CRYPTO: Octeon: Add SHA256 module

Add OCTEON SHA256 module.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David S. Miller <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9493/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 281 insertions, 0 deletions

diff --git a/arch/mips/cavium-octeon/crypto/Makefile b/arch/mips/cavium-octeon/crypto/Makefile
index 3f671d60a3d9..47806a5c5d71 100644
--- a/arch/mips/cavium-octeon/crypto/Makefile
+++ b/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
diff --git a/arch/mips/cavium-octeon/crypto/octeon-sha256.c b/arch/mips/cavium-octeon/crypto/octeon-sha256.c
new file mode 100644
index 000000000000..97e96fead08a
--- /dev/null
+++ b/arch/mips/cavium-octeon/crypto/octeon-sha256.c
@@ -0,0 +1,280 @@
+/*
+ * 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>");