Simon Cooksey / mbed-os

Pinned to some recent date

features/mbedtls/src/ssl_ticket.c@0:fb7af294d5d9, 2016-11-17 (annotated)

Committer:
Simon Cooksey
Date:
Thu Nov 17 16:43:53 2016 +0000
Revision:
0:fb7af294d5d9
Initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Simon Cooksey 0:fb7af294d5d9 1 /*
Simon Cooksey 0:fb7af294d5d9 2 * TLS server tickets callbacks implementation
Simon Cooksey 0:fb7af294d5d9 3 *
Simon Cooksey 0:fb7af294d5d9 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
Simon Cooksey 0:fb7af294d5d9 5 * SPDX-License-Identifier: Apache-2.0
Simon Cooksey 0:fb7af294d5d9 6 *
Simon Cooksey 0:fb7af294d5d9 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
Simon Cooksey 0:fb7af294d5d9 8 * not use this file except in compliance with the License.
Simon Cooksey 0:fb7af294d5d9 9 * You may obtain a copy of the License at
Simon Cooksey 0:fb7af294d5d9 10 *
Simon Cooksey 0:fb7af294d5d9 11 * http://www.apache.org/licenses/LICENSE-2.0
Simon Cooksey 0:fb7af294d5d9 12 *
Simon Cooksey 0:fb7af294d5d9 13 * Unless required by applicable law or agreed to in writing, software
Simon Cooksey 0:fb7af294d5d9 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
Simon Cooksey 0:fb7af294d5d9 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
Simon Cooksey 0:fb7af294d5d9 16 * See the License for the specific language governing permissions and
Simon Cooksey 0:fb7af294d5d9 17 * limitations under the License.
Simon Cooksey 0:fb7af294d5d9 18 *
Simon Cooksey 0:fb7af294d5d9 19 * This file is part of mbed TLS (https://tls.mbed.org)
Simon Cooksey 0:fb7af294d5d9 20 */
Simon Cooksey 0:fb7af294d5d9 21
Simon Cooksey 0:fb7af294d5d9 22 #if !defined(MBEDTLS_CONFIG_FILE)
Simon Cooksey 0:fb7af294d5d9 23 #include "mbedtls/config.h"
Simon Cooksey 0:fb7af294d5d9 24 #else
Simon Cooksey 0:fb7af294d5d9 25 #include MBEDTLS_CONFIG_FILE
Simon Cooksey 0:fb7af294d5d9 26 #endif
Simon Cooksey 0:fb7af294d5d9 27
Simon Cooksey 0:fb7af294d5d9 28 #if defined(MBEDTLS_SSL_TICKET_C)
Simon Cooksey 0:fb7af294d5d9 29
Simon Cooksey 0:fb7af294d5d9 30 #if defined(MBEDTLS_PLATFORM_C)
Simon Cooksey 0:fb7af294d5d9 31 #include "mbedtls/platform.h"
Simon Cooksey 0:fb7af294d5d9 32 #else
Simon Cooksey 0:fb7af294d5d9 33 #include <stdlib.h>
Simon Cooksey 0:fb7af294d5d9 34 #define mbedtls_calloc calloc
Simon Cooksey 0:fb7af294d5d9 35 #define mbedtls_free free
Simon Cooksey 0:fb7af294d5d9 36 #endif
Simon Cooksey 0:fb7af294d5d9 37
Simon Cooksey 0:fb7af294d5d9 38 #include "mbedtls/ssl_ticket.h"
Simon Cooksey 0:fb7af294d5d9 39
Simon Cooksey 0:fb7af294d5d9 40 #include <string.h>
Simon Cooksey 0:fb7af294d5d9 41
Simon Cooksey 0:fb7af294d5d9 42 /* Implementation that should never be optimized out by the compiler */
Simon Cooksey 0:fb7af294d5d9 43 static void mbedtls_zeroize( void *v, size_t n ) {
Simon Cooksey 0:fb7af294d5d9 44 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
Simon Cooksey 0:fb7af294d5d9 45 }
Simon Cooksey 0:fb7af294d5d9 46
Simon Cooksey 0:fb7af294d5d9 47 /*
Simon Cooksey 0:fb7af294d5d9 48 * Initialze context
Simon Cooksey 0:fb7af294d5d9 49 */
Simon Cooksey 0:fb7af294d5d9 50 void mbedtls_ssl_ticket_init( mbedtls_ssl_ticket_context *ctx )
Simon Cooksey 0:fb7af294d5d9 51 {
Simon Cooksey 0:fb7af294d5d9 52 memset( ctx, 0, sizeof( mbedtls_ssl_ticket_context ) );
Simon Cooksey 0:fb7af294d5d9 53
Simon Cooksey 0:fb7af294d5d9 54 #if defined(MBEDTLS_THREADING_C)
Simon Cooksey 0:fb7af294d5d9 55 mbedtls_mutex_init( &ctx->mutex );
Simon Cooksey 0:fb7af294d5d9 56 #endif
Simon Cooksey 0:fb7af294d5d9 57 }
Simon Cooksey 0:fb7af294d5d9 58
Simon Cooksey 0:fb7af294d5d9 59 #define MAX_KEY_BYTES 32 /* 256 bits */
Simon Cooksey 0:fb7af294d5d9 60
Simon Cooksey 0:fb7af294d5d9 61 /*
Simon Cooksey 0:fb7af294d5d9 62 * Generate/update a key
Simon Cooksey 0:fb7af294d5d9 63 */
Simon Cooksey 0:fb7af294d5d9 64 static int ssl_ticket_gen_key( mbedtls_ssl_ticket_context *ctx,
Simon Cooksey 0:fb7af294d5d9 65 unsigned char index )
Simon Cooksey 0:fb7af294d5d9 66 {
Simon Cooksey 0:fb7af294d5d9 67 int ret;
Simon Cooksey 0:fb7af294d5d9 68 unsigned char buf[MAX_KEY_BYTES];
Simon Cooksey 0:fb7af294d5d9 69 mbedtls_ssl_ticket_key *key = ctx->keys + index;
Simon Cooksey 0:fb7af294d5d9 70
Simon Cooksey 0:fb7af294d5d9 71 #if defined(MBEDTLS_HAVE_TIME)
Simon Cooksey 0:fb7af294d5d9 72 key->generation_time = (uint32_t) mbedtls_time( NULL );
Simon Cooksey 0:fb7af294d5d9 73 #endif
Simon Cooksey 0:fb7af294d5d9 74
Simon Cooksey 0:fb7af294d5d9 75 if( ( ret = ctx->f_rng( ctx->p_rng, key->name, sizeof( key->name ) ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 76 return( ret );
Simon Cooksey 0:fb7af294d5d9 77
Simon Cooksey 0:fb7af294d5d9 78 if( ( ret = ctx->f_rng( ctx->p_rng, buf, sizeof( buf ) ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 79 return( ret );
Simon Cooksey 0:fb7af294d5d9 80
Simon Cooksey 0:fb7af294d5d9 81 /* With GCM and CCM, same context can encrypt & decrypt */
Simon Cooksey 0:fb7af294d5d9 82 ret = mbedtls_cipher_setkey( &key->ctx, buf,
Simon Cooksey 0:fb7af294d5d9 83 mbedtls_cipher_get_key_bitlen( &key->ctx ),
Simon Cooksey 0:fb7af294d5d9 84 MBEDTLS_ENCRYPT );
Simon Cooksey 0:fb7af294d5d9 85
Simon Cooksey 0:fb7af294d5d9 86 mbedtls_zeroize( buf, sizeof( buf ) );
Simon Cooksey 0:fb7af294d5d9 87
Simon Cooksey 0:fb7af294d5d9 88 return( ret );
Simon Cooksey 0:fb7af294d5d9 89 }
Simon Cooksey 0:fb7af294d5d9 90
Simon Cooksey 0:fb7af294d5d9 91 /*
Simon Cooksey 0:fb7af294d5d9 92 * Rotate/generate keys if necessary
Simon Cooksey 0:fb7af294d5d9 93 */
Simon Cooksey 0:fb7af294d5d9 94 static int ssl_ticket_update_keys( mbedtls_ssl_ticket_context *ctx )
Simon Cooksey 0:fb7af294d5d9 95 {
Simon Cooksey 0:fb7af294d5d9 96 #if !defined(MBEDTLS_HAVE_TIME)
Simon Cooksey 0:fb7af294d5d9 97 ((void) ctx);
Simon Cooksey 0:fb7af294d5d9 98 #else
Simon Cooksey 0:fb7af294d5d9 99 if( ctx->ticket_lifetime != 0 )
Simon Cooksey 0:fb7af294d5d9 100 {
Simon Cooksey 0:fb7af294d5d9 101 uint32_t current_time = (uint32_t) mbedtls_time( NULL );
Simon Cooksey 0:fb7af294d5d9 102 uint32_t key_time = ctx->keys[ctx->active].generation_time;
Simon Cooksey 0:fb7af294d5d9 103
Simon Cooksey 0:fb7af294d5d9 104 if( current_time > key_time &&
Simon Cooksey 0:fb7af294d5d9 105 current_time - key_time < ctx->ticket_lifetime )
Simon Cooksey 0:fb7af294d5d9 106 {
Simon Cooksey 0:fb7af294d5d9 107 return( 0 );
Simon Cooksey 0:fb7af294d5d9 108 }
Simon Cooksey 0:fb7af294d5d9 109
Simon Cooksey 0:fb7af294d5d9 110 ctx->active = 1 - ctx->active;
Simon Cooksey 0:fb7af294d5d9 111
Simon Cooksey 0:fb7af294d5d9 112 return( ssl_ticket_gen_key( ctx, ctx->active ) );
Simon Cooksey 0:fb7af294d5d9 113 }
Simon Cooksey 0:fb7af294d5d9 114 else
Simon Cooksey 0:fb7af294d5d9 115 #endif /* MBEDTLS_HAVE_TIME */
Simon Cooksey 0:fb7af294d5d9 116 return( 0 );
Simon Cooksey 0:fb7af294d5d9 117 }
Simon Cooksey 0:fb7af294d5d9 118
Simon Cooksey 0:fb7af294d5d9 119 /*
Simon Cooksey 0:fb7af294d5d9 120 * Setup context for actual use
Simon Cooksey 0:fb7af294d5d9 121 */
Simon Cooksey 0:fb7af294d5d9 122 int mbedtls_ssl_ticket_setup( mbedtls_ssl_ticket_context *ctx,
Simon Cooksey 0:fb7af294d5d9 123 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
Simon Cooksey 0:fb7af294d5d9 124 mbedtls_cipher_type_t cipher,
Simon Cooksey 0:fb7af294d5d9 125 uint32_t lifetime )
Simon Cooksey 0:fb7af294d5d9 126 {
Simon Cooksey 0:fb7af294d5d9 127 int ret;
Simon Cooksey 0:fb7af294d5d9 128 const mbedtls_cipher_info_t *cipher_info;
Simon Cooksey 0:fb7af294d5d9 129
Simon Cooksey 0:fb7af294d5d9 130 ctx->f_rng = f_rng;
Simon Cooksey 0:fb7af294d5d9 131 ctx->p_rng = p_rng;
Simon Cooksey 0:fb7af294d5d9 132
Simon Cooksey 0:fb7af294d5d9 133 ctx->ticket_lifetime = lifetime;
Simon Cooksey 0:fb7af294d5d9 134
Simon Cooksey 0:fb7af294d5d9 135 cipher_info = mbedtls_cipher_info_from_type( cipher);
Simon Cooksey 0:fb7af294d5d9 136 if( cipher_info == NULL )
Simon Cooksey 0:fb7af294d5d9 137 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 138
Simon Cooksey 0:fb7af294d5d9 139 if( cipher_info->mode != MBEDTLS_MODE_GCM &&
Simon Cooksey 0:fb7af294d5d9 140 cipher_info->mode != MBEDTLS_MODE_CCM )
Simon Cooksey 0:fb7af294d5d9 141 {
Simon Cooksey 0:fb7af294d5d9 142 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 143 }
Simon Cooksey 0:fb7af294d5d9 144
Simon Cooksey 0:fb7af294d5d9 145 if( cipher_info->key_bitlen > 8 * MAX_KEY_BYTES )
Simon Cooksey 0:fb7af294d5d9 146 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 147
Simon Cooksey 0:fb7af294d5d9 148 if( ( ret = mbedtls_cipher_setup( &ctx->keys[0].ctx, cipher_info ) ) != 0 ||
Simon Cooksey 0:fb7af294d5d9 149 ( ret = mbedtls_cipher_setup( &ctx->keys[1].ctx, cipher_info ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 150 {
Simon Cooksey 0:fb7af294d5d9 151 return( ret );
Simon Cooksey 0:fb7af294d5d9 152 }
Simon Cooksey 0:fb7af294d5d9 153
Simon Cooksey 0:fb7af294d5d9 154 if( ( ret = ssl_ticket_gen_key( ctx, 0 ) ) != 0 ||
Simon Cooksey 0:fb7af294d5d9 155 ( ret = ssl_ticket_gen_key( ctx, 1 ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 156 {
Simon Cooksey 0:fb7af294d5d9 157 return( ret );
Simon Cooksey 0:fb7af294d5d9 158 }
Simon Cooksey 0:fb7af294d5d9 159
Simon Cooksey 0:fb7af294d5d9 160 return( 0 );
Simon Cooksey 0:fb7af294d5d9 161 }
Simon Cooksey 0:fb7af294d5d9 162
Simon Cooksey 0:fb7af294d5d9 163 /*
Simon Cooksey 0:fb7af294d5d9 164 * Serialize a session in the following format:
Simon Cooksey 0:fb7af294d5d9 165 * 0 . n-1 session structure, n = sizeof(mbedtls_ssl_session)
Simon Cooksey 0:fb7af294d5d9 166 * n . n+2 peer_cert length = m (0 if no certificate)
Simon Cooksey 0:fb7af294d5d9 167 * n+3 . n+2+m peer cert ASN.1
Simon Cooksey 0:fb7af294d5d9 168 */
Simon Cooksey 0:fb7af294d5d9 169 static int ssl_save_session( const mbedtls_ssl_session *session,
Simon Cooksey 0:fb7af294d5d9 170 unsigned char *buf, size_t buf_len,
Simon Cooksey 0:fb7af294d5d9 171 size_t *olen )
Simon Cooksey 0:fb7af294d5d9 172 {
Simon Cooksey 0:fb7af294d5d9 173 unsigned char *p = buf;
Simon Cooksey 0:fb7af294d5d9 174 size_t left = buf_len;
Simon Cooksey 0:fb7af294d5d9 175 #if defined(MBEDTLS_X509_CRT_PARSE_C)
Simon Cooksey 0:fb7af294d5d9 176 size_t cert_len;
Simon Cooksey 0:fb7af294d5d9 177 #endif /* MBEDTLS_X509_CRT_PARSE_C */
Simon Cooksey 0:fb7af294d5d9 178
Simon Cooksey 0:fb7af294d5d9 179 if( left < sizeof( mbedtls_ssl_session ) )
Simon Cooksey 0:fb7af294d5d9 180 return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
Simon Cooksey 0:fb7af294d5d9 181
Simon Cooksey 0:fb7af294d5d9 182 memcpy( p, session, sizeof( mbedtls_ssl_session ) );
Simon Cooksey 0:fb7af294d5d9 183 p += sizeof( mbedtls_ssl_session );
Simon Cooksey 0:fb7af294d5d9 184 left -= sizeof( mbedtls_ssl_session );
Simon Cooksey 0:fb7af294d5d9 185
Simon Cooksey 0:fb7af294d5d9 186 #if defined(MBEDTLS_X509_CRT_PARSE_C)
Simon Cooksey 0:fb7af294d5d9 187 if( session->peer_cert == NULL )
Simon Cooksey 0:fb7af294d5d9 188 cert_len = 0;
Simon Cooksey 0:fb7af294d5d9 189 else
Simon Cooksey 0:fb7af294d5d9 190 cert_len = session->peer_cert->raw.len;
Simon Cooksey 0:fb7af294d5d9 191
Simon Cooksey 0:fb7af294d5d9 192 if( left < 3 + cert_len )
Simon Cooksey 0:fb7af294d5d9 193 return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
Simon Cooksey 0:fb7af294d5d9 194
Simon Cooksey 0:fb7af294d5d9 195 *p++ = (unsigned char)( cert_len >> 16 & 0xFF );
Simon Cooksey 0:fb7af294d5d9 196 *p++ = (unsigned char)( cert_len >> 8 & 0xFF );
Simon Cooksey 0:fb7af294d5d9 197 *p++ = (unsigned char)( cert_len & 0xFF );
Simon Cooksey 0:fb7af294d5d9 198
Simon Cooksey 0:fb7af294d5d9 199 if( session->peer_cert != NULL )
Simon Cooksey 0:fb7af294d5d9 200 memcpy( p, session->peer_cert->raw.p, cert_len );
Simon Cooksey 0:fb7af294d5d9 201
Simon Cooksey 0:fb7af294d5d9 202 p += cert_len;
Simon Cooksey 0:fb7af294d5d9 203 #endif /* MBEDTLS_X509_CRT_PARSE_C */
Simon Cooksey 0:fb7af294d5d9 204
Simon Cooksey 0:fb7af294d5d9 205 *olen = p - buf;
Simon Cooksey 0:fb7af294d5d9 206
Simon Cooksey 0:fb7af294d5d9 207 return( 0 );
Simon Cooksey 0:fb7af294d5d9 208 }
Simon Cooksey 0:fb7af294d5d9 209
Simon Cooksey 0:fb7af294d5d9 210 /*
Simon Cooksey 0:fb7af294d5d9 211 * Unserialise session, see ssl_save_session()
Simon Cooksey 0:fb7af294d5d9 212 */
Simon Cooksey 0:fb7af294d5d9 213 static int ssl_load_session( mbedtls_ssl_session *session,
Simon Cooksey 0:fb7af294d5d9 214 const unsigned char *buf, size_t len )
Simon Cooksey 0:fb7af294d5d9 215 {
Simon Cooksey 0:fb7af294d5d9 216 const unsigned char *p = buf;
Simon Cooksey 0:fb7af294d5d9 217 const unsigned char * const end = buf + len;
Simon Cooksey 0:fb7af294d5d9 218 #if defined(MBEDTLS_X509_CRT_PARSE_C)
Simon Cooksey 0:fb7af294d5d9 219 size_t cert_len;
Simon Cooksey 0:fb7af294d5d9 220 #endif /* MBEDTLS_X509_CRT_PARSE_C */
Simon Cooksey 0:fb7af294d5d9 221
Simon Cooksey 0:fb7af294d5d9 222 if( p + sizeof( mbedtls_ssl_session ) > end )
Simon Cooksey 0:fb7af294d5d9 223 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 224
Simon Cooksey 0:fb7af294d5d9 225 memcpy( session, p, sizeof( mbedtls_ssl_session ) );
Simon Cooksey 0:fb7af294d5d9 226 p += sizeof( mbedtls_ssl_session );
Simon Cooksey 0:fb7af294d5d9 227
Simon Cooksey 0:fb7af294d5d9 228 #if defined(MBEDTLS_X509_CRT_PARSE_C)
Simon Cooksey 0:fb7af294d5d9 229 if( p + 3 > end )
Simon Cooksey 0:fb7af294d5d9 230 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 231
Simon Cooksey 0:fb7af294d5d9 232 cert_len = ( p[0] << 16 ) | ( p[1] << 8 ) | p[2];
Simon Cooksey 0:fb7af294d5d9 233 p += 3;
Simon Cooksey 0:fb7af294d5d9 234
Simon Cooksey 0:fb7af294d5d9 235 if( cert_len == 0 )
Simon Cooksey 0:fb7af294d5d9 236 {
Simon Cooksey 0:fb7af294d5d9 237 session->peer_cert = NULL;
Simon Cooksey 0:fb7af294d5d9 238 }
Simon Cooksey 0:fb7af294d5d9 239 else
Simon Cooksey 0:fb7af294d5d9 240 {
Simon Cooksey 0:fb7af294d5d9 241 int ret;
Simon Cooksey 0:fb7af294d5d9 242
Simon Cooksey 0:fb7af294d5d9 243 if( p + cert_len > end )
Simon Cooksey 0:fb7af294d5d9 244 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 245
Simon Cooksey 0:fb7af294d5d9 246 session->peer_cert = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
Simon Cooksey 0:fb7af294d5d9 247
Simon Cooksey 0:fb7af294d5d9 248 if( session->peer_cert == NULL )
Simon Cooksey 0:fb7af294d5d9 249 return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
Simon Cooksey 0:fb7af294d5d9 250
Simon Cooksey 0:fb7af294d5d9 251 mbedtls_x509_crt_init( session->peer_cert );
Simon Cooksey 0:fb7af294d5d9 252
Simon Cooksey 0:fb7af294d5d9 253 if( ( ret = mbedtls_x509_crt_parse_der( session->peer_cert,
Simon Cooksey 0:fb7af294d5d9 254 p, cert_len ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 255 {
Simon Cooksey 0:fb7af294d5d9 256 mbedtls_x509_crt_free( session->peer_cert );
Simon Cooksey 0:fb7af294d5d9 257 mbedtls_free( session->peer_cert );
Simon Cooksey 0:fb7af294d5d9 258 session->peer_cert = NULL;
Simon Cooksey 0:fb7af294d5d9 259 return( ret );
Simon Cooksey 0:fb7af294d5d9 260 }
Simon Cooksey 0:fb7af294d5d9 261
Simon Cooksey 0:fb7af294d5d9 262 p += cert_len;
Simon Cooksey 0:fb7af294d5d9 263 }
Simon Cooksey 0:fb7af294d5d9 264 #endif /* MBEDTLS_X509_CRT_PARSE_C */
Simon Cooksey 0:fb7af294d5d9 265
Simon Cooksey 0:fb7af294d5d9 266 if( p != end )
Simon Cooksey 0:fb7af294d5d9 267 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 268
Simon Cooksey 0:fb7af294d5d9 269 return( 0 );
Simon Cooksey 0:fb7af294d5d9 270 }
Simon Cooksey 0:fb7af294d5d9 271
Simon Cooksey 0:fb7af294d5d9 272 /*
Simon Cooksey 0:fb7af294d5d9 273 * Create session ticket, with the following structure:
Simon Cooksey 0:fb7af294d5d9 274 *
Simon Cooksey 0:fb7af294d5d9 275 * struct {
Simon Cooksey 0:fb7af294d5d9 276 * opaque key_name[4];
Simon Cooksey 0:fb7af294d5d9 277 * opaque iv[12];
Simon Cooksey 0:fb7af294d5d9 278 * opaque encrypted_state<0..2^16-1>;
Simon Cooksey 0:fb7af294d5d9 279 * opaque tag[16];
Simon Cooksey 0:fb7af294d5d9 280 * } ticket;
Simon Cooksey 0:fb7af294d5d9 281 *
Simon Cooksey 0:fb7af294d5d9 282 * The key_name, iv, and length of encrypted_state are the additional
Simon Cooksey 0:fb7af294d5d9 283 * authenticated data.
Simon Cooksey 0:fb7af294d5d9 284 */
Simon Cooksey 0:fb7af294d5d9 285 int mbedtls_ssl_ticket_write( void *p_ticket,
Simon Cooksey 0:fb7af294d5d9 286 const mbedtls_ssl_session *session,
Simon Cooksey 0:fb7af294d5d9 287 unsigned char *start,
Simon Cooksey 0:fb7af294d5d9 288 const unsigned char *end,
Simon Cooksey 0:fb7af294d5d9 289 size_t *tlen,
Simon Cooksey 0:fb7af294d5d9 290 uint32_t *ticket_lifetime )
Simon Cooksey 0:fb7af294d5d9 291 {
Simon Cooksey 0:fb7af294d5d9 292 int ret;
Simon Cooksey 0:fb7af294d5d9 293 mbedtls_ssl_ticket_context *ctx = p_ticket;
Simon Cooksey 0:fb7af294d5d9 294 mbedtls_ssl_ticket_key *key;
Simon Cooksey 0:fb7af294d5d9 295 unsigned char *key_name = start;
Simon Cooksey 0:fb7af294d5d9 296 unsigned char *iv = start + 4;
Simon Cooksey 0:fb7af294d5d9 297 unsigned char *state_len_bytes = iv + 12;
Simon Cooksey 0:fb7af294d5d9 298 unsigned char *state = state_len_bytes + 2;
Simon Cooksey 0:fb7af294d5d9 299 unsigned char *tag;
Simon Cooksey 0:fb7af294d5d9 300 size_t clear_len, ciph_len;
Simon Cooksey 0:fb7af294d5d9 301
Simon Cooksey 0:fb7af294d5d9 302 *tlen = 0;
Simon Cooksey 0:fb7af294d5d9 303
Simon Cooksey 0:fb7af294d5d9 304 if( ctx == NULL || ctx->f_rng == NULL )
Simon Cooksey 0:fb7af294d5d9 305 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 306
Simon Cooksey 0:fb7af294d5d9 307 /* We need at least 4 bytes for key_name, 12 for IV, 2 for len 16 for tag,
Simon Cooksey 0:fb7af294d5d9 308 * in addition to session itself, that will be checked when writing it. */
Simon Cooksey 0:fb7af294d5d9 309 if( end - start < 4 + 12 + 2 + 16 )
Simon Cooksey 0:fb7af294d5d9 310 return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
Simon Cooksey 0:fb7af294d5d9 311
Simon Cooksey 0:fb7af294d5d9 312 #if defined(MBEDTLS_THREADING_C)
Simon Cooksey 0:fb7af294d5d9 313 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 314 return( ret );
Simon Cooksey 0:fb7af294d5d9 315 #endif
Simon Cooksey 0:fb7af294d5d9 316
Simon Cooksey 0:fb7af294d5d9 317 if( ( ret = ssl_ticket_update_keys( ctx ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 318 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 319
Simon Cooksey 0:fb7af294d5d9 320 key = &ctx->keys[ctx->active];
Simon Cooksey 0:fb7af294d5d9 321
Simon Cooksey 0:fb7af294d5d9 322 *ticket_lifetime = ctx->ticket_lifetime;
Simon Cooksey 0:fb7af294d5d9 323
Simon Cooksey 0:fb7af294d5d9 324 memcpy( key_name, key->name, 4 );
Simon Cooksey 0:fb7af294d5d9 325
Simon Cooksey 0:fb7af294d5d9 326 if( ( ret = ctx->f_rng( ctx->p_rng, iv, 12 ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 327 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 328
Simon Cooksey 0:fb7af294d5d9 329 /* Dump session state */
Simon Cooksey 0:fb7af294d5d9 330 if( ( ret = ssl_save_session( session,
Simon Cooksey 0:fb7af294d5d9 331 state, end - state, &clear_len ) ) != 0 ||
Simon Cooksey 0:fb7af294d5d9 332 (unsigned long) clear_len > 65535 )
Simon Cooksey 0:fb7af294d5d9 333 {
Simon Cooksey 0:fb7af294d5d9 334 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 335 }
Simon Cooksey 0:fb7af294d5d9 336 state_len_bytes[0] = ( clear_len >> 8 ) & 0xff;
Simon Cooksey 0:fb7af294d5d9 337 state_len_bytes[1] = ( clear_len ) & 0xff;
Simon Cooksey 0:fb7af294d5d9 338
Simon Cooksey 0:fb7af294d5d9 339 /* Encrypt and authenticate */
Simon Cooksey 0:fb7af294d5d9 340 tag = state + clear_len;
Simon Cooksey 0:fb7af294d5d9 341 if( ( ret = mbedtls_cipher_auth_encrypt( &key->ctx,
Simon Cooksey 0:fb7af294d5d9 342 iv, 12, key_name, 4 + 12 + 2,
Simon Cooksey 0:fb7af294d5d9 343 state, clear_len, state, &ciph_len, tag, 16 ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 344 {
Simon Cooksey 0:fb7af294d5d9 345 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 346 }
Simon Cooksey 0:fb7af294d5d9 347 if( ciph_len != clear_len )
Simon Cooksey 0:fb7af294d5d9 348 {
Simon Cooksey 0:fb7af294d5d9 349 ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
Simon Cooksey 0:fb7af294d5d9 350 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 351 }
Simon Cooksey 0:fb7af294d5d9 352
Simon Cooksey 0:fb7af294d5d9 353 *tlen = 4 + 12 + 2 + 16 + ciph_len;
Simon Cooksey 0:fb7af294d5d9 354
Simon Cooksey 0:fb7af294d5d9 355 cleanup:
Simon Cooksey 0:fb7af294d5d9 356 #if defined(MBEDTLS_THREADING_C)
Simon Cooksey 0:fb7af294d5d9 357 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
Simon Cooksey 0:fb7af294d5d9 358 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
Simon Cooksey 0:fb7af294d5d9 359 #endif
Simon Cooksey 0:fb7af294d5d9 360
Simon Cooksey 0:fb7af294d5d9 361 return( ret );
Simon Cooksey 0:fb7af294d5d9 362 }
Simon Cooksey 0:fb7af294d5d9 363
Simon Cooksey 0:fb7af294d5d9 364 /*
Simon Cooksey 0:fb7af294d5d9 365 * Select key based on name
Simon Cooksey 0:fb7af294d5d9 366 */
Simon Cooksey 0:fb7af294d5d9 367 static mbedtls_ssl_ticket_key *ssl_ticket_select_key(
Simon Cooksey 0:fb7af294d5d9 368 mbedtls_ssl_ticket_context *ctx,
Simon Cooksey 0:fb7af294d5d9 369 const unsigned char name[4] )
Simon Cooksey 0:fb7af294d5d9 370 {
Simon Cooksey 0:fb7af294d5d9 371 unsigned char i;
Simon Cooksey 0:fb7af294d5d9 372
Simon Cooksey 0:fb7af294d5d9 373 for( i = 0; i < sizeof( ctx->keys ) / sizeof( *ctx->keys ); i++ )
Simon Cooksey 0:fb7af294d5d9 374 if( memcmp( name, ctx->keys[i].name, 4 ) == 0 )
Simon Cooksey 0:fb7af294d5d9 375 return( &ctx->keys[i] );
Simon Cooksey 0:fb7af294d5d9 376
Simon Cooksey 0:fb7af294d5d9 377 return( NULL );
Simon Cooksey 0:fb7af294d5d9 378 }
Simon Cooksey 0:fb7af294d5d9 379
Simon Cooksey 0:fb7af294d5d9 380 /*
Simon Cooksey 0:fb7af294d5d9 381 * Load session ticket (see mbedtls_ssl_ticket_write for structure)
Simon Cooksey 0:fb7af294d5d9 382 */
Simon Cooksey 0:fb7af294d5d9 383 int mbedtls_ssl_ticket_parse( void *p_ticket,
Simon Cooksey 0:fb7af294d5d9 384 mbedtls_ssl_session *session,
Simon Cooksey 0:fb7af294d5d9 385 unsigned char *buf,
Simon Cooksey 0:fb7af294d5d9 386 size_t len )
Simon Cooksey 0:fb7af294d5d9 387 {
Simon Cooksey 0:fb7af294d5d9 388 int ret;
Simon Cooksey 0:fb7af294d5d9 389 mbedtls_ssl_ticket_context *ctx = p_ticket;
Simon Cooksey 0:fb7af294d5d9 390 mbedtls_ssl_ticket_key *key;
Simon Cooksey 0:fb7af294d5d9 391 unsigned char *key_name = buf;
Simon Cooksey 0:fb7af294d5d9 392 unsigned char *iv = buf + 4;
Simon Cooksey 0:fb7af294d5d9 393 unsigned char *enc_len_p = iv + 12;
Simon Cooksey 0:fb7af294d5d9 394 unsigned char *ticket = enc_len_p + 2;
Simon Cooksey 0:fb7af294d5d9 395 unsigned char *tag;
Simon Cooksey 0:fb7af294d5d9 396 size_t enc_len, clear_len;
Simon Cooksey 0:fb7af294d5d9 397
Simon Cooksey 0:fb7af294d5d9 398 if( ctx == NULL || ctx->f_rng == NULL )
Simon Cooksey 0:fb7af294d5d9 399 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 400
Simon Cooksey 0:fb7af294d5d9 401 /* See mbedtls_ssl_ticket_write() */
Simon Cooksey 0:fb7af294d5d9 402 if( len < 4 + 12 + 2 + 16 )
Simon Cooksey 0:fb7af294d5d9 403 return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
Simon Cooksey 0:fb7af294d5d9 404
Simon Cooksey 0:fb7af294d5d9 405 #if defined(MBEDTLS_THREADING_C)
Simon Cooksey 0:fb7af294d5d9 406 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 407 return( ret );
Simon Cooksey 0:fb7af294d5d9 408 #endif
Simon Cooksey 0:fb7af294d5d9 409
Simon Cooksey 0:fb7af294d5d9 410 if( ( ret = ssl_ticket_update_keys( ctx ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 411 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 412
Simon Cooksey 0:fb7af294d5d9 413 enc_len = ( enc_len_p[0] << 8 ) | enc_len_p[1];
Simon Cooksey 0:fb7af294d5d9 414 tag = ticket + enc_len;
Simon Cooksey 0:fb7af294d5d9 415
Simon Cooksey 0:fb7af294d5d9 416 if( len != 4 + 12 + 2 + enc_len + 16 )
Simon Cooksey 0:fb7af294d5d9 417 {
Simon Cooksey 0:fb7af294d5d9 418 ret = MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
Simon Cooksey 0:fb7af294d5d9 419 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 420 }
Simon Cooksey 0:fb7af294d5d9 421
Simon Cooksey 0:fb7af294d5d9 422 /* Select key */
Simon Cooksey 0:fb7af294d5d9 423 if( ( key = ssl_ticket_select_key( ctx, key_name ) ) == NULL )
Simon Cooksey 0:fb7af294d5d9 424 {
Simon Cooksey 0:fb7af294d5d9 425 /* We can't know for sure but this is a likely option unless we're
Simon Cooksey 0:fb7af294d5d9 426 * under attack - this is only informative anyway */
Simon Cooksey 0:fb7af294d5d9 427 ret = MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED;
Simon Cooksey 0:fb7af294d5d9 428 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 429 }
Simon Cooksey 0:fb7af294d5d9 430
Simon Cooksey 0:fb7af294d5d9 431 /* Decrypt and authenticate */
Simon Cooksey 0:fb7af294d5d9 432 if( ( ret = mbedtls_cipher_auth_decrypt( &key->ctx, iv, 12,
Simon Cooksey 0:fb7af294d5d9 433 key_name, 4 + 12 + 2, ticket, enc_len,
Simon Cooksey 0:fb7af294d5d9 434 ticket, &clear_len, tag, 16 ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 435 {
Simon Cooksey 0:fb7af294d5d9 436 if( ret == MBEDTLS_ERR_CIPHER_AUTH_FAILED )
Simon Cooksey 0:fb7af294d5d9 437 ret = MBEDTLS_ERR_SSL_INVALID_MAC;
Simon Cooksey 0:fb7af294d5d9 438
Simon Cooksey 0:fb7af294d5d9 439 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 440 }
Simon Cooksey 0:fb7af294d5d9 441 if( clear_len != enc_len )
Simon Cooksey 0:fb7af294d5d9 442 {
Simon Cooksey 0:fb7af294d5d9 443 ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
Simon Cooksey 0:fb7af294d5d9 444 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 445 }
Simon Cooksey 0:fb7af294d5d9 446
Simon Cooksey 0:fb7af294d5d9 447 /* Actually load session */
Simon Cooksey 0:fb7af294d5d9 448 if( ( ret = ssl_load_session( session, ticket, clear_len ) ) != 0 )
Simon Cooksey 0:fb7af294d5d9 449 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 450
Simon Cooksey 0:fb7af294d5d9 451 #if defined(MBEDTLS_HAVE_TIME)
Simon Cooksey 0:fb7af294d5d9 452 {
Simon Cooksey 0:fb7af294d5d9 453 /* Check for expiration */
Simon Cooksey 0:fb7af294d5d9 454 mbedtls_time_t current_time = mbedtls_time( NULL );
Simon Cooksey 0:fb7af294d5d9 455
Simon Cooksey 0:fb7af294d5d9 456 if( current_time < session->start ||
Simon Cooksey 0:fb7af294d5d9 457 (uint32_t)( current_time - session->start ) > ctx->ticket_lifetime )
Simon Cooksey 0:fb7af294d5d9 458 {
Simon Cooksey 0:fb7af294d5d9 459 ret = MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED;
Simon Cooksey 0:fb7af294d5d9 460 goto cleanup;
Simon Cooksey 0:fb7af294d5d9 461 }
Simon Cooksey 0:fb7af294d5d9 462 }
Simon Cooksey 0:fb7af294d5d9 463 #endif
Simon Cooksey 0:fb7af294d5d9 464
Simon Cooksey 0:fb7af294d5d9 465 cleanup:
Simon Cooksey 0:fb7af294d5d9 466 #if defined(MBEDTLS_THREADING_C)
Simon Cooksey 0:fb7af294d5d9 467 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
Simon Cooksey 0:fb7af294d5d9 468 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
Simon Cooksey 0:fb7af294d5d9 469 #endif
Simon Cooksey 0:fb7af294d5d9 470
Simon Cooksey 0:fb7af294d5d9 471 return( ret );
Simon Cooksey 0:fb7af294d5d9 472 }
Simon Cooksey 0:fb7af294d5d9 473
Simon Cooksey 0:fb7af294d5d9 474 /*
Simon Cooksey 0:fb7af294d5d9 475 * Free context
Simon Cooksey 0:fb7af294d5d9 476 */
Simon Cooksey 0:fb7af294d5d9 477 void mbedtls_ssl_ticket_free( mbedtls_ssl_ticket_context *ctx )
Simon Cooksey 0:fb7af294d5d9 478 {
Simon Cooksey 0:fb7af294d5d9 479 mbedtls_cipher_free( &ctx->keys[0].ctx );
Simon Cooksey 0:fb7af294d5d9 480 mbedtls_cipher_free( &ctx->keys[1].ctx );
Simon Cooksey 0:fb7af294d5d9 481
Simon Cooksey 0:fb7af294d5d9 482 #if defined(MBEDTLS_THREADING_C)
Simon Cooksey 0:fb7af294d5d9 483 mbedtls_mutex_free( &ctx->mutex );
Simon Cooksey 0:fb7af294d5d9 484 #endif
Simon Cooksey 0:fb7af294d5d9 485
Simon Cooksey 0:fb7af294d5d9 486 mbedtls_zeroize( ctx, sizeof( mbedtls_ssl_ticket_context ) );
Simon Cooksey 0:fb7af294d5d9 487 }
Simon Cooksey 0:fb7af294d5d9 488
Simon Cooksey 0:fb7af294d5d9 489 #endif /* MBEDTLS_SSL_TICKET_C */