支付宝开发（一）－认识php openssl RSA 非对称加密实现

//需要签名的数据
$data = 'my data';

//生成私钥和公钥
$new_key_pair = openssl_pkey_new(array(
"private_key_bits" => 2048,
"private_key_type" => OPENSSL_KEYTYPE_RSA,
));
//私钥
openssl_pkey_export($new_key_pair, $private_key_pem);
//公钥
$details        = openssl_pkey_get_details($new_key_pair);
$public_key_pem = $details['key'];

//用私钥加密得到签名
openssl_sign($data, $signature, $private_key_pem, OPENSSL_ALGO_SHA256);

//save for later
file_put_contents('private_key.pem', $private_key_pem);
file_put_contents('public_key.pem', $public_key_pem);
file_put_contents('signature.dat', $signature);

//用公钥和签名数据解密验证身份
$r = openssl_verify($data, $signature, $public_key_pem, "sha256WithRSAEncryption");
var_dump($r);