lsquic_trans_params.h revision 1bdb91d1 
1/* Copyright (c) 2017 - 2020 LiteSpeed Technologies Inc.  See LICENSE. */
2/*
3 * lsquic_trans_params.h -- Transport parameters types and functions.
4 */
5
6#ifndef LSQUIC_TRANS_PARAMS_H
7#define LSQUIC_TRANS_PARAMS_H 1
8
9/* Transport parameters are grouped by the type of their values: numeric,
10 * empty, and custom.
11 *
12 * The enum values are arbitrary.  The literal transport parameter ID
13 * *values* (e.g. 0x1057 for loss bits) are not exposed by the API.
14 */
15enum transport_param_id
16{
17    /*
18     * Numeric transport parameters that have default values:
19     */
20    TPI_MAX_IDLE_TIMEOUT,
21    TPI_MAX_PACKET_SIZE,
22    TPI_INIT_MAX_DATA,
23    TPI_INIT_MAX_STREAM_DATA_BIDI_LOCAL,
24    TPI_INIT_MAX_STREAM_DATA_BIDI_REMOTE,
25    TPI_INIT_MAX_STREAM_DATA_UNI,
26    TPI_INIT_MAX_STREAMS_BIDI,
27    TPI_INIT_MAX_STREAMS_UNI,
28    TPI_ACK_DELAY_EXPONENT,
29    TPI_MAX_ACK_DELAY,
30    TPI_ACTIVE_CONNECTION_ID_LIMIT,         MAX_NUM_WITH_DEF_TPI = TPI_ACTIVE_CONNECTION_ID_LIMIT,
31
32    /*
33     * Numeric transport parameters without default values:
34     */
35    TPI_LOSS_BITS,                          MAX_NUMERIC_TPI = TPI_LOSS_BITS,
36
37    /*
38     * Empty transport parameters:
39     */
40    TPI_DISABLE_ACTIVE_MIGRATION,           MAX_EMPTY_TPI = TPI_DISABLE_ACTIVE_MIGRATION,
41
42    /*
43     * Custom handlers:
44     */
45    TPI_PREFERRED_ADDRESS,
46    TPI_ORIGINAL_CONNECTION_ID,
47#if LSQUIC_TEST_QUANTUM_READINESS
48    /* https://github.com/quicwg/base-drafts/wiki/Quantum-Readiness-test */
49#define QUANTUM_READY_SZ 1200
50    TPI_QUANTUM_READINESS,
51#endif
52    TPI_STATELESS_RESET_TOKEN,              LAST_TPI = TPI_STATELESS_RESET_TOKEN
53};
54
55
56struct transport_params
57{
58    /* Which transport parameters values are set: */
59    unsigned                tp_set;
60
61    /* Which transport parameters were present (set by the decoder): */
62    unsigned                tp_decoded;
63
64    uint64_t                tp_numerics[MAX_NUMERIC_TPI + 1];
65
66#define tp_init_max_stream_data_bidi_local  tp_numerics[TPI_INIT_MAX_STREAM_DATA_BIDI_LOCAL]
67#define tp_init_max_stream_data_bidi_remote tp_numerics[TPI_INIT_MAX_STREAM_DATA_BIDI_REMOTE]
68#define tp_init_max_stream_data_uni         tp_numerics[TPI_INIT_MAX_STREAM_DATA_UNI]
69#define tp_init_max_data                    tp_numerics[TPI_INIT_MAX_DATA]
70#define tp_max_idle_timeout                 tp_numerics[TPI_MAX_IDLE_TIMEOUT]
71#define tp_init_max_streams_bidi            tp_numerics[TPI_INIT_MAX_STREAMS_BIDI]
72#define tp_init_max_streams_uni             tp_numerics[TPI_INIT_MAX_STREAMS_UNI]
73#define tp_max_packet_size                  tp_numerics[TPI_MAX_PACKET_SIZE]
74#define tp_ack_delay_exponent               tp_numerics[TPI_ACK_DELAY_EXPONENT]
75#define tp_max_ack_delay                    tp_numerics[TPI_MAX_ACK_DELAY]
76#define tp_active_connection_id_limit       tp_numerics[TPI_ACTIVE_CONNECTION_ID_LIMIT]
77#define tp_loss_bits                        tp_numerics[TPI_LOSS_BITS]
78
79    uint8_t     tp_stateless_reset_token[IQUIC_SRESET_TOKEN_SZ];
80    struct {
81        uint8_t         ipv4_addr[4];
82        uint16_t        ipv4_port;
83        uint8_t         ipv6_addr[16];
84        uint16_t        ipv6_port;
85        lsquic_cid_t    cid;
86        uint8_t         srst[IQUIC_SRESET_TOKEN_SZ];
87    }           tp_preferred_address;
88    lsquic_cid_t    tp_original_cid;
89};
90
91#define TP_DEF_MAX_PACKET_SIZE 65527
92#define TP_DEF_ACK_DELAY_EXP 3
93#define TP_DEF_INIT_MAX_STREAMS_UNI 0
94#define TP_DEF_INIT_MAX_STREAMS_BIDI 0
95#define TP_DEF_INIT_MAX_DATA 0
96#define TP_DEF_DISABLE_ACTIVE_MIGRATION 0
97#define TP_DEF_INIT_MAX_STREAM_DATA_BIDI_LOCAL 0
98#define TP_DEF_INIT_MAX_STREAM_DATA_BIDI_REMOTE 0
99#define TP_DEF_INIT_MAX_STREAM_DATA_UNI 0
100#define TP_DEF_MAX_IDLE_TIMEOUT 0
101#define TP_DEF_MAX_ACK_DELAY 25
102#define TP_DEF_ACTIVE_CONNECTION_ID_LIMIT 2
103
104/* [draft-ietf-quic-transport-18], Section 18.1 */
105#define TP_MAX_MAX_ACK_DELAY ((1u << 14) - 1)
106
107#define TP_DEFAULT_VALUES                                                             \
108    .tp_set = ((1 << (MAX_NUM_WITH_DEF_TPI + 1)) - 1),                                \
109    .tp_active_connection_id_limit        =  TP_DEF_ACTIVE_CONNECTION_ID_LIMIT,       \
110    .tp_max_idle_timeout                  =  TP_DEF_MAX_IDLE_TIMEOUT,                 \
111    .tp_max_ack_delay                     =  TP_DEF_MAX_ACK_DELAY,                    \
112    .tp_max_packet_size                   =  TP_DEF_MAX_PACKET_SIZE,                  \
113    .tp_ack_delay_exponent                =  TP_DEF_ACK_DELAY_EXP,                    \
114    .tp_init_max_streams_bidi             =  TP_DEF_INIT_MAX_STREAMS_BIDI,            \
115    .tp_init_max_streams_uni              =  TP_DEF_INIT_MAX_STREAMS_UNI,             \
116    .tp_init_max_data                     =  TP_DEF_INIT_MAX_DATA,                    \
117    .tp_init_max_stream_data_bidi_local   =  TP_DEF_INIT_MAX_STREAM_DATA_BIDI_LOCAL,  \
118    .tp_init_max_stream_data_bidi_remote  =  TP_DEF_INIT_MAX_STREAM_DATA_BIDI_REMOTE, \
119    .tp_init_max_stream_data_uni          =  TP_DEF_INIT_MAX_STREAM_DATA_UNI
120
121#define TP_INITIALIZER() (struct transport_params) { TP_DEFAULT_VALUES }
122
123int
124lsquic_tp_encode (const struct transport_params *, int is_server,
125                  unsigned char *buf, size_t bufsz);
126
127int
128lsquic_tp_decode (const unsigned char *buf, size_t bufsz,
129    /* This argument specifies whose transport parameters we are parsing.  If
130     * true, we are parsing parameters sent by the server; if false, we are
131     * parsing parameteres sent by the client.
132     */
133                  int is_server,
134                  struct transport_params *);
135
136void
137lsquic_tp_to_str (const struct transport_params *params, char *buf, size_t sz);
138
139int
140lsquic_tp_has_pref_ipv4 (const struct transport_params *);
141
142int
143lsquic_tp_has_pref_ipv6 (const struct transport_params *);
144
145#endif
146