lsquic_packet_out.h revision 9626cfc2
110c492f0SDmitri Tikhonov/* Copyright (c) 2017 - 2018 LiteSpeed Technologies Inc.  See LICENSE. */
250aadb33SDmitri Tikhonov/*
350aadb33SDmitri Tikhonov * lsquic_packet_out.h -- Structure and routines dealing with packet_out
450aadb33SDmitri Tikhonov */
550aadb33SDmitri Tikhonov
650aadb33SDmitri Tikhonov#ifndef LSQUIC_PACKET_OUT_H
750aadb33SDmitri Tikhonov#define LSQUIC_PACKET_OUT_H 1
850aadb33SDmitri Tikhonov
950aadb33SDmitri Tikhonov#include <sys/queue.h>
1050aadb33SDmitri Tikhonov
1150aadb33SDmitri Tikhonovstruct malo;
129626cfc2SDmitri Tikhonovstruct lsquic_conn;
1350aadb33SDmitri Tikhonovstruct lsquic_engine_public;
1450aadb33SDmitri Tikhonovstruct lsquic_mm;
1550aadb33SDmitri Tikhonovstruct lsquic_stream;
1650aadb33SDmitri Tikhonovstruct parse_funcs;
1750aadb33SDmitri Tikhonov
1850aadb33SDmitri Tikhonov/* Each stream_rec is associated with one packet_out.  packet_out can have
1950aadb33SDmitri Tikhonov * zero or more stream_rec structures.  stream_rec keeps a pointer to a stream
2050aadb33SDmitri Tikhonov * that has STREAM or RST_STREAM frames inside packet_out.  `sr_frame_types'
2150aadb33SDmitri Tikhonov * is a bitmask that records which of these two frames are in the packet.
22c51ce338SDmitri Tikhonov * If this value is zero, values of the other struct members are not valid.
23c51ce338SDmitri Tikhonov * `sr_off' indicates where inside packet_out->po_data STREAM frame begins
24c51ce338SDmitri Tikhonov * and `sr_len' is its length.  These values are not kept for RST_STREAM
25c51ce338SDmitri Tikhonov * frames.
2650aadb33SDmitri Tikhonov *
27c51ce338SDmitri Tikhonov * We need this information for three reasons:
2850aadb33SDmitri Tikhonov *   1. A stream is not destroyed until all of its STREAM and RST_STREAM
2950aadb33SDmitri Tikhonov *      frames are acknowledged.  This is to make sure that we do not exceed
3050aadb33SDmitri Tikhonov *      maximum allowed number of streams.
3150aadb33SDmitri Tikhonov *   2. When a packet is resubmitted, STREAM frames for a stream that has
3250aadb33SDmitri Tikhonov *      been reset are not to be resubmitted.
33c51ce338SDmitri Tikhonov *   3. A buffered packet may have to be split before it is scheduled (this
34c51ce338SDmitri Tikhonov *      occurs if we guessed incorrectly the number of bytes required to
35c51ce338SDmitri Tikhonov *      encode the packet number and the actual number would make packet
36c51ce338SDmitri Tikhonov *      larger than the max).
37c51ce338SDmitri Tikhonov *
3850aadb33SDmitri Tikhonov */
3950aadb33SDmitri Tikhonovstruct stream_rec {
4050aadb33SDmitri Tikhonov    struct lsquic_stream    *sr_stream;
41c51ce338SDmitri Tikhonov    unsigned short           sr_off,
42c51ce338SDmitri Tikhonov                             sr_len;
43bfc7bfd8SDmitri Tikhonov    enum quic_ft_bit         sr_frame_types:16;
4450aadb33SDmitri Tikhonov};
4550aadb33SDmitri Tikhonov
4650aadb33SDmitri Tikhonov#define srec_taken(srec) ((srec)->sr_frame_types)
4750aadb33SDmitri Tikhonov
4850aadb33SDmitri Tikhonovstruct stream_rec_arr {
49c51ce338SDmitri Tikhonov    TAILQ_ENTRY(stream_rec_arr)     next_stream_rec_arr;
5050aadb33SDmitri Tikhonov    struct stream_rec               srecs[
5150aadb33SDmitri Tikhonov      ( 64                              /* Efficient size for malo allocator */
52c51ce338SDmitri Tikhonov      - sizeof(TAILQ_ENTRY(stream_rec)) /* next_stream_rec_arr */
5350aadb33SDmitri Tikhonov      ) / sizeof(struct stream_rec)
5450aadb33SDmitri Tikhonov    ];
5550aadb33SDmitri Tikhonov};
5650aadb33SDmitri Tikhonov
57c51ce338SDmitri TikhonovTAILQ_HEAD(stream_rec_arr_tailq, stream_rec_arr);
58c51ce338SDmitri Tikhonov
5950aadb33SDmitri Tikhonovtypedef struct lsquic_packet_out
6050aadb33SDmitri Tikhonov{
6150aadb33SDmitri Tikhonov    /* `po_next' is used for packets_out, unacked_packets and expired_packets
6250aadb33SDmitri Tikhonov     * lists.
6350aadb33SDmitri Tikhonov     */
6450aadb33SDmitri Tikhonov    TAILQ_ENTRY(lsquic_packet_out)
6550aadb33SDmitri Tikhonov                       po_next;
6650aadb33SDmitri Tikhonov    lsquic_time_t      po_sent;       /* Time sent */
6750aadb33SDmitri Tikhonov    lsquic_packno_t    po_packno;
6850aadb33SDmitri Tikhonov
69bfc7bfd8SDmitri Tikhonov    enum packet_out_flags {
70bfc7bfd8SDmitri Tikhonov        PO_HELLO    = (1 << 1),         /* Packet contains SHLO or CHLO data */
71bfc7bfd8SDmitri Tikhonov        PO_ENCRYPTED= (1 << 3),         /* po_enc_data has encrypted data */
72bfc7bfd8SDmitri Tikhonov        PO_SREC_ARR = (1 << 4),
73bfc7bfd8SDmitri Tikhonov#define POBIT_SHIFT 5
74bfc7bfd8SDmitri Tikhonov        PO_BITS_0   = (1 << 5),         /* PO_BITS_0 and PO_BITS_1 encode the */
75bfc7bfd8SDmitri Tikhonov        PO_BITS_1   = (1 << 6),         /*   packet number length.  See macros below. */
76bfc7bfd8SDmitri Tikhonov        PO_NONCE    = (1 << 7),         /* Use value in `po_nonce' to generate header */
77bfc7bfd8SDmitri Tikhonov        PO_VERSION  = (1 << 8),         /* Use value in `po_ver_tag' to generate header */
78bfc7bfd8SDmitri Tikhonov        PO_CONN_ID  = (1 << 9),         /* Include connection ID in public header */
79bfc7bfd8SDmitri Tikhonov        PO_REPACKNO = (1 <<10),         /* Regenerate packet number */
80bfc7bfd8SDmitri Tikhonov        PO_NOENCRYPT= (1 <<11),         /* Do not encrypt data in po_data */
81bfc7bfd8SDmitri Tikhonov        PO_VERNEG   = (1 <<12),         /* Version negotiation packet. */
82bfc7bfd8SDmitri Tikhonov        PO_STREAM_END
83bfc7bfd8SDmitri Tikhonov                    = (1 <<13),         /* STREAM frame reaches the end of the packet: no
84bfc7bfd8SDmitri Tikhonov                                         * further writes are allowed.
85bfc7bfd8SDmitri Tikhonov                                         */
86bfc7bfd8SDmitri Tikhonov        PO_SCHED    = (1 <<14),         /* On scheduled queue */
8716a9b66aSDmitri Tikhonov        PO_SENT_SZ  = (1 <<15),
889626cfc2SDmitri Tikhonov        PO_LONGHEAD = (1 <<16),
899626cfc2SDmitri Tikhonov        PO_GQUIC    = (1 <<17),         /* Used for logging */
909626cfc2SDmitri Tikhonov#define POLEV_SHIFT 18
919626cfc2SDmitri Tikhonov        PO_BITS_2   = (1 <<18),         /* PO_BITS_2 and PO_BITS_3 encode the */
929626cfc2SDmitri Tikhonov        PO_BITS_3   = (1 <<19),         /*   crypto level.  Used for logging. */
939626cfc2SDmitri Tikhonov    }                  po_flags;
94bfc7bfd8SDmitri Tikhonov    enum quic_ft_bit   po_frame_types:16; /* Bitmask of QUIC_FRAME_* */
95bfc7bfd8SDmitri Tikhonov    unsigned short     po_data_sz;      /* Number of usable bytes in data */
96bfc7bfd8SDmitri Tikhonov    unsigned short     po_enc_data_sz;  /* Number of usable bytes in data */
9716a9b66aSDmitri Tikhonov    unsigned short     po_sent_sz;      /* If PO_SENT_SZ is set, real size of sent buffer. */
98bfc7bfd8SDmitri Tikhonov    unsigned short     po_regen_sz;     /* Number of bytes at the beginning
99bfc7bfd8SDmitri Tikhonov                                         * of data containing bytes that are
100bfc7bfd8SDmitri Tikhonov                                         * not to be retransmitted, e.g. ACK
101bfc7bfd8SDmitri Tikhonov                                         * frames.
102bfc7bfd8SDmitri Tikhonov                                         */
103bfc7bfd8SDmitri Tikhonov    unsigned short     po_n_alloc;      /* Total number of bytes allocated in po_data */
1049626cfc2SDmitri Tikhonov    enum header_type   po_header_type:8;
105bfc7bfd8SDmitri Tikhonov    unsigned char     *po_data;
10616a9b66aSDmitri Tikhonov    lsquic_packno_t    po_ack2ed;       /* If packet has ACK frame, value of
10716a9b66aSDmitri Tikhonov                                         * largest acked in it.
10816a9b66aSDmitri Tikhonov                                         */
109bfc7bfd8SDmitri Tikhonov
11050aadb33SDmitri Tikhonov    /* A lot of packets contain data belonging to only one stream.  Thus,
111c51ce338SDmitri Tikhonov     * `one' is used first.  If this is not enough, any number of
11250aadb33SDmitri Tikhonov     * stream_rec_arr structures can be allocated to handle more stream
11350aadb33SDmitri Tikhonov     * records.
11450aadb33SDmitri Tikhonov     */
115c51ce338SDmitri Tikhonov    union {
116c51ce338SDmitri Tikhonov        struct stream_rec               one;
117c51ce338SDmitri Tikhonov        struct stream_rec_arr_tailq     arr;
118c51ce338SDmitri Tikhonov    }                  po_srecs;
11950aadb33SDmitri Tikhonov
12050aadb33SDmitri Tikhonov    /* If PO_ENCRYPTED is set, this points to the buffer that holds encrypted
12150aadb33SDmitri Tikhonov     * data.
12250aadb33SDmitri Tikhonov     */
12350aadb33SDmitri Tikhonov    unsigned char     *po_enc_data;
12450aadb33SDmitri Tikhonov
12550aadb33SDmitri Tikhonov    lsquic_ver_tag_t   po_ver_tag;      /* Set if PO_VERSION is set */
12650aadb33SDmitri Tikhonov    unsigned char     *po_nonce;        /* Use to generate header if PO_NONCE is set */
12750aadb33SDmitri Tikhonov} lsquic_packet_out_t;
12850aadb33SDmitri Tikhonov
12950aadb33SDmitri Tikhonov/* The size of lsquic_packet_out_t could be further reduced:
13050aadb33SDmitri Tikhonov *
13150aadb33SDmitri Tikhonov * po_ver_tag could be encoded as a few bits representing enum lsquic_version
13250aadb33SDmitri Tikhonov * in po_flags.  The cost is a bit of complexity.  This will save us four bytes.
13350aadb33SDmitri Tikhonov */
13450aadb33SDmitri Tikhonov
13550aadb33SDmitri Tikhonov#define lsquic_packet_out_avail(p) ((unsigned short) \
13650aadb33SDmitri Tikhonov                                        ((p)->po_n_alloc - (p)->po_data_sz))
13750aadb33SDmitri Tikhonov
13850aadb33SDmitri Tikhonov#define lsquic_packet_out_packno_bits(p) (((p)->po_flags >> POBIT_SHIFT) & 0x3)
13950aadb33SDmitri Tikhonov
140bfc7bfd8SDmitri Tikhonov#define lsquic_packet_out_set_packno_bits(p, b) do {                    \
141bfc7bfd8SDmitri Tikhonov    (p)->po_flags &= ~(0x3 << POBIT_SHIFT);                             \
142bfc7bfd8SDmitri Tikhonov    (p)->po_flags |= ((b) & 0x3) << POBIT_SHIFT;                        \
143bfc7bfd8SDmitri Tikhonov} while (0)
144bfc7bfd8SDmitri Tikhonov
1459626cfc2SDmitri Tikhonov#define lsquic_po_header_length(lconn, po_flags) ( \
1469626cfc2SDmitri Tikhonov    lconn->cn_pf->pf_packout_header_size(lconn, po_flags))
14750aadb33SDmitri Tikhonov
1489626cfc2SDmitri Tikhonov#define lsquic_packet_out_total_sz(lconn, p) (\
1499626cfc2SDmitri Tikhonov    lconn->cn_pf->pf_packout_size(lconn, p))
150bfc7bfd8SDmitri Tikhonov
15116a9b66aSDmitri Tikhonov#if __GNUC__
15216a9b66aSDmitri Tikhonov#if LSQUIC_EXTRA_CHECKS
1539626cfc2SDmitri Tikhonov#define lsquic_packet_out_sent_sz(lconn, p) (                               \
15416a9b66aSDmitri Tikhonov        __builtin_expect(((p)->po_flags & PO_SENT_SZ), 1) ?                 \
1559626cfc2SDmitri Tikhonov        (assert((p)->po_sent_sz == lsquic_packet_out_total_sz(lconn, p)),   \
1569626cfc2SDmitri Tikhonov            (p)->po_sent_sz) : lsquic_packet_out_total_sz(lconn, p))
15716a9b66aSDmitri Tikhonov#   else
1589626cfc2SDmitri Tikhonov#define lsquic_packet_out_sent_sz(lconn, p) (                               \
15916a9b66aSDmitri Tikhonov        __builtin_expect(((p)->po_flags & PO_SENT_SZ), 1) ?                 \
1609626cfc2SDmitri Tikhonov        (p)->po_sent_sz : lsquic_packet_out_total_sz(lconn, p))
16116a9b66aSDmitri Tikhonov#endif
16216a9b66aSDmitri Tikhonov#else
1639626cfc2SDmitri Tikhonov#   define lsquic_packet_out_sent_sz(lconn, p) (                            \
16416a9b66aSDmitri Tikhonov        (p)->po_flags & PO_SENT_SZ ?                                        \
1659626cfc2SDmitri Tikhonov        (p)->po_sent_sz : lsquic_packet_out_total_sz(lconn, p))
16616a9b66aSDmitri Tikhonov#endif
16716a9b66aSDmitri Tikhonov
16850aadb33SDmitri Tikhonov#define lsquic_packet_out_verneg(p) \
16950aadb33SDmitri Tikhonov    (((p)->po_flags & (PO_NOENCRYPT|PO_VERNEG)) == (PO_NOENCRYPT|PO_VERNEG))
17050aadb33SDmitri Tikhonov
17150aadb33SDmitri Tikhonov#define lsquic_packet_out_pubres(p) \
17250aadb33SDmitri Tikhonov    (((p)->po_flags & (PO_NOENCRYPT|PO_VERNEG)) ==  PO_NOENCRYPT           )
17350aadb33SDmitri Tikhonov
1749626cfc2SDmitri Tikhonov#define lsquic_packet_out_set_enc_level(p, level) do {                      \
1759626cfc2SDmitri Tikhonov    (p)->po_flags &= ~(3 << POLEV_SHIFT);                                   \
1769626cfc2SDmitri Tikhonov    (p)->po_flags |= level << POLEV_SHIFT;                                  \
1779626cfc2SDmitri Tikhonov} while (0)
1789626cfc2SDmitri Tikhonov
1799626cfc2SDmitri Tikhonov#define lsquic_packet_out_enc_level(p)  (((p)->po_flags >> POLEV_SHIFT) & 3)
1809626cfc2SDmitri Tikhonov
18150aadb33SDmitri Tikhonovstruct packet_out_srec_iter {
18250aadb33SDmitri Tikhonov    lsquic_packet_out_t         *packet_out;
18350aadb33SDmitri Tikhonov    struct stream_rec_arr       *cur_srec_arr;
18450aadb33SDmitri Tikhonov    unsigned                     srec_idx;
185c51ce338SDmitri Tikhonov    int                          impl_idx;
18650aadb33SDmitri Tikhonov};
18750aadb33SDmitri Tikhonov
18850aadb33SDmitri Tikhonovstruct stream_rec *
18950aadb33SDmitri Tikhonovposi_first (struct packet_out_srec_iter *posi, lsquic_packet_out_t *);
19050aadb33SDmitri Tikhonov
19150aadb33SDmitri Tikhonovstruct stream_rec *
19250aadb33SDmitri Tikhonovposi_next (struct packet_out_srec_iter *posi);
19350aadb33SDmitri Tikhonov
19450aadb33SDmitri Tikhonovlsquic_packet_out_t *
19550aadb33SDmitri Tikhonovlsquic_packet_out_new (struct lsquic_mm *, struct malo *, int use_cid,
1969626cfc2SDmitri Tikhonov                       const struct lsquic_conn *, enum lsquic_packno_bits,
19750aadb33SDmitri Tikhonov                       const lsquic_ver_tag_t *, const unsigned char *nonce);
19850aadb33SDmitri Tikhonov
19950aadb33SDmitri Tikhonovvoid
20050aadb33SDmitri Tikhonovlsquic_packet_out_destroy (lsquic_packet_out_t *,
20150aadb33SDmitri Tikhonov                                        struct lsquic_engine_public *);
20250aadb33SDmitri Tikhonov
20350aadb33SDmitri Tikhonovint
20450aadb33SDmitri Tikhonovlsquic_packet_out_add_stream (lsquic_packet_out_t *packet_out,
20550aadb33SDmitri Tikhonov                              struct lsquic_mm *mm,
20650aadb33SDmitri Tikhonov                              struct lsquic_stream *new_stream,
20750aadb33SDmitri Tikhonov                              enum QUIC_FRAME_TYPE,
208c51ce338SDmitri Tikhonov                              unsigned short off, unsigned short len);
20950aadb33SDmitri Tikhonov
210bfc7bfd8SDmitri Tikhonovunsigned
211c51ce338SDmitri Tikhonovlsquic_packet_out_elide_reset_stream_frames (lsquic_packet_out_t *, uint32_t);
212c51ce338SDmitri Tikhonov
213c51ce338SDmitri Tikhonovint
214c51ce338SDmitri Tikhonovlsquic_packet_out_split_in_two (struct lsquic_mm *, lsquic_packet_out_t *,
215c51ce338SDmitri Tikhonov    lsquic_packet_out_t *, const struct parse_funcs *, unsigned excess_bytes);
21650aadb33SDmitri Tikhonov
21750aadb33SDmitri Tikhonovvoid
21850aadb33SDmitri Tikhonovlsquic_packet_out_chop_regen (lsquic_packet_out_t *);
21950aadb33SDmitri Tikhonov
220c51ce338SDmitri Tikhonovint
221c51ce338SDmitri Tikhonovlsquic_packet_out_has_frame (struct lsquic_packet_out *,
222c51ce338SDmitri Tikhonov                        const struct lsquic_stream *, enum QUIC_FRAME_TYPE);
223c51ce338SDmitri Tikhonov
224c51ce338SDmitri Tikhonovint
225c51ce338SDmitri Tikhonovlsquic_packet_out_has_hsk_frames (struct lsquic_packet_out *);
226c51ce338SDmitri Tikhonov
227c51ce338SDmitri Tikhonovvoid
228c51ce338SDmitri Tikhonovlsquic_packet_out_ack_streams (struct lsquic_packet_out *);
229c51ce338SDmitri Tikhonov
230c51ce338SDmitri Tikhonovvoid
231c51ce338SDmitri Tikhonovlsquic_packet_out_zero_pad (struct lsquic_packet_out *);
232c51ce338SDmitri Tikhonov
233c51ce338SDmitri Tikhonovsize_t
234c51ce338SDmitri Tikhonovlsquic_packet_out_mem_used (const struct lsquic_packet_out *);
235c51ce338SDmitri Tikhonov
236c51ce338SDmitri Tikhonovint
237c51ce338SDmitri Tikhonovlsquic_packet_out_turn_on_fin (struct lsquic_packet_out *,
238c51ce338SDmitri Tikhonov                   const struct parse_funcs *, const struct lsquic_stream *);
239c51ce338SDmitri Tikhonov
24050aadb33SDmitri Tikhonov#endif
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