lib/krb5/keytab_memory.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 "krb5_locl.h"
  35
  36 RCSID("$Id$");
  37
  38 /* memory operations -------------------------------------------- */
  39
  40 struct mkt_data {
  41     krb5_keytab_entry *entries;
  42     int num_entries;
  43 };
  44
  45 static krb5_error_code
  46 mkt_resolve(krb5_context context, const char *name, krb5_keytab id)
  47 {
  48     struct mkt_data *d;
  49     d = malloc(sizeof(*d));
  50     if(d == NULL) {
  51         krb5_set_error_string (context, "malloc: out of memory");
  52         return ENOMEM;
  53     }
  54     d->entries = NULL;
  55     d->num_entries = 0;
  56     id->data = d;
  57     return 0;
  58 }
  59
  60 static krb5_error_code
  61 mkt_close(krb5_context context, krb5_keytab id)
  62 {
  63     struct mkt_data *d = id->data;
  64     int i;
  65     for(i = 0; i < d->num_entries; i++)
  66         krb5_kt_free_entry(context, &d->entries[i]);
  67     free(d->entries);
  68     free(d);
  69     return 0;
  70 }
  71
  72 static krb5_error_code
  73 mkt_get_name(krb5_context context,
  74              krb5_keytab id,
  75              char *name,
  76              size_t namesize)
  77 {
  78     strlcpy(name, "", namesize);
  79     return 0;
  80 }
  81
  82 static krb5_error_code
  83 mkt_start_seq_get(krb5_context context,
  84                   krb5_keytab id,
  85                   krb5_kt_cursor *c)
  86 {
  87     /* XXX */
  88     c->fd = 0;
  89     return 0;
  90 }
  91
  92 static krb5_error_code
  93 mkt_next_entry(krb5_context context,
  94                krb5_keytab id,
  95                krb5_keytab_entry *entry,
  96                krb5_kt_cursor *c)
  97 {
  98     struct mkt_data *d = id->data;
  99     if(c->fd >= d->num_entries)
 100         return KRB5_KT_END;
 101     return krb5_kt_copy_entry_contents(context, &d->entries[c->fd++], entry);
 102 }
 103
 104 static krb5_error_code
 105 mkt_end_seq_get(krb5_context context,
 106                 krb5_keytab id,
 107                 krb5_kt_cursor *cursor)
 108 {
 109     return 0;
 110 }
 111
 112 static krb5_error_code
 113 mkt_add_entry(krb5_context context,
 114               krb5_keytab id,
 115               krb5_keytab_entry *entry)
 116 {
 117     struct mkt_data *d = id->data;
 118     krb5_keytab_entry *tmp;
 119     tmp = realloc(d->entries, (d->num_entries + 1) * sizeof(*d->entries));
 120     if(tmp == NULL) {
 121         krb5_set_error_string (context, "malloc: out of memory");
 122         return ENOMEM;
 123     }
 124     d->entries = tmp;
 125     return krb5_kt_copy_entry_contents(context, entry,
 126                                        &d->entries[d->num_entries++]);
 127 }
 128
 129 static krb5_error_code
 130 mkt_remove_entry(krb5_context context,
 131                  krb5_keytab id,
 132                  krb5_keytab_entry *entry)
 133 {
 134     struct mkt_data *d = id->data;
 135     krb5_keytab_entry *e, *end;
 136     int found = 0;
 137
 138     if (d->num_entries == 0) {
 139         krb5_clear_error_string(context);
 140         return KRB5_KT_NOTFOUND;
 141     }
 142
 143     /* do this backwards to minimize copying */
 144     for(end = d->entries + d->num_entries, e = end - 1; e >= d->entries; e--) {
 145         if(krb5_kt_compare(context, e, entry->principal,
 146                            entry->vno, entry->keyblock.keytype)) {
 147             krb5_kt_free_entry(context, e);
 148             memmove(e, e + 1, (end - e - 1) * sizeof(*e));
 149             memset(end - 1, 0, sizeof(*end));
 150             d->num_entries--;
 151             end--;
 152             found = 1;
 153         }
 154     }
 155     if (!found) {
 156         krb5_clear_error_string (context);
 157         return KRB5_KT_NOTFOUND;
 158     }
 159     e = realloc(d->entries, d->num_entries * sizeof(*d->entries));
 160     if(e != NULL || d->num_entries == 0)
 161         d->entries = e;
 162     return 0;
 163 }
 164
 165 const krb5_kt_ops krb5_mkt_ops = {
 166     "MEMORY",
 167     mkt_resolve,
 168     mkt_get_name,
 169     mkt_close,
 170     NULL, /* get */
 171     mkt_start_seq_get,
 172     mkt_next_entry,
 173     mkt_end_seq_get,
 174     mkt_add_entry,
 175     mkt_remove_entry
 176 };