28 lines
		
	
	
		
			819 B
		
	
	
	
		
			Go
		
	
	
	
			
		
		
	
	
			28 lines
		
	
	
		
			819 B
		
	
	
	
		
			Go
		
	
	
	
// Copyright 2023 The Gitea Authors. All rights reserved.
 | 
						|
// SPDX-License-Identifier: MIT
 | 
						|
 | 
						|
package httplib
 | 
						|
 | 
						|
import (
 | 
						|
	"net/url"
 | 
						|
	"strings"
 | 
						|
 | 
						|
	"code.gitea.io/gitea/modules/setting"
 | 
						|
)
 | 
						|
 | 
						|
// IsRiskyRedirectURL returns true if the URL is considered risky for redirects
 | 
						|
func IsRiskyRedirectURL(s string) bool {
 | 
						|
	// Unfortunately browsers consider a redirect Location with preceding "//", "\\", "/\" and "\/" as meaning redirect to "http(s)://REST_OF_PATH"
 | 
						|
	// Therefore we should ignore these redirect locations to prevent open redirects
 | 
						|
	if len(s) > 1 && (s[0] == '/' || s[0] == '\\') && (s[1] == '/' || s[1] == '\\') {
 | 
						|
		return true
 | 
						|
	}
 | 
						|
 | 
						|
	u, err := url.Parse(s)
 | 
						|
	if err != nil || ((u.Scheme != "" || u.Host != "") && !strings.HasPrefix(strings.ToLower(s), strings.ToLower(setting.AppURL))) {
 | 
						|
		return true
 | 
						|
	}
 | 
						|
 | 
						|
	return false
 | 
						|
}
 |