Encrypt decrypt issue with new php version - php

I have a encrypt function on one of my website which is running on PHP 5.3.29
The function works proper on this version of PHP. The function is:
function encrypt($text) {
return trim(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, SALT, $text, MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND))));
}
I have another website which is running on PHP 5.6.29. The same function does not return anything on this version. It returns blank.
Similarly I have decrypt function which is also not working on PHP 5.6.29
function decrypt($text) {
return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, SALT, base64_decode($text), MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND)));
}
I need to make this function to work on PHP 5.6.29 as my websites are connected via API. I have no idea how I can make this to work. Any help please?

You're probably passing an incorrect value for SALT. From the manual:
Invalid key and iv sizes are no longer accepted. mcrypt_encrypt() will now throw a warning and return FALSE if the inputs are invalid. Previously keys and IVs were padded with '\0' bytes to the next valid size.
This was a change made to PHP 5.6, which lines up with what you're seeing.
Note that an encryption key is not the same as a hashing salt, which can generally be of any length.

I think you have problem with SALT. If you will give 32 character SALT then these functions will give output in PHP 5.6.29 as well.

Related

PHP simple string encryption and decryption

Is there a simple function in PHP other than mcrypt() that can encrypt and decrypt a string.
I was trying out the code below, but that's too much for what I'm trying to do.
I'm trying to encrypt page numbers that are sent with a URL, so users will not be able to access a page simply by making changes to the page number in the browsers location bar. My page number has some other data too, that I do not want visible to users.
Example:
http://www.example.com/p10:05 to http://www.example.com/895f852d22d558esc23
I don't need such high level encryption and decryption like in the code below. Just something that can do like in my example is sufficient.
Another reason I do not like using mcrypt, is because of the 2 == it adds to the end of a string.
$salt ='iodine';
function simple_encrypt($text)
{
global $salt;
return trim(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $salt, $text, MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND))));
}
function simple_decrypt($text)
{
global $salt;
return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $salt, base64_decode($text), MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND)));
}
echo simple_encrypt('Hello')
MCrypt does not add those == characters to the string, the base 64 encoding does. It is possible to simply remove them. Just make sure that the base64 string is a multiple of 4 characters by adding them back again when the string is received.
Base 64 can contain the '/' and '+' characters by default (depending on the input). Replace them with URL safe - and _ characters.
The code shows MCRYPT_RIJNDAEL_256 which is not AES; it is Rijndael with a 256 bit block size. Using MCRYPT_RIJNDAEL_128 - which is AES - would be better. This still allows the code to encrypt up to 16 character number values and it will decrease the output size.
There is no need to generate an IV if ECB mode is used, so remove that part of the method. There is no need to add unnecessary work for the system random number generator.
The $salt value is actually the key value, better name it as such to avoid confusion.

Exactly how do I use blowfish in PHP? [duplicate]

This question already has answers here:
Two-way encryption: I need to store passwords that can be retrieved
(8 answers)
Closed 9 years ago.
Possible Duplicate:
Best way to use PHP to encrypt and decrypt passwords?
I've been doing a lot with PHP recently and want to make my first login/registration system. As such I've been doing a lot of reading online to figure out the best method(s) for doing this. I've come across a couple of guides and I'm confused on a few instances and I'd like to be sure before I start down this road.
My question is how exactly do I use blowfish? I've read that crypt() will auto select blowfish if an appropriate salt is provided. If that is the case, What makes a salt blowfish appropriate?
Right now, I have a script that makes a salt out of the date and time, a random number, then hash that for the salt. Is that something I can use with blowfish or not?
In short: don't build it yourself. Use a library.
In PHP 5.5, there will be a new API available to make this process easier on you. Here's the RFC for it.
I've also created a backwards-compatibility library for it here: password-compat:
$hash = password_hash($password, PASSWORD_BCRYPT);
And then to verify:
if (password_verify($password, $hash)) {
/* Valid */
} else {
/* Invalid */
}
And if you want another library, check out phpass
In short, don't do it yourself. There's no need. Just import the library and be done with it...
Take a look at http://php.net/manual/en/function.crypt.php
If you scroll down about 1/3, you should see the heading: Example #3 Using crypt() with different hash types. Hopefully this will help! and your salt should be fine!
Try this - its untested, I just whipped it up to show how to use the BLOWFISH algo with PHP
<?php
class cipher {
private static $mode = 'MCRYPT_BLOWFISH';
private static $key = 'q!2wsd#45^532dfgTgf56njUhfrthu&^&ygsrwsRRsf';
public static function encrypt($buffer){
$iv = mcrypt_create_iv(mcrypt_get_iv_size(constant(self::$mode), MCRYPT_MODE_ECB), MCRYPT_RAND);
$passcrypt = mcrypt_encrypt(constant(self::$mode), self::$key, $buffer, MCRYPT_MODE_ECB, $iv);
$encode = base64_encode($passcrypt);
return $encode;
}
public static function decrypt($buffer){
$decoded = base64_decode($buffer);
$iv = mcrypt_create_iv(mcrypt_get_iv_size(constant(self::$mode), MCRYPT_MODE_ECB), MCRYPT_RAND);
$decrypted = mcrypt_decrypt(constant(self::$mode), self::$key, $decoded, MCRYPT_MODE_ECB, $iv);
return $decrypted;
}
}
?>
IMPORTANT!! CHANGE THE $key VALUE TO ANOTHER RANDOM STRING!
Usage:
To Encrypt:
$mystring = 'a quick brown fox jumped over the lazy llama';
$mystring = cipher::encrypt($mystring);
To Decrypt:
$mystring = cipher::decrypt($myencryptedstring);

Rijndael PHP encode FLASH decode

I am trying to pass some encrypted data to a flash , but I got stuck somewhere in the middle.
Im using RIJNDAEL algorithm to encode the data in PHP :
function encrypt($text){
$key = "53cded30ff7ba54d65b939fd594e3d63";
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CBC); //get vector size on CBC mode
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND); //Creating the vector
$cryptedtext = mcrypt_encrypt (MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_CBC, $iv); //Encrypting using MCRYPT_RIJNDAEL_256 algorithm
return $cryptedtext;
}
And im using the AS3CRYPT library to decrypt the value in flash.
The problem is that if I try to decode the value in flash or even in the demo of AS3CRYPT, it doesnt work.
I also tried to return the data from PHP encoded with base64_encode but still not working.
The output from PHP is something like : flashvar=Á žJcV—µg)7¾1´‘5{Ò<¶Ù$þS„§”
Probably I did something wrong in the PHP ...
PHP doesn't add any padding, which is likely needed.
You'll have to pad it manually, take a look at this post on PHP.net which explains one method of achieving PKCS7 padding compatibility.
Beyond that, make sure you're setting the matching confidentiality mode (CBC) and cipher within "AS3CRYPTO".

Cryptography libraries conflict (MCrypt, libgcrypt)

I'm trying to perform encryption and decryption (Rijndael 256, ecb mode) in two different components:
1. PHP - Server Side (using mcrypt)
2. C + + - Client Side (using gcrypt)
I ran into a problem when the client side could not decrypt correctly the encrypted data (made by the server side)
so... i checked the:
1. initial vector - same same (32 length)
2. the key - again the same key on both sides..
so i wrote some code in C++ that will encrypt the data (with the same parameters like in the php)
and i found out that the encrypted data contains different bytes (maybe encoding issue??)
I'll be more than glad to get some help
PHP - MCrypt
// Encrypt Function
function mc_encrypt($encrypt, $mc_key) {
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
$iv = "static_init_vector_static_init_v";
echo "IV-Size: " . $iv_size . "\n";
echo "IV: " . $iv . "\n";
$passcrypt = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $mc_key, $encrypt, MCRYPT_MODE_ECB, $iv);
print_hex($passcrypt);
return $encode;
}
mc_encrypt("Some text which should be encrypted...","keykeykeykeykeykeykeykeykeykeyke");
I'll post the C++ code in a comment
Thanks,
Johnny Depp
OK. I'll make my comment an answer:
An Initialization Vector (IV) isn't used in ECB mode. If it is provided different implementations might work differently.
If you want to be sure the implementations will work correctly then use an IV of 0 (zero). Even though you provide the IV, both implementations SHOULD ignore it but one can never be sure about that. Not providing an IV in ECB mode should work aswell but again, it all depends on the implementations.
According to the PHP documentation MCrypt will ignore it. GCrypt I'm not sure about.
mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB) should actually return 0 since you specify ECB mode.
Edit:
Do not call mcrypt_get_iv_size or mcrypt_create_iv.
Instead call mcrypt_encrypt without an IV. According to the PHP documentation all bytes in the IV will be set to '\0'.
Same goes for the C++ code. No need to set any IV at all. The libgcrypt code is complex but from glancing at the source of version 1.4.5 then in ECB mode it seems the IV isn't used at all.
If the resulting ciphertext still differs then the problem is something else.
A couple of possibilities comes to mind:
Encoding - Is the same encoding used in both the server and the client?
Endianness - What type of systems are the server and the client? Big- vs Little-endian?

PHP: mcrypt mangles beginning of string to garbage

I need medium to strong encryption on serverside, so I thought I would use mcrypt with PHP. If I use the functions below the beginning of my original string turns into binary garbage after decryption. (This is not the usual problem of getting appended additional garbage, instead my string is altered.) According to the documentation, mcrypt_encrypt() should have padded enough characters to match the block size of the selected algorithm but I suspect it does not work.
However, if I pad it manually to the block size of 128 bit (16 bytes) of Rijndael, it doesn't work either. The only way I can get this to work is by prepending some string long enough to (likely) cover the garbaged block and add a known prefix like "DATA#" between that string and my data. After decryption that block has been partially mangled but my prefix and all data after that has been correctly decrypted.
$GLOBALS['encryptionmarker'] = 'DATA#';
function encrypt($plain, $key) {
/*
// workaround because beginning of decrypted string is being mangled
// so we simply prefix with some text plus marker
$prefix = str_pad('', 128, '#', STR_PAD_RIGHT).$GLOBALS['encryptionmarker'];
$plain = $prefix.$plain;
*/
$encrypted = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $plain, MCRYPT_MODE_CFB,
mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CFB),
MCRYPT_DEV_URANDOM));
return $encrypted;
}
function decrypt($encrypted, $key) {
$decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key, $encrypted, MCRYPT_MODE_CFB,
mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CFB),
MCRYPT_DEV_URANDOM));
/*
// workaround: remove garbage
$pos = strpos($decrypted, $GLOBALS['encryptionmarker']);
$decrypted = trim(substr($decrypted, $pos + strlen($GLOBALS['encryptionmarker'])));
*/
return $decrypted;
}
What's wrong with my functions? Why do I have to prefix my data like that (I consider it a dirty workaround, so I would like to fix it)?
Storing the encrypted data is not the problem; decrypting it immediately after encryption without storing it to a database results in the same errors.
Your problem is that you are generating a new, different, random IV on the receiving side. This doesn't work, as you've seen.
The receiver needs to know the IV that the sender used; so you have to send it along with the encrypted data and pass it to mcrypt_decrypt().
Note that you must also use mhash() with a key (a different key to the encryption key) to generate an HMAC over the message, and check it on the receiving side. If you do not, a man-in-the-middle can trivially modify parts of your message without you detecting it.
Use the same IV in en- and decryption. The IV is not a shared secret, but has to be shared. You may consult Wikipedia: IV
$IV = mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CFB),
MCRYPT_DEV_URANDOM));
The IV must be transferred ONCE. You may want to increment the value of IV for each packet. But this can be done on both sides independently.

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