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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Cryptographic API.4 *5 * Single-block cipher operations.6 *7 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>8 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>9 */10 11#include <crypto/algapi.h>12#include <crypto/internal/cipher.h>13#include <linux/kernel.h>14#include <linux/crypto.h>15#include <linux/errno.h>16#include <linux/slab.h>17#include <linux/string.h>18#include "internal.h"19 20static int setkey_unaligned(struct crypto_cipher *tfm, const u8 *key,21 unsigned int keylen)22{23 struct cipher_alg *cia = crypto_cipher_alg(tfm);24 unsigned long alignmask = crypto_cipher_alignmask(tfm);25 int ret;26 u8 *buffer, *alignbuffer;27 unsigned long absize;28 29 absize = keylen + alignmask;30 buffer = kmalloc(absize, GFP_ATOMIC);31 if (!buffer)32 return -ENOMEM;33 34 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);35 memcpy(alignbuffer, key, keylen);36 ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen);37 kfree_sensitive(buffer);38 return ret;39 40}41 42int crypto_cipher_setkey(struct crypto_cipher *tfm,43 const u8 *key, unsigned int keylen)44{45 struct cipher_alg *cia = crypto_cipher_alg(tfm);46 unsigned long alignmask = crypto_cipher_alignmask(tfm);47 48 if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize)49 return -EINVAL;50 51 if ((unsigned long)key & alignmask)52 return setkey_unaligned(tfm, key, keylen);53 54 return cia->cia_setkey(crypto_cipher_tfm(tfm), key, keylen);55}56EXPORT_SYMBOL_NS_GPL(crypto_cipher_setkey, CRYPTO_INTERNAL);57 58static inline void cipher_crypt_one(struct crypto_cipher *tfm,59 u8 *dst, const u8 *src, bool enc)60{61 unsigned long alignmask = crypto_cipher_alignmask(tfm);62 struct cipher_alg *cia = crypto_cipher_alg(tfm);63 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =64 enc ? cia->cia_encrypt : cia->cia_decrypt;65 66 if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {67 unsigned int bs = crypto_cipher_blocksize(tfm);68 u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];69 u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);70 71 memcpy(tmp, src, bs);72 fn(crypto_cipher_tfm(tfm), tmp, tmp);73 memcpy(dst, tmp, bs);74 } else {75 fn(crypto_cipher_tfm(tfm), dst, src);76 }77}78 79void crypto_cipher_encrypt_one(struct crypto_cipher *tfm,80 u8 *dst, const u8 *src)81{82 cipher_crypt_one(tfm, dst, src, true);83}84EXPORT_SYMBOL_NS_GPL(crypto_cipher_encrypt_one, CRYPTO_INTERNAL);85 86void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,87 u8 *dst, const u8 *src)88{89 cipher_crypt_one(tfm, dst, src, false);90}91EXPORT_SYMBOL_NS_GPL(crypto_cipher_decrypt_one, CRYPTO_INTERNAL);92 93struct crypto_cipher *crypto_clone_cipher(struct crypto_cipher *cipher)94{95 struct crypto_tfm *tfm = crypto_cipher_tfm(cipher);96 struct crypto_alg *alg = tfm->__crt_alg;97 struct crypto_cipher *ncipher;98 struct crypto_tfm *ntfm;99 100 if (alg->cra_init)101 return ERR_PTR(-ENOSYS);102 103 if (unlikely(!crypto_mod_get(alg)))104 return ERR_PTR(-ESTALE);105 106 ntfm = __crypto_alloc_tfmgfp(alg, CRYPTO_ALG_TYPE_CIPHER,107 CRYPTO_ALG_TYPE_MASK, GFP_ATOMIC);108 if (IS_ERR(ntfm)) {109 crypto_mod_put(alg);110 return ERR_CAST(ntfm);111 }112 113 ntfm->crt_flags = tfm->crt_flags;114 115 ncipher = __crypto_cipher_cast(ntfm);116 117 return ncipher;118}119EXPORT_SYMBOL_GPL(crypto_clone_cipher);120