OrgApache/incubator-nuttx
OrgApache
/
incubator-nuttx
mirror of https://github.com/apache/incubator-nuttx.git
1
0
Fork 0
Code Issues Releases Wiki Activity
incubator-nuttx/crypto/chachapoly.c

299 lines
8.2 KiB
C
Raw Blame History

/****************************************************************************
* crypto/chachapoly.c
* $OpenBSD: chachapoly.c,v 1.6 2020/07/22 13:54:30 tobhe Exp $
*
* Copyright (c) 2015 Mike Belopuhov
*
* 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.
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <endian.h>
#include <sys/param.h>
#include <crypto/poly1305.h>
#include <crypto/chachapoly.h>
#include "chacha_private.h"
/****************************************************************************
* Private Data
****************************************************************************/
static const uint8_t pad0[16];
/****************************************************************************
* Public Functions
****************************************************************************/
int chacha20_setkey(FAR void *sched, FAR uint8_t *key, int len)
{
FAR struct chacha20_ctx *ctx = (FAR struct chacha20_ctx *)sched;
if (len != CHACHA20_KEYSIZE + CHACHA20_SALT)
{
return -1;
}
/* initial counter is 1 */
ctx->nonce[0] = 1;
memcpy(ctx->nonce + CHACHA20_CTR, key + CHACHA20_KEYSIZE,
CHACHA20_SALT);
chacha_keysetup((FAR chacha_ctx *)&ctx->block, key, CHACHA20_KEYSIZE * 8);
return 0;
}
void chacha20_reinit(caddr_t key, FAR uint8_t *iv)
{
FAR struct chacha20_ctx *ctx = (FAR struct chacha20_ctx *)key;
chacha_ivsetup((FAR chacha_ctx *)ctx->block, iv, ctx->nonce);
}
void chacha20_crypt(caddr_t key, FAR uint8_t *data)
{
FAR struct chacha20_ctx *ctx = (FAR struct chacha20_ctx *)key;
chacha_encrypt_bytes((FAR chacha_ctx *)ctx->block, data, data,
CHACHA20_BLOCK_LEN);
}
void chacha20_poly1305_init(FAR void *xctx)
{
FAR CHACHA20_POLY1305_CTX *ctx = xctx;
memset(ctx, 0, sizeof(*ctx));
}
void chacha20_poly1305_setkey(FAR void *xctx, FAR const uint8_t *key,
uint16_t klen)
{
FAR CHACHA20_POLY1305_CTX *ctx = xctx;
/* salt is provided with the key material */
memcpy(ctx->nonce + CHACHA20_CTR, key + CHACHA20_KEYSIZE,
CHACHA20_SALT);
chacha_keysetup((FAR chacha_ctx *)&ctx->chacha, key, CHACHA20_KEYSIZE * 8);
}
void chacha20_poly1305_reinit(FAR void *xctx, FAR const uint8_t *iv,
uint16_t ivlen)
{
FAR CHACHA20_POLY1305_CTX *ctx = xctx;
/* initial counter is 0 */
chacha_ivsetup((FAR chacha_ctx *)&ctx->chacha, iv, ctx->nonce);
chacha_encrypt_bytes((FAR chacha_ctx *)&ctx->chacha, ctx->key, ctx->key,
POLY1305_KEYLEN);
poly1305_init((FAR poly1305_state *)&ctx->poly, ctx->key);
}
int chacha20_poly1305_update(FAR void *xctx, FAR const uint8_t *data,
uint16_t len)
{
static const unsigned char zeroes[POLY1305_BLOCK_LEN];
FAR CHACHA20_POLY1305_CTX *ctx = xctx;
size_t rem;
poly1305_update((FAR poly1305_state *)&ctx->poly, data, len);
/* number of bytes in the last 16 byte block */
rem = (len + POLY1305_BLOCK_LEN) & (POLY1305_BLOCK_LEN - 1);
if (rem > 0)
{
poly1305_update((FAR poly1305_state *)&ctx->poly, zeroes,
POLY1305_BLOCK_LEN - rem);
}
return 0;
}
void chacha20_poly1305_final(FAR uint8_t *tag, FAR void *xctx)
{
FAR CHACHA20_POLY1305_CTX *ctx = xctx;
poly1305_finish((FAR poly1305_state *)&ctx->poly, tag);
explicit_bzero(ctx, sizeof(*ctx));
}
void chacha20poly1305_encrypt(
FAR uint8_t *dst,
FAR const uint8_t *src,
const size_t src_len,
FAR const uint8_t *ad,
const size_t ad_len,
const uint64_t nonce,
FAR const uint8_t *key)
{
poly1305_state poly1305_ctx;
chacha_ctx ctx;
union
{
uint8_t b0[CHACHA20POLY1305_KEY_SIZE];
uint64_t lens[2];
} b =
{
{
0
}
};
uint64_t le_nonce = htole64(nonce);
chacha_keysetup(&ctx, key, CHACHA20POLY1305_KEY_SIZE * 8);
chacha_ivsetup(&ctx, (FAR uint8_t *) &le_nonce, NULL);
chacha_encrypt_bytes(&ctx, b.b0, b.b0, sizeof(b.b0));
poly1305_init(&poly1305_ctx, b.b0);
poly1305_update(&poly1305_ctx, ad, ad_len);
poly1305_update(&poly1305_ctx, pad0, (0x10 - ad_len) & 0xf);
chacha_encrypt_bytes(&ctx, (FAR uint8_t *)src, dst, src_len);
poly1305_update(&poly1305_ctx, dst, src_len);
poly1305_update(&poly1305_ctx, pad0, (0x10 - src_len) & 0xf);
b.lens[0] = htole64(ad_len);
b.lens[1] = htole64(src_len);
poly1305_update(&poly1305_ctx, (FAR uint8_t *)b.lens, sizeof(b.lens));
poly1305_finish(&poly1305_ctx, dst + src_len);
explicit_bzero(&ctx, sizeof(chacha_ctx));
explicit_bzero(&b, sizeof(b));
}
int chacha20poly1305_decrypt(
FAR uint8_t *dst,
FAR const uint8_t *src,
const size_t src_len,
FAR const uint8_t *ad,
const size_t ad_len,
const uint64_t nonce,
FAR const uint8_t *key)
{
poly1305_state poly1305_ctx;
chacha_ctx ctx;
int ret;
size_t dst_len;
union {
uint8_t b0[CHACHA20POLY1305_KEY_SIZE];
uint8_t mac[CHACHA20POLY1305_AUTHTAG_SIZE];
uint64_t lens[2];
} b =
{
{
0
}
};
uint64_t le_nonce = htole64(nonce);
if (src_len < CHACHA20POLY1305_AUTHTAG_SIZE)
{
return 0;
}
chacha_keysetup(&ctx, key, CHACHA20POLY1305_KEY_SIZE * 8);
chacha_ivsetup(&ctx, (FAR uint8_t *) &le_nonce, NULL);
chacha_encrypt_bytes(&ctx, b.b0, b.b0, sizeof(b.b0));
poly1305_init(&poly1305_ctx, b.b0);
poly1305_update(&poly1305_ctx, ad, ad_len);
poly1305_update(&poly1305_ctx, pad0, (0x10 - ad_len) & 0xf);
dst_len = src_len - CHACHA20POLY1305_AUTHTAG_SIZE;
poly1305_update(&poly1305_ctx, src, dst_len);
poly1305_update(&poly1305_ctx, pad0, (0x10 - dst_len) & 0xf);
b.lens[0] = htole64(ad_len);
b.lens[1] = htole64(dst_len);
poly1305_update(&poly1305_ctx, (FAR uint8_t *)b.lens, sizeof(b.lens));
poly1305_finish(&poly1305_ctx, b.mac);
ret = timingsafe_bcmp(b.mac, src + dst_len, CHACHA20POLY1305_AUTHTAG_SIZE);
if (!ret)
{
chacha_encrypt_bytes(&ctx, (FAR uint8_t *) src, dst, dst_len);
}
explicit_bzero(&ctx, sizeof(chacha_ctx));
explicit_bzero(&b, sizeof(b));
return !ret;
}
void xchacha20poly1305_encrypt(
FAR uint8_t *dst,
FAR const uint8_t *src,
const size_t src_len,
FAR const uint8_t *ad,
const size_t ad_len,
FAR const uint8_t *nonce,
FAR const uint8_t *key)
{
int i;
uint32_t derived_key[CHACHA20POLY1305_KEY_SIZE / sizeof(uint32_t)];
uint64_t h_nonce;
memcpy(&h_nonce, nonce + 16, sizeof(h_nonce));
h_nonce = le64toh(h_nonce);
hchacha20(derived_key, nonce, key);
for (i = 0; i < (sizeof(derived_key) / sizeof(derived_key[0])); i++)
{
derived_key[i] = htole32(derived_key[i]);
}
chacha20poly1305_encrypt(dst, src, src_len, ad, ad_len,
h_nonce, (FAR uint8_t *)derived_key);
explicit_bzero(derived_key, CHACHA20POLY1305_KEY_SIZE);
}
int xchacha20poly1305_decrypt(
FAR uint8_t *dst,
FAR const uint8_t *src,
const size_t src_len,
FAR const uint8_t *ad,
const size_t ad_len,
FAR const uint8_t *nonce,
FAR const uint8_t *key)
{
int ret;
int i;
uint32_t derived_key[CHACHA20POLY1305_KEY_SIZE / sizeof(uint32_t)];
uint64_t h_nonce;
memcpy(&h_nonce, nonce + 16, sizeof(h_nonce));
h_nonce = le64toh(h_nonce);
hchacha20(derived_key, nonce, key);
for (i = 0; i < (sizeof(derived_key) / sizeof(derived_key[0])); i++)
{
derived_key[i] = htole32(derived_key[i]);
}
ret = chacha20poly1305_decrypt(dst, src, src_len, ad, ad_len,
h_nonce, (FAR uint8_t *)derived_key);
explicit_bzero(derived_key, CHACHA20POLY1305_KEY_SIZE);
return ret;
}
Reference in New Issue View Git Blame Copy Permalink