Move key generation and Keychain to key pkg

Ref T613

account.go

@@ -154,7 +154,7 @@ func signupWithRegistration(app *App, signup userRegistration, w http.ResponseWr
 		Created:    time.Now().Truncate(time.Second).UTC(),
 	}
 	if signup.Email != "" {
-		encEmail, err := data.Encrypt(app.keys.emailKey, signup.Email)
+		encEmail, err := data.Encrypt(app.keys.EmailKey, signup.Email)
 		if err != nil {
 			log.Error("Unable to encrypt email: %s\n", err)
 		} else {

app.go

@@ -37,6 +37,7 @@ import (
 	"github.com/writeas/web-core/log"
 	"github.com/writeas/writefreely/author"
 	"github.com/writeas/writefreely/config"
+	"github.com/writeas/writefreely/key"
 	"github.com/writeas/writefreely/migrations"
 	"github.com/writeas/writefreely/page"
 )
@@ -69,13 +70,17 @@ type App struct {
 	db           *datastore
 	cfg          *config.Config
 	cfgFile      string
-	keys         *Keychain
+	keys         *key.Keychain
 	sessionStore *sessions.CookieStore
 	formDecoder  *schema.Decoder
 
 	timeline *localTimeline
 }
 
+func (app *App) SetKeys(k *key.Keychain) {
+	app.keys = k
+}
+
 // handleViewHome shows page at root path. Will be the Pad if logged in and the
 // catch-all landing page otherwise.
 func handleViewHome(app *App, w http.ResponseWriter, r *http.Request) error {

database.go

@@ -29,6 +29,7 @@ import (
 	"github.com/writeas/web-core/log"
 	"github.com/writeas/web-core/query"
 	"github.com/writeas/writefreely/author"
+	"github.com/writeas/writefreely/key"
 )
 
 const (
@@ -44,7 +45,7 @@ var (
 
 type writestore interface {
 	CreateUser(*User, string) error
-	UpdateUserEmail(keys *Keychain, userID int64, email string) error
+	UpdateUserEmail(keys *key.Keychain, userID int64, email string) error
 	UpdateEncryptedUserEmail(int64, []byte) error
 	GetUserByID(int64) (*User, error)
 	GetUserForAuth(string) (*User, error)
@@ -219,8 +220,8 @@ func (db *datastore) CreateUser(u *User, collectionTitle string) error {
 
 // FIXME: We're returning errors inconsistently in this file. Do we use Errorf
 // for returned value, or impart?
-func (db *datastore) UpdateUserEmail(keys *Keychain, userID int64, email string) error {
-	encEmail, err := data.Encrypt(keys.emailKey, email)
+func (db *datastore) UpdateUserEmail(keys *key.Keychain, userID int64, email string) error {
+	encEmail, err := data.Encrypt(keys.EmailKey, email)
 	if err != nil {
 		return fmt.Errorf("Couldn't encrypt email %s: %s\n", email, err)
 	}
@@ -1780,7 +1781,7 @@ func (db *datastore) ChangeSettings(app *App, u *User, s *userSettings) error {
 
 	// Update email if given
 	if s.Email != "" {
-		encEmail, err := data.Encrypt(app.keys.emailKey, s.Email)
+		encEmail, err := data.Encrypt(app.keys.EmailKey, s.Email)
 		if err != nil {
 			log.Error("Couldn't encrypt email %s: %s\n", s.Email, err)
 			return impart.HTTPError{http.StatusInternalServerError, "Unable to encrypt email address."}

key/key.go

@@ -0,0 +1,62 @@
+/*
+ * Copyright © 2019 A Bunch Tell LLC.
+ *
+ * This file is part of WriteFreely.
+ *
+ * WriteFreely is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, included
+ * in the LICENSE file in this source code package.
+ */
+
+// Package key holds application keys and utilities around generating them.
+package key
+
+import (
+	"crypto/rand"
+)
+
+const (
+	EncKeysBytes = 32
+)
+
+type Keychain struct {
+	EmailKey, CookieAuthKey, CookieKey []byte
+}
+
+// GenerateKeys generates necessary keys for the app on the given Keychain,
+// skipping any that already exist.
+func (keys *Keychain) GenerateKeys() error {
+	// Generate keys only if they don't already exist
+	var err, keyErrs error
+	if len(keys.EmailKey) == 0 {
+		keys.EmailKey, err = GenerateBytes(EncKeysBytes)
+		if err != nil {
+			keyErrs = err
+		}
+	}
+	if len(keys.CookieAuthKey) == 0 {
+		keys.CookieAuthKey, err = GenerateBytes(EncKeysBytes)
+		if err != nil {
+			keyErrs = err
+		}
+	}
+	if len(keys.CookieKey) == 0 {
+		keys.CookieKey, err = GenerateBytes(EncKeysBytes)
+		if err != nil {
+			keyErrs = err
+		}
+	}
+
+	return keyErrs
+}
+
+// GenerateBytes returns securely generated random bytes.
+func GenerateBytes(n int) ([]byte, error) {
+	b := make([]byte, n)
+	_, err := rand.Read(b)
+	if err != nil {
+		return nil, err
+	}
+
+	return b, nil
+}

keys.go

@@ -11,8 +11,8 @@
 package writefreely
 
 import (
-	"crypto/rand"
 	"github.com/writeas/web-core/log"
+	"github.com/writeas/writefreely/key"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -20,8 +20,6 @@ import (
 
 const (
 	keysDir = "keys"
-
-	encKeysBytes = 32
 )
 
 var (
@@ -30,9 +28,6 @@ var (
 	cookieKeyPath     = filepath.Join(keysDir, "cookies_enc.aes256")
 )
 
-type Keychain struct {
-	emailKey, cookieAuthKey, cookieKey []byte
-}
 
 func initKeyPaths(app *App) {
 	emailKeyPath = filepath.Join(app.cfg.Server.KeysParentDir, emailKeyPath)
@@ -42,12 +37,12 @@ func initKeyPaths(app *App) {
 
 func initKeys(app *App) error {
 	var err error
-	app.keys = &Keychain{}
+	app.keys = &key.Keychain{}
 
 	if debugging {
 		log.Info("  %s", emailKeyPath)
 	}
-	app.keys.emailKey, err = ioutil.ReadFile(emailKeyPath)
+	app.keys.EmailKey, err = ioutil.ReadFile(emailKeyPath)
 	if err != nil {
 		return err
 	}
@@ -55,7 +50,7 @@ func initKeys(app *App) error {
 	if debugging {
 		log.Info("  %s", cookieAuthKeyPath)
 	}
-	app.keys.cookieAuthKey, err = ioutil.ReadFile(cookieAuthKeyPath)
+	app.keys.CookieAuthKey, err = ioutil.ReadFile(cookieAuthKeyPath)
 	if err != nil {
 		return err
 	}
@@ -63,7 +58,7 @@ func initKeys(app *App) error {
 	if debugging {
 		log.Info("  %s", cookieKeyPath)
 	}
-	app.keys.cookieKey, err = ioutil.ReadFile(cookieKeyPath)
+	app.keys.CookieKey, err = ioutil.ReadFile(cookieKeyPath)
 	if err != nil {
 		return err
 	}
@@ -85,7 +80,7 @@ func generateKey(path string) error {
 	}
 
 	log.Info("Generating %s.", path)
-	b, err := generateBytes(encKeysBytes)
+	b, err := key.GenerateBytes(key.EncKeysBytes)
 	if err != nil {
 		log.Error("FAILED. %s. Run writefreely --gen-keys again.", err)
 		return err
@@ -98,14 +93,3 @@ func generateKey(path string) error {
 	log.Info("Success.")
 	return nil
 }
-
-// generateBytes returns securely generated random bytes.
-func generateBytes(n int) ([]byte, error) {
-	b := make([]byte, n)
-	_, err := rand.Read(b)
-	if err != nil {
-		return nil, err
-	}
-
-	return b, nil
-}

session.go

@@ -34,7 +34,7 @@ func initSession(app *App) *sessions.CookieStore {
 	gob.Register(&User{})
 
 	// Create the cookie store
-	store := sessions.NewCookieStore(app.keys.cookieAuthKey, app.keys.cookieKey)
+	store := sessions.NewCookieStore(app.keys.CookieAuthKey, app.keys.CookieKey)
 	store.Options = &sessions.Options{
 		Path:     "/",
 		MaxAge:   sessionLength,

users.go

@@ -16,6 +16,7 @@ import (
 	"github.com/guregu/null/zero"
 	"github.com/writeas/web-core/data"
 	"github.com/writeas/web-core/log"
+	"github.com/writeas/writefreely/key"
 )
 
 type (
@@ -79,13 +80,13 @@ type (
 
 // EmailClear decrypts and returns the user's email, caching it in the user
 // object.
-func (u *User) EmailClear(keys *Keychain) string {
+func (u *User) EmailClear(keys *key.Keychain) string {
 	if u.clearEmail != "" {
 		return u.clearEmail
 	}
 
 	if u.Email.Valid && u.Email.String != "" {
-		email, err := data.Decrypt(keys.emailKey, []byte(u.Email.String))
+		email, err := data.Decrypt(keys.EmailKey, []byte(u.Email.String))
 		if err != nil {
 			log.Error("Error decrypting user email: %v", err)
 		} else {