aes128 加解密的C语言实现

以下是AES128加解密的C语言实现，使用了OpenSSL库：

#include <openssl/aes.h>

int aes_encrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key) {
    AES_encrypt(in, out, key);
    return 0;
}

int aes_decrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key) {
    AES_decrypt(in, out, key);
    return 0;
}

其中，`AES_KEY`是OpenSSL库中定义的结构体，用于存储AES算法密钥。`aes_encrypt`和`aes_decrypt`分别为加密和解密函数，参数中的`in`和`out`分别为输入和输出的数据缓冲区，`key`为AES算法密钥。

使用此代码需要先安装OpenSSL库，并在代码中引入头文件`<openssl/aes.h>`。

相关问题

aes加解密c语言实现

AES是一种高级加密标准，它是一种对称加密算法，也就是说AES加密和解密使用的是同一套算法。下面是使用C语言实现AES加解密的示例代码（使用openssl库）：

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

#define AES_BLOCK_SIZE 16

int aes_encrypt(unsigned char *in, int in_len, unsigned char *key, unsigned char *out)
{
    AES_KEY aes_key;

    if (AES_set_encrypt_key(key, 128, &aes_key) < 0) {
        return -1;
    }

    int padding_len = AES_BLOCK_SIZE - (in_len % AES_BLOCK_SIZE);
    int total_len = in_len + padding_len;

    unsigned char *padded_in = malloc(total_len);
    if (!padded_in) {
        return -1;
    }
    memcpy(padded_in, in, in_len);
    memset(padded_in + in_len, padding_len, padding_len);

    for (int i = 0; i < total_len / AES_BLOCK_SIZE; i++) {
        AES_encrypt(padded_in + i * AES_BLOCK_SIZE, out + i * AES_BLOCK_SIZE, &aes_key);
    }

    free(padded_in);
    return total_len;
}

int aes_decrypt(unsigned char *in, int in_len, unsigned char *key, unsigned char *out)
{
    AES_KEY aes_key;

    if (AES_set_decrypt_key(key, 128, &aes_key) < 0) {
        return -1;
    }

    for (int i = 0; i < in_len / AES_BLOCK_SIZE; i++) {
        AES_decrypt(in + i * AES_BLOCK_SIZE, out + i * AES_BLOCK_SIZE, &aes_key);
    }

    int padding_len = out[in_len - 1];
    return in_len - padding_len;
}

int main()
{
    unsigned char key[16] = "0123456789abcdef";
    unsigned char in[] = "hello world";
    unsigned char out[256];

    int len = aes_encrypt(in, strlen(in), key, out);
    printf("encrypt: %s\n", out);

    int out_len = aes_decrypt(out, len, key, in);
    in[out_len] = '\0';
    printf("decrypt: %s\n", in);

    return 0;
}

注意，在加密时需要对输入进行padding，以保证长度是16的倍数。在解密时需要去除padding。

AES加密解密C语言实现

以下是AES加密解密的C语言实现：

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

// AES加密函数
int aes_encrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
{
    AES_set_encrypt_key(key->key, 128, key);
    AES_encrypt(in, out, key);
    return 0;
}

// AES解密函数
int aes_decrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
{
    AES_set_decrypt_key(key->key, 128, key);
    AES_decrypt(in, out, key);
    return 0;
}

int main()
{
    AES_KEY key;
    unsigned char *input_str = "Hello World!"; // 待加密的字符串
    unsigned char *encrypt_str = (unsigned char *)malloc(strlen(input_str) + 1); // 存储加密后的字符串
    unsigned char *decrypt_str = (unsigned char *)malloc(strlen(input_str) + 1); // 存储解密后的字符串

    // 设置密钥
    unsigned char *key_str = "1234567890123456";
    AES_set_encrypt_key(key_str, 128, &key);

    // 加密
    aes_encrypt(input_str, encrypt_str, &key);
    printf("加密后的字符串：%s\n", encrypt_str);

    // 解密
    aes_decrypt(encrypt_str, decrypt_str, &key);
    printf("解密后的字符串：%s\n", decrypt_str);

    free(encrypt_str);
    free(decrypt_str);
    return 0;
}