1/* Copyright (c) 2017 - 2022 LiteSpeed Technologies Inc.  See LICENSE. */
2/*
3 * lsquic_mini_conn_ietf.h -- Mini connection used by the IETF QUIC
4 */
5
6#ifndef LSQUIC_MINI_CONN_IETF_H
7#define LSQUIC_MINI_CONN_IETF_H 1
8
9struct lsquic_conn;
10struct lsquic_engine_public;
11struct lsquic_packet_in;
12
13enum { MCSBIT_WANTREAD, MCSBIT_WANTWRITE, };
14
15struct mini_crypto_stream
16{
17    unsigned        mcs_read_off;
18    unsigned        mcs_write_off;
19    enum {
20        MCS_WANTREAD    = 1 << MCSBIT_WANTREAD,
21        MCS_WANTWRITE   = 1 << MCSBIT_WANTWRITE,
22        MCS_CREATED     = 1 << 2,
23    }               mcs_flags:8;
24    enum enc_level  mcs_enc_level:8;
25};
26
27typedef uint64_t packno_set_t;
28#define MAX_PACKETS ((sizeof(packno_set_t) * 8) - 1)
29
30/* We do not handle packets in the App packet number space in the mini
31 * connection.  They are all buffered to be handled later when the
32 * connection is promoted.  This means we do not have to have data
33 * structures to track the App PNS.
34 */
35#define IMICO_N_PNS (N_PNS - 1)
36
37struct ietf_mini_conn
38{
39    struct lsquic_conn              imc_conn;
40    struct conn_cid_elem            imc_cces[3];
41    struct lsquic_engine_public    *imc_enpub;
42    lsquic_time_t                   imc_created;
43    enum {
44        IMC_ENC_SESS_INITED     = 1 << 0,
45        IMC_QUEUED_ACK_INIT     = 1 << 1,
46        IMC_QUEUED_ACK_HSK      = IMC_QUEUED_ACK_INIT << PNS_HSK,
47        IMC_UNUSED3             = 1 << 3,
48        IMC_ERROR               = 1 << 4,
49        IMC_HSK_OK              = 1 << 5,
50        IMC_HSK_FAILED          = 1 << 6,
51        IMC_HAVE_TP             = 1 << 7,
52        IMC_RETRY_MODE          = 1 << 8,
53        IMC_RETRY_DONE          = 1 << 9,
54        IMC_IGNORE_INIT         = 1 << 10,
55#define IMCBIT_PNS_BIT_SHIFT 11
56        IMC_MAX_PNS_BIT_0       = 1 << 11,
57        IMC_MAX_PNS_BIT_1       = 1 << 12,
58        IMC_TLS_ALERT           = 1 << 13,
59        IMC_ABORT_ERROR         = 1 << 14,
60        IMC_ABORT_ISAPP         = 1 << 15,
61        IMC_BAD_TRANS_PARAMS    = 1 << 16,
62        IMC_ADDR_VALIDATED      = 1 << 17,
63        IMC_HSK_PACKET_SENT     = 1 << 18,
64        IMC_CLOSE_RECVD         = 1 << 19,
65        IMC_PARSE_FAILED        = 1 << 20,
66        IMC_PATH_CHANGED        = 1 << 21,
67        IMC_HSK_DONE_SENT       = 1 << 22,
68        IMC_TRECHIST            = 1 << 23,
69    }                               imc_flags;
70    struct mini_crypto_stream       imc_streams[N_ENC_LEVS];
71    void                           *imc_stream_ps[N_ENC_LEVS];
72    struct {
73        struct stream_frame    *frame;   /* Latest frame - on stack - be careful. */
74        enum enc_level          enc_level;
75    }                               imc_last_in;
76    TAILQ_HEAD(, lsquic_packet_in)  imc_app_packets;
77    TAILQ_HEAD(, lsquic_packet_out) imc_packets_out;
78    TAILQ_HEAD(, stream_frame)      imc_crypto_frames;
79    packno_set_t                    imc_sent_packnos;
80    union {
81        packno_set_t                    bitmasks[IMICO_N_PNS];
82        struct {
83            struct trechist_elem       *hist_elems;
84            trechist_mask_t             hist_masks[IMICO_N_PNS];
85        }                           trechist;
86    }                               imc_recvd_packnos;
87    packno_set_t                    imc_acked_packnos[IMICO_N_PNS];
88    lsquic_time_t                   imc_largest_recvd[IMICO_N_PNS];
89    struct lsquic_rtt_stats         imc_rtt_stats;
90    unsigned                        imc_error_code;
91    unsigned                        imc_bytes_in;
92    unsigned                        imc_bytes_out;
93    unsigned short                  imc_crypto_frames_sz;
94    /* We need to read in the length of ClientHello to check when we have fed
95     * it to the crypto layer.
96     */
97    unsigned short                  imc_ch_len;
98    unsigned char                   imc_next_packno;
99    unsigned char                   imc_hsk_count;
100    /* We don't send more than eight in the first flight, and so it's OK to
101     * use uint8_t.  This value is also used as a boolean: when ECN black
102     * hole is detected, it is set to zero to indicate that black hole
103     * detection is no longer active.
104     */
105    uint8_t                         imc_ecn_packnos;
106    uint8_t                         imc_ack_exp;
107    uint8_t                         imc_ecn_counts_in[IMICO_N_PNS][4];
108    uint8_t                         imc_incoming_ecn;
109    uint8_t                         imc_tls_alert;
110#define IMICO_MAX_DELAYED_PACKETS_UNVALIDATED 1u
111#define IMICO_MAX_DELAYED_PACKETS_VALIDATED 2u
112    unsigned char                   imc_delayed_packets_count;
113#define IMICO_MAX_STASHED_FRAMES 10u
114    unsigned char                   imc_n_crypto_frames;
115    struct network_path             imc_path;
116};
117
118/* [draft-ietf-quic-transport-24] Section 7.4
119 *
120 " Implementations MUST support buffering at least 4096 bytes of data
121 " received in CRYPTO frames out of order.  Endpoints MAY choose to
122 " allow more data to be buffered during the handshake.  A larger limit
123 " during the handshake could allow for larger keys or credentials to be
124 " exchanged.  An endpoint's buffer size does not need to remain
125 " constant during the life of the connection.
126 */
127#define IMICO_MAX_BUFFERED_CRYPTO (6u * 1024u)
128
129struct lsquic_conn *
130lsquic_mini_conn_ietf_new (struct lsquic_engine_public *,
131               const struct lsquic_packet_in *,
132               enum lsquic_version, int is_ipv4, const struct lsquic_cid *,
133               size_t udp_payload_size);
134
135int
136lsquic_mini_conn_ietf_ecn_ok (const struct ietf_mini_conn *);
137
138struct ietf_mini_rechist
139{
140    const struct ietf_mini_conn *conn;
141    enum packnum_space           pns;
142    union {
143        struct {
144            packno_set_t                 cur_set;
145            struct lsquic_packno_range   range;   /* We return a pointer to this */
146            int                          cur_idx;
147        }                       bitmask;
148        struct trechist_iter    trechist_iter;
149    } u;
150};
151
152void
153lsquic_imico_rechist_init (struct ietf_mini_rechist *rechist,
154                const struct ietf_mini_conn *conn, enum packnum_space pns);
155
156const struct lsquic_packno_range *
157lsquic_imico_rechist_first (void *rechist_ctx);
158
159const struct lsquic_packno_range *
160lsquic_imico_rechist_next (void *rechist_ctx);
161
162#endif
163