EVP_chacha20, EVP_chacha20_poly1305 - EVP ChaCha20 stream cipher
#include <openssl/evp.h>
const EVP_CIPHER *EVP_chacha20(void);
const EVP_CIPHER *EVP_chacha20_poly1305(void);
The ChaCha20 stream cipher for EVP.
- EVP_chacha20()
- The ChaCha20 stream cipher. The key length is 256 bits, the
IV is 128 bits long. The first 64 bits consists of a counter in
little-endian order followed by a 64 bit nonce. For example a nonce of:
0000000000000002
With an initial counter of 42 (2a in hex) would be expressed as:
2a000000000000000000000000000002
- EVP_chacha20_poly1305()
- Authenticated encryption with ChaCha20-Poly1305. Like
EVP_chacha20(), the key is 256 bits and the IV is 96 bits. This
supports additional authenticated data (AAD) and produces a 128-bit
authentication tag. See the "AEAD Interface" in
EVP_EncryptInit(3) section for more information.
Developers should be aware of the negative performance implications of calling
these functions multiple times and should consider using
EVP_CIPHER_fetch(3) with
EVP_CIPHER-CHACHA(7) instead. See
"Performance" in
crypto(7) for further information.
RFC 7539 <
https://www.rfc-editor.org/rfc/rfc7539.html#section-2.4> uses a
32 bit counter and a 96 bit nonce for the IV.
These functions return an
EVP_CIPHER structure that contains the
implementation of the symmetric cipher. See
EVP_CIPHER_meth_new(3) for
details of the
EVP_CIPHER structure.
evp(7),
EVP_EncryptInit(3),
EVP_CIPHER_meth_new(3)
Copyright 2017-2023 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy in the
file LICENSE in the source distribution or at
<
https://www.openssl.org/source/license.html>.