diff --git a/Crypto/Scrypt.hs b/Crypto/Scrypt.hs
new file mode 100644
--- /dev/null
+++ b/Crypto/Scrypt.hs
@@ -0,0 +1,97 @@
+{-# LANGUAGE ForeignFunctionInterface, RecordWildCards, NamedFieldPuns #-}
+
+-- |Scrypt is a sequential memory-hard key derivation function. This module
+--  provides bindings to a fast C implementation of scrypt, written by Colin
+--  Percival. See <http://www.tarsnap.com/scrypt.html> for more information
+--  on scrypt.
+module Crypto.Scrypt
+    ( 
+    -- *Parameters to the @scrypt@ function
+     ScryptParams, params, defaultParams
+    -- * The @scrypt@ key derivation function
+    , scrypt, getSalt
+    , Pass(..), Salt(..), PassHash(..)
+    ) where
+
+import Control.Applicative ((<$>))
+import Data.ByteString
+import Data.Maybe
+import Foreign
+import Foreign.C
+import System.IO
+
+
+newtype Pass = Pass ByteString deriving (Show)
+newtype Salt = Salt ByteString deriving (Show)
+newtype PassHash = PassHash ByteString deriving (Show,Eq)
+
+-- |Encapsulates the three tuning parameters to the 'scrypt' function: @N@,
+--  @r@ and @p@. The parameters affect running time and memory usage:
+--
+--  /Memory usage/ is approximately @128*r*N@ bytes. Note that the
+--  'params' function takes @log_2(N)@ as a parameter. As an example, the
+--  'defaultParams'
+--  
+--  @   log_2(N) = 14, r = 8, and p = 1@
+--
+--  lead to 'scrypt' using @128 * 8 * 2^14 = 16M@ bytes of memory.
+--
+--  /Running time/ is proportional to all of @N@, @r@ and @p@. However
+--  @p@ only as an insignificant influence on memory usage an can thus be
+--  used to tune the running time of 'scrypt'.
+--
+data ScryptParams = Params { logN, r, p, bufLen :: Integer}
+
+-- |Constructor function for the 'ScryptParams' data type
+params :: Integer
+       -- ^ @log_2(N)@. Scrypt's @N@ parameter must be a power of two greater
+       -- than one, thus it's logarithm to base two must be greater than zero. 
+       -> Integer
+       -- ^ The parameter @r@, an integer greater than zero.
+       -> Integer
+       -- ^ The parameter @p@, an integer greater than zero. @r@ and @p@
+       --   must satisfy @r * p < 2^30@.
+       -> Maybe ScryptParams
+       -- ^ Returns 'Just' the parameter object for valid arguments,
+       --   otherwise 'Nothing'.
+params logN r p | valid     = Just ps
+                | otherwise = Nothing
+  where
+    ps    = Params { logN, r, p, bufLen = 64 }
+    valid = and [ logN > 0, r > 0, p > 0
+                , r*p < 2^(30 :: Int)
+                , bufLen ps <= 2^(32 :: Int)-1 * 32
+                ]
+
+-- |Default parameters as recommended in the scrypt paper:
+--
+--  @   N = 2^14, r = 8, p = 1 @
+--
+--  Equivalent to @'fromJust' ('params' 14 8 1)@.
+defaultParams :: ScryptParams
+defaultParams = fromJust (params 14 8 1)
+
+-- |Reads a 32-byte random salt from @\/dev\/urandom@.
+getSalt :: IO Salt
+getSalt = Salt <$> withBinaryFile "/dev/urandom" ReadMode (flip hGet 32)
+
+-- |Calculates a 64-byte hash from the given password, salt and parameters.
+scrypt :: ScryptParams -> Salt -> Pass -> PassHash
+scrypt Params{..} (Salt salt) (Pass pass) =
+    PassHash <$> unsafePerformIO $
+        useAsCStringLen salt $ \(saltPtr, saltLen) ->
+        useAsCStringLen pass $ \(passPtr, passLen) ->
+        allocaBytes (fromIntegral bufLen) $ \bufPtr -> do
+            throwErrnoIfMinus1_ "c_scrypt" $ c_scrypt
+                (castPtr passPtr) (fromIntegral passLen)
+                (castPtr saltPtr) (fromIntegral saltLen)
+                (2^logN) (fromIntegral r) (fromIntegral p)
+                bufPtr (fromIntegral bufLen)
+            packCStringLen (castPtr bufPtr, fromIntegral bufLen)
+
+foreign import ccall unsafe "crypto_scrypt" c_scrypt
+    :: Ptr Word8 -> CSize
+    -> Ptr Word8 -> CSize
+    -> Word64 -> Word32 -> Word32 -- N, r, p
+    -> Ptr Word8 -> CSize
+    -> IO CInt
diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c)2011, Falko Peters
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * 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.
+
+    * Neither the name of Falko Peters nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS 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 USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/README.markdown b/README.markdown
new file mode 100644
--- /dev/null
+++ b/README.markdown
@@ -0,0 +1,19 @@
+# Welcome to scrypt
+
+This is a Haskell library providing bindings to [Colin Percival's `scrypt` implementation](http://www.tarsnap.com/scrypt.html). Scrypt is a key derivation function designed to be far more secure against hardware brute-force attacks than alternative functions such as PBKDF2 or bcrypt.
+
+Details of the scrypt key derivation function are given in a paper by Colin Percival, Stronger Key Derivation via Sequential Memory-Hard Functions: [PDF](http://www.tarsnap.com/scrypt/scrypt-slides.pdf).
+
+# Join in!
+
+We are happy to receive bug reports, fixes, documentation enhancements, and other improvements.
+
+Please report bugs via the [github issue tracker](http://github.com/informatikr/scrypt/issues).
+
+Master [git repository](http://github.com/informatikr/scrypt):
+
+    git clone git://github.com/informatikr/scrypt.git
+
+# Authors
+
+This library is written and maintained by Falko Peters,  <falko.peters@gmail.com>.
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/cbits/crypto_scrypt-sse.c b/cbits/crypto_scrypt-sse.c
new file mode 100644
--- /dev/null
+++ b/cbits/crypto_scrypt-sse.c
@@ -0,0 +1,364 @@
+/*-
+ * Copyright 2009 Colin Percival
+ * All rights reserved.
+ *
+ * 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, this list of conditions and the following disclaimer.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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 USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file was originally written by Colin Percival as part of the Tarsnap
+ * online backup system.
+ */
+#include <sys/types.h>
+#include <sys/mman.h>
+
+#include <emmintrin.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "sha256.h"
+#include "sysendian.h"
+
+#include "crypto_scrypt.h"
+
+static void blkcpy(void *, void *, size_t);
+static void blkxor(void *, void *, size_t);
+static void salsa20_8(__m128i *);
+static void blockmix_salsa8(__m128i *, __m128i *, __m128i *, size_t);
+static uint64_t integerify(void *, size_t);
+static void smix(uint8_t *, size_t, uint64_t, void *, void *);
+
+static void
+blkcpy(void * dest, void * src, size_t len)
+{
+	__m128i * D = dest;
+	__m128i * S = src;
+	size_t L = len / 16;
+	size_t i;
+
+	for (i = 0; i < L; i++)
+		D[i] = S[i];
+}
+
+static void
+blkxor(void * dest, void * src, size_t len)
+{
+	__m128i * D = dest;
+	__m128i * S = src;
+	size_t L = len / 16;
+	size_t i;
+
+	for (i = 0; i < L; i++)
+		D[i] = _mm_xor_si128(D[i], S[i]);
+}
+
+/**
+ * salsa20_8(B):
+ * Apply the salsa20/8 core to the provided block.
+ */
+static void
+salsa20_8(__m128i B[4])
+{
+	__m128i X0, X1, X2, X3;
+	__m128i T;
+	size_t i;
+
+	X0 = B[0];
+	X1 = B[1];
+	X2 = B[2];
+	X3 = B[3];
+
+	for (i = 0; i < 8; i += 2) {
+		/* Operate on "columns". */
+		T = _mm_add_epi32(X0, X3);
+		X1 = _mm_xor_si128(X1, _mm_slli_epi32(T, 7));
+		X1 = _mm_xor_si128(X1, _mm_srli_epi32(T, 25));
+		T = _mm_add_epi32(X1, X0);
+		X2 = _mm_xor_si128(X2, _mm_slli_epi32(T, 9));
+		X2 = _mm_xor_si128(X2, _mm_srli_epi32(T, 23));
+		T = _mm_add_epi32(X2, X1);
+		X3 = _mm_xor_si128(X3, _mm_slli_epi32(T, 13));
+		X3 = _mm_xor_si128(X3, _mm_srli_epi32(T, 19));
+		T = _mm_add_epi32(X3, X2);
+		X0 = _mm_xor_si128(X0, _mm_slli_epi32(T, 18));
+		X0 = _mm_xor_si128(X0, _mm_srli_epi32(T, 14));
+
+		/* Rearrange data. */
+		X1 = _mm_shuffle_epi32(X1, 0x93);
+		X2 = _mm_shuffle_epi32(X2, 0x4E);
+		X3 = _mm_shuffle_epi32(X3, 0x39);
+
+		/* Operate on "rows". */
+		T = _mm_add_epi32(X0, X1);
+		X3 = _mm_xor_si128(X3, _mm_slli_epi32(T, 7));
+		X3 = _mm_xor_si128(X3, _mm_srli_epi32(T, 25));
+		T = _mm_add_epi32(X3, X0);
+		X2 = _mm_xor_si128(X2, _mm_slli_epi32(T, 9));
+		X2 = _mm_xor_si128(X2, _mm_srli_epi32(T, 23));
+		T = _mm_add_epi32(X2, X3);
+		X1 = _mm_xor_si128(X1, _mm_slli_epi32(T, 13));
+		X1 = _mm_xor_si128(X1, _mm_srli_epi32(T, 19));
+		T = _mm_add_epi32(X1, X2);
+		X0 = _mm_xor_si128(X0, _mm_slli_epi32(T, 18));
+		X0 = _mm_xor_si128(X0, _mm_srli_epi32(T, 14));
+
+		/* Rearrange data. */
+		X1 = _mm_shuffle_epi32(X1, 0x39);
+		X2 = _mm_shuffle_epi32(X2, 0x4E);
+		X3 = _mm_shuffle_epi32(X3, 0x93);
+	}
+
+	B[0] = _mm_add_epi32(B[0], X0);
+	B[1] = _mm_add_epi32(B[1], X1);
+	B[2] = _mm_add_epi32(B[2], X2);
+	B[3] = _mm_add_epi32(B[3], X3);
+}
+
+/**
+ * blockmix_salsa8(Bin, Bout, X, r):
+ * Compute Bout = BlockMix_{salsa20/8, r}(Bin).  The input Bin must be 128r
+ * bytes in length; the output Bout must also be the same size.  The
+ * temporary space X must be 64 bytes.
+ */
+static void
+blockmix_salsa8(__m128i * Bin, __m128i * Bout, __m128i * X, size_t r)
+{
+	size_t i;
+
+	/* 1: X <-- B_{2r - 1} */
+	blkcpy(X, &Bin[8 * r - 4], 64);
+
+	/* 2: for i = 0 to 2r - 1 do */
+	for (i = 0; i < r; i++) {
+		/* 3: X <-- H(X \xor B_i) */
+		blkxor(X, &Bin[i * 8], 64);
+		salsa20_8(X);
+
+		/* 4: Y_i <-- X */
+		/* 6: B' <-- (Y_0, Y_2 ... Y_{2r-2}, Y_1, Y_3 ... Y_{2r-1}) */
+		blkcpy(&Bout[i * 4], X, 64);
+
+		/* 3: X <-- H(X \xor B_i) */
+		blkxor(X, &Bin[i * 8 + 4], 64);
+		salsa20_8(X);
+
+		/* 4: Y_i <-- X */
+		/* 6: B' <-- (Y_0, Y_2 ... Y_{2r-2}, Y_1, Y_3 ... Y_{2r-1}) */
+		blkcpy(&Bout[(r + i) * 4], X, 64);
+	}
+}
+
+/**
+ * integerify(B, r):
+ * Return the result of parsing B_{2r-1} as a little-endian integer.
+ */
+static uint64_t
+integerify(void * B, size_t r)
+{
+	uint32_t * X = (void *)((uintptr_t)(B) + (2 * r - 1) * 64);
+
+	return (((uint64_t)(X[13]) << 32) + X[0]);
+}
+
+/**
+ * smix(B, r, N, V, XY):
+ * Compute B = SMix_r(B, N).  The input B must be 128r bytes in length;
+ * the temporary storage V must be 128rN bytes in length; the temporary
+ * storage XY must be 256r + 64 bytes in length.  The value N must be a
+ * power of 2 greater than 1.  The arrays B, V, and XY must be aligned to a
+ * multiple of 64 bytes.
+ */
+static void
+smix(uint8_t * B, size_t r, uint64_t N, void * V, void * XY)
+{
+	__m128i * X = XY;
+	__m128i * Y = (void *)((uintptr_t)(XY) + 128 * r);
+	__m128i * Z = (void *)((uintptr_t)(XY) + 256 * r);
+	uint32_t * X32 = (void *)X;
+	uint64_t i, j;
+	size_t k;
+
+	/* 1: X <-- B */
+	for (k = 0; k < 2 * r; k++) {
+		for (i = 0; i < 16; i++) {
+			X32[k * 16 + i] =
+			    le32dec(&B[(k * 16 + (i * 5 % 16)) * 4]);
+		}
+	}
+
+	/* 2: for i = 0 to N - 1 do */
+	for (i = 0; i < N; i += 2) {
+		/* 3: V_i <-- X */
+		blkcpy((void *)((uintptr_t)(V) + i * 128 * r), X, 128 * r);
+
+		/* 4: X <-- H(X) */
+		blockmix_salsa8(X, Y, Z, r);
+
+		/* 3: V_i <-- X */
+		blkcpy((void *)((uintptr_t)(V) + (i + 1) * 128 * r),
+		    Y, 128 * r);
+
+		/* 4: X <-- H(X) */
+		blockmix_salsa8(Y, X, Z, r);
+	}
+
+	/* 6: for i = 0 to N - 1 do */
+	for (i = 0; i < N; i += 2) {
+		/* 7: j <-- Integerify(X) mod N */
+		j = integerify(X, r) & (N - 1);
+
+		/* 8: X <-- H(X \xor V_j) */
+		blkxor(X, (void *)((uintptr_t)(V) + j * 128 * r), 128 * r);
+		blockmix_salsa8(X, Y, Z, r);
+
+		/* 7: j <-- Integerify(X) mod N */
+		j = integerify(Y, r) & (N - 1);
+
+		/* 8: X <-- H(X \xor V_j) */
+		blkxor(Y, (void *)((uintptr_t)(V) + j * 128 * r), 128 * r);
+		blockmix_salsa8(Y, X, Z, r);
+	}
+
+	/* 10: B' <-- X */
+	for (k = 0; k < 2 * r; k++) {
+		for (i = 0; i < 16; i++) {
+			le32enc(&B[(k * 16 + (i * 5 % 16)) * 4],
+			    X32[k * 16 + i]);
+		}
+	}
+}
+
+/**
+ * crypto_scrypt(passwd, passwdlen, salt, saltlen, N, r, p, buf, buflen):
+ * Compute scrypt(passwd[0 .. passwdlen - 1], salt[0 .. saltlen - 1], N, r,
+ * p, buflen) and write the result into buf.  The parameters r, p, and buflen
+ * must satisfy r * p < 2^30 and buflen <= (2^32 - 1) * 32.  The parameter N
+ * must be a power of 2 greater than 1.
+ *
+ * Return 0 on success; or -1 on error.
+ */
+int
+crypto_scrypt(const uint8_t * passwd, size_t passwdlen,
+    const uint8_t * salt, size_t saltlen, uint64_t N, uint32_t r, uint32_t p,
+    uint8_t * buf, size_t buflen)
+{
+	void * B0, * V0, * XY0;
+	uint8_t * B;
+	uint32_t * V;
+	uint32_t * XY;
+	uint32_t i;
+
+	/* Sanity-check parameters. */
+#if SIZE_MAX > UINT32_MAX
+	if (buflen > (((uint64_t)(1) << 32) - 1) * 32) {
+		errno = EFBIG;
+		goto err0;
+	}
+#endif
+	if ((uint64_t)(r) * (uint64_t)(p) >= (1 << 30)) {
+		errno = EFBIG;
+		goto err0;
+	}
+	if (((N & (N - 1)) != 0) || (N == 0)) {
+		errno = EINVAL;
+		goto err0;
+	}
+	if ((r > SIZE_MAX / 128 / p) ||
+#if SIZE_MAX / 256 <= UINT32_MAX
+	    (r > (SIZE_MAX - 64) / 256) ||
+#endif
+	    (N > SIZE_MAX / 128 / r)) {
+		errno = ENOMEM;
+		goto err0;
+	}
+
+	/* Allocate memory. */
+#ifdef HAVE_POSIX_MEMALIGN
+	if ((errno = posix_memalign(&B0, 64, 128 * r * p)) != 0)
+		goto err0;
+	B = (uint8_t *)(B0);
+	if ((errno = posix_memalign(&XY0, 64, 256 * r + 64)) != 0)
+		goto err1;
+	XY = (uint32_t *)(XY0);
+#ifndef MAP_ANON
+	if ((errno = posix_memalign(&V0, 64, 128 * r * N)) != 0)
+		goto err2;
+	V = (uint32_t *)(V0);
+#endif
+#else
+	if ((B0 = malloc(128 * r * p + 63)) == NULL)
+		goto err0;
+	B = (uint8_t *)(((uintptr_t)(B0) + 63) & ~ (uintptr_t)(63));
+	if ((XY0 = malloc(256 * r + 64 + 63)) == NULL)
+		goto err1;
+	XY = (uint32_t *)(((uintptr_t)(XY0) + 63) & ~ (uintptr_t)(63));
+#ifndef MAP_ANON
+	if ((V0 = malloc(128 * r * N + 63)) == NULL)
+		goto err2;
+	V = (uint32_t *)(((uintptr_t)(V0) + 63) & ~ (uintptr_t)(63));
+#endif
+#endif
+#ifdef MAP_ANON
+	if ((V0 = mmap(NULL, 128 * r * N, PROT_READ | PROT_WRITE,
+#ifdef MAP_NOCORE
+	    MAP_ANON | MAP_PRIVATE | MAP_NOCORE,
+#else
+	    MAP_ANON | MAP_PRIVATE,
+#endif
+	    -1, 0)) == MAP_FAILED)
+		goto err2;
+	V = (uint32_t *)(V0);
+#endif
+
+	/* 1: (B_0 ... B_{p-1}) <-- PBKDF2(P, S, 1, p * MFLen) */
+	PBKDF2_SHA256(passwd, passwdlen, salt, saltlen, 1, B, p * 128 * r);
+
+	/* 2: for i = 0 to p - 1 do */
+	for (i = 0; i < p; i++) {
+		/* 3: B_i <-- MF(B_i, N) */
+		smix(&B[i * 128 * r], r, N, V, XY);
+	}
+
+	/* 5: DK <-- PBKDF2(P, B, 1, dkLen) */
+	PBKDF2_SHA256(passwd, passwdlen, B, p * 128 * r, 1, buf, buflen);
+
+	/* Free memory. */
+#ifdef MAP_ANON
+	if (munmap(V0, 128 * r * N))
+		goto err2;
+#else
+	free(V0);
+#endif
+	free(XY0);
+	free(B0);
+
+	/* Success! */
+	return (0);
+
+err2:
+	free(XY0);
+err1:
+	free(B0);
+err0:
+	/* Failure! */
+	return (-1);
+}
diff --git a/cbits/crypto_scrypt.h b/cbits/crypto_scrypt.h
new file mode 100644
--- /dev/null
+++ b/cbits/crypto_scrypt.h
@@ -0,0 +1,46 @@
+/*-
+ * Copyright 2009 Colin Percival
+ * All rights reserved.
+ *
+ * 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, this list of conditions and the following disclaimer.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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 USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file was originally written by Colin Percival as part of the Tarsnap
+ * online backup system.
+ */
+#ifndef _CRYPTO_SCRYPT_H_
+#define _CRYPTO_SCRYPT_H_
+
+#include <stdint.h>
+#include <stddef.h>
+/**
+ * crypto_scrypt(passwd, passwdlen, salt, saltlen, N, r, p, buf, buflen):
+ * Compute scrypt(passwd[0 .. passwdlen - 1], salt[0 .. saltlen - 1], N, r,
+ * p, buflen) and write the result into buf.  The parameters r, p, and buflen
+ * must satisfy r * p < 2^30 and buflen <= (2^32 - 1) * 32.  The parameter N
+ * must be a power of 2 greater than 1.
+ *
+ * Return 0 on success; or -1 on error.
+ */
+int crypto_scrypt(const uint8_t *, size_t, const uint8_t *, size_t, uint64_t,
+    uint32_t, uint32_t, uint8_t *, size_t);
+
+#endif /* !_CRYPTO_SCRYPT_H_ */
diff --git a/cbits/sha256.c b/cbits/sha256.c
new file mode 100644
--- /dev/null
+++ b/cbits/sha256.c
@@ -0,0 +1,410 @@
+/*-
+ * Copyright 2005,2007,2009 Colin Percival
+ * All rights reserved.
+ *
+ * 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, this list of conditions and the following disclaimer.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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 USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#include <sys/types.h>
+
+#include <stdint.h>
+#include <string.h>
+
+#include "sysendian.h"
+
+#include "sha256.h"
+
+/*
+ * Encode a length len/4 vector of (uint32_t) into a length len vector of
+ * (unsigned char) in big-endian form.  Assumes len is a multiple of 4.
+ */
+static void
+be32enc_vect(unsigned char *dst, const uint32_t *src, size_t len)
+{
+	size_t i;
+
+	for (i = 0; i < len / 4; i++)
+		be32enc(dst + i * 4, src[i]);
+}
+
+/*
+ * Decode a big-endian length len vector of (unsigned char) into a length
+ * len/4 vector of (uint32_t).  Assumes len is a multiple of 4.
+ */
+static void
+be32dec_vect(uint32_t *dst, const unsigned char *src, size_t len)
+{
+	size_t i;
+
+	for (i = 0; i < len / 4; i++)
+		dst[i] = be32dec(src + i * 4);
+}
+
+/* Elementary functions used by SHA256 */
+#define Ch(x, y, z)	((x & (y ^ z)) ^ z)
+#define Maj(x, y, z)	((x & (y | z)) | (y & z))
+#define SHR(x, n)	(x >> n)
+#define ROTR(x, n)	((x >> n) | (x << (32 - n)))
+#define S0(x)		(ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
+#define S1(x)		(ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
+#define s0(x)		(ROTR(x, 7) ^ ROTR(x, 18) ^ SHR(x, 3))
+#define s1(x)		(ROTR(x, 17) ^ ROTR(x, 19) ^ SHR(x, 10))
+
+/* SHA256 round function */
+#define RND(a, b, c, d, e, f, g, h, k)			\
+	t0 = h + S1(e) + Ch(e, f, g) + k;		\
+	t1 = S0(a) + Maj(a, b, c);			\
+	d += t0;					\
+	h  = t0 + t1;
+
+/* Adjusted round function for rotating state */
+#define RNDr(S, W, i, k)			\
+	RND(S[(64 - i) % 8], S[(65 - i) % 8],	\
+	    S[(66 - i) % 8], S[(67 - i) % 8],	\
+	    S[(68 - i) % 8], S[(69 - i) % 8],	\
+	    S[(70 - i) % 8], S[(71 - i) % 8],	\
+	    W[i] + k)
+
+/*
+ * SHA256 block compression function.  The 256-bit state is transformed via
+ * the 512-bit input block to produce a new state.
+ */
+static void
+SHA256_Transform(uint32_t * state, const unsigned char block[64])
+{
+	uint32_t W[64];
+	uint32_t S[8];
+	uint32_t t0, t1;
+	int i;
+
+	/* 1. Prepare message schedule W. */
+	be32dec_vect(W, block, 64);
+	for (i = 16; i < 64; i++)
+		W[i] = s1(W[i - 2]) + W[i - 7] + s0(W[i - 15]) + W[i - 16];
+
+	/* 2. Initialize working variables. */
+	memcpy(S, state, 32);
+
+	/* 3. Mix. */
+	RNDr(S, W, 0, 0x428a2f98);
+	RNDr(S, W, 1, 0x71374491);
+	RNDr(S, W, 2, 0xb5c0fbcf);
+	RNDr(S, W, 3, 0xe9b5dba5);
+	RNDr(S, W, 4, 0x3956c25b);
+	RNDr(S, W, 5, 0x59f111f1);
+	RNDr(S, W, 6, 0x923f82a4);
+	RNDr(S, W, 7, 0xab1c5ed5);
+	RNDr(S, W, 8, 0xd807aa98);
+	RNDr(S, W, 9, 0x12835b01);
+	RNDr(S, W, 10, 0x243185be);
+	RNDr(S, W, 11, 0x550c7dc3);
+	RNDr(S, W, 12, 0x72be5d74);
+	RNDr(S, W, 13, 0x80deb1fe);
+	RNDr(S, W, 14, 0x9bdc06a7);
+	RNDr(S, W, 15, 0xc19bf174);
+	RNDr(S, W, 16, 0xe49b69c1);
+	RNDr(S, W, 17, 0xefbe4786);
+	RNDr(S, W, 18, 0x0fc19dc6);
+	RNDr(S, W, 19, 0x240ca1cc);
+	RNDr(S, W, 20, 0x2de92c6f);
+	RNDr(S, W, 21, 0x4a7484aa);
+	RNDr(S, W, 22, 0x5cb0a9dc);
+	RNDr(S, W, 23, 0x76f988da);
+	RNDr(S, W, 24, 0x983e5152);
+	RNDr(S, W, 25, 0xa831c66d);
+	RNDr(S, W, 26, 0xb00327c8);
+	RNDr(S, W, 27, 0xbf597fc7);
+	RNDr(S, W, 28, 0xc6e00bf3);
+	RNDr(S, W, 29, 0xd5a79147);
+	RNDr(S, W, 30, 0x06ca6351);
+	RNDr(S, W, 31, 0x14292967);
+	RNDr(S, W, 32, 0x27b70a85);
+	RNDr(S, W, 33, 0x2e1b2138);
+	RNDr(S, W, 34, 0x4d2c6dfc);
+	RNDr(S, W, 35, 0x53380d13);
+	RNDr(S, W, 36, 0x650a7354);
+	RNDr(S, W, 37, 0x766a0abb);
+	RNDr(S, W, 38, 0x81c2c92e);
+	RNDr(S, W, 39, 0x92722c85);
+	RNDr(S, W, 40, 0xa2bfe8a1);
+	RNDr(S, W, 41, 0xa81a664b);
+	RNDr(S, W, 42, 0xc24b8b70);
+	RNDr(S, W, 43, 0xc76c51a3);
+	RNDr(S, W, 44, 0xd192e819);
+	RNDr(S, W, 45, 0xd6990624);
+	RNDr(S, W, 46, 0xf40e3585);
+	RNDr(S, W, 47, 0x106aa070);
+	RNDr(S, W, 48, 0x19a4c116);
+	RNDr(S, W, 49, 0x1e376c08);
+	RNDr(S, W, 50, 0x2748774c);
+	RNDr(S, W, 51, 0x34b0bcb5);
+	RNDr(S, W, 52, 0x391c0cb3);
+	RNDr(S, W, 53, 0x4ed8aa4a);
+	RNDr(S, W, 54, 0x5b9cca4f);
+	RNDr(S, W, 55, 0x682e6ff3);
+	RNDr(S, W, 56, 0x748f82ee);
+	RNDr(S, W, 57, 0x78a5636f);
+	RNDr(S, W, 58, 0x84c87814);
+	RNDr(S, W, 59, 0x8cc70208);
+	RNDr(S, W, 60, 0x90befffa);
+	RNDr(S, W, 61, 0xa4506ceb);
+	RNDr(S, W, 62, 0xbef9a3f7);
+	RNDr(S, W, 63, 0xc67178f2);
+
+	/* 4. Mix local working variables into global state */
+	for (i = 0; i < 8; i++)
+		state[i] += S[i];
+
+	/* Clean the stack. */
+	memset(W, 0, 256);
+	memset(S, 0, 32);
+	t0 = t1 = 0;
+}
+
+static unsigned char PAD[64] = {
+	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+/* Add padding and terminating bit-count. */
+static void
+SHA256_Pad(SHA256_CTX * ctx)
+{
+	unsigned char len[8];
+	uint32_t r, plen;
+
+	/*
+	 * Convert length to a vector of bytes -- we do this now rather
+	 * than later because the length will change after we pad.
+	 */
+	be32enc_vect(len, ctx->count, 8);
+
+	/* Add 1--64 bytes so that the resulting length is 56 mod 64 */
+	r = (ctx->count[1] >> 3) & 0x3f;
+	plen = (r < 56) ? (56 - r) : (120 - r);
+	SHA256_Update(ctx, PAD, (size_t)plen);
+
+	/* Add the terminating bit-count */
+	SHA256_Update(ctx, len, 8);
+}
+
+/* SHA-256 initialization.  Begins a SHA-256 operation. */
+void
+SHA256_Init(SHA256_CTX * ctx)
+{
+
+	/* Zero bits processed so far */
+	ctx->count[0] = ctx->count[1] = 0;
+
+	/* Magic initialization constants */
+	ctx->state[0] = 0x6A09E667;
+	ctx->state[1] = 0xBB67AE85;
+	ctx->state[2] = 0x3C6EF372;
+	ctx->state[3] = 0xA54FF53A;
+	ctx->state[4] = 0x510E527F;
+	ctx->state[5] = 0x9B05688C;
+	ctx->state[6] = 0x1F83D9AB;
+	ctx->state[7] = 0x5BE0CD19;
+}
+
+/* Add bytes into the hash */
+void
+SHA256_Update(SHA256_CTX * ctx, const void *in, size_t len)
+{
+	uint32_t bitlen[2];
+	uint32_t r;
+	const unsigned char *src = in;
+
+	/* Number of bytes left in the buffer from previous updates */
+	r = (ctx->count[1] >> 3) & 0x3f;
+
+	/* Convert the length into a number of bits */
+	bitlen[1] = ((uint32_t)len) << 3;
+	bitlen[0] = (uint32_t)(len >> 29);
+
+	/* Update number of bits */
+	if ((ctx->count[1] += bitlen[1]) < bitlen[1])
+		ctx->count[0]++;
+	ctx->count[0] += bitlen[0];
+
+	/* Handle the case where we don't need to perform any transforms */
+	if (len < 64 - r) {
+		memcpy(&ctx->buf[r], src, len);
+		return;
+	}
+
+	/* Finish the current block */
+	memcpy(&ctx->buf[r], src, 64 - r);
+	SHA256_Transform(ctx->state, ctx->buf);
+	src += 64 - r;
+	len -= 64 - r;
+
+	/* Perform complete blocks */
+	while (len >= 64) {
+		SHA256_Transform(ctx->state, src);
+		src += 64;
+		len -= 64;
+	}
+
+	/* Copy left over data into buffer */
+	memcpy(ctx->buf, src, len);
+}
+
+/*
+ * SHA-256 finalization.  Pads the input data, exports the hash value,
+ * and clears the context state.
+ */
+void
+SHA256_Final(unsigned char digest[32], SHA256_CTX * ctx)
+{
+
+	/* Add padding */
+	SHA256_Pad(ctx);
+
+	/* Write the hash */
+	be32enc_vect(digest, ctx->state, 32);
+
+	/* Clear the context state */
+	memset((void *)ctx, 0, sizeof(*ctx));
+}
+
+/* Initialize an HMAC-SHA256 operation with the given key. */
+void
+HMAC_SHA256_Init(HMAC_SHA256_CTX * ctx, const void * _K, size_t Klen)
+{
+	unsigned char pad[64];
+	unsigned char khash[32];
+	const unsigned char * K = _K;
+	size_t i;
+
+	/* If Klen > 64, the key is really SHA256(K). */
+	if (Klen > 64) {
+		SHA256_Init(&ctx->ictx);
+		SHA256_Update(&ctx->ictx, K, Klen);
+		SHA256_Final(khash, &ctx->ictx);
+		K = khash;
+		Klen = 32;
+	}
+
+	/* Inner SHA256 operation is SHA256(K xor [block of 0x36] || data). */
+	SHA256_Init(&ctx->ictx);
+	memset(pad, 0x36, 64);
+	for (i = 0; i < Klen; i++)
+		pad[i] ^= K[i];
+	SHA256_Update(&ctx->ictx, pad, 64);
+
+	/* Outer SHA256 operation is SHA256(K xor [block of 0x5c] || hash). */
+	SHA256_Init(&ctx->octx);
+	memset(pad, 0x5c, 64);
+	for (i = 0; i < Klen; i++)
+		pad[i] ^= K[i];
+	SHA256_Update(&ctx->octx, pad, 64);
+
+	/* Clean the stack. */
+	memset(khash, 0, 32);
+}
+
+/* Add bytes to the HMAC-SHA256 operation. */
+void
+HMAC_SHA256_Update(HMAC_SHA256_CTX * ctx, const void *in, size_t len)
+{
+
+	/* Feed data to the inner SHA256 operation. */
+	SHA256_Update(&ctx->ictx, in, len);
+}
+
+/* Finish an HMAC-SHA256 operation. */
+void
+HMAC_SHA256_Final(unsigned char digest[32], HMAC_SHA256_CTX * ctx)
+{
+	unsigned char ihash[32];
+
+	/* Finish the inner SHA256 operation. */
+	SHA256_Final(ihash, &ctx->ictx);
+
+	/* Feed the inner hash to the outer SHA256 operation. */
+	SHA256_Update(&ctx->octx, ihash, 32);
+
+	/* Finish the outer SHA256 operation. */
+	SHA256_Final(digest, &ctx->octx);
+
+	/* Clean the stack. */
+	memset(ihash, 0, 32);
+}
+
+/**
+ * PBKDF2_SHA256(passwd, passwdlen, salt, saltlen, c, buf, dkLen):
+ * Compute PBKDF2(passwd, salt, c, dkLen) using HMAC-SHA256 as the PRF, and
+ * write the output to buf.  The value dkLen must be at most 32 * (2^32 - 1).
+ */
+void
+PBKDF2_SHA256(const uint8_t * passwd, size_t passwdlen, const uint8_t * salt,
+    size_t saltlen, uint64_t c, uint8_t * buf, size_t dkLen)
+{
+	HMAC_SHA256_CTX PShctx, hctx;
+	size_t i;
+	uint8_t ivec[4];
+	uint8_t U[32];
+	uint8_t T[32];
+	uint64_t j;
+	int k;
+	size_t clen;
+
+	/* Compute HMAC state after processing P and S. */
+	HMAC_SHA256_Init(&PShctx, passwd, passwdlen);
+	HMAC_SHA256_Update(&PShctx, salt, saltlen);
+
+	/* Iterate through the blocks. */
+	for (i = 0; i * 32 < dkLen; i++) {
+		/* Generate INT(i + 1). */
+		be32enc(ivec, (uint32_t)(i + 1));
+
+		/* Compute U_1 = PRF(P, S || INT(i)). */
+		memcpy(&hctx, &PShctx, sizeof(HMAC_SHA256_CTX));
+		HMAC_SHA256_Update(&hctx, ivec, 4);
+		HMAC_SHA256_Final(U, &hctx);
+
+		/* T_i = U_1 ... */
+		memcpy(T, U, 32);
+
+		for (j = 2; j <= c; j++) {
+			/* Compute U_j. */
+			HMAC_SHA256_Init(&hctx, passwd, passwdlen);
+			HMAC_SHA256_Update(&hctx, U, 32);
+			HMAC_SHA256_Final(U, &hctx);
+
+			/* ... xor U_j ... */
+			for (k = 0; k < 32; k++)
+				T[k] ^= U[k];
+		}
+
+		/* Copy as many bytes as necessary into buf. */
+		clen = dkLen - i * 32;
+		if (clen > 32)
+			clen = 32;
+		memcpy(&buf[i * 32], T, clen);
+	}
+
+	/* Clean PShctx, since we never called _Final on it. */
+	memset(&PShctx, 0, sizeof(HMAC_SHA256_CTX));
+}
diff --git a/cbits/sha256.h b/cbits/sha256.h
new file mode 100644
--- /dev/null
+++ b/cbits/sha256.h
@@ -0,0 +1,62 @@
+/*-
+ * Copyright 2005,2007,2009 Colin Percival
+ * All rights reserved.
+ *
+ * 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, this list of conditions and the following disclaimer.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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 USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD: src/lib/libmd/sha256.h,v 1.2 2006/01/17 15:35:56 phk Exp $
+ */
+
+#ifndef _SHA256_H_
+#define _SHA256_H_
+
+#include <sys/types.h>
+
+#include <stdint.h>
+
+typedef struct SHA256Context {
+	uint32_t state[8];
+	uint32_t count[2];
+	unsigned char buf[64];
+} SHA256_CTX;
+
+typedef struct HMAC_SHA256Context {
+	SHA256_CTX ictx;
+	SHA256_CTX octx;
+} HMAC_SHA256_CTX;
+
+void	SHA256_Init(SHA256_CTX *);
+void	SHA256_Update(SHA256_CTX *, const void *, size_t);
+void	SHA256_Final(unsigned char [32], SHA256_CTX *);
+void	HMAC_SHA256_Init(HMAC_SHA256_CTX *, const void *, size_t);
+void	HMAC_SHA256_Update(HMAC_SHA256_CTX *, const void *, size_t);
+void	HMAC_SHA256_Final(unsigned char [32], HMAC_SHA256_CTX *);
+
+/**
+ * PBKDF2_SHA256(passwd, passwdlen, salt, saltlen, c, buf, dkLen):
+ * Compute PBKDF2(passwd, salt, c, dkLen) using HMAC-SHA256 as the PRF, and
+ * write the output to buf.  The value dkLen must be at most 32 * (2^32 - 1).
+ */
+void	PBKDF2_SHA256(const uint8_t *, size_t, const uint8_t *, size_t,
+    uint64_t, uint8_t *, size_t);
+
+#endif /* !_SHA256_H_ */
diff --git a/cbits/sysendian.h b/cbits/sysendian.h
new file mode 100644
--- /dev/null
+++ b/cbits/sysendian.h
@@ -0,0 +1,138 @@
+/*-
+ * Copyright 2007-2009 Colin Percival
+ * All rights reserved.
+ *
+ * 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, this list of conditions and the following disclaimer.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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 USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file was originally written by Colin Percival as part of the Tarsnap
+ * online backup system.
+ */
+#ifndef _SYSENDIAN_H_
+#define _SYSENDIAN_H_
+
+/* If we don't have be64enc, the <sys/endian.h> we have isn't usable. */
+#if !HAVE_DECL_BE64ENC
+#undef HAVE_SYS_ENDIAN_H
+#endif
+
+#ifdef HAVE_SYS_ENDIAN_H
+
+#include <sys/endian.h>
+
+#else
+
+#include <stdint.h>
+
+static inline uint32_t
+be32dec(const void *pp)
+{
+	const uint8_t *p = (uint8_t const *)pp;
+
+	return ((uint32_t)(p[3]) + ((uint32_t)(p[2]) << 8) +
+	    ((uint32_t)(p[1]) << 16) + ((uint32_t)(p[0]) << 24));
+}
+
+static inline void
+be32enc(void *pp, uint32_t x)
+{
+	uint8_t * p = (uint8_t *)pp;
+
+	p[3] = x & 0xff;
+	p[2] = (x >> 8) & 0xff;
+	p[1] = (x >> 16) & 0xff;
+	p[0] = (x >> 24) & 0xff;
+}
+
+static inline uint64_t
+be64dec(const void *pp)
+{
+	const uint8_t *p = (uint8_t const *)pp;
+
+	return ((uint64_t)(p[7]) + ((uint64_t)(p[6]) << 8) +
+	    ((uint64_t)(p[5]) << 16) + ((uint64_t)(p[4]) << 24) +
+	    ((uint64_t)(p[3]) << 32) + ((uint64_t)(p[2]) << 40) +
+	    ((uint64_t)(p[1]) << 48) + ((uint64_t)(p[0]) << 56));
+}
+
+static inline void
+be64enc(void *pp, uint64_t x)
+{
+	uint8_t * p = (uint8_t *)pp;
+
+	p[7] = x & 0xff;
+	p[6] = (x >> 8) & 0xff;
+	p[5] = (x >> 16) & 0xff;
+	p[4] = (x >> 24) & 0xff;
+	p[3] = (x >> 32) & 0xff;
+	p[2] = (x >> 40) & 0xff;
+	p[1] = (x >> 48) & 0xff;
+	p[0] = (x >> 56) & 0xff;
+}
+
+static inline uint32_t
+le32dec(const void *pp)
+{
+	const uint8_t *p = (uint8_t const *)pp;
+
+	return ((uint32_t)(p[0]) + ((uint32_t)(p[1]) << 8) +
+	    ((uint32_t)(p[2]) << 16) + ((uint32_t)(p[3]) << 24));
+}
+
+static inline void
+le32enc(void *pp, uint32_t x)
+{
+	uint8_t * p = (uint8_t *)pp;
+
+	p[0] = x & 0xff;
+	p[1] = (x >> 8) & 0xff;
+	p[2] = (x >> 16) & 0xff;
+	p[3] = (x >> 24) & 0xff;
+}
+
+static inline uint64_t
+le64dec(const void *pp)
+{
+	const uint8_t *p = (uint8_t const *)pp;
+
+	return ((uint64_t)(p[0]) + ((uint64_t)(p[1]) << 8) +
+	    ((uint64_t)(p[2]) << 16) + ((uint64_t)(p[3]) << 24) +
+	    ((uint64_t)(p[4]) << 32) + ((uint64_t)(p[5]) << 40) +
+	    ((uint64_t)(p[6]) << 48) + ((uint64_t)(p[7]) << 56));
+}
+
+static inline void
+le64enc(void *pp, uint64_t x)
+{
+	uint8_t * p = (uint8_t *)pp;
+
+	p[0] = x & 0xff;
+	p[1] = (x >> 8) & 0xff;
+	p[2] = (x >> 16) & 0xff;
+	p[3] = (x >> 24) & 0xff;
+	p[4] = (x >> 32) & 0xff;
+	p[5] = (x >> 40) & 0xff;
+	p[6] = (x >> 48) & 0xff;
+	p[7] = (x >> 56) & 0xff;
+}
+#endif /* !HAVE_SYS_ENDIAN_H */
+
+#endif /* !_SYSENDIAN_H_ */
diff --git a/scrypt.cabal b/scrypt.cabal
new file mode 100644
--- /dev/null
+++ b/scrypt.cabal
@@ -0,0 +1,51 @@
+name:           scrypt
+version:        0.1
+license:        BSD3
+license-file:   LICENSE
+category:       Cryptography
+copyright:      Copyright 2011 Falko Peters
+author:         Falko Peters <falko.peters@gmail.com>
+maintainer:     Falko Peters <falko.peters@gmail.com>
+stability:      experimental
+tested-with:    GHC == 6.12.3
+cabal-version:  >= 1.8
+homepage:       http://github.com/informatikr/scrypt
+bug-reports:    http://github.com/informatikr/scrypt/issues
+build-type:     Simple
+synopsis:
+    Stronger password hashing via sequential memory-hard functions.
+description:
+    scrypt provides bindings to Colin Percival's `scrypt` 
+    implementation (<http://www.tarsnap.com/scrypt.html>). Scrypt is a key
+    derivation function designed to be far more secure against hardware
+    brute-force attacks than alternative functions such as PBKDF2 or bcrypt.
+    .
+    Details of the scrypt key derivation function are given in a paper by
+    Colin Percival, Stronger Key Derivation via Sequential Memory-Hard
+    Functions (<http://www.tarsnap.com/scrypt/scrypt-slides.pdf>).
+
+extra-source-files:
+    README.markdown,
+    cbits/crypto_scrypt.h,
+    cbits/sha256.h,
+    cbits/sysendian.h
+
+library
+    exposed-modules: Crypto.Scrypt
+
+    build-depends:
+        base == 4.*,
+        bytestring == 0.9.*
+
+    ghc-options: -Wall
+    ghc-prof-options: -auto-all
+
+    c-sources: cbits/crypto_scrypt-sse.c, cbits/sha256.c
+    cc-options: -msse2
+    include-dirs: cbits
+    includes: crypto_scrypt.h
+    install-includes: crypto_scrypt.h
+    
+source-repository head
+    type:     git
+    location: http://github.com/informatikr/scrypt
