root/crypto/hash.c

DEFINITIONS

1. crypto_hash_ctxsize
2. hash_setkey_unaligned
3. hash_setkey
4. hash_async_setkey
5. hash_async_init
6. hash_async_update
7. hash_async_final
8. hash_async_digest
9. crypto_init_hash_ops_async
10. crypto_init_hash_ops_sync
11. crypto_init_hash_ops
12. crypto_hash_show

/*
 * Cryptographic Hash operations.
 * 
 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * 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 <crypto/internal/hash.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/seq_file.h>

#include "internal.h"

static unsigned int crypto_hash_ctxsize(struct crypto_alg *alg, u32 type,
                                        u32 mask)
{
        return alg->cra_ctxsize;
}

static int hash_setkey_unaligned(struct crypto_hash *crt, const u8 *key,
                                 unsigned int keylen)
{
        struct crypto_tfm *tfm = crypto_hash_tfm(crt);
        struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
        unsigned long alignmask = crypto_hash_alignmask(crt);
        int ret;
        u8 *buffer, *alignbuffer;
        unsigned long absize;

        absize = keylen + alignmask;
        buffer = kmalloc(absize, GFP_ATOMIC);
        if (!buffer)
                return -ENOMEM;

        alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
        memcpy(alignbuffer, key, keylen);
        ret = alg->setkey(crt, alignbuffer, keylen);
        memset(alignbuffer, 0, keylen);
        kfree(buffer);
        return ret;
}

static int hash_setkey(struct crypto_hash *crt, const u8 *key,
                       unsigned int keylen)
{
        struct crypto_tfm *tfm = crypto_hash_tfm(crt);
        struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
        unsigned long alignmask = crypto_hash_alignmask(crt);

        if ((unsigned long)key & alignmask)
                return hash_setkey_unaligned(crt, key, keylen);

        return alg->setkey(crt, key, keylen);
}

static int hash_async_setkey(struct crypto_ahash *tfm_async, const u8 *key,
                        unsigned int keylen)
{
        struct crypto_tfm  *tfm      = crypto_ahash_tfm(tfm_async);
        struct crypto_hash *tfm_hash = __crypto_hash_cast(tfm);
        struct hash_alg    *alg      = &tfm->__crt_alg->cra_hash;

        return alg->setkey(tfm_hash, key, keylen);
}

static int hash_async_init(struct ahash_request *req)
{
        struct crypto_tfm *tfm = req->base.tfm;
        struct hash_alg   *alg = &tfm->__crt_alg->cra_hash;
        struct hash_desc  desc = {
                .tfm = __crypto_hash_cast(tfm),
                .flags = req->base.flags,
        };

        return alg->init(&desc);
}

static int hash_async_update(struct ahash_request *req)
{
        struct crypto_tfm *tfm = req->base.tfm;
        struct hash_alg   *alg = &tfm->__crt_alg->cra_hash;
        struct hash_desc  desc = {
                .tfm = __crypto_hash_cast(tfm),
                .flags = req->base.flags,
        };

        return alg->update(&desc, req->src, req->nbytes);
}

static int hash_async_final(struct ahash_request *req)
{
        struct crypto_tfm *tfm = req->base.tfm;
        struct hash_alg   *alg = &tfm->__crt_alg->cra_hash;
        struct hash_desc  desc = {
                .tfm = __crypto_hash_cast(tfm),
                .flags = req->base.flags,
        };

        return alg->final(&desc, req->result);
}

static int hash_async_digest(struct ahash_request *req)
{
        struct crypto_tfm *tfm = req->base.tfm;
        struct hash_alg   *alg = &tfm->__crt_alg->cra_hash;
        struct hash_desc  desc = {
                .tfm = __crypto_hash_cast(tfm),
                .flags = req->base.flags,
        };

        return alg->digest(&desc, req->src, req->nbytes, req->result);
}

static int crypto_init_hash_ops_async(struct crypto_tfm *tfm)
{
        struct ahash_tfm *crt = &tfm->crt_ahash;
        struct hash_alg  *alg = &tfm->__crt_alg->cra_hash;

        crt->init       = hash_async_init;
        crt->update     = hash_async_update;
        crt->final      = hash_async_final;
        crt->digest     = hash_async_digest;
        crt->setkey     = hash_async_setkey;
        crt->digestsize = alg->digestsize;

        return 0;
}

static int crypto_init_hash_ops_sync(struct crypto_tfm *tfm)
{
        struct hash_tfm *crt = &tfm->crt_hash;
        struct hash_alg *alg = &tfm->__crt_alg->cra_hash;

        crt->init       = alg->init;
        crt->update     = alg->update;
        crt->final      = alg->final;
        crt->digest     = alg->digest;
        crt->setkey     = hash_setkey;
        crt->digestsize = alg->digestsize;

        return 0;
}

static int crypto_init_hash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
{
        struct hash_alg *alg = &tfm->__crt_alg->cra_hash;

        if (alg->digestsize > PAGE_SIZE / 8)
                return -EINVAL;

        if ((mask & CRYPTO_ALG_TYPE_HASH_MASK) != CRYPTO_ALG_TYPE_HASH_MASK)
                return crypto_init_hash_ops_async(tfm);
        else
                return crypto_init_hash_ops_sync(tfm);
}

static void crypto_hash_show(struct seq_file *m, struct crypto_alg *alg)
        __attribute__ ((unused));
static void crypto_hash_show(struct seq_file *m, struct crypto_alg *alg)
{
        seq_printf(m, "type         : hash\n");
        seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
        seq_printf(m, "digestsize   : %u\n", alg->cra_hash.digestsize);
}

const struct crypto_type crypto_hash_type = {
        .ctxsize = crypto_hash_ctxsize,
        .init = crypto_init_hash_ops,
#ifdef CONFIG_PROC_FS
        .show = crypto_hash_show,
#endif
};
EXPORT_SYMBOL_GPL(crypto_hash_type);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Generic cryptographic hash type");