我有一对夫妇在使用密码的问题。 我使用AES
问题1：
我试图使用SecretKeyFactory类英寸 我想获得实例相关PBKDF1 PKCS＃5。 我是新来加密。 我试着在网上，但荫无法找到任何这样的算法。 是否支持它。 我想这样的一些东西。
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF1Pkcs#5");
KeySpec spec = new PBEKeySpec(password, salt, 1, 128);
问题2：
是否上面的代码两行做同样的事情，如在以下行代码在C + +
::PKCS5_PBKDF1 <::MD5> fn;
fn.DeriveKey(key, CRYPTO::MD5::DIGESTSIZE, 0, key.getBytes(), salt.getBytes(), salt.size(), PBKDF1_ITERATIONS,time_in_seconds);
如果没有能有人给一些东西可以模仿什么的C ++代码上面的纹路做。
谢谢
Re: Question 1
Per the Java 6 API docs for SecretKeyFactory,
Application developers should refer to their provider's documentation to find out which key specifications are supported by the generateSecret and getKeySpec methods. For example, the DES secret-key factory supplied by the "SunJCE" provider supports DESKeySpec as a transparent representation of DES keys, and that provider's secret-key factory for Triple DES keys supports DESedeKeySpec as a transparent representation of Triple DES keys.
If we look at the SunJCE provider documentation for PKCS, we see...
PBEWithMD5AndDES: The password-based encryption algorithm as defined in: RSA Laboratories, "PKCS #5: Password-Based Encryption Standard," version 1.5, Nov 1993. Note that this algorithm implies CBC as the cipher mode and PKCS5Padding as the padding scheme and cannot be used with any other cipher modes or padding schemes.
Re: Question 2
In the same document, in the section Using Password-Based Encryption, you will find the following sample code. Keep in mind that the sample code uses a static salt, but a secure implementation would use generate a random salt each time the user changes their password.
PBEKeySpec pbeKeySpec;
PBEParameterSpec pbeParamSpec;
SecretKeyFactory keyFac;
// Salt
byte[] salt = {
(byte)0xc7, (byte)0x73, (byte)0x21, (byte)0x8c,
(byte)0x7e, (byte)0xc8, (byte)0xee, (byte)0x99
};
// Iteration count
int count = 20;
// Create PBE parameter set
pbeParamSpec = new PBEParameterSpec(salt, count);
// Prompt user for encryption password.
// Collect user password as char array (using the
// "readPasswd" method from above), and convert
// it into a SecretKey object, using a PBE key
// factory.
System.out.print("Enter encryption password: ");
System.out.flush();
pbeKeySpec = new PBEKeySpec(readPasswd(System.in));
keyFac = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey pbeKey = keyFac.generateSecret(pbeKeySpec);
// Create PBE Cipher
Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
// Initialize PBE Cipher with key and parameters
pbeCipher.init(Cipher.ENCRYPT_MODE, pbeKey, pbeParamSpec);
// Our cleartext
byte[] cleartext = "This is another example".getBytes();
// Encrypt the cleartext
byte[] ciphertext = pbeCipher.doFinal(cleartext);
Other Algorithms
Again, from the same page. Really, I recommend you read through the whole thing, as it will probably answer other questions you have, as well
PBEWith<digest>And<encryption> or PBEWith<prf>And<encryption>: Secret-key factory for use with PKCS #5 password-based encryption, where <digest> is a message digest, <prf> is a pseudo-random function, and <encryption> is an encryption algorithm. Examples: PBEWithMD5AndDES (PKCS #5, v 1.5) and PBEWithHmacSHA1AndDESede (PKCS #5, v 2.0). Note: These both use only the low order 8 bits of each password character.
