1 files changed, 63 insertions, 0 deletions
diff --git a/src/Crypto/chachaRng.h b/src/Crypto/chachaRng.h
new file mode 100644
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--- /dev/null
+++ b/src/Crypto/chachaRng.h
@@ -0,0 +1,63 @@
+/*	$OpenBSD: arc4random.c,v 1.54 2015/09/13 08:31:47 guenther Exp $	*/
+
+/*
+ * Copyright (c) 1996, David Mazieres <dm@uun.org>
+ * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
+ * Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
+ * Copyright (c) 2014, Theo de Raadt <deraadt@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * ChaCha based random number generator for OpenBSD.
+ */
+
+/*
+ * Adapted for VeraCrypt
+ */
+
+#ifndef HEADER_Crypto_ChaChaRng
+#define HEADER_Crypto_ChaChaRng
+
+#include "chacha256.h"
+
+#define CHACHA20RNG_KEYSZ	32
+#define CHACHA20RNG_IVSZ	8
+#define CHACHA20RNG_BLOCKSZ	64
+#define CHACHA20RNG_RSBUFSZ	(16*CHACHA20RNG_BLOCKSZ)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void (*GetRandSeedFn)(unsigned char* pbRandSeed, size_t cbRandSeed);
+
+typedef struct
+{
+	ChaCha256Ctx m_chachaCtx; /* ChaCha20 context */
+	unsigned char m_rs_buf[CHACHA20RNG_RSBUFSZ];	/* keystream blocks */
+	size_t m_rs_have;	/* valid bytes at end of rs_buf */
+	size_t m_rs_count; /* bytes till reseed */
+	GetRandSeedFn m_getRandSeedCallback;
+} ChaCha20RngCtx;
+
+/*  key length must be equal to 40 bytes (CHACHA20RNG_KEYSZ + CHACHA20RNG_IVSZ) */
+void ChaCha20RngInit (ChaCha20RngCtx* pCtx, const unsigned char* key, GetRandSeedFn rngCallback, size_t InitialBytesToSkip);
+void ChaCha20RngGetBytes (ChaCha20RngCtx* pCtx, unsigned char* buffer, size_t bufferLen);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif