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Emulate php openssl_decrypt function in Java with hardcoded key

I need to replicate functionality in java, NOT IMPROVE PHP code.
Php 7 code:
openssl_encrypt("123::secret", "aes-256-cbc", "1234567899999999", 0, "0123456789999999");
// VZq5nLyJaAzajWQqMMLgmQ==
openssl_decrypt("VZq5nLyJaAzajWQqMMLgmQ==", "aes-256-cbc", "1234567899999999", 0, "0123456789999999");
// 123::secret
In Java, I want to make the same, so PHP would be able to decrypt it
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec("1234567899999999".getBytes(), "AES"), new IvParameterSpec("0123456789999999".getBytes()));
byte[] res = cipher.doFinal("123::secret".getBytes());
java.util.Base64.getEncoder().encodeToString(res);
// xIwXN6R+X/FMMqfmsYhEQQ==
But, this key is different and PHP returns false on decrypt attempt. I find many solutions, but they around generating random 256 key lengths, but in my situation PHP code is using hardcoded secret

Topaca's answer is correct (php code can not be changed). To fully emulate described PHP function with provided arguments, need to update the password with "\0" to meet the length requirement

RSA encryption in Java, decrypt in PHP

Assume I have the following Java code to generate a Public-private keypair:
KeyPairGenerator generator = KeyPairGenerator.getInstance ("RSA");
SecureRandom random = SecureRandom.getInstance("SHA1PRNG");
generator.initialize (1024, random);
KeyPair pair = generator.generateKeyPair();
RSAPrivateKey priv = (RSAPrivateKey)pair.getPrivate();
RSAPublicKey pub = (RSAPublicKey)pair.getPublic();
// Sign a message
Signature dsa = Signature.getInstance("SHA1withRSA");
dsa.initSign (priv);
dsa.update ("Hello, World".getBytes(), 0, "Hello, World".length());
byte[] out = dsa.sign();
/* save the signature in a file */
FileOutputStream sigfos = new FileOutputStream("sig");
sigfos.write(out);
sigfos.close();
How would one go about and decrypt the file "sig" in PHP? I've read the post: https://stackoverflow.com/a/1662887/414414 which supplies a function to convert a DER file to PEM (Assume I also save the public key from Java).
I have tried something like:
$key = openssl_pkey_get_public ("file://pub_key.pem");
$data = null;
openssl_public_decrypt ( file_get_contents ("sig"), $data, $key);
echo $data, "\n";
It successfully decrypts the message, but it is many weird characters.
Our scenario is a Java client that is sending messages to a PHP server, but encrypts the data with a private key. PHP knows about the public key, which it should use to decrypt and validate the message.
I've read a lot of posts regarding this issue here on SO, but I've come to realize that this is a bit specific issue, especially if there's different algorithms in use, etc. So sorry if this may be a duplicate.
Any feedbacks are greatly appreciated!

an "RSA signature" is usually more than just "encrypt with private key, decrypt with public key", since Public key protocols like PKCS#1 also specify padding schemes, and all signature schemes will encrypt a digest of the message, instead of the full message. I cannot find any documentation if java's signature scheme uses the signature padding scheme specified in PKCS#1, but my suspicion is that it is.
If it is, you will instead want to use the openssl_verify method in PHP, documented here. This will return a 0 or 1 if the signature is invalid or valid, respectively.
In the event that Java does not use a padding scheme, your issue is that the data encrypted in the signature is a hash of the message, instead of the message itself (you can see in the Java code that it uses the SHA-1 hash algorithm). So on the PHP side, you will need to take the sha1 hash of your message using the sha1 method with $raw_output set to true, and compare those strings to ensure your message is valid.

From the snippet
$key = openssl_pkey_get_public ("file://pub_key.pem");
It looks like you're referencing the public key, which would be the wrong one to decrypt. Double check ?

MessageDigest MD5 Algorithm not returning what I expect

Something in the back of my head is telling me I'm missing something obvious here.
I'm integrating an existing java project with a third-party api that uses an md5 hash of an api key for authentication. It's not working for me, and during debugging I realized that the hashes I'm generating don't match the examples that they've supplied. I've found some websites that create MD5 hashes from strings to check their examples, and as far as I can tell I'm wrong and they're right.
for example, according to this website, the string "hello" generates a hash of "5d41402abc4b2a76b9719d911017c592". (FWIW I don't know anything about this website except that it seems to correctly hash the examples that I have). When I run it through my code I get:
XUFAKrxLKna5cZ2REBfFkg==
Here is the simple method I'm using to generate the md5 hash/string.:
private String md5(String md5Me) throws Exception {
MessageDigest md = MessageDigest.getInstance("MD5");
md.reset();
md.update(md5Me.getBytes("UTF-8"));
return Base64.encodeBase64String(md.digest());
}
I used a very similar method to successfully authenticate a different API using the SHA1 algorithm last week. I'm wondering if the problem is related to the org.apache.commons.net.util.Base64.encodeBase64String... Any help is greatly appreciated, if only some tests to see if the byteArray is correct but the converted string is wrong.

for example, according to this website, the string "hello" generates a hash of "5d41402abc4b2a76b9719d911017c592". (FWIW I don't know anything about this website except that it seems to correctly hash the examples that I have). When I run it through my code I get:
XUFAKrxLKna5cZ2REBfFkg==
Both are correct ways of representing the same sixteen-byte hash. 5d41402abc4b2a76b9719d911017c592 represents each byte of the hash as two hexadecimal digits, whereas XUFAKrxLKna5cZ2REBfFkg== uses Base-64 to represent every three bytes of the hash as four characters.
To generate the hexadecimal-version that this third-party API is expecting, you can change this:
Base64.encodeBase64String(md.digest());
to this:
String.format("%032x", new BigInteger(1, md.digest()));
(mostly taken from this StackOverflow answer).
However, you might want to consider using an external library for this. Perception, in a comment above, mentions Apache Commons DigestUtils. If you use that, you'll want the md5hex method.

The md5 Hash algorithm is part of the core java API so there is no need for any external libraries. Here is the method I used to encrypt a password with MD5.
import java.security.MessageDigest;
/**
* Use to encrypt passwords using MD5 algorithm
* #param password should be a plain text password.
* #return a hex String that results from encrypting the given password.
*/
public static String encryptPassword(String password) {
try {
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(password.getBytes());
byte byteData[] = md.digest();
StringBuffer hexString = new StringBuffer();
for (int i=0;i<byteData.length;i++) {
String hex=Integer.toHexString(0xff & byteData[i]);
if(hex.length()==1) hexString.append('0');
hexString.append(hex);
}
return hexString.toString();
}
catch(java.security.NoSuchAlgorithmException missing) {
return "Error.";
}
}

Equivalent of PHP's crypt function in Java

I am migrating my PHP code to Google App Engine - Java.
So I need an equivalent of PHP's crypt function in Java,
since I have stored all the passwords of registered users
using crypt in my DB.
Edit 1:
Here is my php code for encrypting passwords :
$password = "test123";
$pwd = crypt($password,$password);
echo $pwd;
Output is (On Windows as well as a linux based server on HostMonser):
temjCCsjBECmU
Can someone give me equivalted java code?
I have tried various permutations & combinations with
MessageDigest class, but can't get it right..
Edit 2:
Here is sample code which I thought would work but did not:
try {
{
String password = "test123";
MessageDigest digest = MessageDigest.getInstance( "MD5" );
byte[] passwordBytes = password.getBytes( );
digest.reset( );
digest.update( passwordBytes );
digest.update( passwordBytes );
byte[] message = digest.digest( );
StringBuffer hexString = new StringBuffer();
for ( int i=0; i < message.length; i++)
{
hexString.append( Integer.toHexString(
0xFF & message[ i ] ) );
}
String encrypted = hexString.toString();
System.out.println(encrypted);
} } catch (NoSuchAlgorithmException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}

This is an old thread but I ran into the same issue and found a different solution. You can use the UnixCrypt/Md5Crypt classes in the Apache Commons Codec 1.7 library.
For example you can call
UnixCrypt.crypt(string, salt)
OR
Md5Crypt.md5Crypt(byte[], salt)
I haven't looked into the other encryption types but I imagine their are other utilities as well.
org.apache.commons.codec.digest.UnixCrypt
org.apache.commons.codec.digest.Md5Crypt

You have to know what implementation of PHP crypt has been used (MD5? SHA256? SHA512?) because there are several, depending on your OS : http://php.net/manual/fr/function.crypt.php
The Java equivalent class is MessageDigest. When you create an instance of this class, you provide the hash algorithm, for example :
MessageDigest md = MessageDigest.getInstance("MD5");
MessageDigest md2 = MessageDigest.getInstance("SHA-256");
MessageDigest md3 = MessageDigest.getInstance("SHA-512");
// etc.
byte[] encryptedPassword = md.digest("yourPassword".getBytes());

It seems you have to work with a legacy database already populated with passwords you cannot discard, so you can't just switch to a salted MessageDigest, preferably using SHA-1. And your problem gets more complicated, since PHP's crypt is a wrapper that might use one of several algorithms. But let's assume your PHP uses the original DES-based UNIX crypt, then all you need is an implementation of that in Java. As far as i know, there is no implementation of UNIX's crypt in the standard Java installation, but you might want to look here for a list of options.

You need to take a look at the java.security classes (what used to tbe the JCE):
In there you'll find everything you need to do what you want (depending on which algorithm you need).
http://download.oracle.com/docs/cd/E17409_01/javase/6/docs/api/java/security/package-summary.html
e.g. MessageDigest for MD5/SHA etc:
http://download.oracle.com/docs/cd/E17409_01/javase/6/docs/api/java/security/MessageDigest.html
Check these against the Google App Engine whitelist here, I'm not sure what's supported and what isn't.
http://code.google.com/appengine/docs/java/jrewhitelist.html
The java.security stuff can be a bit of a pain to work with sometimes, you may alternatively want to use Jasypt - which is a more simplified API that works with any JCE:
http://www.jasypt.org/

PHP's crypt supports multiple hash functions. If you use the MD5 version (hash starts with $1$), you can find a Java implementation here,
http://www.java2s.com/Open-Source/Java-Document/Groupware/LibreSource/md5/MD5Crypt.java.htm
Please notice that they use their own MD5 class. I am not sure if it's the same as standard MD5.
I am sure you can find Java implementation for other hash algorithms too.

Well, PHP's crypt isn't actually encryption as far as I know. It's just a wrapper around some one-way hashing functions I believe, so if your current PHP site's using crypt's MD5 or SHA256 or whatever, I'd expect that you could find those equivalent hashing classes/functions in Java.

I can recommend this: MD5Crypt implementation
MD5Crypt.crypt("youPassword"); // output: $1$zSiw0koU$i3Srfmoxx4VPePJHWqAuK/
This is one of the few implementations, which works for me.

PKI verification across Java and Python

I am trying to implement a PKI verification scheme, where a message string is signed with a private key on server, the signature is stored on the client along with the message string. The client then verifies the signature using a public key.
The restrictions of my environment are, the server is Google App Engine and the client is a Java program. I have played with Java-only and Python-only solutions of PKI verification and got them to work, however when doing one operation in Python and another in Java is posing problem, mainly due to Key file format restrictions and my limited understanding of cryptography terminology.
One of the biggest limitations is crypto support in GAE. The only library supported is PyCrypto and this library can't read public/private keys stored in PEM, DER or X509 formats. As far as I could find, only M2Crypto supports reading from these files, but it can't be used inside GAE because it's a wrapper around openssl, so not a pure python solution. Even if I could find a way to translate the public/private keys from PEM/DER/X509 to the format that PyCrypto understands, that will work for me. But I couldn't find any way to do it. Any ideas there?
I found one possible solution in the form of tlslite. tlslite could read a private key from PEM file and create a signature. Here is the code.
from tlslite.utils.cryptomath import bytesToBase64
from tlslite.utils.keyfactory import parsePEMKey
s = open('private.pem').read()
key = parsePEMKey(s)
doc = 'Sample text'
bytes = array('B')
bytes.fromstring(doc)
print bytesToBase64(key.sign(bytes))
The corresponding Java code I used to verify the signature is.
String signAlgo = "SHA1WithRSAEncryption";
// read public key from public.der
byte[] encodedKey = new byte[294]; // shortcut hardcoding
getAssets().open("public.der").read(encodedKey);
// create public key object
X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(encodedKey);
KeyFactory kf = KeyFactory.getInstance("RSA");
PublicKey pk = kf.generatePublic(publicKeySpec);
// read signature (created by python code above)
byte[] encodedSig = new byte[345];
getAssets().open("signature.txt").read(encodedSig);
byte[] decodedSig = Base64.decodeBase64(encodedSig);
// Do verification
Signature verifyalg = Signature.getInstance(signAlgo);
verifyalg.initVerify(pk);
verifyalg.update(message.getBytes());
Log.d(TAG, "Verif : "+verifyalg.verify(decodedSig));
The verification fails.
I suspected if the tlslite is using different algorithm for signature creation than what the java code expects.
So I tried to find that out.
On python side
print key.getSigningAlgorithm()
gave me
pkcs1-sha1
on Java side, I tried to find all supported algorithms with this code:
Set<String> algos = java.security.Security.getAlgorithms("Signature");
for(String algo : algos) {
Log.d(TAG, algo);
}
That gave me
MD4WithRSAEncryption
RSASSA-PSS
SHA1withDSA
SHA1withRSA/ISO9796-2
1.2.840.113549.1.1.10
SHA512withRSA/PSS
MD5withRSA/ISO9796-2
DSA
SHA512WithRSAEncryption
SHA224withRSA/PSS
NONEWITHDSA
SHA256withRSA/PSS
SHA224WithRSAEncryption
SHA256WithRSAEncryption
SHA1withRSA/PSS
SHA1WithRSAEncryption
SHA384withRSA/PSS
SHA384WithRSAEncryption
MD5WithRSAEncryption
I tried all the SHA1 values on the Java side. But none helped to verify the signature generated by tlslite with pkcs1-sha1 algo. Any idea about this mapping?

These are different operations. In Python, you need to use hashAndSign. The default happens to be SHA1 hash.

Keyczar should work fine on App Engine, and is available in both Java and Python flavours.