| /* |
| * Copyright 2015-2020 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_CRYPTO_ASYNC_POSIX_H |
| #define OSSL_CRYPTO_ASYNC_POSIX_H |
| #include <openssl/e_os2.h> |
| |
| #if defined(OPENSSL_SYS_UNIX) \ |
| && defined(OPENSSL_THREADS) && !defined(OPENSSL_NO_ASYNC) \ |
| && !defined(__ANDROID__) && !defined(__OpenBSD__) |
| |
| # include <unistd.h> |
| |
| # if _POSIX_VERSION >= 200112L \ |
| && (_POSIX_VERSION < 200809L || defined(__GLIBC__)) |
| |
| # include <pthread.h> |
| |
| # define ASYNC_POSIX |
| # define ASYNC_ARCH |
| |
| # if defined(__CET__) || defined(__ia64__) |
| /* |
| * When Intel CET is enabled, makecontext will create a different |
| * shadow stack for each context. async_fibre_swapcontext cannot |
| * use _longjmp. It must call swapcontext to swap shadow stack as |
| * well as normal stack. |
| * On IA64 the register stack engine is not saved across setjmp/longjmp. Here |
| * swapcontext() performs correctly. |
| */ |
| # define USE_SWAPCONTEXT |
| # endif |
| # if defined(__aarch64__) && defined(__clang__) \ |
| && defined(__ARM_FEATURE_BTI_DEFAULT) && __ARM_FEATURE_BTI_DEFAULT == 1 |
| /* |
| * setjmp/longjmp don't currently work with BTI on all libc implementations |
| * when compiled by clang. This is because clang doesn't put a BTI after the |
| * call to setjmp where it returns the second time. This then fails on libc |
| * implementations - notably glibc - which use an indirect jump to there. |
| * So use the swapcontext implementation, which does work. |
| * See https://github.com/llvm/llvm-project/issues/48888. |
| */ |
| # define USE_SWAPCONTEXT |
| # endif |
| # include <ucontext.h> |
| # ifndef USE_SWAPCONTEXT |
| # include <setjmp.h> |
| # endif |
| |
| typedef struct async_fibre_st { |
| ucontext_t fibre; |
| # ifndef USE_SWAPCONTEXT |
| jmp_buf env; |
| int env_init; |
| # endif |
| } async_fibre; |
| |
| int async_local_init(void); |
| void async_local_deinit(void); |
| |
| static ossl_inline int async_fibre_swapcontext(async_fibre *o, async_fibre *n, int r) |
| { |
| # ifdef USE_SWAPCONTEXT |
| swapcontext(&o->fibre, &n->fibre); |
| # else |
| o->env_init = 1; |
| |
| if (!r || !_setjmp(o->env)) { |
| if (n->env_init) |
| _longjmp(n->env, 1); |
| else |
| setcontext(&n->fibre); |
| } |
| # endif |
| |
| return 1; |
| } |
| |
| # define async_fibre_init_dispatcher(d) |
| |
| int async_fibre_makecontext(async_fibre *fibre); |
| void async_fibre_free(async_fibre *fibre); |
| |
| # endif |
| #endif |
| #endif /* OSSL_CRYPTO_ASYNC_POSIX_H */ |