bitcoin/src/randomenv.cpp
fanquake 4fcfcc294e
random: stop retrieving random bytes from OpenSSL
On the ::SLOW path we would use OpenSSL as an additional source of
random bytes. This commit removes that functionality. Note that this was
always only an additional source, and that we never checked the return
value

RAND_bytes(): https://www.openssl.org/docs/manmaster/man3/RAND_bytes.html

RAND_bytes() puts num cryptographically strong pseudo-random bytes into buf.
2019-11-18 08:56:40 -05:00

507 lines
15 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2019 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#if defined(HAVE_CONFIG_H)
#include <config/bitcoin-config.h>
#endif
#include <randomenv.h>
#include <clientversion.h>
#include <compat/cpuid.h>
#include <crypto/sha512.h>
#include <support/cleanse.h>
#include <util/time.h> // for GetTime()
#ifdef WIN32
#include <compat.h> // for Windows API
#endif
#include <algorithm>
#include <atomic>
#include <chrono>
#include <climits>
#include <thread>
#include <vector>
#include <stdint.h>
#include <string.h>
#ifndef WIN32
#include <sys/types.h> // must go before a number of other headers
#include <fcntl.h>
#include <netinet/in.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/utsname.h>
#include <unistd.h>
#endif
#ifdef __MACH__
#include <mach/clock.h>
#include <mach/mach.h>
#include <mach/mach_time.h>
#endif
#if HAVE_DECL_GETIFADDRS
#include <ifaddrs.h>
#endif
#if HAVE_SYSCTL
#include <sys/sysctl.h>
#if HAVE_VM_VM_PARAM_H
#include <vm/vm_param.h>
#endif
#if HAVE_SYS_RESOURCES_H
#include <sys/resources.h>
#endif
#if HAVE_SYS_VMMETER_H
#include <sys/vmmeter.h>
#endif
#endif
#ifdef __linux__
#include <sys/auxv.h>
#endif
//! Necessary on some platforms
extern char** environ;
namespace {
void RandAddSeedPerfmon(CSHA512& hasher)
{
#ifdef WIN32
// Seed with the entire set of perfmon data
// This can take up to 2 seconds, so only do it every 10 minutes
static std::atomic<std::chrono::seconds> last_perfmon{std::chrono::seconds{0}};
auto last_time = last_perfmon.load();
auto current_time = GetTime<std::chrono::seconds>();
if (current_time < last_time + std::chrono::minutes{10}) return;
last_perfmon = current_time;
std::vector<unsigned char> vData(250000, 0);
long ret = 0;
unsigned long nSize = 0;
const size_t nMaxSize = 10000000; // Bail out at more than 10MB of performance data
while (true) {
nSize = vData.size();
ret = RegQueryValueExA(HKEY_PERFORMANCE_DATA, "Global", nullptr, nullptr, vData.data(), &nSize);
if (ret != ERROR_MORE_DATA || vData.size() >= nMaxSize)
break;
vData.resize(std::max((vData.size() * 3) / 2, nMaxSize)); // Grow size of buffer exponentially
}
RegCloseKey(HKEY_PERFORMANCE_DATA);
if (ret == ERROR_SUCCESS) {
hasher.Write(vData.data(), nSize);
memory_cleanse(vData.data(), nSize);
} else {
// Performance data is only a best-effort attempt at improving the
// situation when the OS randomness (and other sources) aren't
// adequate. As a result, failure to read it is isn't considered critical,
// so we don't call RandFailure().
// TODO: Add logging when the logger is made functional before global
// constructors have been invoked.
}
#endif
}
/** Helper to easily feed data into a CSHA512.
*
* Note that this does not serialize the passed object (like stream.h's << operators do).
* Its raw memory representation is used directly.
*/
template<typename T>
CSHA512& operator<<(CSHA512& hasher, const T& data) {
static_assert(!std::is_same<typename std::decay<T>::type, char*>::value, "Calling operator<<(CSHA512, char*) is probably not what you want");
static_assert(!std::is_same<typename std::decay<T>::type, unsigned char*>::value, "Calling operator<<(CSHA512, unsigned char*) is probably not what you want");
static_assert(!std::is_same<typename std::decay<T>::type, const char*>::value, "Calling operator<<(CSHA512, const char*) is probably not what you want");
static_assert(!std::is_same<typename std::decay<T>::type, const unsigned char*>::value, "Calling operator<<(CSHA512, const unsigned char*) is probably not what you want");
hasher.Write((const unsigned char*)&data, sizeof(data));
return hasher;
}
#ifndef WIN32
void AddSockaddr(CSHA512& hasher, const struct sockaddr *addr)
{
if (addr == nullptr) return;
switch (addr->sa_family) {
case AF_INET:
hasher.Write((const unsigned char*)addr, sizeof(sockaddr_in));
break;
case AF_INET6:
hasher.Write((const unsigned char*)addr, sizeof(sockaddr_in6));
break;
default:
hasher.Write((const unsigned char*)&addr->sa_family, sizeof(addr->sa_family));
}
}
void AddFile(CSHA512& hasher, const char *path)
{
struct stat sb = {};
int f = open(path, O_RDONLY);
size_t total = 0;
if (f != -1) {
unsigned char fbuf[4096];
int n;
hasher.Write((const unsigned char*)&f, sizeof(f));
if (fstat(f, &sb) == 0) hasher << sb;
do {
n = read(f, fbuf, sizeof(fbuf));
if (n > 0) hasher.Write(fbuf, n);
total += n;
/* not bothering with EINTR handling. */
} while (n == sizeof(fbuf) && total < 1048576); // Read only the first 1 Mbyte
close(f);
}
}
void AddPath(CSHA512& hasher, const char *path)
{
struct stat sb = {};
if (stat(path, &sb) == 0) {
hasher.Write((const unsigned char*)path, strlen(path) + 1);
hasher << sb;
}
}
#endif
#if HAVE_SYSCTL
template<int... S>
void AddSysctl(CSHA512& hasher)
{
int CTL[sizeof...(S)] = {S...};
unsigned char buffer[65536];
size_t siz = 65536;
int ret = sysctl(CTL, sizeof...(S), buffer, &siz, nullptr, 0);
if (ret == 0 || (ret == -1 && errno == ENOMEM)) {
hasher << sizeof(CTL);
hasher.Write((const unsigned char*)CTL, sizeof(CTL));
if (siz > sizeof(buffer)) siz = sizeof(buffer);
hasher << siz;
hasher.Write(buffer, siz);
}
}
#endif
#ifdef HAVE_GETCPUID
void inline AddCPUID(CSHA512& hasher, uint32_t leaf, uint32_t subleaf, uint32_t& ax, uint32_t& bx, uint32_t& cx, uint32_t& dx)
{
GetCPUID(leaf, subleaf, ax, bx, cx, dx);
hasher << leaf << subleaf << ax << bx << cx << dx;
}
void AddAllCPUID(CSHA512& hasher)
{
uint32_t ax, bx, cx, dx;
// Iterate over all standard leaves
AddCPUID(hasher, 0, 0, ax, bx, cx, dx); // Returns max leaf in ax
uint32_t max = ax;
for (uint32_t leaf = 1; leaf <= max; ++leaf) {
for (uint32_t subleaf = 0;; ++subleaf) {
AddCPUID(hasher, leaf, subleaf, ax, bx, cx, dx);
// Iterate over subleaves for leaf 4, 11, 13
if (leaf != 4 && leaf != 11 && leaf != 13) break;
if ((leaf == 4 || leaf == 13) && ax == 0) break;
if (leaf == 11 && (cx & 0xFF00) == 0) break;
}
}
// Iterate over all extended leaves
AddCPUID(hasher, 0x80000000, 0, ax, bx, cx, dx); // Returns max extended leaf in ax
uint32_t ext_max = ax;
for (uint32_t leaf = 0x80000001; leaf <= ext_max; ++leaf) {
AddCPUID(hasher, leaf, 0, ax, bx, cx, dx);
}
}
#endif
} // namespace
void RandAddDynamicEnv(CSHA512& hasher)
{
RandAddSeedPerfmon(hasher);
// Various clocks
#ifdef WIN32
FILETIME ftime;
GetSystemTimeAsFileTime(&ftime);
hasher << ftime;
#else
# ifndef __MACH__
// On non-MacOS systems, use various clock_gettime() calls.
struct timespec ts = {};
# ifdef CLOCK_MONOTONIC
clock_gettime(CLOCK_MONOTONIC, &ts);
hasher << ts;
# endif
# ifdef CLOCK_REALTIME
clock_gettime(CLOCK_REALTIME, &ts);
hasher << ts;
# endif
# ifdef CLOCK_BOOTTIME
clock_gettime(CLOCK_BOOTTIME, &ts);
hasher << ts;
# endif
# else
// On MacOS use mach_absolute_time (number of CPU ticks since boot) as a replacement for CLOCK_MONOTONIC,
// and clock_get_time for CALENDAR_CLOCK as a replacement for CLOCK_REALTIME.
hasher << mach_absolute_time();
// From https://gist.github.com/jbenet/1087739
clock_serv_t cclock;
mach_timespec_t mts = {};
if (host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock) == KERN_SUCCESS && clock_get_time(cclock, &mts) == KERN_SUCCESS) {
hasher << mts;
mach_port_deallocate(mach_task_self(), cclock);
}
# endif
// gettimeofday is available on all UNIX systems, but only has microsecond precision.
struct timeval tv = {};
gettimeofday(&tv, nullptr);
hasher << tv;
#endif
// Probably redundant, but also use all the clocks C++11 provides:
hasher << std::chrono::system_clock::now().time_since_epoch().count();
hasher << std::chrono::steady_clock::now().time_since_epoch().count();
hasher << std::chrono::high_resolution_clock::now().time_since_epoch().count();
#ifndef WIN32
// Current resource usage.
struct rusage usage = {};
if (getrusage(RUSAGE_SELF, &usage) == 0) hasher << usage;
#endif
#ifdef __linux__
AddFile(hasher, "/proc/diskstats");
AddFile(hasher, "/proc/vmstat");
AddFile(hasher, "/proc/schedstat");
AddFile(hasher, "/proc/zoneinfo");
AddFile(hasher, "/proc/meminfo");
AddFile(hasher, "/proc/softirqs");
AddFile(hasher, "/proc/stat");
AddFile(hasher, "/proc/self/schedstat");
AddFile(hasher, "/proc/self/status");
#endif
#if HAVE_SYSCTL
# ifdef CTL_KERN
# if defined(KERN_PROC) && defined(KERN_PROC_ALL)
AddSysctl<CTL_KERN, KERN_PROC, KERN_PROC_ALL>(hasher);
# endif
# endif
# ifdef CTL_HW
# ifdef HW_DISKSTATS
AddSysctl<CTL_HW, HW_DISKSTATS>(hasher);
# endif
# endif
# ifdef CTL_VM
# ifdef VM_LOADAVG
AddSysctl<CTL_VM, VM_LOADAVG>(hasher);
# endif
# ifdef VM_TOTAL
AddSysctl<CTL_VM, VM_TOTAL>(hasher);
# endif
# ifdef VM_METER
AddSysctl<CTL_VM, VM_METER>(hasher);
# endif
# endif
#endif
// Stack and heap location
void* addr = malloc(4097);
hasher << &addr << addr;
free(addr);
}
void RandAddStaticEnv(CSHA512& hasher)
{
// Some compile-time static properties
hasher << (CHAR_MIN < 0) << sizeof(void*) << sizeof(long) << sizeof(int);
#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__)
hasher << __GNUC__ << __GNUC_MINOR__ << __GNUC_PATCHLEVEL__;
#endif
#ifdef _MSC_VER
hasher << _MSC_VER;
#endif
hasher << __cplusplus;
#ifdef _XOPEN_VERSION
hasher << _XOPEN_VERSION;
#endif
#ifdef __VERSION__
const char* COMPILER_VERSION = __VERSION__;
hasher.Write((const unsigned char*)COMPILER_VERSION, strlen(COMPILER_VERSION) + 1);
#endif
// Bitcoin client version
hasher << CLIENT_VERSION;
#ifdef __linux__
// Information available through getauxval()
# ifdef AT_HWCAP
hasher << getauxval(AT_HWCAP);
# endif
# ifdef AT_HWCAP2
hasher << getauxval(AT_HWCAP2);
# endif
# ifdef AT_RANDOM
const unsigned char* random_aux = (const unsigned char*)getauxval(AT_RANDOM);
if (random_aux) hasher.Write(random_aux, 16);
# endif
# ifdef AT_PLATFORM
const char* platform_str = (const char*)getauxval(AT_PLATFORM);
if (platform_str) hasher.Write((const unsigned char*)platform_str, strlen(platform_str) + 1);
# endif
# ifdef AT_EXECFN
const char* exec_str = (const char*)getauxval(AT_EXECFN);
if (exec_str) hasher.Write((const unsigned char*)exec_str, strlen(exec_str) + 1);
# endif
#endif // __linux__
#ifdef HAVE_GETCPUID
AddAllCPUID(hasher);
#endif
// Memory locations
hasher << &hasher << &RandAddStaticEnv << &malloc << &errno << &environ;
// Hostname
char hname[256];
if (gethostname(hname, 256) == 0) {
hasher.Write((const unsigned char*)hname, strnlen(hname, 256));
}
#if HAVE_DECL_GETIFADDRS
// Network interfaces
struct ifaddrs *ifad = NULL;
getifaddrs(&ifad);
struct ifaddrs *ifit = ifad;
while (ifit != NULL) {
hasher.Write((const unsigned char*)&ifit, sizeof(ifit));
hasher.Write((const unsigned char*)ifit->ifa_name, strlen(ifit->ifa_name) + 1);
hasher.Write((const unsigned char*)&ifit->ifa_flags, sizeof(ifit->ifa_flags));
AddSockaddr(hasher, ifit->ifa_addr);
AddSockaddr(hasher, ifit->ifa_netmask);
AddSockaddr(hasher, ifit->ifa_dstaddr);
ifit = ifit->ifa_next;
}
freeifaddrs(ifad);
#endif
#ifndef WIN32
// UNIX kernel information
struct utsname name;
if (uname(&name) != -1) {
hasher.Write((const unsigned char*)&name.sysname, strlen(name.sysname) + 1);
hasher.Write((const unsigned char*)&name.nodename, strlen(name.nodename) + 1);
hasher.Write((const unsigned char*)&name.release, strlen(name.release) + 1);
hasher.Write((const unsigned char*)&name.version, strlen(name.version) + 1);
hasher.Write((const unsigned char*)&name.machine, strlen(name.machine) + 1);
}
/* Path and filesystem provided data */
AddPath(hasher, "/");
AddPath(hasher, ".");
AddPath(hasher, "/tmp");
AddPath(hasher, "/home");
AddPath(hasher, "/proc");
#ifdef __linux__
AddFile(hasher, "/proc/cmdline");
AddFile(hasher, "/proc/cpuinfo");
AddFile(hasher, "/proc/version");
#endif
AddFile(hasher, "/etc/passwd");
AddFile(hasher, "/etc/group");
AddFile(hasher, "/etc/hosts");
AddFile(hasher, "/etc/resolv.conf");
AddFile(hasher, "/etc/timezone");
AddFile(hasher, "/etc/localtime");
#endif
// For MacOS/BSDs, gather data through sysctl instead of /proc. Not all of these
// will exist on every system.
#if HAVE_SYSCTL
# ifdef CTL_HW
# ifdef HW_MACHINE
AddSysctl<CTL_HW, HW_MACHINE>(hasher);
# endif
# ifdef HW_MODEL
AddSysctl<CTL_HW, HW_MODEL>(hasher);
# endif
# ifdef HW_NCPU
AddSysctl<CTL_HW, HW_NCPU>(hasher);
# endif
# ifdef HW_PHYSMEM
AddSysctl<CTL_HW, HW_PHYSMEM>(hasher);
# endif
# ifdef HW_USERMEM
AddSysctl<CTL_HW, HW_USERMEM>(hasher);
# endif
# ifdef HW_MACHINE_ARCH
AddSysctl<CTL_HW, HW_MACHINE_ARCH>(hasher);
# endif
# ifdef HW_REALMEM
AddSysctl<CTL_HW, HW_REALMEM>(hasher);
# endif
# ifdef HW_CPU_FREQ
AddSysctl<CTL_HW, HW_CPU_FREQ>(hasher);
# endif
# ifdef HW_BUS_FREQ
AddSysctl<CTL_HW, HW_BUS_FREQ>(hasher);
# endif
# ifdef HW_CACHELINE
AddSysctl<CTL_HW, HW_CACHELINE>(hasher);
# endif
# endif
# ifdef CTL_KERN
# ifdef KERN_BOOTFILE
AddSysctl<CTL_KERN, KERN_BOOTFILE>(hasher);
# endif
# ifdef KERN_BOOTTIME
AddSysctl<CTL_KERN, KERN_BOOTTIME>(hasher);
# endif
# ifdef KERN_CLOCKRATE
AddSysctl<CTL_KERN, KERN_CLOCKRATE>(hasher);
# endif
# ifdef KERN_HOSTID
AddSysctl<CTL_KERN, KERN_HOSTID>(hasher);
# endif
# ifdef KERN_HOSTUUID
AddSysctl<CTL_KERN, KERN_HOSTUUID>(hasher);
# endif
# ifdef KERN_HOSTNAME
AddSysctl<CTL_KERN, KERN_HOSTNAME>(hasher);
# endif
# ifdef KERN_OSRELDATE
AddSysctl<CTL_KERN, KERN_OSRELDATE>(hasher);
# endif
# ifdef KERN_OSRELEASE
AddSysctl<CTL_KERN, KERN_OSRELEASE>(hasher);
# endif
# ifdef KERN_OSREV
AddSysctl<CTL_KERN, KERN_OSREV>(hasher);
# endif
# ifdef KERN_OSTYPE
AddSysctl<CTL_KERN, KERN_OSTYPE>(hasher);
# endif
# ifdef KERN_POSIX1
AddSysctl<CTL_KERN, KERN_OSREV>(hasher);
# endif
# ifdef KERN_VERSION
AddSysctl<CTL_KERN, KERN_VERSION>(hasher);
# endif
# endif
#endif
// Env variables
if (environ) {
for (size_t i = 0; environ[i]; ++i) {
hasher.Write((const unsigned char*)environ[i], strlen(environ[i]));
}
}
// Process, thread, user, session, group, ... ids.
#ifdef WIN32
hasher << GetCurrentProcessId() << GetCurrentThreadId();
#else
hasher << getpid() << getppid() << getsid(0) << getpgid(0) << getuid() << geteuid() << getgid() << getegid();
#endif
hasher << std::this_thread::get_id();
}