set_error_message(context, ret,
 219                                         "failed to fetch principal %s",
 220                                         princ_string);
 221             }
 222         } else {
 223             /* Not finding an enc type is not an error,
 224              * as long as we copied one for the principal */
 225             ret = 0;
 226         }
 227     }
 228
 229     krb5_free_principal(context, princ);
 230     krb5_kt_close (context, src_keytab);
 231     krb5_kt_close (context, dst_keytab);
 232     return ret;
 233 }
 234
 235 #if !defined(HAVE_KRB5_KT_COMPARE)
 236 krb5_boolean smb_krb5_kt_compare(krb5_context context,
 237                                  krb5_keytab_entry *entry,
 238                                  krb5_const_principal principal,
 239                                  krb5_kvno kvno,
 240                                  krb5_enctype enctype)
 241 {
 242         if (principal) {
 243                 if (!krb5_principal_compare(context,
 244                                             entry->principal, principal)) {
 245                         return false;
 246                 }
 247         }
 248         if (kvno) {
 249                 if (entry->vno != kvno) {
 250                         return false;
 251                 }
 252         }
 253         if (enctype) {
 254                 if (KRB5_KEY_TYPE(KRB5_KT_KEY(entry)) != enctype) {
 255                         return false;
 256                 }
 257         }
 258
 259         return true;
 260 }
 261 #endif
 262