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authornkozlovskiy <nmk@ydb.tech>2023-09-29 12:24:06 +0300
committernkozlovskiy <nmk@ydb.tech>2023-09-29 12:41:34 +0300
commite0e3e1717e3d33762ce61950504f9637a6e669ed (patch)
treebca3ff6939b10ed60c3d5c12439963a1146b9711 /contrib/tools/python/src/Python/random.c
parent38f2c5852db84c7b4d83adfcb009eb61541d1ccd (diff)
downloadydb-e0e3e1717e3d33762ce61950504f9637a6e669ed.tar.gz
add ydb deps
Diffstat (limited to 'contrib/tools/python/src/Python/random.c')
-rw-r--r--contrib/tools/python/src/Python/random.c435
1 files changed, 435 insertions, 0 deletions
diff --git a/contrib/tools/python/src/Python/random.c b/contrib/tools/python/src/Python/random.c
new file mode 100644
index 0000000000..d80ff40523
--- /dev/null
+++ b/contrib/tools/python/src/Python/random.c
@@ -0,0 +1,435 @@
+#include "Python.h"
+#ifdef MS_WINDOWS
+#include <windows.h>
+#include <wincrypt.h>
+#else
+#include <fcntl.h>
+#if defined(HAVE_SYS_RANDOM_H) && (defined(HAVE_GETRANDOM) || defined(HAVE_GETENTROPY))
+#include <sys/random.h>
+#endif
+#endif
+
+#ifdef Py_DEBUG
+int _Py_HashSecret_Initialized = 0;
+#else
+static int _Py_HashSecret_Initialized = 0;
+#endif
+
+#ifdef MS_WINDOWS
+typedef BOOL (WINAPI *CRYPTACQUIRECONTEXTA)(HCRYPTPROV *phProv,\
+ LPCSTR pszContainer, LPCSTR pszProvider, DWORD dwProvType,\
+ DWORD dwFlags );
+typedef BOOL (WINAPI *CRYPTGENRANDOM)(HCRYPTPROV hProv, DWORD dwLen,\
+ BYTE *pbBuffer );
+
+static CRYPTGENRANDOM pCryptGenRandom = NULL;
+/* This handle is never explicitly released. Instead, the operating
+ system will release it when the process terminates. */
+static HCRYPTPROV hCryptProv = 0;
+
+static int
+win32_urandom_init(int raise)
+{
+ HINSTANCE hAdvAPI32 = NULL;
+ CRYPTACQUIRECONTEXTA pCryptAcquireContext = NULL;
+
+ /* Obtain handle to the DLL containing CryptoAPI. This should not fail. */
+ hAdvAPI32 = GetModuleHandle("advapi32.dll");
+ if(hAdvAPI32 == NULL)
+ goto error;
+
+ /* Obtain pointers to the CryptoAPI functions. This will fail on some early
+ versions of Win95. */
+ pCryptAcquireContext = (CRYPTACQUIRECONTEXTA)GetProcAddress(
+ hAdvAPI32, "CryptAcquireContextA");
+ if (pCryptAcquireContext == NULL)
+ goto error;
+
+ pCryptGenRandom = (CRYPTGENRANDOM)GetProcAddress(hAdvAPI32,
+ "CryptGenRandom");
+ if (pCryptGenRandom == NULL)
+ goto error;
+
+ /* Acquire context */
+ if (! pCryptAcquireContext(&hCryptProv, NULL, NULL,
+ PROV_RSA_FULL, CRYPT_VERIFYCONTEXT))
+ goto error;
+
+ return 0;
+
+error:
+ if (raise)
+ PyErr_SetFromWindowsErr(0);
+ else
+ Py_FatalError("Failed to initialize Windows random API (CryptoGen)");
+ return -1;
+}
+
+/* Fill buffer with size pseudo-random bytes generated by the Windows CryptoGen
+ API. Return 0 on success, or -1 on error. */
+static int
+win32_urandom(unsigned char *buffer, Py_ssize_t size, int raise)
+{
+ Py_ssize_t chunk;
+
+ if (hCryptProv == 0)
+ {
+ if (win32_urandom_init(raise) == -1)
+ return -1;
+ }
+
+ while (size > 0)
+ {
+ chunk = size > INT_MAX ? INT_MAX : size;
+ if (!pCryptGenRandom(hCryptProv, chunk, buffer))
+ {
+ /* CryptGenRandom() failed */
+ if (raise)
+ PyErr_SetFromWindowsErr(0);
+ else
+ Py_FatalError("Failed to initialized the randomized hash "
+ "secret using CryptoGen)");
+ return -1;
+ }
+ buffer += chunk;
+ size -= chunk;
+ }
+ return 0;
+}
+
+/* Issue #25003: Don't use getentropy() on Solaris (available since
+ Solaris 11.3), it is blocking whereas os.urandom() should not block.
+
+ Issue #29188: Don't use getentropy() on Linux since the glibc 2.24
+ implements it with the getrandom() syscall which can fail with ENOSYS,
+ and this error is not supported in py_getentropy() and getrandom() is called
+ with flags=0 which blocks until system urandom is initialized, which is not
+ the desired behaviour to seed the Python hash secret nor for os.urandom():
+ see the PEP 524 which was only implemented in Python 3.6. */
+#elif defined(HAVE_GETENTROPY) && !defined(sun) && !defined(linux)
+#define PY_GETENTROPY 1
+
+/* Fill buffer with size pseudo-random bytes generated by getentropy().
+ Return 0 on success, or raise an exception and return -1 on error.
+ If fatal is nonzero, call Py_FatalError() instead of raising an exception
+ on error. */
+static int
+py_getentropy(unsigned char *buffer, Py_ssize_t size, int fatal)
+{
+ while (size > 0) {
+ Py_ssize_t len = size < 256 ? size : 256;
+ int res;
+
+ if (!fatal) {
+ Py_BEGIN_ALLOW_THREADS
+ res = getentropy(buffer, len);
+ Py_END_ALLOW_THREADS
+
+ if (res < 0) {
+ PyErr_SetFromErrno(PyExc_OSError);
+ return -1;
+ }
+ }
+ else {
+ res = getentropy(buffer, len);
+ if (res < 0)
+ Py_FatalError("getentropy() failed");
+ }
+
+ buffer += len;
+ size -= len;
+ }
+ return 0;
+}
+#endif
+
+#ifdef __VMS
+/* Use openssl random routine */
+#include <openssl/rand.h>
+static int
+vms_urandom(unsigned char *buffer, Py_ssize_t size, int raise)
+{
+ if (RAND_pseudo_bytes(buffer, size) < 0) {
+ if (raise) {
+ PyErr_Format(PyExc_ValueError,
+ "RAND_pseudo_bytes");
+ } else {
+ Py_FatalError("Failed to initialize the randomized hash "
+ "secret using RAND_pseudo_bytes");
+ }
+ return -1;
+ }
+ return 0;
+}
+#endif /* __VMS */
+
+
+#if !defined(MS_WINDOWS) && !defined(__VMS)
+
+static struct {
+ int fd;
+ dev_t st_dev;
+ ino_t st_ino;
+} urandom_cache = { -1 };
+
+/* Read size bytes from /dev/urandom into buffer.
+ Call Py_FatalError() on error. */
+static void
+dev_urandom_noraise(unsigned char *buffer, Py_ssize_t size)
+{
+ int fd;
+ Py_ssize_t n;
+
+ assert (0 < size);
+
+ fd = open("/dev/urandom", O_RDONLY);
+ if (fd < 0)
+ Py_FatalError("Failed to open /dev/urandom");
+
+ while (0 < size)
+ {
+ do {
+ n = read(fd, buffer, (size_t)size);
+ } while (n < 0 && errno == EINTR);
+ if (n <= 0)
+ {
+ /* stop on error or if read(size) returned 0 */
+ Py_FatalError("Failed to read bytes from /dev/urandom");
+ break;
+ }
+ buffer += n;
+ size -= (Py_ssize_t)n;
+ }
+ close(fd);
+}
+
+/* Read size bytes from /dev/urandom into buffer.
+ Return 0 on success, raise an exception and return -1 on error. */
+static int
+dev_urandom_python(char *buffer, Py_ssize_t size)
+{
+ int fd;
+ Py_ssize_t n;
+ struct stat st;
+ int attr;
+
+ if (size <= 0)
+ return 0;
+
+ if (urandom_cache.fd >= 0) {
+ /* Does the fd point to the same thing as before? (issue #21207) */
+ if (fstat(urandom_cache.fd, &st)
+ || st.st_dev != urandom_cache.st_dev
+ || st.st_ino != urandom_cache.st_ino) {
+ /* Something changed: forget the cached fd (but don't close it,
+ since it probably points to something important for some
+ third-party code). */
+ urandom_cache.fd = -1;
+ }
+ }
+ if (urandom_cache.fd >= 0)
+ fd = urandom_cache.fd;
+ else {
+ Py_BEGIN_ALLOW_THREADS
+ fd = open("/dev/urandom", O_RDONLY);
+ Py_END_ALLOW_THREADS
+ if (fd < 0)
+ {
+ if (errno == ENOENT || errno == ENXIO ||
+ errno == ENODEV || errno == EACCES)
+ PyErr_SetString(PyExc_NotImplementedError,
+ "/dev/urandom (or equivalent) not found");
+ else
+ PyErr_SetFromErrno(PyExc_OSError);
+ return -1;
+ }
+
+ /* try to make the file descriptor non-inheritable, ignore errors */
+ attr = fcntl(fd, F_GETFD);
+ if (attr >= 0) {
+ attr |= FD_CLOEXEC;
+ (void)fcntl(fd, F_SETFD, attr);
+ }
+
+ if (urandom_cache.fd >= 0) {
+ /* urandom_fd was initialized by another thread while we were
+ not holding the GIL, keep it. */
+ close(fd);
+ fd = urandom_cache.fd;
+ }
+ else {
+ if (fstat(fd, &st)) {
+ PyErr_SetFromErrno(PyExc_OSError);
+ close(fd);
+ return -1;
+ }
+ else {
+ urandom_cache.fd = fd;
+ urandom_cache.st_dev = st.st_dev;
+ urandom_cache.st_ino = st.st_ino;
+ }
+ }
+ }
+
+ Py_BEGIN_ALLOW_THREADS
+ do {
+ do {
+ n = read(fd, buffer, (size_t)size);
+ } while (n < 0 && errno == EINTR);
+ if (n <= 0)
+ break;
+ buffer += n;
+ size -= (Py_ssize_t)n;
+ } while (0 < size);
+ Py_END_ALLOW_THREADS
+
+ if (n <= 0)
+ {
+ /* stop on error or if read(size) returned 0 */
+ if (n < 0)
+ PyErr_SetFromErrno(PyExc_OSError);
+ else
+ PyErr_Format(PyExc_RuntimeError,
+ "Failed to read %zi bytes from /dev/urandom",
+ size);
+ return -1;
+ }
+ return 0;
+}
+
+static void
+dev_urandom_close(void)
+{
+ if (urandom_cache.fd >= 0) {
+ close(urandom_cache.fd);
+ urandom_cache.fd = -1;
+ }
+}
+
+
+#endif /* !defined(MS_WINDOWS) && !defined(__VMS) */
+
+/* Fill buffer with pseudo-random bytes generated by a linear congruent
+ generator (LCG):
+
+ x(n+1) = (x(n) * 214013 + 2531011) % 2^32
+
+ Use bits 23..16 of x(n) to generate a byte. */
+static void
+lcg_urandom(unsigned int x0, unsigned char *buffer, size_t size)
+{
+ size_t index;
+ unsigned int x;
+
+ x = x0;
+ for (index=0; index < size; index++) {
+ x *= 214013;
+ x += 2531011;
+ /* modulo 2 ^ (8 * sizeof(int)) */
+ buffer[index] = (x >> 16) & 0xff;
+ }
+}
+
+/* Fill buffer with size pseudo-random bytes from the operating system random
+ number generator (RNG). It is suitable for most cryptographic purposes
+ except long living private keys for asymmetric encryption.
+
+ Return 0 on success, raise an exception and return -1 on error. */
+int
+_PyOS_URandom(void *buffer, Py_ssize_t size)
+{
+ if (size < 0) {
+ PyErr_Format(PyExc_ValueError,
+ "negative argument not allowed");
+ return -1;
+ }
+ if (size == 0)
+ return 0;
+
+#ifdef MS_WINDOWS
+ return win32_urandom((unsigned char *)buffer, size, 1);
+#elif defined(PY_GETENTROPY)
+ return py_getentropy(buffer, size, 0);
+#else
+# ifdef __VMS
+ return vms_urandom((unsigned char *)buffer, size, 1);
+# else
+ return dev_urandom_python((char*)buffer, size);
+# endif
+#endif
+}
+
+void
+_PyRandom_Init(void)
+{
+ char *env;
+ void *secret = &_Py_HashSecret;
+ Py_ssize_t secret_size = sizeof(_Py_HashSecret_t);
+
+ if (_Py_HashSecret_Initialized)
+ return;
+ _Py_HashSecret_Initialized = 1;
+
+ /*
+ By default, hash randomization is disabled, and only
+ enabled if PYTHONHASHSEED is set to non-empty or if
+ "-R" is provided at the command line:
+ */
+ if (!Py_HashRandomizationFlag) {
+ /* Disable the randomized hash: */
+ memset(secret, 0, secret_size);
+ return;
+ }
+
+ /*
+ Hash randomization is enabled. Generate a per-process secret,
+ using PYTHONHASHSEED if provided.
+ */
+
+ env = Py_GETENV("PYTHONHASHSEED");
+ if (env && *env != '\0' && strcmp(env, "random") != 0) {
+ char *endptr = env;
+ unsigned long seed;
+ seed = strtoul(env, &endptr, 10);
+ if (*endptr != '\0'
+ || seed > 4294967295UL
+ || (errno == ERANGE && seed == ULONG_MAX))
+ {
+ Py_FatalError("PYTHONHASHSEED must be \"random\" or an integer "
+ "in range [0; 4294967295]");
+ }
+ if (seed == 0) {
+ /* disable the randomized hash */
+ memset(secret, 0, secret_size);
+ }
+ else {
+ lcg_urandom(seed, (unsigned char*)secret, secret_size);
+ }
+ }
+ else {
+#ifdef MS_WINDOWS
+ (void)win32_urandom((unsigned char *)secret, secret_size, 0);
+#elif __VMS
+ vms_urandom((unsigned char *)secret, secret_size, 0);
+#elif defined(PY_GETENTROPY)
+ (void)py_getentropy(secret, secret_size, 1);
+#else
+ dev_urandom_noraise(secret, secret_size);
+#endif
+ }
+}
+
+void
+_PyRandom_Fini(void)
+{
+#ifdef MS_WINDOWS
+ if (hCryptProv) {
+ CryptReleaseContext(hCryptProv, 0);
+ hCryptProv = 0;
+ }
+#elif defined(PY_GETENTROPY)
+ /* nothing to clean */
+#else
+ dev_urandom_close();
+#endif
+}