| /* |
| * Copyright (C) 2020 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include <async_safe/log.h> |
| |
| #include "bionic/pthread_internal.h" |
| #include "native_bridge_support/linker/static_tls_config.h" |
| #include "private/KernelArgumentBlock.h" |
| #include "private/bionic_arc4random.h" |
| #include "private/bionic_elf_tls.h" |
| #include "private/bionic_globals.h" |
| #include "private/bionic_ssp.h" |
| #include "private/bionic_tls.h" |
| |
| // Once the loader has calculated the size of static TLS, report the information |
| // to the host so it can allocate the static TLS of future threads. |
| extern "C" void __native_bridge_config_static_tls(const NativeBridgeStaticTlsConfig* config); |
| |
| // Get the current thread's host pthread_internal_t. |
| extern "C" pthread_t __native_bridge_get_host_pthread(); |
| |
| // The host has already initialized the thread and created its |
| // pthread_internal_t object. The guest needs to initialize its globals and the |
| // main thread's guest static TLS memory. |
| extern "C" void __libc_init_main_thread_early(const KernelArgumentBlock& args, |
| bionic_tcb* temp_tcb) { |
| __libc_shared_globals()->auxv = args.auxv; |
| #if defined(__i386__) |
| __libc_init_sysinfo(); |
| #endif |
| // TCB layout is different between host and guest, so initialize the guest |
| // TCB. Reuse the host's pthread_internal_t and bionic_tls objects. |
| auto host_thread = reinterpret_cast<pthread_internal_t*>(__native_bridge_get_host_pthread()); |
| __init_tcb(temp_tcb, host_thread); |
| __set_tls(&temp_tcb->tls_slot(0)); |
| } |
| |
| extern "C" void __libc_init_main_thread_late() { |
| // Reuse the host's bionic_tls structure. |
| __get_tls()[TLS_SLOT_BIONIC_TLS] = __get_thread()->bionic_tls; |
| |
| // There's currently no way for the guest to query the host's stack guard |
| // cookie, so just generate a new one. |
| __libc_safe_arc4random_buf(&__stack_chk_guard, sizeof(__stack_chk_guard)); |
| __init_tcb_stack_guard(__get_bionic_tcb()); |
| } |
| |
| extern "C" void __libc_init_main_thread_final() { |
| const StaticTlsLayout& layout = __libc_shared_globals()->static_tls_layout; |
| |
| // Prepare the initialization image for the host. |
| char* init_img = new char[layout.size()]{}; |
| __init_static_tls(init_img); |
| bionic_tcb img_tcb = {}; |
| __init_tcb_dtv(&img_tcb); |
| __init_tcb_stack_guard(&img_tcb); |
| memcpy(init_img + layout.offset_bionic_tcb(), &img_tcb, sizeof(img_tcb)); |
| |
| // Configure the host to create guest static TLS memory for new threads. The |
| // host will replace the guest main thread's static TLS with memory it |
| // allocates. |
| NativeBridgeStaticTlsConfig config{}; |
| config.size = layout.size(); |
| config.tpoff = layout.offset_thread_pointer(); |
| config.tls_slot_thread_id = TLS_SLOT_THREAD_ID; |
| config.tls_slot_bionic_tls = TLS_SLOT_BIONIC_TLS; |
| config.init_img = init_img; |
| __native_bridge_config_static_tls(&config); |
| } |