| /* |
| * SSL session cache implementation |
| * |
| * Copyright The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-2.0 |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may |
| * not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| /* |
| * These session callbacks use a simple chained list |
| * to store and retrieve the session information. |
| */ |
| |
| #include "common.h" |
| |
| #if defined(MBEDTLS_SSL_CACHE_C) |
| |
| #if defined(MBEDTLS_PLATFORM_C) |
| #include "mbedtls/platform.h" |
| #else |
| #include <stdlib.h> |
| #define mbedtls_calloc calloc |
| #define mbedtls_free free |
| #endif |
| |
| #include "mbedtls/ssl_cache.h" |
| #include "ssl_misc.h" |
| |
| #include <string.h> |
| |
| void mbedtls_ssl_cache_init( mbedtls_ssl_cache_context *cache ) |
| { |
| memset( cache, 0, sizeof( mbedtls_ssl_cache_context ) ); |
| |
| cache->timeout = MBEDTLS_SSL_CACHE_DEFAULT_TIMEOUT; |
| cache->max_entries = MBEDTLS_SSL_CACHE_DEFAULT_MAX_ENTRIES; |
| |
| #if defined(MBEDTLS_THREADING_C) |
| mbedtls_mutex_init( &cache->mutex ); |
| #endif |
| } |
| |
| int mbedtls_ssl_cache_get( void *data, mbedtls_ssl_session *session ) |
| { |
| int ret = 1; |
| #if defined(MBEDTLS_HAVE_TIME) |
| mbedtls_time_t t = mbedtls_time( NULL ); |
| #endif |
| mbedtls_ssl_cache_context *cache = (mbedtls_ssl_cache_context *) data; |
| mbedtls_ssl_cache_entry *cur, *entry; |
| |
| #if defined(MBEDTLS_THREADING_C) |
| if( mbedtls_mutex_lock( &cache->mutex ) != 0 ) |
| return( 1 ); |
| #endif |
| |
| cur = cache->chain; |
| entry = NULL; |
| |
| while( cur != NULL ) |
| { |
| entry = cur; |
| cur = cur->next; |
| |
| #if defined(MBEDTLS_HAVE_TIME) |
| if( cache->timeout != 0 && |
| (int) ( t - entry->timestamp ) > cache->timeout ) |
| continue; |
| #endif |
| |
| if( session->ciphersuite != entry->session.ciphersuite || |
| session->compression != entry->session.compression || |
| session->id_len != entry->session.id_len ) |
| continue; |
| |
| if( memcmp( session->id, entry->session.id, |
| entry->session.id_len ) != 0 ) |
| continue; |
| |
| ret = mbedtls_ssl_session_copy( session, &entry->session ); |
| if( ret != 0 ) |
| { |
| ret = 1; |
| goto exit; |
| } |
| |
| #if defined(MBEDTLS_X509_CRT_PARSE_C) && \ |
| defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) |
| /* |
| * Restore peer certificate (without rest of the original chain) |
| */ |
| if( entry->peer_cert.p != NULL ) |
| { |
| /* `session->peer_cert` is NULL after the call to |
| * mbedtls_ssl_session_copy(), because cache entries |
| * have the `peer_cert` field set to NULL. */ |
| |
| if( ( session->peer_cert = mbedtls_calloc( 1, |
| sizeof(mbedtls_x509_crt) ) ) == NULL ) |
| { |
| ret = 1; |
| goto exit; |
| } |
| |
| mbedtls_x509_crt_init( session->peer_cert ); |
| if( mbedtls_x509_crt_parse( session->peer_cert, entry->peer_cert.p, |
| entry->peer_cert.len ) != 0 ) |
| { |
| mbedtls_free( session->peer_cert ); |
| session->peer_cert = NULL; |
| ret = 1; |
| goto exit; |
| } |
| } |
| #endif /* MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ |
| |
| ret = 0; |
| goto exit; |
| } |
| |
| exit: |
| #if defined(MBEDTLS_THREADING_C) |
| if( mbedtls_mutex_unlock( &cache->mutex ) != 0 ) |
| ret = 1; |
| #endif |
| |
| return( ret ); |
| } |
| |
| int mbedtls_ssl_cache_set( void *data, const mbedtls_ssl_session *session ) |
| { |
| int ret = 1; |
| #if defined(MBEDTLS_HAVE_TIME) |
| mbedtls_time_t t = mbedtls_time( NULL ), oldest = 0; |
| mbedtls_ssl_cache_entry *old = NULL; |
| #endif |
| mbedtls_ssl_cache_context *cache = (mbedtls_ssl_cache_context *) data; |
| mbedtls_ssl_cache_entry *cur, *prv; |
| int count = 0; |
| |
| #if defined(MBEDTLS_THREADING_C) |
| if( ( ret = mbedtls_mutex_lock( &cache->mutex ) ) != 0 ) |
| return( ret ); |
| #endif |
| |
| cur = cache->chain; |
| prv = NULL; |
| |
| while( cur != NULL ) |
| { |
| count++; |
| |
| #if defined(MBEDTLS_HAVE_TIME) |
| if( cache->timeout != 0 && |
| (int) ( t - cur->timestamp ) > cache->timeout ) |
| { |
| cur->timestamp = t; |
| break; /* expired, reuse this slot, update timestamp */ |
| } |
| #endif |
| |
| if( memcmp( session->id, cur->session.id, cur->session.id_len ) == 0 ) |
| break; /* client reconnected, keep timestamp for session id */ |
| |
| #if defined(MBEDTLS_HAVE_TIME) |
| if( oldest == 0 || cur->timestamp < oldest ) |
| { |
| oldest = cur->timestamp; |
| old = cur; |
| } |
| #endif |
| |
| prv = cur; |
| cur = cur->next; |
| } |
| |
| if( cur == NULL ) |
| { |
| #if defined(MBEDTLS_HAVE_TIME) |
| /* |
| * Reuse oldest entry if max_entries reached |
| */ |
| if( count >= cache->max_entries ) |
| { |
| if( old == NULL ) |
| { |
| ret = 1; |
| goto exit; |
| } |
| |
| cur = old; |
| } |
| #else /* MBEDTLS_HAVE_TIME */ |
| /* |
| * Reuse first entry in chain if max_entries reached, |
| * but move to last place |
| */ |
| if( count >= cache->max_entries ) |
| { |
| if( cache->chain == NULL ) |
| { |
| ret = 1; |
| goto exit; |
| } |
| |
| cur = cache->chain; |
| cache->chain = cur->next; |
| cur->next = NULL; |
| prv->next = cur; |
| } |
| #endif /* MBEDTLS_HAVE_TIME */ |
| else |
| { |
| /* |
| * max_entries not reached, create new entry |
| */ |
| cur = mbedtls_calloc( 1, sizeof(mbedtls_ssl_cache_entry) ); |
| if( cur == NULL ) |
| { |
| ret = 1; |
| goto exit; |
| } |
| |
| if( prv == NULL ) |
| cache->chain = cur; |
| else |
| prv->next = cur; |
| } |
| |
| #if defined(MBEDTLS_HAVE_TIME) |
| cur->timestamp = t; |
| #endif |
| } |
| |
| #if defined(MBEDTLS_X509_CRT_PARSE_C) && \ |
| defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) |
| /* |
| * If we're reusing an entry, free its certificate first |
| */ |
| if( cur->peer_cert.p != NULL ) |
| { |
| mbedtls_free( cur->peer_cert.p ); |
| memset( &cur->peer_cert, 0, sizeof(mbedtls_x509_buf) ); |
| } |
| #endif /* MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ |
| |
| /* Copy the entire session; this temporarily makes a copy of the |
| * X.509 CRT structure even though we only want to store the raw CRT. |
| * This inefficiency will go away as soon as we implement on-demand |
| * parsing of CRTs, in which case there's no need for the `peer_cert` |
| * field anymore in the first place, and we're done after this call. */ |
| ret = mbedtls_ssl_session_copy( &cur->session, session ); |
| if( ret != 0 ) |
| { |
| ret = 1; |
| goto exit; |
| } |
| |
| #if defined(MBEDTLS_X509_CRT_PARSE_C) && \ |
| defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) |
| /* If present, free the X.509 structure and only store the raw CRT data. */ |
| if( cur->session.peer_cert != NULL ) |
| { |
| cur->peer_cert.p = |
| mbedtls_calloc( 1, cur->session.peer_cert->raw.len ); |
| if( cur->peer_cert.p == NULL ) |
| { |
| ret = 1; |
| goto exit; |
| } |
| |
| memcpy( cur->peer_cert.p, |
| cur->session.peer_cert->raw.p, |
| cur->session.peer_cert->raw.len ); |
| cur->peer_cert.len = session->peer_cert->raw.len; |
| |
| mbedtls_x509_crt_free( cur->session.peer_cert ); |
| mbedtls_free( cur->session.peer_cert ); |
| cur->session.peer_cert = NULL; |
| } |
| #endif /* MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ |
| |
| ret = 0; |
| |
| exit: |
| #if defined(MBEDTLS_THREADING_C) |
| if( mbedtls_mutex_unlock( &cache->mutex ) != 0 ) |
| ret = 1; |
| #endif |
| |
| return( ret ); |
| } |
| |
| #if defined(MBEDTLS_HAVE_TIME) |
| void mbedtls_ssl_cache_set_timeout( mbedtls_ssl_cache_context *cache, int timeout ) |
| { |
| if( timeout < 0 ) timeout = 0; |
| |
| cache->timeout = timeout; |
| } |
| #endif /* MBEDTLS_HAVE_TIME */ |
| |
| void mbedtls_ssl_cache_set_max_entries( mbedtls_ssl_cache_context *cache, int max ) |
| { |
| if( max < 0 ) max = 0; |
| |
| cache->max_entries = max; |
| } |
| |
| void mbedtls_ssl_cache_free( mbedtls_ssl_cache_context *cache ) |
| { |
| mbedtls_ssl_cache_entry *cur, *prv; |
| |
| cur = cache->chain; |
| |
| while( cur != NULL ) |
| { |
| prv = cur; |
| cur = cur->next; |
| |
| mbedtls_ssl_session_free( &prv->session ); |
| |
| #if defined(MBEDTLS_X509_CRT_PARSE_C) && \ |
| defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) |
| mbedtls_free( prv->peer_cert.p ); |
| #endif /* MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ |
| |
| mbedtls_free( prv ); |
| } |
| |
| #if defined(MBEDTLS_THREADING_C) |
| mbedtls_mutex_free( &cache->mutex ); |
| #endif |
| cache->chain = NULL; |
| } |
| |
| #endif /* MBEDTLS_SSL_CACHE_C */ |