Create SSH form for PHP keys

Question

I want to generate ssh keypair from php. Can anyone advise me how to do this? I tried shell_exec, but the shell asks questions, so the command does not work. I would like to indicate the file name and the path where the keys should be placed after generation.

Answer 1

This is based on Converting the RSA public key public key to OpenSSH (PHP) format . Thanks shevron .

<?php
$rsaKey = openssl_pkey_new(array( 
              'private_key_bits' => 1024, 
              'private_key_type' => OPENSSL_KEYTYPE_RSA));

$privKey = openssl_pkey_get_private($rsaKey); 
openssl_pkey_export($privKey, $pem); //Private Key
$pubKey = sshEncodePublicKey($rsaKey); //Public Key

$umask = umask(0066); 
file_put_contents('/tmp/test.rsa', $pem); //save private key into file
file_put_contents('/tmp/test.rsa.pub', $pubKey); //save public key into file

print "Private Key:\n $pem \n\n";
echo "Public key:\n$pubKey\n\n";

function sshEncodePublicKey($privKey) {
    $keyInfo = openssl_pkey_get_details($privKey);
    $buffer  = pack("N", 7) . "ssh-rsa" .
    sshEncodeBuffer($keyInfo['rsa']['e']) . 
    sshEncodeBuffer($keyInfo['rsa']['n']);
    return "ssh-rsa " . base64_encode($buffer);
}

function sshEncodeBuffer($buffer) {
    $len = strlen($buffer);
    if (ord($buffer[0]) & 0x80) {
        $len++;
        $buffer = "\x00" . $buffer;
    }
    return pack("Na*", $len, $buffer);
}
?>

Answer 2

I would use phpseclib, a pure PHP RSA implementation :

<?php
include('Crypt/RSA.php');

$rsa = new Crypt_RSA();

$rsa->setPublicKeyFormat(CRYPT_RSA_PUBLIC_FORMAT_OPENSSH);

extract($rsa->createKey());
echo "$publickey\r\n\r\n$privatekey";
?>

Output Example:

ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAAgQCqGKukO1De7zhZj6+H0qtjTkVxwTCpvKe4eCZ0FPqri0cb2JZfXJ/DgYSF6vUpwmJG8wVQZKjeGcjDOL5UlsuusFncCzWBQ7RKNUSesmQRMSGkVb1/3j+skZ6UtW+5u09lHNsj6tQ51s1SPrCBkedbNf0Tp0GbMJDyR4e9T04ZZw== phpseclib-generated-key

-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----

: http://phpseclib.sourceforge.net/rsa/examples.html#openssh

Answer 3

- ?

ssh-keygen -q -N place_your_passphrase_here -t rsa -f ~/.ssh/id_rsa

It worked for me

Answer 4

Check the man page ssh-keygento find out how to execute it without any hints.

http://linux.die.net/man/1/ssh-keygen