enterprise/stages: Add MTLS stage (#14296)

* prepare client auth with inbuilt server

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* introduce better IPC auth

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* init

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* start stage

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* only allow trusted proxies to set MTLS headers

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* more stage progress

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* dont fail if ipc_key doesn't exist

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* actually install app

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* fix

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* add some tests

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* update API

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* fix unquote

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* fix int serial number not jsonable

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* init ui

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* add UI

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* unrelated: fix git pull in makefile

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* fix parse helper

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* add test for outpost

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* more tests and improvements

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* improve labels

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* add support for multiple CAs on brand

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* add support for multiple CAs to MTLS stage

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* dont log ipcuser secret views

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

* fix go mod

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

---------

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

internal/outpost/rac/connection/connection.go

@@ -61,7 +61,7 @@ func (c *Connection) initSocket(forChannel string) error {
 
 	header := http.Header{
 		"Authorization": []string{authHeader},
-		"User-Agent":    []string{constants.OutpostUserAgent()},
+		"User-Agent":    []string{constants.UserAgentOutpost()},
 	}
 
 	dialer := websocket.Dialer{