This is how I have been generating my cryptographic keys until now:
这就是我到目前为止生成加密密钥的方法:
unsigned char *salt; //8 salt bytes were created earlier
unsigned char *password; //password was obtained earlier
int passwordLength; //password length as well
unsigned char evp_key[EVP_MAX_KEY_LENGTH] = {"\0"};
unsigned char iv[EVP_MAX_IV_LENGTH];
EVP_BytesToKey(cipher, EVP_md5(), salt, password, //cipher is also given
passwordLength,
1, evp_key, iv);
The result is a key and an “initial value.” I can then use these two (evp_key and iv) along with the given cipher to encrypt my data.
结果是一个键和一个“初始值”。然后我可以使用这两个(evp_key和iv)以及给定的密码来加密我的数据。
Now that with Lion, Apple has deprecated the above code, I have the following question:
现在,对于Lion,Apple已弃用上述代码,我有以下问题:
Question: How do I do the same thing with CommonCrypto? I just came across the CCKeyDerivationPBKDF() function. Is this the one I’m looking for? I can’t see how this is the case, since I don’t get any “initial value” back. I don’t know how to compare this CommonCrypto function with the old method.
问题:如何使用CommonCrypto执行相同的操作?我刚刚遇到了CCKeyDerivationPBKDF()函数。这是我正在寻找的那个吗?我看不出这是怎么回事,因为我没有得到任何“初始价值”。我不知道如何将这个CommonCrypto函数与旧方法进行比较。
In particular: This new function doesn’t seem to even support the MD5 algorithm—only the SHA1. How, then, can I create new code that is backwards compatible with my old codebase (and files it has created)?
特别是:这个新功能似乎甚至不支持MD5算法 - 只支持SHA1。那么,我如何创建与我的旧代码库(以及它创建的文件)向后兼容的新代码?
1 个解决方案
#1
1
I found the solution. To me, it seems impossible to derive the keys exactly the way OpenSSL does using any Apple’s methods. Instead, I just had to read how OpenSSL derive the key and initialization vector in the section “Key Derivation Algorithm” on the page http://www.openssl.org/docs/crypto/EVP_BytesToKey.html and simply mimic that.
我找到了解决方案。对我来说,似乎不可能完全按照OpenSSL使用任何Apple方法的方式导出密钥。相反,我只需要阅读OpenSSL如何在http://www.openssl.org/docs/crypto/EVP_BytesToKey.html页面的“密钥推导算法”部分中推导出密钥和初始化向量,并简单地模仿它。
#1
1
I found the solution. To me, it seems impossible to derive the keys exactly the way OpenSSL does using any Apple’s methods. Instead, I just had to read how OpenSSL derive the key and initialization vector in the section “Key Derivation Algorithm” on the page http://www.openssl.org/docs/crypto/EVP_BytesToKey.html and simply mimic that.
我找到了解决方案。对我来说,似乎不可能完全按照OpenSSL使用任何Apple方法的方式导出密钥。相反,我只需要阅读OpenSSL如何在http://www.openssl.org/docs/crypto/EVP_BytesToKey.html页面的“密钥推导算法”部分中推导出密钥和初始化向量,并简单地模仿它。