crypto: octeon - add SHA256 module

Add OCTEON SHA256 module.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

arch/mips/cavium-octeon/crypto/Makefile

@@ -6,3 +6,4 @@ obj-y += octeon-crypto.o
 
 obj-$(CONFIG_CRYPTO_MD5_OCTEON)		+= octeon-md5.o
 obj-$(CONFIG_CRYPTO_SHA1_OCTEON)	+= octeon-sha1.o
+obj-$(CONFIG_CRYPTO_SHA256_OCTEON)	+= octeon-sha256.o

arch/mips/cavium-octeon/crypto/octeon-sha256.c

+/*
+ * Cryptographic API.
+ *
+ * SHA-224 and SHA-256 Secure Hash Algorithm.
+ *
+ * Adapted for OCTEON by Aaro Koskinen <aaro.koskinen@iki.fi>.
+ *
+ * Based on crypto/sha256_generic.c, which is:
+ *
+ * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
+ * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ * SHA224 Support Copyright 2007 Intel Corporation <jonathan.lynch@intel.com>
+ *
+ * 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/mm.h>
+#include <crypto/sha.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <asm/byteorder.h>
+#include <asm/octeon/octeon.h>
+#include <crypto/internal/hash.h>
+
+#include "octeon-crypto.h"
+
+/*
+ * We pass everything as 64-bit. OCTEON can handle misaligned data.
+ */
+
+static void octeon_sha256_store_hash(struct sha256_state *sctx)
+{
+	u64 *hash = (u64 *)sctx->state;
+
+	write_octeon_64bit_hash_dword(hash[0], 0);
+	write_octeon_64bit_hash_dword(hash[1], 1);
+	write_octeon_64bit_hash_dword(hash[2], 2);
+	write_octeon_64bit_hash_dword(hash[3], 3);
+}
+
+static void octeon_sha256_read_hash(struct sha256_state *sctx)
+{
+	u64 *hash = (u64 *)sctx->state;
+
+	hash[0] = read_octeon_64bit_hash_dword(0);
+	hash[1] = read_octeon_64bit_hash_dword(1);
+	hash[2] = read_octeon_64bit_hash_dword(2);
+	hash[3] = read_octeon_64bit_hash_dword(3);
+}
+
+static void octeon_sha256_transform(const void *_block)
+{
+	const u64 *block = _block;
+
+	write_octeon_64bit_block_dword(block[0], 0);
+	write_octeon_64bit_block_dword(block[1], 1);
+	write_octeon_64bit_block_dword(block[2], 2);
+	write_octeon_64bit_block_dword(block[3], 3);
+	write_octeon_64bit_block_dword(block[4], 4);
+	write_octeon_64bit_block_dword(block[5], 5);
+	write_octeon_64bit_block_dword(block[6], 6);
+	octeon_sha256_start(block[7]);
+}
+
+static int octeon_sha224_init(struct shash_desc *desc)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+
+	sctx->state[0] = SHA224_H0;
+	sctx->state[1] = SHA224_H1;
+	sctx->state[2] = SHA224_H2;
+	sctx->state[3] = SHA224_H3;
+	sctx->state[4] = SHA224_H4;
+	sctx->state[5] = SHA224_H5;
+	sctx->state[6] = SHA224_H6;
+	sctx->state[7] = SHA224_H7;
+	sctx->count = 0;
+
+	return 0;
+}
+
+static int octeon_sha256_init(struct shash_desc *desc)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+
+	sctx->state[0] = SHA256_H0;
+	sctx->state[1] = SHA256_H1;
+	sctx->state[2] = SHA256_H2;
+	sctx->state[3] = SHA256_H3;
+	sctx->state[4] = SHA256_H4;
+	sctx->state[5] = SHA256_H5;
+	sctx->state[6] = SHA256_H6;
+	sctx->state[7] = SHA256_H7;
+	sctx->count = 0;
+
+	return 0;
+}
+
+static void __octeon_sha256_update(struct sha256_state *sctx, const u8 *data,
+				   unsigned int len)
+{
+	unsigned int partial;
+	unsigned int done;
+	const u8 *src;
+
+	partial = sctx->count % SHA256_BLOCK_SIZE;
+	sctx->count += len;
+	done = 0;
+	src = data;
+
+	if ((partial + len) >= SHA256_BLOCK_SIZE) {
+		if (partial) {
+			done = -partial;
+			memcpy(sctx->buf + partial, data,
+			       done + SHA256_BLOCK_SIZE);
+			src = sctx->buf;
+		}
+
+		do {
+			octeon_sha256_transform(src);
+			done += SHA256_BLOCK_SIZE;
+			src = data + done;
+		} while (done + SHA256_BLOCK_SIZE <= len);
+
+		partial = 0;
+	}
+	memcpy(sctx->buf + partial, src, len - done);
+}
+
+static int octeon_sha256_update(struct shash_desc *desc, const u8 *data,
+				unsigned int len)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+	struct octeon_cop2_state state;
+	unsigned long flags;
+
+	/*
+	 * Small updates never reach the crypto engine, so the generic sha256 is
+	 * faster because of the heavyweight octeon_crypto_enable() /
+	 * octeon_crypto_disable().
+	 */
+	if ((sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
+		return crypto_sha256_update(desc, data, len);
+
+	flags = octeon_crypto_enable(&state);
+	octeon_sha256_store_hash(sctx);
+
+	__octeon_sha256_update(sctx, data, len);
+
+	octeon_sha256_read_hash(sctx);
+	octeon_crypto_disable(&state, flags);
+
+	return 0;
+}
+
+static int octeon_sha256_final(struct shash_desc *desc, u8 *out)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+	static const u8 padding[64] = { 0x80, };
+	struct octeon_cop2_state state;
+	__be32 *dst = (__be32 *)out;
+	unsigned int pad_len;
+	unsigned long flags;
+	unsigned int index;
+	__be64 bits;
+	int i;
+
+	/* Save number of bits. */
+	bits = cpu_to_be64(sctx->count << 3);
+
+	/* Pad out to 56 mod 64. */
+	index = sctx->count & 0x3f;
+	pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
+
+	flags = octeon_crypto_enable(&state);
+	octeon_sha256_store_hash(sctx);
+
+	__octeon_sha256_update(sctx, padding, pad_len);
+
+	/* Append length (before padding). */
+	__octeon_sha256_update(sctx, (const u8 *)&bits, sizeof(bits));
+
+	octeon_sha256_read_hash(sctx);
+	octeon_crypto_disable(&state, flags);
+
+	/* Store state in digest */
+	for (i = 0; i < 8; i++)
+		dst[i] = cpu_to_be32(sctx->state[i]);
+
+	/* Zeroize sensitive information. */
+	memset(sctx, 0, sizeof(*sctx));
+
+	return 0;
+}
+
+static int octeon_sha224_final(struct shash_desc *desc, u8 *hash)
+{
+	u8 D[SHA256_DIGEST_SIZE];
+
+	octeon_sha256_final(desc, D);
+
+	memcpy(hash, D, SHA224_DIGEST_SIZE);
+	memzero_explicit(D, SHA256_DIGEST_SIZE);
+
+	return 0;
+}
+
+static int octeon_sha256_export(struct shash_desc *desc, void *out)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+
+	memcpy(out, sctx, sizeof(*sctx));
+	return 0;
+}
+
+static int octeon_sha256_import(struct shash_desc *desc, const void *in)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+
+	memcpy(sctx, in, sizeof(*sctx));
+	return 0;
+}
+
+static struct shash_alg octeon_sha256_algs[2] = { {
+	.digestsize	=	SHA256_DIGEST_SIZE,
+	.init		=	octeon_sha256_init,
+	.update		=	octeon_sha256_update,
+	.final		=	octeon_sha256_final,
+	.export		=	octeon_sha256_export,
+	.import		=	octeon_sha256_import,
+	.descsize	=	sizeof(struct sha256_state),
+	.statesize	=	sizeof(struct sha256_state),
+	.base		=	{
+		.cra_name	=	"sha256",
+		.cra_driver_name=	"octeon-sha256",
+		.cra_priority	=	OCTEON_CR_OPCODE_PRIORITY,
+		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize	=	SHA256_BLOCK_SIZE,
+		.cra_module	=	THIS_MODULE,
+	}
+}, {
+	.digestsize	=	SHA224_DIGEST_SIZE,
+	.init		=	octeon_sha224_init,
+	.update		=	octeon_sha256_update,
+	.final		=	octeon_sha224_final,
+	.descsize	=	sizeof(struct sha256_state),
+	.base		=	{
+		.cra_name	=	"sha224",
+		.cra_driver_name=	"octeon-sha224",
+		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize	=	SHA224_BLOCK_SIZE,
+		.cra_module	=	THIS_MODULE,
+	}
+} };
+
+static int __init octeon_sha256_mod_init(void)
+{
+	if (!octeon_has_crypto())
+		return -ENOTSUPP;
+	return crypto_register_shashes(octeon_sha256_algs,
+				       ARRAY_SIZE(octeon_sha256_algs));
+}
+
+static void __exit octeon_sha256_mod_fini(void)
+{
+	crypto_unregister_shashes(octeon_sha256_algs,
+				  ARRAY_SIZE(octeon_sha256_algs));
+}
+
+module_init(octeon_sha256_mod_init);
+module_exit(octeon_sha256_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SHA-224 and SHA-256 Secure Hash Algorithm (OCTEON)");
+MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");