mirror of
https://codeberg.org/forgejo/forgejo.git
synced 2024-12-09 11:03:13 +01:00
5b9557aef5
Close #24062 At the beginning, I just wanted to fix the warning mentioned by #24062 But, the cookie code really doesn't look good to me, so clean up them. Complete the TODO on `SetCookie`: > TODO: Copied from gitea.com/macaron/macaron and should be improved after macaron removed.
242 lines
7 KiB
Go
242 lines
7 KiB
Go
// Copyright 2013 Martini Authors
|
|
// Copyright 2014 The Macaron Authors
|
|
// Copyright 2021 The Gitea Authors
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License"): you may
|
|
// not use this file except in compliance with the License. You may obtain
|
|
// a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
// License for the specific language governing permissions and limitations
|
|
// under the License.
|
|
// SPDX-License-Identifier: Apache-2.0
|
|
|
|
// a middleware that generates and validates CSRF tokens.
|
|
|
|
package context
|
|
|
|
import (
|
|
"encoding/base32"
|
|
"fmt"
|
|
"net/http"
|
|
"strconv"
|
|
"time"
|
|
|
|
"code.gitea.io/gitea/modules/log"
|
|
"code.gitea.io/gitea/modules/setting"
|
|
"code.gitea.io/gitea/modules/util"
|
|
"code.gitea.io/gitea/modules/web/middleware"
|
|
)
|
|
|
|
// CSRFProtector represents a CSRF protector and is used to get the current token and validate the token.
|
|
type CSRFProtector interface {
|
|
// GetHeaderName returns HTTP header to search for token.
|
|
GetHeaderName() string
|
|
// GetFormName returns form value to search for token.
|
|
GetFormName() string
|
|
// GetToken returns the token.
|
|
GetToken() string
|
|
// Validate validates the token in http context.
|
|
Validate(ctx *Context)
|
|
// DeleteCookie deletes the cookie
|
|
DeleteCookie(ctx *Context)
|
|
}
|
|
|
|
type csrfProtector struct {
|
|
opt CsrfOptions
|
|
// Token generated to pass via header, cookie, or hidden form value.
|
|
Token string
|
|
// This value must be unique per user.
|
|
ID string
|
|
}
|
|
|
|
// GetHeaderName returns the name of the HTTP header for csrf token.
|
|
func (c *csrfProtector) GetHeaderName() string {
|
|
return c.opt.Header
|
|
}
|
|
|
|
// GetFormName returns the name of the form value for csrf token.
|
|
func (c *csrfProtector) GetFormName() string {
|
|
return c.opt.Form
|
|
}
|
|
|
|
// GetToken returns the current token. This is typically used
|
|
// to populate a hidden form in an HTML template.
|
|
func (c *csrfProtector) GetToken() string {
|
|
return c.Token
|
|
}
|
|
|
|
// CsrfOptions maintains options to manage behavior of Generate.
|
|
type CsrfOptions struct {
|
|
// The global secret value used to generate Tokens.
|
|
Secret string
|
|
// HTTP header used to set and get token.
|
|
Header string
|
|
// Form value used to set and get token.
|
|
Form string
|
|
// Cookie value used to set and get token.
|
|
Cookie string
|
|
// Cookie domain.
|
|
CookieDomain string
|
|
// Cookie path.
|
|
CookiePath string
|
|
CookieHTTPOnly bool
|
|
// SameSite set the cookie SameSite type
|
|
SameSite http.SameSite
|
|
// Key used for getting the unique ID per user.
|
|
SessionKey string
|
|
// oldSessionKey saves old value corresponding to SessionKey.
|
|
oldSessionKey string
|
|
// If true, send token via X-Csrf-Token header.
|
|
SetHeader bool
|
|
// If true, send token via _csrf cookie.
|
|
SetCookie bool
|
|
// Set the Secure flag to true on the cookie.
|
|
Secure bool
|
|
// Disallow Origin appear in request header.
|
|
Origin bool
|
|
// Cookie lifetime. Default is 0
|
|
CookieLifeTime int
|
|
}
|
|
|
|
func prepareDefaultCsrfOptions(opt CsrfOptions) CsrfOptions {
|
|
if opt.Secret == "" {
|
|
randBytes, err := util.CryptoRandomBytes(8)
|
|
if err != nil {
|
|
// this panic can be handled by the recover() in http handlers
|
|
panic(fmt.Errorf("failed to generate random bytes: %w", err))
|
|
}
|
|
opt.Secret = base32.StdEncoding.EncodeToString(randBytes)
|
|
}
|
|
if opt.Header == "" {
|
|
opt.Header = "X-Csrf-Token"
|
|
}
|
|
if opt.Form == "" {
|
|
opt.Form = "_csrf"
|
|
}
|
|
if opt.Cookie == "" {
|
|
opt.Cookie = "_csrf"
|
|
}
|
|
if opt.CookiePath == "" {
|
|
opt.CookiePath = "/"
|
|
}
|
|
if opt.SessionKey == "" {
|
|
opt.SessionKey = "uid"
|
|
}
|
|
if opt.CookieLifeTime == 0 {
|
|
opt.CookieLifeTime = int(CsrfTokenTimeout.Seconds())
|
|
}
|
|
|
|
opt.oldSessionKey = "_old_" + opt.SessionKey
|
|
return opt
|
|
}
|
|
|
|
func newCsrfCookie(c *csrfProtector, value string) *http.Cookie {
|
|
return &http.Cookie{
|
|
Name: c.opt.Cookie,
|
|
Value: value,
|
|
Path: c.opt.CookiePath,
|
|
Domain: c.opt.CookieDomain,
|
|
MaxAge: c.opt.CookieLifeTime,
|
|
Secure: c.opt.Secure,
|
|
HttpOnly: c.opt.CookieHTTPOnly,
|
|
SameSite: c.opt.SameSite,
|
|
}
|
|
}
|
|
|
|
// PrepareCSRFProtector returns a CSRFProtector to be used for every request.
|
|
// Additionally, depending on options set, generated tokens will be sent via Header and/or Cookie.
|
|
func PrepareCSRFProtector(opt CsrfOptions, ctx *Context) CSRFProtector {
|
|
opt = prepareDefaultCsrfOptions(opt)
|
|
x := &csrfProtector{opt: opt}
|
|
|
|
if opt.Origin && len(ctx.Req.Header.Get("Origin")) > 0 {
|
|
return x
|
|
}
|
|
|
|
x.ID = "0"
|
|
uidAny := ctx.Session.Get(opt.SessionKey)
|
|
if uidAny != nil {
|
|
switch uidVal := uidAny.(type) {
|
|
case string:
|
|
x.ID = uidVal
|
|
case int64:
|
|
x.ID = strconv.FormatInt(uidVal, 10)
|
|
default:
|
|
log.Error("invalid uid type in session: %T", uidAny)
|
|
}
|
|
}
|
|
|
|
oldUID := ctx.Session.Get(opt.oldSessionKey)
|
|
uidChanged := oldUID == nil || oldUID.(string) != x.ID
|
|
cookieToken := ctx.GetSiteCookie(opt.Cookie)
|
|
|
|
needsNew := true
|
|
if uidChanged {
|
|
_ = ctx.Session.Set(opt.oldSessionKey, x.ID)
|
|
} else if cookieToken != "" {
|
|
// If cookie token presents, re-use existing unexpired token, else generate a new one.
|
|
if issueTime, ok := ParseCsrfToken(cookieToken); ok {
|
|
dur := time.Since(issueTime) // issueTime is not a monotonic-clock, the server time may change a lot to an early time.
|
|
if dur >= -CsrfTokenRegenerationInterval && dur <= CsrfTokenRegenerationInterval {
|
|
x.Token = cookieToken
|
|
needsNew = false
|
|
}
|
|
}
|
|
}
|
|
|
|
if needsNew {
|
|
// FIXME: actionId.
|
|
x.Token = GenerateCsrfToken(x.opt.Secret, x.ID, "POST", time.Now())
|
|
if opt.SetCookie {
|
|
cookie := newCsrfCookie(x, x.Token)
|
|
ctx.Resp.Header().Add("Set-Cookie", cookie.String())
|
|
}
|
|
}
|
|
|
|
if opt.SetHeader {
|
|
ctx.Resp.Header().Add(opt.Header, x.Token)
|
|
}
|
|
return x
|
|
}
|
|
|
|
func (c *csrfProtector) validateToken(ctx *Context, token string) {
|
|
if !ValidCsrfToken(token, c.opt.Secret, c.ID, "POST", time.Now()) {
|
|
c.DeleteCookie(ctx)
|
|
if middleware.IsAPIPath(ctx.Req) {
|
|
// currently, there should be no access to the APIPath with CSRF token. because templates shouldn't use the `/api/` endpoints.
|
|
http.Error(ctx.Resp, "Invalid CSRF token.", http.StatusBadRequest)
|
|
} else {
|
|
ctx.Flash.Error(ctx.Tr("error.invalid_csrf"))
|
|
ctx.Redirect(setting.AppSubURL + "/")
|
|
}
|
|
}
|
|
}
|
|
|
|
// Validate should be used as a per route middleware. It attempts to get a token from an "X-Csrf-Token"
|
|
// HTTP header and then a "_csrf" form value. If one of these is found, the token will be validated.
|
|
// If this validation fails, custom Error is sent in the reply.
|
|
// If neither a header nor form value is found, http.StatusBadRequest is sent.
|
|
func (c *csrfProtector) Validate(ctx *Context) {
|
|
if token := ctx.Req.Header.Get(c.GetHeaderName()); token != "" {
|
|
c.validateToken(ctx, token)
|
|
return
|
|
}
|
|
if token := ctx.Req.FormValue(c.GetFormName()); token != "" {
|
|
c.validateToken(ctx, token)
|
|
return
|
|
}
|
|
c.validateToken(ctx, "") // no csrf token, use an empty token to respond error
|
|
}
|
|
|
|
func (c *csrfProtector) DeleteCookie(ctx *Context) {
|
|
if c.opt.SetCookie {
|
|
cookie := newCsrfCookie(c, "")
|
|
cookie.MaxAge = -1
|
|
ctx.Resp.Header().Add("Set-Cookie", cookie.String())
|
|
}
|
|
}
|