96 lines · c
1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Common values for AES algorithms4 */5 6#ifndef _CRYPTO_AES_H7#define _CRYPTO_AES_H8 9#include <linux/types.h>10#include <linux/crypto.h>11 12#define AES_MIN_KEY_SIZE 1613#define AES_MAX_KEY_SIZE 3214#define AES_KEYSIZE_128 1615#define AES_KEYSIZE_192 2416#define AES_KEYSIZE_256 3217#define AES_BLOCK_SIZE 1618#define AES_MAX_KEYLENGTH (15 * 16)19#define AES_MAX_KEYLENGTH_U32 (AES_MAX_KEYLENGTH / sizeof(u32))20 21/*22 * Please ensure that the first two fields are 16-byte aligned23 * relative to the start of the structure, i.e., don't move them!24 */25struct crypto_aes_ctx {26 u32 key_enc[AES_MAX_KEYLENGTH_U32];27 u32 key_dec[AES_MAX_KEYLENGTH_U32];28 u32 key_length;29};30 31extern const u32 crypto_ft_tab[4][256] ____cacheline_aligned;32extern const u32 crypto_it_tab[4][256] ____cacheline_aligned;33 34/*35 * validate key length for AES algorithms36 */37static inline int aes_check_keylen(unsigned int keylen)38{39 switch (keylen) {40 case AES_KEYSIZE_128:41 case AES_KEYSIZE_192:42 case AES_KEYSIZE_256:43 break;44 default:45 return -EINVAL;46 }47 48 return 0;49}50 51int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,52 unsigned int key_len);53 54/**55 * aes_expandkey - Expands the AES key as described in FIPS-19756 * @ctx: The location where the computed key will be stored.57 * @in_key: The supplied key.58 * @key_len: The length of the supplied key.59 *60 * Returns 0 on success. The function fails only if an invalid key size (or61 * pointer) is supplied.62 * The expanded key size is 240 bytes (max of 14 rounds with a unique 16 bytes63 * key schedule plus a 16 bytes key which is used before the first round).64 * The decryption key is prepared for the "Equivalent Inverse Cipher" as65 * described in FIPS-197. The first slot (16 bytes) of each key (enc or dec) is66 * for the initial combination, the second slot for the first round and so on.67 */68int aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,69 unsigned int key_len);70 71/**72 * aes_encrypt - Encrypt a single AES block73 * @ctx: Context struct containing the key schedule74 * @out: Buffer to store the ciphertext75 * @in: Buffer containing the plaintext76 */77void aes_encrypt(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);78 79/**80 * aes_decrypt - Decrypt a single AES block81 * @ctx: Context struct containing the key schedule82 * @out: Buffer to store the plaintext83 * @in: Buffer containing the ciphertext84 */85void aes_decrypt(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);86 87extern const u8 crypto_aes_sbox[];88extern const u8 crypto_aes_inv_sbox[];89 90void aescfb_encrypt(const struct crypto_aes_ctx *ctx, u8 *dst, const u8 *src,91 int len, const u8 iv[AES_BLOCK_SIZE]);92void aescfb_decrypt(const struct crypto_aes_ctx *ctx, u8 *dst, const u8 *src,93 int len, const u8 iv[AES_BLOCK_SIZE]);94 95#endif96