gnutls_aead_cipher_decryptv2 - Linux
Overview
The gnutls_aead_cipher_decryptv2 function provides an API for decrypting data using an AEAD (authenticated encryption with associated data) cipher. This capability is essential for secure data transmission and storage, ensuring data integrity and confidentiality.
Syntax
int gnutls_aead_cipher_decryptv2(gnutls_aead_cipher_context *ctx,
size_t dst_offset,
size_t src_offset,
size_t dst_length,
const void *dst,
const void *src,
const void *iv)
Options/Flags
– None.
Examples
Decrypting data using AES-GCM (Galois/Counter Mode):
#include <gnutls/gnutls.h>
void decrypt_aes_gcm(const uint8_t *key, size_t key_size,
const uint8_t *iv, size_t iv_size,
const uint8_t *ciphertext, size_t ciphertext_size,
const uint8_t *aad, size_t aad_size,
uint8_t *plaintext, size_t plaintext_size) {
gnutls_aead_cipher_context *ctx = gnutls_aead_cipher_init(GNUTLS_AEAD_AES_256_GCM);
gnutls_aead_cipher_setkey(ctx, key, key_size);
gnutls_aead_cipher_setiv(ctx, iv, iv_size);
int result = gnutls_aead_cipher_decryptv2(ctx,
0,
0,
plaintext_size,
plaintext,
ciphertext,
aad);
gnutls_aead_cipher_deinit(ctx);
}
Common Issues
- Invalid key or IV: Ensure that the key and IV match the cipher you are using and have the correct size.
- Ciphertext corruption: Verify that the ciphertext has not been modified or corrupted, as it will result in decryption failure.
- Insufficient memory: Allocate sufficient memory for the plaintext buffer to hold the decrypted data.
Integration
gnutls_aead_cipher_decryptv2 can be integrated with other cryptographic functions to create a robust security framework. For example, it can be combined with a key derivation function and a hash function to provide end-to-end data protection.
Related Commands
gnutls_aead_cipher_encryptv2gnutls_macgnutls_hash