lsquic_trans_params.h revision fb3e20e0 
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_UDP_PAYLOAD_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_MIN_ACK_DELAY,
36    TPI_LOSS_BITS,                          MAX_NUMERIC_TPI = TPI_LOSS_BITS,
37
38    /*
39     * Empty transport parameters:
40     */
41    TPI_TIMESTAMPS,
42    TPI_DISABLE_ACTIVE_MIGRATION,           MAX_EMPTY_TPI = TPI_DISABLE_ACTIVE_MIGRATION,
43
44    /*
45     * Custom handlers:
46     */
47    TPI_PREFERRED_ADDRESS,
48        /* CIDs must be in a contiguous range for tp_cids array to work */
49#define FIRST_TP_CID TPI_ORIGINAL_DEST_CID
50    TPI_ORIGINAL_DEST_CID,
51    TPI_INITIAL_SOURCE_CID,
52#define LAST_TP_CID TPI_RETRY_SOURCE_CID
53    TPI_RETRY_SOURCE_CID,
54#if LSQUIC_TEST_QUANTUM_READINESS
55    /* https://github.com/quicwg/base-drafts/wiki/Quantum-Readiness-test */
56#define QUANTUM_READY_SZ 1200
57    TPI_QUANTUM_READINESS,
58#endif
59    TPI_STATELESS_RESET_TOKEN,              LAST_TPI = TPI_STATELESS_RESET_TOKEN
60};
61
62#define TP_CID_IDX(tpi_) ((tpi_) - FIRST_TP_CID)
63
64
65struct transport_params
66{
67    /* Which transport parameters values are set: */
68    unsigned                tp_set;
69
70    /* Which transport parameters were present (set by the decoder): */
71    unsigned                tp_decoded;
72
73    uint64_t                tp_numerics[MAX_NUMERIC_TPI + 1];
74
75#define tp_init_max_stream_data_bidi_local  tp_numerics[TPI_INIT_MAX_STREAM_DATA_BIDI_LOCAL]
76#define tp_init_max_stream_data_bidi_remote tp_numerics[TPI_INIT_MAX_STREAM_DATA_BIDI_REMOTE]
77#define tp_init_max_stream_data_uni         tp_numerics[TPI_INIT_MAX_STREAM_DATA_UNI]
78#define tp_init_max_data                    tp_numerics[TPI_INIT_MAX_DATA]
79#define tp_max_idle_timeout                 tp_numerics[TPI_MAX_IDLE_TIMEOUT]
80#define tp_init_max_streams_bidi            tp_numerics[TPI_INIT_MAX_STREAMS_BIDI]
81#define tp_init_max_streams_uni             tp_numerics[TPI_INIT_MAX_STREAMS_UNI]
82#define tp_max_udp_payload_size             tp_numerics[TPI_MAX_UDP_PAYLOAD_SIZE]
83#define tp_ack_delay_exponent               tp_numerics[TPI_ACK_DELAY_EXPONENT]
84#define tp_max_ack_delay                    tp_numerics[TPI_MAX_ACK_DELAY]
85#define tp_active_connection_id_limit       tp_numerics[TPI_ACTIVE_CONNECTION_ID_LIMIT]
86#define tp_loss_bits                        tp_numerics[TPI_LOSS_BITS]
87
88    uint8_t     tp_stateless_reset_token[IQUIC_SRESET_TOKEN_SZ];
89    struct {
90        uint8_t         ipv4_addr[4];
91        uint16_t        ipv4_port;
92        uint8_t         ipv6_addr[16];
93        uint16_t        ipv6_port;
94        lsquic_cid_t    cid;
95        uint8_t         srst[IQUIC_SRESET_TOKEN_SZ];
96    }           tp_preferred_address;
97    lsquic_cid_t    tp_cids[3];
98#define tp_original_dest_cid tp_cids[TP_CID_IDX(TPI_ORIGINAL_DEST_CID)]
99#define tp_initial_source_cid tp_cids[TP_CID_IDX(TPI_INITIAL_SOURCE_CID)]
100#define tp_retry_source_cid tp_cids[TP_CID_IDX(TPI_RETRY_SOURCE_CID)]
101};
102
103#define MAX_TP_STR_SZ ((LAST_TPI + 1) *                                     \
104    (34 /* longest entry in tt2str */ + 2 /* semicolon */ + 2 /* colon */)  \
105  + INET_ADDRSTRLEN + INET6_ADDRSTRLEN + 5 /* Port */ * 2                   \
106  + MAX_CID_LEN * 2 * 4 /* there are four CIDs */                           \
107  + 11 * (MAX_NUMERIC_TPI + 1)                                              \
108  + IQUIC_SRESET_TOKEN_SZ * 2 * 2 /* there are two reset tokens */)
109
110#define TP_DEF_MAX_UDP_PAYLOAD_SIZE 65527
111#define TP_DEF_ACK_DELAY_EXP 3
112#define TP_DEF_INIT_MAX_STREAMS_UNI 0
113#define TP_DEF_INIT_MAX_STREAMS_BIDI 0
114#define TP_DEF_INIT_MAX_DATA 0
115#define TP_DEF_DISABLE_ACTIVE_MIGRATION 0
116#define TP_DEF_INIT_MAX_STREAM_DATA_BIDI_LOCAL 0
117#define TP_DEF_INIT_MAX_STREAM_DATA_BIDI_REMOTE 0
118#define TP_DEF_INIT_MAX_STREAM_DATA_UNI 0
119#define TP_DEF_MAX_IDLE_TIMEOUT 0
120#define TP_DEF_MAX_ACK_DELAY 25
121#define TP_DEF_ACTIVE_CONNECTION_ID_LIMIT 2
122
123/* [draft-ietf-quic-transport-18], Section 18.1 */
124#define TP_MAX_MAX_ACK_DELAY ((1u << 14) - 1)
125
126#define TP_DEFAULT_VALUES                                                             \
127    .tp_set = ((1 << (MAX_NUM_WITH_DEF_TPI + 1)) - 1),                                \
128    .tp_active_connection_id_limit        =  TP_DEF_ACTIVE_CONNECTION_ID_LIMIT,       \
129    .tp_max_idle_timeout                  =  TP_DEF_MAX_IDLE_TIMEOUT,                 \
130    .tp_max_ack_delay                     =  TP_DEF_MAX_ACK_DELAY,                    \
131    .tp_max_udp_payload_size              =  TP_DEF_MAX_UDP_PAYLOAD_SIZE,             \
132    .tp_ack_delay_exponent                =  TP_DEF_ACK_DELAY_EXP,                    \
133    .tp_init_max_streams_bidi             =  TP_DEF_INIT_MAX_STREAMS_BIDI,            \
134    .tp_init_max_streams_uni              =  TP_DEF_INIT_MAX_STREAMS_UNI,             \
135    .tp_init_max_data                     =  TP_DEF_INIT_MAX_DATA,                    \
136    .tp_init_max_stream_data_bidi_local   =  TP_DEF_INIT_MAX_STREAM_DATA_BIDI_LOCAL,  \
137    .tp_init_max_stream_data_bidi_remote  =  TP_DEF_INIT_MAX_STREAM_DATA_BIDI_REMOTE, \
138    .tp_init_max_stream_data_uni          =  TP_DEF_INIT_MAX_STREAM_DATA_UNI
139
140#define TP_INITIALIZER() (struct transport_params) { TP_DEFAULT_VALUES }
141
142int
143lsquic_tp_encode (const struct transport_params *, int is_server,
144                  unsigned char *const buf, size_t bufsz);
145
146int
147lsquic_tp_decode (const unsigned char *const buf, size_t bufsz,
148    /* This argument specifies whose transport parameters we are parsing.  If
149     * true, we are parsing parameters sent by the server; if false, we are
150     * parsing parameteres sent by the client.
151     */
152                  int is_server,
153                  struct transport_params *);
154
155void
156lsquic_tp_to_str (const struct transport_params *params, char *buf, size_t sz);
157
158int
159lsquic_tp_encode_27 (const struct transport_params *, int is_server,
160                  unsigned char *const buf, size_t bufsz);
161
162int
163lsquic_tp_decode_27 (const unsigned char *const buf, size_t bufsz,
164                  int is_server,
165                  struct transport_params *);
166
167void
168lsquic_tp_to_str_27 (const struct transport_params *params, char *buf, size_t sz);
169
170int
171lsquic_tp_has_pref_ipv4 (const struct transport_params *);
172
173int
174lsquic_tp_has_pref_ipv6 (const struct transport_params *);
175
176extern const char * const lsquic_tpi2str[LAST_TPI + 1];
177
178#endif
179