xref: /openssl/ssl/quic/quic_channel_local.h (revision 827475fc)
1 #ifndef OSSL_QUIC_CHANNEL_LOCAL_H
2 # define OSSL_QUIC_CHANNEL_LOCAL_H
3 
4 # include "internal/quic_channel.h"
5 
6 # ifndef OPENSSL_NO_QUIC
7 
8 #  include <openssl/lhash.h>
9 #  include "internal/list.h"
10 #  include "internal/quic_predef.h"
11 #  include "internal/quic_fc.h"
12 #  include "internal/quic_stream_map.h"
13 
14 /*
15  * QUIC Channel Structure
16  * ======================
17  *
18  * QUIC channel internals. It is intended that only the QUIC_CHANNEL
19  * implementation and the RX depacketiser be allowed to access this structure
20  * directly. As the RX depacketiser has no state of its own and computes over a
21  * QUIC_CHANNEL structure, it can be viewed as an extension of the QUIC_CHANNEL
22  * implementation. While the RX depacketiser could be provided with adequate
23  * accessors to do what it needs, this would weaken the abstraction provided by
24  * the QUIC_CHANNEL to other components; moreover the coupling of the RX
25  * depacketiser to QUIC_CHANNEL internals is too deep and bespoke to make this
26  * desirable.
27  *
28  * Other components should not include this header.
29  */
30 struct quic_channel_st {
31     QUIC_PORT                       *port;
32 
33     /*
34      * QUIC_PORT keeps the channels which belong to it on a list for bookkeeping
35      * purposes.
36      */
37     OSSL_LIST_MEMBER(ch, struct quic_channel_st);
38 
39     /*
40      * The associated TLS 1.3 connection data. Used to provide the handshake
41      * layer; its 'network' side is plugged into the crypto stream for each EL
42      * (other than the 0-RTT EL).
43      */
44     QUIC_TLS                        *qtls;
45     SSL                             *tls;
46 
47     /* Port LCIDM we use to register LCIDs. */
48     QUIC_LCIDM                      *lcidm;
49     /* SRTM we register SRTs with. */
50     QUIC_SRTM                       *srtm;
51 
52     /* Optional QLOG instance (or NULL). */
53     QLOG                            *qlog;
54 
55     /*
56      * The transport parameter block we will send or have sent.
57      * Freed after sending or when connection is freed.
58      */
59     unsigned char                   *local_transport_params;
60 
61     /* Our current L4 peer address, if any. */
62     BIO_ADDR                        cur_peer_addr;
63 
64     /*
65      * Subcomponents of the connection. All of these components are instantiated
66      * and owned by us.
67      */
68     OSSL_QUIC_TX_PACKETISER         *txp;
69     QUIC_TXPIM                      *txpim;
70     QUIC_CFQ                        *cfq;
71     /*
72      * Connection level FC. The stream_count RXFCs is used to manage
73      * MAX_STREAMS signalling.
74      */
75     QUIC_TXFC                       conn_txfc;
76     QUIC_RXFC                       conn_rxfc, crypto_rxfc[QUIC_PN_SPACE_NUM];
77     QUIC_RXFC                       max_streams_bidi_rxfc, max_streams_uni_rxfc;
78     QUIC_STREAM_MAP                 qsm;
79     OSSL_STATM                      statm;
80     OSSL_CC_DATA                    *cc_data;
81     const OSSL_CC_METHOD            *cc_method;
82     OSSL_ACKM                       *ackm;
83 
84     /* Record layers in the TX and RX directions. */
85     OSSL_QTX                        *qtx;
86     OSSL_QRX                        *qrx;
87 
88     /* Message callback related arguments */
89     ossl_msg_cb                     msg_callback;
90     void                            *msg_callback_arg;
91     SSL                             *msg_callback_ssl;
92 
93     /*
94      * Send and receive parts of the crypto streams.
95      * crypto_send[QUIC_PN_SPACE_APP] is the 1-RTT crypto stream. There is no
96      * 0-RTT crypto stream.
97      */
98     QUIC_SSTREAM                    *crypto_send[QUIC_PN_SPACE_NUM];
99     QUIC_RSTREAM                    *crypto_recv[QUIC_PN_SPACE_NUM];
100 
101     /* Internal state. */
102     /*
103      * Client: The DCID used in the first Initial packet we transmit as a client.
104      * Server: The DCID used in the first Initial packet the client transmitted.
105      * Randomly generated and required by RFC to be at least 8 bytes.
106      */
107     QUIC_CONN_ID                    init_dcid;
108 
109     /*
110      * Client: The SCID found in the first Initial packet from the server.
111      * Not valid for servers.
112      * Valid if have_received_enc_pkt is set.
113      */
114     QUIC_CONN_ID                    init_scid;
115 
116     /*
117      * Client only: The SCID found in an incoming Retry packet we handled.
118      * Not valid for servers.
119      */
120     QUIC_CONN_ID                    retry_scid;
121 
122     /* Server only: The DCID we currently expect the peer to use to talk to us. */
123     QUIC_CONN_ID                    cur_local_cid;
124 
125     /*
126      * The DCID we currently use to talk to the peer and its sequence num.
127      */
128     QUIC_CONN_ID                    cur_remote_dcid;
129     uint64_t                        cur_remote_seq_num;
130     uint64_t                        cur_retire_prior_to;
131 
132     /* Transport parameter values we send to our peer. */
133     uint64_t                        tx_init_max_stream_data_bidi_local;
134     uint64_t                        tx_init_max_stream_data_bidi_remote;
135     uint64_t                        tx_init_max_stream_data_uni;
136     uint64_t                        tx_max_ack_delay; /* ms */
137 
138     /* Transport parameter values received from server. */
139     uint64_t                        rx_init_max_stream_data_bidi_local;
140     uint64_t                        rx_init_max_stream_data_bidi_remote;
141     uint64_t                        rx_init_max_stream_data_uni;
142     uint64_t                        rx_max_ack_delay; /* ms */
143     unsigned char                   rx_ack_delay_exp;
144 
145     /* Diagnostic counters for testing purposes only. May roll over. */
146     uint16_t                        diag_num_rx_ack; /* Number of ACK frames received */
147 
148     /*
149      * Temporary staging area to store information about the incoming packet we
150      * are currently processing.
151      */
152     OSSL_QRX_PKT                    *qrx_pkt;
153 
154     /*
155      * Current limit on number of streams we may create. Set by transport
156      * parameters initially and then by MAX_STREAMS frames.
157      */
158     uint64_t                        max_local_streams_bidi;
159     uint64_t                        max_local_streams_uni;
160 
161     /* The idle timeout values we and our peer requested. */
162     uint64_t                        max_idle_timeout_local_req;
163     uint64_t                        max_idle_timeout_remote_req;
164 
165     /* The negotiated maximum idle timeout in milliseconds. */
166     uint64_t                        max_idle_timeout;
167 
168     /*
169      * Maximum payload size in bytes for datagrams sent to our peer, as
170      * negotiated by transport parameters.
171      */
172     uint64_t                        rx_max_udp_payload_size;
173     /* Maximum active CID limit, as negotiated by transport parameters. */
174     uint64_t                        rx_active_conn_id_limit;
175 
176     /*
177      * Used to allocate stream IDs. This is a stream ordinal, i.e., a stream ID
178      * without the low two bits designating type and initiator. Shift and or in
179      * the type bits to convert to a stream ID.
180      */
181     uint64_t                        next_local_stream_ordinal_bidi;
182     uint64_t                        next_local_stream_ordinal_uni;
183 
184     /*
185      * Used to track which stream ordinals within a given stream type have been
186      * used by the remote peer. This is an optimisation used to determine
187      * which streams should be implicitly created due to usage of a higher
188      * stream ordinal.
189      */
190     uint64_t                        next_remote_stream_ordinal_bidi;
191     uint64_t                        next_remote_stream_ordinal_uni;
192 
193     /*
194      * Application error code to be used for STOP_SENDING/RESET_STREAM frames
195      * used to autoreject incoming streams.
196      */
197     uint64_t                        incoming_stream_auto_reject_aec;
198 
199     /*
200      * Override packet count threshold at which we do a spontaneous TXKU.
201      * Usually UINT64_MAX in which case a suitable value is chosen based on AEAD
202      * limit advice from the QRL utility functions. This is intended for testing
203      * use only. Usually set to UINT64_MAX.
204      */
205     uint64_t                        txku_threshold_override;
206 
207     /* Valid if we are in the TERMINATING or TERMINATED states. */
208     QUIC_TERMINATE_CAUSE            terminate_cause;
209 
210     /*
211      * Deadline at which we move to TERMINATING state. Valid if in the
212      * TERMINATING state.
213      */
214     OSSL_TIME                       terminate_deadline;
215 
216     /*
217      * Deadline at which connection dies due to idle timeout if no further
218      * events occur.
219      */
220     OSSL_TIME                       idle_deadline;
221 
222     /*
223      * Deadline at which we should send an ACK-eliciting packet to ensure
224      * idle timeout does not occur.
225      */
226     OSSL_TIME                       ping_deadline;
227 
228     /*
229      * The deadline at which the period in which it is RECOMMENDED that we not
230      * initiate any spontaneous TXKU ends. This is zero if no such deadline
231      * applies.
232      */
233     OSSL_TIME                       txku_cooldown_deadline;
234 
235     /*
236      * The deadline at which we take the QRX out of UPDATING and back to NORMAL.
237      * Valid if rxku_in_progress in 1.
238      */
239     OSSL_TIME                       rxku_update_end_deadline;
240 
241     /*
242      * The first (application space) PN sent with a new key phase. Valid if the
243      * QTX key epoch is greater than 0. Once a packet we sent with a PN p (p >=
244      * txku_pn) is ACKed, the TXKU is considered completed and txku_in_progress
245      * becomes 0. For sanity's sake, such a PN p should also be <= the highest
246      * PN we have ever sent, of course.
247      */
248     QUIC_PN                         txku_pn;
249 
250     /*
251      * The (application space) PN which triggered RXKU detection. Valid if
252      * rxku_pending_confirm.
253      */
254     QUIC_PN                         rxku_trigger_pn;
255 
256     /*
257      * State tracking. QUIC connection-level state is best represented based on
258      * whether various things have happened yet or not, rather than as an
259      * explicit FSM. We do have a coarse state variable which tracks the basic
260      * state of the connection's lifecycle, but more fine-grained conditions of
261      * the Active state are tracked via flags below. For more details, see
262      * doc/designs/quic-design/connection-state-machine.md. We are in the Open
263      * state if the state is QUIC_CHANNEL_STATE_ACTIVE and handshake_confirmed is
264      * set.
265      */
266     unsigned int                    state                   : 3;
267 
268     /*
269      * Have we received at least one encrypted packet from the peer?
270      * (If so, Retry and Version Negotiation messages should no longer
271      *  be received and should be ignored if they do occur.)
272      */
273     unsigned int                    have_received_enc_pkt   : 1;
274 
275     /*
276      * Have we successfully processed any packet, including a Version
277      * Negotiation packet? If so, further Version Negotiation packets should be
278      * ignored.
279      */
280     unsigned int                    have_processed_any_pkt  : 1;
281 
282     /*
283      * Have we sent literally any packet yet? If not, there is no point polling
284      * RX.
285      */
286     unsigned int                    have_sent_any_pkt       : 1;
287 
288     /*
289      * Are we currently doing proactive version negotiation?
290      */
291     unsigned int                    doing_proactive_ver_neg : 1;
292 
293     /* We have received transport parameters from the peer. */
294     unsigned int                    got_remote_transport_params    : 1;
295     /* We have generated our local transport parameters. */
296     unsigned int                    got_local_transport_params     : 1;
297 
298     /*
299      * This monotonically transitions to 1 once the TLS state machine is
300      * 'complete', meaning that it has both sent a Finished and successfully
301      * verified the peer's Finished (see RFC 9001 s. 4.1.1). Note that it
302      * does not transition to 1 at both peers simultaneously.
303      *
304      * Handshake completion is not the same as handshake confirmation (see
305      * below).
306      */
307     unsigned int                    handshake_complete      : 1;
308 
309     /*
310      * This monotonically transitions to 1 once the handshake is confirmed.
311      * This happens on the client when we receive a HANDSHAKE_DONE frame.
312      * At our option, we may also take acknowledgement of any 1-RTT packet
313      * we sent as a handshake confirmation.
314      */
315     unsigned int                    handshake_confirmed     : 1;
316 
317     /*
318      * We are sending Initial packets based on a Retry. This means we definitely
319      * should not receive another Retry, and if we do it is an error.
320      */
321     unsigned int                    doing_retry             : 1;
322 
323     /*
324      * We don't store the current EL here; the TXP asks the QTX which ELs
325      * are provisioned to determine which ELs to use.
326      */
327 
328     /* Have statm, qsm been initialised? Used to track cleanup. */
329     unsigned int                    have_statm              : 1;
330     unsigned int                    have_qsm                : 1;
331 
332     /*
333      * Preferred ELs for transmission and reception. This is not strictly needed
334      * as it can be inferred from what keys we have provisioned, but makes
335      * determining the current EL simpler and faster. A separate EL for
336      * transmission and reception is not strictly necessary but makes things
337      * easier for interoperation with the handshake layer, which likes to invoke
338      * the yield secret callback at different times for TX and RX.
339      */
340     unsigned int                    tx_enc_level            : 3;
341     unsigned int                    rx_enc_level            : 3;
342 
343     /* If bit n is set, EL n has been discarded. */
344     unsigned int                    el_discarded            : 4;
345 
346     /*
347      * While in TERMINATING - CLOSING, set when we should generate a connection
348      * close frame.
349      */
350     unsigned int                    conn_close_queued       : 1;
351 
352     /* Are we in server mode? Never changes after instantiation. */
353     unsigned int                    is_server               : 1;
354 
355     /*
356      * Set temporarily when the handshake layer has given us a new RX secret.
357      * Used to determine if we need to check our RX queues again.
358      */
359     unsigned int                    have_new_rx_secret      : 1;
360 
361     /* Have we ever called QUIC_TLS yet during RX processing? */
362     unsigned int                    did_tls_tick            : 1;
363     /* Has any CRYPTO frame been processed during this tick? */
364     unsigned int                    did_crypto_frame        : 1;
365 
366     /*
367      * Have we sent an ack-eliciting packet since the last successful packet
368      * reception? Used to determine when to bump idle timer (see RFC 9000 s.
369      * 10.1).
370      */
371     unsigned int                    have_sent_ack_eliciting_since_rx    : 1;
372 
373     /* Should incoming streams automatically be rejected? */
374     unsigned int                    incoming_stream_auto_reject         : 1;
375 
376     /*
377      * 1 if a key update sequence was locally initiated, meaning we sent the
378      * TXKU first and the resultant RXKU shouldn't result in our triggering
379      * another TXKU. 0 if a key update sequence was initiated by the peer,
380      * meaning we detect a RXKU first and have to generate a TXKU in response.
381      */
382     unsigned int                    ku_locally_initiated                : 1;
383 
384     /*
385      * 1 if we have triggered TXKU (whether spontaneous or solicited) but are
386      * waiting for any PN using that new KP to be ACKed. While this is set, we
387      * are not allowed to trigger spontaneous TXKU (but solicited TXKU is
388      * potentially still possible).
389      */
390     unsigned int                    txku_in_progress                    : 1;
391 
392     /*
393      * We have received an RXKU event and currently are going through
394      * UPDATING/COOLDOWN on the QRX. COOLDOWN is currently not used. Since RXKU
395      * cannot be detected in this state, this doesn't cause a protocol error or
396      * anything similar if a peer tries TXKU in this state. That traffic would
397      * simply be dropped. It's only used to track that our UPDATING timer is
398      * active so we know when to take the QRX out of UPDATING and back to
399      * NORMAL.
400      */
401     unsigned int                    rxku_in_progress                    : 1;
402 
403     /*
404      * We have received an RXKU but have yet to send an ACK for it, which means
405      * no further RXKUs are allowed yet. Note that we cannot detect further
406      * RXKUs anyway while the QRX remains in the UPDATING/COOLDOWN states, so
407      * this restriction comes into play if we take more than PTO time to send
408      * an ACK for it (not likely).
409      */
410     unsigned int                    rxku_pending_confirm                : 1;
411 
412     /* Temporary variable indicating rxku_pending_confirm is to become 0. */
413     unsigned int                    rxku_pending_confirm_done           : 1;
414 
415     /*
416      * If set, RXKU is expected (because we initiated a spontaneous TXKU).
417      */
418     unsigned int                    rxku_expected                       : 1;
419 
420     /* Permanent net error encountered */
421     unsigned int                    net_error                           : 1;
422 
423     /*
424      * Protocol error encountered. Note that you should refer to the state field
425      * rather than this. This is only used so we can ignore protocol errors
426      * after the first protocol error, but still record the first protocol error
427      * if it happens during the TERMINATING state.
428      */
429     unsigned int                    protocol_error                      : 1;
430 
431     /* Are we using addressed mode? */
432     unsigned int                    addressed_mode                      : 1;
433 
434     /* Are we on the QUIC_PORT linked list of channels? */
435     unsigned int                    on_port_list                        : 1;
436 
437     /* Has qlog been requested? */
438     unsigned int                    use_qlog                            : 1;
439 
440     /* Saved error stack in case permanent error was encountered */
441     ERR_STATE                       *err_state;
442 
443     /* Scratch area for use by RXDP to store decoded ACK ranges. */
444     OSSL_QUIC_ACK_RANGE             *ack_range_scratch;
445     size_t                          num_ack_range_scratch;
446 
447     /* Title for qlog purposes. We own this copy. */
448     char                            *qlog_title;
449 };
450 
451 # endif
452 
453 #endif
454