Returns TRUE on success or FALSE on failure.
If successful the signature is returned in
signature
.
openssl_sign() computes a signature for the
specified data
by using SHA1 for hashing
followed by encryption using the private key associated with
priv_key_id
. Note that the data itself is
not encrypted.
Note: Optional 4th parameter
signature_alg
was added in version 5.0.0. Its default value is OPENSSL_ALGO_SHA1. For more information see the list of Signature Algorithms.
See also openssl_verify().