Use both getrandom() and /dev/urandom by default on Linux.
getrandom() is now used on Linux by default when using Linux >= 3.17
and glibc >= 2.25
GH:
#include "rand_lcl.h"
#include <stdio.h>
-#ifdef OPENSSL_RAND_SEED_GETRANDOM
-# include <linux/random.h>
-#endif
-
#if (defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_UEFI)) && \
!defined(OPENSSL_RAND_SEED_NONE)
# error "UEFI and VXWorks only support seeding NONE"
@@ -123,11 +119,19 @@ size_t RAND_POOL_acquire_entropy(RAND_POOL *pool)
# endif
# if defined(OPENSSL_RAND_SEED_OS)
-# if defined(DEVRANDOM)
-# define OPENSSL_RAND_SEED_DEVRANDOM
-# else
+# if !defined(DEVRANDOM)
# error "OS seeding requires DEVRANDOM to be configured"
# endif
+# define OPENSSL_RAND_SEED_DEVRANDOM
+# if defined(__GLIBC__) && defined(__GLIBC_PREREQ)
+# if __GLIBC_PREREQ(2, 25)
+# define OPENSSL_RAND_SEED_GETRANDOM
+# endif
+# endif
+# endif
+
+# ifdef OPENSSL_RAND_SEED_GETRANDOM
+# include <sys/random.h>
# endif
# if defined(OPENSSL_RAND_SEED_LIBRANDOM)
