PHP使用RSA验证JWT

<?php

function base64_url_json_encode($data, $json = true)
{
    $data = $json ? json_encode($data) : $data;
    return str_replace(['+', '/', '='], ['-', '_', ''], base64_encode($data));
}

function base64_url_json_decode($data, $json = true)
{
    $data = str_replace(['-', '_'], ['+', '/'], $data);
    $data .= str_repeat('=', 4 - strlen($data) % 4);
    $bd = base64_decode($data);
    return $json ? json_decode($bd, true) : $bd;
}

$pub_pem = '-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAu1SU1LfVLPHCozMxH2Mo
4lgOEePzNm0tRgeLezV6ffAt0gunVTLw7onLRnrq0/IzW7yWR7QkrmBL7jTKEn5u
+qKhbwKfBstIs+bMY2Zkp18gnTxKLxoS2tFczGkPLPgizskuemMghRniWaoLcyeh
kd3qqGElvW/VDL5AaWTg0nLVkjRo9z+40RQzuVaE8AkAFmxZzow3x+VJYKdjykkJ
0iT9wCS0DRTXu269V264Vf/3jvredZiKRkgwlL9xNAwxXFg0x/XFw005UWVRIkdg
cKWTjpBP2dPwVZ4WWC+9aGVd+Gyn1o0CLelf4rEjGoXbAAEgAqeGUxrcIlbjXfbc
mwIDAQAB
-----END PUBLIC KEY-----';

$pri_pem = '-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----';


$pub = openssl_get_publickey($pub_pem);
$pri = openssl_get_privatekey($pri_pem);

$jwt = 'eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiYWRtaW4iOnRydWUsImlhdCI6MTUxNjIzOTAyMn0.NHVaYe26MbtOYhSKkoKYdFVomg4i8ZJd8_-RU8VNbftc4TSMb4bXP3l3YlNWACwyXPGffz5aXHc6lty1Y2t4SWRqGteragsVdZufDn5BlnJl9pdR_kdVFUsra2rWKEofkZeIC4yWytE58sMIihvo9H1ScmmVwBcQP6XETqYd0aSHp1gOa9RdUPDvoXQ5oqygTqVtxaDr6wUFKrKItgBMzWIdNZ6y7O9E0DhEPTbE9rfBo6KTFsHAZnMg4k68CDp2woYIaXbmYTWcvbzIuHO7_37GT79XdIwkm95QJ7hYC9RiwrV7mesbY4PAahERJawntho0my942XheVLmGwLMBkQ';

[$header, $payload, $sign] = explode(".", $jwt);

$header_data = base64_url_json_decode($header);

$algo = $header_data['alg'];
$openssl_algo_map = [
    'RS384' => OPENSSL_ALGO_SHA384,
    'RS256' => OPENSSL_ALGO_SHA256,
];

$openssl_algo = $openssl_algo_map[$algo];

$verrs = openssl_verify("$header.$payload", base64_url_json_decode($sign, false), $pub, $openssl_algo);

echo "算法: $algo, 结果=1为通过: $verrs\n";


echo "\n=====以上为验证=====\n=====以下为签名=====\n\n";

// 使用上方的header, 重新生成数据
$payload_data = [
    'sub' => 'RAND',
    'username' => 'test1',
    'ts' => time(),
];
$payload = base64_url_json_encode($payload_data);

$sign_rs = openssl_sign("$header.$payload", $sign_raw, $pri, $openssl_algo);

printf("签名结果: %s\n", $sign_rs ? "成功" : "失败");
if ($sign_rs) {
    $jwt_token =  "$header.$payload." . base64_url_json_encode($sign_raw, false);

    echo $jwt_token;

    printf("\n\n访问以下地址验证:  https://jwt.io/#debugger-io?%s\n", http_build_query(['token' => $jwt_token, 'publicKey' => $pub_pem]));
}