diff --git a/Misc/NEWS b/Misc/NEWS index 827d7882860..77efd05f913 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -10,6 +10,11 @@ Release date: XXXX-XX-XX Core and Builtins ----------------- +- Issue #25003: On Solaris 11.3 or newer, os.urandom() now uses the + getrandom() function instead of the getentropy() function. The getentropy() + function is blocking to generate very good quality entropy, os.urandom() + doesn't need such high-quality entropy. + - Issue #9232: Modify Python's grammar to allow trailing commas in the argument list of a function declaration. For example, "def f(*, a = 3,): pass" is now legal. Patch from Mark Dickinson. diff --git a/Python/random.c b/Python/random.c index ea09e84a7b0..8f3e6d60219 100644 --- a/Python/random.c +++ b/Python/random.c @@ -6,7 +6,9 @@ # ifdef HAVE_SYS_STAT_H # include # endif -# ifdef HAVE_GETRANDOM_SYSCALL +# ifdef HAVE_GETRANDOM +# include +# elif defined(HAVE_GETRANDOM_SYSCALL) # include # endif #endif @@ -70,7 +72,9 @@ win32_urandom(unsigned char *buffer, Py_ssize_t size, int raise) return 0; } -#elif HAVE_GETENTROPY +#elif defined(HAVE_GETENTROPY) && !defined(sun) +#define PY_GETENTROPY + /* Fill buffer with size pseudo-random bytes generated by getentropy(). Return 0 on success, or raise an exception and return -1 on error. @@ -105,16 +109,19 @@ py_getentropy(unsigned char *buffer, Py_ssize_t size, int fatal) return 0; } -#else /* !HAVE_GETENTROPY */ +#else + +#if defined(HAVE_GETRANDOM) || defined(HAVE_GETRANDOM_SYSCALL) +#define PY_GETRANDOM -#ifdef HAVE_GETRANDOM_SYSCALL static int py_getrandom(void *buffer, Py_ssize_t size, int raise) { - /* is getrandom() supported by the running kernel? - * need Linux kernel 3.17 or later */ + /* Is getrandom() supported by the running kernel? + * Need Linux kernel 3.17 or newer, or Solaris 11.3 or newer */ static int getrandom_works = 1; - /* Use /dev/urandom, block if the kernel has no entropy */ + /* Use non-blocking /dev/urandom device. On Linux at boot, the getrandom() + * syscall blocks until /dev/urandom is initialized with enough entropy. */ const int flags = 0; int n; @@ -124,7 +131,18 @@ py_getrandom(void *buffer, Py_ssize_t size, int raise) while (0 < size) { errno = 0; - /* Use syscall() because the libc doesn't expose getrandom() yet, see: +#ifdef HAVE_GETRANDOM + if (raise) { + Py_BEGIN_ALLOW_THREADS + n = getrandom(buffer, size, flags); + Py_END_ALLOW_THREADS + } + else { + n = getrandom(buffer, size, flags); + } +#else + /* On Linux, use the syscall() function because the GNU libc doesn't + * expose the Linux getrandom() syscall yet. See: * https://sourceware.org/bugzilla/show_bug.cgi?id=17252 */ if (raise) { Py_BEGIN_ALLOW_THREADS @@ -134,6 +152,7 @@ py_getrandom(void *buffer, Py_ssize_t size, int raise) else { n = syscall(SYS_getrandom, buffer, size, flags); } +#endif if (n < 0) { if (errno == ENOSYS) { @@ -182,7 +201,7 @@ dev_urandom_noraise(unsigned char *buffer, Py_ssize_t size) assert (0 < size); -#ifdef HAVE_GETRANDOM_SYSCALL +#ifdef PY_GETRANDOM if (py_getrandom(buffer, size, 0) == 1) return; /* getrandom() is not supported by the running kernel, fall back @@ -218,14 +237,14 @@ dev_urandom_python(char *buffer, Py_ssize_t size) int fd; Py_ssize_t n; struct _Py_stat_struct st; -#ifdef HAVE_GETRANDOM_SYSCALL +#ifdef PY_GETRANDOM int res; #endif if (size <= 0) return 0; -#ifdef HAVE_GETRANDOM_SYSCALL +#ifdef PY_GETRANDOM res = py_getrandom(buffer, size, 1); if (res < 0) return -1; @@ -304,7 +323,7 @@ dev_urandom_close(void) } } -#endif /* HAVE_GETENTROPY */ +#endif /* Fill buffer with pseudo-random bytes generated by a linear congruent generator (LCG): @@ -345,7 +364,7 @@ _PyOS_URandom(void *buffer, Py_ssize_t size) #ifdef MS_WINDOWS return win32_urandom((unsigned char *)buffer, size, 1); -#elif HAVE_GETENTROPY +#elif PY_GETENTROPY return py_getentropy(buffer, size, 0); #else return dev_urandom_python((char*)buffer, size); @@ -392,7 +411,7 @@ _PyRandom_Init(void) else { #ifdef MS_WINDOWS (void)win32_urandom(secret, secret_size, 0); -#elif HAVE_GETENTROPY +#elif PY_GETENTROPY (void)py_getentropy(secret, secret_size, 1); #else dev_urandom_noraise(secret, secret_size); @@ -408,7 +427,7 @@ _PyRandom_Fini(void) CryptReleaseContext(hCryptProv, 0); hCryptProv = 0; } -#elif HAVE_GETENTROPY +#elif PY_GETENTROPY /* nothing to clean */ #else dev_urandom_close(); diff --git a/configure b/configure index 95d953ac3da..f7b1839c193 100755 --- a/configure +++ b/configure @@ -16005,11 +16005,11 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext #include int main() { - const int flags = 0; char buffer[1]; - int n; + const size_t buflen = sizeof(buffer); + const int flags = 0; /* ignore the result, Python checks for ENOSYS at runtime */ - (void)syscall(SYS_getrandom, buffer, sizeof(buffer), flags); + (void)syscall(SYS_getrandom, buffer, buflen, flags); return 0; } @@ -16031,6 +16031,43 @@ $as_echo "#define HAVE_GETRANDOM_SYSCALL 1" >>confdefs.h fi +# check if the getrandom() function is available +# the test was written for the Solaris function of +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for the getrandom() function" >&5 +$as_echo_n "checking for the getrandom() function... " >&6; } +cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + + + #include + + int main() { + char buffer[1]; + const size_t buflen = sizeof(buffer); + const int flags = 0; + /* ignore the result, Python checks for ENOSYS at runtime */ + (void)getrandom(buffer, buflen, flags); + return 0; + } + + +_ACEOF +if ac_fn_c_try_link "$LINENO"; then : + have_getrandom=yes +else + have_getrandom=no +fi +rm -f core conftest.err conftest.$ac_objext \ + conftest$ac_exeext conftest.$ac_ext +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $have_getrandom" >&5 +$as_echo "$have_getrandom" >&6; } + +if test "$have_getrandom" = yes; then + +$as_echo "#define HAVE_GETRANDOM 1" >>confdefs.h + +fi + # generate output files ac_config_files="$ac_config_files Makefile.pre Modules/Setup.config Misc/python.pc Misc/python-config.sh" diff --git a/configure.ac b/configure.ac index 668234d7e2e..180a421f707 100644 --- a/configure.ac +++ b/configure.ac @@ -5111,11 +5111,11 @@ AC_LINK_IFELSE( #include int main() { - const int flags = 0; char buffer[1]; - int n; + const size_t buflen = sizeof(buffer); + const int flags = 0; /* ignore the result, Python checks for ENOSYS at runtime */ - (void)syscall(SYS_getrandom, buffer, sizeof(buffer), flags); + (void)syscall(SYS_getrandom, buffer, buflen, flags); return 0; } ]]) @@ -5127,6 +5127,31 @@ if test "$have_getrandom_syscall" = yes; then [Define to 1 if the Linux getrandom() syscall is available]) fi +# check if the getrandom() function is available +# the test was written for the Solaris function of +AC_MSG_CHECKING(for the getrandom() function) +AC_LINK_IFELSE( +[ + AC_LANG_SOURCE([[ + #include + + int main() { + char buffer[1]; + const size_t buflen = sizeof(buffer); + const int flags = 0; + /* ignore the result, Python checks for ENOSYS at runtime */ + (void)getrandom(buffer, buflen, flags); + return 0; + } + ]]) +],[have_getrandom=yes],[have_getrandom=no]) +AC_MSG_RESULT($have_getrandom) + +if test "$have_getrandom" = yes; then + AC_DEFINE(HAVE_GETRANDOM, 1, + [Define to 1 if the getrandom() function is available]) +fi + # generate output files AC_CONFIG_FILES(Makefile.pre Modules/Setup.config Misc/python.pc Misc/python-config.sh) AC_CONFIG_FILES([Modules/ld_so_aix], [chmod +x Modules/ld_so_aix]) diff --git a/pyconfig.h.in b/pyconfig.h.in index 0d40c94cd4c..b0cafb31857 100644 --- a/pyconfig.h.in +++ b/pyconfig.h.in @@ -395,6 +395,9 @@ /* Define to 1 if you have the `getpwent' function. */ #undef HAVE_GETPWENT +/* Define to 1 if the getrandom() function is available */ +#undef HAVE_GETRANDOM + /* Define to 1 if the Linux getrandom() syscall is available */ #undef HAVE_GETRANDOM_SYSCALL