gnutls\_aead\_cipher\_decrypt(3) gnutls gnutls\_aead\_cipher\_decrypt(3)

# [NAME](#NAME)

gnutls\_aead\_cipher\_decrypt - API function

# [SYNOPSIS](#SYNOPSIS)

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

**int gnutls\_aead\_cipher\_decrypt(gnutls\_aead\_cipher\_hd\_t handle, const void * nonce, size\_t nonce\_len, const void * auth, size\_t auth\_len, size\_t tag\_size, const void * ctext, size\_t ctext\_len, void * ptext, size\_t * ptext\_len);**

# [ARGUMENTS](#ARGUMENTS)

[gnutls\_aead\_cipher\_hd\_t handle](#gnutls_aead_cipher_hd_t)

is a **gnutls\_aead\_cipher\_hd\_t** type.

[const void * nonce](#const)

the nonce to set

[size\_t nonce\_len](#size_t)

The length of the nonce

[const void * auth](#const~2)

additional data to be authenticated

[size\_t auth\_len](#size_t~2)

The length of the data

[size\_t tag\_size](#size_t~3)

The size of the tag to use (use zero for the default)

[const void * ctext](#const~3)

the data to decrypt (including the authentication tag)

[size\_t ctext\_len](#size_t~4)

the length of data to decrypt (includes tag size)

[void * ptext](#void)

the decrypted data

[size\_t * ptext\_len](#size_t~5)

the length of decrypted data (initially must hold the maximum available size)

# [DESCRIPTION](#DESCRIPTION)

This function will decrypt the given data using the algorithm specified by the context. This function must be provided the complete data to be decrypted, including the authentication tag. On several AEAD ciphers, the authentication tag is appended to the ciphertext, though this is not a general rule. This function will fail if the tag verification fails.

# [RETURNS](#RETURNS)

Zero or a negative error code on verification failure or other error.

# [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_aead_cipher_decrypt(3) from gnutls 3.8.13-r3 (Chainguard OS)
Source: https://gitlab.com/gnutls/gnutls