include/internal/quic_channel.h

   1 /*
   2  * Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #ifndef OSSL_QUIC_CHANNEL_H
  11 # define OSSL_QUIC_CHANNEL_H
  12
  13 # include <openssl/ssl.h>
  14 # include "internal/quic_types.h"
  15 # include "internal/quic_record_tx.h"
  16 # include "internal/quic_wire.h"
  17 # include "internal/quic_predef.h"
  18 # include "internal/time.h"
  19 # include "internal/thread.h"
  20
  21 # ifndef OPENSSL_NO_QUIC
  22
  23 /*
  24  * QUIC Channel
  25  * ============
  26  *
  27  * A QUIC channel (QUIC_CHANNEL) is an object which binds together all of the
  28  * various pieces of QUIC into a single top-level object, and handles connection
  29  * state which is not specific to the client or server roles. In particular, it
  30  * is strictly separated from the libssl front end I/O API personality layer,
  31  * and is not an SSL object.
  32  *
  33  * The name QUIC_CHANNEL is chosen because QUIC_CONNECTION is already in use,
  34  * but functionally these relate to the same thing (a QUIC connection). The use
  35  * of two separate objects ensures clean separation between the API personality
  36  * layer and common code for handling connections, and between the functionality
  37  * which is specific to clients and which is specific to servers, and the
  38  * functionality which is common to both.
  39  *
  40  * The API personality layer provides SSL objects (e.g. a QUIC_CONNECTION) which
  41  * consume a QUIC channel and implement a specific public API. Things which are
  42  * handled by the API personality layer include emulation of blocking semantics,
  43  * handling of SSL object mode flags like non-partial write mode, etc.
  44  *
  45  * Where the QUIC_CHANNEL is used in a server role, there is one QUIC_CHANNEL
  46  * per connection. In the future a QUIC Channel Manager will probably be defined
  47  * to handle ownership of resources which are shared between connections (e.g.
  48  * demuxers). Since we only use server-side functionality for dummy test servers
  49  * for now, which only need to handle one connection at a time, this is not
  50  * currently modelled.
  51  *
  52  * Synchronisation
  53  * ---------------
  54  *
  55  * To support thread assisted mode, QUIC_CHANNEL can be used by multiple
  56  * threads. **It is the caller's responsibility to ensure that the QUIC_CHANNEL
  57  * is only accessed (whether via its methods or via direct access to its state)
  58  * while the channel mutex is held**, except for methods explicitly marked as
  59  * not requiring prior locking. This is an unchecked precondition.
  60  *
  61  * The instantiator of the channel is responsible for providing a suitable
  62  * mutex which then serves as the channel mutex; see QUIC_CHANNEL_ARGS.
  63  */
  64
  65 /*
  66  * The function does not acquire the channel mutex and assumes it is already
  67  * held by the calling thread.
  68  *
  69  * Any function tagged with this has the following precondition:
  70  *
  71  *   Precondition: must hold channel mutex (unchecked)
  72  */
  73 #  define QUIC_NEEDS_LOCK
  74
  75 /*
  76  * The function acquires the channel mutex and releases it before returning in
  77  * all circumstances.
  78  *
  79  * Any function tagged with this has the following precondition and
  80  * postcondition:
  81  *
  82  *   Precondition: must not hold channel mutex (unchecked)
  83  *   Postcondition: channel mutex is not held (by calling thread)
  84  */
  85 #  define QUIC_TAKES_LOCK
  86
  87 /*
  88  * The function acquires the channel mutex and leaves it acquired
  89  * when returning success.
  90  *
  91  * Any function tagged with this has the following precondition and
  92  * postcondition:
  93  *
  94  *   Precondition: must not hold channel mutex (unchecked)
  95  *   Postcondition: channel mutex is held by calling thread
  96  *      or function returned failure
  97  */
  98 #  define QUIC_ACQUIRES_LOCK
  99
 100 #  define QUIC_TODO_LOCK
 101
 102 #  define QUIC_CHANNEL_STATE_IDLE                        0
 103 #  define QUIC_CHANNEL_STATE_ACTIVE                      1
 104 #  define QUIC_CHANNEL_STATE_TERMINATING_CLOSING         2
 105 #  define QUIC_CHANNEL_STATE_TERMINATING_DRAINING        3
 106 #  define QUIC_CHANNEL_STATE_TERMINATED                  4
 107
 108 typedef struct quic_channel_args_st {
 109     /*
 110      * The QUIC_PORT which the channel is to belong to. The lifetime of the
 111      * QUIC_PORT must exceed that of the created channel.
 112      */
 113     QUIC_PORT       *port;
 114
 115     int             is_server;
 116     SSL             *tls;
 117 } QUIC_CHANNEL_ARGS;
 118
 119 typedef struct quic_channel_st QUIC_CHANNEL;
 120
 121 /* Represents the cause for a connection's termination. */
 122 typedef struct quic_terminate_cause_st {
 123     /*
 124      * If we are in a TERMINATING or TERMINATED state, this is the error code
 125      * associated with the error. This field is valid iff we are in the
 126      * TERMINATING or TERMINATED states.
 127      */
 128     uint64_t                        error_code;
 129
 130     /*
 131      * If terminate_app is set and this is nonzero, this is the frame type which
 132      * caused the connection to be terminated.
 133      */
 134     uint64_t                        frame_type;
 135
 136     /*
 137      * Optional reason string. When calling ossl_quic_channel_local_close, if a
 138      * reason string pointer is passed, it is copied and stored inside
 139      * QUIC_CHANNEL for the remainder of the lifetime of the channel object.
 140      * Thus the string pointed to by this value, if non-NULL, is valid for the
 141      * lifetime of the QUIC_CHANNEL object.
 142      */
 143     const char                      *reason;
 144
 145     /*
 146      * Length of reason in bytes. The reason is supposed to contain a UTF-8
 147      * string but may be arbitrary data if the reason came from the network.
 148      */
 149     size_t                          reason_len;
 150
 151     /* Is this error code in the transport (0) or application (1) space? */
 152     unsigned int                    app : 1;
 153
 154     /*
 155      * If set, the cause of the termination is a received CONNECTION_CLOSE
 156      * frame. Otherwise, we decided to terminate ourselves and sent a
 157      * CONNECTION_CLOSE frame (regardless of whether the peer later also sends
 158      * one).
 159      */
 160     unsigned int                    remote : 1;
 161 } QUIC_TERMINATE_CAUSE;
 162
 163
 164 /*
 165  * Create a new QUIC channel using the given arguments. The argument structure
 166  * does not need to remain allocated. Returns NULL on failure.
 167  *
 168  * Only QUIC_PORT should use this function.
 169  */
 170 QUIC_CHANNEL *ossl_quic_channel_new(const QUIC_CHANNEL_ARGS *args);
 171
 172 /* No-op if ch is NULL. */
 173 void ossl_quic_channel_free(QUIC_CHANNEL *ch);
 174
 175 /* Set mutator callbacks for test framework support */
 176 int ossl_quic_channel_set_mutator(QUIC_CHANNEL *ch,
 177                                   ossl_mutate_packet_cb mutatecb,
 178                                   ossl_finish_mutate_cb finishmutatecb,
 179                                   void *mutatearg);
 180
 181 /*
 182  * Connection Lifecycle Events
 183  * ===========================
 184  *
 185  * Various events that can be raised on the channel by other parts of the QUIC
 186  * implementation. Some of these are suitable for general use by any part of the
 187  * code (e.g. ossl_quic_channel_raise_protocol_error), others are for very
 188  * specific use by particular components only (e.g.
 189  * ossl_quic_channel_on_handshake_confirmed).
 190  */
 191
 192 /*
 193  * To be used by a QUIC connection. Starts the channel. For a client-mode
 194  * channel, this starts sending the first handshake layer message, etc. Can only
 195  * be called in the idle state; successive calls are ignored.
 196  */
 197 int ossl_quic_channel_start(QUIC_CHANNEL *ch);
 198
 199 /* Start a locally initiated connection shutdown. */
 200 void ossl_quic_channel_local_close(QUIC_CHANNEL *ch, uint64_t app_error_code,
 201                                    const char *app_reason);
 202
 203 /*
 204  * Called when the handshake is confirmed.
 205  */
 206 int ossl_quic_channel_on_handshake_confirmed(QUIC_CHANNEL *ch);
 207
 208 /*
 209  * Raises a protocol error. This is intended to be the universal call suitable
 210  * for handling of all peer-triggered protocol violations or errors detected by
 211  * us. We specify a QUIC transport-scope error code and optional frame type
 212  * which was responsible. If a frame type is not applicable, specify zero. The
 213  * reason string is not currently handled, but should be a string of static
 214  * storage duration. If the connection has already terminated due to a previous
 215  * protocol error, this is a no-op; first error wins.
 216  *
 217  * Usually the ossl_quic_channel_raise_protocol_error() function should be used.
 218  * The ossl_quic_channel_raise_protocol_error_loc() function can be used
 219  * directly for passing through existing call site information from an existing
 220  * error.
 221  */
 222 void ossl_quic_channel_raise_protocol_error_loc(QUIC_CHANNEL *ch,
 223                                                 uint64_t error_code,
 224                                                 uint64_t frame_type,
 225                                                 const char *reason,
 226                                                 ERR_STATE *err_state,
 227                                                 const char *src_file,
 228                                                 int src_line,
 229                                                 const char *src_func);
 230
 231 #define ossl_quic_channel_raise_protocol_error(ch, error_code, frame_type, reason) \
 232     ossl_quic_channel_raise_protocol_error_loc((ch), (error_code),  \
 233                                                (frame_type),        \
 234                                                (reason),            \
 235                                                NULL,                \
 236                                                OPENSSL_FILE,        \
 237                                                OPENSSL_LINE,        \
 238                                                OPENSSL_FUNC)
 239
 240 #define ossl_quic_channel_raise_protocol_error_state(ch, error_code, frame_type, reason, state) \
 241     ossl_quic_channel_raise_protocol_error_loc((ch), (error_code),  \
 242                                                (frame_type),        \
 243                                                (reason),            \
 244                                                (state),             \
 245                                                OPENSSL_FILE,        \
 246                                                OPENSSL_LINE,        \
 247                                                OPENSSL_FUNC)
 248
 249
 250 /*
 251  * Returns 1 if permanent net error was detected on the QUIC_CHANNEL,
 252  * 0 otherwise.
 253  */
 254 int ossl_quic_channel_net_error(QUIC_CHANNEL *ch);
 255
 256 /* Restore saved error state (best effort) */
 257 void ossl_quic_channel_restore_err_state(QUIC_CHANNEL *ch);
 258
 259 /* For RXDP use. */
 260 void ossl_quic_channel_on_remote_conn_close(QUIC_CHANNEL *ch,
 261                                             OSSL_QUIC_FRAME_CONN_CLOSE *f);
 262 void ossl_quic_channel_on_new_conn_id(QUIC_CHANNEL *ch,
 263                                       OSSL_QUIC_FRAME_NEW_CONN_ID *f);
 264
 265 /* Temporarily exposed during QUIC_PORT transition. */
 266 int ossl_quic_channel_on_new_conn(QUIC_CHANNEL *ch, const BIO_ADDR *peer,
 267                                   const QUIC_CONN_ID *peer_scid,
 268                                   const QUIC_CONN_ID *peer_dcid);
 269
 270 /* For use by QUIC_PORT. You should not need to call this directly. */
 271 void ossl_quic_channel_subtick(QUIC_CHANNEL *ch, QUIC_TICK_RESULT *r,
 272                                uint32_t flags);
 273
 274 /* For use by QUIC_PORT only. */
 275 void ossl_quic_channel_raise_net_error(QUIC_CHANNEL *ch);
 276
 277 /*
 278  * Queries and Accessors
 279  * =====================
 280  */
 281
 282 /* Gets the reactor which can be used to tick/poll on the channel. */
 283 QUIC_REACTOR *ossl_quic_channel_get_reactor(QUIC_CHANNEL *ch);
 284
 285 /* Gets the QSM used with the channel. */
 286 QUIC_STREAM_MAP *ossl_quic_channel_get_qsm(QUIC_CHANNEL *ch);
 287
 288 /* Gets the statistics manager used with the channel. */
 289 OSSL_STATM *ossl_quic_channel_get_statm(QUIC_CHANNEL *ch);
 290
 291 /*
 292  * Gets/sets the current peer address. Generally this should be used before
 293  * starting a channel in client mode.
 294  */
 295 int ossl_quic_channel_get_peer_addr(QUIC_CHANNEL *ch, BIO_ADDR *peer_addr);
 296 int ossl_quic_channel_set_peer_addr(QUIC_CHANNEL *ch, const BIO_ADDR *peer_addr);
 297
 298 /* Gets/sets the underlying network read and write BIOs. */
 299 BIO *ossl_quic_channel_get_net_rbio(QUIC_CHANNEL *ch);
 300 BIO *ossl_quic_channel_get_net_wbio(QUIC_CHANNEL *ch);
 301 int ossl_quic_channel_set_net_rbio(QUIC_CHANNEL *ch, BIO *net_rbio);
 302 int ossl_quic_channel_set_net_wbio(QUIC_CHANNEL *ch, BIO *net_wbio);
 303
 304 /*
 305  * Returns an existing stream by stream ID. Returns NULL if the stream does not
 306  * exist.
 307  */
 308 QUIC_STREAM *ossl_quic_channel_get_stream_by_id(QUIC_CHANNEL *ch,
 309                                                 uint64_t stream_id);
 310
 311 /* Returns 1 if channel is terminating or terminated. */
 312 int ossl_quic_channel_is_term_any(const QUIC_CHANNEL *ch);
 313 const QUIC_TERMINATE_CAUSE *
 314 ossl_quic_channel_get_terminate_cause(const QUIC_CHANNEL *ch);
 315 int ossl_quic_channel_is_closing(const QUIC_CHANNEL *ch);
 316 int ossl_quic_channel_is_terminated(const QUIC_CHANNEL *ch);
 317 int ossl_quic_channel_is_active(const QUIC_CHANNEL *ch);
 318 int ossl_quic_channel_is_handshake_complete(const QUIC_CHANNEL *ch);
 319 int ossl_quic_channel_is_handshake_confirmed(const QUIC_CHANNEL *ch);
 320
 321 QUIC_PORT *ossl_quic_channel_get0_port(QUIC_CHANNEL *ch);
 322 QUIC_DEMUX *ossl_quic_channel_get0_demux(QUIC_CHANNEL *ch);
 323
 324 SSL *ossl_quic_channel_get0_ssl(QUIC_CHANNEL *ch);
 325
 326 /*
 327  * Retrieves a pointer to the channel mutex which was provided at the time the
 328  * channel was instantiated. In order to allow locks to be acquired and released
 329  * with the correct granularity, it is the caller's responsibility to ensure
 330  * this lock is held for write while calling any QUIC_CHANNEL method, except for
 331  * methods explicitly designed otherwise.
 332  *
 333  * This method is thread safe and does not require prior locking. It can also be
 334  * called while the lock is already held. Note that this is simply a convenience
 335  * function to access the mutex which was passed to the channel at instantiation
 336  * time; it does not belong to the channel but rather is presumed to belong to
 337  * the owner of the channel.
 338  */
 339 CRYPTO_MUTEX *ossl_quic_channel_get_mutex(QUIC_CHANNEL *ch);
 340
 341 /*
 342  * Creates a new locally-initiated stream in the stream mapper, choosing an
 343  * appropriate stream ID. If is_uni is 1, creates a unidirectional stream, else
 344  * creates a bidirectional stream. Returns NULL on failure.
 345  */
 346 QUIC_STREAM *ossl_quic_channel_new_stream_local(QUIC_CHANNEL *ch, int is_uni);
 347
 348 /*
 349  * Creates a new remotely-initiated stream in the stream mapper. The stream ID
 350  * is used to confirm the initiator and determine the stream type. The stream is
 351  * automatically added to the QSM's accept queue. A pointer to the stream is
 352  * also returned. Returns NULL on failure.
 353  */
 354 QUIC_STREAM *ossl_quic_channel_new_stream_remote(QUIC_CHANNEL *ch,
 355                                                  uint64_t stream_id);
 356
 357 /*
 358  * Configures incoming stream auto-reject. If enabled, incoming streams have
 359  * both their sending and receiving parts automatically rejected using
 360  * STOP_SENDING and STREAM_RESET frames. aec is the application error
 361  * code to be used for those frames.
 362  */
 363 void ossl_quic_channel_set_incoming_stream_auto_reject(QUIC_CHANNEL *ch,
 364                                                        int enable,
 365                                                        uint64_t aec);
 366
 367 /*
 368  * Causes the channel to reject the sending and receiving parts of a stream,
 369  * as though autorejected. Can be used if a stream has already been
 370  * accepted.
 371  */
 372 void ossl_quic_channel_reject_stream(QUIC_CHANNEL *ch, QUIC_STREAM *qs);
 373
 374 /* Replace local connection ID in TXP and DEMUX for testing purposes. */
 375 int ossl_quic_channel_replace_local_cid(QUIC_CHANNEL *ch,
 376                                         const QUIC_CONN_ID *conn_id);
 377
 378 /* Setters for the msg_callback and msg_callback_arg */
 379 void ossl_quic_channel_set_msg_callback(QUIC_CHANNEL *ch,
 380                                         ossl_msg_cb msg_callback,
 381                                         SSL *msg_callback_ssl);
 382 void ossl_quic_channel_set_msg_callback_arg(QUIC_CHANNEL *ch,
 383                                             void *msg_callback_arg);
 384
 385 /* Testing use only - sets a TXKU threshold packet count override value. */
 386 void ossl_quic_channel_set_txku_threshold_override(QUIC_CHANNEL *ch,
 387                                                    uint64_t tx_pkt_threshold);
 388
 389 /* Testing use only - gets current 1-RTT key epochs for QTX and QRX. */
 390 uint64_t ossl_quic_channel_get_tx_key_epoch(QUIC_CHANNEL *ch);
 391 uint64_t ossl_quic_channel_get_rx_key_epoch(QUIC_CHANNEL *ch);
 392
 393 /* Artificially trigger a spontaneous TXKU if possible. */
 394 int ossl_quic_channel_trigger_txku(QUIC_CHANNEL *ch);
 395 int ossl_quic_channel_has_pending(const QUIC_CHANNEL *ch);
 396
 397 /* Force transmission of an ACK-eliciting packet. */
 398 int ossl_quic_channel_ping(QUIC_CHANNEL *ch);
 399
 400 /*
 401  * These queries exist for diagnostic purposes only. They may roll over.
 402  * Do not rely on them for non-testing purposes.
 403  */
 404 uint16_t ossl_quic_channel_get_diag_num_rx_ack(QUIC_CHANNEL *ch);
 405
 406 /*
 407  * Diagnostic use only. Gets the current local CID.
 408  */
 409 void ossl_quic_channel_get_diag_local_cid(QUIC_CHANNEL *ch, QUIC_CONN_ID *cid);
 410
 411 /*
 412  * Returns 1 if stream count flow control allows us to create a new
 413  * locally-initiated stream.
 414  */
 415 int ossl_quic_channel_is_new_local_stream_admissible(QUIC_CHANNEL *ch, int is_uni);
 416
 417 # endif
 418
 419 #endif