/*
* DTLS implementation written by Nagendra Modadugu
* (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
*/
/* ====================================================================
* Copyright (c) 1999-2005 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com). */
#include <openssl_grpc/ssl.h>
#include <assert.h>
#include <limits.h>
#include <string.h>
#include <openssl_grpc/err.h>
#include <openssl_grpc/mem.h>
#include <openssl_grpc/nid.h>
#include "../crypto/internal.h"
#include "internal.h"
BSSL_NAMESPACE_BEGIN
// DTLS1_MTU_TIMEOUTS is the maximum number of timeouts to expire
// before starting to decrease the MTU.
#define DTLS1_MTU_TIMEOUTS 2
// DTLS1_MAX_TIMEOUTS is the maximum number of timeouts to expire
// before failing the DTLS handshake.
#define DTLS1_MAX_TIMEOUTS 12
DTLS1_STATE::DTLS1_STATE()
: has_change_cipher_spec(false),
outgoing_messages_complete(false),
flight_has_reply(false) {}
DTLS1_STATE::~DTLS1_STATE() {}
bool dtls1_new(SSL *ssl) {
if (!tls_new(ssl)) {
return false;
}
UniquePtr<DTLS1_STATE> d1 = MakeUnique<DTLS1_STATE>();
if (!d1) {
tls_free(ssl);
return false;
}
ssl->d1 = d1.release();
// Set the version to the highest supported version.
//
// TODO(davidben): Move this field into |s3|, have it store the normalized
// protocol version, and implement this pre-negotiation quirk in |SSL_version|
// at the API boundary rather than in internal state.
ssl->version = DTLS1_2_VERSION;
return true;
}
void dtls1_free(SSL *ssl) {
tls_free(ssl);
if (ssl == NULL) {
return;
}
Delete(ssl->d1);
ssl->d1 = NULL;
}
void dtls1_start_timer(SSL *ssl) {
// If timer is not set, initialize duration (by default, 1 second)
if (ssl->d1->next_timeout.tv_sec == 0 && ssl->d1->next_timeout.tv_usec == 0) {
ssl->d1->timeout_duration_ms = ssl->initial_timeout_duration_ms;
}
// Set timeout to current time
ssl_get_current_time(ssl, &ssl->d1->next_timeout);
// Add duration to current time
ssl->d1->next_timeout.tv_sec += ssl->d1->timeout_duration_ms / 1000;
ssl->d1->next_timeout.tv_usec += (ssl->d1->timeout_duration_ms % 1000) * 1000;
if (ssl->d1->next_timeout.tv_usec >= 1000000) {
ssl->d1->next_timeout.tv_sec++;
ssl->d1->next_timeout.tv_usec -= 1000000;
}
}
bool dtls1_is_timer_expired(SSL *ssl) {
struct timeval timeleft;
// Get time left until timeout, return false if no timer running
if (!DTLSv1_get_timeout(ssl, &timeleft)) {
return false;
}
// Return false if timer is not expired yet
if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0) {
return false;
}
// Timer expired, so return true
return true;
}
static void dtls1_double_timeout(SSL *ssl) {
ssl->d1->timeout_duration_ms *= 2;
if (ssl->d1->timeout_duration_ms > 60000) {
ssl->d1->timeout_duration_ms = 60000;
}
}
void dtls1_stop_timer(SSL *ssl) {
ssl->d1->num_timeouts = 0;
OPENSSL_memset(&ssl->d1->next_timeout, 0, sizeof(ssl->d1->next_timeout));
ssl->d1->timeout_duration_ms = ssl->initial_timeout_duration_ms;
}
bool dtls1_check_timeout_num(SSL *ssl) {
ssl->d1->num_timeouts++;
// Reduce MTU after 2 unsuccessful retransmissions
if (ssl->d1->num_timeouts > DTLS1_MTU_TIMEOUTS &&
!(SSL_get_options(ssl) & SSL_OP_NO_QUERY_MTU)) {
long mtu =
BIO_ctrl(ssl->wbio.get(), BIO_CTRL_DGRAM_GET_FALLBACK_MTU, 0, nullptr);
if (mtu >= 0 && mtu <= (1 << 30) && (unsigned)mtu >= dtls1_min_mtu()) {
ssl->d1->mtu = (unsigned)mtu;
}
}
if (ssl->d1->num_timeouts > DTLS1_MAX_TIMEOUTS) {
// fail the connection, enough alerts have been sent
OPENSSL_PUT_ERROR(SSL, SSL_R_READ_TIMEOUT_EXPIRED);
return false;
}
return true;
}
BSSL_NAMESPACE_END
using namespace bssl;
void DTLSv1_set_initial_timeout_duration(SSL *ssl, unsigned int duration_ms) {
ssl->initial_timeout_duration_ms = duration_ms;
}
int DTLSv1_get_timeout(const SSL *ssl, struct timeval *out) {
if (!SSL_is_dtls(ssl)) {
return 0;
}
// If no timeout is set, just return 0.
if (ssl->d1->next_timeout.tv_sec == 0 && ssl->d1->next_timeout.tv_usec == 0) {
return 0;
}
struct OPENSSL_timeval timenow;
ssl_get_current_time(ssl, &timenow);
// If timer already expired, set remaining time to 0.
if (ssl->d1->next_timeout.tv_sec < timenow.tv_sec ||
(ssl->d1->next_timeout.tv_sec == timenow.tv_sec &&
ssl->d1->next_timeout.tv_usec <= timenow.tv_usec)) {
OPENSSL_memset(out, 0, sizeof(*out));
return 1;
}
// Calculate time left until timer expires.
struct OPENSSL_timeval ret;
OPENSSL_memcpy(&ret, &ssl->d1->next_timeout, sizeof(ret));
ret.tv_sec -= timenow.tv_sec;
if (ret.tv_usec >= timenow.tv_usec) {
ret.tv_usec -= timenow.tv_usec;
} else {
ret.tv_usec = 1000000 + ret.tv_usec - timenow.tv_usec;
ret.tv_sec--;
}
// If remaining time is less than 15 ms, set it to 0 to prevent issues
// because of small divergences with socket timeouts.
if (ret.tv_sec == 0 && ret.tv_usec < 15000) {
OPENSSL_memset(&ret, 0, sizeof(ret));
}
// Clamp the result in case of overflow.
if (ret.tv_sec > INT_MAX) {
assert(0);
out->tv_sec = INT_MAX;
} else {
out->tv_sec = ret.tv_sec;
}
out->tv_usec = ret.tv_usec;
return 1;
}
int DTLSv1_handle_timeout(SSL *ssl) {
ssl_reset_error_state(ssl);
if (!SSL_is_dtls(ssl)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return -1;
}
// If no timer is expired, don't do anything.
if (!dtls1_is_timer_expired(ssl)) {
return 0;
}
if (!dtls1_check_timeout_num(ssl)) {
return -1;
}
dtls1_double_timeout(ssl);
dtls1_start_timer(ssl);
return dtls1_retransmit_outgoing_messages(ssl);
}