openssl_verify Verify signature intopenssl_verify stringdata stringsignature mixedpub_key_id intsignature_alg Returns 1 if the signature is correct, 0 if it is incorrect, and -1 on error. openssl_verify verifies that the signature is correct for the specified data using the public key associated with pub_key_id. This must be the public key corresponding to the private key used for signing. Optional 4th parameter signature_alg was added in version 5.2.0. Its default value is OPENSSL_ALGO_SHA1. For more information see the list of Signature Algorithms. ]]> See also openssl_sign.