基于Openssl的aes_128_ecb的pkcs5padding加密解密文本

  网上有一堆关于openssl的aes的加密方式,搞得都痛死了,pkcs5padding的补码方式的代码确少之又少,终于在我不懈努力下搞定这玩意了,代码是C++的

CAES.h文件

#pragma once
#include <openssl/aes.h>
#include <string>
class CAES
{
public:

	static std::string aes_128_ecb_encrypt(const std::string& source, const std::string& key);
	static std::string aes_128_ecb_decrypt(const std::string& ciphertext, const std::string& key);
};

CAES.cpp文件

#include "stdafx.h"
#include "AES.h"
#include <openssl/evp.h>
#include <openssl/ssl.h>
#include "Base64.h"
#include <cassert>

struct evp_cipher_ctx_st {
	const EVP_CIPHER *cipher;
	ENGINE *engine;             /* functional reference if 'cipher' is
								* ENGINE-provided */
	int encrypt;                /* encrypt or decrypt */
	int buf_len;                /* number we have left */
	unsigned char oiv[EVP_MAX_IV_LENGTH]; /* original iv */
	unsigned char iv[EVP_MAX_IV_LENGTH]; /* working iv */
	unsigned char buf[EVP_MAX_BLOCK_LENGTH]; /* saved partial block */
	int num;                    /* used by cfb/ofb/ctr mode */
	void *app_data;             /* application stuff */
	int key_len;                /* May change for variable length cipher */
	unsigned long flags;        /* Various flags */
	void *cipher_data;          /* per EVP data */
	int final_used;
	int block_mask;
	unsigned char final[EVP_MAX_BLOCK_LENGTH]; /* possible final block */
}; /* EVP_CIPHER_CTX */

/*
 * openssl aes 128 ecb pkcs5padding 加密
 */
std::string CAES::aes_128_ecb_encrypt(const std::string& source, const std::string& key)
{
	EVP_CIPHER_CTX *ctx;
	ctx = EVP_CIPHER_CTX_new();
	int ret = EVP_EncryptInit_ex(ctx, EVP_aes_128_ecb(), NULL, (const unsigned char*)key.data(), NULL);
	assert(ret == 1);
	unsigned char* result = new unsigned char[source.length() + 64]; // 弄个足够大的空间
	int len1 = 0;
	ret = EVP_EncryptUpdate(ctx, result, &len1, (const unsigned char*)source.data(), source.length());
	assert(ret == 1);
	int len2 = 0;
	ret = EVP_EncryptFinal_ex(ctx, result + len1, &len2);
	assert(ret == 1);
	ret = EVP_CIPHER_CTX_cleanup(ctx);
	assert(ret == 1);
	EVP_CIPHER_CTX_free(ctx);
	std::string res((char*)result, len1 + len2);
	delete[] result;
	return res;
}
/*
 * openssl aes 128 ecb pkcs5padding 解密
 */
std::string CAES::aes_128_ecb_decrypt(const std::string& ciphertext, const std::string& key)
{
	EVP_CIPHER_CTX *ctx;
	ctx = EVP_CIPHER_CTX_new();
	int ret = EVP_DecryptInit_ex(ctx, EVP_aes_128_ecb(), NULL, (const unsigned char*)key.data(), NULL);
	assert(ret == 1);
	unsigned char* result = new unsigned char[ciphertext.length() + 64]; // 弄个足够大的空间
	int len1 = 0;
	ret = EVP_DecryptUpdate(ctx, result, &len1, (const unsigned char*)ciphertext.data(), ciphertext.length());
	assert(ret == 1);
	int len2 = 0;
	ret = EVP_DecryptFinal_ex(ctx, result + len1, &len2);
	assert(ret == 1);
	ret = EVP_CIPHER_CTX_cleanup(ctx);
	assert(ret == 1);
	EVP_CIPHER_CTX_free(ctx);
	std::string res((char*)result, len1 + len2);
	delete[] result;
	return res;
}

最后就是main函数了

  #include "stdafx.h"
  #include <string>
  #include <iostream>
  #include "AES.h"
  #include <openssl/aes.h>  
 
int main()
{
	std::string aes_key("helloaeshelloaes", 16);
	std::string soure = "Hello World!!";
	std::string encrypt = CAES::aes_128_ecb_encrypt(soure, aes_key);
	//std::cout << "AES加密:" + encrypt << std::endl;
	std::string decrypt = CAES::aes_128_ecb_decrypt(encrypt, aes_key);
	std::cout << "AES解密:" + decrypt << std::endl;
	system("pause");
	return 0;
}

注释的这一行控制台没办法base46的字符串出来,需要将base64转成可识别的字符串类型,就能正常的输出了,后面我会将Base64转string的代码放出来