camellia_glue.c

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/* Glue code for CAMELLIA encryption optimized for sparc64 crypto opcodes.
 *
 * Copyright (C) 2012 David S. Miller <[email protected]>
 */

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

#include "opcodes.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;
    u32 *flags = &tfm->crt_flags;

    if (key_len != 16 && key_len != 24 && key_len != 32) {
        *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
        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;
}

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;

#define CAMELLIA_BLOCK_MASK (~(CAMELLIA_BLOCK_SIZE - 1))

static int __ecb_crypt(struct blkcipher_desc *desc,
               struct scatterlist *dst, struct scatterlist *src,
               unsigned int nbytes, bool encrypt)
{
    struct camellia_sparc64_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
    struct blkcipher_walk walk;
    ecb_crypt_op *op;
    const u64 *key;
    int err;

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

    blkcipher_walk_init(&walk, dst, src, nbytes);
    err = blkcipher_walk_virt(desc, &walk);

    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)) {
        unsigned int block_len = nbytes & CAMELLIA_BLOCK_MASK;

        if (likely(block_len)) {
            const u64 *src64;
            u64 *dst64;

            src64 = (const u64 *)walk.src.virt.addr;
            dst64 = (u64 *) walk.dst.virt.addr;
            op(src64, dst64, block_len, key);
        }
        nbytes &= CAMELLIA_BLOCK_SIZE - 1;
        err = blkcipher_walk_done(desc, &walk, nbytes);
    }
    fprs_write(0);
    return err;
}

static int ecb_encrypt(struct blkcipher_desc *desc,
               struct scatterlist *dst, struct scatterlist *src,
               unsigned int nbytes)
{
    return __ecb_crypt(desc, dst, src, nbytes, true);
}

static int ecb_decrypt(struct blkcipher_desc *desc,
               struct scatterlist *dst, struct scatterlist *src,
               unsigned int nbytes)
{
    return __ecb_crypt(desc, dst, src, nbytes, 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 blkcipher_desc *desc,
               struct scatterlist *dst, struct scatterlist *src,
               unsigned int nbytes)
{
    struct camellia_sparc64_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
    struct blkcipher_walk walk;
    cbc_crypt_op *op;
    const u64 *key;
    int err;

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

    blkcipher_walk_init(&walk, dst, src, nbytes);
    err = blkcipher_walk_virt(desc, &walk);

    key = &ctx->encrypt_key[0];
    camellia_sparc64_load_keys(key, ctx->key_len);
    while ((nbytes = walk.nbytes)) {
        unsigned int block_len = nbytes & CAMELLIA_BLOCK_MASK;

        if (likely(block_len)) {
            const u64 *src64;
            u64 *dst64;

            src64 = (const u64 *)walk.src.virt.addr;
            dst64 = (u64 *) walk.dst.virt.addr;
            op(src64, dst64, block_len, key,
               (u64 *) walk.iv);
        }
        nbytes &= CAMELLIA_BLOCK_SIZE - 1;
        err = blkcipher_walk_done(desc, &walk, nbytes);
    }
    fprs_write(0);
    return err;
}

static int cbc_decrypt(struct blkcipher_desc *desc,
               struct scatterlist *dst, struct scatterlist *src,
               unsigned int nbytes)
{
    struct camellia_sparc64_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
    struct blkcipher_walk walk;
    cbc_crypt_op *op;
    const u64 *key;
    int err;

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

    blkcipher_walk_init(&walk, dst, src, nbytes);
    err = blkcipher_walk_virt(desc, &walk);

    key = &ctx->decrypt_key[0];
    camellia_sparc64_load_keys(key, ctx->key_len);
    while ((nbytes = walk.nbytes)) {
        unsigned int block_len = nbytes & CAMELLIA_BLOCK_MASK;

        if (likely(block_len)) {
            const u64 *src64;
            u64 *dst64;

            src64 = (const u64 *)walk.src.virt.addr;
            dst64 = (u64 *) walk.dst.virt.addr;
            op(src64, dst64, block_len, key,
               (u64 *) walk.iv);
        }
        nbytes &= CAMELLIA_BLOCK_SIZE - 1;
        err = blkcipher_walk_done(desc, &walk, nbytes);
    }
    fprs_write(0);
    return err;
}

static struct crypto_alg algs[] = { {
    .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
        }
    }
}, {
    .cra_name       = "ecb(camellia)",
    .cra_driver_name    = "ecb-camellia-sparc64",
    .cra_priority       = SPARC_CR_OPCODE_PRIORITY,
    .cra_flags      = CRYPTO_ALG_TYPE_BLKCIPHER,
    .cra_blocksize      = CAMELLIA_BLOCK_SIZE,
    .cra_ctxsize        = sizeof(struct camellia_sparc64_ctx),
    .cra_alignmask      = 7,
    .cra_type       = &crypto_blkcipher_type,
    .cra_module     = THIS_MODULE,
    .cra_u = {
        .blkcipher = {
            .min_keysize    = CAMELLIA_MIN_KEY_SIZE,
            .max_keysize    = CAMELLIA_MAX_KEY_SIZE,
            .setkey     = camellia_set_key,
            .encrypt    = ecb_encrypt,
            .decrypt    = ecb_decrypt,
        },
    },
}, {
    .cra_name       = "cbc(camellia)",
    .cra_driver_name    = "cbc-camellia-sparc64",
    .cra_priority       = SPARC_CR_OPCODE_PRIORITY,
    .cra_flags      = CRYPTO_ALG_TYPE_BLKCIPHER,
    .cra_blocksize      = CAMELLIA_BLOCK_SIZE,
    .cra_ctxsize        = sizeof(struct camellia_sparc64_ctx),
    .cra_alignmask      = 7,
    .cra_type       = &crypto_blkcipher_type,
    .cra_module     = THIS_MODULE,
    .cra_u = {
        .blkcipher = {
            .min_keysize    = CAMELLIA_MIN_KEY_SIZE,
            .max_keysize    = CAMELLIA_MAX_KEY_SIZE,
            .setkey     = camellia_set_key,
            .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 i;

    for (i = 0; i < ARRAY_SIZE(algs); i++)
        INIT_LIST_HEAD(&algs[i].cra_list);

    if (sparc64_has_camellia_opcode()) {
        pr_info("Using sparc64 camellia opcodes optimized CAMELLIA implementation\n");
        return crypto_register_algs(algs, ARRAY_SIZE(algs));
    }
    pr_info("sparc64 camellia opcodes not available.\n");
    return -ENODEV;
}

static void __exit camellia_sparc64_mod_fini(void)
{
    crypto_unregister_algs(algs, ARRAY_SIZE(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("aes");

#include "crop_devid.c"