Thread: pgcrypto & php

Hello,


I am storing certain data encrypted by pgcrypto in my database.

Here are the commands I use to test the functionality:

CREATE TABLE crypto (
id              SERIAL PRIMARY KEY,
title           VARCHAR(50),
crypted_content BYTEA
);


INSERT INTO  crypto VALUES (1,'test1',encrypt('daniel', 'fooz', 'aes'));
INSERT INTO  crypto VALUES (2,'test2',encrypt('struck', 'fooz', 'aes'));
INSERT INTO  crypto VALUES (3,'test3',encrypt('konz', 'fooz', 'aes'));

SELECT * FROM crypto;

SELECT *,decrypt(crypted_content, 'fooz', 'aes') FROM crypto;

SELECT *,decrypt(crypted_content, 'fooz', 'aes') FROM crypto WHERE decrypt(crypted_content, 'fooz', 'aes')='struck';


There are certain occasions where I would like to be able to decrypt/ encrypt the data in PHP itself. Is this possible
withthe "Mcrypt Encryption Functions" of PHP? 

I have already tried it, by as I am no expert in cryptography, I have difficulties finding the right syntax.
This is the code I used to try it out:

$test=new db_sql_user;
$test->query("select crypted_content from crypto WHERE id=1;");
$crypt=$test->result();

echo "<br />";
echo "crypted content from postgresql: " .$crypt;
$array = unpack("c2chars/nint", $crypt);
echo $array;
echo "<br />";
echo mcrypt_decrypt ( MCRYPT_RIJNDAEL_128 , "fooz", $crypt, cbc);
echo "<br />";
echo  mcrypt_cbc (MCRYPT_RIJNDAEL_128, "fooz", $crypt , MCRYPT_DECRYPT);


This is the output:

crypted content from postgresql: g°ñ\220399ùû¹qyg®Û~Array
5*X]Nl\x{2022}u
5*X]Nl\x{2022}u


Best regards,
Daniel Struck


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Finally, it works :-)

$crypt=$test->result();
echo "<br />";
echo "crypted content from postgresql: " .$crypt;
echo "<br />";
$crypt=pg_unescape_bytea($crypt);
echo $crypt;
echo "<br />";
echo mcrypt_decrypt ( MCRYPT_RIJNDAEL_128 , "fooz", $crypt, cbc);
echo "<br />";
echo  mcrypt_cbc (MCRYPT_RIJNDAEL_128, "fooz", $crypt , MCRYPT_DECRYPT);

OUTPUT:

crypted content from postgresql: g°ñ\220399ùû¹qyg®Û~
g°ñ399ùû¹qyg®Û~
daniel
daniel


You have to use the function "pg_unescape_bytea();" from PHP when you extract bytea data from postgresql. How stupid of
me,should have known that the bytea data would be escaped ;-) 

Daniel