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| -rw-r--r-- | lib/ngtcp2_conn.h | 1115 |
1 files changed, 1115 insertions, 0 deletions
diff --git a/lib/ngtcp2_conn.h b/lib/ngtcp2_conn.h new file mode 100644 index 0000000..aef2380 --- /dev/null +++ b/lib/ngtcp2_conn.h @@ -0,0 +1,1115 @@ +/* + * ngtcp2 + * + * Copyright (c) 2017 ngtcp2 contributors + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION + * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +#ifndef NGTCP2_CONN_H +#define NGTCP2_CONN_H + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif /* HAVE_CONFIG_H */ + +#include <ngtcp2/ngtcp2.h> + +#include "ngtcp2_mem.h" +#include "ngtcp2_crypto.h" +#include "ngtcp2_acktr.h" +#include "ngtcp2_rtb.h" +#include "ngtcp2_strm.h" +#include "ngtcp2_idtr.h" +#include "ngtcp2_str.h" +#include "ngtcp2_pkt.h" +#include "ngtcp2_log.h" +#include "ngtcp2_pq.h" +#include "ngtcp2_cc.h" +#include "ngtcp2_bbr.h" +#include "ngtcp2_bbr2.h" +#include "ngtcp2_pv.h" +#include "ngtcp2_pmtud.h" +#include "ngtcp2_cid.h" +#include "ngtcp2_buf.h" +#include "ngtcp2_ppe.h" +#include "ngtcp2_qlog.h" +#include "ngtcp2_rst.h" + +typedef enum { + /* Client specific handshake states */ + NGTCP2_CS_CLIENT_INITIAL, + NGTCP2_CS_CLIENT_WAIT_HANDSHAKE, + NGTCP2_CS_CLIENT_TLS_HANDSHAKE_FAILED, + /* Server specific handshake states */ + NGTCP2_CS_SERVER_INITIAL, + NGTCP2_CS_SERVER_WAIT_HANDSHAKE, + NGTCP2_CS_SERVER_TLS_HANDSHAKE_FAILED, + /* Shared by both client and server */ + NGTCP2_CS_POST_HANDSHAKE, + NGTCP2_CS_CLOSING, + NGTCP2_CS_DRAINING, +} ngtcp2_conn_state; + +/* NGTCP2_MAX_STREAMS is the maximum number of streams. */ +#define NGTCP2_MAX_STREAMS (1LL << 60) + +/* NGTCP2_MAX_NUM_BUFFED_RX_PKTS is the maximum number of buffered + reordered packets. */ +#define NGTCP2_MAX_NUM_BUFFED_RX_PKTS 4 + +/* NGTCP2_MAX_REORDERED_CRYPTO_DATA is the maximum offset of crypto + data which is not continuous. In other words, there is a gap of + unreceived data. */ +#define NGTCP2_MAX_REORDERED_CRYPTO_DATA 65536 + +/* NGTCP2_MAX_RX_INITIAL_CRYPTO_DATA is the maximum offset of received + crypto stream in Initial packet. We set this hard limit here + because crypto stream is unbounded. */ +#define NGTCP2_MAX_RX_INITIAL_CRYPTO_DATA 65536 +/* NGTCP2_MAX_RX_HANDSHAKE_CRYPTO_DATA is the maximum offset of + received crypto stream in Handshake packet. We set this hard limit + here because crypto stream is unbounded. */ +#define NGTCP2_MAX_RX_HANDSHAKE_CRYPTO_DATA 65536 + +/* NGTCP2_MAX_RETRIES is the number of Retry packet which client can + accept. */ +#define NGTCP2_MAX_RETRIES 3 + +/* NGTCP2_MAX_BOUND_DCID_POOL_SIZE is the maximum number of + destination connection ID which have been bound to a particular + path, but not yet used as primary path and path validation is not + performed from the local endpoint. */ +#define NGTCP2_MAX_BOUND_DCID_POOL_SIZE 4 +/* NGTCP2_MAX_DCID_POOL_SIZE is the maximum number of destination + connection ID the remote endpoint provides to store. It must be + the power of 2. */ +#define NGTCP2_MAX_DCID_POOL_SIZE 8 +/* NGTCP2_MAX_DCID_RETIRED_SIZE is the maximum number of retired DCID + kept to catch in-flight packet on retired path. */ +#define NGTCP2_MAX_DCID_RETIRED_SIZE 2 +/* NGTCP2_MAX_SCID_POOL_SIZE is the maximum number of source + connection ID the local endpoint provides to the remote endpoint. + The chosen value was described in old draft. Now a remote endpoint + tells the maximum value. The value can be quite large, and we have + to put the sane limit.*/ +#define NGTCP2_MAX_SCID_POOL_SIZE 8 + +/* NGTCP2_MAX_NON_ACK_TX_PKT is the maximum number of continuous non + ACK-eliciting packets. */ +#define NGTCP2_MAX_NON_ACK_TX_PKT 3 + +/* NGTCP2_ECN_MAX_NUM_VALIDATION_PKTS is the maximum number of ECN marked + packets sent in NGTCP2_ECN_STATE_TESTING period. */ +#define NGTCP2_ECN_MAX_NUM_VALIDATION_PKTS 10 + +/* NGTCP2_CONNECTION_CLOSE_ERROR_MAX_REASONLEN is the maximum length + of reason phrase to remember. If the received reason phrase is + longer than this value, it is truncated. */ +#define NGTCP2_CONNECTION_CLOSE_ERROR_MAX_REASONLEN 1024 + +/* NGTCP2_WRITE_PKT_FLAG_NONE indicates that no flag is set. */ +#define NGTCP2_WRITE_PKT_FLAG_NONE 0x00u +/* NGTCP2_WRITE_PKT_FLAG_REQUIRE_PADDING indicates that packet other + than Initial packet should be padded. Initial packet might be + padded based on QUIC requirement regardless of this flag. */ +#define NGTCP2_WRITE_PKT_FLAG_REQUIRE_PADDING 0x01u +/* NGTCP2_WRITE_PKT_FLAG_MORE indicates that more frames might come + and it should be encoded into the current packet. */ +#define NGTCP2_WRITE_PKT_FLAG_MORE 0x02u + +/* + * ngtcp2_max_frame is defined so that it covers the largest ACK + * frame. + */ +typedef union ngtcp2_max_frame { + ngtcp2_frame fr; + struct { + ngtcp2_ack ack; + /* ack includes 1 ngtcp2_ack_range. */ + ngtcp2_ack_range ranges[NGTCP2_MAX_ACK_RANGES - 1]; + } ackfr; +} ngtcp2_max_frame; + +typedef struct ngtcp2_path_challenge_entry { + ngtcp2_path_storage ps; + uint8_t data[8]; +} ngtcp2_path_challenge_entry; + +void ngtcp2_path_challenge_entry_init(ngtcp2_path_challenge_entry *pcent, + const ngtcp2_path *path, + const uint8_t *data); + +/* NGTCP2_CONN_FLAG_NONE indicates that no flag is set. */ +#define NGTCP2_CONN_FLAG_NONE 0x00u +/* NGTCP2_CONN_FLAG_HANDSHAKE_COMPLETED is set when TLS stack declares + that TLS handshake has completed. The condition of this + declaration varies between TLS implementations and this flag does + not indicate the completion of QUIC handshake. Some + implementations declare TLS handshake completion as server when + they write off Server Finished and before deriving application rx + secret. */ +#define NGTCP2_CONN_FLAG_HANDSHAKE_COMPLETED 0x01u +/* NGTCP2_CONN_FLAG_CONN_ID_NEGOTIATED is set if connection ID is + negotiated. This is only used for client. */ +#define NGTCP2_CONN_FLAG_CONN_ID_NEGOTIATED 0x02u +/* NGTCP2_CONN_FLAG_TRANSPORT_PARAM_RECVED is set if transport + parameters are received. */ +#define NGTCP2_CONN_FLAG_TRANSPORT_PARAM_RECVED 0x04u +/* NGTCP2_CONN_FLAG_LOCAL_TRANSPORT_PARAMS_COMMITTED is set when a + local transport parameters are applied. */ +#define NGTCP2_CONN_FLAG_LOCAL_TRANSPORT_PARAMS_COMMITTED 0x08u +/* NGTCP2_CONN_FLAG_RECV_RETRY is set when a client receives Retry + packet. */ +#define NGTCP2_CONN_FLAG_RECV_RETRY 0x10u +/* NGTCP2_CONN_FLAG_EARLY_DATA_REJECTED is set when 0-RTT packet is + rejected by a peer. */ +#define NGTCP2_CONN_FLAG_EARLY_DATA_REJECTED 0x20u +/* NGTCP2_CONN_FLAG_KEEP_ALIVE_CANCELLED is set when the expired + keep-alive timer has been cancelled. */ +#define NGTCP2_CONN_FLAG_KEEP_ALIVE_CANCELLED 0x40u +/* NGTCP2_CONN_FLAG_HANDSHAKE_CONFIRMED is set when an endpoint + confirmed completion of handshake. */ +#define NGTCP2_CONN_FLAG_HANDSHAKE_CONFIRMED 0x80u +/* NGTCP2_CONN_FLAG_HANDSHAKE_COMPLETED_HANDLED is set when the + library transitions its state to "post handshake". */ +#define NGTCP2_CONN_FLAG_HANDSHAKE_COMPLETED_HANDLED 0x0100u +/* NGTCP2_CONN_FLAG_HANDSHAKE_EARLY_RETRANSMIT is set when the early + handshake retransmission has done when server receives overlapping + Initial crypto data. */ +#define NGTCP2_CONN_FLAG_HANDSHAKE_EARLY_RETRANSMIT 0x0200u +/* NGTCP2_CONN_FLAG_CLEAR_FIXED_BIT indicates that the local endpoint + sends a QUIC packet without Fixed Bit set if a remote endpoint + supports Greasing QUIC Bit extension. */ +#define NGTCP2_CONN_FLAG_CLEAR_FIXED_BIT 0x0400u +/* NGTCP2_CONN_FLAG_KEY_UPDATE_NOT_CONFIRMED is set when key update is + not confirmed by the local endpoint. That is, it has not received + ACK frame which acknowledges packet which is encrypted with new + key. */ +#define NGTCP2_CONN_FLAG_KEY_UPDATE_NOT_CONFIRMED 0x0800u +/* NGTCP2_CONN_FLAG_PPE_PENDING is set when + NGTCP2_WRITE_STREAM_FLAG_MORE is used and the intermediate state of + ngtcp2_ppe is stored in pkt struct of ngtcp2_conn. */ +#define NGTCP2_CONN_FLAG_PPE_PENDING 0x1000u +/* NGTCP2_CONN_FLAG_RESTART_IDLE_TIMER_ON_WRITE is set when idle timer + should be restarted on next write. */ +#define NGTCP2_CONN_FLAG_RESTART_IDLE_TIMER_ON_WRITE 0x2000u +/* NGTCP2_CONN_FLAG_SERVER_ADDR_VERIFIED indicates that server as peer + verified client address. This flag is only used by client. */ +#define NGTCP2_CONN_FLAG_SERVER_ADDR_VERIFIED 0x4000u +/* NGTCP2_CONN_FLAG_EARLY_KEY_INSTALLED indicates that an early key is + installed. conn->early.ckm cannot be used for this purpose because + it might be discarded when a certain condition is met. */ +#define NGTCP2_CONN_FLAG_EARLY_KEY_INSTALLED 0x8000u +/* NGTCP2_CONN_FLAG_KEY_UPDATE_INITIATOR is set when the local + endpoint has initiated key update. */ +#define NGTCP2_CONN_FLAG_KEY_UPDATE_INITIATOR 0x10000u + +typedef struct ngtcp2_crypto_data { + ngtcp2_buf buf; + /* pkt_type is the type of packet to send data in buf. If it is 0, + it must be sent in Short packet. Otherwise, it is sent the long + packet type denoted by pkt_type. */ + uint8_t pkt_type; +} ngtcp2_crypto_data; + +typedef struct ngtcp2_pktns { + struct { + /* last_pkt_num is the packet number which the local endpoint sent + last time.*/ + int64_t last_pkt_num; + ngtcp2_frame_chain *frq; + /* num_non_ack_pkt is the number of continuous non ACK-eliciting + packets. */ + size_t num_non_ack_pkt; + + struct { + /* ect0 is the number of QUIC packets, not UDP datagram, which + are sent in UDP datagram with ECT0 marking. */ + size_t ect0; + /* start_pkt_num is the lowest packet number that are sent + during ECN validation period. */ + int64_t start_pkt_num; + /* validation_pkt_sent is the number of QUIC packets sent during + validation period. */ + size_t validation_pkt_sent; + /* validation_pkt_lost is the number of QUIC packets lost during + validation period. */ + size_t validation_pkt_lost; + } ecn; + } tx; + + struct { + /* pngap tracks received packet number in order to suppress + duplicated packet number. */ + ngtcp2_gaptr pngap; + /* max_pkt_num is the largest packet number received so far. */ + int64_t max_pkt_num; + /* max_pkt_ts is the timestamp when max_pkt_num packet is + received. */ + ngtcp2_tstamp max_pkt_ts; + /* max_ack_eliciting_pkt_num is the largest ack-eliciting packet + number received so far. */ + int64_t max_ack_eliciting_pkt_num; + /* + * buffed_pkts is buffered packets which cannot be decrypted with + * the current encryption level. + * + * In server Initial encryption level, 0-RTT packet may be buffered. + * In server Handshake encryption level, Short packet may be buffered. + * + * In client Initial encryption level, Handshake or Short packet may + * be buffered. In client Handshake encryption level, Short packet + * may be buffered. + * + * - 0-RTT packet is only buffered in server Initial encryption + * level ngtcp2_pktns. + * + * - Handshake packet is only buffered in client Handshake + * encryption level ngtcp2_pktns. + * + * - Short packet is only buffered in Short encryption level + * ngtcp2_pktns. + */ + ngtcp2_pkt_chain *buffed_pkts; + + struct { + /* ect0, ect1, and ce are the number of QUIC packets received + with those markings. */ + size_t ect0; + size_t ect1; + size_t ce; + struct { + /* ect0, ect1, ce are the ECN counts received in the latest + ACK frame. */ + uint64_t ect0; + uint64_t ect1; + uint64_t ce; + } ack; + } ecn; + } rx; + + struct { + struct { + /* frq contains crypto data sorted by their offset. */ + ngtcp2_ksl frq; + /* offset is the offset of crypto stream in this packet number + space. */ + uint64_t offset; + /* ckm is a cryptographic key, and iv to encrypt outgoing + packets. */ + ngtcp2_crypto_km *ckm; + /* hp_ctx is cipher context for packet header protection. */ + ngtcp2_crypto_cipher_ctx hp_ctx; + /* data is the submitted crypto data. */ + ngtcp2_buf_chain *data; + } tx; + + struct { + /* ckm is a cryptographic key, and iv to decrypt incoming + packets. */ + ngtcp2_crypto_km *ckm; + /* hp_ctx is cipher context for packet header protection. */ + ngtcp2_crypto_cipher_ctx hp_ctx; + } rx; + + ngtcp2_strm strm; + ngtcp2_crypto_ctx ctx; + } crypto; + + ngtcp2_acktr acktr; + ngtcp2_rtb rtb; +} ngtcp2_pktns; + +typedef enum ngtcp2_ecn_state { + NGTCP2_ECN_STATE_TESTING, + NGTCP2_ECN_STATE_UNKNOWN, + NGTCP2_ECN_STATE_FAILED, + NGTCP2_ECN_STATE_CAPABLE, +} ngtcp2_ecn_state; + +ngtcp2_static_ringbuf_def(dcid_bound, NGTCP2_MAX_BOUND_DCID_POOL_SIZE, + sizeof(ngtcp2_dcid)); +ngtcp2_static_ringbuf_def(dcid_unused, NGTCP2_MAX_DCID_POOL_SIZE, + sizeof(ngtcp2_dcid)); +ngtcp2_static_ringbuf_def(dcid_retired, NGTCP2_MAX_DCID_RETIRED_SIZE, + sizeof(ngtcp2_dcid)); +ngtcp2_static_ringbuf_def(path_challenge, 4, + sizeof(ngtcp2_path_challenge_entry)); + +ngtcp2_objalloc_def(strm, ngtcp2_strm, oplent); + +struct ngtcp2_conn { + ngtcp2_objalloc frc_objalloc; + ngtcp2_objalloc rtb_entry_objalloc; + ngtcp2_objalloc strm_objalloc; + ngtcp2_conn_state state; + ngtcp2_callbacks callbacks; + /* rcid is a connection ID present in Initial or 0-RTT packet from + client as destination connection ID. Server uses this field to + check that duplicated Initial or 0-RTT packet are indeed sent to + this connection. Client uses this field to validate + original_destination_connection_id transport parameter. */ + ngtcp2_cid rcid; + /* oscid is the source connection ID initially used by the local + endpoint. */ + ngtcp2_cid oscid; + /* retry_scid is the source connection ID from Retry packet. Client + records it in order to verify retry_source_connection_id + transport parameter. Server does not use this field. */ + ngtcp2_cid retry_scid; + ngtcp2_pktns *in_pktns; + ngtcp2_pktns *hs_pktns; + ngtcp2_pktns pktns; + + struct { + /* current is the current destination connection ID. */ + ngtcp2_dcid current; + /* bound is a set of destination connection IDs which are bound to + particular paths. These paths are not validated yet. */ + ngtcp2_static_ringbuf_dcid_bound bound; + /* unused is a set of unused CID received from peer. */ + ngtcp2_static_ringbuf_dcid_unused unused; + /* retired is a set of CID retired by local endpoint. Keep them + in 3*PTO to catch packets in flight along the old path. */ + ngtcp2_static_ringbuf_dcid_retired retired; + /* seqgap tracks received sequence numbers in order to ignore + retransmitted duplicated NEW_CONNECTION_ID frame. */ + ngtcp2_gaptr seqgap; + /* retire_prior_to is the largest retire_prior_to received so + far. */ + uint64_t retire_prior_to; + struct { + /* seqs contains sequence number of Connection ID whose + retirement is not acknowledged by the remote endpoint yet. */ + uint64_t seqs[NGTCP2_MAX_DCID_POOL_SIZE * 2]; + /* len is the number of sequence numbers that seq contains. */ + size_t len; + } retire_unacked; + /* zerolen_seq is a pseudo sequence number of zero-length + Destination Connection ID in order to distinguish between + them. */ + uint64_t zerolen_seq; + } dcid; + + struct { + /* set is a set of CID sent to peer. The peer can use any CIDs in + this set. This includes used CID as well as unused ones. */ + ngtcp2_ksl set; + /* used is a set of CID used by peer. The sort function of this + priority queue takes timestamp when CID is retired and sorts + them in ascending order. */ + ngtcp2_pq used; + /* last_seq is the last sequence number of connection ID. */ + uint64_t last_seq; + /* num_retired is the number of retired Connection ID still + included in set. */ + size_t num_retired; + } scid; + + struct { + /* strmq contains ngtcp2_strm which has frames to send. */ + ngtcp2_pq strmq; + /* strmq_nretrans is the number of entries in strmq which has + stream data to resent. */ + size_t strmq_nretrans; + /* ack is ACK frame. The underlying buffer is reused. */ + ngtcp2_frame *ack; + /* max_ack_ranges is the number of additional ngtcp2_ack_range + which ack can contain. */ + size_t max_ack_ranges; + /* offset is the offset the local endpoint has sent to the remote + endpoint. */ + uint64_t offset; + /* max_offset is the maximum offset that local endpoint can + send. */ + uint64_t max_offset; + /* last_max_data_ts is the timestamp when last MAX_DATA frame is + sent. */ + ngtcp2_tstamp last_max_data_ts; + + struct { + /* state is the state of ECN validation */ + ngtcp2_ecn_state state; + /* validation_start_ts is the timestamp when ECN validation is + started. It is UINT64_MAX if it has not started yet. */ + ngtcp2_tstamp validation_start_ts; + /* dgram_sent is the number of UDP datagram sent during ECN + validation period. */ + size_t dgram_sent; + } ecn; + + struct { + /* pktlen is the number of bytes written before calling + ngtcp2_conn_update_pkt_tx_time which resets this field to + 0. */ + size_t pktlen; + /* next_ts is the time to send next packet. It is UINT64_MAX if + packet pacing is disabled or expired.*/ + ngtcp2_tstamp next_ts; + } pacing; + } tx; + + struct { + /* unsent_max_offset is the maximum offset that remote endpoint + can send without extending MAX_DATA. This limit is not yet + notified to the remote endpoint. */ + uint64_t unsent_max_offset; + /* offset is the cumulative sum of stream data received for this + connection. */ + uint64_t offset; + /* max_offset is the maximum offset that remote endpoint can + send. */ + uint64_t max_offset; + /* window is the connection-level flow control window size. */ + uint64_t window; + /* path_challenge stores received PATH_CHALLENGE data. */ + ngtcp2_static_ringbuf_path_challenge path_challenge; + /* ccerr is the received connection close error. */ + ngtcp2_connection_close_error ccerr; + } rx; + + struct { + ngtcp2_crypto_km *ckm; + ngtcp2_crypto_cipher_ctx hp_ctx; + ngtcp2_crypto_ctx ctx; + /* discard_started_ts is the timestamp when the timer to discard + early key has started. Used by server only. */ + ngtcp2_tstamp discard_started_ts; + /* transport_params is the values remembered by client from the + previous session. These are set by + ngtcp2_conn_set_early_remote_transport_params(). Server does + not use this field. Server must not set values for these + parameters that are smaller than the remembered values. */ + struct { + uint64_t initial_max_streams_bidi; + uint64_t initial_max_streams_uni; + uint64_t initial_max_stream_data_bidi_local; + uint64_t initial_max_stream_data_bidi_remote; + uint64_t initial_max_stream_data_uni; + uint64_t initial_max_data; + uint64_t active_connection_id_limit; + uint64_t max_datagram_frame_size; + } transport_params; + } early; + + struct { + ngtcp2_settings settings; + /* transport_params is the local transport parameters. It is used + for Short packet only. */ + ngtcp2_transport_params transport_params; + struct { + /* max_streams is the maximum number of bidirectional streams which + the local endpoint can open. */ + uint64_t max_streams; + /* next_stream_id is the bidirectional stream ID which the local + endpoint opens next. */ + int64_t next_stream_id; + } bidi; + + struct { + /* max_streams is the maximum number of unidirectional streams + which the local endpoint can open. */ + uint64_t max_streams; + /* next_stream_id is the unidirectional stream ID which the + local endpoint opens next. */ + int64_t next_stream_id; + } uni; + } local; + + struct { + /* transport_params is the received transport parameters during + handshake. It is used for Short packet only. */ + ngtcp2_transport_params *transport_params; + /* pending_transport_params is received transport parameters + during handshake. It is copied to transport_params when 1RTT + key is available. */ + ngtcp2_transport_params *pending_transport_params; + struct { + ngtcp2_idtr idtr; + /* unsent_max_streams is the maximum number of streams of peer + initiated bidirectional stream which the local endpoint can + accept. This limit is not yet notified to the remote + endpoint. */ + uint64_t unsent_max_streams; + /* max_streams is the maximum number of streams of peer + initiated bidirectional stream which the local endpoint can + accept. */ + uint64_t max_streams; + } bidi; + + struct { + ngtcp2_idtr idtr; + /* unsent_max_streams is the maximum number of streams of peer + initiated unidirectional stream which the local endpoint can + accept. This limit is not yet notified to the remote + endpoint. */ + uint64_t unsent_max_streams; + /* max_streams is the maximum number of streams of peer + initiated unidirectional stream which the local endpoint can + accept. */ + uint64_t max_streams; + } uni; + } remote; + + struct { + struct { + /* new_tx_ckm is a new sender 1RTT key which has not been + used. */ + ngtcp2_crypto_km *new_tx_ckm; + /* new_rx_ckm is a new receiver 1RTT key which has not + successfully decrypted incoming packet yet. */ + ngtcp2_crypto_km *new_rx_ckm; + /* old_rx_ckm is an old receiver 1RTT key. */ + ngtcp2_crypto_km *old_rx_ckm; + /* confirmed_ts is the time instant when the key update is + confirmed by the local endpoint last time. UINT64_MAX means + undefined value. */ + ngtcp2_tstamp confirmed_ts; + } key_update; + + /* tls_native_handle is a native handle to TLS session object. */ + void *tls_native_handle; + /* decrypt_hp_buf is a buffer which is used to write unprotected + packet header. */ + ngtcp2_vec decrypt_hp_buf; + /* decrypt_buf is a buffer which is used to write decrypted data. */ + ngtcp2_vec decrypt_buf; + /* retry_aead is AEAD to verify Retry packet integrity. It is + used by client only. */ + ngtcp2_crypto_aead retry_aead; + /* retry_aead_ctx is AEAD cipher context to verify Retry packet + integrity. It is used by client only. */ + ngtcp2_crypto_aead_ctx retry_aead_ctx; + /* tls_error is TLS related error. */ + int tls_error; + /* tls_alert is TLS alert generated by the local endpoint. */ + uint8_t tls_alert; + /* decryption_failure_count is the number of received packets that + fail authentication. */ + uint64_t decryption_failure_count; + } crypto; + + /* pkt contains the packet intermediate construction data to support + NGTCP2_WRITE_STREAM_FLAG_MORE */ + struct { + ngtcp2_crypto_cc cc; + ngtcp2_pkt_hd hd; + ngtcp2_ppe ppe; + ngtcp2_frame_chain **pfrc; + int pkt_empty; + int hd_logged; + /* flags is bitwise OR of zero or more of + NGTCP2_RTB_ENTRY_FLAG_*. */ + uint16_t rtb_entry_flags; + ngtcp2_ssize hs_spktlen; + int require_padding; + } pkt; + + struct { + /* last_ts is a timestamp when a last packet is sent or received + on a current path. */ + ngtcp2_tstamp last_ts; + /* timeout is keep-alive timeout. When it expires, a packet + should be sent to a current path to keep connection alive. It + might be used to keep NAT binding intact. If 0 is set, + keep-alive timer is disabled. */ + ngtcp2_duration timeout; + } keep_alive; + + struct { + /* Initial keys for negotiated version. If original version == + negotiated version, these fields are not used. */ + struct { + ngtcp2_crypto_km *ckm; + ngtcp2_crypto_cipher_ctx hp_ctx; + } rx; + struct { + ngtcp2_crypto_km *ckm; + ngtcp2_crypto_cipher_ctx hp_ctx; + } tx; + /* version is QUIC version that the above Initial keys are created + for. */ + uint32_t version; + /* preferred_versions is the array of versions that are preferred + by the local endpoint. Server negotiates one of those versions + in this array if a client initially selects a less preferred + version. Client uses this field and original_version field to + prevent version downgrade attack if it reacted upon Version + Negotiation packet. */ + uint32_t *preferred_versions; + /* preferred_versionslen is the number of versions stored in the + array pointed by preferred_versions. This field is only used + by server. */ + size_t preferred_versionslen; + /* other_versions is the versions that the local endpoint sends in + version_information transport parameter. This is the wire + image of other_versions field of version_information transport + parameter. */ + uint8_t *other_versions; + /* other_versionslen is the length of data pointed by + other_versions field. */ + size_t other_versionslen; + } vneg; + + ngtcp2_map strms; + ngtcp2_conn_stat cstat; + ngtcp2_pv *pv; + ngtcp2_pmtud *pmtud; + ngtcp2_log log; + ngtcp2_qlog qlog; + ngtcp2_rst rst; + ngtcp2_cc_algo cc_algo; + ngtcp2_cc cc; + const ngtcp2_mem *mem; + /* idle_ts is the time instant when idle timer started. */ + ngtcp2_tstamp idle_ts; + void *user_data; + uint32_t client_chosen_version; + uint32_t negotiated_version; + /* flags is bitwise OR of zero or more of NGTCP2_CONN_FLAG_*. */ + uint32_t flags; + int server; +}; + +typedef enum ngtcp2_vmsg_type { + NGTCP2_VMSG_TYPE_STREAM, + NGTCP2_VMSG_TYPE_DATAGRAM, +} ngtcp2_vmsg_type; + +typedef struct ngtcp2_vmsg_stream { + /* strm is a stream that data is sent to. */ + ngtcp2_strm *strm; + /* flags is bitwise OR of zero or more of + NGTCP2_WRITE_STREAM_FLAG_*. */ + uint32_t flags; + /* data is the pointer to ngtcp2_vec array which contains the stream + data to send. */ + const ngtcp2_vec *data; + /* datacnt is the number of ngtcp2_vec pointed by data. */ + size_t datacnt; + /* pdatalen is the pointer to the variable which the number of bytes + written is assigned to if pdatalen is not NULL. */ + ngtcp2_ssize *pdatalen; +} ngtcp2_vmsg_stream; + +typedef struct ngtcp2_vmsg_datagram { + /* data is the pointer to ngtcp2_vec array which contains the data + to send. */ + const ngtcp2_vec *data; + /* datacnt is the number of ngtcp2_vec pointed by data. */ + size_t datacnt; + /* dgram_id is an opaque identifier chosen by an application. */ + uint64_t dgram_id; + /* flags is bitwise OR of zero or more of + NGTCP2_WRITE_DATAGRAM_FLAG_*. */ + uint32_t flags; + /* paccepted is the pointer to the variable which, if it is not + NULL, is assigned nonzero if data is written to a packet. */ + int *paccepted; +} ngtcp2_vmsg_datagram; + +typedef struct ngtcp2_vmsg { + ngtcp2_vmsg_type type; + union { + ngtcp2_vmsg_stream stream; + ngtcp2_vmsg_datagram datagram; + }; +} ngtcp2_vmsg; + +/* + * ngtcp2_conn_sched_ack stores packet number |pkt_num| and its + * reception timestamp |ts| in order to send its ACK. + * + * It returns 0 if it succeeds, or one of the following negative error + * codes: + * + * NGTCP2_ERR_NOMEM + * Out of memory + * NGTCP2_ERR_PROTO + * Same packet number has already been added. + */ +int ngtcp2_conn_sched_ack(ngtcp2_conn *conn, ngtcp2_acktr *acktr, + int64_t pkt_num, int active_ack, ngtcp2_tstamp ts); + +/* + * ngtcp2_conn_find_stream returns a stream whose stream ID is + * |stream_id|. If no such stream is found, it returns NULL. + */ +ngtcp2_strm *ngtcp2_conn_find_stream(ngtcp2_conn *conn, int64_t stream_id); + +/* + * conn_init_stream initializes |strm|. Its stream ID is |stream_id|. + * This function adds |strm| to conn->strms. |strm| must be allocated + * by the caller. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_NOMEM + * Out of memory + * NGTCP2_ERR_CALLBACK_FAILURE + * User-callback function failed. + */ +int ngtcp2_conn_init_stream(ngtcp2_conn *conn, ngtcp2_strm *strm, + int64_t stream_id, void *stream_user_data); + +/* + * ngtcp2_conn_close_stream closes stream |strm|. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_INVALID_ARGUMENT + * Stream is not found. + * NGTCP2_ERR_CALLBACK_FAILURE + * User-defined callback function failed. + */ +int ngtcp2_conn_close_stream(ngtcp2_conn *conn, ngtcp2_strm *strm); + +/* + * ngtcp2_conn_close_stream closes stream |strm| if no further + * transmission and reception are allowed, and all reordered incoming + * data are emitted to the application, and the transmitted data are + * acked. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_INVALID_ARGUMENT + * Stream is not found. + * NGTCP2_ERR_CALLBACK_FAILURE + * User-defined callback function failed. + */ +int ngtcp2_conn_close_stream_if_shut_rdwr(ngtcp2_conn *conn, ngtcp2_strm *strm); + +/* + * ngtcp2_conn_update_rtt updates RTT measurements. |rtt| is a latest + * RTT which is not adjusted by ack delay. |ack_delay| is unscaled + * ack_delay included in ACK frame. |ack_delay| is actually tainted + * (sent by peer), so don't assume that |ack_delay| is always smaller + * than, or equals to |rtt|. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_INVALID_ARGUMENT + * RTT sample is ignored. + */ +int ngtcp2_conn_update_rtt(ngtcp2_conn *conn, ngtcp2_duration rtt, + ngtcp2_duration ack_delay, ngtcp2_tstamp ts); + +void ngtcp2_conn_set_loss_detection_timer(ngtcp2_conn *conn, ngtcp2_tstamp ts); + +int ngtcp2_conn_on_loss_detection_timer(ngtcp2_conn *conn, ngtcp2_tstamp ts); + +/* + * ngtcp2_conn_detect_lost_pkt detects lost packets. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_NOMEM + * Out of memory. + */ +int ngtcp2_conn_detect_lost_pkt(ngtcp2_conn *conn, ngtcp2_pktns *pktns, + ngtcp2_conn_stat *cstat, ngtcp2_tstamp ts); + +/* + * ngtcp2_conn_tx_strmq_top returns the ngtcp2_strm which sits on the + * top of queue. tx_strmq must not be empty. + */ +ngtcp2_strm *ngtcp2_conn_tx_strmq_top(ngtcp2_conn *conn); + +/* + * ngtcp2_conn_tx_strmq_pop pops the ngtcp2_strm from the queue. + * tx_strmq must not be empty. + */ +void ngtcp2_conn_tx_strmq_pop(ngtcp2_conn *conn); + +/* + * ngtcp2_conn_tx_strmq_push pushes |strm| into tx_strmq. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_NOMEM + * Out of memory. + */ +int ngtcp2_conn_tx_strmq_push(ngtcp2_conn *conn, ngtcp2_strm *strm); + +/* + * ngtcp2_conn_internal_expiry returns the minimum expiry time among + * all timers in |conn|. + */ +ngtcp2_tstamp ngtcp2_conn_internal_expiry(ngtcp2_conn *conn); + +ngtcp2_ssize ngtcp2_conn_write_vmsg(ngtcp2_conn *conn, ngtcp2_path *path, + int pkt_info_version, ngtcp2_pkt_info *pi, + uint8_t *dest, size_t destlen, + ngtcp2_vmsg *vmsg, ngtcp2_tstamp ts); + +/* + * ngtcp2_conn_write_single_frame_pkt writes a packet which contains + * |fr| frame only in the buffer pointed by |dest| whose length if + * |destlen|. |type| is a long packet type to send. If |type| is 0, + * Short packet is used. |dcid| is used as a destination connection + * ID. |flags| is zero or more of NGTCP2_WRITE_PKT_FLAG_*. Only + * NGTCP2_WRITE_PKT_FLAG_REQUIRE_PADDING is recognized. + * + * The packet written by this function will not be retransmitted. + * + * This function returns the number of bytes written in |dest| if it + * succeeds, or one of the following negative error codes: + * + * NGTCP2_ERR_CALLBACK_FAILURE + * User-defined callback function failed. + */ +ngtcp2_ssize ngtcp2_conn_write_single_frame_pkt( + ngtcp2_conn *conn, ngtcp2_pkt_info *pi, uint8_t *dest, size_t destlen, + uint8_t type, uint8_t flags, const ngtcp2_cid *dcid, ngtcp2_frame *fr, + uint16_t rtb_entry_flags, const ngtcp2_path *path, ngtcp2_tstamp ts); + +/* + * ngtcp2_conn_commit_local_transport_params commits the local + * transport parameters, which is currently set to + * conn->local.settings.transport_params. This function will do some + * amends on transport parameters for adjusting default values. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_NOMEM + * Out of memory. + * NGTCP2_ERR_INVALID_ARGUMENT + * CID in preferred address equals to the original SCID. + */ +int ngtcp2_conn_commit_local_transport_params(ngtcp2_conn *conn); + +/* + * ngtcp2_conn_lost_pkt_expiry returns the earliest expiry time of + * lost packet. + */ +ngtcp2_tstamp ngtcp2_conn_lost_pkt_expiry(ngtcp2_conn *conn); + +/* + * ngtcp2_conn_remove_lost_pkt removes the expired lost packet. + */ +void ngtcp2_conn_remove_lost_pkt(ngtcp2_conn *conn, ngtcp2_tstamp ts); + +/* + * ngtcp2_conn_resched_frames reschedules frames linked from |*pfrc| + * for retransmission. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_NOMEM + * Out of memory. + */ +int ngtcp2_conn_resched_frames(ngtcp2_conn *conn, ngtcp2_pktns *pktns, + ngtcp2_frame_chain **pfrc); + +uint64_t ngtcp2_conn_tx_strmq_first_cycle(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_ack_delay_expiry` returns the expiry time point of + * delayed protected ACK. One should call + * `ngtcp2_conn_cancel_expired_ack_delay_timer` and + * `ngtcp2_conn_write_pkt` (or `ngtcp2_conn_writev_stream`) when it + * expires. It returns UINT64_MAX if there is no expiry. + */ +ngtcp2_tstamp ngtcp2_conn_ack_delay_expiry(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_cancel_expired_ack_delay_timer` stops expired ACK + * delay timer. |ts| is the current time. This function must be + * called when `ngtcp2_conn_ack_delay_expiry` <= ts. + */ +void ngtcp2_conn_cancel_expired_ack_delay_timer(ngtcp2_conn *conn, + ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_loss_detection_expiry` returns the expiry time point + * of loss detection timer. One should call + * `ngtcp2_conn_on_loss_detection_timer` and `ngtcp2_conn_write_pkt` + * (or `ngtcp2_conn_writev_stream`) when it expires. It returns + * UINT64_MAX if loss detection timer is not armed. + */ +ngtcp2_tstamp ngtcp2_conn_loss_detection_expiry(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_idle_expiry` returns the time when a connection + * should be closed if it continues to be idle. If idle timeout is + * disabled, this function returns ``UINT64_MAX``. + */ +ngtcp2_tstamp ngtcp2_conn_get_idle_expiry(ngtcp2_conn *conn); + +ngtcp2_duration ngtcp2_conn_compute_pto(ngtcp2_conn *conn, ngtcp2_pktns *pktns); + +/* + * ngtcp2_conn_track_retired_dcid_seq tracks the sequence number |seq| + * of unacknowledged retiring Destination Connection ID. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * NGTCP2_ERR_CONNECTION_ID_LIMIT + * The number of unacknowledged retirement exceeds the limit. + */ +int ngtcp2_conn_track_retired_dcid_seq(ngtcp2_conn *conn, uint64_t seq); + +/* + * ngtcp2_conn_untrack_retired_dcid_seq deletes the sequence number + * |seq| of unacknowledged retiring Destination Connection ID. It is + * fine if such sequence number is not found. + */ +void ngtcp2_conn_untrack_retired_dcid_seq(ngtcp2_conn *conn, uint64_t seq); + +/* + * ngtcp2_conn_server_negotiate_version negotiates QUIC version. It + * is compatible version negotiation. It returns the negotiated QUIC + * version. This function must not be called by client. + */ +uint32_t +ngtcp2_conn_server_negotiate_version(ngtcp2_conn *conn, + const ngtcp2_version_info *version_info); + +/** + * @function + * + * `ngtcp2_conn_write_connection_close_pkt` writes a packet which + * contains a CONNECTION_CLOSE frame (type 0x1c) in the buffer pointed + * by |dest| whose capacity is |datalen|. + * + * If |path| is not ``NULL``, this function stores the network path + * with which the packet should be sent. Each addr field must point + * to the buffer which should be at least ``sizeof(struct + * sockaddr_storage)`` bytes long. The assignment might not be done + * if nothing is written to |dest|. + * + * If |pi| is not ``NULL``, this function stores packet metadata in it + * if it succeeds. The metadata includes ECN markings. + * + * This function must not be called from inside the callback + * functions. + * + * At the moment, successful call to this function makes connection + * close. We may change this behaviour in the future to allow + * graceful shutdown. + * + * This function returns the number of bytes written in |dest| if it + * succeeds, or one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small + * :macro:`NGTCP2_ERR_INVALID_STATE` + * The current state does not allow sending CONNECTION_CLOSE. + * :macro:`NGTCP2_ERR_PKT_NUM_EXHAUSTED` + * Packet number is exhausted, and cannot send any more packet. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * User callback failed + */ +ngtcp2_ssize ngtcp2_conn_write_connection_close_pkt( + ngtcp2_conn *conn, ngtcp2_path *path, ngtcp2_pkt_info *pi, uint8_t *dest, + size_t destlen, uint64_t error_code, const uint8_t *reason, + size_t reasonlen, ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_write_application_close_pkt` writes a packet which + * contains a CONNECTION_CLOSE frame (type 0x1d) in the buffer pointed + * by |dest| whose capacity is |datalen|. + * + * If |path| is not ``NULL``, this function stores the network path + * with which the packet should be sent. Each addr field must point + * to the buffer which should be at least ``sizeof(struct + * sockaddr_storage)`` bytes long. The assignment might not be done + * if nothing is written to |dest|. + * + * If |pi| is not ``NULL``, this function stores packet metadata in it + * if it succeeds. The metadata includes ECN markings. + * + * If handshake has not been confirmed yet, CONNECTION_CLOSE (type + * 0x1c) with error code :macro:`NGTCP2_APPLICATION_ERROR` is written + * instead. + * + * This function must not be called from inside the callback + * functions. + * + * At the moment, successful call to this function makes connection + * close. We may change this behaviour in the future to allow + * graceful shutdown. + * + * This function returns the number of bytes written in |dest| if it + * succeeds, or one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small + * :macro:`NGTCP2_ERR_INVALID_STATE` + * The current state does not allow sending CONNECTION_CLOSE. + * :macro:`NGTCP2_ERR_PKT_NUM_EXHAUSTED` + * Packet number is exhausted, and cannot send any more packet. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * User callback failed + */ +ngtcp2_ssize ngtcp2_conn_write_application_close_pkt( + ngtcp2_conn *conn, ngtcp2_path *path, ngtcp2_pkt_info *pi, uint8_t *dest, + size_t destlen, uint64_t app_error_code, const uint8_t *reason, + size_t reasonlen, ngtcp2_tstamp ts); + +int ngtcp2_conn_start_pmtud(ngtcp2_conn *conn); + +void ngtcp2_conn_stop_pmtud(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_remote_transport_params` sets transport parameter + * |params| from a remote endpoint to |conn|. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_TRANSPORT_PARAM` + * Failed to validate a remote transport parameters. + * :macro:`NGTCP2_ERR_VERSION_NEGOTIATION_FAILURE` + * Version negotiation failure. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * User callback failed + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +int ngtcp2_conn_set_remote_transport_params( + ngtcp2_conn *conn, const ngtcp2_transport_params *params); + +#endif /* NGTCP2_CONN_H */ |