aes.h File Reference

AES algorithm. More...

#include <ipxe/crypto.h>

Go to the source code of this file.

Data Structures
union	aes_matrix
	AES matrix. More...
struct	aes_round_keys
	AES round keys. More...
struct	aes_context
	AES context. More...

Macros
#define	AES_BLOCKSIZE   16
	AES blocksize. More...
#define	AES_MAX_ROUNDS   15
	Maximum number of AES rounds. More...
#define	AES_CTX_SIZE   sizeof ( struct aes_context )
	AES context size. More...

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
int	aes_wrap (const void *kek, const void *src, void *dest, int nblk)
	Wrap a key or other data using AES Key Wrap (RFC 3394) More...
int	aes_unwrap (const void *kek, const void *src, void *dest, int nblk)
	Unwrap a key or other data using AES Key Wrap (RFC 3394) More...

Variables
struct cipher_algorithm	aes_algorithm
	Basic AES algorithm. More...
struct cipher_algorithm	aes_ecb_algorithm
struct cipher_algorithm	aes_cbc_algorithm
struct cipher_algorithm	aes_gcm_algorithm

Detailed Description

AES algorithm.

Definition in file aes.h.

Macro Definition Documentation

AES_BLOCKSIZE

#define AES_BLOCKSIZE   16

AES blocksize.

Definition at line 15 of file aes.h.

AES_MAX_ROUNDS

#define AES_MAX_ROUNDS   15

Maximum number of AES rounds.

Definition at line 18 of file aes.h.

AES_CTX_SIZE

#define AES_CTX_SIZE   sizeof ( struct aes_context )

AES context size.

Definition at line 45 of file aes.h.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

aes_wrap()

int aes_wrap	(	const void *	kek,
		const void *	src,
		void *	dest,
		int	nblk
	)

Wrap a key or other data using AES Key Wrap (RFC 3394)

Parameters

kek	Key Encryption Key, 16 bytes
src	Data to encrypt
nblk	Number of 8-byte blocks in data

Return values

dest	Encrypted data (8 bytes longer than input)

The algorithm is implemented such that src and dest may point to the same buffer.

Definition at line 38 of file aes_wrap.c.

{
        u8 *A = dest;
        u8 B[16];
        u8 *R;
        int i, j;
        void *aes_ctx = malloc ( AES_CTX_SIZE );

        if ( ! aes_ctx )
                return -1;

        cipher_setkey ( &aes_algorithm, aes_ctx, kek, 16 );

        /* Set up */
        memset ( A, 0xA6, 8 );
        memmove ( dest + 8, src, nblk * 8 );

        /* Wrap */
        for ( j = 0; j < 6; j++ ) {
                R = dest + 8;
                for ( i = 1; i <= nblk; i++ ) {
                        memcpy ( B, A, 8 );
                        memcpy ( B + 8, R, 8 );
                        cipher_encrypt ( &aes_algorithm, aes_ctx, B, B, 16 );
                        memcpy ( A, B, 8 );
                        A[7] ^= ( nblk * j ) + i;
                        memcpy ( R, B + 8, 8 );
                        R += 8;
                }
        }

        free ( aes_ctx );
        return 0;
}

References aes_algorithm, AES_CTX_SIZE, cipher_encrypt, cipher_setkey(), dest, free, kek, malloc(), memcpy(), memmove(), memset(), and src.

aes_unwrap()

int aes_unwrap	(	const void *	kek,
		const void *	src,
		void *	dest,
		int	nblk
	)

Unwrap a key or other data using AES Key Wrap (RFC 3394)

Parameters

kek	Key Encryption Key, 16 bytes
src	Data to decrypt
nblk	Number of 8-byte blocks in plaintext key

Return values

dest	Decrypted data (8 bytes shorter than input)
rc	Zero on success, nonzero on IV mismatch

The algorithm is implemented such that src and dest may point to the same buffer.

Definition at line 85 of file aes_wrap.c.

{
        u8 A[8], B[16];
        u8 *R;
        int i, j;
        void *aes_ctx = malloc ( AES_CTX_SIZE );

        if ( ! aes_ctx )
                return -1;

        cipher_setkey ( &aes_algorithm, aes_ctx, kek, 16 );

        /* Set up */
        memcpy ( A, src, 8 );
        memmove ( dest, src + 8, nblk * 8 );

        /* Unwrap */
        for ( j = 5; j >= 0; j-- ) {
                R = dest + ( nblk - 1 ) * 8;
                for ( i = nblk; i >= 1; i-- ) {
                        memcpy ( B, A, 8 );
                        memcpy ( B + 8, R, 8 );
                        B[7] ^= ( nblk * j ) + i;
                        cipher_decrypt ( &aes_algorithm, aes_ctx, B, B, 16 );
                        memcpy ( A, B, 8 );
                        memcpy ( R, B + 8, 8 );
                        R -= 8;
                }
        }

        free ( aes_ctx );

        /* Check IV */
        for ( i = 0; i < 8; i++ ) {
                if ( A[i] != 0xA6 )
                        return -1;
        }

        return 0;
}

References aes_algorithm, AES_CTX_SIZE, cipher_decrypt, cipher_setkey(), dest, free, kek, malloc(), memcpy(), memmove(), and src.

Referenced by ccmp_kie_decrypt().

Variable Documentation

aes_algorithm

struct cipher_algorithm aes_algorithm

Basic AES algorithm.

Definition at line 783 of file aes.c.

Referenced by aes_unwrap(), aes_wrap(), ccmp_cbc_mac(), ccmp_ctr_xor(), ccmp_feed_cbc_mac(), and ccmp_init().

aes_ecb_algorithm

struct cipher_algorithm aes_ecb_algorithm

Referenced by aes_test_exec().

aes_cbc_algorithm

struct cipher_algorithm aes_cbc_algorithm

Referenced by aes_test_exec(), and peerblk_parse_header().

aes_gcm_algorithm

struct cipher_algorithm aes_gcm_algorithm

Referenced by gcm_test_exec().