hash_do($h . $p . md5($this->KEY), $header['alg']);
            $sign = $h. '.' . $p . '.' . $s;
            return $sign;
        }
        return null;
    }

    public function check_token($jwt){
        if (empty($jwt)){
            return false;
        }
        $tokens = explode('.', $jwt);
        if (count($tokens)!==3){
            return false;
        }
        list($header64, $payload64, $sign) = $tokens;

        $header = json_decode(base64_decode($header64), TRUE);
        if (!isset($header['alg'])){
            return false;
        }

        $s = $this->hash_do($header64 . $payload64 . md5($this->KEY), $header['alg']);
        if ($s !== $sign){
            return false;
        }

        $payload = json_decode(base64_decode($payload64), TRUE);
        $time = time();
        if (isset($payload['iat']) && $payload['iat'] > $time){
            return false;
        }
        if (isset($payload['exp']) && $payload['exp'] < $time){
            return false;
        }
        return true;
    }

}

使用式：

public function auth_token(){
    $over = config('TOKEN_OVER_TIME'); // 生存时间
    $time = time();
    $time_over = $time + $over;
    $header = [
        'typ' => 'JWT',
        'alg' => 'HS256'
    ];
    $payload = [
        'iss' => 'admin_name',
        'iat' => $time,
        'exp' => $time_over,
        'uid' => 12 
    ];

    $j = new Jwt();
    $sign = $j->create_token($header, $payload);
    return $sign;
}





 public function check(){
 	$jwt = 'jwtxxxxxxxx';
    
 	$j = new Jwt();
    $b = $j->check_token($jwt);
 	dump($b);
 }