md5_glue.c

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/* Glue code for MD5 hashing optimized for sparc64 crypto opcodes.
 *
 * This is based largely upon arch/x86/crypto/sha1_ssse3_glue.c
 * and crypto/md5.c which are:
 *
 * Copyright (c) Alan Smithee.
 * Copyright (c) Andrew McDonald <[email protected]>
 * Copyright (c) Jean-Francois Dive <[email protected]>
 * Copyright (c) Mathias Krause <[email protected]>
 * Copyright (c) Cryptoapi developers.
 * Copyright (c) 2002 James Morris <[email protected]>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/cryptohash.h>
#include <linux/types.h>
#include <crypto/md5.h>

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

#include "opcodes.h"

asmlinkage void md5_sparc64_transform(u32 *digest, const char *data,
                      unsigned int rounds);

static int md5_sparc64_init(struct shash_desc *desc)
{
    struct md5_state *mctx = shash_desc_ctx(desc);

    mctx->hash[0] = cpu_to_le32(0x67452301);
    mctx->hash[1] = cpu_to_le32(0xefcdab89);
    mctx->hash[2] = cpu_to_le32(0x98badcfe);
    mctx->hash[3] = cpu_to_le32(0x10325476);
    mctx->byte_count = 0;

    return 0;
}

static void __md5_sparc64_update(struct md5_state *sctx, const u8 *data,
                 unsigned int len, unsigned int partial)
{
    unsigned int done = 0;

    sctx->byte_count += len;
    if (partial) {
        done = MD5_HMAC_BLOCK_SIZE - partial;
        memcpy((u8 *)sctx->block + partial, data, done);
        md5_sparc64_transform(sctx->hash, (u8 *)sctx->block, 1);
    }
    if (len - done >= MD5_HMAC_BLOCK_SIZE) {
        const unsigned int rounds = (len - done) / MD5_HMAC_BLOCK_SIZE;

        md5_sparc64_transform(sctx->hash, data + done, rounds);
        done += rounds * MD5_HMAC_BLOCK_SIZE;
    }

    memcpy(sctx->block, data + done, len - done);
}

static int md5_sparc64_update(struct shash_desc *desc, const u8 *data,
                  unsigned int len)
{
    struct md5_state *sctx = shash_desc_ctx(desc);
    unsigned int partial = sctx->byte_count % MD5_HMAC_BLOCK_SIZE;

    /* Handle the fast case right here */
    if (partial + len < MD5_HMAC_BLOCK_SIZE) {
        sctx->byte_count += len;
        memcpy((u8 *)sctx->block + partial, data, len);
    } else
        __md5_sparc64_update(sctx, data, len, partial);

    return 0;
}

/* Add padding and return the message digest. */
static int md5_sparc64_final(struct shash_desc *desc, u8 *out)
{
    struct md5_state *sctx = shash_desc_ctx(desc);
    unsigned int i, index, padlen;
    u32 *dst = (u32 *)out;
    __le64 bits;
    static const u8 padding[MD5_HMAC_BLOCK_SIZE] = { 0x80, };

    bits = cpu_to_le64(sctx->byte_count << 3);

    /* Pad out to 56 mod 64 and append length */
    index = sctx->byte_count % MD5_HMAC_BLOCK_SIZE;
    padlen = (index < 56) ? (56 - index) : ((MD5_HMAC_BLOCK_SIZE+56) - index);

    /* We need to fill a whole block for __md5_sparc64_update() */
    if (padlen <= 56) {
        sctx->byte_count += padlen;
        memcpy((u8 *)sctx->block + index, padding, padlen);
    } else {
        __md5_sparc64_update(sctx, padding, padlen, index);
    }
    __md5_sparc64_update(sctx, (const u8 *)&bits, sizeof(bits), 56);

    /* Store state in digest */
    for (i = 0; i < MD5_HASH_WORDS; i++)
        dst[i] = sctx->hash[i];

    /* Wipe context */
    memset(sctx, 0, sizeof(*sctx));

    return 0;
}

static int md5_sparc64_export(struct shash_desc *desc, void *out)
{
    struct md5_state *sctx = shash_desc_ctx(desc);

    memcpy(out, sctx, sizeof(*sctx));

    return 0;
}

static int md5_sparc64_import(struct shash_desc *desc, const void *in)
{
    struct md5_state *sctx = shash_desc_ctx(desc);

    memcpy(sctx, in, sizeof(*sctx));

    return 0;
}

static struct shash_alg alg = {
    .digestsize =   MD5_DIGEST_SIZE,
    .init       =   md5_sparc64_init,
    .update     =   md5_sparc64_update,
    .final      =   md5_sparc64_final,
    .export     =   md5_sparc64_export,
    .import     =   md5_sparc64_import,
    .descsize   =   sizeof(struct md5_state),
    .statesize  =   sizeof(struct md5_state),
    .base       =   {
        .cra_name   =   "md5",
        .cra_driver_name=   "md5-sparc64",
        .cra_priority   =   SPARC_CR_OPCODE_PRIORITY,
        .cra_flags  =   CRYPTO_ALG_TYPE_SHASH,
        .cra_blocksize  =   MD5_HMAC_BLOCK_SIZE,
        .cra_module =   THIS_MODULE,
    }
};

static bool __init sparc64_has_md5_opcode(void)
{
    unsigned long cfr;

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

    __asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
    if (!(cfr & CFR_MD5))
        return false;

    return true;
}

static int __init md5_sparc64_mod_init(void)
{
    if (sparc64_has_md5_opcode()) {
        pr_info("Using sparc64 md5 opcode optimized MD5 implementation\n");
        return crypto_register_shash(&alg);
    }
    pr_info("sparc64 md5 opcode not available.\n");
    return -ENODEV;
}

static void __exit md5_sparc64_mod_fini(void)
{
    crypto_unregister_shash(&alg);
}

module_init(md5_sparc64_mod_init);
module_exit(md5_sparc64_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MD5 Secure Hash Algorithm, sparc64 md5 opcode accelerated");

MODULE_ALIAS("md5");

#include "crop_devid.c"