release: prepare v1.2.29

apps/api/internal/app/admin_handlers.go

@@ -49,9 +49,9 @@ func (a *App) handleAdminOverview(w http.ResponseWriter, r *http.Request) {
 }
 
 func (a *App) handleListUsers(w http.ResponseWriter, r *http.Request) {
-	rows, err := a.db.QueryContext(r.Context(), `SELECT u.id,u.login_name,u.email,u.display_name,u.role,u.disabled,u.two_factor_enabled,u.mailbox_limit_override,u.created_at,COUNT(mb.id),COALESCE(GROUP_CONCAT(mb.address), '')
+	rows, err := a.db.QueryContext(r.Context(), `SELECT u.id,u.login_name,u.email,u.display_name,u.role,u.disabled,u.two_factor_enabled,u.mailbox_limit_override,u.storage_quota_mb,u.created_at,COUNT(mb.id),COALESCE(GROUP_CONCAT(mb.address), '')
 		FROM users u LEFT JOIN mailboxes mb ON mb.user_id=u.id
-		GROUP BY u.id,u.login_name,u.email,u.display_name,u.role,u.disabled,u.two_factor_enabled,u.mailbox_limit_override,u.created_at
+		GROUP BY u.id,u.login_name,u.email,u.display_name,u.role,u.disabled,u.two_factor_enabled,u.mailbox_limit_override,u.storage_quota_mb,u.created_at
 		ORDER BY CASE WHEN u.role='admin' THEN 0 ELSE 1 END, lower(COALESCE(NULLIF(u.email,''),u.login_name)), lower(u.display_name), u.created_at`)
 	if err != nil {
 		respondError(w, http.StatusInternalServerError, "failed to list users")
@@ -64,7 +64,7 @@ func (a *App) handleListUsers(w http.ResponseWriter, r *http.Request) {
 		var disabled, twoFactorEnabled int
 		var mailboxLimitOverride sql.NullInt64
 		var created, mailboxCSV string
-		if err := rows.Scan(&item.ID, &item.LoginName, &item.Email, &item.DisplayName, &item.Role, &disabled, &twoFactorEnabled, &mailboxLimitOverride, &created, &item.MailboxCount, &mailboxCSV); err != nil {
+		if err := rows.Scan(&item.ID, &item.LoginName, &item.Email, &item.DisplayName, &item.Role, &disabled, &twoFactorEnabled, &mailboxLimitOverride, &item.StorageQuotaMB, &created, &item.MailboxCount, &mailboxCSV); err != nil {
 			respondError(w, http.StatusInternalServerError, "failed to scan users")
 			return
 		}
@@ -101,6 +101,7 @@ func (a *App) handleCreateUser(w http.ResponseWriter, r *http.Request) {
 		Password             string   `json:"password"`
 		Disabled             bool     `json:"disabled"`
 		MailboxLimitOverride *int     `json:"mailboxLimitOverride"`
+		StorageQuotaMB       int      `json:"storageQuotaMb"`
 		PermissionGroupIDs   []string `json:"permissionGroupIds"`
 	}
 	if err := decodeJSON(r, &req); err != nil {
@@ -142,6 +143,14 @@ func (a *App) handleCreateUser(w http.ResponseWriter, r *http.Request) {
 	if role == "admin" {
 		mailboxLimitOverride = nil
 	}
+	storageQuotaMB := req.StorageQuotaMB
+	if storageQuotaMB > 0 && storageQuotaMB < minimumStorageQuotaMB {
+		badRequest(w, errors.New("共享存储容量不能小于 100 MB"))
+		return
+	}
+	if storageQuotaMB == 0 {
+		storageQuotaMB = defaultUserStorageQuotaMB
+	}
 	if !hasMinimumPasswordLength(req.Password) {
 		badRequest(w, errors.New("password must be at least 6 characters"))
 		return
@@ -159,11 +168,22 @@ func (a *App) handleCreateUser(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	defer tx.Rollback()
-	if _, err = tx.ExecContext(r.Context(), `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,mailbox_limit_override,created_at,updated_at)
-		VALUES(?,?,?,?,?,?,?,?,?,?)`, id, primaryEmail, primaryEmail, displayName, role, string(passwordHash), boolInt(req.Disabled), nullableInt(mailboxLimitOverride), now, now); err != nil {
+	if _, err = tx.ExecContext(r.Context(), `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,mailbox_limit_override,storage_quota_mb,created_at,updated_at)
+		VALUES(?,?,?,?,?,?,?,?,?,?,?)`, id, primaryEmail, primaryEmail, displayName, role, string(passwordHash), boolInt(req.Disabled), nullableInt(mailboxLimitOverride), storageQuotaMB, now, now); err != nil {
 		badRequest(w, err)
 		return
 	}
+	localPart, domainName, _ := strings.Cut(primaryEmail, "@")
+	var primaryDomainID string
+	if err := tx.QueryRowContext(r.Context(), `SELECT id FROM domains WHERE lower(name)=lower(?)`, domainName).Scan(&primaryDomainID); err == nil {
+		if _, err := a.createMailboxWithPasswordHashTx(r.Context(), tx, id, primaryDomainID, localPart, displayName, string(passwordHash), storageQuotaMB, "active"); err != nil {
+			badRequest(w, err)
+			return
+		}
+	} else if !errors.Is(err, sql.ErrNoRows) {
+		respondError(w, http.StatusInternalServerError, "failed to load account domain")
+		return
+	}
 	permissionGroupIDs := req.PermissionGroupIDs
 	if role == "admin" {
 		permissionGroupIDs = nil
@@ -194,6 +214,7 @@ func (a *App) handleUpdateUser(w http.ResponseWriter, r *http.Request) {
 		Role                 string    `json:"role"`
 		Disabled             *bool     `json:"disabled"`
 		MailboxLimitOverride *int      `json:"mailboxLimitOverride"`
+		StorageQuotaMB       *int      `json:"storageQuotaMb"`
 		PermissionGroupIDs   *[]string `json:"permissionGroupIds"`
 	}
 	if err := decodeJSON(r, &req); err != nil {
@@ -267,6 +288,18 @@ func (a *App) handleUpdateUser(w http.ResponseWriter, r *http.Request) {
 	if role == "admin" {
 		mailboxLimitOverride = nil
 	}
+	var storageQuotaMB int
+	if err := a.db.QueryRowContext(r.Context(), `SELECT storage_quota_mb FROM users WHERE id=?`, id).Scan(&storageQuotaMB); err != nil {
+		respondError(w, http.StatusInternalServerError, "failed to load storage quota")
+		return
+	}
+	if req.StorageQuotaMB != nil {
+		storageQuotaMB = *req.StorageQuotaMB
+	}
+	if storageQuotaMB < 100 {
+		badRequest(w, errors.New("共享存储容量不能小于 100 MB"))
+		return
+	}
 	if err := a.ensureAdminRemains(r.Context(), id, role, disabled); err != nil {
 		badRequest(w, err)
 		return
@@ -311,8 +344,8 @@ func (a *App) handleUpdateUser(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	defer tx.Rollback()
-	if _, err := tx.ExecContext(r.Context(), `UPDATE users SET login_name=?, email=?, display_name=?, role=?, disabled=?, mailbox_limit_override=?, updated_at=? WHERE id=?`,
-		loginName, primaryEmail, displayName, role, boolInt(disabled), nullableInt(mailboxLimitOverride), a.now().UTC().Format(time.RFC3339Nano), id); err != nil {
+	if _, err := tx.ExecContext(r.Context(), `UPDATE users SET login_name=?, email=?, display_name=?, role=?, disabled=?, mailbox_limit_override=?, storage_quota_mb=?, updated_at=? WHERE id=?`,
+		loginName, primaryEmail, displayName, role, boolInt(disabled), nullableInt(mailboxLimitOverride), storageQuotaMB, a.now().UTC().Format(time.RFC3339Nano), id); err != nil {
 		if strings.Contains(strings.ToLower(err.Error()), "unique") {
 			badRequest(w, errors.New("主登录邮箱已被使用"))
 			return
@@ -409,11 +442,8 @@ func (a *App) handleDeleteUser(w http.ResponseWriter, r *http.Request) {
 	if target, err := a.userByID(r.Context(), id); err != nil {
 		respondError(w, http.StatusNotFound, "user not found")
 		return
-	} else if a.isDefaultAdminUser(target) {
-		badRequest(w, errors.New("default administrator cannot be deleted"))
-		return
-	} else if target.Role == "admin" && (current == nil || current.Role != "admin") {
-		respondError(w, http.StatusForbidden, "only administrators can delete administrator users")
+	} else if target.Role == "admin" {
+		badRequest(w, errors.New("administrator accounts cannot be deleted"))
 		return
 	}
 	if err := a.ensureAdminRemains(r.Context(), id, "user", true); err != nil {
@@ -553,6 +583,7 @@ func (a *App) handleListMailboxes(w http.ResponseWriter, r *http.Request) {
 		m.CreatedAt = parseTime(created)
 		items = append(items, m)
 	}
+	markPrimaryMailboxes(items)
 	respondJSON(w, http.StatusOK, map[string]any{"items": items})
 }
 
@@ -563,7 +594,6 @@ func (a *App) handleCreateMailbox(w http.ResponseWriter, r *http.Request) {
 		DisplayName    string `json:"displayName"`
 		Password       string `json:"password"`
 		QuotaMB        int    `json:"quotaMb"`
-		Role           string `json:"role"`
 		OwnerLoginName string `json:"ownerLoginName"`
 		OwnerEmail     string `json:"ownerEmail"`
 		UserID         string `json:"userId"`
@@ -580,20 +610,9 @@ func (a *App) handleCreateMailbox(w http.ResponseWriter, r *http.Request) {
 		badRequest(w, err)
 		return
 	}
-	if !hasMinimumPasswordLength(req.Password) {
-		badRequest(w, errors.New("password must be at least 6 characters"))
-		return
-	}
-	role := req.Role
-	if role == "" {
-		role = "user"
-	}
-	if role != "user" && role != "admin" {
-		badRequest(w, errors.New("invalid role"))
-		return
-	}
-	if role == "admin" {
-		respondError(w, http.StatusForbidden, "管理员只能由安装流程创建")
+	userID := strings.TrimSpace(req.UserID)
+	if req.QuotaMB < 0 {
+		badRequest(w, errors.New("quotaMb must be zero or greater"))
 		return
 	}
 
@@ -611,15 +630,14 @@ func (a *App) handleCreateMailbox(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	defer tx.Rollback()
-	now := a.now().UTC().Format(time.RFC3339Nano)
-	userID := strings.TrimSpace(req.UserID)
 	displayName := req.DisplayName
 	if displayName == "" {
 		displayName = address
 	}
+	var disabled, ownerStorageQuotaMB int
+	var passwordHash, ownerRole string
 	if userID != "" {
-		var disabled int
-		if err := tx.QueryRowContext(r.Context(), `SELECT disabled FROM users WHERE id=?`, userID).Scan(&disabled); err != nil {
+		if err := tx.QueryRowContext(r.Context(), `SELECT disabled,password_hash,role,storage_quota_mb FROM users WHERE id=?`, userID).Scan(&disabled, &passwordHash, &ownerRole, &ownerStorageQuotaMB); err != nil {
 			if errors.Is(err, sql.ErrNoRows) {
 				respondError(w, http.StatusNotFound, "owner user not found")
 			} else {
@@ -627,11 +645,11 @@ func (a *App) handleCreateMailbox(w http.ResponseWriter, r *http.Request) {
 			}
 			return
 		}
-		if intBool(disabled) {
-			badRequest(w, errors.New("owner user is disabled"))
+	} else {
+		if !hasMinimumPasswordLength(req.Password) {
+			badRequest(w, errors.New("password must be at least 6 characters"))
 			return
 		}
-	} else {
 		ownerEmailInput := req.OwnerEmail
 		if strings.TrimSpace(ownerEmailInput) == "" && strings.Contains(strings.TrimSpace(req.OwnerLoginName), "@") {
 			ownerEmailInput = req.OwnerLoginName
@@ -641,21 +659,20 @@ func (a *App) handleCreateMailbox(w http.ResponseWriter, r *http.Request) {
 			badRequest(w, err)
 			return
 		}
-		err = tx.QueryRowContext(r.Context(), `SELECT id FROM users WHERE email=? AND disabled=0`, ownerEmail).Scan(&userID)
+		err = tx.QueryRowContext(r.Context(), `SELECT id,disabled,password_hash,role,storage_quota_mb FROM users WHERE email=?`, ownerEmail).Scan(&userID, &disabled, &passwordHash, &ownerRole, &ownerStorageQuotaMB)
 		if errors.Is(err, sql.ErrNoRows) {
-			passwordHash, err := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
-			if err != nil {
+			hash, hashErr := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
+			if hashErr != nil {
 				respondError(w, http.StatusInternalServerError, "failed to hash password")
 				return
 			}
 			userID = newID("usr")
-			ownerDisplayName := displayName
-			if !strings.EqualFold(ownerEmail, address) {
-				ownerDisplayName = ownerEmail
-			}
-			_, err = tx.ExecContext(r.Context(), `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,created_at,updated_at)
-				VALUES(?,?,?,?,?,?,?,?,?)`, userID, ownerEmail, ownerEmail, ownerDisplayName, role, string(passwordHash), 0, now, now)
-			if err != nil {
+			passwordHash = string(hash)
+			ownerRole = "user"
+			ownerStorageQuotaMB = defaultUserStorageQuotaMB
+			now := a.now().UTC().Format(time.RFC3339Nano)
+			if _, err = tx.ExecContext(r.Context(), `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,storage_quota_mb,created_at,updated_at)
+				VALUES(?,?,?,?,?,?,?,?,?,?)`, userID, ownerEmail, ownerEmail, displayName, ownerRole, passwordHash, 0, ownerStorageQuotaMB, now, now); err != nil {
 				badRequest(w, err)
 				return
 			}
@@ -664,16 +681,26 @@ func (a *App) handleCreateMailbox(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 	}
-	if err := tx.Commit(); err != nil {
-		respondError(w, http.StatusInternalServerError, "failed to prepare owner user")
+	if intBool(disabled) {
+		badRequest(w, errors.New("owner user is disabled"))
 		return
 	}
-
-	mailboxID, err := a.createMailbox(r.Context(), userID, req.DomainID, local, displayName, req.Password, req.QuotaMB, "active")
+	quotaMB := req.QuotaMB
+	if quotaMB == 0 {
+		quotaMB = ownerStorageQuotaMB
+	}
+	if ownerRole == "admin" {
+		quotaMB = 0
+	}
+	mailboxID, err := a.createMailboxWithPasswordHashTx(r.Context(), tx, userID, req.DomainID, local, displayName, passwordHash, quotaMB, "active")
 	if err != nil {
 		badRequest(w, err)
 		return
 	}
+	if err := tx.Commit(); err != nil {
+		respondError(w, http.StatusInternalServerError, "failed to create mailbox")
+		return
+	}
 	m, err := a.mailboxByID(r.Context(), mailboxID)
 	if err != nil {
 		respondError(w, http.StatusInternalServerError, "failed to load mailbox")
@@ -699,8 +726,9 @@ func (a *App) handleUpdateMailbox(w http.ResponseWriter, r *http.Request) {
 		badRequest(w, errors.New("displayName is required"))
 		return
 	}
-	if req.QuotaMB <= 0 {
-		req.QuotaMB = 1024
+	if req.QuotaMB < 0 {
+		badRequest(w, errors.New("quotaMb must be zero or greater"))
+		return
 	}
 	status := strings.TrimSpace(req.Status)
 	if status == "" {
@@ -710,13 +738,27 @@ func (a *App) handleUpdateMailbox(w http.ResponseWriter, r *http.Request) {
 		badRequest(w, errors.New("invalid status"))
 		return
 	}
+	existingMailbox, err := a.mailboxByID(r.Context(), id)
+	if err != nil {
+		respondError(w, http.StatusNotFound, "mailbox not found")
+		return
+	}
+	if existingMailbox.Primary && status != existingMailbox.Status {
+		badRequest(w, errors.New("用户默认邮箱状态由所属账号管理，不能单独修改"))
+		return
+	}
 	userID := strings.TrimSpace(req.UserID)
 	if userID == "" {
 		badRequest(w, errors.New("userId is required"))
 		return
 	}
+	if existingMailbox.Primary && userID != existingMailbox.UserID {
+		badRequest(w, errors.New("用户默认邮箱归属由所属账号管理，不能单独修改"))
+		return
+	}
 	var disabled int
-	if err := a.db.QueryRowContext(r.Context(), `SELECT disabled FROM users WHERE id=?`, userID).Scan(&disabled); err != nil {
+	var ownerRole, ownerPasswordHash string
+	if err := a.db.QueryRowContext(r.Context(), `SELECT disabled,role,password_hash FROM users WHERE id=?`, userID).Scan(&disabled, &ownerRole, &ownerPasswordHash); err != nil {
 		if errors.Is(err, sql.ErrNoRows) {
 			respondError(w, http.StatusNotFound, "owner user not found")
 		} else {
@@ -728,8 +770,11 @@ func (a *App) handleUpdateMailbox(w http.ResponseWriter, r *http.Request) {
 		badRequest(w, errors.New("owner user is disabled"))
 		return
 	}
-	res, err := a.db.ExecContext(r.Context(), `UPDATE mailboxes SET user_id=?,display_name=?,quota_mb=?,status=?,updated_at=? WHERE id=?`,
-		userID, displayName, req.QuotaMB, status, a.now().UTC().Format(time.RFC3339Nano), id)
+	if ownerRole == "admin" {
+		req.QuotaMB = 0
+	}
+	res, err := a.db.ExecContext(r.Context(), `UPDATE mailboxes SET user_id=?,display_name=?,password_hash=?,quota_mb=?,status=?,updated_at=? WHERE id=?`,
+		userID, displayName, ownerPasswordHash, req.QuotaMB, status, a.now().UTC().Format(time.RFC3339Nano), id)
 	if err != nil {
 		respondError(w, http.StatusInternalServerError, "failed to update mailbox")
 		return
@@ -749,6 +794,14 @@ func (a *App) handleUpdateMailbox(w http.ResponseWriter, r *http.Request) {
 
 func (a *App) handleDeleteMailbox(w http.ResponseWriter, r *http.Request) {
 	id := chi.URLParam(r, "id")
+	if err := a.ensureMailboxDeletable(r.Context(), id); err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			respondError(w, http.StatusNotFound, "邮箱不存在或已被删除")
+		} else {
+			badRequest(w, err)
+		}
+		return
+	}
 	rows, err := a.db.QueryContext(r.Context(), `SELECT id FROM messages WHERE mailbox_id=?`, id)
 	if err != nil {
 		respondError(w, http.StatusInternalServerError, "加载邮箱邮件失败")
@@ -1118,15 +1171,15 @@ func (a *App) domainByID(ctx context.Context, id string) (*Domain, error) {
 }
 
 func (a *App) adminUserByID(ctx context.Context, id string) (*AdminUser, error) {
-	row := a.db.QueryRowContext(ctx, `SELECT u.id,u.login_name,u.email,u.display_name,u.role,u.disabled,u.two_factor_enabled,u.mailbox_limit_override,u.created_at,COUNT(mb.id),COALESCE(GROUP_CONCAT(mb.address), '')
+	row := a.db.QueryRowContext(ctx, `SELECT u.id,u.login_name,u.email,u.display_name,u.role,u.disabled,u.two_factor_enabled,u.mailbox_limit_override,u.storage_quota_mb,u.created_at,COUNT(mb.id),COALESCE(GROUP_CONCAT(mb.address), '')
 		FROM users u LEFT JOIN mailboxes mb ON mb.user_id=u.id
 		WHERE u.id=?
-		GROUP BY u.id,u.login_name,u.email,u.display_name,u.role,u.disabled,u.two_factor_enabled,u.mailbox_limit_override,u.created_at`, id)
+		GROUP BY u.id,u.login_name,u.email,u.display_name,u.role,u.disabled,u.two_factor_enabled,u.mailbox_limit_override,u.storage_quota_mb,u.created_at`, id)
 	var item AdminUser
 	var disabled, twoFactorEnabled int
 	var mailboxLimitOverride sql.NullInt64
 	var created, mailboxCSV string
-	if err := row.Scan(&item.ID, &item.LoginName, &item.Email, &item.DisplayName, &item.Role, &disabled, &twoFactorEnabled, &mailboxLimitOverride, &created, &item.MailboxCount, &mailboxCSV); err != nil {
+	if err := row.Scan(&item.ID, &item.LoginName, &item.Email, &item.DisplayName, &item.Role, &disabled, &twoFactorEnabled, &mailboxLimitOverride, &item.StorageQuotaMB, &created, &item.MailboxCount, &mailboxCSV); err != nil {
 		return nil, err
 	}
 	item.Disabled = intBool(disabled)
@@ -1191,9 +1244,48 @@ func (a *App) mailboxByID(ctx context.Context, id string) (*Mailbox, error) {
 		return nil, err
 	}
 	m.CreatedAt = parseTime(created)
+	if err := a.markMailboxPrimary(ctx, &m); err != nil {
+		return nil, err
+	}
 	return &m, nil
 }
 
+func markPrimaryMailboxes(items []Mailbox) {
+	primaryByUser := make(map[string]int)
+	for i := range items {
+		candidate, ok := primaryByUser[items[i].UserID]
+		if !ok || strings.EqualFold(items[i].Address, items[i].UserEmail) || (!strings.EqualFold(items[candidate].Address, items[candidate].UserEmail) && (items[i].CreatedAt.Before(items[candidate].CreatedAt) || (items[i].CreatedAt.Equal(items[candidate].CreatedAt) && items[i].ID < items[candidate].ID))) {
+			primaryByUser[items[i].UserID] = i
+		}
+	}
+	for _, index := range primaryByUser {
+		items[index].Primary = true
+	}
+}
+
+func (a *App) markMailboxPrimary(ctx context.Context, mailbox *Mailbox) error {
+	var primaryID string
+	err := a.db.QueryRowContext(ctx, `SELECT mb.id FROM mailboxes mb JOIN users u ON u.id=mb.user_id
+		WHERE mb.user_id=?
+		ORDER BY CASE WHEN lower(mb.address)=lower(u.email) THEN 0 ELSE 1 END, mb.created_at, mb.id LIMIT 1`, mailbox.UserID).Scan(&primaryID)
+	if err != nil {
+		return err
+	}
+	mailbox.Primary = mailbox.ID == primaryID
+	return nil
+}
+
+func (a *App) ensureMailboxDeletable(ctx context.Context, id string) error {
+	mailbox, err := a.mailboxByID(ctx, id)
+	if err != nil {
+		return err
+	}
+	if mailbox.Primary {
+		return errors.New("用户默认邮箱不能删除")
+	}
+	return nil
+}
+
 func (a *App) mailboxForUser(ctx context.Context, userID string) (*Mailbox, error) {
 	row := a.db.QueryRowContext(ctx, `SELECT id,user_id,domain_id,local_part,address,display_name,quota_mb,status,created_at FROM mailboxes WHERE user_id=? AND status='active' ORDER BY created_at LIMIT 1`, userID)
 	var m Mailbox

apps/api/internal/app/app.go

@@ -40,6 +40,12 @@ type App struct {
 	telegramDeliveryMu sync.Mutex
 }
 
+const (
+	defaultUserStorageQuotaMB  = 100
+	defaultAdminStorageQuotaMB = 1024
+	minimumStorageQuotaMB      = 100
+)
+
 func (a *App) config() Config {
 	a.cfgMu.RLock()
 	defer a.cfgMu.RUnlock()
@@ -97,6 +103,10 @@ func New(cfg Config, logger *slog.Logger) (*App, error) {
 		db.Close()
 		return nil, err
 	}
+	if err := a.normalizeAdministratorMailboxQuotas(context.Background()); err != nil {
+		db.Close()
+		return nil, err
+	}
 	if err := a.initializeTelegramNotificationDefaults(context.Background()); err != nil {
 		db.Close()
 		return nil, err
@@ -168,6 +178,7 @@ func (a *App) migrate(ctx context.Context) error {
 			two_factor_secret TEXT NOT NULL DEFAULT '',
 			two_factor_enabled INTEGER NOT NULL DEFAULT 0,
 			mailbox_limit_override INTEGER,
+			storage_quota_mb INTEGER NOT NULL DEFAULT 100,
 			disabled INTEGER NOT NULL DEFAULT 0,
 			created_at TEXT NOT NULL,
 			updated_at TEXT NOT NULL
@@ -673,6 +684,9 @@ func (a *App) migrate(ctx context.Context) error {
 	if err := a.migrateUserMailboxLimitOverride(ctx); err != nil {
 		return err
 	}
+	if err := a.migrateUserStorageQuota(ctx); err != nil {
+		return err
+	}
 	if err := a.migrateMailRulesBuilder(ctx); err != nil {
 		return err
 	}
@@ -1335,6 +1349,39 @@ func (a *App) migrateUserMailboxLimitOverride(ctx context.Context) error {
 	return err
 }
 
+func (a *App) migrateUserStorageQuota(ctx context.Context) error {
+	rows, err := a.db.QueryContext(ctx, `PRAGMA table_info(users)`)
+	if err != nil {
+		return err
+	}
+	hasColumn := false
+	for rows.Next() {
+		var cid int
+		var name, typ string
+		var notnull int
+		var dflt any
+		var pk int
+		if err := rows.Scan(&cid, &name, &typ, &notnull, &dflt, &pk); err != nil {
+			rows.Close()
+			return err
+		}
+		if name == "storage_quota_mb" {
+			hasColumn = true
+		}
+	}
+	if err := rows.Close(); err != nil {
+		return err
+	}
+	if hasColumn {
+		return nil
+	}
+	if _, err := a.db.ExecContext(ctx, `ALTER TABLE users ADD COLUMN storage_quota_mb INTEGER NOT NULL DEFAULT 100`); err != nil {
+		return err
+	}
+	_, err = a.db.ExecContext(ctx, `UPDATE users SET storage_quota_mb=? WHERE role='admin'`, defaultAdminStorageQuotaMB)
+	return err
+}
+
 func (a *App) migrateMessagesForUnregistered(ctx context.Context) error {
 	rows, err := a.db.QueryContext(ctx, `PRAGMA table_info(messages)`)
 	if err != nil {
@@ -1513,8 +1560,8 @@ func (a *App) seed(ctx context.Context) error {
 	}
 	now := a.now().UTC().Format(time.RFC3339Nano)
 	userID := newID("usr")
-	if _, err := a.db.ExecContext(ctx, `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,created_at,updated_at)
-		VALUES(?,?,?,?,?,?,?,?,?)`, userID, adminEmail, adminEmail, "NewSzxcn Admin", "admin", string(passwordHash), 0, now, now); err != nil {
+	if _, err := a.db.ExecContext(ctx, `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,storage_quota_mb,created_at,updated_at)
+		VALUES(?,?,?,?,?,?,?,?,?,?)`, userID, adminEmail, adminEmail, "NewSzxcn Admin", "admin", string(passwordHash), 0, defaultAdminStorageQuotaMB, now, now); err != nil {
 		return err
 	}
 	a.log.Warn("created default administrator; change LANQIN_ADMIN_PASSWORD in production", "email", adminEmail)
@@ -1535,7 +1582,7 @@ func (a *App) seed(ctx context.Context) error {
 	}
 
 	// Create mailbox for admin
-	mailboxID, err := a.createMailboxWithPasswordHash(ctx, userID, domainID, localPart, adminEmail, string(passwordHash), 1024, "active")
+	mailboxID, err := a.createMailboxWithPasswordHash(ctx, userID, domainID, localPart, adminEmail, string(passwordHash), 0, "active")
 	if err != nil {
 		return err
 	}
@@ -1656,7 +1703,7 @@ func (a *App) migrateConfiguredAdministratorIdentity(ctx context.Context) error
 		if !errors.Is(err, sql.ErrNoRows) {
 			return err
 		}
-		mailboxID, err = a.createMailboxWithPasswordHashTx(ctx, tx, keeper.ID, domainID, localPart, adminEmail, keeper.PasswordHash, 1024, "active")
+		mailboxID, err = a.createMailboxWithPasswordHashTx(ctx, tx, keeper.ID, domainID, localPart, adminEmail, keeper.PasswordHash, 0, "active")
 		if err != nil {
 			return err
 		}
@@ -1871,8 +1918,15 @@ func (a *App) createMailboxWithPasswordHashTx(ctx context.Context, tx *sql.Tx, u
 	if localPart == "" {
 		return "", errors.New("invalid local part")
 	}
-	if quotaMB <= 0 {
-		quotaMB = 1024
+	if quotaMB < 0 {
+		return "", errors.New("quotaMb must be zero or greater")
+	}
+	var ownerRole string
+	if err := tx.QueryRowContext(ctx, `SELECT role FROM users WHERE id=?`, userID).Scan(&ownerRole); err != nil {
+		return "", err
+	}
+	if ownerRole == "admin" {
+		quotaMB = 0
 	}
 	if status == "" {
 		status = "active"
@@ -1905,6 +1959,17 @@ func (a *App) createMailboxWithPasswordHashTx(ctx context.Context, tx *sql.Tx, u
 	return id, nil
 }
 
+func (a *App) normalizeAdministratorMailboxQuotas(ctx context.Context) error {
+	now := a.now().UTC().Format(time.RFC3339Nano)
+	if _, err := a.db.ExecContext(ctx, `UPDATE users SET storage_quota_mb=CASE WHEN role='admin' THEN ? ELSE ? END, updated_at=? WHERE storage_quota_mb<?`, defaultAdminStorageQuotaMB, defaultUserStorageQuotaMB, now, minimumStorageQuotaMB); err != nil {
+		return err
+	}
+	_, err := a.db.ExecContext(ctx, `UPDATE mailboxes
+		SET quota_mb=0, updated_at=?
+		WHERE quota_mb<>0 AND user_id IN (SELECT id FROM users WHERE role='admin')`, now)
+	return err
+}
+
 func (a *App) seedWelcomeMessage(ctx context.Context, mailboxID string) error {
 	cfg := a.config()
 	folderID, err := a.ensureFolder(ctx, mailboxID, "Inbox")

apps/api/internal/app/app_test.go

@@ -363,6 +363,147 @@ func createTestMailbox(t *testing.T, admin *testClient, domainID, localPart, dis
 	return mailbox
 }
 
+func TestAdminMailboxCreationUsesOwnerPasswordAndQuota(t *testing.T) {
+	a := newTestApp(t)
+	ts := httptest.NewServer(a.Router())
+	defer ts.Close()
+	admin := &testClient{t: t, server: ts}
+	var login map[string]any
+	if code := admin.do("POST", "/api/auth/login", map[string]string{"email": "admin@lanqin.local", "password": "ChangeMe123!"}, &login); code != http.StatusOK {
+		t.Fatalf("login code=%d body=%v", code, login)
+	}
+	adminUser, adminMailbox := defaultAdminUserAndMailbox(t, a)
+	adminDetails, err := a.adminUserByID(context.Background(), adminUser.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if adminDetails.StorageQuotaMB != defaultAdminStorageQuotaMB {
+		t.Fatalf("administrator storage quota=%d, want %d", adminDetails.StorageQuotaMB, defaultAdminStorageQuotaMB)
+	}
+	domainID := mustDefaultDomainID(t, a)
+
+	var secondary Mailbox
+	if code := admin.do("POST", "/api/admin/mailboxes", map[string]any{
+		"domainId":  domainID,
+		"localPart": "admin-secondary",
+		"userId":    adminUser.ID,
+	}, &secondary); code != http.StatusCreated {
+		t.Fatalf("create admin secondary mailbox code=%d", code)
+	}
+	if secondary.QuotaMB != 0 {
+		t.Fatalf("admin secondary quota=%d, want unlimited", secondary.QuotaMB)
+	}
+
+	var primaryHash, secondaryHash string
+	if err := a.db.QueryRow(`SELECT password_hash FROM mailboxes WHERE id=?`, adminMailbox.ID).Scan(&primaryHash); err != nil {
+		t.Fatal(err)
+	}
+	if err := a.db.QueryRow(`SELECT password_hash FROM mailboxes WHERE id=?`, secondary.ID).Scan(&secondaryHash); err != nil {
+		t.Fatal(err)
+	}
+	if primaryHash != secondaryHash {
+		t.Fatal("admin secondary mailbox did not inherit the owner password")
+	}
+
+	var regular AdminUser
+	if code := admin.do("POST", "/api/admin/users", map[string]any{
+		"email":       "owner@lanqin.local",
+		"displayName": "Owner",
+		"password":    "OwnerPassword123!",
+		"role":        "user",
+	}, &regular); code != http.StatusCreated {
+		t.Fatalf("create regular owner code=%d", code)
+	}
+	if regular.MailboxCount != 1 {
+		t.Fatalf("new account mailbox count=%d, want one protected primary mailbox", regular.MailboxCount)
+	}
+	if regular.StorageQuotaMB != defaultUserStorageQuotaMB {
+		t.Fatalf("regular account storage quota=%d, want %d", regular.StorageQuotaMB, defaultUserStorageQuotaMB)
+	}
+	if _, err := a.mailboxByAddress(context.Background(), regular.Email); err != nil {
+		t.Fatalf("new account primary mailbox missing: %v", err)
+	}
+	var primaryStatusErr map[string]any
+	primaryMailbox, err := a.mailboxByAddress(context.Background(), regular.Email)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if code := admin.do("POST", "/api/admin/mailboxes/"+primaryMailbox.ID, map[string]any{
+		"userId": regular.ID, "displayName": primaryMailbox.DisplayName, "quotaMb": primaryMailbox.QuotaMB, "status": "disabled",
+	}, &primaryStatusErr); code != http.StatusBadRequest {
+		t.Fatalf("primary mailbox status update code=%d body=%v", code, primaryStatusErr)
+	}
+	var regularMailbox Mailbox
+	if code := admin.do("POST", "/api/admin/mailboxes", map[string]any{
+		"domainId":  domainID,
+		"localPart": "owner-secondary",
+		"userId":    regular.ID,
+	}, &regularMailbox); code != http.StatusCreated {
+		t.Fatalf("create regular secondary mailbox code=%d", code)
+	}
+	if regularMailbox.QuotaMB != defaultUserStorageQuotaMB {
+		t.Fatalf("regular secondary quota=%d, want %d", regularMailbox.QuotaMB, defaultUserStorageQuotaMB)
+	}
+	var userHash, mailboxHash string
+	if err := a.db.QueryRow(`SELECT password_hash FROM users WHERE id=?`, regular.ID).Scan(&userHash); err != nil {
+		t.Fatal(err)
+	}
+	if err := a.db.QueryRow(`SELECT password_hash FROM mailboxes WHERE id=?`, regularMailbox.ID).Scan(&mailboxHash); err != nil {
+		t.Fatal(err)
+	}
+	if userHash != mailboxHash {
+		t.Fatal("regular secondary mailbox did not inherit the owner password")
+	}
+}
+
+func TestAdministratorAccountAndPrimaryMailboxesCannotBeDeleted(t *testing.T) {
+	a := newTestApp(t)
+	ts := httptest.NewServer(a.Router())
+	defer ts.Close()
+	admin := &testClient{t: t, server: ts}
+	var login map[string]any
+	if code := admin.do("POST", "/api/auth/login", map[string]string{"email": "admin@lanqin.local", "password": "ChangeMe123!"}, &login); code != http.StatusOK {
+		t.Fatalf("login code=%d body=%v", code, login)
+	}
+	adminUser, adminMailbox := defaultAdminUserAndMailbox(t, a)
+	var errBody map[string]any
+	if code := admin.do("DELETE", "/api/admin/users/"+adminUser.ID, nil, &errBody); code != http.StatusBadRequest {
+		t.Fatalf("administrator account delete code=%d body=%v", code, errBody)
+	}
+	if code := admin.do("DELETE", "/api/admin/mailboxes/"+adminMailbox.ID, nil, &errBody); code != http.StatusBadRequest {
+		t.Fatalf("administrator primary mailbox delete code=%d body=%v", code, errBody)
+	}
+	if code := admin.do("POST", "/api/admin/users/"+adminUser.ID, map[string]any{
+		"email": adminUser.Email, "displayName": adminUser.DisplayName, "role": "admin", "disabled": false, "storageQuotaMb": 99,
+	}, &errBody); code != http.StatusBadRequest {
+		t.Fatalf("storage quota below 100 MB code=%d body=%v", code, errBody)
+	}
+	var updatedAdmin AdminUser
+	if code := admin.do("POST", "/api/admin/users/"+adminUser.ID, map[string]any{
+		"email": adminUser.Email, "displayName": adminUser.DisplayName, "role": "admin", "disabled": false, "storageQuotaMb": 100,
+	}, &updatedAdmin); code != http.StatusOK || updatedAdmin.StorageQuotaMB != 100 {
+		t.Fatalf("administrator storage quota code=%d user=%+v", code, updatedAdmin)
+	}
+
+	var regular AdminUser
+	if code := admin.do("POST", "/api/admin/users", map[string]any{
+		"email": "protected-primary@lanqin.local", "displayName": "Protected Primary", "role": "user", "password": "Password123!",
+	}, &regular); code != http.StatusCreated {
+		t.Fatalf("create regular user code=%d user=%+v", code, regular)
+	}
+	primary, err := a.mailboxByAddress(context.Background(), regular.Email)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if code := admin.do("DELETE", "/api/admin/mailboxes/"+primary.ID, nil, &errBody); code != http.StatusBadRequest {
+		t.Fatalf("regular primary mailbox delete code=%d body=%v", code, errBody)
+	}
+	secondary := createTestMailbox(t, admin, primary.DomainID, "deletable-secondary", "Secondary", "", map[string]any{"userId": regular.ID})
+	if code := admin.do("DELETE", "/api/admin/mailboxes/"+secondary.ID, nil, &errBody); code != http.StatusOK {
+		t.Fatalf("secondary mailbox delete code=%d body=%v", code, errBody)
+	}
+}
+
 func createTestAPIToken(t *testing.T, client *testClient, name string) string {
 	return createTestAPITokenWithScopes(t, client, name, nil)
 }
@@ -1574,6 +1715,13 @@ func TestOpenRegistrationAtomicallyCreatesLoginUserAndMailbox(t *testing.T) {
 	if code := client.do("POST", "/api/auth/register", registration, &registered); code != http.StatusCreated || registered.User.Email != "newuser@lanqin.local" || registered.User.Role != "user" {
 		t.Fatalf("register code=%d user=%+v", code, registered.User)
 	}
+	var storageQuotaMB int
+	if err := a.db.QueryRow(`SELECT storage_quota_mb FROM users WHERE id=?`, registered.User.ID).Scan(&storageQuotaMB); err != nil {
+		t.Fatal(err)
+	}
+	if storageQuotaMB != defaultUserStorageQuotaMB {
+		t.Fatalf("registered account storage quota=%d, want %d", storageQuotaMB, defaultUserStorageQuotaMB)
+	}
 	var me struct {
 		User User `json:"user"`
 	}
@@ -3177,20 +3325,45 @@ func TestOpenAPIDomainAndMailboxCRUD(t *testing.T) {
 	if code := openAdmin.do("POST", "/api/open/domains/"+domain.ID, map[string]string{"status": "active"}, &domain); code != http.StatusOK {
 		t.Fatalf("reactivate open api domain code=%d domain=%+v", code, domain)
 	}
+	var owner AdminUser
+	if code := admin.do("POST", "/api/admin/users", map[string]any{
+		"email": "open-api-owner@lanqin.local", "displayName": "Open API Owner", "role": "user", "password": "Password123!",
+	}, &owner); code != http.StatusCreated {
+		t.Fatalf("create open api mailbox owner code=%d owner=%+v", code, owner)
+	}
 
 	var mailbox Mailbox
 	if code := openAdmin.do("POST", "/api/open/mailboxes", map[string]any{
 		"domainId":    domain.ID,
 		"localPart":   "api-user",
 		"displayName": "API User",
-		"password":    "Password123!",
+		"password":    "DifferentPassword123!",
 		"quotaMb":     256,
+		"userId":      owner.ID,
 	}, &mailbox); code != http.StatusCreated {
 		t.Fatalf("create open api mailbox code=%d mailbox=%+v", code, mailbox)
 	}
+	ownerPrimary, err := a.mailboxByAddress(context.Background(), owner.Email)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var protectedMailboxErr map[string]any
+	if code := openAdmin.do("POST", "/api/open/mailboxes/"+ownerPrimary.ID, map[string]any{"status": "disabled"}, &protectedMailboxErr); code != http.StatusBadRequest {
+		t.Fatalf("open api primary mailbox status update code=%d body=%v", code, protectedMailboxErr)
+	}
 	if mailbox.Address != "api-user@api.example.test" || mailbox.QuotaMB != 256 {
 		t.Fatalf("mailbox=%+v", mailbox)
 	}
+	var ownerPasswordHash, mailboxPasswordHash string
+	if err := a.db.QueryRowContext(context.Background(), `SELECT password_hash FROM users WHERE id=?`, owner.ID).Scan(&ownerPasswordHash); err != nil {
+		t.Fatal(err)
+	}
+	if err := a.db.QueryRowContext(context.Background(), `SELECT password_hash FROM mailboxes WHERE id=?`, mailbox.ID).Scan(&mailboxPasswordHash); err != nil {
+		t.Fatal(err)
+	}
+	if mailboxPasswordHash != ownerPasswordHash {
+		t.Fatal("open api mailbox did not inherit the owner password")
+	}
 	var mailboxes struct {
 		Items []Mailbox `json:"items"`
 	}
@@ -3207,6 +3380,9 @@ func TestOpenAPIDomainAndMailboxCRUD(t *testing.T) {
 	if updated.DisplayName != "Renamed API User" || updated.QuotaMB != 512 || updated.Status != "disabled" {
 		t.Fatalf("updated mailbox=%+v", updated)
 	}
+	if code := openAdmin.do("POST", "/api/open/mailboxes/"+mailbox.ID, map[string]any{"status": "active"}, &updated); code != http.StatusOK || updated.QuotaMB != 512 {
+		t.Fatalf("open api mailbox omitted quota should preserve 512 MB: code=%d mailbox=%+v", code, updated)
+	}
 	var ok map[string]any
 	if code := openAdmin.do("DELETE", "/api/open/mailboxes/"+mailbox.ID, nil, &ok); code != http.StatusOK {
 		t.Fatalf("delete open api mailbox code=%d body=%v", code, ok)
@@ -5195,20 +5371,24 @@ func TestFixedRolesProtectAdminRoutesAndDefaultAdmin(t *testing.T) {
 	}, &errBody); code != http.StatusForbidden {
 		t.Fatalf("system permission group update should be forbidden code=%d body=%v", code, errBody)
 	}
-	var regularUpdateErr map[string]any
+	var updatedRegular PermissionGroup
 	if code := admin.do("POST", "/api/admin/permission-groups/"+PermissionGroupRegular, map[string]any{
 		"name":        "Changed Regular",
 		"description": "Should not change",
-		"permissions": []string{PermissionAdminOverview},
-	}, &regularUpdateErr); code != http.StatusForbidden {
-		t.Fatalf("regular system permission group update should be forbidden code=%d body=%v", code, regularUpdateErr)
+		"permissions": regularUserDefaultPermissions(),
+		"limits":      defaultPermissionLimits(),
+	}, &updatedRegular); code != http.StatusOK {
+		t.Fatalf("regular system permission group update code=%d group=%+v", code, updatedRegular)
+	}
+	if updatedRegular.Name != "普通用户" || updatedRegular.Description != "仅可使用自己的邮箱功能，不包含后台权限。" {
+		t.Fatalf("regular system permission group identity changed: %+v", updatedRegular)
 	}
 	regularGroup, err := a.permissionGroupByID(context.Background(), PermissionGroupRegular)
 	if err != nil {
 		t.Fatal(err)
 	}
 	if !regularGroup.System || !userHasPermission(&User{Role: "user", Permissions: regularGroup.Permissions}, PermissionMailAccess) || userHasPermission(&User{Role: "user", Permissions: regularGroup.Permissions}, PermissionAdminOverview) {
-		t.Fatalf("regular group should stay locked with default permissions=%+v", regularGroup)
+		t.Fatalf("regular group should retain the saved default permissions=%+v", regularGroup)
 	}
 	if code := admin.do("DELETE", "/api/admin/permission-groups/"+PermissionGroupSuperAdmin, nil, &errBody); code != http.StatusForbidden {
 		t.Fatalf("system permission group delete should be forbidden code=%d body=%v", code, errBody)
@@ -6357,7 +6537,7 @@ func TestMailboxQuotaRejectsNewMessage(t *testing.T) {
 	ctx := context.Background()
 	user, mb := defaultAdminUserAndMailbox(t, a)
 	clearMailboxMessagesForTest(t, a, mb.ID)
-	if _, err := a.db.ExecContext(ctx, `UPDATE mailboxes SET quota_mb=1 WHERE id=?`, mb.ID); err != nil {
+	if _, err := a.db.ExecContext(ctx, `UPDATE users SET storage_quota_mb=1 WHERE id=?`, user.ID); err != nil {
 		t.Fatal(err)
 	}
 	_, err := a.sendMailNow(ctx, user, mb, mailComposeInput{
@@ -6433,7 +6613,11 @@ func TestMailStatsQuotaAndCleanupIsolation(t *testing.T) {
 	if code := alice.do("GET", "/api/me/stats?mailboxId="+aliceMB.ID+"&days=7", nil, &stats); code != http.StatusOK {
 		t.Fatalf("stats code=%d stats=%+v", code, stats)
 	}
-	if stats.QuotaBytes != int64(aliceMB.QuotaMB)*1024*1024 || stats.AttachmentBytes == 0 || stats.QuotaUsedPct <= 0 {
+	var aliceStorageQuotaMB int64
+	if err := a.db.QueryRowContext(ctx, `SELECT storage_quota_mb FROM users WHERE id=?`, aliceUser.ID).Scan(&aliceStorageQuotaMB); err != nil {
+		t.Fatal(err)
+	}
+	if stats.QuotaBytes != aliceStorageQuotaMB*1024*1024 || stats.AttachmentBytes == 0 || stats.QuotaUsedPct <= 0 {
 		t.Fatalf("stats quota/attachment not populated: %+v", stats)
 	}
 	if stats.TotalIncoming != 1 || stats.TotalOutgoing != 0 || stats.AverageMessageBytes <= 0 {

apps/api/internal/app/auth_handlers.go

@@ -177,8 +177,8 @@ func (a *App) handleRegister(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	defer tx.Rollback()
-	if _, err := tx.ExecContext(r.Context(), `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,created_at,updated_at)
-		VALUES(?,?,?,?,?,?,?,?,?)`, userID, email, email, displayName, "user", string(passwordHash), 0, now, now); err != nil {
+	if _, err := tx.ExecContext(r.Context(), `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,storage_quota_mb,created_at,updated_at)
+		VALUES(?,?,?,?,?,?,?,?,?,?)`, userID, email, email, displayName, "user", string(passwordHash), 0, defaultUserStorageQuotaMB, now, now); err != nil {
 		if strings.Contains(strings.ToLower(err.Error()), "unique") {
 			respondError(w, http.StatusConflict, "该邮箱已被注册")
 			return
@@ -186,7 +186,7 @@ func (a *App) handleRegister(w http.ResponseWriter, r *http.Request) {
 		respondError(w, http.StatusInternalServerError, "注册失败，请稍后重试")
 		return
 	}
-	if _, err := a.createMailboxWithPasswordHashTx(r.Context(), tx, userID, mailboxDomainID, mailboxLocalPart, displayName, string(passwordHash), 1024, "active"); err != nil {
+	if _, err := a.createMailboxWithPasswordHashTx(r.Context(), tx, userID, mailboxDomainID, mailboxLocalPart, displayName, string(passwordHash), defaultUserStorageQuotaMB, "active"); err != nil {
 		if strings.Contains(strings.ToLower(err.Error()), "unique") {
 			respondError(w, http.StatusConflict, "该邮箱已被注册")
 		} else {

apps/api/internal/app/mail_handlers.go

@@ -87,6 +87,7 @@ func (a *App) handleMyMailboxes(w http.ResponseWriter, r *http.Request) {
 		m.CreatedAt = parseTime(created)
 		items = append(items, m)
 	}
+	markPrimaryMailboxes(items)
 	respondJSON(w, http.StatusOK, map[string]any{"items": items})
 }
 
@@ -2619,14 +2620,15 @@ func (a *App) ensureMailboxQuotaAvailable(ctx context.Context, db dbExecutor, ma
 		return nil
 	}
 	var quotaMB int64
-	if err := rowDB.QueryRowContext(ctx, `SELECT quota_mb FROM mailboxes WHERE id=? AND status='active'`, mailboxID).Scan(&quotaMB); err != nil {
+	var userID string
+	if err := rowDB.QueryRowContext(ctx, `SELECT u.storage_quota_mb,mb.user_id FROM mailboxes mb JOIN users u ON u.id=mb.user_id WHERE mb.id=? AND mb.status='active'`, mailboxID).Scan(&quotaMB, &userID); err != nil {
 		return err
 	}
 	if quotaMB <= 0 {
 		return nil
 	}
 	var used int64
-	if err := rowDB.QueryRowContext(ctx, `SELECT COALESCE(SUM(size_bytes),0) FROM messages WHERE mailbox_id=?`, mailboxID).Scan(&used); err != nil {
+	if err := rowDB.QueryRowContext(ctx, `SELECT COALESCE(SUM(m.size_bytes),0) FROM messages m JOIN mailboxes mb ON mb.id=m.mailbox_id WHERE mb.user_id=?`, userID).Scan(&used); err != nil {
 		return err
 	}
 	quotaBytes := quotaMB * 1024 * 1024

apps/api/internal/app/mailbox_delete_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 )
 
-func TestAdminCanDeleteOwnLastMailboxWithoutDeletingAccount(t *testing.T) {
+func TestAdminCannotDeleteOwnPrimaryMailbox(t *testing.T) {
 	a := newTestApp(t)
 	ts := httptest.NewServer(a.Router())
 	defer ts.Close()
@@ -21,10 +21,13 @@ func TestAdminCanDeleteOwnLastMailboxWithoutDeletingAccount(t *testing.T) {
 	if code := admin.do("GET", "/api/mail/mailboxes", nil, &mailboxes); code != http.StatusOK || len(mailboxes.Items) != 1 {
 		t.Fatalf("mailboxes code=%d items=%d", code, len(mailboxes.Items))
 	}
-	if code := admin.do("DELETE", "/api/admin/mailboxes/"+mailboxes.Items[0].ID, nil, &map[string]any{}); code != http.StatusOK {
-		t.Fatalf("delete final mailbox code=%d", code)
+	if !mailboxes.Items[0].Primary {
+		t.Fatal("administrator mailbox should be marked as primary")
 	}
-	if code := admin.do("GET", "/api/mail/mailboxes", nil, &mailboxes); code != http.StatusOK || len(mailboxes.Items) != 0 {
+	if code := admin.do("DELETE", "/api/admin/mailboxes/"+mailboxes.Items[0].ID, nil, &map[string]any{}); code != http.StatusBadRequest {
+		t.Fatalf("delete primary mailbox code=%d", code)
+	}
+	if code := admin.do("GET", "/api/mail/mailboxes", nil, &mailboxes); code != http.StatusOK || len(mailboxes.Items) != 1 {
 		t.Fatalf("mailboxes after delete code=%d items=%d", code, len(mailboxes.Items))
 	}
 	var me map[string]any

apps/api/internal/app/open_api_handlers.go

@@ -200,6 +200,10 @@ func (a *App) handleOpenAPICreateMailbox(w http.ResponseWriter, r *http.Request)
 		badRequest(w, errors.New("password must be at least 6 characters"))
 		return
 	}
+	if req.QuotaMB < 0 {
+		badRequest(w, errors.New("quotaMb must be zero or greater"))
+		return
+	}
 	domain, err := a.domainByID(r.Context(), req.DomainID)
 	if err != nil {
 		respondError(w, http.StatusNotFound, "domain not found")
@@ -231,7 +235,20 @@ func (a *App) handleOpenAPICreateMailbox(w http.ResponseWriter, r *http.Request)
 		respondMailboxOwnerError(w, err)
 		return
 	}
-	mailboxID, err := a.createMailboxWithPasswordHashTx(r.Context(), tx, userID, req.DomainID, localPart, displayName, string(passwordHash), req.QuotaMB, "active")
+	var ownerPasswordHash, ownerRole string
+	var ownerStorageQuotaMB int
+	if err := tx.QueryRowContext(r.Context(), `SELECT password_hash,role,storage_quota_mb FROM users WHERE id=?`, userID).Scan(&ownerPasswordHash, &ownerRole, &ownerStorageQuotaMB); err != nil {
+		respondError(w, http.StatusInternalServerError, "failed to load owner user")
+		return
+	}
+	quotaMB := req.QuotaMB
+	if quotaMB == 0 {
+		quotaMB = ownerStorageQuotaMB
+	}
+	if ownerRole == "admin" {
+		quotaMB = 0
+	}
+	mailboxID, err := a.createMailboxWithPasswordHashTx(r.Context(), tx, userID, req.DomainID, localPart, displayName, ownerPasswordHash, quotaMB, "active")
 	if err != nil {
 		badRequest(w, err)
 		return
@@ -279,7 +296,11 @@ func (a *App) handleOpenAPIUpdateMailbox(w http.ResponseWriter, r *http.Request)
 		displayName = current.DisplayName
 	}
 	quotaMB := req.QuotaMB
-	if quotaMB <= 0 {
+	if quotaMB < 0 {
+		badRequest(w, errors.New("quotaMb must be zero or greater"))
+		return
+	}
+	if quotaMB == 0 {
 		quotaMB = current.QuotaMB
 	}
 	status := strings.TrimSpace(req.Status)
@@ -294,12 +315,28 @@ func (a *App) handleOpenAPIUpdateMailbox(w http.ResponseWriter, r *http.Request)
 	if userID == "" {
 		userID = current.UserID
 	}
+	if current.Primary && userID != current.UserID {
+		badRequest(w, errors.New("用户默认邮箱归属由所属账号管理，不能单独修改"))
+		return
+	}
+	if current.Primary && status != current.Status {
+		badRequest(w, errors.New("用户默认邮箱状态由所属账号管理，不能单独修改"))
+		return
+	}
 	if err := a.ensureActiveUserExists(r.Context(), userID); err != nil {
 		respondMailboxOwnerError(w, err)
 		return
 	}
-	res, err := a.db.ExecContext(r.Context(), `UPDATE mailboxes SET user_id=?,display_name=?,quota_mb=?,status=?,updated_at=? WHERE id=?`,
-		userID, displayName, quotaMB, status, a.now().UTC().Format(time.RFC3339Nano), id)
+	var ownerRole, ownerPasswordHash string
+	if err := a.db.QueryRowContext(r.Context(), `SELECT role,password_hash FROM users WHERE id=?`, userID).Scan(&ownerRole, &ownerPasswordHash); err != nil {
+		respondError(w, http.StatusInternalServerError, "failed to load owner user")
+		return
+	}
+	if ownerRole == "admin" {
+		quotaMB = 0
+	}
+	res, err := a.db.ExecContext(r.Context(), `UPDATE mailboxes SET user_id=?,display_name=?,password_hash=?,quota_mb=?,status=?,updated_at=? WHERE id=?`,
+		userID, displayName, ownerPasswordHash, quotaMB, status, a.now().UTC().Format(time.RFC3339Nano), id)
 	if err != nil {
 		respondError(w, http.StatusInternalServerError, "failed to update mailbox")
 		return
@@ -318,6 +355,14 @@ func (a *App) handleOpenAPIUpdateMailbox(w http.ResponseWriter, r *http.Request)
 
 func (a *App) handleOpenAPIDeleteMailbox(w http.ResponseWriter, r *http.Request) {
 	id := chi.URLParam(r, "id")
+	if err := a.ensureMailboxDeletable(r.Context(), id); err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			respondError(w, http.StatusNotFound, "邮箱不存在或已被删除")
+		} else {
+			badRequest(w, err)
+		}
+		return
+	}
 	rows, err := a.db.QueryContext(r.Context(), `SELECT id FROM messages WHERE mailbox_id=?`, id)
 	if err != nil {
 		respondError(w, http.StatusInternalServerError, "加载邮箱邮件失败")
@@ -821,8 +866,8 @@ func (a *App) resolveMailboxOwnerTx(ctx context.Context, tx *sql.Tx, userID, own
 	if displayName == "" {
 		displayName = email
 	}
-	_, err = tx.ExecContext(ctx, `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,created_at,updated_at)
-		VALUES(?,?,?,?,?,?,?,?,?)`, userID, email, email, displayName, "user", passwordHash, 0, now, now)
+	_, err = tx.ExecContext(ctx, `INSERT INTO users(id,login_name,email,display_name,role,password_hash,disabled,storage_quota_mb,created_at,updated_at)
+		VALUES(?,?,?,?,?,?,?,?,?,?)`, userID, email, email, displayName, "user", passwordHash, 0, defaultUserStorageQuotaMB, now, now)
 	return userID, err
 }
 

apps/api/internal/app/permission_group_handlers.go

@@ -142,11 +142,12 @@ func (a *App) handleCreatePermissionGroup(w http.ResponseWriter, r *http.Request
 func (a *App) handleUpdatePermissionGroup(w http.ResponseWriter, r *http.Request) {
 	id := chi.URLParam(r, "id")
 	var existingSystem int
-	if err := a.db.QueryRowContext(r.Context(), `SELECT system FROM permission_groups WHERE id=?`, id).Scan(&existingSystem); err != nil {
+	var existingName, existingDescription string
+	if err := a.db.QueryRowContext(r.Context(), `SELECT system,name,description FROM permission_groups WHERE id=?`, id).Scan(&existingSystem, &existingName, &existingDescription); err != nil {
 		respondError(w, http.StatusNotFound, "permission group not found")
 		return
 	}
-	if intBool(existingSystem) {
+	if intBool(existingSystem) && id != PermissionGroupRegular {
 		respondError(w, http.StatusForbidden, "system permission groups cannot be edited")
 		return
 	}
@@ -161,6 +162,10 @@ func (a *App) handleUpdatePermissionGroup(w http.ResponseWriter, r *http.Request
 		return
 	}
 	name := strings.TrimSpace(req.Name)
+	if id == PermissionGroupRegular {
+		name = existingName
+		req.Description = existingDescription
+	}
 	if name == "" {
 		badRequest(w, errors.New("name is required"))
 		return

apps/api/internal/app/personal_handlers.go

@@ -111,7 +111,11 @@ func (a *App) handleApplyMailbox(w http.ResponseWriter, r *http.Request) {
 		badRequest(w, errors.New("displayName must be at most 80 characters"))
 		return
 	}
-	mailboxID, err := a.createMailboxWithPasswordHash(r.Context(), user.ID, domainID, localPart, displayName, passwordHash, 1024, "active")
+	quotaMB := defaultUserStorageQuotaMB
+	if user.Role == "admin" {
+		quotaMB = 0
+	}
+	mailboxID, err := a.createMailboxWithPasswordHash(r.Context(), user.ID, domainID, localPart, displayName, passwordHash, quotaMB, "active")
 	if err != nil {
 		if strings.Contains(strings.ToLower(err.Error()), "unique") {
 			respondError(w, http.StatusConflict, "该邮箱地址已被占用")
@@ -900,26 +904,14 @@ func (a *App) handleMailStats(w http.ResponseWriter, r *http.Request) {
 		respondError(w, http.StatusInternalServerError, "failed to load send queue stats")
 		return
 	}
-	if mailboxID != "" && !isAllMailboxID(mailboxID) {
-		var quotaMB int64
-		if err := a.db.QueryRowContext(r.Context(), `SELECT quota_mb FROM mailboxes WHERE id=? AND user_id=?`, mailboxID, user.ID).Scan(&quotaMB); err != nil {
-			respondError(w, http.StatusInternalServerError, "failed to load quota")
-			return
-		}
-		stats.QuotaBytes = quotaMB * 1024 * 1024
-		if stats.QuotaBytes > 0 {
-			stats.QuotaUsedPct = float64(stats.StorageBytes) / float64(stats.QuotaBytes) * 100
-		}
-	} else {
-		var quotaMB int64
-		if err := a.db.QueryRowContext(r.Context(), `SELECT COALESCE(SUM(mb.quota_mb),0) FROM mailboxes mb WHERE `+where, args...).Scan(&quotaMB); err != nil {
-			respondError(w, http.StatusInternalServerError, "failed to load quota")
-			return
-		}
-		stats.QuotaBytes = quotaMB * 1024 * 1024
-		if stats.QuotaBytes > 0 {
-			stats.QuotaUsedPct = float64(stats.StorageBytes) / float64(stats.QuotaBytes) * 100
-		}
+	var quotaMB int64
+	if err := a.db.QueryRowContext(r.Context(), `SELECT storage_quota_mb FROM users WHERE id=?`, user.ID).Scan(&quotaMB); err != nil {
+		respondError(w, http.StatusInternalServerError, "failed to load quota")
+		return
+	}
+	stats.QuotaBytes = quotaMB * 1024 * 1024
+	if stats.QuotaBytes > 0 {
+		stats.QuotaUsedPct = float64(stats.StorageBytes) / float64(stats.QuotaBytes) * 100
 	}
 	rows, err := a.db.QueryContext(r.Context(), `SELECT f.name,f.role,COUNT(m.id),COALESCE(SUM(CASE WHEN m.is_read=0 THEN 1 ELSE 0 END),0),COALESCE(SUM(m.size_bytes),0)
 		FROM mailboxes mb JOIN folders f ON f.mailbox_id=mb.id LEFT JOIN messages m ON m.folder_id=f.id

apps/api/internal/app/types.go

@@ -21,8 +21,9 @@ type User struct {
 
 type AdminUser struct {
 	User
-	MailboxCount int      `json:"mailboxCount"`
-	Mailboxes    []string `json:"mailboxes"`
+	MailboxCount   int      `json:"mailboxCount"`
+	Mailboxes      []string `json:"mailboxes"`
+	StorageQuotaMB int      `json:"storageQuotaMb"`
 }
 
 type APIToken struct {
@@ -71,6 +72,7 @@ type Mailbox struct {
 	DisplayName string    `json:"displayName"`
 	QuotaMB     int       `json:"quotaMb"`
 	Status      string    `json:"status"`
+	Primary     bool      `json:"primary"`
 	UnreadCount int       `json:"unreadCount"`
 	CreatedAt   time.Time `json:"createdAt"`
 }