1 files changed, 140 insertions, 0 deletions
diff --git a/crypto/sha1_generic.c b/crypto/sha1_generic.c
new file mode 100644
index 0000000..48a3c3e
--- /dev/null
+++ b/crypto/sha1_generic.c
@@ -0,0 +1,140 @@
+/*
+ * 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 <linux/types.h>
+#include <crypto/sha.h>
+#include <asm/scatterlist.h>
+#include <asm/byteorder.h>
+
+struct sha1_ctx {
+        u64 count;
+        u32 state[5];
+        u8 buffer[64];
+};
+
+static void sha1_init(struct crypto_tfm *tfm)
+{
+	struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
+	static const struct sha1_ctx initstate = {
+	  0,
+	  { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
+	  { 0, }
+	};
+
+	*sctx = initstate;
+}
+
+static void sha1_update(struct crypto_tfm *tfm, const u8 *data,
+			unsigned int len)
+{
+	struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
+	unsigned int partial, done;
+	const u8 *src;
+
+	partial = sctx->count & 0x3f;
+	sctx->count += len;
+	done = 0;
+	src = data;
+
+	if ((partial + len) > 63) {
+		u32 temp[SHA_WORKSPACE_WORDS];
+
+		if (partial) {
+			done = -partial;
+			memcpy(sctx->buffer + partial, data, done + 64);
+			src = sctx->buffer;
+		}
+
+		do {
+			sha_transform(sctx->state, src, temp);
+			done += 64;
+			src = data + done;
+		} while (done + 63 < len);
+
+		memset(temp, 0, sizeof(temp));
+		partial = 0;
+	}
+	memcpy(sctx->buffer + partial, src, len - done);
+}
+
+
+/* Add padding and return the message digest. */
+static void sha1_final(struct crypto_tfm *tfm, u8 *out)
+{
+	struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
+	__be32 *dst = (__be32 *)out;
+	u32 i, index, padlen;
+	__be64 bits;
+	static const u8 padding[64] = { 0x80, };
+
+	bits = cpu_to_be64(sctx->count << 3);
+
+	/* Pad out to 56 mod 64 */
+	index = sctx->count & 0x3f;
+	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
+	sha1_update(tfm, padding, padlen);
+
+	/* Append length */
+	sha1_update(tfm, (const u8 *)&bits, sizeof(bits));
+
+	/* Store state in digest */
+	for (i = 0; i < 5; i++)
+		dst[i] = cpu_to_be32(sctx->state[i]);
+
+	/* Wipe context */
+	memset(sctx, 0, sizeof *sctx);
+}
+
+static struct crypto_alg alg = {
+	.cra_name	=	"sha1",
+	.cra_driver_name=	"sha1-generic",
+	.cra_flags	=	CRYPTO_ALG_TYPE_DIGEST,
+	.cra_blocksize	=	SHA1_BLOCK_SIZE,
+	.cra_ctxsize	=	sizeof(struct sha1_ctx),
+	.cra_module	=	THIS_MODULE,
+	.cra_alignmask	=	3,
+	.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");
+
+MODULE_ALIAS("sha1");