src/resume.c

   1 /* resume.c --- Handle the details of TLS session resumption.
   2  * Copyright (C) 2002, 2003  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 2 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, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  19  *
  20  */
  21
  22 /* Note: only use syslog to report errors in this file. */
  23
  24 /* Get Shishid stuff. */
  25 #include "kdc.h"
  26
  27 typedef struct
  28 {
  29   char *id;
  30   size_t id_size;
  31   char *data;
  32   size_t data_size;
  33 } CACHE;
  34
  35 static CACHE *cache_db;
  36 static size_t cache_db_ptr = 0;
  37 static size_t cache_db_size = 0;
  38
  39 int
  40 resume_db_store (void *dbf, gnutls_datum key, gnutls_datum data)
  41 {
  42   if (cache_db_size == 0)
  43     return -1;
  44
  45   cache_db[cache_db_ptr].id = xrealloc (cache_db[cache_db_ptr].id, key.size);
  46   memcpy (cache_db[cache_db_ptr].id, key.data, key.size);
  47   cache_db[cache_db_ptr].id_size = key.size;
  48
  49   cache_db[cache_db_ptr].data = xrealloc (cache_db[cache_db_ptr].data,
  50                                           data.size);
  51   memcpy (cache_db[cache_db_ptr].data, data.data, data.size);
  52   cache_db[cache_db_ptr].data_size = data.size;
  53
  54   cache_db_ptr++;
  55   cache_db_ptr %= cache_db_size;
  56
  57   return 0;
  58 }
  59
  60 gnutls_datum
  61 resume_db_fetch (void *dbf, gnutls_datum key)
  62 {
  63   gnutls_datum res = { NULL, 0 };
  64   size_t i;
  65
  66   for (i = 0; i < cache_db_size; i++)
  67     if (key.size == cache_db[i].id_size &&
  68         memcmp (key.data, cache_db[i].id, key.size) == 0)
  69       {
  70         res.size = cache_db[i].data_size;
  71
  72         res.data = gnutls_malloc (res.size);
  73         if (res.data == NULL)
  74           return res;
  75
  76         memcpy (res.data, cache_db[i].data, res.size);
  77
  78         return res;
  79       }
  80
  81   return res;
  82 }
  83
  84 int
  85 resume_db_delete (void *dbf, gnutls_datum key)
  86 {
  87   size_t i;
  88
  89   for (i = 0; i < cache_db_size; i++)
  90     if (key.size == cache_db[i].id_size &&
  91         memcmp (key.data, cache_db[i].id, key.size) == 0)
  92       {
  93         cache_db[i].id_size = 0;
  94         cache_db[i].data_size = 0;
  95
  96         return 0;
  97       }
  98
  99   return -1;
 100 }
 101
 102 void
 103 resume_db_init (size_t nconnections)
 104 {
 105   resume_db_done ();
 106   cache_db = xcalloc (nconnections, sizeof (*cache_db));
 107   cache_db_size = nconnections;
 108 }
 109
 110 void
 111 resume_db_done (void)
 112 {
 113   size_t i;
 114
 115   for (i = 0; i < cache_db_size; i++)
 116     {
 117       if (cache_db[i].id)
 118         free (cache_db[i].id);
 119       if (cache_db[i].data)
 120         free (cache_db[i].data);
 121     }
 122
 123   if (cache_db)
 124     free (cache_db);
 125 }