diff --git a/crypto/sha1.c b/crypto/sha1.c
new file mode 100644
index 0000000..4016f3b
--- /dev/null
+++ b/crypto/sha1.c
@@ -0,0 +1,139 @@
+/*
+ * Cryptographic API.
+ *
+ * SHA1 Secure Hash Algorithm.
+ *
+ * Derived from cryptoapi implementation, adapted for in-place
+ * scatterlist interface.
+ *
+ * Copyright (c) Alan Smithee.
+ * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
+ * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/crypto.h>
+#include <linux/cryptohash.h>
+#include <asm/scatterlist.h>
+#include <asm/byteorder.h>
+
+#define SHA1_DIGEST_SIZE	20
+#define SHA1_HMAC_BLOCK_SIZE	64
+
+struct sha1_ctx {
+        u64 count;
+        u32 state[5];
+        u8 buffer[64];
+};
+
+static void sha1_init(void *ctx)
+{
+	struct sha1_ctx *sctx = ctx;
+	static const struct sha1_ctx initstate = {
+	  0,
+	  { 0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476, 0xC3D2E1F0 },
+	  { 0, }
+	};
+
+	*sctx = initstate;
+}
+
+static void sha1_update(void *ctx, const u8 *data, unsigned int len)
+{
+	struct sha1_ctx *sctx = ctx;
+	unsigned int i, j;
+	u32 temp[SHA_WORKSPACE_WORDS];
+
+	j = (sctx->count >> 3) & 0x3f;
+	sctx->count += len << 3;
+
+	if ((j + len) > 63) {
+		memcpy(&sctx->buffer[j], data, (i = 64-j));
+		sha_transform(sctx->state, sctx->buffer, temp);
+		for ( ; i + 63 < len; i += 64) {
+			sha_transform(sctx->state, &data[i], temp);
+		}
+		j = 0;
+	}
+	else i = 0;
+	memset(temp, 0, sizeof(temp));
+	memcpy(&sctx->buffer[j], &data[i], len - i);
+}
+
+
+/* Add padding and return the message digest. */
+static void sha1_final(void* ctx, u8 *out)
+{
+	struct sha1_ctx *sctx = ctx;
+	u32 i, j, index, padlen;
+	u64 t;
+	u8 bits[8] = { 0, };
+	static const u8 padding[64] = { 0x80, };
+
+	t = sctx->count;
+	bits[7] = 0xff & t; t>>=8;
+	bits[6] = 0xff & t; t>>=8;
+	bits[5] = 0xff & t; t>>=8;
+	bits[4] = 0xff & t; t>>=8;
+	bits[3] = 0xff & t; t>>=8;
+	bits[2] = 0xff & t; t>>=8;
+	bits[1] = 0xff & t; t>>=8;
+	bits[0] = 0xff & t;
+
+	/* Pad out to 56 mod 64 */
+	index = (sctx->count >> 3) & 0x3f;
+	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
+	sha1_update(sctx, padding, padlen);
+
+	/* Append length */
+	sha1_update(sctx, bits, sizeof bits); 
+
+	/* Store state in digest */
+	for (i = j = 0; i < 5; i++, j += 4) {
+		u32 t2 = sctx->state[i];
+		out[j+3] = t2 & 0xff; t2>>=8;
+		out[j+2] = t2 & 0xff; t2>>=8;
+		out[j+1] = t2 & 0xff; t2>>=8;
+		out[j  ] = t2 & 0xff;
+	}
+
+	/* Wipe context */
+	memset(sctx, 0, sizeof *sctx);
+}
+
+static struct crypto_alg alg = {
+	.cra_name	=	"sha1",
+	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
+	.cra_blocksize	=	SHA1_HMAC_BLOCK_SIZE,
+	.cra_ctxsize	=	sizeof(struct sha1_ctx),
+	.cra_module	=	THIS_MODULE,
+	.cra_list       =       LIST_HEAD_INIT(alg.cra_list),
+	.cra_u		=	{ .digest = {
+	.dia_digestsize	=	SHA1_DIGEST_SIZE,
+	.dia_init   	= 	sha1_init,
+	.dia_update 	=	sha1_update,
+	.dia_final  	=	sha1_final } }
+};
+
+static int __init init(void)
+{
+	return crypto_register_alg(&alg);
+}
+
+static void __exit fini(void)
+{
+	crypto_unregister_alg(&alg);
+}
+
+module_init(init);
+module_exit(fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");