Php/docs/function.openssl-verify
openssl_verify
(PHP 4 >= 4.0.4, PHP 5, PHP 7)
openssl_verify — Verify signature
Description
openssl_verify
( string $data
, string $signature
, mixed $pub_key_id
[, mixed $signature_alg = OPENSSL_ALGO_SHA1
] ) : int
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.
Parameters
dataThe string of data used to generate the signature previously
signatureA raw binary string, generated by openssl_sign() or similar means
pub_key_idresource - a key, returned by openssl_get_publickey()
string - a PEM formatted key, example, "-----BEGIN PUBLIC KEY----- MIIBCgK..."
signature_algint - one of these Signature Algorithms.
string - a valid string returned by openssl_get_md_methods() example, "sha1WithRSAEncryption" or "sha512".
Return Values
Returns 1 if the signature is correct, 0 if it is incorrect, and -1 on error.
Examples
Example #1 openssl_verify() example
<?php// $data and $signature are assumed to contain the data and the signature// fetch public key from certificate and ready it$pubkeyid = openssl_pkey_get_public("file://src/openssl-0.9.6/demos/sign/cert.pem");// state whether signature is okay or not$ok = openssl_verify($data, $signature, $pubkeyid);if ($ok == 1) { echo "good";} elseif ($ok == 0) { echo "bad";} else { echo "ugly, error checking signature";}// free the key from memoryopenssl_free_key($pubkeyid);?>
Example #2 openssl_verify() example
<?php//data you want to sign$data = 'my data';//create new private and public key$private_key_res = openssl_pkey_new(array( "private_key_bits" => 2048, "private_key_type" => OPENSSL_KEYTYPE_RSA,));$details = openssl_pkey_get_details($private_key_res);$public_key_res = openssl_pkey_get_public($details['key']);//create signatureopenssl_sign($data, $signature, $private_key_res, "sha256WithRSAEncryption");//verify signature$ok = openssl_verify($data, $signature, $public_key_res, OPENSSL_ALGO_SHA256);if ($ok == 1) { echo "valid";} elseif ($ok == 0) { echo "invalid";} else { echo "error: ".openssl_error_string();}?>
