root/arch/sparc/crypto/camellia_glue.c
// SPDX-License-Identifier: GPL-2.0-only
/* Glue code for CAMELLIA encryption optimized for sparc64 crypto opcodes.
 *
 * Copyright (C) 2012 David S. Miller <davem@davemloft.net>
 */

#define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt

#include <linux/crypto.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <crypto/algapi.h>
#include <crypto/internal/skcipher.h>

#include <asm/fpumacro.h>
#include <asm/opcodes.h>
#include <asm/pstate.h>
#include <asm/elf.h>

#define CAMELLIA_MIN_KEY_SIZE        16
#define CAMELLIA_MAX_KEY_SIZE        32
#define CAMELLIA_BLOCK_SIZE          16
#define CAMELLIA_TABLE_BYTE_LEN     272

struct camellia_sparc64_ctx {
        u64 encrypt_key[CAMELLIA_TABLE_BYTE_LEN / sizeof(u64)];
        u64 decrypt_key[CAMELLIA_TABLE_BYTE_LEN / sizeof(u64)];
        int key_len;
};

extern void camellia_sparc64_key_expand(const u32 *in_key, u64 *encrypt_key,
                                        unsigned int key_len, u64 *decrypt_key);

static int camellia_set_key(struct crypto_tfm *tfm, const u8 *_in_key,
                            unsigned int key_len)
{
        struct camellia_sparc64_ctx *ctx = crypto_tfm_ctx(tfm);
        const u32 *in_key = (const u32 *) _in_key;

        if (key_len != 16 && key_len != 24 && key_len != 32)
                return -EINVAL;

        ctx->key_len = key_len;

        camellia_sparc64_key_expand(in_key, &ctx->encrypt_key[0],
                                    key_len, &ctx->decrypt_key[0]);
        return 0;
}

static int camellia_set_key_skcipher(struct crypto_skcipher *tfm,
                                     const u8 *in_key, unsigned int key_len)
{
        return camellia_set_key(crypto_skcipher_tfm(tfm), in_key, key_len);
}

extern void camellia_sparc64_crypt(const u64 *key, const u32 *input,
                                   u32 *output, unsigned int key_len);

static void camellia_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
        struct camellia_sparc64_ctx *ctx = crypto_tfm_ctx(tfm);

        camellia_sparc64_crypt(&ctx->encrypt_key[0],
                               (const u32 *) src,
                               (u32 *) dst, ctx->key_len);
}

static void camellia_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
        struct camellia_sparc64_ctx *ctx = crypto_tfm_ctx(tfm);

        camellia_sparc64_crypt(&ctx->decrypt_key[0],
                               (const u32 *) src,
                               (u32 *) dst, ctx->key_len);
}

extern void camellia_sparc64_load_keys(const u64 *key, unsigned int key_len);

typedef void ecb_crypt_op(const u64 *input, u64 *output, unsigned int len,
                          const u64 *key);

extern ecb_crypt_op camellia_sparc64_ecb_crypt_3_grand_rounds;
extern ecb_crypt_op camellia_sparc64_ecb_crypt_4_grand_rounds;

static int __ecb_crypt(struct skcipher_request *req, bool encrypt)
{
        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
        const struct camellia_sparc64_ctx *ctx = crypto_skcipher_ctx(tfm);
        struct skcipher_walk walk;
        ecb_crypt_op *op;
        const u64 *key;
        unsigned int nbytes;
        int err;

        op = camellia_sparc64_ecb_crypt_3_grand_rounds;
        if (ctx->key_len != 16)
                op = camellia_sparc64_ecb_crypt_4_grand_rounds;

        err = skcipher_walk_virt(&walk, req, true);
        if (err)
                return err;

        if (encrypt)
                key = &ctx->encrypt_key[0];
        else
                key = &ctx->decrypt_key[0];
        camellia_sparc64_load_keys(key, ctx->key_len);
        while ((nbytes = walk.nbytes) != 0) {
                op(walk.src.virt.addr, walk.dst.virt.addr,
                   round_down(nbytes, CAMELLIA_BLOCK_SIZE), key);
                err = skcipher_walk_done(&walk, nbytes % CAMELLIA_BLOCK_SIZE);
        }
        fprs_write(0);
        return err;
}

static int ecb_encrypt(struct skcipher_request *req)
{
        return __ecb_crypt(req, true);
}

static int ecb_decrypt(struct skcipher_request *req)
{
        return __ecb_crypt(req, false);
}

typedef void cbc_crypt_op(const u64 *input, u64 *output, unsigned int len,
                          const u64 *key, u64 *iv);

extern cbc_crypt_op camellia_sparc64_cbc_encrypt_3_grand_rounds;
extern cbc_crypt_op camellia_sparc64_cbc_encrypt_4_grand_rounds;
extern cbc_crypt_op camellia_sparc64_cbc_decrypt_3_grand_rounds;
extern cbc_crypt_op camellia_sparc64_cbc_decrypt_4_grand_rounds;

static int cbc_encrypt(struct skcipher_request *req)
{
        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
        const struct camellia_sparc64_ctx *ctx = crypto_skcipher_ctx(tfm);
        struct skcipher_walk walk;
        cbc_crypt_op *op;
        const u64 *key;
        unsigned int nbytes;
        int err;

        op = camellia_sparc64_cbc_encrypt_3_grand_rounds;
        if (ctx->key_len != 16)
                op = camellia_sparc64_cbc_encrypt_4_grand_rounds;

        err = skcipher_walk_virt(&walk, req, true);
        if (err)
                return err;

        key = &ctx->encrypt_key[0];
        camellia_sparc64_load_keys(key, ctx->key_len);
        while ((nbytes = walk.nbytes) != 0) {
                op(walk.src.virt.addr, walk.dst.virt.addr,
                   round_down(nbytes, CAMELLIA_BLOCK_SIZE), key, walk.iv);
                err = skcipher_walk_done(&walk, nbytes % CAMELLIA_BLOCK_SIZE);
        }
        fprs_write(0);
        return err;
}

static int cbc_decrypt(struct skcipher_request *req)
{
        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
        const struct camellia_sparc64_ctx *ctx = crypto_skcipher_ctx(tfm);
        struct skcipher_walk walk;
        cbc_crypt_op *op;
        const u64 *key;
        unsigned int nbytes;
        int err;

        op = camellia_sparc64_cbc_decrypt_3_grand_rounds;
        if (ctx->key_len != 16)
                op = camellia_sparc64_cbc_decrypt_4_grand_rounds;

        err = skcipher_walk_virt(&walk, req, true);
        if (err)
                return err;

        key = &ctx->decrypt_key[0];
        camellia_sparc64_load_keys(key, ctx->key_len);
        while ((nbytes = walk.nbytes) != 0) {
                op(walk.src.virt.addr, walk.dst.virt.addr,
                   round_down(nbytes, CAMELLIA_BLOCK_SIZE), key, walk.iv);
                err = skcipher_walk_done(&walk, nbytes % CAMELLIA_BLOCK_SIZE);
        }
        fprs_write(0);
        return err;
}

static struct crypto_alg cipher_alg = {
        .cra_name               = "camellia",
        .cra_driver_name        = "camellia-sparc64",
        .cra_priority           = SPARC_CR_OPCODE_PRIORITY,
        .cra_flags              = CRYPTO_ALG_TYPE_CIPHER,
        .cra_blocksize          = CAMELLIA_BLOCK_SIZE,
        .cra_ctxsize            = sizeof(struct camellia_sparc64_ctx),
        .cra_alignmask          = 3,
        .cra_module             = THIS_MODULE,
        .cra_u  = {
                .cipher = {
                        .cia_min_keysize        = CAMELLIA_MIN_KEY_SIZE,
                        .cia_max_keysize        = CAMELLIA_MAX_KEY_SIZE,
                        .cia_setkey             = camellia_set_key,
                        .cia_encrypt            = camellia_encrypt,
                        .cia_decrypt            = camellia_decrypt
                }
        }
};

static struct skcipher_alg skcipher_algs[] = {
        {
                .base.cra_name          = "ecb(camellia)",
                .base.cra_driver_name   = "ecb-camellia-sparc64",
                .base.cra_priority      = SPARC_CR_OPCODE_PRIORITY,
                .base.cra_blocksize     = CAMELLIA_BLOCK_SIZE,
                .base.cra_ctxsize       = sizeof(struct camellia_sparc64_ctx),
                .base.cra_alignmask     = 7,
                .base.cra_module        = THIS_MODULE,
                .min_keysize            = CAMELLIA_MIN_KEY_SIZE,
                .max_keysize            = CAMELLIA_MAX_KEY_SIZE,
                .setkey                 = camellia_set_key_skcipher,
                .encrypt                = ecb_encrypt,
                .decrypt                = ecb_decrypt,
        }, {
                .base.cra_name          = "cbc(camellia)",
                .base.cra_driver_name   = "cbc-camellia-sparc64",
                .base.cra_priority      = SPARC_CR_OPCODE_PRIORITY,
                .base.cra_blocksize     = CAMELLIA_BLOCK_SIZE,
                .base.cra_ctxsize       = sizeof(struct camellia_sparc64_ctx),
                .base.cra_alignmask     = 7,
                .base.cra_module        = THIS_MODULE,
                .min_keysize            = CAMELLIA_MIN_KEY_SIZE,
                .max_keysize            = CAMELLIA_MAX_KEY_SIZE,
                .ivsize                 = CAMELLIA_BLOCK_SIZE,
                .setkey                 = camellia_set_key_skcipher,
                .encrypt                = cbc_encrypt,
                .decrypt                = cbc_decrypt,
        }
};

static bool __init sparc64_has_camellia_opcode(void)
{
        unsigned long cfr;

        if (!(sparc64_elf_hwcap & HWCAP_SPARC_CRYPTO))
                return false;

        __asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
        if (!(cfr & CFR_CAMELLIA))
                return false;

        return true;
}

static int __init camellia_sparc64_mod_init(void)
{
        int err;

        if (!sparc64_has_camellia_opcode()) {
                pr_info("sparc64 camellia opcodes not available.\n");
                return -ENODEV;
        }
        pr_info("Using sparc64 camellia opcodes optimized CAMELLIA implementation\n");
        err = crypto_register_alg(&cipher_alg);
        if (err)
                return err;
        err = crypto_register_skciphers(skcipher_algs,
                                        ARRAY_SIZE(skcipher_algs));
        if (err)
                crypto_unregister_alg(&cipher_alg);
        return err;
}

static void __exit camellia_sparc64_mod_fini(void)
{
        crypto_unregister_alg(&cipher_alg);
        crypto_unregister_skciphers(skcipher_algs, ARRAY_SIZE(skcipher_algs));
}

module_init(camellia_sparc64_mod_init);
module_exit(camellia_sparc64_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Camellia Cipher Algorithm, sparc64 camellia opcode accelerated");

MODULE_ALIAS_CRYPTO("camellia");

#include "crop_devid.c"