javascript - How to add csrf protection to a spa that is regarded as a static resource?

Recently I am using react+react-router to develop spa, and I use yii2 in the background. nignx is set to return index.html when 404. But one problem with this situation is that I cannot use the protection of csrf. How to solve this situation?

I saw a website using a technology stack similar to mine. I saw that it wrote a meta tag containing the token value on the head tag, and every request it made would use this token as The value of header is sent back. How to do this? How to render the token value into this index.html?

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Recently I am using react+react-router to develop spa, and the backend is yii2. nignx is set to return index.html when 404. But one problem with this situation is that I cannot use the protection of csrf. How to solve this situation?

I saw a website using a technology stack similar to mine. I saw that it wrote a meta tag containing the token value on the head tag, and every request it made would use this token as The value of header is sent back. How to do this? How to render the token value into this index.html?

Submitted by

ajax

$.ajax({
url: 你的url
type：依什么方式
dataType:数据类型
data :
headers:{'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content') ? $('meta[name="csrf-token"]').attr('content') : ''},
beforeSend:function(msg){
alert('等待回调');
},
})

Put the output part in the header

getRequest()->isPost()) {
// |            
// |        try {
// |            ##验证TOKEN  
// |            NoCSRF::check( 'csrf_token', $_POST, true, 60*10, false ); //60*10为10分钟(null为不验证时间)
// |            $result = 'CSRF check passed. Form parsed.';
// |            //$this->getRequest()->getPost('field');
// |            echo $result;       
// |        } catch ( Exception $e ) {
// |            echo $e->getMessage() . ' Form ignored.'; 
// |        }      
// |    } else {   
// |        #生成TOKEN  
// |        $token = NoCSRF::generate( 'csrf_token' );
// |        $this->getView()->assign('token', $token);
// |        $this->getView()->display('页面');
// |    }
// |    // 前端
// |    
// +----------------------------------------------------------------------

class NoCSRF
{
    protected static $doOriginCheck = false;
    /**
     * Check CSRF tokens match between session and $origin. 
     * Make sure you generated a token in the form before checking it.
     *
     * @param String $key The session and $origin key where to find the token.
     * @param Mixed $origin The object/associative array to retreive the token data from (usually $_POST).
     * @param Boolean $throwException (Facultative) TRUE to throw exception on check fail, FALSE or default to return false.
     * @param Integer $timespan (Facultative) Makes the token expire after $timespan seconds. (null = never)
     * @param Boolean $multiple (Facultative) Makes the token reusable and not one-time. (Useful for ajax-heavy requests).
     * 
     * @return Boolean Returns FALSE if a CSRF attack is detected, TRUE otherwise.
     */
    public static function check( $key, $origin, $throwException=false, $timespan=null, $multiple=false )
    {
        $session = Session::getInstance();

        if ( !$session->has( 'csrf_' . $key ) )
            if($throwException)
                throw new \Exception( 'Missing CSRF session token.' );
            else
                return false;
            
        if ( !isset( $origin[ $key ] ) )
            if($throwException)
                throw new \Exception( 'Missing CSRF form token.' );
            else
                return false;

        // Get valid token from session
        $hash = $session->get('csrf_' . $key);
        
        // Free up session token for one-time CSRF token usage.
        if(!$multiple)
            $session->forget('csrf_' . $key);

        // Origin checks
        if( self::$doOriginCheck && sha1( $_SERVER['REMOTE_ADDR'] . $_SERVER['HTTP_USER_AGENT'] ) != substr( base64_decode( $hash ), 10, 40 ) )
        {
            if($throwException)
                throw new \Exception( 'Form origin does not match token origin.' );
            else
                return false;
        }
        
        // Check if session token matches form token
        if ( $origin[ $key ] != $hash )
            if($throwException)
                throw new \Exception( 'Invalid CSRF token.' );
            else
                return false;

        // Check for token expiration
        if ( $timespan != null && is_int( $timespan ) && intval( substr( base64_decode( $hash ), 0, 10 ) ) + $timespan < time() )
            if($throwException)
                throw new \Exception( 'CSRF token has expired.' );
            else
                return false;

        return true;
    }

    /**
     * Adds extra useragent and remote_addr checks to CSRF protections.
     */
    public static function enableOriginCheck()
    {
        self::$doOriginCheck = true;
    }

    /**
     * CSRF token generation method. After generating the token, put it inside a hidden form field named $key.
     *
     * @param String $key The session key where the token will be stored. (Will also be the name of the hidden field name)
     * @return String The generated, base64 encoded token.
     */
    public static function generate( $key )
    {
        $session = Session::getInstance();

        $extra = self::$doOriginCheck ? sha1( $_SERVER['REMOTE_ADDR'] . $_SERVER['HTTP_USER_AGENT'] ) : '';
        // token generation (basically base64_encode any random complex string, time() is used for token expiration) 
        $token = base64_encode( time() . $extra . self::randomString( 32 ) );
        // store the one-time token in session
        $session->put('csrf_' . $key, $token);

        return $token;
    }

    /**
     * Generates a random string of given $length.
     *
     * @param Integer $length The string length.
     * @return String The randomly generated string.
     */
    protected static function randomString( $length )
    {
        $seed = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijqlmnopqrtsuvwxyz0123456789';
        $max = strlen( $seed ) - 1;

        $string = '';
        for ( $i = 0; $i < $length; ++$i )
            $string .= $seed{intval( mt_rand( 0.0, $max ) )};

        return $string;
    }

}
?>