randomenv.cpp raw
1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-present 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 #include <bitcoin-build-config.h> // IWYU pragma: keep
7
8 #include <randomenv.h>
9
10 #include <clientversion.h>
11 #include <compat/compat.h>
12 #include <compat/cpuid.h>
13 #include <crypto/sha512.h>
14 #include <span.h>
15 #include <support/cleanse.h>
16 #include <util/byte_units.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 #else
33 #include <fcntl.h>
34 #include <netinet/in.h>
35 #include <sys/resource.h>
36 #include <sys/socket.h>
37 #include <sys/stat.h>
38 #include <sys/time.h>
39 #include <sys/utsname.h>
40 #include <unistd.h>
41 #endif
42 #ifdef HAVE_IFADDRS
43 #include <ifaddrs.h>
44 #endif
45 #ifdef HAVE_SYSCTL
46 #include <sys/sysctl.h>
47 #if __has_include(<vm/vm_param.h>)
48 #include <vm/vm_param.h>
49 #endif
50 #if __has_include(<sys/resources.h>)
51 #include <sys/resources.h>
52 #endif
53 #if __has_include(<sys/vmmeter.h>)
54 #include <sys/vmmeter.h>
55 #endif
56 #endif
57 #if defined(HAVE_STRONG_GETAUXVAL)
58 #include <sys/auxv.h>
59 #endif
60
61 #if defined(__APPLE__) || \
62 defined(__FreeBSD__) || \
63 defined(__NetBSD__) || \
64 defined(__OpenBSD__) || \
65 defined(__illumos__)
66 extern char** environ; // Necessary on the above platforms
67 #endif
68
69 namespace {
70
71 /** Helper to easily feed data into a CSHA512.
72 *
73 * Note that this does not serialize the passed object (like stream.h's << operators do).
74 * Its raw memory representation is used directly.
75 */
76 template<typename T>
77 CSHA512& operator<<(CSHA512& hasher, const T& data) {
78 static_assert(!std::is_same_v<std::decay_t<T>, char*>, "Calling operator<<(CSHA512, char*) is probably not what you want");
79 static_assert(!std::is_same_v<std::decay_t<T>, unsigned char*>, "Calling operator<<(CSHA512, unsigned char*) is probably not what you want");
80 static_assert(!std::is_same_v<std::decay_t<T>, const char*>, "Calling operator<<(CSHA512, const char*) is probably not what you want");
81 static_assert(!std::is_same_v<std::decay_t<T>, const unsigned char*>, "Calling operator<<(CSHA512, const unsigned char*) is probably not what you want");
82 hasher.Write((const unsigned char*)&data, sizeof(data));
83 return hasher;
84 }
85
86 #ifndef WIN32
87 void AddSockaddr(CSHA512& hasher, const struct sockaddr *addr)
88 {
89 if (addr == nullptr) return;
90 switch (addr->sa_family) {
91 case AF_INET:
92 hasher.Write((const unsigned char*)addr, sizeof(sockaddr_in));
93 break;
94 case AF_INET6:
95 hasher.Write((const unsigned char*)addr, sizeof(sockaddr_in6));
96 break;
97 default:
98 hasher.Write((const unsigned char*)&addr->sa_family, sizeof(addr->sa_family));
99 }
100 }
101
102 void AddFile(CSHA512& hasher, const char *path)
103 {
104 struct stat sb = {};
105 int f = open(path, O_RDONLY);
106 size_t total = 0;
107 if (f != -1) {
108 unsigned char fbuf[4096];
109 int n;
110 hasher.Write((const unsigned char*)&f, sizeof(f));
111 if (fstat(f, &sb) == 0) hasher << sb;
112 do {
113 n = read(f, fbuf, sizeof(fbuf));
114 if (n > 0) hasher.Write(fbuf, n);
115 total += n;
116 /* not bothering with EINTR handling. */
117 } while (n == sizeof(fbuf) && total < 1_MiB); // Read only the first 1 Mbyte
118 close(f);
119 }
120 }
121
122 void AddPath(CSHA512& hasher, const char *path)
123 {
124 struct stat sb = {};
125 if (stat(path, &sb) == 0) {
126 hasher.Write((const unsigned char*)path, strlen(path) + 1);
127 hasher << sb;
128 }
129 }
130 #endif
131
132 #ifdef HAVE_SYSCTL
133 template<int... S>
134 void AddSysctl(CSHA512& hasher)
135 {
136 int CTL[sizeof...(S)] = {S...};
137 unsigned char buffer[65536];
138 size_t siz = 65536;
139 int ret = sysctl(CTL, sizeof...(S), buffer, &siz, nullptr, 0);
140 if (ret == 0 || (ret == -1 && errno == ENOMEM)) {
141 hasher << sizeof(CTL);
142 hasher.Write((const unsigned char*)CTL, sizeof(CTL));
143 if (siz > sizeof(buffer)) siz = sizeof(buffer);
144 hasher << siz;
145 hasher.Write(buffer, siz);
146 }
147 }
148 #endif
149
150 #ifdef HAVE_GETCPUID
151 void inline AddCPUID(CSHA512& hasher, uint32_t leaf, uint32_t subleaf, uint32_t& ax, uint32_t& bx, uint32_t& cx, uint32_t& dx)
152 {
153 GetCPUID(leaf, subleaf, ax, bx, cx, dx);
154 hasher << leaf << subleaf << ax << bx << cx << dx;
155 }
156
157 void AddAllCPUID(CSHA512& hasher)
158 {
159 uint32_t ax, bx, cx, dx;
160 // Iterate over all standard leaves
161 AddCPUID(hasher, 0, 0, ax, bx, cx, dx); // Returns max leaf in ax
162 uint32_t max = ax;
163 for (uint32_t leaf = 1; leaf <= max && leaf <= 0xFF; ++leaf) {
164 uint32_t maxsub = 0;
165 for (uint32_t subleaf = 0; subleaf <= 0xFF; ++subleaf) {
166 AddCPUID(hasher, leaf, subleaf, ax, bx, cx, dx);
167 // Iterate subleafs for leaf values 4, 7, 11, 13
168 if (leaf == 4) {
169 if ((ax & 0x1f) == 0) break;
170 } else if (leaf == 7) {
171 if (subleaf == 0) maxsub = ax;
172 if (subleaf == maxsub) break;
173 } else if (leaf == 11) {
174 if ((cx & 0xff00) == 0) break;
175 } else if (leaf == 13) {
176 if (ax == 0 && bx == 0 && cx == 0 && dx == 0) break;
177 } else {
178 // For any other leaf, stop after subleaf 0.
179 break;
180 }
181 }
182 }
183 // Iterate over all extended leaves
184 AddCPUID(hasher, 0x80000000, 0, ax, bx, cx, dx); // Returns max extended leaf in ax
185 uint32_t ext_max = ax;
186 for (uint32_t leaf = 0x80000001; leaf <= ext_max && leaf <= 0x800000FF; ++leaf) {
187 AddCPUID(hasher, leaf, 0, ax, bx, cx, dx);
188 }
189 }
190 #endif
191 } // namespace
192
193 void RandAddDynamicEnv(CSHA512& hasher)
194 {
195 // Various clocks
196 #ifdef WIN32
197 FILETIME ftime;
198 GetSystemTimeAsFileTime(&ftime);
199 hasher << ftime;
200 #else
201 struct timespec ts = {};
202 # ifdef CLOCK_MONOTONIC
203 clock_gettime(CLOCK_MONOTONIC, &ts);
204 hasher << ts;
205 # endif
206 # ifdef CLOCK_REALTIME
207 clock_gettime(CLOCK_REALTIME, &ts);
208 hasher << ts;
209 # endif
210 # ifdef CLOCK_BOOTTIME
211 clock_gettime(CLOCK_BOOTTIME, &ts);
212 hasher << ts;
213 # endif
214 // gettimeofday is available on all UNIX systems, but only has microsecond precision.
215 struct timeval tv = {};
216 gettimeofday(&tv, nullptr);
217 hasher << tv;
218 #endif
219 // Probably redundant, but also use all the standard library clocks:
220 hasher << std::chrono::system_clock::now().time_since_epoch().count();
221 hasher << std::chrono::steady_clock::now().time_since_epoch().count();
222 hasher << std::chrono::high_resolution_clock::now().time_since_epoch().count();
223
224 #ifndef WIN32
225 // Current resource usage.
226 struct rusage usage = {};
227 if (getrusage(RUSAGE_SELF, &usage) == 0) hasher << usage;
228 #endif
229
230 #ifdef __linux__
231 AddFile(hasher, "/proc/diskstats");
232 AddFile(hasher, "/proc/vmstat");
233 AddFile(hasher, "/proc/schedstat");
234 AddFile(hasher, "/proc/zoneinfo");
235 AddFile(hasher, "/proc/meminfo");
236 AddFile(hasher, "/proc/softirqs");
237 AddFile(hasher, "/proc/stat");
238 AddFile(hasher, "/proc/self/schedstat");
239 AddFile(hasher, "/proc/self/status");
240 #endif
241
242 #ifdef HAVE_SYSCTL
243 # ifdef CTL_KERN
244 # if defined(KERN_PROC) && defined(KERN_PROC_ALL)
245 AddSysctl<CTL_KERN, KERN_PROC, KERN_PROC_ALL>(hasher);
246 # endif
247 # endif
248 # ifdef CTL_HW
249 # ifdef HW_DISKSTATS
250 AddSysctl<CTL_HW, HW_DISKSTATS>(hasher);
251 # endif
252 # endif
253 # ifdef CTL_VM
254 # ifdef VM_LOADAVG
255 AddSysctl<CTL_VM, VM_LOADAVG>(hasher);
256 # endif
257 # ifdef VM_TOTAL
258 AddSysctl<CTL_VM, VM_TOTAL>(hasher);
259 # endif
260 # ifdef VM_METER
261 AddSysctl<CTL_VM, VM_METER>(hasher);
262 # endif
263 # endif
264 #endif
265
266 // Stack and heap location
267 void* addr = malloc(4097);
268 hasher << &addr << addr;
269 free(addr);
270 }
271
272 void RandAddStaticEnv(CSHA512& hasher)
273 {
274 // Some compile-time static properties
275 hasher << (CHAR_MIN < 0) << sizeof(void*) << sizeof(long) << sizeof(int);
276 #if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__)
277 hasher << __GNUC__ << __GNUC_MINOR__ << __GNUC_PATCHLEVEL__;
278 #endif
279 #ifdef _MSC_VER
280 hasher << _MSC_VER;
281 #endif
282 hasher << __cplusplus;
283 #ifdef _XOPEN_VERSION
284 hasher << _XOPEN_VERSION;
285 #endif
286 #ifdef __VERSION__
287 const char* COMPILER_VERSION = __VERSION__;
288 hasher.Write((const unsigned char*)COMPILER_VERSION, strlen(COMPILER_VERSION) + 1);
289 #endif
290
291 // Bitcoin client version
292 hasher << CLIENT_VERSION;
293
294 #if defined(HAVE_STRONG_GETAUXVAL)
295 // Information available through getauxval()
296 # ifdef AT_HWCAP
297 hasher << getauxval(AT_HWCAP);
298 # endif
299 # ifdef AT_HWCAP2
300 hasher << getauxval(AT_HWCAP2);
301 # endif
302 # ifdef AT_RANDOM
303 const unsigned char* random_aux = (const unsigned char*)getauxval(AT_RANDOM);
304 if (random_aux) hasher.Write(random_aux, 16);
305 # endif
306 # ifdef AT_PLATFORM
307 const char* platform_str = (const char*)getauxval(AT_PLATFORM);
308 if (platform_str) hasher.Write((const unsigned char*)platform_str, strlen(platform_str) + 1);
309 # endif
310 # ifdef AT_EXECFN
311 const char* exec_str = (const char*)getauxval(AT_EXECFN);
312 if (exec_str) hasher.Write((const unsigned char*)exec_str, strlen(exec_str) + 1);
313 # endif
314 #endif // HAVE_STRONG_GETAUXVAL
315
316 #ifdef HAVE_GETCPUID
317 AddAllCPUID(hasher);
318 #endif
319
320 // Memory locations
321 hasher << &hasher << &RandAddStaticEnv << &malloc << &errno << &environ;
322
323 // Hostname
324 #ifdef WIN32
325 constexpr DWORD max_size = MAX_COMPUTERNAME_LENGTH + 1;
326 char hname[max_size];
327 DWORD size = max_size;
328 if (GetComputerNameA(hname, &size) != 0) {
329 hasher.Write(UCharCast(hname), size);
330 }
331 #else
332 char hname[256];
333 if (gethostname(hname, 256) == 0) {
334 hasher.Write((const unsigned char*)hname, strnlen(hname, 256));
335 }
336 #endif
337
338 #ifdef HAVE_IFADDRS
339 // Network interfaces
340 struct ifaddrs *ifad = nullptr;
341 getifaddrs(&ifad);
342 struct ifaddrs *ifit = ifad;
343 while (ifit != nullptr) {
344 hasher.Write((const unsigned char*)&ifit, sizeof(ifit));
345 hasher.Write((const unsigned char*)ifit->ifa_name, strlen(ifit->ifa_name) + 1);
346 hasher.Write((const unsigned char*)&ifit->ifa_flags, sizeof(ifit->ifa_flags));
347 AddSockaddr(hasher, ifit->ifa_addr);
348 AddSockaddr(hasher, ifit->ifa_netmask);
349 AddSockaddr(hasher, ifit->ifa_dstaddr);
350 ifit = ifit->ifa_next;
351 }
352 freeifaddrs(ifad);
353 #endif
354
355 #ifndef WIN32
356 // UNIX kernel information
357 struct utsname name;
358 if (uname(&name) != -1) {
359 hasher.Write((const unsigned char*)&name.sysname, strlen(name.sysname) + 1);
360 hasher.Write((const unsigned char*)&name.nodename, strlen(name.nodename) + 1);
361 hasher.Write((const unsigned char*)&name.release, strlen(name.release) + 1);
362 hasher.Write((const unsigned char*)&name.version, strlen(name.version) + 1);
363 hasher.Write((const unsigned char*)&name.machine, strlen(name.machine) + 1);
364 }
365
366 /* Path and filesystem provided data */
367 AddPath(hasher, "/");
368 AddPath(hasher, ".");
369 AddPath(hasher, "/tmp");
370 AddPath(hasher, "/home");
371 AddPath(hasher, "/proc");
372 #ifdef __linux__
373 AddFile(hasher, "/proc/cmdline");
374 AddFile(hasher, "/proc/cpuinfo");
375 AddFile(hasher, "/proc/version");
376 #endif
377 AddFile(hasher, "/etc/passwd");
378 AddFile(hasher, "/etc/group");
379 AddFile(hasher, "/etc/hosts");
380 AddFile(hasher, "/etc/resolv.conf");
381 AddFile(hasher, "/etc/timezone");
382 AddFile(hasher, "/etc/localtime");
383 #endif
384
385 // For MacOS/BSDs, gather data through sysctl instead of /proc. Not all of these
386 // will exist on every system.
387 #ifdef HAVE_SYSCTL
388 # ifdef CTL_HW
389 # ifdef HW_MACHINE
390 AddSysctl<CTL_HW, HW_MACHINE>(hasher);
391 # endif
392 # ifdef HW_MODEL
393 AddSysctl<CTL_HW, HW_MODEL>(hasher);
394 # endif
395 # ifdef HW_NCPU
396 AddSysctl<CTL_HW, HW_NCPU>(hasher);
397 # endif
398 # ifdef HW_PHYSMEM
399 AddSysctl<CTL_HW, HW_PHYSMEM>(hasher);
400 # endif
401 # ifdef HW_USERMEM
402 AddSysctl<CTL_HW, HW_USERMEM>(hasher);
403 # endif
404 # ifdef HW_MACHINE_ARCH
405 AddSysctl<CTL_HW, HW_MACHINE_ARCH>(hasher);
406 # endif
407 # ifdef HW_REALMEM
408 AddSysctl<CTL_HW, HW_REALMEM>(hasher);
409 # endif
410 # ifdef HW_CPU_FREQ
411 AddSysctl<CTL_HW, HW_CPU_FREQ>(hasher);
412 # endif
413 # ifdef HW_BUS_FREQ
414 AddSysctl<CTL_HW, HW_BUS_FREQ>(hasher);
415 # endif
416 # ifdef HW_CACHELINE
417 AddSysctl<CTL_HW, HW_CACHELINE>(hasher);
418 # endif
419 # endif
420 # ifdef CTL_KERN
421 # ifdef KERN_BOOTFILE
422 AddSysctl<CTL_KERN, KERN_BOOTFILE>(hasher);
423 # endif
424 # ifdef KERN_BOOTTIME
425 AddSysctl<CTL_KERN, KERN_BOOTTIME>(hasher);
426 # endif
427 # ifdef KERN_CLOCKRATE
428 AddSysctl<CTL_KERN, KERN_CLOCKRATE>(hasher);
429 # endif
430 # ifdef KERN_HOSTID
431 AddSysctl<CTL_KERN, KERN_HOSTID>(hasher);
432 # endif
433 # ifdef KERN_HOSTUUID
434 AddSysctl<CTL_KERN, KERN_HOSTUUID>(hasher);
435 # endif
436 # ifdef KERN_HOSTNAME
437 AddSysctl<CTL_KERN, KERN_HOSTNAME>(hasher);
438 # endif
439 # ifdef KERN_OSRELDATE
440 AddSysctl<CTL_KERN, KERN_OSRELDATE>(hasher);
441 # endif
442 # ifdef KERN_OSRELEASE
443 AddSysctl<CTL_KERN, KERN_OSRELEASE>(hasher);
444 # endif
445 # ifdef KERN_OSREV
446 AddSysctl<CTL_KERN, KERN_OSREV>(hasher);
447 # endif
448 # ifdef KERN_OSTYPE
449 AddSysctl<CTL_KERN, KERN_OSTYPE>(hasher);
450 # endif
451 # ifdef KERN_POSIX1
452 AddSysctl<CTL_KERN, KERN_OSREV>(hasher);
453 # endif
454 # ifdef KERN_VERSION
455 AddSysctl<CTL_KERN, KERN_VERSION>(hasher);
456 # endif
457 # endif
458 #endif
459
460 // Env variables
461 if (environ) {
462 for (size_t i = 0; environ[i]; ++i) {
463 hasher.Write((const unsigned char*)environ[i], strlen(environ[i]));
464 }
465 }
466
467 // Process, thread, user, session, group, ... ids.
468 #ifdef WIN32
469 hasher << GetCurrentProcessId() << GetCurrentThreadId();
470 #else
471 hasher << getpid() << getppid() << getsid(0) << getpgid(0) << getuid() << geteuid() << getgid() << getegid();
472 #endif
473 hasher << std::this_thread::get_id();
474 }
475