python36/00250-getentropy.patch

172 lines
4.4 KiB
Diff

diff -r ee1390c9b585 Python/random.c
--- a/Python/random.c Wed Jan 04 12:02:30 2017 +0100
+++ b/Python/random.c Wed Jan 04 18:32:21 2017 +0100
@@ -77,45 +77,8 @@ win32_urandom(unsigned char *buffer, Py_
return 0;
}
-/* Issue #25003: Don't use getentropy() on Solaris (available since
- * Solaris 11.3), it is blocking whereas os.urandom() should not block. */
-#elif defined(HAVE_GETENTROPY) && !defined(sun)
-#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 raise is zero, don't raise an exception on error. */
-static int
-py_getentropy(char *buffer, Py_ssize_t size, int raise)
-{
- while (size > 0) {
- Py_ssize_t len = Py_MIN(size, 256);
- int res;
+#else /* !MS_WINDOWS */
- if (raise) {
- Py_BEGIN_ALLOW_THREADS
- res = getentropy(buffer, len);
- Py_END_ALLOW_THREADS
- }
- else {
- res = getentropy(buffer, len);
- }
-
- if (res < 0) {
- if (raise) {
- PyErr_SetFromErrno(PyExc_OSError);
- }
- return -1;
- }
-
- buffer += len;
- size -= len;
- }
- return 0;
-}
-
-#else
#if defined(HAVE_GETRANDOM) || defined(HAVE_GETRANDOM_SYSCALL)
#define PY_GETRANDOM 1
@@ -217,6 +180,59 @@ py_getrandom(void *buffer, Py_ssize_t si
}
return 1;
}
+
+/* Issue #25003: Don't use getentropy() on Solaris (available since
+ * Solaris 11.3), it is blocking whereas os.urandom() should not block. */
+#elif defined(HAVE_GETENTROPY) && !defined(sun)
+#define PY_GETENTROPY 1
+
+/* Fill buffer with size pseudo-random bytes generated by getentropy().
+ Return 1 on success, or raise an exception and return -1 on error.
+
+ If raise is zero, don't raise an exception on error. */
+static int
+py_getentropy(char *buffer, Py_ssize_t size, int raise)
+{
+ /* Is getentropy() supported by the running kernel? Set to 0 if
+ getentropy() failed with ENOSYS. */
+ static int getentropy_works = 1;
+
+ if (!getentropy_works) {
+ return 0;
+ }
+
+ while (size > 0) {
+ Py_ssize_t len = Py_MIN(size, 256);
+ int res;
+
+ if (raise) {
+ Py_BEGIN_ALLOW_THREADS
+ res = getentropy(buffer, len);
+ Py_END_ALLOW_THREADS
+ }
+ else {
+ res = getentropy(buffer, len);
+ }
+
+ if (res < 0) {
+ /* ENOSYS: the inner syscall is not supported by the running
+ kernel. */
+ if (errno == ENOSYS) {
+ getentropy_works = 0;
+ return 0;
+ }
+
+ if (raise) {
+ PyErr_SetFromErrno(PyExc_OSError);
+ }
+ return -1;
+ }
+
+ buffer += len;
+ size -= len;
+ }
+ return 1;
+}
#endif
static struct {
@@ -236,7 +252,7 @@ dev_urandom(char *buffer, Py_ssize_t siz
{
int fd;
Py_ssize_t n;
-#ifdef PY_GETRANDOM
+#if defined(PY_GETRANDOM) || defined(PY_GETENTROPY)
int res;
#endif
@@ -244,17 +260,20 @@ dev_urandom(char *buffer, Py_ssize_t siz
#ifdef PY_GETRANDOM
res = py_getrandom(buffer, size, blocking, raise);
+#elif defined(PY_GETENTROPY)
+ res = py_getentropy(buffer, size, raise);
+#endif
+#if defined(PY_GETRANDOM) || defined(PY_GETENTROPY)
if (res < 0) {
return -1;
}
if (res == 1) {
return 0;
}
- /* getrandom() failed with ENOSYS or EPERM,
- fall back on reading /dev/urandom */
+ /* function failed with ENOSYS or EPERM, fall back on reading
+ from /dev/urandom */
#endif
-
if (raise) {
struct _Py_stat_struct st;
@@ -349,8 +368,8 @@ dev_urandom_close(void)
urandom_cache.fd = -1;
}
}
+#endif /* !MS_WINDOWS */
-#endif
/* Fill buffer with pseudo-random bytes generated by a linear congruent
generator (LCG):
@@ -395,8 +414,6 @@ pyurandom(void *buffer, Py_ssize_t size,
#ifdef MS_WINDOWS
return win32_urandom((unsigned char *)buffer, size, raise);
-#elif defined(PY_GETENTROPY)
- return py_getentropy(buffer, size, raise);
#else
return dev_urandom(buffer, size, blocking, raise);
#endif
@@ -491,8 +508,6 @@ void
CryptReleaseContext(hCryptProv, 0);
hCryptProv = 0;
}
-#elif defined(PY_GETENTROPY)
- /* nothing to clean */
#else
dev_urandom_close();
#endif