使用PHP openssl函数获取公钥长度

Question

I'm trying to get php to report the public key length of a certificate as a representation of bits.

e.g. 1024, 2048, 4096 etc.

I've trawled though countless functions on the PHP docs for answers or a steer in the right direction. Cant for the life of me work out a function that will provide this data.

http://php.net/manual/en/ref.openssl.php

openssl_pkey_get_details() seemed like the way to go. But cant find a way to give it the public key in the first place.

Currently i can parse the certificate. However this doesn't include the public key or bits information.

<?php

$cert = $_POST['cert_text'];
$ssl = openssl_x509_parse($cert);
echo json_encode($ssl);

?>

The $cert variable above is a PEM format certificate file. So in the format of

-----BEGIN CERTIFICATE-----
MIIGWTCCBUGgAwIBAgIKG6SqTwACAAAANzANBgkqhkiG.....etc..
-----END CERTIFICATE-----

Answer 1

i believe this http://php.net/manual/en/function.openssl-pkey-get-details.php will solve your problem

using

array openssl_pkey_get_details ( resource $key )

Returns an array with the key details in success or FALSE in failure. Returned array has indexes bits (number of bits), key (string representation of the public key) and type (type of the key which is one of OPENSSL_KEYTYPE_RSA, OPENSSL_KEYTYPE_DSA, OPENSSL_KEYTYPE_DH, OPENSSL_KEYTYPE_EC or -1 meaning unknown).