include/internal/quic_channel.h

   1 /*
   2  * Copyright 2022 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_stream_map.h"
  16 # include "internal/quic_reactor.h"
  17 # include "internal/quic_statm.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     OSSL_LIB_CTX    *libctx;
 110     const char      *propq;
 111     int             is_server;
 112     SSL             *tls;
 113
 114     /*
 115      * This must be a mutex the lifetime of which will exceed that of the
 116      * channel. The instantiator of the channel is responsible for providing a
 117      * mutex as this makes it easier to handle instantiation and teardown of
 118      * channels in situations potentially requiring locking.
 119      *
 120      * Note that this is a MUTEX not a RWLOCK as it needs to be an OS mutex for
 121      * compatibility with an OS's condition variable wait API, whereas RWLOCK
 122      * may, depending on the build configuration, be implemented using an OS's
 123      * mutex primitive or using its RW mutex primitive.
 124      */
 125     CRYPTO_MUTEX    *mutex;
 126
 127     /*
 128      * Optional function pointer to use to retrieve the current time. If NULL,
 129      * ossl_time_now() is used.
 130      */
 131     OSSL_TIME       (*now_cb)(void *arg);
 132     void            *now_cb_arg;
 133 } QUIC_CHANNEL_ARGS;
 134
 135 typedef struct quic_channel_st QUIC_CHANNEL;
 136
 137 /* Represents the cause for a connection's termination. */
 138 typedef struct quic_terminate_cause_st {
 139     /*
 140      * If we are in a TERMINATING or TERMINATED state, this is the error code
 141      * associated with the error. This field is valid iff we are in the
 142      * TERMINATING or TERMINATED states.
 143      */
 144     uint64_t                        error_code;
 145
 146     /*
 147      * If terminate_app is set and this is nonzero, this is the frame type which
 148      * caused the connection to be terminated.
 149      */
 150     uint64_t                        frame_type;
 151
 152     /* Is this error code in the transport (0) or application (1) space? */
 153     unsigned int                    app : 1;
 154
 155     /*
 156      * If set, the cause of the termination is a received CONNECTION_CLOSE
 157      * frame. Otherwise, we decided to terminate ourselves and sent a
 158      * CONNECTION_CLOSE frame (regardless of whether the peer later also sends
 159      * one).
 160      */
 161     unsigned int                    remote : 1;
 162 } QUIC_TERMINATE_CAUSE;
 163
 164
 165 /*
 166  * Create a new QUIC channel using the given arguments. The argument structure
 167  * does not need to remain allocated. Returns NULL on failure.
 168  */
 169 QUIC_CHANNEL *ossl_quic_channel_new(const QUIC_CHANNEL_ARGS *args);
 170
 171 /* No-op if ch is NULL. */
 172 void ossl_quic_channel_free(QUIC_CHANNEL *ch);
 173
 174 /* Set mutator callbacks for test framework support */
 175 int ossl_quic_channel_set_mutator(QUIC_CHANNEL *ch,
 176                                   ossl_mutate_packet_cb mutatecb,
 177                                   ossl_finish_mutate_cb finishmutatecb,
 178                                   void *mutatearg);
 179
 180 /*
 181  * Connection Lifecycle Events
 182  * ===========================
 183  *
 184  * Various events that can be raised on the channel by other parts of the QUIC
 185  * implementation. Some of these are suitable for general use by any part of the
 186  * code (e.g. ossl_quic_channel_raise_protocol_error), others are for very
 187  * specific use by particular components only (e.g.
 188  * ossl_quic_channel_on_handshake_confirmed).
 189  */
 190
 191 /*
 192  * To be used by a QUIC connection. Starts the channel. For a client-mode
 193  * channel, this starts sending the first handshake layer message, etc. Can only
 194  * be called in the idle state; successive calls are ignored.
 195  */
 196 int ossl_quic_channel_start(QUIC_CHANNEL *ch);
 197
 198 /* Start a locally initiated connection shutdown. */
 199 void ossl_quic_channel_local_close(QUIC_CHANNEL *ch, uint64_t app_error_code);
 200
 201 /*
 202  * Called when the handshake is confirmed.
 203  */
 204 int ossl_quic_channel_on_handshake_confirmed(QUIC_CHANNEL *ch);
 205
 206 /*
 207  * Raises a protocol error. This is intended to be the universal call suitable
 208  * for handling of all peer-triggered protocol violations or errors detected by
 209  * us. We specify a QUIC transport-scope error code and optional frame type
 210  * which was responsible. If a frame type is not applicable, specify zero. The
 211  * reason string is not currently handled, but should be a string of static
 212  * storage duration. If the connection has already terminated due to a previous
 213  * protocol error, this is a no-op; first error wins.
 214  */
 215 void ossl_quic_channel_raise_protocol_error(QUIC_CHANNEL *ch,
 216                                             uint64_t error_code,
 217                                             uint64_t frame_type,
 218                                             const char *reason);
 219 /*
 220  * Returns 1 if permanent net error was detected on the QUIC_CHANNEL,
 221  * 0 otherwise.
 222  */
 223 int ossl_quic_channel_net_error(QUIC_CHANNEL *ch);
 224
 225 /* Restore saved error state (best effort) */
 226 void ossl_quic_channel_restore_err_state(QUIC_CHANNEL *ch);
 227
 228 /* For RXDP use. */
 229 void ossl_quic_channel_on_remote_conn_close(QUIC_CHANNEL *ch,
 230                                             OSSL_QUIC_FRAME_CONN_CLOSE *f);
 231 void ossl_quic_channel_on_new_conn_id(QUIC_CHANNEL *ch,
 232                                       OSSL_QUIC_FRAME_NEW_CONN_ID *f);
 233
 234 /*
 235  * Queries and Accessors
 236  * =====================
 237  */
 238
 239 /* Gets the reactor which can be used to tick/poll on the channel. */
 240 QUIC_REACTOR *ossl_quic_channel_get_reactor(QUIC_CHANNEL *ch);
 241
 242 /* Gets the QSM used with the channel. */
 243 QUIC_STREAM_MAP *ossl_quic_channel_get_qsm(QUIC_CHANNEL *ch);
 244
 245 /* Gets the statistics manager used with the channel. */
 246 OSSL_STATM *ossl_quic_channel_get_statm(QUIC_CHANNEL *ch);
 247
 248 /*
 249  * Gets/sets the current peer address. Generally this should be used before
 250  * starting a channel in client mode.
 251  */
 252 int ossl_quic_channel_get_peer_addr(QUIC_CHANNEL *ch, BIO_ADDR *peer_addr);
 253 int ossl_quic_channel_set_peer_addr(QUIC_CHANNEL *ch, const BIO_ADDR *peer_addr);
 254
 255 /* Gets/sets the underlying network read and write BIOs. */
 256 BIO *ossl_quic_channel_get_net_rbio(QUIC_CHANNEL *ch);
 257 BIO *ossl_quic_channel_get_net_wbio(QUIC_CHANNEL *ch);
 258 int ossl_quic_channel_set_net_rbio(QUIC_CHANNEL *ch, BIO *net_rbio);
 259 int ossl_quic_channel_set_net_wbio(QUIC_CHANNEL *ch, BIO *net_wbio);
 260
 261 /*
 262  * Returns an existing stream by stream ID. Returns NULL if the stream does not
 263  * exist.
 264  */
 265 QUIC_STREAM *ossl_quic_channel_get_stream_by_id(QUIC_CHANNEL *ch,
 266                                                 uint64_t stream_id);
 267
 268 /* Returns 1 if channel is terminating or terminated. */
 269 int ossl_quic_channel_is_term_any(const QUIC_CHANNEL *ch);
 270 const QUIC_TERMINATE_CAUSE *
 271 ossl_quic_channel_get_terminate_cause(const QUIC_CHANNEL *ch);
 272 int ossl_quic_channel_is_terminating(const QUIC_CHANNEL *ch);
 273 int ossl_quic_channel_is_terminated(const QUIC_CHANNEL *ch);
 274 int ossl_quic_channel_is_active(const QUIC_CHANNEL *ch);
 275 int ossl_quic_channel_is_handshake_complete(const QUIC_CHANNEL *ch);
 276 int ossl_quic_channel_is_handshake_confirmed(const QUIC_CHANNEL *ch);
 277
 278 QUIC_DEMUX *ossl_quic_channel_get0_demux(QUIC_CHANNEL *ch);
 279
 280 SSL *ossl_quic_channel_get0_ssl(QUIC_CHANNEL *ch);
 281
 282 /*
 283  * Retrieves a pointer to the channel mutex which was provided at the time the
 284  * channel was instantiated. In order to allow locks to be acquired and released
 285  * with the correct granularity, it is the caller's responsibility to ensure
 286  * this lock is held for write while calling any QUIC_CHANNEL method, except for
 287  * methods explicitly designed otherwise.
 288  *
 289  * This method is thread safe and does not require prior locking. It can also be
 290  * called while the lock is already held. Note that this is simply a convenience
 291  * function to access the mutex which was passed to the channel at instantiation
 292  * time; it does not belong to the channel but rather is presumed to belong to
 293  * the owner of the channel.
 294  */
 295 CRYPTO_MUTEX *ossl_quic_channel_get_mutex(QUIC_CHANNEL *ch);
 296
 297 /*
 298  * Creates a new locally-initiated stream in the stream mapper, choosing an
 299  * appropriate stream ID. If is_uni is 1, creates a unidirectional stream, else
 300  * creates a bidirectional stream. Returns NULL on failure.
 301  */
 302 QUIC_STREAM *ossl_quic_channel_new_stream_local(QUIC_CHANNEL *ch, int is_uni);
 303
 304 /*
 305  * Creates a new remotely-initiated stream in the stream mapper. The stream ID
 306  * is used to confirm the initiator and determine the stream type. The stream is
 307  * automatically added to the QSM's accept queue. A pointer to the stream is
 308  * also returned. Returns NULL on failure.
 309  */
 310 QUIC_STREAM *ossl_quic_channel_new_stream_remote(QUIC_CHANNEL *ch,
 311                                                  uint64_t stream_id);
 312
 313 /*
 314  * Configures incoming stream auto-reject. If enabled, incoming streams have
 315  * both their sending and receiving parts automatically rejected using
 316  * STOP_SENDING and STREAM_RESET frames. aec is the application error
 317  * code to be used for those frames.
 318  */
 319 void ossl_quic_channel_set_incoming_stream_auto_reject(QUIC_CHANNEL *ch,
 320                                                        int enable,
 321                                                        uint64_t aec);
 322
 323 /*
 324  * Causes the channel to reject the sending and receiving parts of a stream,
 325  * as though autorejected. Can be used if a stream has already been
 326  * accepted.
 327  */
 328 void ossl_quic_channel_reject_stream(QUIC_CHANNEL *ch, QUIC_STREAM *qs);
 329
 330 /* Replace local connection ID in TXP and DEMUX for testing purposes. */
 331 int ossl_quic_channel_replace_local_cid(QUIC_CHANNEL *ch,
 332                                         const QUIC_CONN_ID *conn_id);
 333
 334 /* Setters for the msg_callback and msg_callback_arg */
 335 void ossl_quic_channel_set_msg_callback(QUIC_CHANNEL *ch,
 336                                         ossl_msg_cb msg_callback,
 337                                         SSL *msg_callback_ssl);
 338 void ossl_quic_channel_set_msg_callback_arg(QUIC_CHANNEL *ch,
 339                                             void *msg_callback_arg);
 340
 341 /* Testing use only - sets a TXKU threshold packet count override value. */
 342 void ossl_quic_channel_set_txku_threshold_override(QUIC_CHANNEL *ch,
 343                                                    uint64_t tx_pkt_threshold);
 344
 345 /* Testing use only - gets current 1-RTT key epochs for QTX and QRX. */
 346 uint64_t ossl_quic_channel_get_tx_key_epoch(QUIC_CHANNEL *ch);
 347 uint64_t ossl_quic_channel_get_rx_key_epoch(QUIC_CHANNEL *ch);
 348
 349 /* Artificially trigger a spontaneous TXKU if possible. */
 350 int ossl_quic_channel_trigger_txku(QUIC_CHANNEL *ch);
 351 int ossl_quic_channel_has_pending(const QUIC_CHANNEL *ch);
 352
 353 # endif
 354
 355 #endif