1 #ifndef OSSL_QUIC_CHANNEL_LOCAL_H
2 # define OSSL_QUIC_CHANNEL_LOCAL_H
4 # include "internal/quic_channel.h"
6 # ifndef OPENSSL_NO_QUIC
9 * QUIC Channel Structure
10 * ======================
12 * QUIC channel internals. It is intended that only the QUIC_CHANNEL
13 * implementation and the RX depacketiser be allowed to access this structure
14 * directly. As the RX depacketiser has no state of its own and computes over a
15 * QUIC_CHANNEL structure, it can be viewed as an extention of the QUIC_CHANNEL
16 * implementation. While the RX depacketiser could be provided with adequate
17 * accessors to do what it needs, this would weaken the abstraction provided by
18 * the QUIC_CHANNEL to other components; moreover the coupling of the RX
19 * depacketiser to QUIC_CHANNEL internals is too deep and bespoke to make this
22 * Other components should not include this header.
24 struct quic_channel_st {
29 * Master synchronisation mutex used for thread assisted mode
30 * synchronisation. We don't own this; the instantiator of the channel
31 * passes it to us and is responsible for freeing it after channel
37 * Callback used to get the current time.
39 OSSL_TIME (*now_cb)(void *arg);
43 * The associated TLS 1.3 connection data. Used to provide the handshake
44 * layer; its 'network' side is plugged into the crypto stream for each EL
45 * (other than the 0-RTT EL).
51 * The transport parameter block we will send or have sent.
52 * Freed after sending or when connection is freed.
54 unsigned char *local_transport_params;
56 /* Asynchronous I/O reactor. */
59 /* Our current L4 peer address, if any. */
60 BIO_ADDR cur_peer_addr;
62 /* Network-side read and write BIOs. */
63 BIO *net_rbio, *net_wbio;
66 * Subcomponents of the connection. All of these components are instantiated
69 OSSL_QUIC_TX_PACKETISER *txp;
72 /* Connection level FC. */
77 OSSL_CC_DATA *cc_data;
78 const OSSL_CC_METHOD *cc_method;
82 * RX demuxer. We register incoming DCIDs with this. Since we currently only
83 * support client operation and use one L4 port per connection, we own the
84 * demuxer and register a single zero-length DCID with it.
88 /* Record layers in the TX and RX directions, plus the RX demuxer. */
93 * Send and receive parts of the crypto streams.
94 * crypto_send[QUIC_PN_SPACE_APP] is the 1-RTT crypto stream. There is no
95 * 0-RTT crypto stream.
97 QUIC_SSTREAM *crypto_send[QUIC_PN_SPACE_NUM];
98 QUIC_RSTREAM *crypto_recv[QUIC_PN_SPACE_NUM];
100 /* Internal state. */
102 * Client: The DCID used in the first Initial packet we transmit as a client.
103 * Server: The DCID used in the first Initial packet the client transmitted.
104 * Randomly generated and required by RFC to be at least 8 bytes.
106 QUIC_CONN_ID init_dcid;
109 * Client: The SCID found in the first Initial packet from the server.
110 * Not valid for servers.
111 * Valid if have_received_enc_pkt is set.
113 QUIC_CONN_ID init_scid;
116 * Client only: The SCID found in an incoming Retry packet we handled.
117 * Not valid for servers.
119 QUIC_CONN_ID retry_scid;
121 /* Server only: The DCID we currently use to talk to the peer. */
122 QUIC_CONN_ID cur_remote_dcid;
123 /* Server only: The DCID we currently expect the peer to use to talk to us. */
124 QUIC_CONN_ID cur_local_dcid;
126 /* Transport parameter values received from server. */
127 uint64_t rx_init_max_stream_data_bidi_local;
128 uint64_t rx_init_max_stream_data_bidi_remote;
129 uint64_t rx_init_max_stream_data_uni_remote;
130 uint64_t rx_max_ack_delay; /* ms */
131 unsigned char rx_ack_delay_exp;
134 * Temporary staging area to store information about the incoming packet we
135 * are currently processing.
137 OSSL_QRX_PKT *qrx_pkt;
140 * Current limit on number of streams we may create. Set by transport
141 * parameters initially and then by MAX_STREAMS frames.
143 uint64_t max_local_streams_bidi;
144 uint64_t max_local_streams_uni;
146 /* The negotiated maximum idle timeout in milliseconds. */
147 uint64_t max_idle_timeout;
150 * Maximum payload size in bytes for datagrams sent to our peer, as
151 * negotiated by transport parameters.
153 uint64_t rx_max_udp_payload_size;
154 /* Maximum active CID limit, as negotiated by transport parameters. */
155 uint64_t rx_active_conn_id_limit;
157 /* Valid if we are in the TERMINATING or TERMINATED states. */
158 QUIC_TERMINATE_CAUSE terminate_cause;
161 * Deadline at which we move to TERMINATING state. Valid if in the
164 OSSL_TIME terminate_deadline;
167 * Deadline at which connection dies due to idle timeout if no further
170 OSSL_TIME idle_deadline;
173 * Deadline at which we should send an ACK-eliciting packet to ensure
174 * idle timeout does not occur.
176 OSSL_TIME ping_deadline;
179 * State tracking. QUIC connection-level state is best represented based on
180 * whether various things have happened yet or not, rather than as an
181 * explicit FSM. We do have a coarse state variable which tracks the basic
182 * state of the connection's lifecycle, but more fine-grained conditions of
183 * the Active state are tracked via flags below. For more details, see
184 * doc/designs/quic-design/connection-state-machine.md. We are in the Open
185 * state if the state is QUIC_CSM_STATE_ACTIVE and handshake_confirmed is
188 unsigned int state : 3;
191 * Have we received at least one encrypted packet from the peer?
192 * (If so, Retry and Version Negotiation messages should no longer
193 * be received and should be ignored if they do occur.)
195 unsigned int have_received_enc_pkt : 1;
198 * Have we sent literally any packet yet? If not, there is no point polling
201 unsigned int have_sent_any_pkt : 1;
204 * Are we currently doing proactive version negotiation?
206 unsigned int doing_proactive_ver_neg : 1;
208 /* We have received transport parameters from the peer. */
209 unsigned int got_remote_transport_params : 1;
212 * This monotonically transitions to 1 once the TLS state machine is
213 * 'complete', meaning that it has both sent a Finished and successfully
214 * verified the peer's Finished (see RFC 9001 s. 4.1.1). Note that it
215 * does not transition to 1 at both peers simultaneously.
217 * Handshake completion is not the same as handshake confirmation (see
220 unsigned int handshake_complete : 1;
223 * This monotonically transitions to 1 once the handshake is confirmed.
224 * This happens on the client when we receive a HANDSHAKE_DONE frame.
225 * At our option, we may also take acknowledgement of any 1-RTT packet
226 * we sent as a handshake confirmation.
228 unsigned int handshake_confirmed : 1;
231 * We are sending Initial packets based on a Retry. This means we definitely
232 * should not receive another Retry, and if we do it is an error.
234 unsigned int doing_retry : 1;
237 * We don't store the current EL here; the TXP asks the QTX which ELs
238 * are provisioned to determine which ELs to use.
241 /* Have statm, qsm been initialised? Used to track cleanup. */
242 unsigned int have_statm : 1;
243 unsigned int have_qsm : 1;
246 * Preferred ELs for transmission and reception. This is not strictly needed
247 * as it can be inferred from what keys we have provisioned, but makes
248 * determining the current EL simpler and faster. A separate EL for
249 * transmission and reception is not strictly necessary but makes things
250 * easier for interoperation with the handshake layer, which likes to invoke
251 * the yield secret callback at different times for TX and RX.
253 unsigned int tx_enc_level : 3;
254 unsigned int rx_enc_level : 3;
256 /* If bit n is set, EL n has been discarded. */
257 unsigned int el_discarded : 4;
260 * While in TERMINATING - CLOSING, set when we should generate a connection
263 unsigned int conn_close_queued : 1;
265 /* Are we in server mode? Never changes after instantiation. */
266 unsigned int is_server : 1;
269 * Set temporarily when the handshake layer has given us a new RX secret.
270 * Used to determine if we need to check our RX queues again.
272 unsigned int have_new_rx_secret : 1;
275 * Have we sent an ack-eliciting packet since the last successful packet
276 * reception? Used to determine when to bump idle timer (see RFC 9000 s.
279 unsigned int have_sent_ack_eliciting_since_rx : 1;