rtl_crypto.h

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/*
 * Scatterlist Cryptographic API.
 *
 * Copyright (c) 2002 James Morris <[email protected]>
 * Copyright (c) 2002 David S. Miller ([email protected])
 *
 * Portions derived from Cryptoapi, by Alexander Kjeldaas <[email protected]>
 * and Nettle, by Niels M鰈ler.
 *
 * 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.
 *
 */
#ifndef _LINUX_CRYPTO_H
#define _LINUX_CRYPTO_H

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/string.h>
#include <asm/page.h>
#include <linux/errno.h>

#define crypto_register_alg crypto_register_alg_rsl
#define crypto_unregister_alg crypto_unregister_alg_rsl
#define crypto_alloc_tfm crypto_alloc_tfm_rsl
#define crypto_free_tfm crypto_free_tfm_rsl
#define crypto_alg_available crypto_alg_available_rsl

/*
 * Algorithm masks and types.
 */
#define CRYPTO_ALG_TYPE_MASK        0x000000ff
#define CRYPTO_ALG_TYPE_CIPHER      0x00000001
#define CRYPTO_ALG_TYPE_DIGEST      0x00000002
#define CRYPTO_ALG_TYPE_COMPRESS    0x00000004

/*
 * Transform masks and values (for crt_flags).
 */
#define CRYPTO_TFM_MODE_MASK        0x000000ff
#define CRYPTO_TFM_REQ_MASK     0x000fff00
#define CRYPTO_TFM_RES_MASK     0xfff00000

#define CRYPTO_TFM_MODE_ECB     0x00000001
#define CRYPTO_TFM_MODE_CBC     0x00000002
#define CRYPTO_TFM_MODE_CFB     0x00000004
#define CRYPTO_TFM_MODE_CTR     0x00000008

#define CRYPTO_TFM_REQ_WEAK_KEY     0x00000100
#define CRYPTO_TFM_RES_WEAK_KEY     0x00100000
#define CRYPTO_TFM_RES_BAD_KEY_LEN  0x00200000
#define CRYPTO_TFM_RES_BAD_KEY_SCHED    0x00400000
#define CRYPTO_TFM_RES_BAD_BLOCK_LEN    0x00800000
#define CRYPTO_TFM_RES_BAD_FLAGS    0x01000000

/*
 * Miscellaneous stuff.
 */
#define CRYPTO_UNSPEC           0
#define CRYPTO_MAX_ALG_NAME     64

struct scatterlist;

/*
 * Algorithms: modular crypto algorithm implementations, managed
 * via crypto_register_alg() and crypto_unregister_alg().
 */
struct cipher_alg {
    unsigned int cia_min_keysize;
    unsigned int cia_max_keysize;
    int (*cia_setkey)(void *ctx, const u8 *key,
              unsigned int keylen, u32 *flags);
    void (*cia_encrypt)(void *ctx, u8 *dst, const u8 *src);
    void (*cia_decrypt)(void *ctx, u8 *dst, const u8 *src);
};

struct digest_alg {
    unsigned int dia_digestsize;
    void (*dia_init)(void *ctx);
    void (*dia_update)(void *ctx, const u8 *data, unsigned int len);
    void (*dia_final)(void *ctx, u8 *out);
    int (*dia_setkey)(void *ctx, const u8 *key,
              unsigned int keylen, u32 *flags);
};

struct compress_alg {
    int (*coa_init)(void *ctx);
    void (*coa_exit)(void *ctx);
    int (*coa_compress)(void *ctx, const u8 *src, unsigned int slen,
                u8 *dst, unsigned int *dlen);
    int (*coa_decompress)(void *ctx, const u8 *src, unsigned int slen,
                  u8 *dst, unsigned int *dlen);
};

#define cra_cipher  cra_u.cipher
#define cra_digest  cra_u.digest
#define cra_compress    cra_u.compress

struct crypto_alg {
    struct list_head cra_list;
    u32 cra_flags;
    unsigned int cra_blocksize;
    unsigned int cra_ctxsize;
    const char cra_name[CRYPTO_MAX_ALG_NAME];

    union {
        struct cipher_alg cipher;
        struct digest_alg digest;
        struct compress_alg compress;
    } cra_u;

    struct module *cra_module;
};

/*
 * Algorithm registration interface.
 */
int crypto_register_alg(struct crypto_alg *alg);
int crypto_unregister_alg(struct crypto_alg *alg);

/*
 * Algorithm query interface.
 */
int crypto_alg_available(const char *name, u32 flags);

/*
 * Transforms: user-instantiated objects which encapsulate algorithms
 * and core processing logic.  Managed via crypto_alloc_tfm() and
 * crypto_free_tfm(), as well as the various helpers below.
 */
struct crypto_tfm;

struct cipher_tfm {
    void *cit_iv;
    unsigned int cit_ivsize;
    u32 cit_mode;
    int (*cit_setkey)(struct crypto_tfm *tfm,
              const u8 *key, unsigned int keylen);
    int (*cit_encrypt)(struct crypto_tfm *tfm,
               struct scatterlist *dst,
               struct scatterlist *src,
               unsigned int nbytes);
    int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
                  struct scatterlist *dst,
                  struct scatterlist *src,
                  unsigned int nbytes, u8 *iv);
    int (*cit_decrypt)(struct crypto_tfm *tfm,
               struct scatterlist *dst,
               struct scatterlist *src,
               unsigned int nbytes);
    int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
               struct scatterlist *dst,
               struct scatterlist *src,
               unsigned int nbytes, u8 *iv);
    void (*cit_xor_block)(u8 *dst, const u8 *src);
};

struct digest_tfm {
    void (*dit_init)(struct crypto_tfm *tfm);
    void (*dit_update)(struct crypto_tfm *tfm,
               struct scatterlist *sg, unsigned int nsg);
    void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
    void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
               unsigned int nsg, u8 *out);
    int (*dit_setkey)(struct crypto_tfm *tfm,
              const u8 *key, unsigned int keylen);
};

struct compress_tfm {
    int (*cot_compress)(struct crypto_tfm *tfm,
                const u8 *src, unsigned int slen,
                u8 *dst, unsigned int *dlen);
    int (*cot_decompress)(struct crypto_tfm *tfm,
                  const u8 *src, unsigned int slen,
                  u8 *dst, unsigned int *dlen);
};

#define crt_cipher  crt_u.cipher
#define crt_digest  crt_u.digest
#define crt_compress    crt_u.compress

struct crypto_tfm {

    u32 crt_flags;

    union {
        struct cipher_tfm cipher;
        struct digest_tfm digest;
        struct compress_tfm compress;
    } crt_u;

    struct crypto_alg *__crt_alg;
};

/*
 * Transform user interface.
 */

/*
 * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 * If that fails and the kernel supports dynamically loadable modules, it
 * will then attempt to load a module of the same name or alias.  A refcount
 * is grabbed on the algorithm which is then associated with the new transform.
 *
 * crypto_free_tfm() frees up the transform and any associated resources,
 * then drops the refcount on the associated algorithm.
 */
struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
void crypto_free_tfm(struct crypto_tfm *tfm);

/*
 * Transform helpers which query the underlying algorithm.
 */
static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
{
    return tfm->__crt_alg->cra_name;
}

static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
{
    struct crypto_alg *alg = tfm->__crt_alg;

    if (alg->cra_module)
        return alg->cra_module->name;
    else
        return NULL;
}

static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
{
    return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
}

static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    return tfm->__crt_alg->cra_cipher.cia_min_keysize;
}

static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    return tfm->__crt_alg->cra_cipher.cia_max_keysize;
}

static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    return tfm->crt_cipher.cit_ivsize;
}

static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
{
    return tfm->__crt_alg->cra_blocksize;
}

static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
    return tfm->__crt_alg->cra_digest.dia_digestsize;
}

/*
 * API wrappers.
 */
static inline void crypto_digest_init(struct crypto_tfm *tfm)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
    tfm->crt_digest.dit_init(tfm);
}

static inline void crypto_digest_update(struct crypto_tfm *tfm,
                    struct scatterlist *sg,
                    unsigned int nsg)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
    tfm->crt_digest.dit_update(tfm, sg, nsg);
}

static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
    tfm->crt_digest.dit_final(tfm, out);
}

static inline void crypto_digest_digest(struct crypto_tfm *tfm,
                    struct scatterlist *sg,
                    unsigned int nsg, u8 *out)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
    tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
}

static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
                       const u8 *key, unsigned int keylen)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
    if (tfm->crt_digest.dit_setkey == NULL)
        return -ENOSYS;
    return tfm->crt_digest.dit_setkey(tfm, key, keylen);
}

static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
                       const u8 *key, unsigned int keylen)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
}

static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
                    struct scatterlist *dst,
                    struct scatterlist *src,
                    unsigned int nbytes)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
}

static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
                       struct scatterlist *dst,
                       struct scatterlist *src,
                       unsigned int nbytes, u8 *iv)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
    return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
}

static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
                    struct scatterlist *dst,
                    struct scatterlist *src,
                    unsigned int nbytes)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
}

static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
                       struct scatterlist *dst,
                       struct scatterlist *src,
                       unsigned int nbytes, u8 *iv)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
    return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
}

static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
                    const u8 *src, unsigned int len)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    memcpy(tfm->crt_cipher.cit_iv, src, len);
}

static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
                    u8 *dst, unsigned int len)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
    memcpy(dst, tfm->crt_cipher.cit_iv, len);
}

static inline int crypto_comp_compress(struct crypto_tfm *tfm,
                       const u8 *src, unsigned int slen,
                       u8 *dst, unsigned int *dlen)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
    return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
}

static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
                     const u8 *src, unsigned int slen,
                     u8 *dst, unsigned int *dlen)
{
    BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
    return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
}

#endif  /* _LINUX_CRYPTO_H */