Kirin OS のファイル暗号化と復号化はプライバシーをどのように保護しますか?

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/evp.h>

void encrypt_file(const char *input_file, const char *output_file, const char *key) {
    EVP_CIPHER_CTX *ctx;
    FILE *input, *output;
    unsigned char inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH];
    int outlen, len, total = 0;

    // 初始化加密环境
    ctx = EVP_CIPHER_CTX_new();
    EVP_EncryptInit_ex(ctx, EVP_aes_256_cbc(), NULL, key, NULL);

    // 打开输入文件
    input = fopen(input_file, "rb");
    if (!input) {
        fprintf(stderr, "Failed to open input file: %s
", input_file);
        return;
    }

    // 打开输出文件
    output = fopen(output_file, "wb");
    if (!output) {
        fprintf(stderr, "Failed to open output file: %s
", output_file);
        fclose(input);
        return;
    }

    // 逐块加密数据
    while ((len = fread(inbuf, 1, sizeof(inbuf), input)) > 0) {
        EVP_EncryptUpdate(ctx, outbuf, &outlen, inbuf, len);
        fwrite(outbuf, 1, outlen, output);
        total += outlen;
    }

    // 结束加密过程
    EVP_EncryptFinal_ex(ctx, outbuf, &outlen);
    fwrite(outbuf, 1, outlen, output);
    total += outlen;

    // 清理工作
    fclose(input);
    fclose(output);
    EVP_CIPHER_CTX_free(ctx);

    printf("Encryption finished. Encrypted %d bytes.
", total);
}

int main() {
    const char *input_file = "plain.txt";
    const char *output_file = "encrypted.txt";
    const char *key = "abcdefghijklmnop";  // 16字节的密钥

    encrypt_file(input_file, output_file, key);

    return 0;
}

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/evp.h>

void decrypt_file(const char *input_file, const char *output_file, const char *key) {
    EVP_CIPHER_CTX *ctx;
    FILE *input, *output;
    unsigned char inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH];
    int outlen, len, total = 0;

    // 初始化解密环境
    ctx = EVP_CIPHER_CTX_new();
    EVP_DecryptInit_ex(ctx, EVP_aes_256_cbc(), NULL, key, NULL);

    // 打开输入文件
    input = fopen(input_file, "rb");
    if (!input) {
        fprintf(stderr, "Failed to open input file: %s
", input_file);
        return;
    }

    // 打开输出文件
    output = fopen(output_file, "wb");
    if (!output) {
        fprintf(stderr, "Failed to open output file: %s
", output_file);
        fclose(input);
        return;
    }

    // 逐块解密数据
    while ((len = fread(inbuf, 1, sizeof(inbuf), input)) > 0) {
        EVP_DecryptUpdate(ctx, outbuf, &outlen, inbuf, len);
        fwrite(outbuf, 1, outlen, output);
        total += outlen;
    }

    // 结束解密过程
    EVP_DecryptFinal_ex(ctx, outbuf, &outlen);
    fwrite(outbuf, 1, outlen, output);
    total += outlen;

    // 清理工作
    fclose(input);
    fclose(output);
    EVP_CIPHER_CTX_free(ctx);

    printf("Decryption finished. Decrypted %d bytes.
", total);
}

int main() {
    const char *input_file = "encrypted.txt";
    const char *output_file = "plain.txt";
    const char *key = "abcdefghijklmnop";  // 16字节的密钥

    decrypt_file(input_file, output_file, key);

    return 0;
}