gnutls\_crypto\_register\_mac(3) gnutls gnutls\_crypto\_register\_mac(3)

# [NAME](#NAME)

gnutls\_crypto\_register\_mac - API function

# [SYNOPSIS](#SYNOPSIS)

**#include <gnutls/crypto.h>**

**int gnutls\_crypto\_register\_mac(gnutls\_mac\_algorithm\_t algorithm, int priority, gnutls\_mac\_init\_func init, gnutls\_mac\_setkey\_func setkey, gnutls\_mac\_setnonce\_func setnonce, gnutls\_mac\_hash\_func hash, gnutls\_mac\_output\_func output, gnutls\_mac\_deinit\_func deinit, gnutls\_mac\_fast\_func hash\_fast);**

# [ARGUMENTS](#ARGUMENTS)

[gnutls\_mac\_algorithm\_t algorithm](#gnutls_mac_algorithm_t)

is the gnutls MAC identifier

[int priority](#int)

is the priority of the algorithm

[gnutls\_mac\_init\_func init](#gnutls_mac_init_func)

A function which initializes the MAC

[gnutls\_mac\_setkey\_func setkey](#gnutls_mac_setkey_func)

A function which sets the key of the MAC

[gnutls\_mac\_setnonce\_func setnonce](#gnutls_mac_setnonce_func)

A function which sets the nonce for the mac (may be **NULL** for common MAC algorithms)

[gnutls\_mac\_hash\_func hash](#gnutls_mac_hash_func)

Perform the hash operation

[gnutls\_mac\_output\_func output](#gnutls_mac_output_func)

Provide the output of the MAC

[gnutls\_mac\_deinit\_func deinit](#gnutls_mac_deinit_func)

A function which deinitializes the MAC

[gnutls\_mac\_fast\_func hash\_fast](#gnutls_mac_fast_func)

Perform the MAC operation in one go

# [DESCRIPTION](#DESCRIPTION)

This function will register a MAC algorithm to be used by gnutls. Any algorithm registered will override the included algorithms and by convention kernel implemented algorithms have priority of 90 and CPU-assisted of 80. The algorithm with the lowest priority will be used by gnutls.

# [DEPRECATED](#DEPRECATED)

since 3.7.0 it is no longer possible to override cipher implementation

# [RETURNS](#RETURNS)

**GNUTLS\_E\_SUCCESS** on success, otherwise a negative error code.

# [SINCE](#SINCE)

3.4.0

# [REPORTING BUGS](#REPORTING_BUGS)

Report bugs to <bugs@gnutls.org>.  
Home page: https://www.gnutls.org

# [COPYRIGHT](#COPYRIGHT)

Copyright © 2001-2023 Free Software Foundation, Inc., and others.  
Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved.

# [SEE ALSO](#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

[https://www.gnutls.org/manual/](https://www.gnutls.org/manual/)

3.8.13 gnutls

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Document: gnutls_crypto_register_mac(3) from gnutls 3.8.13-r1 (Chainguard OS)
Source: https://gitlab.com/gnutls/gnutls