hmac.h File Reference

Keyed-Hashing for Message Authentication. More...

#include <ipxe/crypto.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
static void	hmac_update (struct digest_algorithm *digest, void *digest_ctx, const void *data, size_t len)
	Update HMAC. More...
void	hmac_init (struct digest_algorithm *digest, void *digest_ctx, void *key, size_t *key_len)
	Initialise HMAC. More...
void	hmac_final (struct digest_algorithm *digest, void *digest_ctx, void *key, size_t *key_len, void *hmac)
	Finalise HMAC. More...

Detailed Description

Keyed-Hashing for Message Authentication.

Definition in file hmac.h.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

hmac_update()

static void hmac_update ( struct digest_algorithm *  digest, void *  digest_ctx, const void *  data, size_t  len  )

inlinestatic

Update HMAC.

Parameters

digest	Digest algorithm to use
digest_ctx	Digest context
data	Data
len	Length of data

Definition at line 21 of file hmac.h.

                                              {
        digest_update ( digest, digest_ctx, data, len );
}

References data, digest, digest_update(), and len.

Referenced by ccmp_kie_mic(), hmac_drbg_update_key(), hmac_drbg_update_value(), ntlm_key(), ntlm_response(), pbkdf2_sha1_f(), peerdist_info_passphrase_okx(), peerdist_info_segment_hash(), prf_sha1(), tkip_kie_mic(), tls_hmac_init(), tls_hmac_update(), tls_hmac_update_va(), and tls_p_hash_va().

hmac_init()

void hmac_init	(	struct digest_algorithm *	digest,
		void *	digest_ctx,
		void *	key,
		size_t *	key_len
	)

Initialise HMAC.

Parameters

digest	Digest algorithm to use
digest_ctx	Digest context
key	Key
key_len	Length of key

The length of the key should be less than the block size of the digest algorithm being used. (If the key length is greater, it will be replaced with its own digest, and key_len will be updated accordingly).

Definition at line 80 of file hmac.c.

                                              {
        unsigned char k_ipad[digest->blocksize];
        unsigned int i;

        /* Reduce key if necessary */
        if ( *key_len > sizeof ( k_ipad ) )
                hmac_reduce_key ( digest, key, key_len );

        /* Construct input pad */
        memset ( k_ipad, 0, sizeof ( k_ipad ) );
        memcpy ( k_ipad, key, *key_len );
        for ( i = 0 ; i < sizeof ( k_ipad ) ; i++ ) {
                k_ipad[i] ^= 0x36;
        }
        
        /* Start inner hash */
        digest_init ( digest, digest_ctx );
        digest_update ( digest, digest_ctx, k_ipad, sizeof ( k_ipad ) );
}

References digest, digest_init(), digest_update(), hmac_reduce_key(), key, memcpy(), and memset().

Referenced by ccmp_kie_mic(), hmac_drbg_update_key(), hmac_drbg_update_value(), ntlm_key(), ntlm_response(), pbkdf2_sha1_f(), peerdist_info_passphrase_okx(), peerdist_info_segment_hash(), prf_sha1(), tkip_kie_mic(), tls_hmac_init(), and tls_p_hash_va().

hmac_final()

void hmac_final	(	struct digest_algorithm *	digest,
		void *	digest_ctx,
		void *	key,
		size_t *	key_len,
		void *	hmac
	)

Finalise HMAC.

Parameters

digest	Digest algorithm to use
digest_ctx	Digest context
key	Key
key_len	Length of key
hmac	HMAC digest to fill in

The length of the key should be less than the block size of the digest algorithm being used. (If the key length is greater, it will be replaced with its own digest, and key_len will be updated accordingly).

Definition at line 115 of file hmac.c.

                                                           {
        unsigned char k_opad[digest->blocksize];
        unsigned int i;

        /* Reduce key if necessary */
        if ( *key_len > sizeof ( k_opad ) )
                hmac_reduce_key ( digest, key, key_len );

        /* Construct output pad */
        memset ( k_opad, 0, sizeof ( k_opad ) );
        memcpy ( k_opad, key, *key_len );
        for ( i = 0 ; i < sizeof ( k_opad ) ; i++ ) {
                k_opad[i] ^= 0x5c;
        }
        
        /* Finish inner hash */
        digest_final ( digest, digest_ctx, hmac );

        /* Perform outer hash */
        digest_init ( digest, digest_ctx );
        digest_update ( digest, digest_ctx, k_opad, sizeof ( k_opad ) );
        digest_update ( digest, digest_ctx, hmac, digest->digestsize );
        digest_final ( digest, digest_ctx, hmac );
}

References digest, digest_final(), digest_init(), digest_update(), hmac_reduce_key(), key, memcpy(), and memset().

Referenced by ccmp_kie_mic(), hmac_drbg_update_key(), hmac_drbg_update_value(), ntlm_key(), ntlm_response(), pbkdf2_sha1_f(), peerdist_info_passphrase_okx(), peerdist_info_segment_hash(), prf_sha1(), tkip_kie_mic(), tls_hmac_final(), and tls_p_hash_va().