diff options
| -rw-r--r-- | include/internal/quic_thread_assist.h | 97 | ||||
| -rw-r--r-- | ssl/build.info | 9 | ||||
| -rw-r--r-- | ssl/quic/build.info | 1 | ||||
| -rw-r--r-- | ssl/quic/quic_thread_assist.c | 150 |
4 files changed, 257 insertions, 0 deletions
diff --git a/include/internal/quic_thread_assist.h b/include/internal/quic_thread_assist.h new file mode 100644 index 0000000000..94fcaec004 --- /dev/null +++ b/include/internal/quic_thread_assist.h @@ -0,0 +1,97 @@ +/* + * Copyright 2023 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the Apache License 2.0 (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html + */ + +#ifndef OSSL_QUIC_THREAD_ASSIST_H +# define OSSL_QUIC_THREAD_ASSIST_H + +# include <openssl/ssl.h> +# include "internal/thread.h" + +# if defined(OPENSSL_NO_QUIC) || defined(OPENSSL_NO_THREAD_POOL) +# define OPENSSL_NO_QUIC_THREAD_ASSIST +# endif + +# ifndef OPENSSL_NO_QUIC_THREAD_ASSIST + +/* + * QUIC Thread Assisted Functionality + * ================================== + * + * Where OS threading support is available, QUIC can optionally support a thread + * assisted mode of operation. The purpose of this mode of operation is to + * ensure that assorted timeout events which QUIC expects to be handled in a + * timely manner can be handled without the application needing to ensure that + * SSL_tick() is called on time. This is not needed if the application always + * has a call blocking to SSL_read() or SSL_write() (or another I/O function) on + * a QUIC SSL object, but if the application goes for long periods of time + * without makingany such call to a QUIC SSL object, libssl cannot ordinarily + * guarantee that QUIC timeout events will be serviced in a timely fashion. + * Thread assisted mode is therefore of use to applications which do not always + * have an ongoing call to an I/O function on a QUIC SSL object but also do not + * want to have to arrange periodic ticking. + * + * A consequence of this is that the intrusiveness of thread assisted mode upon + * the general architecture of our QUIC engine is actually fairly limited and + * amounts to an automatic ticking of the QUIC engine when timeouts expire, + * synchronised correctly with an application's own threads using locking. + */ +typedef struct quic_thread_assist_st { + QUIC_CHANNEL *ch; + CRYPTO_CONDVAR *cv; + CRYPTO_THREAD *t; + int teardown, joined; +} QUIC_THREAD_ASSIST; + +/* + * Initialise the thread assist object. The channel must have a valid mutex + * configured on it which will be retrieved automatically. It is assumed that + * the mutex is currently held when this function is called. This function does + * not affect the state of the mutex. + */ +int ossl_quic_thread_assist_init_start(QUIC_THREAD_ASSIST *qta, + QUIC_CHANNEL *ch); + +/* + * Request the thread assist helper to begin stopping the assist thread. This + * returns before the teardown is complete. Idempotent; multiple calls to this + * function are inconsequential. + * + * Precondition: channel mutex must be held (unchecked) + */ +int ossl_quic_thread_assist_stop_async(QUIC_THREAD_ASSIST *qta); + +/* + * Wait until the thread assist helper is torn down. This automatically implies + * the effects of ossl_quic_thread_assist_stop_async(). Returns immediately + * if the teardown has already completed. + * + * Precondition: channel mutex must be held (unchecked) + */ +int ossl_quic_thread_assist_wait_stopped(QUIC_THREAD_ASSIST *qta); + +/* + * Deallocates state associated with the thread assist helper. + * ossl_quic_thread_assist_wait_stopped() must have returned successfully before + * calling this. It does not matter whether the channel mutex is held or not. + * + * Precondition: ossl_quic_thread_assist_wait_stopped() has returned 1 + * (asserted) + */ +int ossl_quic_thread_assist_cleanup(QUIC_THREAD_ASSIST *qta); + +/* + * Must be called to notify the assist thread if the channel deadline changes. + * + * Precondition: channel mutex must be held (unchecked) + */ +int ossl_quic_thread_assist_notify_deadline_changed(QUIC_THREAD_ASSIST *qta); + +# endif + +#endif diff --git a/ssl/build.info b/ssl/build.info index 00e9e8fd7d..4b43a4ce01 100644 --- a/ssl/build.info +++ b/ssl/build.info @@ -33,4 +33,13 @@ ENDIF IF[{- !$disabled{quic} -}] SOURCE[../libssl]=priority_queue.c event_queue.c + + IF[{- !$disabled{'thread-pool'} -}] + SHARED_SOURCE[../libssl]=\ + ../crypto/thread/arch/thread_posix.c \ + ../crypto/thread/arch/thread_win.c \ + ../crypto/thread/arch/thread_none.c \ + ../crypto/thread/arch.c + ENDIF + ENDIF diff --git a/ssl/quic/build.info b/ssl/quic/build.info index 79aa00dbba..edd2c76d1e 100644 --- a/ssl/quic/build.info +++ b/ssl/quic/build.info @@ -12,3 +12,4 @@ SOURCE[$LIBSSL]=quic_reactor.c SOURCE[$LIBSSL]=quic_channel.c SOURCE[$LIBSSL]=quic_tserver.c SOURCE[$LIBSSL]=quic_tls.c +SOURCE[$LIBSSL]=quic_thread_assist.c diff --git a/ssl/quic/quic_thread_assist.c b/ssl/quic/quic_thread_assist.c new file mode 100644 index 0000000000..6b2c219982 --- /dev/null +++ b/ssl/quic/quic_thread_assist.c @@ -0,0 +1,150 @@ +/* + * Copyright 2023 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the Apache License 2.0 (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html + */ + +#include <openssl/macros.h> +#include "quic_local.h" +#include "internal/time.h" +#include "internal/thread.h" +#include "internal/thread_arch.h" +#include "internal/quic_thread_assist.h" + +#if !defined(OPENSSL_NO_QUIC) && !defined(OPENSSL_NO_THREAD_POOL) + +/* Main loop for the QUIC assist thread. */ +static unsigned int assist_thread_main(void *arg) +{ + QUIC_THREAD_ASSIST *qta = arg; + CRYPTO_MUTEX *m = ossl_quic_channel_get_mutex(qta->ch); + QUIC_REACTOR *rtor; + + if (!CRYPTO_THREAD_write_lock(m)) + return 0; + + rtor = ossl_quic_channel_get_reactor(qta->ch); + + for (;;) { + if (qta->teardown) + break; + + ossl_crypto_condvar_wait_timeout(qta->cv, m, + ossl_quic_reactor_get_tick_deadline(rtor)); + + /* + * We have now been woken up. This can be for one of the following + * reasons: + * + * - We have been asked to teardown (qta->teardown is set); + * - The tick deadline has passed. + * - The tick deadline has changed. + * + * For robustness, this loop also handles spurious wakeups correctly + * (which does not require any extra code). + */ + if (qta->teardown) + break; + + ossl_quic_reactor_tick(rtor); + } + + CRYPTO_THREAD_unlock(m); + return 1; +} + +int ossl_quic_thread_assist_init_start(QUIC_THREAD_ASSIST *qta, + QUIC_CHANNEL *ch) +{ + CRYPTO_MUTEX *mutex = ossl_quic_channel_get_mutex(ch); + + if (mutex == NULL) + return 0; + + qta->ch = ch; + qta->teardown = 0; + qta->joined = 0; + + qta->cv = ossl_crypto_condvar_new(); + if (qta->cv == NULL) + return 0; + + qta->t = ossl_crypto_thread_native_start(assist_thread_main, + qta, /*joinable=*/1); + if (qta->t == NULL) { + ossl_crypto_condvar_free(qta->cv); + return 0; + } + + return 1; +} + +int ossl_quic_thread_assist_stop_async(QUIC_THREAD_ASSIST *qta) +{ + if (!qta->teardown) { + qta->teardown = 1; + ossl_crypto_condvar_broadcast(qta->cv); + } + + return 1; +} + +static void ignore_res(int x) {} + +int ossl_quic_thread_assist_wait_stopped(QUIC_THREAD_ASSIST *qta) +{ + CRYPTO_THREAD_RETVAL rv; + CRYPTO_RWLOCK *m = ossl_quic_channel_get_mutex(qta->ch); + + if (qta->joined) + return 1; + + if (!ossl_quic_thread_assist_stop_async(qta)) + return 0; + + CRYPTO_THREAD_unlock(m); + + if (!ossl_crypto_thread_native_join(qta->t, &rv)) { + ignore_res(CRYPTO_THREAD_write_lock(m)); /* best effort */ + return 0; + } + + qta->joined = 1; + + if (!CRYPTO_THREAD_write_lock(m)) + return 0; + + return 1; +} + +int ossl_quic_thread_assist_cleanup(QUIC_THREAD_ASSIST *qta) +{ + if (!ossl_assert(qta->joined)) + return 0; + + ossl_crypto_condvar_free(qta->cv); + ossl_crypto_thread_native_clean(qta->t); + + qta->ch = NULL; + qta->cv = NULL; + qta->t = NULL; + return 1; +} + +int ossl_quic_thread_assist_notify_deadline_changed(QUIC_THREAD_ASSIST *qta) +{ + if (qta->teardown) + return 0; + + /* + * Wake-one would be better here but as there is only one listening thread + * this does not actually matter. + */ + ossl_crypto_condvar_broadcast(qta->cv); + return 1; +} + +#endif |