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 #  define QUIC_TODO_LOCK
  88
  89 #  define QUIC_CHANNEL_STATE_IDLE                        0
  90 #  define QUIC_CHANNEL_STATE_ACTIVE                      1
  91 #  define QUIC_CHANNEL_STATE_TERMINATING_CLOSING         2
  92 #  define QUIC_CHANNEL_STATE_TERMINATING_DRAINING        3
  93 #  define QUIC_CHANNEL_STATE_TERMINATED                  4
  94
  95 typedef struct quic_channel_args_st {
  96     OSSL_LIB_CTX    *libctx;
  97     const char      *propq;
  98     int             is_server;
  99     SSL             *tls;
 100
 101     /*
 102      * This must be a mutex the lifetime of which will exceed that of the
 103      * channel. The instantiator of the channel is responsible for providing a
 104      * mutex as this makes it easier to handle instantiation and teardown of
 105      * channels in situations potentially requiring locking.
 106      *
 107      * Note that this is a MUTEX not a RWLOCK as it needs to be an OS mutex for
 108      * compatibility with an OS's condition variable wait API, whereas RWLOCK
 109      * may, depending on the build configuration, be implemented using an OS's
 110      * mutex primitive or using its RW mutex primitive.
 111      */
 112     CRYPTO_MUTEX    *mutex;
 113
 114     /*
 115      * Optional function pointer to use to retrieve the current time. If NULL,
 116      * ossl_time_now() is used.
 117      */
 118     OSSL_TIME       (*now_cb)(void *arg);
 119     void            *now_cb_arg;
 120 } QUIC_CHANNEL_ARGS;
 121
 122 typedef struct quic_channel_st QUIC_CHANNEL;
 123
 124 /* Represents the cause for a connection's termination. */
 125 typedef struct quic_terminate_cause_st {
 126     /*
 127      * If we are in a TERMINATING or TERMINATED state, this is the error code
 128      * associated with the error. This field is valid iff we are in the
 129      * TERMINATING or TERMINATED states.
 130      */
 131     uint64_t                        error_code;
 132
 133     /*
 134      * If terminate_app is set and this is nonzero, this is the frame type which
 135      * caused the connection to be terminated.
 136      */
 137     uint64_t                        frame_type;
 138
 139     /* Is this error code in the transport (0) or application (1) space? */
 140     unsigned int                    app : 1;
 141
 142     /*
 143      * If set, the cause of the termination is a received CONNECTION_CLOSE
 144      * frame. Otherwise, we decided to terminate ourselves and sent a
 145      * CONNECTION_CLOSE frame (regardless of whether the peer later also sends
 146      * one).
 147      */
 148     unsigned int                    remote : 1;
 149 } QUIC_TERMINATE_CAUSE;
 150
 151
 152 /*
 153  * Create a new QUIC channel using the given arguments. The argument structure
 154  * does not need to remain allocated. Returns NULL on failure.
 155  */
 156 QUIC_CHANNEL *ossl_quic_channel_new(const QUIC_CHANNEL_ARGS *args);
 157
 158 /* No-op if ch is NULL. */
 159 void ossl_quic_channel_free(QUIC_CHANNEL *ch);
 160
 161 /* Set mutator callbacks for test framework support */
 162 int ossl_quic_channel_set_mutator(QUIC_CHANNEL *ch,
 163                                   ossl_mutate_packet_cb mutatecb,
 164                                   ossl_finish_mutate_cb finishmutatecb,
 165                                   void *mutatearg);
 166
 167 /*
 168  * Connection Lifecycle Events
 169  * ===========================
 170  *
 171  * Various events that can be raised on the channel by other parts of the QUIC
 172  * implementation. Some of these are suitable for general use by any part of the
 173  * code (e.g. ossl_quic_channel_raise_protocol_error), others are for very
 174  * specific use by particular components only (e.g.
 175  * ossl_quic_channel_on_handshake_confirmed).
 176  */
 177
 178 /*
 179  * To be used by a QUIC connection. Starts the channel. For a client-mode
 180  * channel, this starts sending the first handshake layer message, etc. Can only
 181  * be called in the idle state; successive calls are ignored.
 182  */
 183 int ossl_quic_channel_start(QUIC_CHANNEL *ch);
 184
 185 /* Start a locally initiated connection shutdown. */
 186 void ossl_quic_channel_local_close(QUIC_CHANNEL *ch, uint64_t app_error_code);
 187
 188 /*
 189  * Called when the handshake is confirmed.
 190  */
 191 int ossl_quic_channel_on_handshake_confirmed(QUIC_CHANNEL *ch);
 192
 193 /*
 194  * Raises a protocol error. This is intended to be the universal call suitable
 195  * for handling of all peer-triggered protocol violations or errors detected by
 196  * us. We specify a QUIC transport-scope error code and optional frame type
 197  * which was responsible. If a frame type is not applicable, specify zero. The
 198  * reason string is not currently handled, but should be a string of static
 199  * storage duration. If the connection has already terminated due to a previous
 200  * protocol error, this is a no-op; first error wins.
 201  */
 202 void ossl_quic_channel_raise_protocol_error(QUIC_CHANNEL *ch,
 203                                             uint64_t error_code,
 204                                             uint64_t frame_type,
 205                                             const char *reason);
 206
 207 /* For RXDP use. */
 208 void ossl_quic_channel_on_remote_conn_close(QUIC_CHANNEL *ch,
 209                                             OSSL_QUIC_FRAME_CONN_CLOSE *f);
 210
 211 /*
 212  * Queries and Accessors
 213  * =====================
 214  */
 215
 216 /* Gets the reactor which can be used to tick/poll on the channel. */
 217 QUIC_REACTOR *ossl_quic_channel_get_reactor(QUIC_CHANNEL *ch);
 218
 219 /* Gets the QSM used with the channel. */
 220 QUIC_STREAM_MAP *ossl_quic_channel_get_qsm(QUIC_CHANNEL *ch);
 221
 222 /* Gets the statistics manager used with the channel. */
 223 OSSL_STATM *ossl_quic_channel_get_statm(QUIC_CHANNEL *ch);
 224
 225 /*
 226  * Gets/sets the current peer address. Generally this should be used before
 227  * starting a channel in client mode.
 228  */
 229 int ossl_quic_channel_get_peer_addr(QUIC_CHANNEL *ch, BIO_ADDR *peer_addr);
 230 int ossl_quic_channel_set_peer_addr(QUIC_CHANNEL *ch, const BIO_ADDR *peer_addr);
 231
 232 /* Gets/sets the underlying network read and write BIOs. */
 233 BIO *ossl_quic_channel_get_net_rbio(QUIC_CHANNEL *ch);
 234 BIO *ossl_quic_channel_get_net_wbio(QUIC_CHANNEL *ch);
 235 int ossl_quic_channel_set_net_rbio(QUIC_CHANNEL *ch, BIO *net_rbio);
 236 int ossl_quic_channel_set_net_wbio(QUIC_CHANNEL *ch, BIO *net_wbio);
 237
 238 /*
 239  * Returns an existing stream by stream ID. Returns NULL if the stream does not
 240  * exist.
 241  */
 242 QUIC_STREAM *ossl_quic_channel_get_stream_by_id(QUIC_CHANNEL *ch,
 243                                                 uint64_t stream_id);
 244
 245 /* Returns 1 if channel is terminating or terminated. */
 246 int ossl_quic_channel_is_term_any(const QUIC_CHANNEL *ch);
 247 QUIC_TERMINATE_CAUSE ossl_quic_channel_get_terminate_cause(const QUIC_CHANNEL *ch);
 248 int ossl_quic_channel_is_terminating(const QUIC_CHANNEL *ch);
 249 int ossl_quic_channel_is_terminated(const QUIC_CHANNEL *ch);
 250 int ossl_quic_channel_is_active(const QUIC_CHANNEL *ch);
 251 int ossl_quic_channel_is_handshake_complete(const QUIC_CHANNEL *ch);
 252 int ossl_quic_channel_is_handshake_confirmed(const QUIC_CHANNEL *ch);
 253
 254 QUIC_DEMUX *ossl_quic_channel_get0_demux(QUIC_CHANNEL *ch);
 255
 256 SSL *ossl_quic_channel_get0_ssl(QUIC_CHANNEL *ch);
 257
 258 /*
 259  * Retrieves a pointer to the channel mutex which was provided at the time the
 260  * channel was instantiated. In order to allow locks to be acquired and released
 261  * with the correct granularity, it is the caller's responsibility to ensure
 262  * this lock is held for write while calling any QUIC_CHANNEL method, except for
 263  * methods explicitly designed otherwise.
 264  *
 265  * This method is thread safe and does not require prior locking. It can also be
 266  * called while the lock is already held. Note that this is simply a convenience
 267  * function to access the mutex which was passed to the channel at instantiation
 268  * time; it does not belong to the channel but rather is presumed to belong to
 269  * the owner of the channel.
 270  */
 271 CRYPTO_MUTEX *ossl_quic_channel_get_mutex(QUIC_CHANNEL *ch);
 272
 273 /*
 274  * Creates a new locally-initiated stream in the stream mapper, choosing an
 275  * appropriate stream ID. If is_uni is 1, creates a unidirectional stream, else
 276  * creates a bidirectional stream. Returns NULL on failure.
 277  */
 278 QUIC_STREAM *ossl_quic_channel_new_stream_local(QUIC_CHANNEL *ch, int is_uni);
 279
 280 /*
 281  * Creates a new remotely-initiated stream in the stream mapper. The stream ID
 282  * is used to confirm the initiator and determine the stream type. The stream is
 283  * automatically added to the QSM's accept queue. A pointer to the stream is
 284  * also returned. Returns NULL on failure.
 285  */
 286 QUIC_STREAM *ossl_quic_channel_new_stream_remote(QUIC_CHANNEL *ch,
 287                                                  uint64_t stream_id);
 288
 289 # endif
 290
 291 #endif