---
name: "gnutls_aead_cipher_decrypt"
section: "3"
platform: "linux"
package: "gnutls"
version: "3.8.13-3"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/gnutls_aead_cipher_decrypt"
---

# gnutls\_aead\_cipher\_decrypt(3)

API function

## NAME

gnutls\_aead\_cipher\_decrypt - API function

## 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

- gnutls\_aead\_cipher\_hd\_t handle

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

- const void \* nonce

  the nonce to set

- size\_t nonce\_len

  The length of the nonce

- const void \* auth

  additional data to be authenticated

- size\_t auth\_len

  The length of the data

- size\_t tag\_size

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

- const void \* ctext

  the data to decrypt (including the authentication tag)

- size\_t ctext\_len

  the length of data to decrypt (includes tag size)

- void \* ptext

  the decrypted data

- size\_t \* ptext\_len

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

## 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

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

## SINCE

3\.4.0

## REPORTING BUGS

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

## 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

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/