mirror of
https://github.com/mattermost/mattermost.git
synced 2025-02-25 18:55:24 -06:00
0ca8cb36b4
* MM-26425: Make URL parsing for image proxy more robust - We don't bypass protocol relative URLs. - We don't bypass hostnames with a similar prefix. https: //mattermost.atlassian.net/browse/MM-26425 ```release-note NONE ``` * fix tests and incorporate review comments * Handle opaque URLs * Fix path tests Co-authored-by: Mattermod <mattermod@users.noreply.github.com>
93 lines
2.6 KiB
Go
93 lines
2.6 KiB
Go
// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
|
|
// See LICENSE.txt for license information.
|
|
|
|
package imageproxy
|
|
|
|
import (
|
|
"crypto/hmac"
|
|
"crypto/sha1"
|
|
"encoding/hex"
|
|
"io"
|
|
"net/http"
|
|
"net/url"
|
|
)
|
|
|
|
type AtmosCamoBackend struct {
|
|
proxy *ImageProxy
|
|
siteURL *url.URL
|
|
remoteURL *url.URL
|
|
}
|
|
|
|
func makeAtmosCamoBackend(proxy *ImageProxy) *AtmosCamoBackend {
|
|
// We deliberately ignore the error because it's from config.json.
|
|
// The function returns a nil pointer in case of error, and we handle it when it's used.
|
|
siteURL, _ := url.Parse(*proxy.ConfigService.Config().ServiceSettings.SiteURL)
|
|
remoteURL, _ := url.Parse(*proxy.ConfigService.Config().ImageProxySettings.RemoteImageProxyURL)
|
|
|
|
return &AtmosCamoBackend{
|
|
proxy: proxy,
|
|
siteURL: siteURL,
|
|
remoteURL: remoteURL,
|
|
}
|
|
}
|
|
|
|
func (backend *AtmosCamoBackend) GetImage(w http.ResponseWriter, r *http.Request, imageURL string) {
|
|
http.Redirect(w, r, backend.getAtmosCamoImageURL(imageURL), http.StatusFound)
|
|
}
|
|
|
|
func (backend *AtmosCamoBackend) GetImageDirect(imageURL string) (io.ReadCloser, string, error) {
|
|
req, err := http.NewRequest("GET", backend.getAtmosCamoImageURL(imageURL), nil)
|
|
if err != nil {
|
|
return nil, "", Error{err}
|
|
}
|
|
|
|
client := backend.proxy.HTTPService.MakeClient(false)
|
|
|
|
resp, err := client.Do(req)
|
|
if err != nil {
|
|
return nil, "", Error{err}
|
|
}
|
|
|
|
// Note that we don't do any additional validation of the received data since we expect the image proxy to do that
|
|
return resp.Body, resp.Header.Get("Content-Type"), nil
|
|
}
|
|
|
|
func (backend *AtmosCamoBackend) getAtmosCamoImageURL(imageURL string) string {
|
|
cfg := *backend.proxy.ConfigService.Config()
|
|
options := *cfg.ImageProxySettings.RemoteImageProxyOptions
|
|
|
|
if imageURL == "" || backend.siteURL == nil {
|
|
return imageURL
|
|
}
|
|
|
|
// Parse url, return siteURL in case of failure.
|
|
// Also if the URL is opaque.
|
|
parsedURL, err := url.Parse(imageURL)
|
|
if err != nil || parsedURL.Opaque != "" {
|
|
return backend.siteURL.String()
|
|
}
|
|
|
|
// If host is same as siteURL host/ remoteURL host, return.
|
|
if parsedURL.Host == backend.siteURL.Host || parsedURL.Host == backend.remoteURL.Host {
|
|
return parsedURL.String()
|
|
}
|
|
|
|
// Handle protocol-relative URLs.
|
|
if parsedURL.Scheme == "" {
|
|
parsedURL.Scheme = backend.siteURL.Scheme
|
|
}
|
|
|
|
// If it's a relative URL, fill up the hostname and scheme and return.
|
|
if parsedURL.Host == "" {
|
|
parsedURL.Host = backend.siteURL.Host
|
|
return parsedURL.String()
|
|
}
|
|
|
|
urlBytes := []byte(parsedURL.String())
|
|
mac := hmac.New(sha1.New, []byte(options))
|
|
mac.Write(urlBytes)
|
|
digest := hex.EncodeToString(mac.Sum(nil))
|
|
|
|
return backend.remoteURL.String() + "/" + digest + "/" + hex.EncodeToString(urlBytes)
|
|
}
|