PHP实现DER密钥转PEM密钥

DER格式的密钥转PEM

PEM格式的密钥就是用DER格式的数据用base64进行编码后，然后在前后加上 “-----BEGIN PUBLIC KEY-----” 和 “-----END PUBLIC KEY-----”

PHP

十进制DER数据转换

$derData = 'XXXXXXXXXXXXXXXXXXXX';
$pemData = "-----BEGIN PUBLIC KEY-----
"
            . wordwrap(base64_encode($derData), 64, "
", true)
            . "
-----END PUBLIC KEY-----";

十六进制DER格式数据转换

$derData = 'XXXXXXXXXXXXXXXXXXXX';
$pemData = "-----BEGIN PUBLIC KEY-----
"
            . wordwrap(base64_encode(Hex2String($derData)), 64, "
", true)
            . "
-----END PUBLIC KEY-----";

function Hex2String($hex)
{
    $string = '';
    for ($i = 0; $i < strlen($hex) - 1; $i += 2) {
        $string .= chr(hexdec($hex[$i] . $hex[$i + 1]));
    }
    return $string;
}