need help to convert the following function in php. Can any one help me please ?
OpenEdge Progress 4 GL
DEFINE VARIABLE cClearText AS CHARACTER NO-UNDO.
DEFINE VARIABLE rBinaryKey AS RAW NO-UNDO.
DEFINE VARIABLE rEncryptedValue AS RAW NO-UNDO.
DEFINE VARIABLE cEncryptedText AS CHARACTER NO-UNDO.
ASSIGN
cClearText = "This is the clear text string to be encrypted."
rBinaryKey = GENERATE-PBE-KEY("password")
SECURITY-POLICY:SYMMETRIC-ENCRYPTION-ALGORITHM = "AES_OFB_128"
SECURITY-POLICY:SYMMETRIC-ENCRYPTION-KEY = rBinaryKey
SECURITY-POLICY:SYMMETRIC-ENCRYPTION-IV = ?
rEncryptedValue = Encrypt (cClearText)
cEncryptedText = BASE64-ENCODE(rEncryptedValue)
.
MESSAGE "Encrypted Message:" cEncryptedText
VIEW-AS ALERT-BOX INFO BUTTONS OK.
in php
$key = "password";
$text = "This is the clear text string to be encrypted.";
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
/*$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND); */
$crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_ECB, $iv);
echo $crypttext;
but not the same result???
Is it just my imagination or are you using AES_OFB_128 as the algorithm with the OpenEdge code and RIJNDAEL_256 for the PHP code?
It seems to me that you should get a different result.
Shouldn't you have the same mode and key size? (IOW AES_ECB_256 instead of AES_OFB_128 in the OpenEdge code.)
changed to SECURITY-POLICY:SYMMETRIC-ENCRYPTION-ALGORITHM = "AES_CBC_128".
In php:
$crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key, $text, MCRYPT_MODE_CBC);
The problem is that Converting the passphrase into a password based encryption key (PBE-KEY)
through Progress is not returning the same values as in php.
4gl:
rawBinaryKey = GENERATE-PBE-KEY("pw").
Not returning the same on php:
$key = "pw";
I need to know how to execute through php a function returning the same value as "GENERATE-PBE-KEY("pw")"
is returning on Progress 4GL.
Kind regards
Related
I'm using the openssl_encrypt / decrypt method in my website but i'm having some troubles with the $tag option
openssl_encrypt ( $data, $method, $key, $options, $iv, $tag )
openssl_decrypt ( $data, $method, $key, $options, $iv, $tag )
from http://php.net/manual/en/function.openssl-encrypt.php, the definition of tag is: The authentication tag passed by reference when using AEAD cipher mode (GCM or CCM). But i didn't understand it.
I tried it in my codes
$data = "text to be encrypted";
$cipher = "aes-128-gcm";
$key = "0123456789abcdefghijklmnob123456";
$option = 0;
$ivlen = openssl_cipher_iv_length($cipher);
$iv = openssl_random_pseudo_bytes($ivlen);
if (in_array($cipher, openssl_get_cipher_methods())){
$encryptedData = openssl_encrypt($data,$cipher,$key,$option,$iv,$tag);
echo $encryptedData;
$decryptedData = openssl_decrypt($encryptedData,$cipher,$key,$option,$iv,$tag);
echo $decryptedData;
}
i got this result:
encrypted text: Vlx/yKkPhg0DpD0YKvnFKRiCh/I=
decrypted text: text to be encrypted
which is correct. but if i directly decrypt the encrypted text this way:
$data = "text to be encrypted";
$cipher = "aes-128-gcm";
$key = "0123456789abcdefghijklmnob123456";
$option = 0;
$ivlen = openssl_cipher_iv_length($cipher);
$iv = openssl_random_pseudo_bytes($ivlen);
if (in_array($cipher, openssl_get_cipher_methods())){
$encryptedData = "Vlx/yKkPhg0DpD0YKvnFKRiCh/I=";
$decryptedData = openssl_decrypt($encryptedData,$cipher,$key,$option,$iv,$tag);
echo $decryptedData;
}
i'm getting:
Notice: Undefined variable: tag
if someone could explain to me why this is happening and what should be the value of $tags. thanks
The tag that PHP is complaining about is an essential aspect of AES when using GCM mode of operation. In this mode, not only does the AES block cipher get applied, but an authentication tag gets calculated as well. It is an array of bytes that represents a MAC (Message Authentication Code) that can be used to verify the integrity of the data and wen decrypting. That same tag needs to be provided to do that verification. See the Wikipedia page about Galois/Counter Mode for more details.
So in order to successfully decrypt that ciphertext, you need to capture the $tag variable resulting from the openssl_encrypt() invocation and feed it into the openssl_decrypt() invocation. You did not do that, hence the complaint about the missing tag. Note that the tag (typically) contains non-readable characters so it is more convenient to store it in a base64 encoded format.
In addition to the $tag variable, you should also provide the same value for the $iv variable to the openssl_decrypt() method as you used in the openssl_encrypt() invocation. Again, base64 encoding makes that easier.
A quick test below demonstrates all this, where I first modified your script to print more stuff and then used the provided script to decrypt:
$ php test1.php
iv base64-ed: vBKbi8c6vCyvWonV
plaintext: text to be encrypted
ciphertext base64-ed: z28spOd3UEDmj+3a8n/WK11ls7w=
GCM tag base64-ed: OIAggQCGUbPgmPN6lFjQ8g==
$ php test2.php
decrypted ciphertext: text to be encrypted
where the code for test2.php is the following:
$cipher = "aes-128-gcm";
$key = "0123456789abcdefghijklmnob123456";
$option = 0;
$iv = base64_decode("vBKbi8c6vCyvWonV");
if (in_array($cipher, openssl_get_cipher_methods())){
$encryptedData = "z28spOd3UEDmj+3a8n/WK11ls7w=";
$tag = base64_decode("OIAggQCGUbPgmPN6lFjQ8g==");
$decryptedData = openssl_decrypt($encryptedData,$cipher,$key,$option,$iv,$tag);
echo("decrypted ciphertext: ".$decryptedData."\n");
}
I have the following encrypt code:
function encryptData($value){
$key = "7685647tfyr65413285746352413sgfh";
$text = $value;
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
$crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_ECB, $iv);
return $crypttext;
}
echo 'Encrpt: ' . encryptData('This is just a test');
The output is: Encrpt: yUB�F3�*ľ�G-�ۅd�8�f�_�X/O
I'm going to place this into a mySQL database but was unsure if it would accept those types of weird characters?
Am i doing this correctly?
Yes, you are doing it correctly, however the output is a binary value. To be save, it's good practice to encode it to a 'regular' string via
$encrypted_base64 = base64_encode($crypttext);
Just remember to do the opposite before decoding;
$crypttext = base64_decode($encrypted_base64);
First, excuse the question, it might be a simple problem, but I have troubles understanding the encryption methods..
I'm using the following functions to encrypt / decrypt:
private function encodemc($value,$skey){
if(!$value){return false;}
$skey = substr($skey, 2, 4);
$text = $value;
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
$crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $skey, $text, MCRYPT_MODE_ECB, $iv);
return trim($this->safe_encode($crypttext)); // safe_encode adds another encoding using `base64_encode`
}
private function decodemc($value,$skey){
if(!$value){return false;}
$skey = substr($skey, 2, 4);
$crypttext = $this->safe_decode($value);
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
$decrypttext = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $skey, $crypttext, MCRYPT_MODE_ECB, $iv);
return trim($decrypttext);
}
The $key looks like this: 570c45546dwq45gjk191.
I pass the value to be encrypted to the first function, then I save it to the db, and then I retrieve it from the db, I decrypt it and show it as html text.
The problem is that some text does not get decrypted/encrypted right, and it displays in the html page as if it was in the wrong text encoding.
The weird part is that out of 10 items, only 2 or 3 are garbled, depending on the key.
In addition, sometimes only a portion of the string is garbled.
I've found out that what causes the garbling are some random letters. For instance, when using the above key the letter S breaks the code and the text gets garbled.
So then I've applied substr($skey, 2, 4); to the key to see if anything changed. Turns out that if I change the key the characters that break the code are different.
But even with a key of lenght == 1 the problem persists.
Any idea on what's the problem?
EDIT:
Here the rest of the code.
private function safe_encode($string) {
$data = base64_encode($string);
$data = str_replace(array('+','/','='),array('-','_',''),$data);
return $data;
}
private function safe_decode($string) {
$data = str_replace(array('-','_'),array('+','/'),$string);
$mod4 = strlen($data) % 4;
if ($mod4) {
$data .= substr('====', $mod4);
}
return stripslashes(base64_decode($data));
}
That seems like a very weird issue.
I do not have a definite answer for you, but here are a couple of things you can try.
Encrypt/Decrypt without going to the database. If the issues goes away, then there is a problem with the database handling the characters output though the encryption function.
Trim the value before you encrypt it. If the issues goes away, then the trim after encryption is wrong.
Remove the safe_encode and safe_decode code. If the issue goes away, then these functions are adding/removing important things.
It is important that you do all the above in one go, as there might be multiple issues. If the above steps remove the issues, then reintroduce them one at a time to identify which is causing the problem.
I'm in the need of decrypting with PHP (or Javascript) some service calls. I've spent all the day trying to accomplish, this, but I've been unable to decrypt it properly.
As a reference, the service provider sent me the following decryption sample code in Java:
DESKeySpec dks = new DESKeySpec("keyword".getBytes());
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
SecretKey key = keyFactory.generateSecret(dks);
Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
SecureRandom sr = new SecureRandom();
cipher.init( Cipher.DECRYPT_MODE, key ,sr);
byte b[] = response.toByteArray();
byte decryptedData[] = cipher.doFinal( b );
I think I'm in the correct path by using:
$td = mcrypt_module_open(MCRYPT_DES, '', 'ecb', '');
$iv_size = mcrypt_enc_get_iv_size($td);
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
$key = substr($keyword, 0, mcrypt_enc_get_key_size($td));
mcrypt_generic_init($td, $key, $iv);
$decrypted = mdecrypt_generic($td, $data);
$decrypted = pkcs5_unpad($decrypted);
But, frankly, I'm sure I'm messing everything with the $iv creationg and $keyword setup (or maybe with $data or $decrypted types?). The pkcs5_unpad function is as follows:
function pkcs5_unpad($text)
{
$pad = ord($text{strlen($text)-1});
if ($pad > strlen($text)) return false;
return substr($text, 0, -1 * $pad);
}
I'm not only a noob on php, but also on cryptography techniques... could you please help me to solve this issue?
Make sure your key consists of the same bytes (strings may be encoded differently) and feed it a IV filled with zero's. ECB mode does not use an IV (and the PHP manual specifies as much), but if you do give it one default it to all zero's - the IV will be XOR'ed with the first plain text block, so setting it to all zero's will cancel out that operation. Also, make sure that the input cipher data is the same. Ignore the padding in the first instance, you should be able to check if the result is correct before unpadding.
I have a class that takes a string in this format:
000067000000000012620060324b38e2cab3353
, encrypts the string then appends it as a get variable in a URL.
The class that does the encryption has a function that looks like this:
private function _code_encryption($enc_type,$a_string){
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CBC);
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
if($enc_type == self::ENCRYPT_STRING){
//encrypt then return base64 encoded
$encrypted = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, self::AUTH_ENCRYPTION_KEY, $a_string, MCRYPT_MODE_CBC, $iv);
return base64_encode($encrypted);
}elseif($enc_type == self::DECRYPT_STRING){
$decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, self::AUTH_ENCRYPTION_KEY, base64_decode($a_string), MCRYPT_MODE_CBC, $iv);
return trim($decrypted);
}
}
When the string is encrypted I urlencode the value and add it to the url like the url looks like "https://secure.mysite.com/index.php?action=someaction&transfer_code=XXXXX where XXXX is the urlencoded encrypted string.
Now, when the url is parsed and processed the value of $_GET['transfer_code'] is getting passed into the above _code_encryption function but is not returning the correctly decrypted value and instead returns garbled characters my browser doesn't render. Is there a requirement for the length of the key I use for encryption/decryption? I tried something like
$key = hash('sha256',self::AUTH_ENCRYPTION_KEY,true);
but that didn't work either...
Also, I am not urldecoding the $_GET['transfer_code'] variable because the php man pages state that get vars are already urlencoded...
Should I be UTF-8 encoding the alphanumeric string BEFORE encryption/base64_encoding, or will that even make any difference?
You use a random IV to encrypt, and the a different random IV to decrypt. The decrypted string will never ever match the original. To properly decrypt the original string you must use the same IV that was used during encryption. Usually this is achieved by prepending the IV used to the encrypted string. At decryption time you must first extract the IV from the value, initialize the key with this value, then decrypt the rest usign the properly initialized key.
I don't have a parser to validate this but it should be something like:
private function _code_encryption($enc_type,$a_string){
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CBC);
if($enc_type == self::ENCRYPT_STRING){
//encrypt then return base64 encoded
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
$encrypted = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, self::AUTH_ENCRYPTION_KEY, $a_string, MCRYPT_MODE_CBC, $iv);
return base64_encode($iv.$encrypted);
} elseif ($enc_type == self::DECRYPT_STRING){
$decoded = base64_decode($a_string);
$iv = substr($decoded,0,$iv_size);
$cipher = substr($decoded,$iv_size);
$decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, self::AUTH_ENCRYPTION_KEY, $cipher, MCRYPT_MODE_CBC, $iv);
return trim($decrypted);
}
}