GODT-1650: Send extras

internal/bridge/smtp_backend.go

@@ -2,30 +2,36 @@ package bridge
 
 import (
 	"crypto/subtle"
+	"strings"
 	"sync"
 
 	"github.com/ProtonMail/proton-bridge/v2/internal/user"
-	"github.com/bradenaw/juniper/xslices"
 	"github.com/emersion/go-smtp"
 	"golang.org/x/exp/slices"
 )
 
 type smtpBackend struct {
-	users     []*user.User
+	users     map[string]*user.User
 	usersLock sync.RWMutex
 }
 
 func newSMTPBackend() (*smtpBackend, error) {
-	return &smtpBackend{}, nil
+	return &smtpBackend{
+		users: make(map[string]*user.User),
+	}, nil
 }
 
-func (backend *smtpBackend) Login(state *smtp.ConnectionState, username, password string) (smtp.Session, error) {
+func (backend *smtpBackend) Login(state *smtp.ConnectionState, email, password string) (smtp.Session, error) {
 	backend.usersLock.RLock()
 	defer backend.usersLock.RUnlock()
 
 	for _, user := range backend.users {
-		if slices.Contains(user.Emails(), username) && subtle.ConstantTimeCompare(user.BridgePass(), []byte(password)) == 1 {
-			return user.NewSMTPSession(username), nil
+		if subtle.ConstantTimeCompare(user.BridgePass(), []byte(password)) != 1 {
+			continue
+		}
+
+		if email := strings.ToLower(email); slices.Contains(user.Emails(), email) {
+			return user.NewSMTPSession(email)
 		}
 	}
 
@@ -38,17 +44,15 @@ func (backend *smtpBackend) AnonymousLogin(state *smtp.ConnectionState) (smtp.Se
 
 // addUser adds the given user to the backend.
 // It returns an error if a user with the same ID already exists.
-func (backend *smtpBackend) addUser(user *user.User) error {
+func (backend *smtpBackend) addUser(newUser *user.User) error {
 	backend.usersLock.Lock()
 	defer backend.usersLock.Unlock()
 
-	for _, u := range backend.users {
-		if u.ID() == user.ID() {
-			return ErrUserAlreadyExists
-		}
+	if _, ok := backend.users[newUser.ID()]; ok {
+		return ErrUserAlreadyExists
 	}
 
-	backend.users = append(backend.users, user)
+	backend.users[newUser.ID()] = newUser
 
 	return nil
 }
@@ -59,13 +63,11 @@ func (backend *smtpBackend) removeUser(user *user.User) error {
 	backend.usersLock.Lock()
 	defer backend.usersLock.Unlock()
 
-	idx := xslices.Index(backend.users, user)
-
-	if idx < 0 {
+	if _, ok := backend.users[user.ID()]; !ok {
 		return ErrNoSuchUser
 	}
 
-	backend.users = append(backend.users[:idx], backend.users[idx+1:]...)
+	delete(backend.users, user.ID())
 
 	return nil
 }