From 887ed241d64ba5db3fd3d87194fb5595e5ad7d73 Mon Sep 17 00:00:00 2001
From: r <r@freesoftwareextremist.com>
Date: Tue, 25 Oct 2022 13:40:49 +0000
Subject: Use cookies for session storage

Remove the server side session storage and store all the session related data
in the client side cookies. This decreases the exposure of the auth tokens.
It also simplifies the installation process as bloat no longer requires write
access to the filesystem.

This is a breaking change, all the existing sessions will stop working.
---
 service/client.go | 111 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 111 insertions(+)
 create mode 100644 service/client.go

(limited to 'service/client.go')

diff --git a/service/client.go b/service/client.go
new file mode 100644
index 0000000..3affd57
--- /dev/null
+++ b/service/client.go
@@ -0,0 +1,111 @@
+package service
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"net/http"
+	"strings"
+	"time"
+
+	"bloat/mastodon"
+	"bloat/model"
+	"bloat/renderer"
+)
+
+type client struct {
+	*mastodon.Client
+	w    http.ResponseWriter
+	r    *http.Request
+	s    *model.Session
+	csrf string
+	ctx  context.Context
+	rctx *renderer.Context
+}
+
+func (c *client) setSession(sess *model.Session) error {
+	var sb strings.Builder
+	bw := base64.NewEncoder(base64.URLEncoding, &sb)
+	err := json.NewEncoder(bw).Encode(sess)
+	bw.Close()
+	if err != nil {
+		return err
+	}
+	http.SetCookie(c.w, &http.Cookie{
+		Name:    "session",
+		Value:   sb.String(),
+		Expires: time.Now().Add(365 * 24 * time.Hour),
+	})
+	return nil
+}
+
+func (c *client) getSession() (sess *model.Session, err error) {
+	cookie, _ := c.r.Cookie("session")
+	if cookie == nil {
+		return nil, errInvalidSession
+	}
+	br := base64.NewDecoder(base64.URLEncoding, strings.NewReader(cookie.Value))
+	err = json.NewDecoder(br).Decode(&sess)
+	return
+}
+
+func (c *client) unsetSession() {
+	http.SetCookie(c.w, &http.Cookie{
+		Name:    "session",
+		Value:   "",
+		Expires: time.Now(),
+	})
+}
+
+func (c *client) writeJson(data interface{}) error {
+	return json.NewEncoder(c.w).Encode(map[string]interface{}{
+		"data": data,
+	})
+}
+
+func (c *client) redirect(url string) {
+	c.w.Header().Add("Location", url)
+	c.w.WriteHeader(http.StatusFound)
+}
+
+func (c *client) authenticate(t int) (err error) {
+	csrf := c.r.FormValue("csrf_token")
+	ref := c.r.URL.RequestURI()
+	defer func() {
+		if c.s == nil {
+			c.s = &model.Session{
+				Settings: *model.NewSettings(),
+			}
+		}
+		c.rctx = &renderer.Context{
+			HideAttachments:  c.s.Settings.HideAttachments,
+			MaskNSFW:         c.s.Settings.MaskNSFW,
+			ThreadInNewTab:   c.s.Settings.ThreadInNewTab,
+			FluorideMode:     c.s.Settings.FluorideMode,
+			DarkMode:         c.s.Settings.DarkMode,
+			CSRFToken:        c.s.CSRFToken,
+			UserID:           c.s.UserID,
+			AntiDopamineMode: c.s.Settings.AntiDopamineMode,
+			UserCSS:          c.s.Settings.CSS,
+			Referrer:         ref,
+		}
+	}()
+	if t < SESSION {
+		return
+	}
+	sess, err := c.getSession()
+	if err != nil {
+		return err
+	}
+	c.s = sess
+	c.Client = mastodon.NewClient(&mastodon.Config{
+		Server:       "https://" + c.s.Instance,
+		ClientID:     c.s.ClientID,
+		ClientSecret: c.s.ClientSecret,
+		AccessToken:  c.s.AccessToken,
+	})
+	if t >= CSRF && (len(csrf) < 1 || csrf != c.s.CSRFToken) {
+		return errInvalidCSRFToken
+	}
+	return
+}
-- 
cgit v1.2.3