[CRYPTO] cipher: Added encrypt_one/decrypt_one

This patch adds two new operations for the simple cipher that encrypts or
decrypts a single block at a time.  This will be the main interface after
the existing block operations have moved over to the new block ciphers.

It also adds the crypto_cipher type which is currently only used on the
new operations but will be extended to setkey as well once existing users
have been converted to use block ciphers where applicable.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 48 insertions, 0 deletions

diff --git a/crypto/cipher.c b/crypto/cipher.c
index f573c59ed9d..d8ca0ec8d0b 100644
--- a/crypto/cipher.c
+++ b/crypto/cipher.c
@@ -388,12 +388,60 @@ int crypto_init_cipher_flags(struct crypto_tfm *tfm, u32 flags)
 	return 0;
 }
 
+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)
 {
 	int ret = 0;
 	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;
 
 	switch (tfm->crt_cipher.cit_mode) {
 	case CRYPTO_TFM_MODE_ECB: