linux-imx

/*

 * Cryptographic API.

 *

 * HMAC: Keyed-Hashing for Message Authentication (RFC2104).

 *

 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>

 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>

 *

 * The HMAC implementation is derived from USAGI.

 * Copyright (c) 2002 Kazunori Miyazawa <miyazawa@linux-ipv6.org> / USAGI

 *

 * 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/hmac.h>

#include <crypto/internal/hash.h>

#include <crypto/scatterwalk.h>

#include <linux/err.h>

#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/scatterlist.h>

#include <linux/string.h>

​

struct hmac_ctx {

    struct crypto_shash *hash;

};

​

static inline void *align_ptr(void *p, unsigned int align)

{

    return (void *)ALIGN((unsigned long)p, align);

}

​

static inline struct hmac_ctx *hmac_ctx(struct crypto_shash *tfm)

{

    return align_ptr(crypto_shash_ctx_aligned(tfm) +

             crypto_shash_statesize(tfm) * 2,

             crypto_tfm_ctx_alignment());

}

​

static int hmac_setkey(struct crypto_shash *parent,

               const u8 *inkey, unsigned int keylen)

{

    int bs = crypto_shash_blocksize(parent);

    int ds = crypto_shash_digestsize(parent);

    int ss = crypto_shash_statesize(parent);

    char *ipad = crypto_shash_ctx_aligned(parent);

    char *opad = ipad + ss;

    struct hmac_ctx *ctx = align_ptr(opad + ss,

                     crypto_tfm_ctx_alignment());

    struct crypto_shash *hash = ctx->hash;

    SHASH_DESC_ON_STACK(shash, hash);

    unsigned int i;

​

    shash->tfm = hash;

    shash->flags = crypto_shash_get_flags(parent)

        & CRYPTO_TFM_REQ_MAY_SLEEP;

​

    if (keylen > bs) {