使用PHP使用GPG加密

Question

I need help encrypting files in PHP using GPG. I have done some research but I can't find a solution yet.

Using GPG in command line works perfectly but when I try from PHP I get a return value 2. I have also tried passing '--yes --always-trust' as extra switches to command as suggested in one of the answers on SO but no joy.

I have tried using the gnupg function built into PHP - all the examples I've found show how to encrypt strings and not files. reading the file as a string will not work for me because I'm working on large files as big as 15MB.

I need help!

Environment Details

OS: Windows 7
PHP installation: WAMP Server 2.1

Code

$path = "c:\wamp\www";
$recipient = "Test user";
$encrypted_file = "c:\wamp\www\test.txt.gpg";
$decrypted_file = "c:\wamp\www\decrypted_test.txt";
$plain_file = "c:\wamp\www\test.txt";

exec('gpg --homedir $path --recipient $recipient --output $encrypted_file --encrypt $plain_file --yes --always-trust', $answer, $rtn);

var_dump($answer);
var_dump($rtn);
echo "<br />ANSWER: ".$answer;
echo "<br />RTN: ".$rtn;

Output

array(0) { } int(2) 
ANSWER: Array
RTN: 2
PHP User: nt authority\system

Answer 1

Try changing

exec('gpg --homedir $path --recipient $recipient --output $encrypted_file --encrypt                     $plain_file --yes --always-trust', $answer, $rtn);

To

exec("gpg --homedir $path --recipient $recipient --output $encrypted_file --encrypt                     $plain_file --yes --always-trust", $answer, $rtn);

Notice I changed single quotes to double

http://php.net/manual/en/language.types.string.php

Answer 2

You mix up the use of single quote & double quote.

$path = 'c:\wamp\www';
$recipient = 'Test user';
$encrypted_file = 'c:\wamp\www\test.txt.gpg';
$decrypted_file = 'c:\wamp\www\decrypted_test.txt';
$plain_file = 'c:\wamp\www\test.txt';

And in this line:

exec("C:\\Wamp\\WWW\\gpg --homedir $path --recipient $recipient --output $encrypted_file --encrypt                     $plain_file --yes --always-trust", $answer, $rtn);

Use double quote when the string is needed to be parsed by PHP (take a note of Escape characters); use single quote when the string does not need to be parsed.