mirror of
https://github.com/espressif/ESP8266_RTOS_SDK.git
synced 2025-05-22 17:47:04 +08:00
92 lines
2.0 KiB
C
92 lines
2.0 KiB
C
// Copyright 2018-2019 Espressif Systems (Shanghai) PTE LTD
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
#include <sys/errno.h>
|
|
#include <string.h>
|
|
#include "esp_arc4.h"
|
|
#include "ibus_data.h"
|
|
#include "util_assert.h"
|
|
|
|
/*
|
|
* ARC4 key schedule
|
|
*/
|
|
void esp_arc4_setup(esp_arc4_context *ctx, const uint8_t *key, uint32_t keylen)
|
|
{
|
|
int i, j, a;
|
|
uint32_t k;
|
|
uint8_t *m;
|
|
|
|
util_assert(ctx);
|
|
util_assert(key);
|
|
|
|
ctx->x = 0;
|
|
ctx->y = 0;
|
|
m = ctx->m;
|
|
|
|
for(i = 0; i < 256; i++)
|
|
m[i] = (uint8_t) i;
|
|
|
|
j = k = 0;
|
|
|
|
for(i = 0; i < 256; i++, k++)
|
|
{
|
|
if(k >= keylen) k = 0;
|
|
|
|
a = m[i];
|
|
j = (j + a + key[k]) & 0xFF;
|
|
m[i] = m[j];
|
|
m[j] = (uint8_t) a;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ARC4 cipher function
|
|
*/
|
|
int esp_arc4_encrypt(esp_arc4_context *ctx, size_t length, const uint8_t *input, uint8_t *output)
|
|
{
|
|
int x, y, a, b;
|
|
size_t i;
|
|
uint8_t *m;
|
|
|
|
util_assert(ctx);
|
|
util_assert(input);
|
|
util_assert(output);
|
|
|
|
x = ctx->x;
|
|
y = ctx->y;
|
|
m = ctx->m;
|
|
|
|
for(i = 0; i < length; i++)
|
|
{
|
|
x = (x + 1) & 0xFF; a = m[x];
|
|
y = (y + a) & 0xFF; b = m[y];
|
|
|
|
m[x] = (uint8_t) b;
|
|
m[y] = (uint8_t) a;
|
|
|
|
output[i] = (uint8_t)(input[i] ^ m[(uint8_t)(a + b)]);
|
|
}
|
|
|
|
ctx->x = x;
|
|
ctx->y = y;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int esp_arc4_decrypt(esp_arc4_context *ctx, size_t length, const uint8_t *input, uint8_t *output)
|
|
{
|
|
return esp_arc4_encrypt(ctx, length, input, output);
|
|
}
|
|
|