boringssl/include/openssl/dtls1.h
David Benjamin 377fc3160c Document DTLS timeout API and add current_time_cb hook.
This is so the tests needn't be sensitive to the clock. It is, unfortunately, a
test-only hook, but the DTLS retransmit/timeout logic more-or-less requires it
currently. Use this hook to, for now, freeze the clock at zero. This makes the
tests deterministic.

It might be worth designing a saner API in the future. The current one,
notably, requires that the caller's clock be compatible with the one we
internally use. It's also not clear whether the caller needs to call
DTLSv1_handle_timeout or can just rely on the state machine doing it internally
(as it does do). But mock clocks are relatively tame and WebRTC wants to
compile against upstream OpenSSL for now, so we're limited in how much new API
we can build.

Change-Id: I7aad51570596f69275ed0fc1a8892393e4b7ba13
Reviewed-on: https://boringssl-review.googlesource.com/3210
Reviewed-by: Adam Langley <agl@google.com>
2015-02-03 00:39:44 +00:00

244 lines
6.9 KiB
C

/* ssl/dtls1.h */
/*
* 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,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* 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). */
#ifndef HEADER_DTLS1_H
#define HEADER_DTLS1_H
#include <openssl/base.h>
#include <openssl/buf.h>
#include <openssl/pqueue.h>
#ifdef __cplusplus
extern "C" {
#endif
#define DTLS1_VERSION 0xFEFF
#define DTLS1_2_VERSION 0xFEFD
/* lengths of messages */
#define DTLS1_COOKIE_LENGTH 256
#define DTLS1_RT_HEADER_LENGTH 13
#define DTLS1_HM_HEADER_LENGTH 12
#define DTLS1_HM_BAD_FRAGMENT -2
#define DTLS1_HM_FRAGMENT_RETRY -3
#define DTLS1_CCS_HEADER_LENGTH 1
#define DTLS1_AL_HEADER_LENGTH 2
#ifndef OPENSSL_NO_SSL_INTERN
typedef struct dtls1_bitmap_st
{
/* map is a bit mask of the last 64 sequence numbers. Bit
* |1<<i| corresponds to |max_seq_num - i|. */
uint64_t map;
/* max_seq_num is the largest sequence number seen so far. It
* is a 64-bit value in big-endian encoding. */
uint8_t max_seq_num[8];
} DTLS1_BITMAP;
struct dtls1_retransmit_state
{
SSL_AEAD_CTX *aead_write_ctx;
SSL_SESSION *session;
unsigned short epoch;
};
struct hm_header_st
{
unsigned char type;
unsigned long msg_len;
unsigned short seq;
unsigned long frag_off;
unsigned long frag_len;
unsigned int is_ccs;
struct dtls1_retransmit_state saved_retransmit_state;
};
struct ccs_header_st
{
unsigned char type;
unsigned short seq;
};
struct dtls1_timeout_st
{
/* Number of read timeouts so far */
unsigned int read_timeouts;
/* Number of write timeouts so far */
unsigned int write_timeouts;
/* Number of alerts received so far */
unsigned int num_alerts;
};
typedef struct record_pqueue_st
{
unsigned short epoch;
pqueue q;
} record_pqueue;
typedef struct hm_fragment_st
{
struct hm_header_st msg_header;
unsigned char *fragment;
unsigned char *reassembly;
} hm_fragment;
typedef struct dtls1_state_st
{
/* send_cookie is true if we are resending the ClientHello
* with a cookie from a HelloVerifyRequest. */
unsigned int send_cookie;
uint8_t cookie[DTLS1_COOKIE_LENGTH];
size_t cookie_len;
/*
* The current data and handshake epoch. This is initially
* undefined, and starts at zero once the initial handshake is
* completed
*/
unsigned short r_epoch;
unsigned short w_epoch;
/* records being received in the current epoch */
DTLS1_BITMAP bitmap;
/* renegotiation starts a new set of sequence numbers */
DTLS1_BITMAP next_bitmap;
/* handshake message numbers */
unsigned short handshake_write_seq;
unsigned short next_handshake_write_seq;
unsigned short handshake_read_seq;
/* save last sequence number for retransmissions */
unsigned char last_write_sequence[8];
/* Received handshake records (processed and unprocessed) */
record_pqueue unprocessed_rcds;
record_pqueue processed_rcds;
/* Buffered handshake messages */
pqueue buffered_messages;
/* Buffered (sent) handshake records */
pqueue sent_messages;
/* Buffered application records.
* Only for records between CCS and Finished
* to prevent either protocol violation or
* unnecessary message loss.
*/
record_pqueue buffered_app_data;
unsigned int mtu; /* max DTLS packet size */
struct hm_header_st w_msg_hdr;
struct hm_header_st r_msg_hdr;
struct dtls1_timeout_st timeout;
/* Indicates when the last handshake msg or heartbeat sent will
* timeout. Because of header issues on Windows, this cannot actually
* be a struct timeval. */
OPENSSL_timeval next_timeout;
/* Timeout duration */
unsigned short timeout_duration;
/* storage for Alert/Handshake protocol data received but not
* yet processed by ssl3_read_bytes: */
unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH];
unsigned int alert_fragment_len;
unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH];
unsigned int handshake_fragment_len;
unsigned int change_cipher_spec_ok;
} DTLS1_STATE;
typedef struct dtls1_record_data_st
{
unsigned char *packet;
unsigned int packet_length;
SSL3_BUFFER rbuf;
SSL3_RECORD rrec;
} DTLS1_RECORD_DATA;
#endif
/* Timeout multipliers (timeout slice is defined in apps/timeouts.h */
#define DTLS1_TMO_READ_COUNT 2
#define DTLS1_TMO_WRITE_COUNT 2
#define DTLS1_TMO_ALERT_COUNT 12
#ifdef __cplusplus
}
#endif
#endif