(PHP 4 >= 4.0.4, PHP 5)
openssl_seal — Seal (encrypt) data
$data
, string &$sealed_data
, array &$env_keys
, array $pub_key_ids
[, string $method
] )
openssl_seal() seals (encrypts)
data
by using RC4 with a randomly generated
secret key. The key is encrypted with each of the public keys
associated with the identifiers in pub_key_ids
and each encrypted key is returned
in env_keys
. This means that one can send
sealed data to multiple recipients (provided one has obtained their
public keys). Each recipient must receive both the sealed data and
the envelope key that was encrypted with the recipient's public key.
data
sealed_data
env_keys
pub_key_ids
Returns the length of the sealed data on success, or FALSE
on error.
If successful the sealed data is returned in
sealed_data
, and the envelope keys in
env_keys
.
Example #1 openssl_seal() example
<?php
// $data is assumed to contain the data to be sealed
// fetch public keys for our recipients, and ready them
$fp = fopen("/src/openssl-0.9.6/demos/maurice/cert.pem", "r");
$cert = fread($fp, 8192);
fclose($fp);
$pk1 = openssl_get_publickey($cert);
// Repeat for second recipient
$fp = fopen("/src/openssl-0.9.6/demos/sign/cert.pem", "r");
$cert = fread($fp, 8192);
fclose($fp);
$pk2 = openssl_get_publickey($cert);
// seal message, only owners of $pk1 and $pk2 can decrypt $sealed with keys
// $ekeys[0] and $ekeys[1] respectively.
openssl_seal($data, $sealed, $ekeys, array($pk1, $pk2));
// free the keys from memory
openssl_free_key($pk1);
openssl_free_key($pk2);
?>