From 97625b44e7ec96a99b78e910ddcfdabb687f68b3 Mon Sep 17 00:00:00 2001 From: zeripath Date: Tue, 29 Mar 2022 09:27:37 +0100 Subject: [PATCH] Provide configuration to allow camo-media proxying (#12802) * Provide configuration to allow camo-media proxying Fix #916 Signed-off-by: Andrew Thornton Co-authored-by: 6543 <6543@obermui.de> Co-authored-by: wxiaoguang --- custom/conf/app.example.ini | 17 +++++++ .../doc/advanced/config-cheat-sheet.en-us.md | 9 +++- modules/markup/camo.go | 47 +++++++++++++++++++ modules/markup/camo_test.go | 45 ++++++++++++++++++ modules/markup/html.go | 1 + modules/setting/setting.go | 15 ++++++ 6 files changed, 133 insertions(+), 1 deletion(-) create mode 100644 modules/markup/camo.go create mode 100644 modules/markup/camo_test.go diff --git a/custom/conf/app.example.ini b/custom/conf/app.example.ini index 8c6643b9b..516d61452 100644 --- a/custom/conf/app.example.ini +++ b/custom/conf/app.example.ini @@ -424,6 +424,23 @@ INTERNAL_TOKEN= ;; This cache will store the successfully hashed tokens in a LRU cache as a balance between performance and security. ;SUCCESSFUL_TOKENS_CACHE_SIZE = 20 +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +[camo] +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; +;; At the moment we only support images +;; +;; if the camo is enabled +;ENABLED = false +;; url to a camo image proxy, it **is required** if camo is enabled. +;SERVER_URL = +;; HMAC to encode urls with, it **is required** if camo is enabled. +;HMAC_KEY = +;; Set to true to use camo for https too lese only non https urls are proxyed +;ALLWAYS = false + ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; [oauth2] diff --git a/docs/content/doc/advanced/config-cheat-sheet.en-us.md b/docs/content/doc/advanced/config-cheat-sheet.en-us.md index d9018f982..ae40e0954 100644 --- a/docs/content/doc/advanced/config-cheat-sheet.en-us.md +++ b/docs/content/doc/advanced/config-cheat-sheet.en-us.md @@ -513,7 +513,14 @@ Certain queues have defaults that override the defaults set in `[queue]` (this o - spec - use one or more special characters as ``!"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~`` - off - do not check password complexity - `PASSWORD_CHECK_PWN`: **false**: Check [HaveIBeenPwned](https://haveibeenpwned.com/Passwords) to see if a password has been exposed. -- `SUCCESSFUL_TOKENS_CACHE_SIZE`: **20**: Cache successful token hashes. API tokens are stored in the DB as pbkdf2 hashes however, this means that there is a potentially significant hashing load when there are multiple API operations. This cache will store the successfully hashed tokens in a LRU cache as a balance between performance and security. +- `SUCCESSFUL_TOKENS_CACHE_SIZE`: **20**: Cache successful token hashes. API tokens are stored in the DB as pbkdf2 hashes however, this means that there is a potentially significant hashing load when there are multiple API operations. This cache will store the successfully hashed tokens in a LRU cache as a balance between performance and security. + +## Camo (`camo`) + +- `ENABLED`: **false**: Enable media proxy, we support images only at the moment. +- `SERVER_URL`: ****: url of camo server, it **is required** if camo is enabled. +- `HMAC_KEY`: ****: Provide the HMAC key for encoding urls, it **is required** if camo is enabled. +- `ALLWAYS`: **false**: Set to true to use camo for https too lese only non https urls are proxyed ## OpenID (`openid`) diff --git a/modules/markup/camo.go b/modules/markup/camo.go new file mode 100644 index 000000000..f804447f2 --- /dev/null +++ b/modules/markup/camo.go @@ -0,0 +1,47 @@ +// Copyright 2022 The Gitea Authors. All rights reserved. +// Use of this source code is governed by a MIT-style +// license that can be found in the LICENSE file. + +package markup + +import ( + "crypto/hmac" + "crypto/sha1" + "encoding/base64" + "net/url" + "strings" + + "code.gitea.io/gitea/modules/setting" + "code.gitea.io/gitea/modules/util" +) + +// CamoEncode encodes a lnk to fit with the go-camo and camo proxy links. The purposes of camo-proxy are: +// 1. Allow accessing "http://" images on a HTTPS site by using the "https://" URLs provided by camo-proxy. +// 2. Hide the visitor's real IP (protect privacy) when accessing external images. +func CamoEncode(link string) string { + if strings.HasPrefix(link, setting.Camo.ServerURL) { + return link + } + + mac := hmac.New(sha1.New, []byte(setting.Camo.HMACKey)) + _, _ = mac.Write([]byte(link)) // hmac does not return errors + macSum := b64encode(mac.Sum(nil)) + encodedURL := b64encode([]byte(link)) + + return util.URLJoin(setting.Camo.ServerURL, macSum, encodedURL) +} + +func b64encode(data []byte) string { + return strings.TrimRight(base64.URLEncoding.EncodeToString(data), "=") +} + +func camoHandleLink(link string) string { + if setting.Camo.Enabled { + lnkURL, err := url.Parse(link) + if err == nil && lnkURL.IsAbs() && !strings.HasPrefix(link, setting.AppURL) && + (setting.Camo.Allways || lnkURL.Scheme != "https") { + return CamoEncode(link) + } + } + return link +} diff --git a/modules/markup/camo_test.go b/modules/markup/camo_test.go new file mode 100644 index 000000000..cc917039d --- /dev/null +++ b/modules/markup/camo_test.go @@ -0,0 +1,45 @@ +// Copyright 2022 The Gitea Authors. All rights reserved. +// Use of this source code is governed by a MIT-style +// license that can be found in the LICENSE file. + +package markup + +import ( + "testing" + + "code.gitea.io/gitea/modules/setting" + + "github.com/stretchr/testify/assert" +) + +func TestCamoHandleLink(t *testing.T) { + setting.AppURL = "https://gitea.com" + // Test media proxy + setting.Camo.Enabled = true + setting.Camo.ServerURL = "https://image.proxy" + setting.Camo.HMACKey = "geheim" + + assert.Equal(t, + "https://gitea.com/img.jpg", + camoHandleLink("https://gitea.com/img.jpg")) + assert.Equal(t, + "https://testimages.org/img.jpg", + camoHandleLink("https://testimages.org/img.jpg")) + assert.Equal(t, + "https://image.proxy/eivin43gJwGVIjR9MiYYtFIk0mw/aHR0cDovL3Rlc3RpbWFnZXMub3JnL2ltZy5qcGc", + camoHandleLink("http://testimages.org/img.jpg")) + + setting.Camo.Allways = true + assert.Equal(t, + "https://gitea.com/img.jpg", + camoHandleLink("https://gitea.com/img.jpg")) + assert.Equal(t, + "https://image.proxy/tkdlvmqpbIr7SjONfHNgEU622y0/aHR0cHM6Ly90ZXN0aW1hZ2VzLm9yZy9pbWcuanBn", + camoHandleLink("https://testimages.org/img.jpg")) + assert.Equal(t, + "https://image.proxy/eivin43gJwGVIjR9MiYYtFIk0mw/aHR0cDovL3Rlc3RpbWFnZXMub3JnL2ltZy5qcGc", + camoHandleLink("http://testimages.org/img.jpg")) + + // Restore previous settings + setting.Camo.Enabled = false +} diff --git a/modules/markup/html.go b/modules/markup/html.go index 87d05dcab..af6ae3bf1 100644 --- a/modules/markup/html.go +++ b/modules/markup/html.go @@ -386,6 +386,7 @@ func visitNode(ctx *RenderContext, procs, textProcs []processor, node *html.Node attr.Val = util.URLJoin(prefix, attr.Val) } + attr.Val = camoHandleLink(attr.Val) node.Attr[i] = attr } } else if node.Data == "a" { diff --git a/modules/setting/setting.go b/modules/setting/setting.go index d11f3e65e..c80fc3d20 100644 --- a/modules/setting/setting.go +++ b/modules/setting/setting.go @@ -197,6 +197,13 @@ var ( PasswordCheckPwn bool SuccessfulTokensCacheSize int + Camo = struct { + Enabled bool + ServerURL string `ini:"SERVER_URL"` + HMACKey string `ini:"HMAC_KEY"` + Allways bool + }{} + // UI settings UI = struct { ExplorePagingNum int @@ -1019,6 +1026,14 @@ func loadFromConf(allowEmpty bool, extraConfig string) { log.Fatal("Failed to map API settings: %v", err) } else if err = Cfg.Section("metrics").MapTo(&Metrics); err != nil { log.Fatal("Failed to map Metrics settings: %v", err) + } else if err = Cfg.Section("camo").MapTo(&Camo); err != nil { + log.Fatal("Failed to map Camo settings: %v", err) + } + + if Camo.Enabled { + if Camo.ServerURL == "" || Camo.HMACKey == "" { + log.Fatal(`Camo settings require "SERVER_URL" and HMAC_KEY`) + } } u := *appURL