AES

AES block cipher (FIPS 197), on single blocks or in ECB mode. More...

Data Structures
struct	pbl_aes_ctx
	Expanded key. More...

Macros
#define	PBL_AES_BLOCK_SIZE   16U
	Size of a block, in bytes.
#define	PBL_AES_KEYSIZE_128   16U
	Size of an AES-128 key, in bytes.
#define	PBL_AES_KEYSIZE_192   24U
	Size of an AES-192 key, in bytes.
#define	PBL_AES_KEYSIZE_256   32U
	Size of an AES-256 key, in bytes.
#define	PBL_AES_MAX_KEYLENGTH_U32   60U
	Most 32-bit words in a key schedule, for AES-256.

Functions
int	pbl_aes_expandkey (struct pbl_aes_ctx *ctx, const uint8_t *key, size_t key_len)
	Expand a key.
void	pbl_aes_encrypt (const struct pbl_aes_ctx *ctx, uint8_t out[PBL_AES_BLOCK_SIZE], const uint8_t in[PBL_AES_BLOCK_SIZE])
	Encrypt a block.
void	pbl_aes_decrypt (const struct pbl_aes_ctx *ctx, uint8_t out[PBL_AES_BLOCK_SIZE], const uint8_t in[PBL_AES_BLOCK_SIZE])
	Decrypt a block.
int	pbl_aes_ecb_encrypt (const struct pbl_aes_ctx *ctx, uint8_t *out, const uint8_t *in, size_t len)
	Encrypt blocks in ECB mode.
int	pbl_aes_ecb_decrypt (const struct pbl_aes_ctx *ctx, uint8_t *out, const uint8_t *in, size_t len)
	Decrypt blocks in ECB mode.

Detailed Description

AES block cipher (FIPS 197), on single blocks or in ECB mode.

Runs of at least CONFIG_CRYPTO_AES_HW_MIN_LEN bytes are processed by a hardware accelerator when a driver provides one (see Crypto), the rest in software. Other modes of operation are built by the caller.

struct pbl_aes_ctx ctx;
 
ret = pbl_aes_expandkey(&ctx, key, PBL_AES_KEYSIZE_128);
ret = pbl_aes_ecb_encrypt(&ctx, buf, buf, len);

---

Data Structure Documentation

pbl_aes_ctx

struct pbl_aes_ctx

Expanded key.

Data Fields
uint32_t	key_dec[PBL_AES_MAX_KEYLENGTH_U32]	Decryption round keys.
uint32_t	key_enc[PBL_AES_MAX_KEYLENGTH_U32]	Encryption round keys; the first words are the key itself.
uint32_t	key_length	Key length in bytes.

Macro Definition Documentation

PBL_AES_BLOCK_SIZE

#define PBL_AES_BLOCK_SIZE   16U

Size of a block, in bytes.

PBL_AES_KEYSIZE_128

#define PBL_AES_KEYSIZE_128   16U

Size of an AES-128 key, in bytes.

PBL_AES_KEYSIZE_192

#define PBL_AES_KEYSIZE_192   24U

Size of an AES-192 key, in bytes.

PBL_AES_KEYSIZE_256

#define PBL_AES_KEYSIZE_256   32U

Size of an AES-256 key, in bytes.

PBL_AES_MAX_KEYLENGTH_U32

#define PBL_AES_MAX_KEYLENGTH_U32   60U

Most 32-bit words in a key schedule, for AES-256.

Function Documentation

pbl_aes_decrypt()

void pbl_aes_decrypt	(	const struct pbl_aes_ctx *	ctx,
		uint8_t	out[PBL_AES_BLOCK_SIZE],
		const uint8_t	in[PBL_AES_BLOCK_SIZE]
	)

Decrypt a block.

Parameters

	ctx	Expanded key.
[out]	out	Plaintext, which may be in.
	in	Ciphertext.

pbl_aes_ecb_decrypt()

int pbl_aes_ecb_decrypt	(	const struct pbl_aes_ctx *	ctx,
		uint8_t *	out,
		const uint8_t *	in,
		size_t	len
	)

Decrypt blocks in ECB mode.

Parameters

	ctx	Expanded key.
[out]	out	Plaintext, which may be in.
	in	Ciphertext.
	len	Length of in in bytes, a multiple of PBL_AES_BLOCK_SIZE.

Return values

0	on success.
-EINVAL	if len is not a multiple of PBL_AES_BLOCK_SIZE.

pbl_aes_ecb_encrypt()

int pbl_aes_ecb_encrypt	(	const struct pbl_aes_ctx *	ctx,
		uint8_t *	out,
		const uint8_t *	in,
		size_t	len
	)

Encrypt blocks in ECB mode.

Parameters

	ctx	Expanded key.
[out]	out	Ciphertext, which may be in.
	in	Plaintext.
	len	Length of in in bytes, a multiple of PBL_AES_BLOCK_SIZE.

Return values

0	on success.
-EINVAL	if len is not a multiple of PBL_AES_BLOCK_SIZE.

pbl_aes_encrypt()

void pbl_aes_encrypt	(	const struct pbl_aes_ctx *	ctx,
		uint8_t	out[PBL_AES_BLOCK_SIZE],
		const uint8_t	in[PBL_AES_BLOCK_SIZE]
	)

Encrypt a block.

Parameters

	ctx	Expanded key.
[out]	out	Ciphertext, which may be in.
	in	Plaintext.

pbl_aes_expandkey()

int pbl_aes_expandkey	(	struct pbl_aes_ctx *	ctx,
		const uint8_t *	key,
		size_t	key_len
	)

Expand a key.

Parameters

[out]	ctx	Expanded key.
	key	Key.
	key_len	Length of key in bytes: PBL_AES_KEYSIZE_128, PBL_AES_KEYSIZE_192 or PBL_AES_KEYSIZE_256.

Return values

0	on success.
-EINVAL	if key_len is not a valid key size.