- Added simple SSL session cache implementation
- Revamped session resumption handling
diff --git a/library/ssl_cache.c b/library/ssl_cache.c
new file mode 100644
index 0000000..203a4b7
--- /dev/null
+++ b/library/ssl_cache.c
@@ -0,0 +1,152 @@
+/*
+ * SSL session cache implementation
+ *
+ * Copyright (C) 2006-2012, Brainspark B.V.
+ *
+ * This file is part of PolarSSL (http://www.polarssl.org)
+ * Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+/*
+ * These session callbacks use a simple chained list
+ * to store and retrieve the session information.
+ */
+
+#include "polarssl/config.h"
+
+#if defined(POLARSSL_SSL_CACHE_C)
+
+#include "polarssl/ssl_cache.h"
+
+#include <stdlib.h>
+
+void ssl_cache_init( ssl_cache_context *cache )
+{
+ memset( cache, 0, sizeof( ssl_cache_context ) );
+
+ cache->timeout = SSL_CACHE_DEFAULT_TIMEOUT;
+}
+
+int ssl_cache_get( void *data, ssl_session *session )
+{
+ time_t t = time( NULL );
+ ssl_cache_context *cache = (ssl_cache_context *) data;
+ ssl_cache_entry *cur, *entry;
+
+ cur = cache->chain;
+ entry = NULL;
+
+ while( cur != NULL )
+ {
+ entry = cur;
+ cur = cur->next;
+
+ if( cache->timeout != 0 &&
+ (int) ( t - entry->timestamp ) > cache->timeout )
+ continue;
+
+ if( session->ciphersuite != entry->session.ciphersuite ||
+ session->compression != entry->session.compression ||
+ session->length != entry->session.length )
+ continue;
+
+ if( memcmp( session->id, entry->session.id,
+ entry->session.length ) != 0 )
+ continue;
+
+ memcpy( session->master, entry->session.master, 48 );
+ return( 0 );
+ }
+
+ return( 1 );
+}
+
+int ssl_cache_set( void *data, const ssl_session *session )
+{
+ time_t t = time( NULL );
+ ssl_cache_context *cache = (ssl_cache_context *) data;
+ ssl_cache_entry *cur, *prv;
+
+ cur = cache->chain;
+ prv = NULL;
+
+ while( cur != NULL )
+ {
+ if( cache->timeout != 0 &&
+ (int) ( t - cur->timestamp ) > cache->timeout )
+ {
+ cur->timestamp = t;
+ break; /* expired, reuse this slot, update timestamp */
+ }
+
+ if( memcmp( session->id, cur->session.id, cur->session.length ) == 0 )
+ break; /* client reconnected, keep timestamp for session id */
+
+ prv = cur;
+ cur = cur->next;
+ }
+
+ if( cur == NULL )
+ {
+ cur = (ssl_cache_entry *) malloc( sizeof( ssl_cache_entry ) );
+ if( cur == NULL )
+ return( 1 );
+
+ memset( cur, 0, sizeof( ssl_cache_entry ) );
+
+ if( prv == NULL )
+ cache->chain = cur;
+ else
+ prv->next = cur;
+
+ cur->timestamp = t;
+ }
+
+ memcpy( &cur->session, session, sizeof( ssl_session ) );
+
+ // Do not include peer_cert in cache entry
+ //
+ cur->session.peer_cert = NULL;
+
+ return( 0 );
+}
+
+void ssl_cache_set_timeout( ssl_cache_context *cache, int timeout )
+{
+ if( timeout < 0 ) timeout = 0;
+
+ cache->timeout = timeout;
+}
+
+void ssl_cache_free( ssl_cache_context *cache )
+{
+ ssl_cache_entry *cur, *prv;
+
+ cur = cache->chain;
+
+ while( cur != NULL )
+ {
+ prv = cur;
+ cur = cur->next;
+
+ ssl_session_free( &prv->session );
+ free( prv );
+ }
+}
+
+#endif /* POLARSSL_SSL_CACHE_C */
