crypto_chacha20_encrypt,
crypto_chacha20_init,
crypto_chacha20_x_init,
crypto_chacha20_stream,
crypto_chacha20_set_ctr —
deprecated Chacha20 and XChacha20 encryption
functions
#include
<monocypher.h>
void
crypto_chacha20_init(
crypto_chacha_ctx
*ctx,
const uint8_t key[32],
const uint8_t nonce[8]);
void
crypto_chacha20_x_init(
crypto_chacha_ctx
*ctx,
const uint8_t key[32],
const uint8_t nonce[24]);
void
crypto_chacha20_encrypt(
crypto_chacha_ctx
*ctx,
uint8_t *cipher_text,
const uint8_t *plain_text,
size_t text_size);
void
crypto_chacha20_stream(
crypto_chacha_ctx
*ctx,
uint8_t *stream,
size_t stream_size);
void
crypto_chacha20_set_ctr(
crypto_chacha_ctx
*ctx,
uint64_t ctr);
These functions provided an incremental interface for the Chacha20 cipher. They
are deprecated in favor of
crypto_chacha20(3monocypher),
crypto_chacha20_ctr(3monocypher),
crypto_xchacha20(3monocypher),
and
crypto_xchacha20_ctr(3monocypher).
For encryption, you can achieve an identical effect as the deprecated functions
by using
crypto_chacha20_ctr(3monocypher)
or
crypto_xchacha20_ctr(3monocypher).
Care needs to be taken with regards to handling the counter value when
migrating old code to use the new functions. The new functions
always return next counter value. This means that
input ciphertexts or plaintexts whose lengths are not exactly multiples of 64
bytes advance the counter, even though there is theoretically some space left
in a Chacha20 block. New applications should design their code so that either
the protocl is not reliant on the counter covering the entire text (e.g. by
cutting input into independent chunks) or inputs are always such that their
lengths are multiples of 64 bytes (e.g. by buffering input until 64 bytes have
been obtained).
To obtain the raw Chacha20 stream previously provided by
crypto_chacha20_stream(), pass
NULL to
crypto_chacha20 as
plaintext.
These functions return nothing.
crypto_chacha20(3monocypher),
crypto_chacha20_ctr(3monocypher),
crypto_xchacha20(3monocypher),
crypto_xchacha20_ctr(3monocypher),
crypto_lock(3monocypher),
crypto_wipe(3monocypher),
intro(3monocypher)
The
crypto_chacha20_encrypt(),
crypto_chacha20_init(), functions first appeared
in Monocypher 0.1.
crypto_chacha20_stream() was
added in Monocypher 0.2.
crypto_chacha20_x_init()
and
crypto_chacha20_set_ctr() were added in
Monocypher 1.0. They were deprecated in Monocypher 3.0.0 and will be removed
in Monocypher 4.0.0.