linux/include/crypto/internal/des.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * DES & Triple DES EDE key verification helpers
 */

#ifndef __CRYPTO_INTERNAL_DES_H
#define __CRYPTO_INTERNAL_DES_H

#include <linux/crypto.h>
#include <linux/fips.h>
#include <crypto/des.h>
#include <crypto/aead.h>
#include <crypto/skcipher.h>

/**
 * crypto_des_verify_key - Check whether a DES key is weak
 * @tfm: the crypto algo
 * @key: the key buffer
 *
 * Returns -EINVAL if the key is weak and the crypto TFM does not permit weak
 * keys. Otherwise, 0 is returned.
 *
 * It is the job of the caller to ensure that the size of the key equals
 * DES_KEY_SIZE.
 */
static inline int crypto_des_verify_key(struct crypto_tfm *tfm, const u8 *key)
{ … }

/*
 * RFC2451:
 *
 *   For DES-EDE3, there is no known need to reject weak or
 *   complementation keys.  Any weakness is obviated by the use of
 *   multiple keys.
 *
 *   However, if the first two or last two independent 64-bit keys are
 *   equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
 *   same as DES.  Implementers MUST reject keys that exhibit this
 *   property.
 *
 */
static inline int des3_ede_verify_key(const u8 *key, unsigned int key_len,
				      bool check_weak)
{ … }

/**
 * crypto_des3_ede_verify_key - Check whether a DES3-EDE key is weak
 * @tfm: the crypto algo
 * @key: the key buffer
 *
 * Returns -EINVAL if the key is weak and the crypto TFM does not permit weak
 * keys or when running in FIPS mode. Otherwise, 0 is returned. Note that some
 * keys are rejected in FIPS mode even if weak keys are permitted by the TFM
 * flags.
 *
 * It is the job of the caller to ensure that the size of the key equals
 * DES3_EDE_KEY_SIZE.
 */
static inline int crypto_des3_ede_verify_key(struct crypto_tfm *tfm,
					     const u8 *key)
{ … }

static inline int verify_skcipher_des_key(struct crypto_skcipher *tfm,
					  const u8 *key)
{ … }

static inline int verify_skcipher_des3_key(struct crypto_skcipher *tfm,
					   const u8 *key)
{ … }

static inline int verify_aead_des_key(struct crypto_aead *tfm, const u8 *key,
				      int keylen)
{ … }

static inline int verify_aead_des3_key(struct crypto_aead *tfm, const u8 *key,
				       int keylen)
{ … }

#endif /* __CRYPTO_INTERNAL_DES_H */