Windows: Use Hardware RNG based on CPU timing jitter "Jitterentropy" by Stephan Mueller as a good alternative to RDRAND (http://www.chronox.de/jent.html, smueller@chronox.de)

2025-11-14 04:18:26 -06:00 · 2019-02-12 18:49:12 +01:00
parent a5943c07fb
commit 86f0fde6e7
12 changed files with 1084 additions and 5 deletions
--- a/src/Crypto/jitterentropy-base-user.h
+++ b/src/Crypto/jitterentropy-base-user.h
@@ -0,0 +1,136 @@
+/*
+ * Non-physical true random number generator based on timing jitter.
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2013
+ *
+ * License
+ * =======
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, and the entire permission notice in its entirety,
+ *    including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior
+ *    written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions.  (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ e USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ */
+
+/* Adapted for VeraCrypt */
+
+#pragma once
+
+#include "Common/Tcdefs.h"
+#include "misc.h"
+#include "cpu.h"
+#include <stdlib.h>
+#include <string.h>
+
+typedef uint64 __u64;
+
+#ifdef _MSC_VER
+
+typedef uint64 uint64_t;
+typedef int64 int64_t;
+
+#ifndef _UEFI
+#define CONFIG_CRYPTO_CPU_JITTERENTROPY_SECURE_MEMORY
+#endif
+
+#ifndef _UEFI
+typedef SSIZE_T ssize_t;
+#else
+#if CRYPTOPP_BOOL_X64
+typedef int64 ssize_t;
+#else
+typedef int32 ssize_t;
+#endif
+#endif
+
+static VC_INLINE void jent_get_nstime(__u64 *out)
+{
+	*out = __rdtsc();;
+}
+
+#else
+
+/* taken from Linux kernel */
+#if CRYPTOPP_BOOL_X64
+#define DECLARE_ARGS(val, low, high)    unsigned low, high
+#define EAX_EDX_VAL(val, low, high)     ((low) | ((__u64)(high) << 32))
+#define EAX_EDX_RET(val, low, high)     "=a" (low), "=d" (high)
+#else   
+#define DECLARE_ARGS(val, low, high)    unsigned long long val
+#define EAX_EDX_VAL(val, low, high)     (val)
+#define EAX_EDX_RET(val, low, high)     "=A" (val)
+#endif
+
+static VC_INLINE void jent_get_nstime(__u64 *out)
+{
+	DECLARE_ARGS(val, low, high);
+	asm volatile("rdtsc" : EAX_EDX_RET(val, low, high));
+	*out = EAX_EDX_VAL(val, low, high);
+}
+
+#endif
+
+static VC_INLINE void *jent_zalloc(size_t len)
+{
+	void *tmp = NULL;
+	tmp = TCalloc(len);
+	if(NULL != tmp)
+	{
+		memset(tmp, 0, len);
+#if defined(_WIN32) && !defined(TC_WINDOWS_DRIVER) && !defined(_UEFI)
+		VirtualLock (tmp, len);
+#endif
+	}
+	return tmp;
+}
+
+static VC_INLINE void jent_zfree(void *ptr, unsigned int len)
+{
+	if (len % 8)
+		burn(ptr, len);
+	else
+		FAST_ERASE64(ptr, len);
+#if defined(_WIN32) && !defined(TC_WINDOWS_DRIVER) && !defined(_UEFI)
+	VirtualUnlock (ptr, len);
+#endif
+	TCfree(ptr);
+}
+
+static VC_INLINE int jent_fips_enabled(void)
+{
+        return 0;
+}
+
+/* --- helpers needed in user space -- */
+
+#define rol64(x,n)	rotl64(x,n)
+
+
+