diff options
Diffstat (limited to 'compat/getentropy_win.c')
| -rw-r--r-- | compat/getentropy_win.c | 27 |
1 files changed, 9 insertions, 18 deletions
diff --git a/compat/getentropy_win.c b/compat/getentropy_win.c index 2abeb27..64514b3 100644 --- a/compat/getentropy_win.c +++ b/compat/getentropy_win.c @@ -1,4 +1,4 @@ -/* $OpenBSD: getentropy_win.c,v 1.5 2016/08/07 03:27:21 tb Exp $ */ +/* $OpenBSD: getentropy_win.c,v 1.6 2020/11/11 10:41:24 bcook Exp $ */ /* * Copyright (c) 2014, Theo de Raadt <deraadt@openbsd.org> @@ -21,39 +21,30 @@ */ #include <windows.h> +#include <bcrypt.h> #include <errno.h> #include <stdint.h> #include <sys/types.h> -#include <wincrypt.h> -#include <process.h> int getentropy(void *buf, size_t len); /* - * On Windows, CryptGenRandom is supposed to be a well-seeded - * cryptographically strong random number generator. + * On Windows, BCryptGenRandom with BCRYPT_USE_SYSTEM_PREFERRED_RNG is supposed + * to be a well-seeded, cryptographically strong random number generator. + * https://docs.microsoft.com/en-us/windows/win32/api/bcrypt/nf-bcrypt-bcryptgenrandom */ int getentropy(void *buf, size_t len) { - HCRYPTPROV provider; - if (len > 256) { errno = EIO; return (-1); } - if (CryptAcquireContext(&provider, NULL, NULL, PROV_RSA_FULL, - CRYPT_VERIFYCONTEXT) == 0) - goto fail; - if (CryptGenRandom(provider, len, buf) == 0) { - CryptReleaseContext(provider, 0); - goto fail; + if (FAILED(BCryptGenRandom(NULL, buf, len, BCRYPT_USE_SYSTEM_PREFERRED_RNG))) { + errno = EIO; + return (-1); } - CryptReleaseContext(provider, 0); - return (0); -fail: - errno = EIO; - return (-1); + return (0); } |