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Diffstat (limited to '')
-rw-r--r-- | crypto/cipher.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/crypto/cipher.c b/crypto/cipher.c new file mode 100644 index 0000000000..47c77a3e59 --- /dev/null +++ b/crypto/cipher.c @@ -0,0 +1,120 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Cryptographic API. + * + * Single-block cipher operations. + * + * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> + * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au> + */ + +#include <crypto/algapi.h> +#include <crypto/internal/cipher.h> +#include <linux/kernel.h> +#include <linux/crypto.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/string.h> +#include "internal.h" + +static int setkey_unaligned(struct crypto_cipher *tfm, const u8 *key, + unsigned int keylen) +{ + struct cipher_alg *cia = crypto_cipher_alg(tfm); + unsigned long alignmask = crypto_cipher_alignmask(tfm); + int ret; + u8 *buffer, *alignbuffer; + unsigned long absize; + + absize = keylen + alignmask; + buffer = kmalloc(absize, GFP_ATOMIC); + if (!buffer) + return -ENOMEM; + + alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); + memcpy(alignbuffer, key, keylen); + ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen); + memset(alignbuffer, 0, keylen); + kfree(buffer); + return ret; + +} + +int crypto_cipher_setkey(struct crypto_cipher *tfm, + const u8 *key, unsigned int keylen) +{ + struct cipher_alg *cia = crypto_cipher_alg(tfm); + unsigned long alignmask = crypto_cipher_alignmask(tfm); + + if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize) + return -EINVAL; + + if ((unsigned long)key & alignmask) + return setkey_unaligned(tfm, key, keylen); + + return cia->cia_setkey(crypto_cipher_tfm(tfm), key, keylen); +} +EXPORT_SYMBOL_NS_GPL(crypto_cipher_setkey, CRYPTO_INTERNAL); + +static inline void cipher_crypt_one(struct crypto_cipher *tfm, + u8 *dst, const u8 *src, bool enc) +{ + unsigned long alignmask = crypto_cipher_alignmask(tfm); + struct cipher_alg *cia = crypto_cipher_alg(tfm); + void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = + enc ? cia->cia_encrypt : cia->cia_decrypt; + + if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) { + unsigned int bs = crypto_cipher_blocksize(tfm); + u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK]; + u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); + + memcpy(tmp, src, bs); + fn(crypto_cipher_tfm(tfm), tmp, tmp); + memcpy(dst, tmp, bs); + } else { + fn(crypto_cipher_tfm(tfm), dst, src); + } +} + +void crypto_cipher_encrypt_one(struct crypto_cipher *tfm, + u8 *dst, const u8 *src) +{ + cipher_crypt_one(tfm, dst, src, true); +} +EXPORT_SYMBOL_NS_GPL(crypto_cipher_encrypt_one, CRYPTO_INTERNAL); + +void crypto_cipher_decrypt_one(struct crypto_cipher *tfm, + u8 *dst, const u8 *src) +{ + cipher_crypt_one(tfm, dst, src, false); +} +EXPORT_SYMBOL_NS_GPL(crypto_cipher_decrypt_one, CRYPTO_INTERNAL); + +struct crypto_cipher *crypto_clone_cipher(struct crypto_cipher *cipher) +{ + struct crypto_tfm *tfm = crypto_cipher_tfm(cipher); + struct crypto_alg *alg = tfm->__crt_alg; + struct crypto_cipher *ncipher; + struct crypto_tfm *ntfm; + + if (alg->cra_init) + return ERR_PTR(-ENOSYS); + + if (unlikely(!crypto_mod_get(alg))) + return ERR_PTR(-ESTALE); + + ntfm = __crypto_alloc_tfmgfp(alg, CRYPTO_ALG_TYPE_CIPHER, + CRYPTO_ALG_TYPE_MASK, GFP_ATOMIC); + if (IS_ERR(ntfm)) { + crypto_mod_put(alg); + return ERR_CAST(ntfm); + } + + ntfm->crt_flags = tfm->crt_flags; + + ncipher = __crypto_cipher_cast(ntfm); + + return ncipher; +} +EXPORT_SYMBOL_GPL(crypto_clone_cipher); |