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/* * Cryptographic API. * * Cipher operations. * * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> * Copyright (c) 2005 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 <linux/kernel.h>#include <linux/crypto.h>#include <linux/errno.h>#include <linux/scatterlist.h>#include <linux/string.h>#include "internal.h" static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen){	struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;		tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;	if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize) {		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;		return -EINVAL;	} else		return cia->cia_setkey(tfm, key, keylen);} static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *,					      const u8 *),				   struct crypto_tfm *tfm,				   u8 *dst, const u8 *src){	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);	unsigned int size = crypto_tfm_alg_blocksize(tfm);	u8 buffer[size + alignmask];	u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); 	memcpy(tmp, src, size);	fn(tfm, tmp, tmp);	memcpy(dst, tmp, size);} static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,				     u8 *dst, const u8 *src){	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher; 	if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {		cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);		return;	} 	cipher->cia_encrypt(tfm, dst, src);} static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,				     u8 *dst, const u8 *src){	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher; 	if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {		cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);		return;	} 	cipher->cia_decrypt(tfm, dst, src);} int crypto_init_cipher_ops(struct crypto_tfm *tfm){	struct cipher_tfm *ops = &tfm->crt_cipher;	struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher; 	ops->cit_setkey = setkey;	ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?		cipher_encrypt_unaligned : cipher->cia_encrypt;	ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?		cipher_decrypt_unaligned : cipher->cia_decrypt; 	return 0;} void crypto_exit_cipher_ops(struct crypto_tfm *tfm){}