gnutls_hmac_init — API function


#include <gnutls/crypto.h>

int gnutls_hmac_init(gnutls_hmac_hd_t * dig, gnutls_mac_algorithm_t algorithm, const void * key, size_t keylen);


gnutls_hmac_hd_t * dig

is a gnutls_hmac_hd_t type

gnutls_mac_algorithm_t algorithm

the HMAC algorithm to use

const void * key

the key to be used for encryption

size_t keylen

the length of the key


This function will initialize an context that can be used to produce a Message Authentication Code (MAC) of data.  This will effectively use the current crypto backend in use by gnutls or the cryptographic accelerator in use.

Note that despite the name of this function, it can be used for other MAC algorithms than HMAC.


Zero or a negative error code on error.



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See Also

The full documentation for gnutls is maintained as a Texinfo manual. If the /usr/share/doc/gnutls/ directory does not contain the HTML form visit


3.6.9 gnutls