/* Copyright (c) 2017 - 2021 LiteSpeed Technologies Inc. See LICENSE. */ #ifndef LSQUIC_PARSE_H #define LSQUIC_PARSE_H 1 #include #include "lsquic_packet_common.h" #include "lsquic_packet_gquic.h" #include "lsquic_shared_support.h" struct lsquic_conn; struct lsquic_packet_in; struct lsquic_packet_out; struct packin_parse_state; struct stream_frame; struct lsquic_cid; enum packet_out_flags; enum lsquic_version; enum stream_dir; struct ack_info { enum packnum_space pns; enum { AI_ECN = 1 << 0, /* ecn_counts[1,2,3] contain ECN counts */ AI_TRUNCATED = 1 << 1, /* There were more ranges to parse, but we * ran out of elements in `ranges'. */ } flags; unsigned n_ranges; /* This is at least 1 */ /* Largest acked is ack_info.ranges[0].high */ lsquic_time_t lack_delta; uint64_t ecn_counts[4]; struct lsquic_packno_range ranges[256]; }; #define largest_acked(acki) (+(acki)->ranges[0].high) #define smallest_acked(acki) (+(acki)->ranges[(acki)->n_ranges - 1].low) /* Chrome may send an empty ACK frame when it closes a connection. * We do not know why it occurs -- perhaps a bug in Chrome. */ /* This macro cannot be used in IETF QUIC as zero is a valid packet number. * Hopefully the Chrome bug will have been fixed by then. */ #define empty_ack_frame(acki) (largest_acked(acki) == 0) /* gaf_: generate ACK frame */ struct lsquic_packno_range; typedef const struct lsquic_packno_range * (*gaf_rechist_first_f) (void *rechist); typedef const struct lsquic_packno_range * (*gaf_rechist_next_f) (void *rechist); typedef lsquic_time_t (*gaf_rechist_largest_recv_f) (void *rechist); /* gsf_: generate stream frame */ typedef size_t (*gsf_read_f) (void *stream, void *buf, size_t len, int *fin); /* This structure contains functions that parse and generate packets and * frames in version-specific manner. To begin with, there is difference * between GQUIC's little-endian (Q038 and lower) and big-endian formats * (Q039 and higher). Q046 and higher uses different format for packet headers. */ struct parse_funcs { /* Return buf length */ int (*pf_gen_reg_pkt_header) (const struct lsquic_conn *, const struct lsquic_packet_out *, unsigned char *, size_t, /* In Q050 and IETF QUIC, these are set: */ unsigned *packno_off, unsigned *packno_len); void (*pf_parse_packet_in_finish) (struct lsquic_packet_in *packet_in, struct packin_parse_state *); enum quic_frame_type (*pf_parse_frame_type) (const unsigned char *, size_t); /* Return used buffer length or a negative value if there was not enough * room to write the stream frame. In the latter case, the negative of * the negative return value is the number of bytes required. The * exception is -1, which is a generic error code, as we always need * more than 1 byte to write a STREAM frame. */ /* pf_gen_stream_frame and pf_gen_crypto_frame must be adjacent so that * they can be cast to an array. */ int (*pf_gen_stream_frame) (unsigned char *buf, size_t bufsz, lsquic_stream_id_t stream_id, uint64_t offset, int fin, size_t size, gsf_read_f, void *stream); /* The two "UNUSED" parameters are here so that it matches * pf_gen_stream_frame. */ int (*pf_gen_crypto_frame) (unsigned char *buf, size_t bufsz, lsquic_stream_id_t UNUSED_1, uint64_t offset, int UNUSED_2, size_t size, gsf_read_f, void *stream); /* pf_parse_stream_frame and pf_parse_crypto_frame must be adjacent so that * they can be cast to an array. */ int (*pf_parse_stream_frame) (const unsigned char *buf, size_t rem_packet_sz, struct stream_frame *); int (*pf_parse_crypto_frame) (const unsigned char *buf, size_t rem_packet_sz, struct stream_frame *); /* Return true if STREAM frame extends to the end of the packet and thus * does not contain a Length field (no update). */ int (*pf_dec_stream_frame_size) (unsigned char *buf, size_t new_size); int (*pf_parse_ack_frame) (const unsigned char *buf, size_t buf_len, struct ack_info *ack_info, uint8_t exp); int (*pf_gen_ack_frame) (unsigned char *outbuf, size_t outbuf_sz, gaf_rechist_first_f, gaf_rechist_next_f, gaf_rechist_largest_recv_f, void *rechist, lsquic_time_t now, int *has_missing, lsquic_packno_t *largest_received, const uint64_t *ecn_counts); int (*pf_gen_stop_waiting_frame) (unsigned char *buf, size_t buf_len, lsquic_packno_t cur_packno, enum packno_bits, lsquic_packno_t least_unacked_packno); int (*pf_parse_stop_waiting_frame) (const unsigned char *buf, size_t buf_len, lsquic_packno_t cur_packno, enum packno_bits, lsquic_packno_t *least_unacked); int (*pf_skip_stop_waiting_frame) (size_t buf_len, enum packno_bits); int (*pf_gen_window_update_frame) (unsigned char *buf, int buf_len, lsquic_stream_id_t stream_id, uint64_t offset); int (*pf_parse_window_update_frame) (const unsigned char *buf, size_t buf_len, lsquic_stream_id_t *stream_id, uint64_t *offset); /* The third argument for pf_gen_blocked_frame() and pf_parse_blocked_frame() * is Stream ID for GQUIC and offset for IETF QUIC. Since both of these are * uint64_t, we'll use the same function pointer. Just have to be a little * careful here. */ int (*pf_gen_blocked_frame) (unsigned char *buf, size_t buf_len, lsquic_stream_id_t stream_id); int (*pf_parse_blocked_frame) (const unsigned char *buf, size_t buf_len, /* TODO: rename third argument when dropping GQUIC */ lsquic_stream_id_t *stream_id); unsigned (*pf_blocked_frame_size) (uint64_t); unsigned (*pf_rst_frame_size) (lsquic_stream_id_t stream_id, uint64_t final_size, uint64_t error_code); int (*pf_gen_rst_frame) (unsigned char *buf, size_t buf_len, lsquic_stream_id_t stream_id, uint64_t offset, uint64_t error_code); int (*pf_parse_rst_frame) (const unsigned char *buf, size_t buf_len, lsquic_stream_id_t *stream_id, uint64_t *offset, uint64_t *error_code); int (*pf_parse_stop_sending_frame) (const unsigned char *buf, size_t buf_len, lsquic_stream_id_t *stream_id, uint64_t *error_code); unsigned (*pf_stop_sending_frame_size) (lsquic_stream_id_t, uint64_t); int (*pf_gen_stop_sending_frame) (unsigned char *buf, size_t buf_len, lsquic_stream_id_t, uint64_t error_code); size_t (*pf_connect_close_frame_size) (int app_error, unsigned error_code, unsigned frame_type, size_t reason_len); int (*pf_gen_connect_close_frame) (unsigned char *buf, size_t buf_len, int app_error, unsigned error_code, const char *reason, int reason_len); int (*pf_parse_connect_close_frame) (const unsigned char *buf, size_t buf_len, int *app_error, uint64_t *error_code, uint16_t *reason_length, uint8_t *reason_offset); int (*pf_gen_goaway_frame) (unsigned char *buf, size_t buf_len, uint32_t error_code, lsquic_stream_id_t last_good_stream_id, const char *reason, size_t reason_len); int (*pf_parse_goaway_frame) (const unsigned char *buf, size_t buf_len, uint32_t *error_code, lsquic_stream_id_t *last_good_stream_id, uint16_t *reason_length, const char **reason); int (*pf_gen_ping_frame) (unsigned char *buf, int buf_len); int (*pf_parse_path_chal_frame) (const unsigned char *buf, size_t, uint64_t *chal); int (*pf_parse_path_resp_frame) (const unsigned char *buf, size_t, uint64_t *resp); /* These float reading and writing functions assume `mem' has at least * 2 bytes. */ void (*pf_write_float_time16) (lsquic_time_t time_us, void *mem); uint64_t (*pf_read_float_time16) (const void *mem); ssize_t (*pf_generate_simple_prst) (const lsquic_cid_t *cid, unsigned char *, size_t); size_t (*pf_calc_stream_frame_header_sz) (lsquic_stream_id_t stream_id, uint64_t offset, unsigned data_sz); size_t (*pf_calc_crypto_frame_header_sz) (uint64_t offset, unsigned data_sz); void (*pf_turn_on_fin) (unsigned char *); size_t (*pf_packout_size) (const struct lsquic_conn *, const struct lsquic_packet_out *); /* This returns the high estimate of the header size. Note that it * cannot account for the size of the token in the IETF QUIC Initial * packets as it does not know it. */ size_t (*pf_packout_max_header_size) (const struct lsquic_conn *, enum packet_out_flags, size_t dcid_len, enum header_type); enum packno_bits (*pf_calc_packno_bits) (lsquic_packno_t packno, lsquic_packno_t least_unacked, uint64_t n_in_flight); unsigned (*pf_packno_bits2len) (enum packno_bits); int (*pf_parse_max_data) (const unsigned char *, size_t, uint64_t *); int (*pf_gen_max_data_frame) (unsigned char *, size_t, uint64_t); unsigned (*pf_max_data_frame_size) (uint64_t); /* * Returns number of bytes parsed on success or negative value on error: * -1 Out of input buffer * -2 Invalid CID length value */ int (*pf_parse_new_conn_id) (const unsigned char *, size_t, uint64_t *, uint64_t *, lsquic_cid_t *, const unsigned char **); unsigned (*pf_stream_blocked_frame_size) (lsquic_stream_id_t, uint64_t); int (*pf_gen_stream_blocked_frame) (unsigned char *buf, size_t, lsquic_stream_id_t, uint64_t); int (*pf_parse_stream_blocked_frame) (const unsigned char *buf, size_t, lsquic_stream_id_t *, uint64_t *); unsigned (*pf_max_stream_data_frame_size) (lsquic_stream_id_t, uint64_t); int (*pf_gen_max_stream_data_frame) (unsigned char *buf, size_t, lsquic_stream_id_t, uint64_t); int (*pf_parse_max_stream_data_frame) (const unsigned char *buf, size_t, lsquic_stream_id_t *, uint64_t *); int (*pf_parse_new_token_frame) (const unsigned char *buf, size_t, const unsigned char **token, size_t *token_size); size_t (*pf_new_connection_id_frame_size) (unsigned seqno, unsigned cid_len); int (*pf_gen_new_connection_id_frame) (unsigned char *buf, size_t, unsigned seqno, const struct lsquic_cid *, const unsigned char *token, size_t); size_t (*pf_retire_cid_frame_size) (uint64_t); int (*pf_gen_retire_cid_frame) (unsigned char *buf, size_t, uint64_t); int (*pf_parse_retire_cid_frame) (const unsigned char *buf, size_t, uint64_t *); size_t (*pf_new_token_frame_size) (size_t); int (*pf_gen_new_token_frame) (unsigned char *buf, size_t, const unsigned char *token, size_t); int (*pf_gen_streams_blocked_frame) (unsigned char *buf, size_t buf_len, enum stream_dir, uint64_t); int (*pf_parse_streams_blocked_frame) (const unsigned char *buf, size_t buf_len, enum stream_dir *, uint64_t *); unsigned (*pf_streams_blocked_frame_size) (uint64_t); int (*pf_gen_max_streams_frame) (unsigned char *buf, size_t buf_len, enum stream_dir, uint64_t); int (*pf_parse_max_streams_frame) (const unsigned char *buf, size_t buf_len, enum stream_dir *, uint64_t *); unsigned (*pf_max_streams_frame_size) (uint64_t); unsigned (*pf_path_chal_frame_size) (void); int (*pf_gen_path_chal_frame) (unsigned char *, size_t, uint64_t chal); unsigned (*pf_path_resp_frame_size) (void); int (*pf_gen_path_resp_frame) (unsigned char *, size_t, uint64_t resp); int (*pf_gen_handshake_done_frame) (unsigned char *buf, size_t buf_len); int (*pf_parse_handshake_done_frame) (const unsigned char *buf, size_t buf_len); unsigned (*pf_handshake_done_frame_size) (void); int (*pf_gen_ack_frequency_frame) (unsigned char *buf, size_t buf_len, uint64_t seqno, uint64_t pack_tol, uint64_t upd_mad, int ignore); int (*pf_parse_ack_frequency_frame) (const unsigned char *buf, size_t buf_len, uint64_t *seqno, uint64_t *pack_tol, uint64_t *upd_mad, int *ignore); unsigned (*pf_ack_frequency_frame_size) (uint64_t seqno, uint64_t pack_tol, uint64_t upd_mad /* Don't need to pass `ignore' */); int (*pf_gen_timestamp_frame) (unsigned char *buf, size_t buf_len, uint64_t); int (*pf_parse_timestamp_frame) (const unsigned char *buf, size_t, uint64_t *); int (*pf_parse_datagram_frame) (const unsigned char *buf, size_t, const void **, size_t *); int (*pf_gen_datagram_frame) (unsigned char *, size_t bufsz, size_t min_sz, size_t max_sz, ssize_t (*)(struct lsquic_conn *, void *, size_t), struct lsquic_conn *); unsigned (*pf_datagram_frame_size) (size_t); }; LSQUIC_EXTERN const struct parse_funcs lsquic_parse_funcs_gquic_Q043; LSQUIC_EXTERN const struct parse_funcs lsquic_parse_funcs_gquic_Q046; LSQUIC_EXTERN const struct parse_funcs lsquic_parse_funcs_gquic_Q050; LSQUIC_EXTERN const struct parse_funcs lsquic_parse_funcs_ietf_v1; #define select_pf_by_ver(ver) ( \ (1 << (ver)) & (1 << LSQVER_043) ? \ &lsquic_parse_funcs_gquic_Q043 : \ (1 << (ver)) & (1 << LSQVER_046) ? \ &lsquic_parse_funcs_gquic_Q046 : \ (1 << (ver)) & (1 << LSQVER_050) ? \ &lsquic_parse_funcs_gquic_Q050 : \ &lsquic_parse_funcs_ietf_v1) /* This function is gQUIC-version independent */ int lsquic_gquic_parse_packet_in_begin (struct lsquic_packet_in *, size_t length, int is_server, unsigned cid_len, struct packin_parse_state *); int lsquic_Q046_parse_packet_in_short_begin (struct lsquic_packet_in *, size_t length, int is_server, unsigned, struct packin_parse_state *); int lsquic_Q046_parse_packet_in_long_begin (struct lsquic_packet_in *, size_t length, int is_server, unsigned, struct packin_parse_state *); int lsquic_Q050_parse_packet_in_long_begin (struct lsquic_packet_in *, size_t length, int is_server, unsigned, struct packin_parse_state *); enum quic_frame_type lsquic_parse_frame_type_gquic_Q035_thru_Q046 (const unsigned char *, size_t); extern const enum quic_frame_type lsquic_iquic_byte2type[0x40]; size_t lsquic_calc_stream_frame_header_sz_gquic (lsquic_stream_id_t stream_id, uint64_t offset, unsigned); size_t lsquic_gquic_packout_size (const struct lsquic_conn *, const struct lsquic_packet_out *); size_t lsquic_gquic_packout_header_size (const struct lsquic_conn *conn, enum packet_out_flags flags, size_t unused, enum header_type); size_t lsquic_gquic_po_header_sz (enum packet_out_flags flags); size_t lsquic_gquic_packout_size (const struct lsquic_conn *, const struct lsquic_packet_out *); size_t lsquic_gquic_po_header_sz (enum packet_out_flags flags); /* This maps two bits as follows: * 00 -> 1 * 01 -> 2 * 10 -> 4 * 11 -> 6 * * Assumes that only two low bits are set. */ #define twobit_to_1246(bits) ((bits) * 2 + !(bits)) /* This maps two bits as follows: * 00 -> 1 * 01 -> 2 * 10 -> 4 * 11 -> 8 * * Assumes that only two low bits are set. */ #define twobit_to_1248(bits) (1 << (bits)) #define ECN_COUNTS_STR " ECT(0): 01234567879012345678790;" \ " ECT(1): 01234567879012345678790;" \ " CE: 01234567879012345678790" #define RANGES_TRUNCATED_STR " ranges truncated! " #define MAX_ACKI_STR_SZ (256 * (3 /* [-] */ + 20 /* ~0ULL */ * 2) \ + sizeof(ECN_COUNTS_STR) + sizeof(RANGES_TRUNCATED_STR)) void lsquic_acki2str (const struct ack_info *acki, char *, size_t); void lsquic_turn_on_fin_Q035_thru_Q046 (unsigned char *); enum packno_bits lsquic_gquic_calc_packno_bits (lsquic_packno_t packno, lsquic_packno_t least_unacked, uint64_t n_in_flight); unsigned lsquic_gquic_packno_bits2len (enum packno_bits); int lsquic_merge_acks (struct ack_info *dst, const struct ack_info *src); #endif