OpenSSL AES256 cbc 加密

Question

几天来我试图在互联网上找到合适的例子，但没有成功。我尝试用密钥加密简单的字符串（Hello World），然后解密结果。 但解密结果与原文无关。有人能给我指个方向吗？

我制作的代码：

AES_KEY aes_decryptKey;
AES_KEY aes_encryptKey;

const unsigned char mykey[] = {0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa};
unsigned char encrypted ;
unsigned char iv[] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};    
unsigned char decrypted;

AES_set_encrypt_key(mykey, 256, &aes_encryptKey);
AES_set_decrypt_key(mykey, 256, &aes_decryptKey);

const unsigned char original[]  = {0x48,0x65,0x6c,0x6c,0x6f,0x2c,0x77,0x6f,0x72,0x6c,0x64,0x21};

AES_cbc_encrypt(original, &encrypted, sizeof(original), &aes_encryptKey, iv, 0);

AES_decrypt( &encrypted, &decrypted, &aes_decryptKey);

NSLog(@"ORIGINAL: \"%s\"\n",original);
NSLog(@"ENCRYPTED: \"%s\"\n",&encrypted);
NSLog(@"DECRYPTED: \"%s\"\n",&decrypted);

Answer 1

您正在解密两次 - AES_cbc_encrypt 的最后一个 0 参数应该是 1 或 AES_ENCRYPT。

此外，您正在覆盖您的加密和解密字符，这些字符应该是足够大的数组来容纳原始的加密大小。而不是：

unsigned char encrypted;
...
AES_cbc_encrypt(original, &encrypted, ...

使用类似：

unsigned char encrypted[32];
...
AES_cbc_encrypt(original, encrypted, ...

也类似：

unsigned char decrypted[32];
....
AES_decrypt(encrypted, decrypted, &aes_decryptKey);

查看此链接： http:// /marc.info/?l=openssl-users&m=122919878204439。我还不能保证这一切——等我有时间的时候我会回来编辑我的答案。

Answer 2

吉姆，谢谢你的帮助。

看来我必须提出问题才能找到答案。
经过很多天的努力，这就是我想出的结果：

    unsigned char inbuf[1024]="Hello,world!";
unsigned char encbuf[1024];

unsigned char key32[] = {0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa};
unsigned char deckey32[] = {0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa,0xaa}
;
unsigned char iv[] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};    
unsigned char deciv[] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};    

AES_KEY aeskey;
AES_KEY aesdeckey;

//Now enrypt
memset(encbuf, 0, sizeof(encbuf));
AES_set_encrypt_key(key32, 32*8, &aeskey);
AES_cbc_encrypt(inbuf, encbuf, 16, &aeskey, iv, AES_ENCRYPT);

//Now decrypt
unsigned char decbuf[1024];
memset(decbuf, 0, sizeof(decbuf));

AES_set_decrypt_key(deckey32, 32*8, &aesdeckey);
AES_cbc_encrypt(encbuf, decbuf, 16, &aesdeckey, deciv, AES_DECRYPT);


//Display the results
NSLog(@"ORIGINAL: \"%s\"\n", inbuf);
NSLog(@"ENCRYPTED: \"%s\"\n", encbuf);
NSLog(@"DECRYPTED: \"%s\"\n", decbuf);

return;

感谢这些人（在吉姆之后）：http://www.mail-archive.com/[email protected]/msg50142.html

关键是使用 AES_cbc_encrypt 进行解密。