Line data    Source code

       1             : // Copyright (c) 2009-2010 Satoshi Nakamoto
       2             : // Copyright (c) 2009-2021 The Bitcoin Core developers
       3             : // Distributed under the MIT software license, see the accompanying
       4             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       5             : 
       6             : #if defined(HAVE_CONFIG_H)
       7             : #include <config/bitcoin-config.h>
       8             : #endif
       9             : 
      10             : #include <randomenv.h>
      11             : 
      12             : #include <clientversion.h>
      13             : #include <compat/cpuid.h>
      14             : #include <crypto/sha512.h>
      15             : #include <span.h>
      16             : #include <support/cleanse.h>
      17             : #include <util/time.h>
      18             : 
      19             : #include <algorithm>
      20             : #include <atomic>
      21             : #include <cstdint>
      22             : #include <cstring>
      23             : #include <chrono>
      24             : #include <climits>
      25             : #include <thread>
      26             : #include <vector>
      27             : 
      28             : #include <sys/types.h> // must go before a number of other headers
      29             : 
      30             : #ifdef WIN32
      31             : #include <windows.h>
      32             : #include <winreg.h>
      33             : #else
      34             : #include <fcntl.h>
      35             : #include <netinet/in.h>
      36             : #include <sys/resource.h>
      37             : #include <sys/socket.h>
      38             : #include <sys/stat.h>
      39             : #include <sys/time.h>
      40             : #include <sys/utsname.h>
      41             : #include <unistd.h>
      42             : #endif
      43             : #if HAVE_DECL_GETIFADDRS && HAVE_DECL_FREEIFADDRS
      44             : #include <ifaddrs.h>
      45             : #endif
      46             : #if HAVE_SYSCTL
      47             : #include <sys/sysctl.h>
      48             : #if HAVE_VM_VM_PARAM_H
      49             : #include <vm/vm_param.h>
      50             : #endif
      51             : #if HAVE_SYS_RESOURCES_H
      52             : #include <sys/resources.h>
      53             : #endif
      54             : #if HAVE_SYS_VMMETER_H
      55             : #include <sys/vmmeter.h>
      56             : #endif
      57             : #endif
      58             : #if defined(HAVE_STRONG_GETAUXVAL)
      59             : #include <sys/auxv.h>
      60             : #endif
      61             : 
      62             : #ifndef _MSC_VER
      63             : //! Necessary on some platforms
      64             : extern char** environ; // NOLINT(readability-redundant-declaration): Necessary on some platforms
      65             : #endif
      66             : 
      67             : namespace {
      68             : 
      69         163 : void RandAddSeedPerfmon(CSHA512& hasher)
      70             : {
      71             : #ifdef WIN32
      72             :     // Seed with the entire set of perfmon data
      73             : 
      74             :     // This can take up to 2 seconds, so only do it every 10 minutes.
      75             :     // Initialize last_perfmon to 0 seconds, we don't skip the first call.
      76             :     static std::atomic<SteadyClock::time_point> last_perfmon{SteadyClock::time_point{0s}};
      77             :     auto last_time = last_perfmon.load();
      78             :     auto current_time = SteadyClock::now();
      79             :     if (current_time < last_time + 10min) return;
      80             :     last_perfmon = current_time;
      81             : 
      82             :     std::vector<unsigned char> vData(250000, 0);
      83             :     long ret = 0;
      84             :     unsigned long nSize = 0;
      85             :     const size_t nMaxSize = 10000000; // Bail out at more than 10MB of performance data
      86             :     while (true) {
      87             :         nSize = vData.size();
      88             :         ret = RegQueryValueExA(HKEY_PERFORMANCE_DATA, "Global", nullptr, nullptr, vData.data(), &nSize);
      89             :         if (ret != ERROR_MORE_DATA || vData.size() >= nMaxSize)
      90             :             break;
      91             :         vData.resize(std::min((vData.size() * 3) / 2, nMaxSize)); // Grow size of buffer exponentially
      92             :     }
      93             :     RegCloseKey(HKEY_PERFORMANCE_DATA);
      94             :     if (ret == ERROR_SUCCESS) {
      95             :         hasher.Write(vData.data(), nSize);
      96             :         memory_cleanse(vData.data(), nSize);
      97             :     } else {
      98             :         // Performance data is only a best-effort attempt at improving the
      99             :         // situation when the OS randomness (and other sources) aren't
     100             :         // adequate. As a result, failure to read it is isn't considered critical,
     101             :         // so we don't call RandFailure().
     102             :         // TODO: Add logging when the logger is made functional before global
     103             :         // constructors have been invoked.
     104             :     }
     105             : #endif
     106         163 : }
     107             : 
     108             : /** Helper to easily feed data into a CSHA512.
     109             :  *
     110             :  * Note that this does not serialize the passed object (like stream.h's << operators do).
     111             :  * Its raw memory representation is used directly.
     112             :  */
     113             : template<typename T>
     114       12388 : CSHA512& operator<<(CSHA512& hasher, const T& data) {
     115             :     static_assert(!std::is_same<typename std::decay<T>::type, char*>::value, "Calling operator<<(CSHA512, char*) is probably not what you want");
     116             :     static_assert(!std::is_same<typename std::decay<T>::type, unsigned char*>::value, "Calling operator<<(CSHA512, unsigned char*) is probably not what you want");
     117             :     static_assert(!std::is_same<typename std::decay<T>::type, const char*>::value, "Calling operator<<(CSHA512, const char*) is probably not what you want");
     118             :     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");
     119       12388 :     hasher.Write((const unsigned char*)&data, sizeof(data));
     120       12388 :     return hasher;
     121             : }
     122             : 
     123             : #ifndef WIN32
     124       20049 : void AddSockaddr(CSHA512& hasher, const struct sockaddr *addr)
     125             : {
     126       20049 :     if (addr == nullptr) return;
     127       10921 :     switch (addr->sa_family) {
     128             :     case AF_INET:
     129        1467 :         hasher.Write((const unsigned char*)addr, sizeof(sockaddr_in));
     130        1467 :         break;
     131             :     case AF_INET6:
     132        4075 :         hasher.Write((const unsigned char*)addr, sizeof(sockaddr_in6));
     133        4075 :         break;
     134             :     default:
     135        5379 :         hasher.Write((const unsigned char*)&addr->sa_family, sizeof(addr->sa_family));
     136        5379 :     }
     137       20049 : }
     138             : 
     139         978 : void AddFile(CSHA512& hasher, const char *path)
     140             : {
     141         978 :     struct stat sb = {};
     142         978 :     int f = open(path, O_RDONLY);
     143         978 :     size_t total = 0;
     144         978 :     if (f != -1) {
     145             :         unsigned char fbuf[4096];
     146             :         int n;
     147         815 :         hasher.Write((const unsigned char*)&f, sizeof(f));
     148         815 :         if (fstat(f, &sb) == 0) hasher << sb;
     149         815 :         do {
     150        1141 :             n = read(f, fbuf, sizeof(fbuf));
     151        1141 :             if (n > 0) hasher.Write(fbuf, n);
     152        1141 :             total += n;
     153             :             /* not bothering with EINTR handling. */
     154        1141 :         } while (n == sizeof(fbuf) && total < 1048576); // Read only the first 1 Mbyte
     155         815 :         close(f);
     156         815 :     }
     157         978 : }
     158             : 
     159         815 : void AddPath(CSHA512& hasher, const char *path)
     160             : {
     161         815 :     struct stat sb = {};
     162         815 :     if (stat(path, &sb) == 0) {
     163         652 :         hasher.Write((const unsigned char*)path, strlen(path) + 1);
     164         652 :         hasher << sb;
     165         652 :     }
     166         815 : }
     167             : #endif
     168             : 
     169             : #if HAVE_SYSCTL
     170             : template<int... S>
     171        3912 : void AddSysctl(CSHA512& hasher)
     172             : {
     173        3912 :     int CTL[sizeof...(S)] = {S...};
     174             :     unsigned char buffer[65536];
     175        3912 :     size_t siz = 65536;
     176        3912 :     int ret = sysctl(CTL, sizeof...(S), buffer, &siz, nullptr, 0);
     177        3912 :     if (ret == 0 || (ret == -1 && errno == ENOMEM)) {
     178        2771 :         hasher << sizeof(CTL);
     179        2771 :         hasher.Write((const unsigned char*)CTL, sizeof(CTL));
     180        2771 :         if (siz > sizeof(buffer)) siz = sizeof(buffer);
     181        2771 :         hasher << siz;
     182        2771 :         hasher.Write(buffer, siz);
     183        2771 :     }
     184        3912 : }
     185             : #endif
     186             : 
     187             : #ifdef HAVE_GETCPUID
     188             : void inline AddCPUID(CSHA512& hasher, uint32_t leaf, uint32_t subleaf, uint32_t& ax, uint32_t& bx, uint32_t& cx, uint32_t& dx)
     189             : {
     190             :     GetCPUID(leaf, subleaf, ax, bx, cx, dx);
     191             :     hasher << leaf << subleaf << ax << bx << cx << dx;
     192             : }
     193             : 
     194             : void AddAllCPUID(CSHA512& hasher)
     195             : {
     196             :     uint32_t ax, bx, cx, dx;
     197             :     // Iterate over all standard leaves
     198             :     AddCPUID(hasher, 0, 0, ax, bx, cx, dx); // Returns max leaf in ax
     199             :     uint32_t max = ax;
     200             :     for (uint32_t leaf = 1; leaf <= max && leaf <= 0xFF; ++leaf) {
     201             :         uint32_t maxsub = 0;
     202             :         for (uint32_t subleaf = 0; subleaf <= 0xFF; ++subleaf) {
     203             :             AddCPUID(hasher, leaf, subleaf, ax, bx, cx, dx);
     204             :             // Iterate subleafs for leaf values 4, 7, 11, 13
     205             :             if (leaf == 4) {
     206             :                 if ((ax & 0x1f) == 0) break;
     207             :             } else if (leaf == 7) {
     208             :                 if (subleaf == 0) maxsub = ax;
     209             :                 if (subleaf == maxsub) break;
     210             :             } else if (leaf == 11) {
     211             :                 if ((cx & 0xff00) == 0) break;
     212             :             } else if (leaf == 13) {
     213             :                 if (ax == 0 && bx == 0 && cx == 0 && dx == 0) break;
     214             :             } else {
     215             :                 // For any other leaf, stop after subleaf 0.
     216             :                 break;
     217             :             }
     218             :         }
     219             :     }
     220             :     // Iterate over all extended leaves
     221             :     AddCPUID(hasher, 0x80000000, 0, ax, bx, cx, dx); // Returns max extended leaf in ax
     222             :     uint32_t ext_max = ax;
     223             :     for (uint32_t leaf = 0x80000001; leaf <= ext_max && leaf <= 0x800000FF; ++leaf) {
     224             :         AddCPUID(hasher, leaf, 0, ax, bx, cx, dx);
     225             :     }
     226             : }
     227             : #endif
     228             : } // namespace
     229             : 
     230         163 : void RandAddDynamicEnv(CSHA512& hasher)
     231             : {
     232         163 :     RandAddSeedPerfmon(hasher);
     233             : 
     234             :     // Various clocks
     235             : #ifdef WIN32
     236             :     FILETIME ftime;
     237             :     GetSystemTimeAsFileTime(&ftime);
     238             :     hasher << ftime;
     239             : #else
     240         163 :     struct timespec ts = {};
     241             : #    ifdef CLOCK_MONOTONIC
     242         163 :     clock_gettime(CLOCK_MONOTONIC, &ts);
     243         163 :     hasher << ts;
     244             : #    endif
     245             : #    ifdef CLOCK_REALTIME
     246         163 :     clock_gettime(CLOCK_REALTIME, &ts);
     247         163 :     hasher << ts;
     248             : #    endif
     249             : #    ifdef CLOCK_BOOTTIME
     250             :     clock_gettime(CLOCK_BOOTTIME, &ts);
     251             :     hasher << ts;
     252             : #    endif
     253             :     // gettimeofday is available on all UNIX systems, but only has microsecond precision.
     254         163 :     struct timeval tv = {};
     255         163 :     gettimeofday(&tv, nullptr);
     256         163 :     hasher << tv;
     257             : #endif
     258             :     // Probably redundant, but also use all the standard library clocks:
     259         163 :     hasher << std::chrono::system_clock::now().time_since_epoch().count();
     260         163 :     hasher << std::chrono::steady_clock::now().time_since_epoch().count();
     261         163 :     hasher << std::chrono::high_resolution_clock::now().time_since_epoch().count();
     262             : 
     263             : #ifndef WIN32
     264             :     // Current resource usage.
     265         163 :     struct rusage usage = {};
     266         163 :     if (getrusage(RUSAGE_SELF, &usage) == 0) hasher << usage;
     267             : #endif
     268             : 
     269             : #ifdef __linux__
     270             :     AddFile(hasher, "/proc/diskstats");
     271             :     AddFile(hasher, "/proc/vmstat");
     272             :     AddFile(hasher, "/proc/schedstat");
     273             :     AddFile(hasher, "/proc/zoneinfo");
     274             :     AddFile(hasher, "/proc/meminfo");
     275             :     AddFile(hasher, "/proc/softirqs");
     276             :     AddFile(hasher, "/proc/stat");
     277             :     AddFile(hasher, "/proc/self/schedstat");
     278             :     AddFile(hasher, "/proc/self/status");
     279             : #endif
     280             : 
     281             : #if HAVE_SYSCTL
     282             : #  ifdef CTL_KERN
     283             : #    if defined(KERN_PROC) && defined(KERN_PROC_ALL)
     284         163 :     AddSysctl<CTL_KERN, KERN_PROC, KERN_PROC_ALL>(hasher);
     285             : #    endif
     286             : #  endif
     287             : #  ifdef CTL_HW
     288             : #    ifdef HW_DISKSTATS
     289         163 :     AddSysctl<CTL_HW, HW_DISKSTATS>(hasher);
     290             : #    endif
     291             : #  endif
     292             : #  ifdef CTL_VM
     293             : #    ifdef VM_LOADAVG
     294         163 :     AddSysctl<CTL_VM, VM_LOADAVG>(hasher);
     295             : #    endif
     296             : #    ifdef VM_TOTAL
     297             :     AddSysctl<CTL_VM, VM_TOTAL>(hasher);
     298             : #    endif
     299             : #    ifdef VM_METER
     300         163 :     AddSysctl<CTL_VM, VM_METER>(hasher);
     301             : #    endif
     302             : #  endif
     303             : #endif
     304             : 
     305             :     // Stack and heap location
     306         163 :     void* addr = malloc(4097);
     307         163 :     hasher << &addr << addr;
     308         163 :     free(addr);
     309         163 : }
     310             : 
     311         163 : void RandAddStaticEnv(CSHA512& hasher)
     312             : {
     313             :     // Some compile-time static properties
     314         163 :     hasher << (CHAR_MIN < 0) << sizeof(void*) << sizeof(long) << sizeof(int);
     315             : #if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__)
     316         163 :     hasher << __GNUC__ << __GNUC_MINOR__ << __GNUC_PATCHLEVEL__;
     317             : #endif
     318             : #ifdef _MSC_VER
     319             :     hasher << _MSC_VER;
     320             : #endif
     321         163 :     hasher << __cplusplus;
     322             : #ifdef _XOPEN_VERSION
     323         163 :     hasher << _XOPEN_VERSION;
     324             : #endif
     325             : #ifdef __VERSION__
     326         163 :     const char* COMPILER_VERSION = __VERSION__;
     327         163 :     hasher.Write((const unsigned char*)COMPILER_VERSION, strlen(COMPILER_VERSION) + 1);
     328             : #endif
     329             : 
     330             :     // Bitcoin client version
     331         163 :     hasher << CLIENT_VERSION;
     332             : 
     333             : #if defined(HAVE_STRONG_GETAUXVAL)
     334             :     // Information available through getauxval()
     335             : #  ifdef AT_HWCAP
     336             :     hasher << getauxval(AT_HWCAP);
     337             : #  endif
     338             : #  ifdef AT_HWCAP2
     339             :     hasher << getauxval(AT_HWCAP2);
     340             : #  endif
     341             : #  ifdef AT_RANDOM
     342             :     const unsigned char* random_aux = (const unsigned char*)getauxval(AT_RANDOM);
     343             :     if (random_aux) hasher.Write(random_aux, 16);
     344             : #  endif
     345             : #  ifdef AT_PLATFORM
     346             :     const char* platform_str = (const char*)getauxval(AT_PLATFORM);
     347             :     if (platform_str) hasher.Write((const unsigned char*)platform_str, strlen(platform_str) + 1);
     348             : #  endif
     349             : #  ifdef AT_EXECFN
     350             :     const char* exec_str = (const char*)getauxval(AT_EXECFN);
     351             :     if (exec_str) hasher.Write((const unsigned char*)exec_str, strlen(exec_str) + 1);
     352             : #  endif
     353             : #endif // HAVE_STRONG_GETAUXVAL
     354             : 
     355             : #ifdef HAVE_GETCPUID
     356             :     AddAllCPUID(hasher);
     357             : #endif
     358             : 
     359             :     // Memory locations
     360         163 :     hasher << &hasher << &RandAddStaticEnv << &malloc << &errno << &environ;
     361             : 
     362             :     // Hostname
     363             : #ifdef WIN32
     364             :     constexpr DWORD max_size = MAX_COMPUTERNAME_LENGTH + 1;
     365             :     char hname[max_size];
     366             :     DWORD size = max_size;
     367             :     if (GetComputerNameA(hname, &size) != 0) {
     368             :         hasher.Write(UCharCast(hname), size);
     369             :     }
     370             : #else
     371             :     char hname[256];
     372         163 :     if (gethostname(hname, 256) == 0) {
     373         163 :         hasher.Write((const unsigned char*)hname, strnlen(hname, 256));
     374         163 :     }
     375             : #endif
     376             : 
     377             : #if HAVE_DECL_GETIFADDRS && HAVE_DECL_FREEIFADDRS
     378             :     // Network interfaces
     379         163 :     struct ifaddrs *ifad = nullptr;
     380         163 :     getifaddrs(&ifad);
     381         163 :     struct ifaddrs *ifit = ifad;
     382        6846 :     while (ifit != nullptr) {
     383        6683 :         hasher.Write((const unsigned char*)&ifit, sizeof(ifit));
     384        6683 :         hasher.Write((const unsigned char*)ifit->ifa_name, strlen(ifit->ifa_name) + 1);
     385        6683 :         hasher.Write((const unsigned char*)&ifit->ifa_flags, sizeof(ifit->ifa_flags));
     386        6683 :         AddSockaddr(hasher, ifit->ifa_addr);
     387        6683 :         AddSockaddr(hasher, ifit->ifa_netmask);
     388        6683 :         AddSockaddr(hasher, ifit->ifa_dstaddr);
     389        6683 :         ifit = ifit->ifa_next;
     390             :     }
     391         163 :     freeifaddrs(ifad);
     392             : #endif
     393             : 
     394             : #ifndef WIN32
     395             :     // UNIX kernel information
     396             :     struct utsname name;
     397         163 :     if (uname(&name) != -1) {
     398         163 :         hasher.Write((const unsigned char*)&name.sysname, strlen(name.sysname) + 1);
     399         163 :         hasher.Write((const unsigned char*)&name.nodename, strlen(name.nodename) + 1);
     400         163 :         hasher.Write((const unsigned char*)&name.release, strlen(name.release) + 1);
     401         163 :         hasher.Write((const unsigned char*)&name.version, strlen(name.version) + 1);
     402         163 :         hasher.Write((const unsigned char*)&name.machine, strlen(name.machine) + 1);
     403         163 :     }
     404             : 
     405             :     /* Path and filesystem provided data */
     406         163 :     AddPath(hasher, "/");
     407         163 :     AddPath(hasher, ".");
     408         163 :     AddPath(hasher, "/tmp");
     409         163 :     AddPath(hasher, "/home");
     410         163 :     AddPath(hasher, "/proc");
     411             : #ifdef __linux__
     412             :     AddFile(hasher, "/proc/cmdline");
     413             :     AddFile(hasher, "/proc/cpuinfo");
     414             :     AddFile(hasher, "/proc/version");
     415             : #endif
     416         163 :     AddFile(hasher, "/etc/passwd");
     417         163 :     AddFile(hasher, "/etc/group");
     418         163 :     AddFile(hasher, "/etc/hosts");
     419         163 :     AddFile(hasher, "/etc/resolv.conf");
     420         163 :     AddFile(hasher, "/etc/timezone");
     421         163 :     AddFile(hasher, "/etc/localtime");
     422             : #endif
     423             : 
     424             :     // For MacOS/BSDs, gather data through sysctl instead of /proc. Not all of these
     425             :     // will exist on every system.
     426             : #if HAVE_SYSCTL
     427             : #  ifdef CTL_HW
     428             : #    ifdef HW_MACHINE
     429         163 :     AddSysctl<CTL_HW, HW_MACHINE>(hasher);
     430             : #    endif
     431             : #    ifdef HW_MODEL
     432         163 :     AddSysctl<CTL_HW, HW_MODEL>(hasher);
     433             : #    endif
     434             : #    ifdef HW_NCPU
     435         163 :     AddSysctl<CTL_HW, HW_NCPU>(hasher);
     436             : #    endif
     437             : #    ifdef HW_PHYSMEM
     438         163 :     AddSysctl<CTL_HW, HW_PHYSMEM>(hasher);
     439             : #    endif
     440             : #    ifdef HW_USERMEM
     441         163 :     AddSysctl<CTL_HW, HW_USERMEM>(hasher);
     442             : #    endif
     443             : #    ifdef HW_MACHINE_ARCH
     444         163 :     AddSysctl<CTL_HW, HW_MACHINE_ARCH>(hasher);
     445             : #    endif
     446             : #    ifdef HW_REALMEM
     447             :     AddSysctl<CTL_HW, HW_REALMEM>(hasher);
     448             : #    endif
     449             : #    ifdef HW_CPU_FREQ
     450         163 :     AddSysctl<CTL_HW, HW_CPU_FREQ>(hasher);
     451             : #    endif
     452             : #    ifdef HW_BUS_FREQ
     453         163 :     AddSysctl<CTL_HW, HW_BUS_FREQ>(hasher);
     454             : #    endif
     455             : #    ifdef HW_CACHELINE
     456         163 :     AddSysctl<CTL_HW, HW_CACHELINE>(hasher);
     457             : #    endif
     458             : #  endif
     459             : #  ifdef CTL_KERN
     460             : #    ifdef KERN_BOOTFILE
     461         163 :      AddSysctl<CTL_KERN, KERN_BOOTFILE>(hasher);
     462             : #    endif
     463             : #    ifdef KERN_BOOTTIME
     464         163 :      AddSysctl<CTL_KERN, KERN_BOOTTIME>(hasher);
     465             : #    endif
     466             : #    ifdef KERN_CLOCKRATE
     467         163 :      AddSysctl<CTL_KERN, KERN_CLOCKRATE>(hasher);
     468             : #    endif
     469             : #    ifdef KERN_HOSTID
     470         163 :      AddSysctl<CTL_KERN, KERN_HOSTID>(hasher);
     471             : #    endif
     472             : #    ifdef KERN_HOSTUUID
     473             :      AddSysctl<CTL_KERN, KERN_HOSTUUID>(hasher);
     474             : #    endif
     475             : #    ifdef KERN_HOSTNAME
     476         163 :      AddSysctl<CTL_KERN, KERN_HOSTNAME>(hasher);
     477             : #    endif
     478             : #    ifdef KERN_OSRELDATE
     479         163 :      AddSysctl<CTL_KERN, KERN_OSRELDATE>(hasher);
     480             : #    endif
     481             : #    ifdef KERN_OSRELEASE
     482         163 :      AddSysctl<CTL_KERN, KERN_OSRELEASE>(hasher);
     483             : #    endif
     484             : #    ifdef KERN_OSREV
     485         163 :      AddSysctl<CTL_KERN, KERN_OSREV>(hasher);
     486             : #    endif
     487             : #    ifdef KERN_OSTYPE
     488         163 :      AddSysctl<CTL_KERN, KERN_OSTYPE>(hasher);
     489             : #    endif
     490             : #    ifdef KERN_POSIX1
     491         163 :      AddSysctl<CTL_KERN, KERN_OSREV>(hasher);
     492             : #    endif
     493             : #    ifdef KERN_VERSION
     494         163 :      AddSysctl<CTL_KERN, KERN_VERSION>(hasher);
     495             : #    endif
     496             : #  endif
     497             : #endif
     498             : 
     499             :     // Env variables
     500         163 :     if (environ) {
     501        4238 :         for (size_t i = 0; environ[i]; ++i) {
     502        4075 :             hasher.Write((const unsigned char*)environ[i], strlen(environ[i]));
     503        4075 :         }
     504         163 :     }
     505             : 
     506             :     // Process, thread, user, session, group, ... ids.
     507             : #ifdef WIN32
     508             :     hasher << GetCurrentProcessId() << GetCurrentThreadId();
     509             : #else
     510         163 :     hasher << getpid() << getppid() << getsid(0) << getpgid(0) << getuid() << geteuid() << getgid() << getegid();
     511             : #endif
     512         163 :     hasher << std::this_thread::get_id();
     513         163 : }