PHP: Mcrypt
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2
Anonymous
1 year ago
These are two simple functions I built for 256-bit encryption/decryption with mcrypt. I've decided to use MCRYPT_RIJNDAEL_128 because it's AES-compliant, and MCRYPT_MODE_CBC. (ECB mode is inadequate for many purposes because it does not use an IV.)
This function stores a hash of the data to verify that the data was decrypted successfully, but this could be easily removed if necessary.
<?php
) {
// Build a 256-bit $key which is a SHA256 hash of $salt and $password.
);
// Build $iv and $iv_base64. We use a block size of 128 bits (AES compliant) and CBC mode. (Note: ECB mode is inadequate as IV is not used.)
);
if (;
// Encrypt $decrypted and an MD5 of $decrypted using $key. MD5 is fine to use here because it's just to verify successful decryption.
));
// We're done!
;
}
function ) {
// Build a 256-bit $key which is a SHA256 hash of $salt and $password.
);
// Retrieve $iv which is the first 22 characters plus ==, base64_decoded.
);
// Remove $iv from $encrypted.
);
// Decrypt the data. rtrim won't corrupt the data because the last 32 characters are the md5 hash; thus any \0 character has to be padding.
);
// Retrieve $hash which is the last 32 characters of $decrypted.
);
// Remove the last 32 characters from $decrypted.
);
// Integrity check. If this fails, either the data is corrupted, or the password/salt was incorrect.
;
// Yay!
return $decrypted;
}
?>
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ysfbauchi at yahoo dot com
1 year ago
//This is a des, 3des, aes and gost encryption program i wrote using php for my assignment
<?php
])) {
];
];
];
} else {
die("algorithm not selected");
}
if (){
die("Please enter a text to encrypt! ");
}
if (){
die("Please enter a key! ");
}
function )
{
);
);
);
echo ;
echo ;
echo "<p><b>Key size :</b> ";
foreach ()
{
echo ;
}unset($value);
}
function )
{
);
);
);
echo "<html><hr size='2' ></html>";
echo "<P><P><b>Plain Text : </b>";
echo($themsg);
echo "<p><b>Cipher Text : </b> ";
echo ;
);
);
die();
}
if (){
);
);
);
}elseif (){
);
);
);
}elseif (){
);
);
);
}elseif (){
);
);
);
}else {
die("Please choose an algorithm!");
}
?>
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ghoffman at salientdigital dot com
2 years ago
If you want a quick way to see what ciphers, modes, key, block and iv sizes are supported on your server, try something like the following.
Note: I used this simple bash: `locate libmcrypt` from terminal on Mac OS X to determine the install paths to the algorithms and modes directories. Lots of function calls generate warnings for certain ciphers, hence the use of error suppression.
<?php
$modes = mcrypt_list_modes();
();
foreach()
{
echo ;
foreach()
{
echo ;
@(
$cipher,
'/usr/local/libmcrypt-2.5.8/modules/algorithms/',
$mode,
'/usr/local/libmcrypt-2.5.8/modules/modes/');
@);
@);
@);
@);
echo "
<pre>
key_size: ")
.)
.)
." </pre>\n";
;
;
;
;
}
}
?>
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Maarten Malaise
2 years ago
people using phpmyadmin are redirected to this manual if they don't have mcrypt installed. If you want to install mcrypt on debian, first check your php version:
yourserver# php --version
Then install the appropriate version of mcrypt (php5-mcrypt if your php version is 5.x)
yourserver# apt-get install php4-mcrypt
...or...
yourserver# apt-get install php5-mcrypt
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-1
Anonymous
3 years ago
When using 3DES between PHP and C#, it is to be noted that there are subtle differences that if not strictly observed, will result in annoying problem encrypt/decrypt data.
1), When using a 16 bytes key, php and c# generates total different outcome string. it seems that a 24 bytes key is required for php and c# to work alike.
2), php doesnt have a "padding" option, while c# has 3 (?). My work around is to add nulls i.e. chr(0) to the end of the source string to make its size times of 8, while in c#, PaddingMode.Zeros is required.
3) the key size has to be times of 8, in php, to make it work for c#.
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rainbowarrior
2 years ago
for Suse Linux Enterprise 11 I had used this to resolve the issue (as root)
# yast -i php5-mcrypt
# rcapache2 restart
hope this helps
