83 lines
2.4 KiB
C
Executable file
83 lines
2.4 KiB
C
Executable file
/* $OpenBSD: e_chacha.c,v 1.8 2020/01/26 07:47:26 tb Exp $ */
|
|
/*
|
|
* Copyright (c) 2014 Joel Sing <jsing@openbsd.org>
|
|
*
|
|
* Permission to use, copy, modify, and distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
#include <openssl/opensslconf.h>
|
|
|
|
#ifndef OPENSSL_NO_CHACHA
|
|
|
|
#include <openssl/chacha.h>
|
|
#include <openssl/evp.h>
|
|
#include <openssl/objects.h>
|
|
|
|
#include "evp_locl.h"
|
|
|
|
static int chacha_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
|
|
const unsigned char *in, size_t len);
|
|
static int chacha_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
|
|
const unsigned char *iv, int enc);
|
|
|
|
static const EVP_CIPHER chacha20_cipher = {
|
|
.nid = NID_chacha20,
|
|
.block_size = 1,
|
|
.key_len = 32,
|
|
/*
|
|
* The 128 bit EVP IV is split for ChaCha into four 32 bit pieces:
|
|
* counter[0] counter[1] iv[0] iv[1]
|
|
* OpenSSL exposes these as:
|
|
* openssl_iv = counter[0] iv[0] iv[1] iv[2]
|
|
* Due to the cipher internal state's symmetry, these are functionally
|
|
* equivalent.
|
|
*/
|
|
.iv_len = 16,
|
|
.flags = EVP_CIPH_STREAM_CIPHER | EVP_CIPH_ALWAYS_CALL_INIT |
|
|
EVP_CIPH_CUSTOM_IV,
|
|
.init = chacha_init,
|
|
.do_cipher = chacha_cipher,
|
|
.ctx_size = sizeof(ChaCha_ctx)
|
|
};
|
|
|
|
const EVP_CIPHER *
|
|
EVP_chacha20(void)
|
|
{
|
|
return (&chacha20_cipher);
|
|
}
|
|
|
|
static int
|
|
chacha_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
|
|
const unsigned char *openssl_iv, int enc)
|
|
{
|
|
if (key != NULL)
|
|
ChaCha_set_key((ChaCha_ctx *)ctx->cipher_data, key,
|
|
EVP_CIPHER_CTX_key_length(ctx) * 8);
|
|
if (openssl_iv != NULL) {
|
|
const unsigned char *iv = openssl_iv + 8;
|
|
const unsigned char *counter = openssl_iv;
|
|
|
|
ChaCha_set_iv((ChaCha_ctx *)ctx->cipher_data, iv, counter);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
chacha_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, const unsigned char *in,
|
|
size_t len)
|
|
{
|
|
ChaCha((ChaCha_ctx *)ctx->cipher_data, out, in, len);
|
|
return 1;
|
|
}
|
|
|
|
#endif
|