PHP RSA Enryption Always Returns "AAAAAAA" - php

I'm trying to encrypt a message using phpseclib. Below is the method that encrypts it:
function RSAEncrypt($data, $publicKey)
{
$rsa = new \Crypt_RSA();
$rsa->loadKey($publicKey);
$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_PKCS1);
$encryptedData = $rsa->encrypt($data);
$encodedData = base64_encode($encryptedData);
return $encodedData;
}
the code that encrypt message
$client_key = 123456789;
$random_str = rand();
$aes_password = $client_key.'-'.$random_str;
$public_key = file_get_contents('keys/public.xml');
$ecrypted_password = RSAEncrypt($aes_password, $public_key);
but no matter the message the $aes_password that i passed , the $ecrypted_password output is always
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAE= ◀"
I tried to decrypt it using the private key to see if its valid anyways but i always gets Decryption Error so i figured maybe the error is with the encryption

Related

Decrypt AES-128 CBC - PHP

I have an encrypted message in AES-128 CBC in this format "f21fcc6677c9ba2335da551fa143cf08" and I'm trying to decrypt using a key in this format "cdff8db86efb418a8e492a29dba44869", I'm new to this and I can't seem to make it work, I tried this code with no success.
<?php
$simple_string = base64_decode('f21fcc6677c9ba2335da551fa143cf08');
echo $simple_string. "\n";
//echo $simple_string;
$ciphering = 'AES-128-CBC';
$iv_length = openssl_cipher_iv_length($ciphering);
$options = 0;
$encryption_key = 'cdff8db86efb418a8e492a29dba44869';
echo $encryption_key. "\n";
$decryption = openssl_decrypt($simple_string, $ciphering, $encryption_key, OPENSSL_RAW_DATA);
var_dump($decryption);
my output is
bool(false)
any ideas? I think I have to change the format of the encrypted message or the key, but don't find much in Google.

Gnupg doesn't decrypt the file in php

I try to decrypt my enrypted file(zip archive which contains multiple files) with Gnupg in php, but it constantly returns false. no exception or error message.
here's encryption:
$gpg = gnupg_init();
gnupg_seterrormode($gpg, GNUPG_ERROR_EXCEPTION);
// public key
$publicKey = file_get_contents('pubkey.pub');
$key = gnupg_import($gpg, $publicKey);
gnupg_addencryptkey($gpg, $key['fingerprint']);
// zip file
$zip = file_get_contents('myzip.zip');
$encryptedFile = gnupg_encrypt($gpg, $zip);
//save encrypted file
file_put_contents('myzip.zip.gpg', $encryptedFile);
here's decryption:
$gpg = gnupg_init();
$privateKey = file_get_contents('private.asc');
$key = gnupg_import($gpg, $privateKey);
gnupg_adddecryptkey($gpg, $key['fingerprint'], '12345');
$file = file_get_contents('myzip.zip.gpg');
$content = gnupg_decrypt($gpg, $file); // <- always returns false
I tried to decrypt the file with online tool. at first I tried to decrypt only 1 text file and it worked(it displayed the content of file). I tried to decrypt the zip archive as well
but everytime I try to decrypt it with gnupg_decrypt in php it return false. what am I doing wrong?
The problem was in gnupg version. I instilled gpg2 and it worked.

Is it Possible to migrate from PEAR Crypt to PHPSecLib RSA?

We migrated to PHPSecLib a while ago, but did not migrate our legacy data that was encrypted by the old PEAR\Crypt_RSA library. We've reached a point where we need to migrate that data into PHPSecLib's RSA format. While investigating this, I came across this old forum thread. I attempted to apply the suggestion in the response, but could not get it to successfully decrypt our data. It's not erroring out or anything, it just appears to still be encrypted or encoded. We're running PHPSecLib 2.0.6 currently, and I suspect the instructions were for 1.x.
Here's a roughed out version of my adapted decryption flow (based off the forum thread):
$rsaDecryptor = new RSA();
// The Private Key is encrypted based off a password
$mc = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_ECB, '');
$iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($mc), MCRYPT_DEV_URANDOM);
$keySize = mcrypt_enc_get_key_size($mc);
$key = substr($rsaDecryptor->password, 0, $keySize);
mcrypt_generic_init($mc, $key, $iv);
$privateKey = mdecrypt_generic($mc, base64_decode($privateKey));
mcrypt_generic_deinit($mc);
mcrypt_module_close($mc);
list($privateKeyModulus, $privateKeyExponent) = unserialize(base64_decode($privateKey));
$privateKeyExponent = new BigInteger(strrev($privateKeyExponent), 256);
$privateKeyModulus = new BigInteger(strrev($privateKeyModulus), 256);
$rsaDecryptor->modulus = $privateKeyModulus;
$rsaDecryptor->exponent = $privateKeyExponent;
$rsaDecryptor->publicExponent = $privateKeyExponent;
$rsaDecryptor->k = strlen($this->decRSA->modulus->toBytes());
// ciphertext is the raw encrypted string created by PEAR\Crypt_RSA
$value = base64_decode($ciphertext);
$value = new BigInteger($value, 256);
$value = $rsaDecryptor->_exponentiate($value)->toBytes();
$value = substr($value, 1);
Bugs In PEAR's Crypt_RSA
So I was playing around with this. There's a bug in PEAR's Crypt_RSA (latest version) that might prevent this from working at all. The following code demonstrates:
$key_pair = new Crypt_RSA_KeyPair(1024);
$privkey = $key_pair->getPrivateKey();
$pubkey = $key_pair->getPublicKey();
$a = $privkey->toString();
$b = $pubkey->toString();
echo $a == $b ? 'same' : 'different';
You'd expect $a and $b to be different, wouldn't you? Well they're not. This is because RSA/KeyPair.php does this:
$this->_public_key = &$obj;
...
$this->_private_key = &$obj;
If you remove the ampersands it works correctly but they're in the code by default.
It looks like this is an unresolved issue as of https://pear.php.net/bugs/bug.php?id=15900
Maybe it behaves differently on PHP4 but I have no idea.
Decrypting Data
Assuming the above bug isn't an issue for you then the following worked for me (using phpseclib 2.0):
function loadKey($key) // for keys genereated with $key->toString() vs $key->toPEMString()
{
if (!($key = base64_decode($key))) {
return false;
}
if (!($key = unserialize($key))) {
return false;
}
list($modulus, $exponent) = $key;
$modulus = new BigInteger(strrev($modulus), 256);
$exponent = new BigInteger(strrev($exponent), 256);
$rsa = new RSA();
$rsa->loadKey(compact('modulus', 'exponent'));
return $rsa;
}
function decrypt($key, $ciphertext)
{
if (!($ciphertext = base64_decode($ciphertext))) {
return false;
}
$key->setEncryptionMode(RSA::ENCRYPTION_NONE);
$ciphertext = strrev($ciphertext);
$plaintext = $key->decrypt($ciphertext);
$plaintext = strrev($plaintext);
$plaintext = substr($plaintext, 0, strpos($plaintext, "\0"));
return $plaintext[strlen($plaintext) - 1] == "\1" ?
substr($plaintext, 0, -1) : false;
}
$key = loadKey($private_key);
$plaintext = decrypt($key, $ciphertext);
echo $plaintext;
Private Keys Generated with toPEMString()
With PEAR's Crypt_RSA you can generate private keys an alternative way:
$key_pair->toPEMString();
This method works without code changes. If you used this approach to generate your private keys the private key starts off with -----BEGIN RSA PRIVATE KEY-----. If this is the case then you don't need to use the loadKey function I wrote. You can do this instead:
$key = new RSA();
$key->loadKey('...');
$plaintext = decrypt($key, $ciphertext);
echo $plaintext;

encrypt/decrypt with Android and PHP

Sorry for this question. I've read all the previous questions, but my code still not work.
Thanks in advance to anyone that will help me in understanding where is the problem.
In android I use this code for reading the public key and produce the encrypted text:
public static PublicKey getPublicKeyFromString(String stringKey) throws Exception {
byte[] keyBytes = stringKey.getBytes();
byte[] decode = Base64.decode(keyBytes, Base64.DEFAULT);
KeyFactory fact = KeyFactory.getInstance("RSA");
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(decode);
return (PublicKey) fact.generatePublic(x509KeySpec);
}
public static String RSAEncrypt(final String plain, final PublicKey publicKey)
throws NoSuchAlgorithmException, NoSuchPaddingException,
InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
byte[] encryptedBytes;
Cipher cipher;
cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
encryptedBytes = cipher.doFinal(plain.getBytes());
return Base64.encodeToString(encryptedBytes, Base64.DEFAULT);
}
//I call these functions in this manner.
private final String pubKeyString =
//"-----BEGIN PUBLIC KEY-----" +
"MIG..." +
"...";
//"-----END PUBLIC KEY-----"
PublicKey pubKey = RSAFunctions.getPublicKeyFromString(pubKeyString);
String encData = RSAFunctions.RSAEncrypt("prova", pubKey);
The publickey.php and privatekey.php file are generated in php with this code:
<?php
include('./Crypt/RSA.php');
$rsa = new Crypt_RSA();
extract($rsa->createKey()); // == $rsa->createKey(1024) where 1024 is the key size
$File1 = "./privatekey.php";
$Handle = fopen($File1, 'w');
fwrite($Handle, "<?php \$privatekey=\"" . $privatekey . "\"?>");
fclose($Handle);
$File2 = "./publickey.php";
$Handle = fopen($File2, 'w');
fwrite($Handle, "<?php \$publickey=\"" . $publickey . "\"?>");
fclose($Handle);
?>
In php I use this code for decrypt data:
<?php
include('Crypt/RSA.php');
require('privatekey.php');
$rsa = new Crypt_RSA();
$rsa->loadKey($privatekey); // private key
$base64_string = $_GET["data"];
$base64_string = str_replace(' ', '+', $base64_string);
$ciphertext = base64_decode( $base64_string );
//$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_OAEP);
$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_PKCS1);
$plaintext = $rsa->decrypt($ciphertext);
echo $plaintext;
?>
I've also made a php crypt script for testing my decrypt php function. This is the code of my encrypt.php:
<?php
include('Crypt/RSA.php');
require('publickey.php');
$rsa = new Crypt_RSA();
$rsa->loadKey($publickey); // public key
$plaintext = $_GET["data"];
//$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_OAEP);
$ciphertext = $rsa->encrypt($plaintext);
echo base64_encode( $ciphertext );
?>
I've no problem when encrypt and decrypt text using only php, but if I use the encrypted data made with android app, php give me an error in decrypting.
Thanks for the attention.
In your php there is :
CRYPT_RSA_ENCRYPTION_PKCS1
but when you create your Cipher object on Android you omit the mode and padding
cipher = Cipher.getInstance("RSA");
you should try something like
Cipher c = Cipher.getInstance("AES/CBC/PKCS1Padding");
ref :
http://developer.android.com/reference/javax/crypto/Cipher.html

php encrypt and decrypt

can anyone tell me how to encrypt and decrypt a URL string ?
I want to encrypt a hyperlink ...
If you can use database,you could create a table to map a file to an id.
Create a 'mapping_table'
id - integer
file_location - string
Your URL would look something like localhost/waterwell/e_book.php?id=12 .
make links that return to your server with querystring GET params identifying the file. the server can then do echo file_get_contents() after you figure out which file from the inputs
In your example it's trivial. simply omit the portion of the url you don't want shown and fill it back in on the server.
$confirmpassword = $_POST['confirmpassword'];
$value_check = true;
$ciphering = "AES-128-CTR";
$options = 0;
$encryption_iv = '1234567891011121';
$encryption_key = "GeeksforGeeks";
$confirmpasswordencryption = openssl_encrypt($confirmpassword, $ciphering,$encryption_key, $options, $encryption_iv);
$encryption = "pABqPJhobIMHzqai"
$ciphering = "AES-128-CTR";
$options = 0;
$decryption_iv = '1234567891011121';
// Store the decryption key
$decryption_key = "GeeksforGeeks";
// Use openssl_decrypt() function to decrypt the data
$decryption=openssl_decrypt ($encryption, $ciphering,
$decryption_key, $options, $decryption_iv);
// Display the decrypted string
echo "Decrypted String: " . $decryption;

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