1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Common values for AES algorithms
9 #include <linux/types.h>
10 #include <linux/crypto.h>
12 #define AES_MIN_KEY_SIZE 16
13 #define AES_MAX_KEY_SIZE 32
14 #define AES_KEYSIZE_128 16
15 #define AES_KEYSIZE_192 24
16 #define AES_KEYSIZE_256 32
17 #define AES_BLOCK_SIZE 16
18 #define AES_MAX_KEYLENGTH (15 * 16)
19 #define AES_MAX_KEYLENGTH_U32 (AES_MAX_KEYLENGTH / sizeof(u32))
22 * Please ensure that the first two fields are 16-byte aligned
23 * relative to the start of the structure, i.e., don't move them!
25 struct crypto_aes_ctx {
26 u32 key_enc[AES_MAX_KEYLENGTH_U32];
27 u32 key_dec[AES_MAX_KEYLENGTH_U32];
31 extern const u32 crypto_ft_tab[4][256] ____cacheline_aligned;
32 extern const u32 crypto_fl_tab[4][256] ____cacheline_aligned;
33 extern const u32 crypto_it_tab[4][256] ____cacheline_aligned;
34 extern const u32 crypto_il_tab[4][256] ____cacheline_aligned;
36 int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
37 unsigned int key_len);
40 * aes_expandkey - Expands the AES key as described in FIPS-197
41 * @ctx: The location where the computed key will be stored.
42 * @in_key: The supplied key.
43 * @key_len: The length of the supplied key.
45 * Returns 0 on success. The function fails only if an invalid key size (or
46 * pointer) is supplied.
47 * The expanded key size is 240 bytes (max of 14 rounds with a unique 16 bytes
48 * key schedule plus a 16 bytes key which is used before the first round).
49 * The decryption key is prepared for the "Equivalent Inverse Cipher" as
50 * described in FIPS-197. The first slot (16 bytes) of each key (enc or dec) is
51 * for the initial combination, the second slot for the first round and so on.
53 int aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
54 unsigned int key_len);
57 * aes_encrypt - Encrypt a single AES block
58 * @ctx: Context struct containing the key schedule
59 * @out: Buffer to store the ciphertext
60 * @in: Buffer containing the plaintext
62 void aes_encrypt(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);
65 * aes_decrypt - Decrypt a single AES block
66 * @ctx: Context struct containing the key schedule
67 * @out: Buffer to store the plaintext
68 * @in: Buffer containing the ciphertext
70 void aes_decrypt(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);