openssl_public_decrypt() decrypts data that was previous encrypted via openssl_private_encrypt() and stores the result into decrypted. key must be the public key corresponding that was used to encrypt the data. padding defaults to OPENSSL_PKCS1_PADDING, but can also be OPENSSL_NO_PADDING.
Returns TRUE on success or FALSE on failure.
You can use this function e.g. to check if the message was written by the owner of the private key.
See also openssl_private_encrypt() and openssl_private_decrypt().