openssl_verify

openssl_verify

Verify signature

 **openssl_verify** string $data string $signature  $public_key  $algorithm int $padding

verifies that the
is correct for the specified
using the public key associated with

. This must be the public key corresponding to the private key used for signing. openssl_verify``signature``data``public_key

dataThe string of data used to generate the signature previously

signature A raw binary string, generated by or similar means openssl_sign

public_key - a key, returned by OpenSSLAsymmetricKey``openssl_get_publickey

    - a  formatted key (e.g. )
  `string``-----BEGIN PUBLIC KEY-----

MIIBCgK...`

algorithm - one of these . intSignature Algorithms

    - a valid string returned by  example, "sha1WithRSAEncryption" or "sha512".
  `string``openssl_get_md_methods`

paddingRSA PSS padding to use.

Returns 1 if the signature is correct, 0 if it is incorrect, and -1 or false on error.

Voorbeeld: 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 ($ok == 0) {
    echo "bad";
} else {
    echo "ugly, error checking signature";
}
// free the key from memory
openssl_free_key($pubkeyid);
?>

Voorbeeld: 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 signature
openssl_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();
}
?>

openssl_sign