Source code
Revision control
Copy as Markdown
Other Tools
/*
* OS and machine specific utility functions
* (C) 2015,2016,2017,2018 Jack Lloyd
* (C) 2016 Daniel Neus
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/internal/os_utils.h>
#include <botan/exceptn.h>
#include <botan/mem_ops.h>
#include <botan/internal/target_info.h>
#if defined(BOTAN_HAS_CPUID)
#include <botan/internal/cpuid.h>
#endif
#include <algorithm>
#include <chrono>
#include <cstdlib>
#include <iomanip>
#include <sstream>
#if defined(BOTAN_TARGET_OS_HAS_POSIX1)
#include <errno.h>
#include <pthread.h>
#include <setjmp.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <sys/types.h>
#include <termios.h>
#include <unistd.h>
#undef B0
#endif
#if defined(BOTAN_TARGET_OS_IS_EMSCRIPTEN)
#include <emscripten/emscripten.h>
#endif
#if defined(BOTAN_TARGET_OS_HAS_GETAUXVAL) || defined(BOTAN_TARGET_OS_HAS_ELF_AUX_INFO)
#include <sys/auxv.h>
#endif
#if defined(BOTAN_TARGET_OS_HAS_WIN32)
#define NOMINMAX 1
#define _WINSOCKAPI_ // stop windows.h including winsock.h
#include <windows.h>
#if defined(BOTAN_BUILD_COMPILER_IS_MSVC)
#include <libloaderapi.h>
#include <stringapiset.h>
#endif
#endif
#if defined(BOTAN_TARGET_OS_IS_IOS) || defined(BOTAN_TARGET_OS_IS_MACOS)
#include <mach/vm_statistics.h>
#include <sys/sysctl.h>
#include <sys/types.h>
#endif
#if defined(BOTAN_TARGET_OS_HAS_PRCTL)
#include <sys/prctl.h>
#endif
#if defined(BOTAN_TARGET_OS_IS_FREEBSD) || defined(BOTAN_TARGET_OS_IS_OPENBSD) || defined(BOTAN_TARGET_OS_IS_DRAGONFLY)
#include <pthread_np.h>
#endif
#if defined(BOTAN_TARGET_OS_IS_HAIKU)
#include <kernel/OS.h>
#endif
namespace Botan {
uint32_t OS::get_process_id() {
#if defined(BOTAN_TARGET_OS_HAS_POSIX1)
return ::getpid();
#elif defined(BOTAN_TARGET_OS_HAS_WIN32)
return ::GetCurrentProcessId();
#elif defined(BOTAN_TARGET_OS_IS_LLVM) || defined(BOTAN_TARGET_OS_IS_NONE)
return 0; // truly no meaningful value
#else
#error "Missing get_process_id"
#endif
}
namespace {
#if defined(BOTAN_TARGET_OS_HAS_GETAUXVAL) || defined(BOTAN_TARGET_OS_HAS_ELF_AUX_INFO)
#define BOTAN_TARGET_HAS_AUXVAL_INTERFACE
#endif
std::optional<unsigned long> auxval_hwcap() {
#if defined(AT_HWCAP)
return AT_HWCAP;
#elif defined(BOTAN_TARGET_HAS_AUXVAL_INTERFACE)
// If the value is not defined in a header we can see,
// but auxval is supported, return the Linux/Android value
return 16;
#else
return {};
#endif
}
std::optional<unsigned long> auxval_hwcap2() {
#if defined(AT_HWCAP2)
return AT_HWCAP2;
#elif defined(BOTAN_TARGET_HAS_AUXVAL_INTERFACE)
// If the value is not defined in a header we can see,
// but auxval is supported, return the Linux/Android value
return 26;
#else
return {};
#endif
}
std::optional<unsigned long> get_auxval(std::optional<unsigned long> id) {
if(id) {
#if defined(BOTAN_TARGET_OS_HAS_GETAUXVAL)
return ::getauxval(*id);
#elif defined(BOTAN_TARGET_OS_HAS_ELF_AUX_INFO)
unsigned long auxinfo = 0;
if(::elf_aux_info(static_cast<int>(*id), &auxinfo, sizeof(auxinfo)) == 0) {
return auxinfo;
}
#endif
}
return {};
}
} // namespace
std::optional<std::pair<unsigned long, unsigned long>> OS::get_auxval_hwcap() {
if(const auto hwcap = get_auxval(auxval_hwcap())) {
// If hwcap worked/was valid, we don't require hwcap2 to also
// succeed but instead will return zeros if it failed.
auto hwcap2 = get_auxval(auxval_hwcap2()).value_or(0);
return std::make_pair(*hwcap, hwcap2);
} else {
return {};
}
}
namespace {
/**
* Test if we are currently running with elevated permissions
* eg setuid, setgid, or with POSIX caps set.
*/
bool running_in_privileged_state() {
#if defined(AT_SECURE)
if(auto at_secure = get_auxval(AT_SECURE)) {
return at_secure != 0;
}
#endif
#if defined(BOTAN_TARGET_OS_HAS_POSIX1)
return (::getuid() != ::geteuid()) || (::getgid() != ::getegid());
#else
return false;
#endif
}
} // namespace
uint64_t OS::get_cpu_cycle_counter() {
uint64_t rtc = 0;
#if defined(BOTAN_TARGET_OS_HAS_WIN32)
LARGE_INTEGER tv;
::QueryPerformanceCounter(&tv);
rtc = tv.QuadPart;
#elif defined(BOTAN_USE_GCC_INLINE_ASM)
#if defined(BOTAN_TARGET_ARCH_IS_X86_64)
uint32_t rtc_low = 0, rtc_high = 0;
asm volatile("rdtsc" : "=d"(rtc_high), "=a"(rtc_low));
rtc = (static_cast<uint64_t>(rtc_high) << 32) | rtc_low;
#elif defined(BOTAN_TARGET_CPU_IS_X86_FAMILY) && defined(BOTAN_HAS_CPUID)
if(CPUID::has(CPUID::Feature::RDTSC)) {
uint32_t rtc_low = 0, rtc_high = 0;
asm volatile("rdtsc" : "=d"(rtc_high), "=a"(rtc_low));
rtc = (static_cast<uint64_t>(rtc_high) << 32) | rtc_low;
}
#elif defined(BOTAN_TARGET_ARCH_IS_PPC64)
for(;;) {
uint32_t rtc_low = 0, rtc_high = 0, rtc_high2 = 0;
asm volatile("mftbu %0" : "=r"(rtc_high));
asm volatile("mftb %0" : "=r"(rtc_low));
asm volatile("mftbu %0" : "=r"(rtc_high2));
if(rtc_high == rtc_high2) {
rtc = (static_cast<uint64_t>(rtc_high) << 32) | rtc_low;
break;
}
}
#elif defined(BOTAN_TARGET_ARCH_IS_ALPHA)
asm volatile("rpcc %0" : "=r"(rtc));
// OpenBSD does not trap access to the %tick register
#elif defined(BOTAN_TARGET_ARCH_IS_SPARC64) && !defined(BOTAN_TARGET_OS_IS_OPENBSD)
asm volatile("rd %%tick, %0" : "=r"(rtc));
#elif defined(BOTAN_TARGET_ARCH_IS_IA64)
asm volatile("mov %0=ar.itc" : "=r"(rtc));
#elif defined(BOTAN_TARGET_ARCH_IS_S390X)
asm volatile("stck 0(%0)" : : "a"(&rtc) : "memory", "cc");
#elif defined(BOTAN_TARGET_ARCH_IS_HPPA)
asm volatile("mfctl 16,%0" : "=r"(rtc)); // 64-bit only?
#else
//#warning "OS::get_cpu_cycle_counter not implemented"
#endif
#endif
return rtc;
}
size_t OS::get_cpu_available() {
#if defined(BOTAN_TARGET_OS_HAS_POSIX1)
#if defined(_SC_NPROCESSORS_ONLN)
const long cpu_online = ::sysconf(_SC_NPROCESSORS_ONLN);
if(cpu_online > 0) {
return static_cast<size_t>(cpu_online);
}
#endif
#if defined(_SC_NPROCESSORS_CONF)
const long cpu_conf = ::sysconf(_SC_NPROCESSORS_CONF);
if(cpu_conf > 0) {
return static_cast<size_t>(cpu_conf);
}
#endif
#endif
#if defined(BOTAN_TARGET_OS_HAS_THREADS)
// hardware_concurrency is allowed to return 0 if the value is not
// well defined or not computable.
const size_t hw_concur = std::thread::hardware_concurrency();
if(hw_concur > 0) {
return hw_concur;
}
#endif
return 1;
}
uint64_t OS::get_high_resolution_clock() {
if(uint64_t cpu_clock = OS::get_cpu_cycle_counter()) {
return cpu_clock;
}
#if defined(BOTAN_TARGET_OS_IS_EMSCRIPTEN)
return emscripten_get_now();
#endif
/*
If we got here either we either don't have an asm instruction
above, or (for x86) RDTSC is not available at runtime. Try some
clock_gettimes and return the first one that works, or otherwise
fall back to std::chrono.
*/
#if defined(BOTAN_TARGET_OS_HAS_CLOCK_GETTIME)
// The ordering here is somewhat arbitrary...
const clockid_t clock_types[] = {
#if defined(CLOCK_MONOTONIC_HR)
CLOCK_MONOTONIC_HR,
#endif
#if defined(CLOCK_MONOTONIC_RAW)
CLOCK_MONOTONIC_RAW,
#endif
#if defined(CLOCK_MONOTONIC)
CLOCK_MONOTONIC,
#endif
#if defined(CLOCK_PROCESS_CPUTIME_ID)
CLOCK_PROCESS_CPUTIME_ID,
#endif
#if defined(CLOCK_THREAD_CPUTIME_ID)
CLOCK_THREAD_CPUTIME_ID,
#endif
};
for(clockid_t clock : clock_types) {
struct timespec ts;
if(::clock_gettime(clock, &ts) == 0) {
return (static_cast<uint64_t>(ts.tv_sec) * 1000000000) + static_cast<uint64_t>(ts.tv_nsec);
}
}
#endif
#if defined(BOTAN_TARGET_OS_HAS_SYSTEM_CLOCK)
// Plain C++11 fallback
auto now = std::chrono::high_resolution_clock::now().time_since_epoch();
return std::chrono::duration_cast<std::chrono::nanoseconds>(now).count();
#else
return 0;
#endif
}
uint64_t OS::get_system_timestamp_ns() {
#if defined(BOTAN_TARGET_OS_HAS_CLOCK_GETTIME)
struct timespec ts;
if(::clock_gettime(CLOCK_REALTIME, &ts) == 0) {
return (static_cast<uint64_t>(ts.tv_sec) * 1000000000) + static_cast<uint64_t>(ts.tv_nsec);
}
#endif
#if defined(BOTAN_TARGET_OS_HAS_SYSTEM_CLOCK)
auto now = std::chrono::system_clock::now().time_since_epoch();
return std::chrono::duration_cast<std::chrono::nanoseconds>(now).count();
#else
throw Not_Implemented("OS::get_system_timestamp_ns this system does not support a clock");
#endif
}
std::string OS::format_time(time_t time, const std::string& format) {
std::tm tm;
#if defined(BOTAN_TARGET_OS_HAS_WIN32)
localtime_s(&tm, &time);
#elif defined(BOTAN_TARGET_OS_HAS_POSIX1)
localtime_r(&time, &tm);
#else
if(auto tmp = std::localtime(&time)) {
tm = *tmp;
} else {
throw Encoding_Error("Could not convert time_t to localtime");
}
#endif
std::ostringstream oss;
oss << std::put_time(&tm, format.c_str());
return oss.str();
}
size_t OS::system_page_size() {
const size_t default_page_size = 4096;
#if defined(BOTAN_TARGET_OS_HAS_POSIX1)
long p = ::sysconf(_SC_PAGESIZE);
if(p > 1) {
return static_cast<size_t>(p);
} else {
return default_page_size;
}
#elif defined(BOTAN_TARGET_OS_HAS_VIRTUAL_LOCK)
BOTAN_UNUSED(default_page_size);
SYSTEM_INFO sys_info;
::GetSystemInfo(&sys_info);
return sys_info.dwPageSize;
#else
return default_page_size;
#endif
}
size_t OS::get_memory_locking_limit() {
/*
* Linux defaults to only 64 KiB of mlockable memory per process (too small)
* but BSDs offer a small fraction of total RAM (more than we need). Bound the
* total mlock size to 512 KiB which is enough to run the entire test suite
* without spilling to non-mlock memory (and thus presumably also enough for
* many useful programs), but small enough that we should not cause problems
* even if many processes are mlocking on the same machine.
*/
const size_t max_locked_kb = 512;
/*
* If RLIMIT_MEMLOCK is not defined, likely the OS does not support
* unprivileged mlock calls.
*/
#if defined(RLIMIT_MEMLOCK) && defined(BOTAN_TARGET_OS_HAS_POSIX1) && defined(BOTAN_TARGET_OS_HAS_POSIX_MLOCK)
const size_t mlock_requested =
std::min<size_t>(read_env_variable_sz("BOTAN_MLOCK_POOL_SIZE", max_locked_kb), max_locked_kb);
if(mlock_requested > 0) {
struct ::rlimit limits;
::getrlimit(RLIMIT_MEMLOCK, &limits);
if(limits.rlim_cur < limits.rlim_max) {
limits.rlim_cur = limits.rlim_max;
::setrlimit(RLIMIT_MEMLOCK, &limits);
::getrlimit(RLIMIT_MEMLOCK, &limits);
}
return std::min<size_t>(limits.rlim_cur, mlock_requested * 1024);
}
#elif defined(BOTAN_TARGET_OS_HAS_VIRTUAL_LOCK)
const size_t mlock_requested =
std::min<size_t>(read_env_variable_sz("BOTAN_MLOCK_POOL_SIZE", max_locked_kb), max_locked_kb);
SIZE_T working_min = 0, working_max = 0;
if(!::GetProcessWorkingSetSize(::GetCurrentProcess(), &working_min, &working_max)) {
return 0;
}
// According to Microsoft MSDN:
// The maximum number of pages that a process can lock is equal to the number of pages in its minimum working set minus a small overhead
// In the book "Windows Internals Part 2": the maximum lockable pages are minimum working set size - 8 pages
// But the information in the book seems to be inaccurate/outdated
// I've tested this on Windows 8.1 x64, Windows 10 x64 and Windows 7 x86
// On all three OS the value is 11 instead of 8
const size_t overhead = OS::system_page_size() * 11;
if(working_min > overhead) {
const size_t lockable_bytes = working_min - overhead;
return std::min<size_t>(lockable_bytes, mlock_requested * 1024);
}
#else
// Not supported on this platform
BOTAN_UNUSED(max_locked_kb);
#endif
return 0;
}
bool OS::read_env_variable(std::string& value_out, std::string_view name_view) {
value_out = "";
if(running_in_privileged_state()) {
return false;
}
#if defined(BOTAN_TARGET_OS_HAS_WIN32) && defined(BOTAN_BUILD_COMPILER_IS_MSVC)
const std::string name(name_view);
char val[128] = {0};
size_t req_size = 0;
if(getenv_s(&req_size, val, sizeof(val), name.c_str()) == 0) {
// Microsoft's implementation always writes a terminating \0,
// and includes it in the reported length of the environment variable
// if a value exists.
if(req_size > 0 && val[req_size - 1] == '\0') {
value_out = std::string(val);
} else {
value_out = std::string(val, req_size);
}
return true;
}
#else
const std::string name(name_view);
if(const char* val = std::getenv(name.c_str())) {
value_out = val;
return true;
}
#endif
return false;
}
size_t OS::read_env_variable_sz(std::string_view name, size_t def) {
std::string value;
if(read_env_variable(value, name) && !value.empty()) {
try {
const size_t val = std::stoul(value, nullptr);
return val;
} catch(std::exception&) { /* ignore it */
}
}
return def;
}
#if defined(BOTAN_TARGET_OS_HAS_POSIX1) && defined(BOTAN_TARGET_OS_HAS_POSIX_MLOCK)
namespace {
int get_locked_fd() {
#if defined(BOTAN_TARGET_OS_IS_IOS) || defined(BOTAN_TARGET_OS_IS_MACOS)
// On Darwin, tagging anonymous pages allows vmmap to track these.
// Allowed from 240 to 255 for userland applications
static constexpr int default_locked_fd = 255;
int locked_fd = default_locked_fd;
if(size_t locked_fdl = OS::read_env_variable_sz("BOTAN_LOCKED_FD", default_locked_fd)) {
if(locked_fdl < 240 || locked_fdl > 255) {
locked_fdl = default_locked_fd;
}
locked_fd = static_cast<int>(locked_fdl);
}
return VM_MAKE_TAG(locked_fd);
#else
return -1;
#endif
}
} // namespace
#endif
std::vector<void*> OS::allocate_locked_pages(size_t count) {
std::vector<void*> result;
#if(defined(BOTAN_TARGET_OS_HAS_POSIX1) && defined(BOTAN_TARGET_OS_HAS_POSIX_MLOCK)) || \
defined(BOTAN_TARGET_OS_HAS_VIRTUAL_LOCK)
result.reserve(count);
const size_t page_size = OS::system_page_size();
#if defined(BOTAN_TARGET_OS_HAS_POSIX1) && defined(BOTAN_TARGET_OS_HAS_POSIX_MLOCK)
static const int locked_fd = get_locked_fd();
#endif
for(size_t i = 0; i != count; ++i) {
void* ptr = nullptr;
#if defined(BOTAN_TARGET_OS_HAS_POSIX1) && defined(BOTAN_TARGET_OS_HAS_POSIX_MLOCK)
int mmap_flags = MAP_PRIVATE;
#if defined(MAP_ANONYMOUS)
mmap_flags |= MAP_ANONYMOUS;
#elif defined(MAP_ANON)
mmap_flags |= MAP_ANON;
#endif
#if defined(MAP_CONCEAL)
mmap_flags |= MAP_CONCEAL;
#elif defined(MAP_NOCORE)
mmap_flags |= MAP_NOCORE;
#endif
int mmap_prot = PROT_READ | PROT_WRITE;
#if defined(PROT_MAX)
mmap_prot |= PROT_MAX(mmap_prot);
#endif
ptr = ::mmap(nullptr,
3 * page_size,
mmap_prot,
mmap_flags,
/*fd=*/locked_fd,
/*offset=*/0);
if(ptr == MAP_FAILED) {
continue;
}
// lock the data page
if(::mlock(static_cast<uint8_t*>(ptr) + page_size, page_size) != 0) {
::munmap(ptr, 3 * page_size);
continue;
}
#if defined(MADV_DONTDUMP)
// we ignore errors here, as DONTDUMP is just a bonus
::madvise(static_cast<uint8_t*>(ptr) + page_size, page_size, MADV_DONTDUMP);
#endif
#elif defined(BOTAN_TARGET_OS_HAS_VIRTUAL_LOCK)
ptr = ::VirtualAlloc(nullptr, 3 * page_size, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);
if(ptr == nullptr)
continue;
if(::VirtualLock(static_cast<uint8_t*>(ptr) + page_size, page_size) == 0) {
::VirtualFree(ptr, 0, MEM_RELEASE);
continue;
}
#endif
std::memset(ptr, 0, 3 * page_size); // zero data page and both guard pages
// Attempts to name the data page
page_named(ptr, 3 * page_size);
// Make guard page preceeding the data page
page_prohibit_access(static_cast<uint8_t*>(ptr));
// Make guard page following the data page
page_prohibit_access(static_cast<uint8_t*>(ptr) + 2 * page_size);
result.push_back(static_cast<uint8_t*>(ptr) + page_size);
}
#else
BOTAN_UNUSED(count);
#endif
return result;
}
void OS::page_allow_access(void* page) {
#if defined(BOTAN_TARGET_OS_HAS_POSIX1)
const size_t page_size = OS::system_page_size();
::mprotect(page, page_size, PROT_READ | PROT_WRITE);
#elif defined(BOTAN_TARGET_OS_HAS_VIRTUAL_LOCK)
const size_t page_size = OS::system_page_size();
DWORD old_perms = 0;
::VirtualProtect(page, page_size, PAGE_READWRITE, &old_perms);
BOTAN_UNUSED(old_perms);
#else
BOTAN_UNUSED(page);
#endif
}
void OS::page_prohibit_access(void* page) {
#if defined(BOTAN_TARGET_OS_HAS_POSIX1)
const size_t page_size = OS::system_page_size();
::mprotect(page, page_size, PROT_NONE);
#elif defined(BOTAN_TARGET_OS_HAS_VIRTUAL_LOCK)
const size_t page_size = OS::system_page_size();
DWORD old_perms = 0;
::VirtualProtect(page, page_size, PAGE_NOACCESS, &old_perms);
BOTAN_UNUSED(old_perms);
#else
BOTAN_UNUSED(page);
#endif
}
void OS::free_locked_pages(const std::vector<void*>& pages) {
const size_t page_size = OS::system_page_size();
for(size_t i = 0; i != pages.size(); ++i) {
void* ptr = pages[i];
secure_scrub_memory(ptr, page_size);
// ptr points to the data page, guard pages are before and after
page_allow_access(static_cast<uint8_t*>(ptr) - page_size);
page_allow_access(static_cast<uint8_t*>(ptr) + page_size);
#if defined(BOTAN_TARGET_OS_HAS_POSIX1) && defined(BOTAN_TARGET_OS_HAS_POSIX_MLOCK)
::munlock(ptr, page_size);
::munmap(static_cast<uint8_t*>(ptr) - page_size, 3 * page_size);
#elif defined(BOTAN_TARGET_OS_HAS_VIRTUAL_LOCK)
::VirtualUnlock(ptr, page_size);
::VirtualFree(static_cast<uint8_t*>(ptr) - page_size, 0, MEM_RELEASE);
#endif
}
}
void OS::page_named(void* page, size_t size) {
#if defined(BOTAN_TARGET_OS_HAS_PRCTL) && defined(PR_SET_VMA) && defined(PR_SET_VMA_ANON_NAME)
static constexpr char name[] = "Botan mlock pool";
int r = prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, reinterpret_cast<uintptr_t>(page), size, name);
BOTAN_UNUSED(r);
#else
BOTAN_UNUSED(page, size);
#endif
}
#if defined(BOTAN_TARGET_OS_HAS_THREADS)
void OS::set_thread_name(std::thread& thread, const std::string& name) {
#if defined(BOTAN_TARGET_OS_IS_LINUX) || defined(BOTAN_TARGET_OS_IS_FREEBSD) || defined(BOTAN_TARGET_OS_IS_DRAGONFLY)
static_cast<void>(pthread_setname_np(thread.native_handle(), name.c_str()));
#elif defined(BOTAN_TARGET_OS_IS_OPENBSD)
static_cast<void>(pthread_set_name_np(thread.native_handle(), name.c_str()));
#elif defined(BOTAN_TARGET_OS_IS_NETBSD)
static_cast<void>(pthread_setname_np(thread.native_handle(), "%s", const_cast<char*>(name.c_str())));
#elif defined(BOTAN_TARGET_OS_HAS_WIN32) && defined(_LIBCPP_HAS_THREAD_API_PTHREAD)
static_cast<void>(pthread_setname_np(thread.native_handle(), name.c_str()));
#elif defined(BOTAN_TARGET_OS_HAS_WIN32) && defined(BOTAN_BUILD_COMPILER_IS_MSVC)
typedef HRESULT(WINAPI * std_proc)(HANDLE, PCWSTR);
HMODULE kern = GetModuleHandleA("KernelBase.dll");
std_proc set_thread_name = reinterpret_cast<std_proc>(GetProcAddress(kern, "SetThreadDescription"));
if(set_thread_name) {
std::wstring w;
auto sz = MultiByteToWideChar(CP_UTF8, 0, name.data(), -1, nullptr, 0);
if(sz > 0) {
w.resize(sz);
if(MultiByteToWideChar(CP_UTF8, 0, name.data(), -1, &w[0], sz) > 0) {
(void)set_thread_name(thread.native_handle(), w.c_str());
}
}
}
#elif defined(BOTAN_TARGET_OS_IF_HAIKU)
auto thread_id = get_pthread_thread_id(thread.native_handle());
static_cast<void>(rename_thread(thread_id, name.c_str()));
#else
// TODO other possible oses ?
// macOs does not seem to allow to name threads other than the current one.
BOTAN_UNUSED(thread, name);
#endif
}
#endif
#if defined(BOTAN_TARGET_OS_HAS_POSIX1) && !defined(BOTAN_TARGET_OS_IS_EMSCRIPTEN)
namespace {
// NOLINTNEXTLINE(*-avoid-non-const-global-variables)
::sigjmp_buf g_sigill_jmp_buf;
void botan_sigill_handler(int /*unused*/) {
siglongjmp(g_sigill_jmp_buf, /*non-zero return value*/ 1);
}
} // namespace
#endif
int OS::run_cpu_instruction_probe(const std::function<int()>& probe_fn) {
volatile int probe_result = -3;
#if defined(BOTAN_TARGET_OS_HAS_POSIX1) && !defined(BOTAN_TARGET_OS_IS_EMSCRIPTEN)
struct sigaction old_sigaction;
struct sigaction sigaction;
sigaction.sa_handler = botan_sigill_handler;
sigemptyset(&sigaction.sa_mask);
sigaction.sa_flags = 0;
int rc = ::sigaction(SIGILL, &sigaction, &old_sigaction);
if(rc != 0) {
throw System_Error("run_cpu_instruction_probe sigaction failed", errno);
}
rc = sigsetjmp(g_sigill_jmp_buf, /*save sigs*/ 1);
if(rc == 0) {
// first call to sigsetjmp
probe_result = probe_fn();
} else if(rc == 1) {
// non-local return from siglongjmp in signal handler: return error
probe_result = -1;
}
// Restore old SIGILL handler, if any
rc = ::sigaction(SIGILL, &old_sigaction, nullptr);
if(rc != 0) {
throw System_Error("run_cpu_instruction_probe sigaction restore failed", errno);
}
#else
BOTAN_UNUSED(probe_fn);
#endif
return probe_result;
}
std::unique_ptr<OS::Echo_Suppression> OS::suppress_echo_on_terminal() {
#if defined(BOTAN_TARGET_OS_HAS_POSIX1)
class POSIX_Echo_Suppression : public Echo_Suppression {
public:
POSIX_Echo_Suppression() {
m_stdin_fd = fileno(stdin);
if(::tcgetattr(m_stdin_fd, &m_old_termios) != 0) {
throw System_Error("Getting terminal status failed", errno);
}
struct termios noecho_flags = m_old_termios;
noecho_flags.c_lflag &= ~ECHO;
noecho_flags.c_lflag |= ECHONL;
if(::tcsetattr(m_stdin_fd, TCSANOW, &noecho_flags) != 0) {
throw System_Error("Clearing terminal echo bit failed", errno);
}
}
void reenable_echo() override {
if(m_stdin_fd > 0) {
if(::tcsetattr(m_stdin_fd, TCSANOW, &m_old_termios) != 0) {
throw System_Error("Restoring terminal echo bit failed", errno);
}
m_stdin_fd = -1;
}
}
~POSIX_Echo_Suppression() override {
try {
reenable_echo();
} catch(...) {}
}
POSIX_Echo_Suppression(const POSIX_Echo_Suppression& other) = delete;
POSIX_Echo_Suppression(POSIX_Echo_Suppression&& other) = delete;
POSIX_Echo_Suppression& operator=(const POSIX_Echo_Suppression& other) = delete;
POSIX_Echo_Suppression& operator=(POSIX_Echo_Suppression&& other) = delete;
private:
int m_stdin_fd;
struct termios m_old_termios;
};
return std::make_unique<POSIX_Echo_Suppression>();
#elif defined(BOTAN_TARGET_OS_HAS_WIN32)
class Win32_Echo_Suppression : public Echo_Suppression {
public:
Win32_Echo_Suppression() {
m_input_handle = ::GetStdHandle(STD_INPUT_HANDLE);
if(::GetConsoleMode(m_input_handle, &m_console_state) == 0)
throw System_Error("Getting console mode failed", ::GetLastError());
DWORD new_mode = ENABLE_LINE_INPUT | ENABLE_PROCESSED_INPUT;
if(::SetConsoleMode(m_input_handle, new_mode) == 0)
throw System_Error("Setting console mode failed", ::GetLastError());
}
void reenable_echo() override {
if(m_input_handle != INVALID_HANDLE_VALUE) {
if(::SetConsoleMode(m_input_handle, m_console_state) == 0)
throw System_Error("Setting console mode failed", ::GetLastError());
m_input_handle = INVALID_HANDLE_VALUE;
}
}
~Win32_Echo_Suppression() override {
try {
reenable_echo();
} catch(...) {}
}
Win32_Echo_Suppression(const Win32_Echo_Suppression& other) = delete;
Win32_Echo_Suppression(Win32_Echo_Suppression&& other) = delete;
Win32_Echo_Suppression& operator=(const Win32_Echo_Suppression& other) = delete;
Win32_Echo_Suppression& operator=(Win32_Echo_Suppression&& other) = delete;
private:
HANDLE m_input_handle;
DWORD m_console_state;
};
return std::make_unique<Win32_Echo_Suppression>();
#else
// Not supported on this platform, return null
return nullptr;
#endif
}
} // namespace Botan