src/resume.c

   1 /* resume.c --- Handle the details of TLS session resumption.
   2  * Copyright (C) 2002, 2003, 2007  Simon Josefsson
   3  *
   4  * This file is part of Shishi.
   5  *
   6  * Shishi is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * Shishi is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with Shishi; if not, see http://www.gnu.org/licenses or write
  18  * to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
  19  * Floor, Boston, MA 02110-1301, USA
  20  *
  21  */
  22
  23 /* Note: only use syslog to report errors in this file. */
  24
  25 /* Get Shishid stuff. */
  26 #include "kdc.h"
  27
  28 typedef struct
  29 {
  30   char *id;
  31   size_t id_size;
  32   char *data;
  33   size_t data_size;
  34 } CACHE;
  35
  36 static CACHE *cache_db;
  37 static size_t cache_db_ptr = 0;
  38 static size_t cache_db_size = 0;
  39
  40 int
  41 resume_db_store (void *dbf, gnutls_datum key, gnutls_datum data)
  42 {
  43   if (cache_db_size == 0)
  44     return -1;
  45
  46   cache_db[cache_db_ptr].id = xrealloc (cache_db[cache_db_ptr].id, key.size);
  47   memcpy (cache_db[cache_db_ptr].id, key.data, key.size);
  48   cache_db[cache_db_ptr].id_size = key.size;
  49
  50   cache_db[cache_db_ptr].data = xrealloc (cache_db[cache_db_ptr].data,
  51                                           data.size);
  52   memcpy (cache_db[cache_db_ptr].data, data.data, data.size);
  53   cache_db[cache_db_ptr].data_size = data.size;
  54
  55   cache_db_ptr++;
  56   cache_db_ptr %= cache_db_size;
  57
  58   return 0;
  59 }
  60
  61 gnutls_datum
  62 resume_db_fetch (void *dbf, gnutls_datum key)
  63 {
  64   gnutls_datum res = { NULL, 0 };
  65   size_t i;
  66
  67   for (i = 0; i < cache_db_size; i++)
  68     if (key.size == cache_db[i].id_size &&
  69         memcmp (key.data, cache_db[i].id, key.size) == 0)
  70       {
  71         res.size = cache_db[i].data_size;
  72
  73         res.data = gnutls_malloc (res.size);
  74         if (res.data == NULL)
  75           return res;
  76
  77         memcpy (res.data, cache_db[i].data, res.size);
  78
  79         return res;
  80       }
  81
  82   return res;
  83 }
  84
  85 int
  86 resume_db_delete (void *dbf, gnutls_datum key)
  87 {
  88   size_t i;
  89
  90   for (i = 0; i < cache_db_size; i++)
  91     if (key.size == cache_db[i].id_size &&
  92         memcmp (key.data, cache_db[i].id, key.size) == 0)
  93       {
  94         cache_db[i].id_size = 0;
  95         cache_db[i].data_size = 0;
  96
  97         return 0;
  98       }
  99
 100   return -1;
 101 }
 102
 103 void
 104 resume_db_init (size_t nconnections)
 105 {
 106   resume_db_done ();
 107   cache_db = xcalloc (nconnections, sizeof (*cache_db));
 108   cache_db_size = nconnections;
 109 }
 110
 111 void
 112 resume_db_done (void)
 113 {
 114   size_t i;
 115
 116   for (i = 0; i < cache_db_size; i++)
 117     {
 118       if (cache_db[i].id)
 119         free (cache_db[i].id);
 120       if (cache_db[i].data)
 121         free (cache_db[i].data);
 122     }
 123
 124   if (cache_db)
 125     free (cache_db);
 126 }