1/* $OpenBSD: tls13_record.h,v 1.5 2021/10/23 13:12:14 jsing Exp $ */
2/*
3 * Copyright (c) 2019 Joel Sing <jsing@openbsd.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18#ifndef HEADER_TLS13_RECORD_H
19#define HEADER_TLS13_RECORD_H
20
21#include "bytestring.h"
22
23__BEGIN_HIDDEN_DECLS
24
25/*
26 * TLSv1.3 Record Protocol - RFC 8446 section 5.
27 *
28 * The maximum plaintext is 2^14, however for inner plaintext an additional
29 * byte is allowed for the content type. A maximum AEAD overhead of 255-bytes
30 * is permitted, along with a 5-byte header, giving a maximum size of
31 * 5 + 2^14 + 1 + 255 = 16,645-bytes.
32 */
33#define TLS13_RECORD_HEADER_LEN			5
34#define TLS13_RECORD_MAX_AEAD_OVERHEAD		255
35#define TLS13_RECORD_MAX_PLAINTEXT_LEN		16384
36#define TLS13_RECORD_MAX_INNER_PLAINTEXT_LEN \
37	(TLS13_RECORD_MAX_PLAINTEXT_LEN + 1)
38#define TLS13_RECORD_MAX_CIPHERTEXT_LEN \
39	(TLS13_RECORD_MAX_INNER_PLAINTEXT_LEN + TLS13_RECORD_MAX_AEAD_OVERHEAD)
40#define TLS13_RECORD_MAX_LEN \
41	(TLS13_RECORD_HEADER_LEN + TLS13_RECORD_MAX_CIPHERTEXT_LEN)
42
43/*
44 * TLSv1.3 Per-Record Nonces and Sequence Numbers - RFC 8446 section 5.3.
45 */
46#define TLS13_RECORD_SEQ_NUM_LEN 8
47
48struct tls13_record;
49
50struct tls13_record *tls13_record_new(void);
51void tls13_record_free(struct tls13_record *_rec);
52uint16_t tls13_record_version(struct tls13_record *_rec);
53uint8_t tls13_record_content_type(struct tls13_record *_rec);
54int tls13_record_header(struct tls13_record *_rec, CBS *_cbs);
55int tls13_record_content(struct tls13_record *_rec, CBS *_cbs);
56void tls13_record_data(struct tls13_record *_rec, CBS *_cbs);
57int tls13_record_set_data(struct tls13_record *_rec, uint8_t *_data,
58    size_t _data_len);
59ssize_t tls13_record_recv(struct tls13_record *_rec, tls_read_cb _wire_read,
60    void *_wire_arg);
61ssize_t tls13_record_send(struct tls13_record *_rec, tls_write_cb _wire_write,
62    void *_wire_arg);
63
64__END_HIDDEN_DECLS
65
66#endif
67