feat(panel): add domain-admin role with per-domain authorization

Co-authored-by: Cursor <cursoragent@cursor.com>

CHANGELOG.md

@@ -5,6 +5,22 @@ Format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/); version
 
 ## [Unreleased]
 
+### Added
+
+- panel: **domain-admin role** — global administrators manage panel users and
+  assign domains; domain administrators see only their domains (applications,
+  DKIM/DNS, per-domain DMARC, deliveries, export, L2 limits). Status, full
+  backup, mail queue, system log, domain add/delete, and `/reload` stay
+  global-only. SQLite migration `0005_panel_users` migrates the single
+  administrator into a global user; sessions and full backup restore carry users
+  and domain bindings.
+
+### Changed
+
+- panel: `/` redirects domain administrators to `/domains`; global users still
+  land on `/status`. Navigation hides global-only sections for domain
+  administrators.
+
 ## [1.1.0] - 2026-08-10
 
 The first MINOR after 1.0.0: send-only DMARC guidance in the panel, AGPL

internal/store/admin.go

@@ -1,85 +0,0 @@
-package store
-
-import (
-	"database/sql"
-	"errors"
-	"fmt"
-	"time"
-)
-
-// ErrNoAdmin is returned by GetAdmin when primary setup has not happened yet.
-var ErrNoAdmin = errors.New("no administrator account")
-
-// Admin is the single panel administrator (security.md).
-type Admin struct {
-	Username         string
-	PasswordHash     string
-	DMARCReportEmail string // default rua= for all sending domains; empty = none
-	CreatedAt        time.Time
-}
-
-// AdminExists reports whether the administrator account has been created. This
-// doubles as the "primary setup complete" flag: once true, the /setup route is
-// permanently gone (security.md).
-func (s *Store) AdminExists() (bool, error) {
-	var n int
-	if err := s.db.QueryRow("SELECT COUNT(*) FROM admin").Scan(&n); err != nil {
-		return false, fmt.Errorf("count admin: %w", err)
-	}
-	return n > 0, nil
-}
-
-// CreateAdmin inserts the administrator row. It fails if one already exists,
-// which — combined with the id=1 constraint — makes admin creation one-shot
-// even under a race between two setup submissions.
-func (s *Store) CreateAdmin(username, passwordHash string) error {
-	_, err := s.db.Exec(
-		"INSERT INTO admin (id, username, password_hash, created_at) VALUES (1, ?, ?, ?)",
-		username, passwordHash, time.Now().UTC().Format(time.RFC3339),
-	)
-	if err != nil {
-		return fmt.Errorf("create admin: %w", err)
-	}
-	return nil
-}
-
-// UpdateAdmin replaces the administrator's username and password hash. It
-// touches only the admin row (id = 1): panel credentials are unrelated to the
-// SASL logins applications authenticate with, which live in their own table.
-// ErrNoAdmin is returned if setup has not happened yet, so a change can never
-// silently create an account.
-func (s *Store) UpdateAdmin(username, passwordHash, dmarcReportEmail string) error {
-	res, err := s.db.Exec(
-		"UPDATE admin SET username = ?, password_hash = ?, dmarc_report_email = ? WHERE id = 1",
-		username, passwordHash, dmarcReportEmail,
-	)
-	if err != nil {
-		return fmt.Errorf("update admin: %w", err)
-	}
-	n, err := res.RowsAffected()
-	if err != nil {
-		return fmt.Errorf("update admin: %w", err)
-	}
-	if n == 0 {
-		return ErrNoAdmin
-	}
-	return nil
-}
-
-// GetAdmin returns the administrator account, or ErrNoAdmin if setup is pending.
-func (s *Store) GetAdmin() (Admin, error) {
-	var (
-		a         Admin
-		createdAt string
-	)
-	err := s.db.QueryRow("SELECT username, password_hash, dmarc_report_email, created_at FROM admin WHERE id = 1").
-		Scan(&a.Username, &a.PasswordHash, &a.DMARCReportEmail, &createdAt)
-	if errors.Is(err, sql.ErrNoRows) {
-		return Admin{}, ErrNoAdmin
-	}
-	if err != nil {
-		return Admin{}, fmt.Errorf("get admin: %w", err)
-	}
-	a.CreatedAt, _ = time.Parse(time.RFC3339, createdAt)
-	return a, nil
-}

internal/store/admin_test.go

@@ -1,56 +0,0 @@
-package store
-
-import (
-	"errors"
-	"testing"
-)
-
-func TestUpdateAdmin(t *testing.T) {
-	st := openTestStore(t)
-
-	if err := st.CreateAdmin("admin", "hash-one"); err != nil {
-		t.Fatalf("CreateAdmin: %v", err)
-	}
-	if err := st.UpdateAdmin("operator", "hash-two", "reports@hub.example"); err != nil {
-		t.Fatalf("UpdateAdmin: %v", err)
-	}
-
-	a, err := st.GetAdmin()
-	if err != nil {
-		t.Fatalf("GetAdmin: %v", err)
-	}
-	if a.DMARCReportEmail != "reports@hub.example" {
-		t.Fatalf("dmarc email = %q", a.DMARCReportEmail)
-	}
-
-	if err := st.UpdateAdmin("operator", "hash-three", ""); err != nil {
-		t.Fatalf("clear dmarc email: %v", err)
-	}
-	a, err = st.GetAdmin()
-	if err != nil {
-		t.Fatalf("GetAdmin: %v", err)
-	}
-	if a.Username != "operator" || a.PasswordHash != "hash-three" {
-		t.Fatalf("unexpected admin after update: %+v", a)
-	}
-	if a.CreatedAt.IsZero() {
-		t.Fatal("update dropped created_at")
-	}
-}
-
-// An update before setup must not create the account: only the one-time setup
-// flow may do that (security.md).
-func TestUpdateAdminWithoutAdmin(t *testing.T) {
-	st := openTestStore(t)
-
-	if err := st.UpdateAdmin("operator", "hash", ""); !errors.Is(err, ErrNoAdmin) {
-		t.Fatalf("UpdateAdmin without admin = %v, want ErrNoAdmin", err)
-	}
-	exists, err := st.AdminExists()
-	if err != nil {
-		t.Fatalf("AdminExists: %v", err)
-	}
-	if exists {
-		t.Fatal("UpdateAdmin created an administrator")
-	}
-}

internal/store/migrations/0005_panel_users.sql

@@ -0,0 +1,26 @@
+-- Panel users and domain-admin assignments. Migrates the single admin row into
+-- a global user; drops the admin table.
+
+CREATE TABLE users (
+    id                  INTEGER PRIMARY KEY AUTOINCREMENT,
+    username            TEXT NOT NULL UNIQUE,
+    password_hash       TEXT NOT NULL,
+    role                TEXT NOT NULL CHECK (role IN ('global', 'domain_admin')),
+    dmarc_report_email  TEXT NOT NULL DEFAULT '',
+    created_at          TEXT NOT NULL
+);
+
+CREATE TABLE user_domains (
+    user_id   INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    domain_id INTEGER NOT NULL REFERENCES domains(id) ON DELETE CASCADE,
+    PRIMARY KEY (user_id, domain_id)
+);
+
+INSERT INTO users (username, password_hash, role, dmarc_report_email, created_at)
+SELECT username, password_hash, 'global', dmarc_report_email, created_at
+FROM admin WHERE id = 1;
+
+INSERT OR REPLACE INTO settings (key, value)
+SELECT 'dmarc_report_email', dmarc_report_email FROM admin WHERE id = 1;
+
+DROP TABLE admin;

internal/store/settings.go

@@ -0,0 +1,32 @@
+package store
+
+import (
+	"database/sql"
+	"errors"
+	"fmt"
+)
+
+// GetSetting returns a settings value or empty string when missing.
+func (s *Store) GetSetting(key string) (string, error) {
+	var value string
+	err := s.db.QueryRow("SELECT value FROM settings WHERE key = ?", key).Scan(&value)
+	if errors.Is(err, sql.ErrNoRows) {
+		return "", nil
+	}
+	if err != nil {
+		return "", fmt.Errorf("get setting %s: %w", key, err)
+	}
+	return value, nil
+}
+
+// SetSetting upserts a settings key.
+func (s *Store) SetSetting(key, value string) error {
+	_, err := s.db.Exec(
+		"INSERT INTO settings (key, value) VALUES (?, ?) ON CONFLICT(key) DO UPDATE SET value = excluded.value",
+		key, value,
+	)
+	if err != nil {
+		return fmt.Errorf("set setting %s: %w", key, err)
+	}
+	return nil
+}

internal/store/users.go

@@ -0,0 +1,364 @@
+package store
+
+import (
+	"database/sql"
+	"errors"
+	"fmt"
+	"time"
+)
+
+// ErrNoUser is returned when primary setup has not happened yet.
+var ErrNoUser = errors.New("no panel user")
+
+// ErrUserNotFound is returned when a panel user id or username does not exist.
+var ErrUserNotFound = errors.New("user not found")
+
+// ErrUserExists is returned when a username is already taken.
+var ErrUserExists = errors.New("username already taken")
+
+// ErrLastGlobal is returned when deleting or demoting the last global user.
+var ErrLastGlobal = errors.New("cannot remove last global administrator")
+
+// Role identifies a panel user's access level.
+type Role string
+
+const (
+	RoleGlobal      Role = "global"
+	RoleDomainAdmin Role = "domain_admin"
+)
+
+// User is a panel login (not an application SASL account).
+type User struct {
+	ID               int64
+	Username         string
+	PasswordHash     string
+	Role             Role
+	DMARCReportEmail string
+	CreatedAt        time.Time
+	DomainIDs        []int64
+}
+
+// UserExists reports whether any panel user exists (setup complete).
+func (s *Store) UserExists() (bool, error) {
+	var n int
+	if err := s.db.QueryRow("SELECT COUNT(*) FROM users").Scan(&n); err != nil {
+		return false, fmt.Errorf("count users: %w", err)
+	}
+	return n > 0, nil
+}
+
+// CreateGlobalUser inserts the first global user during setup.
+func (s *Store) CreateGlobalUser(username, passwordHash string) error {
+	exists, err := s.UserExists()
+	if err != nil {
+		return err
+	}
+	if exists {
+		return fmt.Errorf("create global user: users already exist")
+	}
+	now := time.Now().UTC().Format(time.RFC3339)
+	_, err = s.db.Exec(
+		"INSERT INTO users (username, password_hash, role, dmarc_report_email, created_at) VALUES (?, ?, ?, '', ?)",
+		username, passwordHash, RoleGlobal, now,
+	)
+	if err != nil {
+		return fmt.Errorf("create global user: %w", err)
+	}
+	return nil
+}
+
+// GetUserByUsername returns a user with domain assignments loaded.
+func (s *Store) GetUserByUsername(username string) (User, error) {
+	var (
+		u         User
+		createdAt string
+	)
+	err := s.db.QueryRow(
+		"SELECT id, username, password_hash, role, dmarc_report_email, created_at FROM users WHERE username = ?",
+		username,
+	).Scan(&u.ID, &u.Username, &u.PasswordHash, &u.Role, &u.DMARCReportEmail, &createdAt)
+	if errors.Is(err, sql.ErrNoRows) {
+		return User{}, ErrUserNotFound
+	}
+	if err != nil {
+		return User{}, fmt.Errorf("get user by username: %w", err)
+	}
+	u.CreatedAt, _ = time.Parse(time.RFC3339, createdAt)
+	u.DomainIDs, err = s.listUserDomainIDs(u.ID)
+	if err != nil {
+		return User{}, err
+	}
+	return u, nil
+}
+
+// GetUser returns a user by id with domain assignments.
+func (s *Store) GetUser(id int64) (User, error) {
+	var (
+		u         User
+		createdAt string
+	)
+	err := s.db.QueryRow(
+		"SELECT id, username, password_hash, role, dmarc_report_email, created_at FROM users WHERE id = ?",
+		id,
+	).Scan(&u.ID, &u.Username, &u.PasswordHash, &u.Role, &u.DMARCReportEmail, &createdAt)
+	if errors.Is(err, sql.ErrNoRows) {
+		return User{}, ErrUserNotFound
+	}
+	if err != nil {
+		return User{}, fmt.Errorf("get user: %w", err)
+	}
+	u.CreatedAt, _ = time.Parse(time.RFC3339, createdAt)
+	u.DomainIDs, err = s.listUserDomainIDs(u.ID)
+	if err != nil {
+		return User{}, err
+	}
+	return u, nil
+}
+
+// ListUsers returns every panel user without domain ids.
+func (s *Store) ListUsers() ([]User, error) {
+	rows, err := s.db.Query(
+		"SELECT id, username, password_hash, role, dmarc_report_email, created_at FROM users ORDER BY id",
+	)
+	if err != nil {
+		return nil, fmt.Errorf("list users: %w", err)
+	}
+	defer rows.Close()
+	var users []User
+	for rows.Next() {
+		var (
+			u         User
+			createdAt string
+		)
+		if err := rows.Scan(&u.ID, &u.Username, &u.PasswordHash, &u.Role, &u.DMARCReportEmail, &createdAt); err != nil {
+			return nil, fmt.Errorf("list users scan: %w", err)
+		}
+		u.CreatedAt, _ = time.Parse(time.RFC3339, createdAt)
+		users = append(users, u)
+	}
+	return users, rows.Err()
+}
+
+// UserRow is a user plus assigned domain names for the management list.
+type UserRow struct {
+	User        User
+	DomainNames []string
+}
+
+// ListUserRows returns users with assigned domain names for the management UI.
+func (s *Store) ListUserRows() ([]UserRow, error) {
+	users, err := s.ListUsers()
+	if err != nil {
+		return nil, err
+	}
+	rows := make([]UserRow, len(users))
+	for i, u := range users {
+		rows[i].User = u
+		if u.Role == RoleGlobal {
+			continue
+		}
+		names, err := s.listUserDomainNames(u.ID)
+		if err != nil {
+			return nil, err
+		}
+		rows[i].DomainNames = names
+	}
+	return rows, nil
+}
+
+// CountGlobalUsers returns how many global-role users exist.
+func (s *Store) CountGlobalUsers() (int, error) {
+	var n int
+	if err := s.db.QueryRow("SELECT COUNT(*) FROM users WHERE role = ?", RoleGlobal).Scan(&n); err != nil {
+		return 0, fmt.Errorf("count global users: %w", err)
+	}
+	return n, nil
+}
+
+// CreateUser inserts a panel user and optional domain assignments.
+func (s *Store) CreateUser(username, passwordHash string, role Role, domainIDs []int64) (int64, error) {
+	if role == RoleDomainAdmin && len(domainIDs) == 0 {
+		return 0, fmt.Errorf("create user: domain_admin requires domains")
+	}
+	now := time.Now().UTC().Format(time.RFC3339)
+	res, err := s.db.Exec(
+		"INSERT INTO users (username, password_hash, role, dmarc_report_email, created_at) VALUES (?, ?, ?, '', ?)",
+		username, passwordHash, role, now,
+	)
+	if err != nil {
+		if isUniqueViolation(err) {
+			return 0, ErrUserExists
+		}
+		return 0, fmt.Errorf("create user: %w", err)
+	}
+	id, err := res.LastInsertId()
+	if err != nil {
+		return 0, fmt.Errorf("create user id: %w", err)
+	}
+	if role == RoleDomainAdmin {
+		if err := s.setUserDomains(id, domainIDs); err != nil {
+			return 0, err
+		}
+	}
+	return id, nil
+}
+
+// UpdateUser replaces username, password hash, and DMARC email for a user.
+func (s *Store) UpdateUser(id int64, username, passwordHash, dmarcReportEmail string) error {
+	u, err := s.GetUser(id)
+	if err != nil {
+		return err
+	}
+	res, err := s.db.Exec(
+		"UPDATE users SET username = ?, password_hash = ?, dmarc_report_email = ? WHERE id = ?",
+		username, passwordHash, dmarcReportEmail, id,
+	)
+	if err != nil {
+		if isUniqueViolation(err) {
+			return ErrUserExists
+		}
+		return fmt.Errorf("update user: %w", err)
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return fmt.Errorf("update user: %w", err)
+	}
+	if n == 0 {
+		return ErrUserNotFound
+	}
+	if u.Role == RoleGlobal {
+		if err := s.SetSetting("dmarc_report_email", dmarcReportEmail); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// SetUserRole updates a user's role.
+func (s *Store) SetUserRole(userID int64, role Role) error {
+	res, err := s.db.Exec("UPDATE users SET role = ? WHERE id = ?", role, userID)
+	if err != nil {
+		return fmt.Errorf("set user role: %w", err)
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return fmt.Errorf("set user role: %w", err)
+	}
+	if n == 0 {
+		return ErrUserNotFound
+	}
+	return nil
+}
+
+// ClearUserDomains removes all domain assignments for a user.
+func (s *Store) ClearUserDomains(userID int64) error {
+	_, err := s.db.Exec("DELETE FROM user_domains WHERE user_id = ?", userID)
+	if err != nil {
+		return fmt.Errorf("clear user domains: %w", err)
+	}
+	return nil
+}
+
+// SetUserDomains replaces domain assignments for a domain_admin user.
+func (s *Store) SetUserDomains(userID int64, domainIDs []int64) error {
+	u, err := s.GetUser(userID)
+	if err != nil {
+		return err
+	}
+	if u.Role != RoleDomainAdmin {
+		return fmt.Errorf("set user domains: user is not domain_admin")
+	}
+	if len(domainIDs) == 0 {
+		return fmt.Errorf("set user domains: at least one domain required")
+	}
+	return s.setUserDomains(userID, domainIDs)
+}
+
+// DeleteUser removes a panel user. ErrLastGlobal when deleting the only global user.
+func (s *Store) DeleteUser(id int64) error {
+	u, err := s.GetUser(id)
+	if err != nil {
+		return err
+	}
+	if u.Role == RoleGlobal {
+		n, err := s.CountGlobalUsers()
+		if err != nil {
+			return err
+		}
+		if n <= 1 {
+			return ErrLastGlobal
+		}
+	}
+	res, err := s.db.Exec("DELETE FROM users WHERE id = ?", id)
+	if err != nil {
+		return fmt.Errorf("delete user: %w", err)
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return fmt.Errorf("delete user: %w", err)
+	}
+	if n == 0 {
+		return ErrUserNotFound
+	}
+	return nil
+}
+
+// GlobalDMARCReportEmail returns the shared default rua= for domain inherit mode.
+func (s *Store) GlobalDMARCReportEmail() (string, error) {
+	return s.GetSetting("dmarc_report_email")
+}
+
+func (s *Store) listUserDomainIDs(userID int64) ([]int64, error) {
+	rows, err := s.db.Query("SELECT domain_id FROM user_domains WHERE user_id = ? ORDER BY domain_id", userID)
+	if err != nil {
+		return nil, fmt.Errorf("list user domains: %w", err)
+	}
+	defer rows.Close()
+	var ids []int64
+	for rows.Next() {
+		var id int64
+		if err := rows.Scan(&id); err != nil {
+			return nil, fmt.Errorf("list user domains scan: %w", err)
+		}
+		ids = append(ids, id)
+	}
+	return ids, rows.Err()
+}
+
+func (s *Store) listUserDomainNames(userID int64) ([]string, error) {
+	rows, err := s.db.Query(
+		"SELECT d.name FROM user_domains ud JOIN domains d ON d.id = ud.domain_id WHERE ud.user_id = ? ORDER BY d.name",
+		userID,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("list user domain names: %w", err)
+	}
+	defer rows.Close()
+	var names []string
+	for rows.Next() {
+		var name string
+		if err := rows.Scan(&name); err != nil {
+			return nil, fmt.Errorf("list user domain names scan: %w", err)
+		}
+		names = append(names, name)
+	}
+	return names, rows.Err()
+}
+
+func (s *Store) setUserDomains(userID int64, domainIDs []int64) error {
+	tx, err := s.db.Begin()
+	if err != nil {
+		return fmt.Errorf("set user domains begin: %w", err)
+	}
+	if _, err := tx.Exec("DELETE FROM user_domains WHERE user_id = ?", userID); err != nil {
+		tx.Rollback()
+		return fmt.Errorf("set user domains clear: %w", err)
+	}
+	for _, did := range domainIDs {
+		if _, err := tx.Exec("INSERT INTO user_domains (user_id, domain_id) VALUES (?, ?)", userID, did); err != nil {
+			tx.Rollback()
+			return fmt.Errorf("set user domains insert: %w", err)
+		}
+	}
+	return tx.Commit()
+}

internal/store/users_test.go

@@ -0,0 +1,101 @@
+package store
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestUpdateUser(t *testing.T) {
+	st := openTestStore(t)
+
+	if err := st.CreateGlobalUser("admin", "hash-one"); err != nil {
+		t.Fatalf("CreateGlobalUser: %v", err)
+	}
+	u, err := st.GetUserByUsername("admin")
+	if err != nil {
+		t.Fatalf("GetUserByUsername: %v", err)
+	}
+	if err := st.UpdateUser(u.ID, "operator", "hash-two", "reports@hub.example"); err != nil {
+		t.Fatalf("UpdateUser: %v", err)
+	}
+
+	got, err := st.GetUser(u.ID)
+	if err != nil {
+		t.Fatalf("GetUser: %v", err)
+	}
+	if got.DMARCReportEmail != "reports@hub.example" {
+		t.Fatalf("dmarc email = %q", got.DMARCReportEmail)
+	}
+	email, err := st.GlobalDMARCReportEmail()
+	if err != nil {
+		t.Fatalf("GlobalDMARCReportEmail: %v", err)
+	}
+	if email != "reports@hub.example" {
+		t.Fatalf("settings dmarc = %q", email)
+	}
+
+	if err := st.UpdateUser(u.ID, "operator", "hash-three", ""); err != nil {
+		t.Fatalf("clear dmarc email: %v", err)
+	}
+	got, err = st.GetUser(u.ID)
+	if err != nil {
+		t.Fatalf("GetUser: %v", err)
+	}
+	if got.Username != "operator" || got.PasswordHash != "hash-three" {
+		t.Fatalf("unexpected user after update: %+v", got)
+	}
+	if got.CreatedAt.IsZero() {
+		t.Fatal("update dropped created_at")
+	}
+}
+
+func TestUpdateUserWithoutUser(t *testing.T) {
+	st := openTestStore(t)
+
+	if err := st.UpdateUser(1, "operator", "hash", ""); !errors.Is(err, ErrUserNotFound) {
+		t.Fatalf("UpdateUser without user = %v, want ErrUserNotFound", err)
+	}
+	exists, err := st.UserExists()
+	if err != nil {
+		t.Fatalf("UserExists: %v", err)
+	}
+	if exists {
+		t.Fatal("UpdateUser created a user")
+	}
+}
+
+func TestCreateDomainAdminUser(t *testing.T) {
+	st := openTestStore(t)
+	if err := st.CreateGlobalUser("admin", "hash"); err != nil {
+		t.Fatalf("CreateGlobalUser: %v", err)
+	}
+	d, err := st.AddDomain("example.com", "s1")
+	if err != nil {
+		t.Fatalf("AddDomain: %v", err)
+	}
+	id, err := st.CreateUser("domainop", "hash2", RoleDomainAdmin, []int64{d.ID})
+	if err != nil {
+		t.Fatalf("CreateUser: %v", err)
+	}
+	u, err := st.GetUser(id)
+	if err != nil {
+		t.Fatalf("GetUser: %v", err)
+	}
+	if len(u.DomainIDs) != 1 || u.DomainIDs[0] != d.ID {
+		t.Fatalf("domain ids = %v, want [%d]", u.DomainIDs, d.ID)
+	}
+}
+
+func TestDeleteLastGlobalUser(t *testing.T) {
+	st := openTestStore(t)
+	if err := st.CreateGlobalUser("admin", "hash"); err != nil {
+		t.Fatalf("CreateGlobalUser: %v", err)
+	}
+	u, err := st.GetUserByUsername("admin")
+	if err != nil {
+		t.Fatalf("GetUserByUsername: %v", err)
+	}
+	if err := st.DeleteUser(u.ID); !errors.Is(err, ErrLastGlobal) {
+		t.Fatalf("DeleteUser = %v, want ErrLastGlobal", err)
+	}
+}

internal/web/auth/handlers.go

@@ -61,7 +61,7 @@ func (m *Module) clearSessionCookies(w http.ResponseWriter) {
 
 // HandleLogin serves the login form (GET) and authenticates (POST).
 func (m *Module) HandleLogin(w http.ResponseWriter, r *http.Request) {
-	exists, err := m.store.AdminExists()
+	exists, err := m.store.UserExists()
 	if err != nil {
 		http.Error(w, "internal error", http.StatusInternalServerError)
 		return
@@ -106,22 +106,21 @@ func (m *Module) submitLogin(w http.ResponseWriter, r *http.Request) {
 	username := strings.TrimSpace(r.PostFormValue("username"))
 	password := r.PostFormValue("password")
 
-	admin, err := m.store.GetAdmin()
+	user, err := m.store.GetUserByUsername(username)
 	if err != nil {
-		if !errors.Is(err, store.ErrNoAdmin) {
-			logf("panel: login: get admin failed: %v", err)
+		if !errors.Is(err, store.ErrUserNotFound) {
+			logf("panel: login: get user failed: %v", err)
 		}
 		m.renderLogin(w, http.StatusUnauthorized, "Invalid username or password.")
 		return
 	}
 
-	pwErr := bcrypt.CompareHashAndPassword([]byte(admin.PasswordHash), []byte(password))
-	if username != admin.Username || pwErr != nil {
+	if err := bcrypt.CompareHashAndPassword([]byte(user.PasswordHash), []byte(password)); err != nil {
 		m.renderLogin(w, http.StatusUnauthorized, "Invalid username or password.")
 		return
 	}
 
-	token := m.sessions.Create(admin.Username)
+	token := m.sessions.Create(user.Username)
 	m.setSessionCookie(w, token)
 	http.Redirect(w, r, "/", http.StatusSeeOther)
 }
@@ -222,13 +221,13 @@ func (m *Module) submitSetup(w http.ResponseWriter, r *http.Request, token strin
 		return
 	}
 
-	if err := m.store.CreateAdmin(username, string(hash)); err != nil {
-		if exists, _ := m.store.AdminExists(); exists {
+	if err := m.store.CreateGlobalUser(username, string(hash)); err != nil {
+		if exists, _ := m.store.UserExists(); exists {
 			m.setup.complete()
 			http.Redirect(w, r, "/login", http.StatusSeeOther)
 			return
 		}
-		logf("panel: setup: create admin failed: %v", err)
+		logf("panel: setup: create user failed: %v", err)
 		m.renderSetupForm(w, http.StatusInternalServerError, token, "Internal error. Please try again.")
 		return
 	}

internal/web/auth/middleware.go

@@ -1,17 +1,12 @@
 package auth
 
 import (
-	"context"
 	"net/http"
 )
 
-type ctxKey int
-
-const usernameKey ctxKey = 0
-
 // RequireAuth wraps a handler so only requests with a valid session cookie
 // reach it; everyone else is redirected to the login page. The authenticated
-// username is stashed in the request context for downstream handlers.
+// principal is stashed in the request context for downstream handlers.
 func (m *Module) RequireAuth(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		token, ok := m.sessionToken(r)
@@ -27,7 +22,13 @@ func (m *Module) RequireAuth(next http.Handler) http.Handler {
 		if isSessionActivity(r) && m.sessions.Touch(token) {
 			m.setSessionCookie(w, token)
 		}
-		ctx := context.WithValue(r.Context(), usernameKey, username)
+		u, err := m.store.GetUserByUsername(username)
+		if err != nil {
+			http.Redirect(w, r, "/login", http.StatusSeeOther)
+			return
+		}
+		p := principalFromUser(u)
+		ctx := withPrincipal(r.Context(), p)
 		next.ServeHTTP(w, r.WithContext(ctx))
 	})
 }
@@ -43,3 +44,15 @@ func CurrentUser(r *http.Request) string {
 	}
 	return ""
 }
+
+// RequireGlobal wraps a handler that only global administrators may reach.
+func RequireGlobal(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		p, ok := CurrentPrincipal(r.Context())
+		if !ok || !p.IsGlobal() {
+			http.NotFound(w, r)
+			return
+		}
+		next.ServeHTTP(w, r)
+	})
+}

internal/web/auth/principal.go

@@ -0,0 +1,86 @@
+package auth
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/mixeme/selfpost/internal/store"
+)
+
+type ctxKey int
+
+const (
+	usernameKey   ctxKey = 0
+	principalKey  ctxKey = 1
+)
+
+// Role is a panel user's access level.
+type Role = store.Role
+
+const (
+	RoleGlobal      = store.RoleGlobal
+	RoleDomainAdmin = store.RoleDomainAdmin
+)
+
+// Principal is the authenticated panel user attached to a request.
+type Principal struct {
+	ID       int64
+	Username string
+	Role     Role
+	Domains  []int64 // assigned domain IDs; empty for global (all domains)
+}
+
+// IsGlobal reports whether the principal has full panel access.
+func (p Principal) IsGlobal() bool {
+	return p.Role == RoleGlobal
+}
+
+// CanAccessDomain reports whether the principal may access a domain id.
+func (p Principal) CanAccessDomain(domainID int64) bool {
+	if p.IsGlobal() {
+		return true
+	}
+	for _, id := range p.Domains {
+		if id == domainID {
+			return true
+		}
+	}
+	return false
+}
+
+// CanAccessApp reports whether the principal may access an application.
+func (p Principal) CanAccessApp(app store.Application) bool {
+	return p.CanAccessDomain(app.DomainID)
+}
+
+func principalFromUser(u store.User) Principal {
+	return Principal{
+		ID:       u.ID,
+		Username: u.Username,
+		Role:     u.Role,
+		Domains:  u.DomainIDs,
+	}
+}
+
+func withPrincipal(ctx context.Context, p Principal) context.Context {
+	ctx = context.WithValue(ctx, usernameKey, p.Username)
+	return context.WithValue(ctx, principalKey, p)
+}
+
+// CurrentPrincipal returns the authenticated principal from the request context.
+func CurrentPrincipal(ctx context.Context) (Principal, bool) {
+	if v, ok := ctx.Value(principalKey).(Principal); ok {
+		return v, true
+	}
+	return Principal{}, false
+}
+
+// PrincipalFromRequest returns the authenticated principal from an HTTP request.
+func PrincipalFromRequest(r *http.Request) (Principal, bool) {
+	return CurrentPrincipal(r.Context())
+}
+
+// RequestWithPrincipal attaches a principal for middleware-equivalent tests.
+func RequestWithPrincipal(r *http.Request, p Principal) *http.Request {
+	return r.WithContext(withPrincipal(r.Context(), p))
+}

internal/web/auth/setup.go

@@ -33,7 +33,7 @@ func newSetupManager(st *store.Store, hostname, tokenPath string) *setupManager
 }
 
 func (m *setupManager) bootstrap() error {
-	done, err := m.store.AdminExists()
+	done, err := m.store.UserExists()
 	if err != nil {
 		return err
 	}
@@ -48,9 +48,9 @@ func (m *setupManager) bootstrap() error {
 }
 
 func (m *setupManager) activeToken() (string, bool) {
-	done, err := m.store.AdminExists()
+	done, err := m.store.UserExists()
 	if err != nil {
-		logf("panel: setup: admin check failed: %v", err)
+		logf("panel: setup: user check failed: %v", err)
 		return "", false
 	}
 	if done {

internal/web/handlers/authz.go

@@ -0,0 +1,65 @@
+package handlers
+
+import (
+	"net/http"
+
+	"github.com/mixeme/selfpost/internal/store"
+	"github.com/mixeme/selfpost/internal/web/auth"
+)
+
+func (h *Handlers) principal(r *http.Request) (auth.Principal, bool) {
+	return auth.PrincipalFromRequest(r)
+}
+
+func (h *Handlers) requireGlobal(w http.ResponseWriter, r *http.Request) (auth.Principal, bool) {
+	p, ok := h.principal(r)
+	if !ok || !p.IsGlobal() {
+		http.NotFound(w, r)
+		return auth.Principal{}, false
+	}
+	return p, true
+}
+
+func (h *Handlers) pageBase(r *http.Request) map[string]any {
+	p, _ := h.principal(r)
+	return map[string]any{
+		"User":     auth.CurrentUser(r),
+		"IsGlobal": p.IsGlobal(),
+	}
+}
+
+func (h *Handlers) assignedDomains(p auth.Principal) ([]store.Domain, error) {
+	if p.IsGlobal() {
+		return h.store.ListDomains()
+	}
+	all, err := h.store.ListDomains()
+	if err != nil {
+		return nil, err
+	}
+	var out []store.Domain
+	for _, d := range all {
+		if p.CanAccessDomain(d.ID) {
+			out = append(out, d)
+		}
+	}
+	return out, nil
+}
+
+func domainNameSet(domains []store.Domain) map[string]bool {
+	m := make(map[string]bool, len(domains))
+	for _, d := range domains {
+		m[d.Name] = true
+	}
+	return m
+}
+
+func domainIDSet(p auth.Principal) map[int64]bool {
+	if p.IsGlobal() {
+		return nil
+	}
+	m := make(map[int64]bool, len(p.Domains))
+	for _, id := range p.Domains {
+		m[id] = true
+	}
+	return m
+}

internal/web/handlers/handlers_account.go

@@ -14,21 +14,22 @@ import (
 	"golang.org/x/crypto/bcrypt"
 )
 
-// HandleAccount serves the administrator's own account settings: the username
-// and password chosen during setup are the only panel credentials
-// (security.md), and until now they could be changed only by recreating the
-// state. Changing them here never touches application SASL logins, which are a
-// separate identity system (architecture.md § Mail path).
+// HandleAccount serves the signed-in user's account settings.
 func (h *Handlers) HandleAccount(w http.ResponseWriter, r *http.Request) {
 	switch r.Method {
 	case http.MethodGet:
-		admin, err := h.store.GetAdmin()
-		if err != nil {
-			logf("panel: account: get admin failed: %v", err)
+		p, ok := h.principal(r)
+		if !ok {
 			http.Error(w, "internal error", http.StatusInternalServerError)
 			return
 		}
-		h.renderAccount(w, r, http.StatusOK, "", admin.Username, admin.DMARCReportEmail)
+		u, err := h.store.GetUser(p.ID)
+		if err != nil {
+			logf("panel: account: get user failed: %v", err)
+			http.Error(w, "internal error", http.StatusInternalServerError)
+			return
+		}
+		h.renderAccount(w, r, http.StatusOK, "", u.Username, u.DMARCReportEmail, p.IsGlobal())
 	case http.MethodPost:
 		h.submitAccount(w, r)
 	default:
@@ -37,33 +38,30 @@ func (h *Handlers) HandleAccount(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
-// renderAccount draws the settings form. formUsername and formDMARCEmail
-// repopulate fields after a rejected submission; password fields are never
-// repopulated.
-func (h *Handlers) renderAccount(w http.ResponseWriter, r *http.Request, status int, formErr, formUsername, formDMARCEmail string) {
+func (h *Handlers) renderAccount(w http.ResponseWriter, r *http.Request, status int, formErr, formUsername, formDMARCEmail string, showDMARC bool) {
 	var reportAuth dnscheck.Result
-	if hub := dnscheck.EmailDomain(formDMARCEmail); hub != "" {
-		ctx, cancel := context.WithTimeout(r.Context(), 5*time.Second)
-		reportAuth = h.dns.ReportAuth(ctx, hub)
-		cancel()
+	if showDMARC && formDMARCEmail != "" {
+		if hub := dnscheck.EmailDomain(formDMARCEmail); hub != "" {
+			ctx, cancel := context.WithTimeout(r.Context(), 5*time.Second)
+			reportAuth = h.dns.ReportAuth(ctx, hub)
+			cancel()
+		}
 	}
-	h.view.Render(w, status, "account", map[string]any{
-		"Title":              "SelfPost — settings",
-		"User":               auth.CurrentUser(r),
-		"Active":             "account",
-		"FormUsername":       formUsername,
-		"FormDMARCEmail":     formDMARCEmail,
-		"ReportAuthName":     dnscheck.ReportAuthRecordName(dnscheck.EmailDomain(formDMARCEmail)),
-		"ReportAuthExample":  dnscheck.ReportAuthExample(),
-		"ReportAuthDNS":      reportAuth,
-		"ReportAuthHub":      dnscheck.EmailDomain(formDMARCEmail),
-		"Error":              formErr,
-		"Flash":              accountFlash(r),
-	})
+	data := h.pageBase(r)
+	data["Title"] = "SelfPost — settings"
+	data["Active"] = "account"
+	data["FormUsername"] = formUsername
+	data["FormDMARCEmail"] = formDMARCEmail
+	data["ShowDMARC"] = showDMARC
+	data["ReportAuthName"] = dnscheck.ReportAuthRecordName(dnscheck.EmailDomain(formDMARCEmail))
+	data["ReportAuthExample"] = dnscheck.ReportAuthExample()
+	data["ReportAuthDNS"] = reportAuth
+	data["ReportAuthHub"] = dnscheck.EmailDomain(formDMARCEmail)
+	data["Error"] = formErr
+	data["Flash"] = accountFlash(r)
+	h.view.Render(w, status, "account", data)
 }
 
-// accountFlash maps a fixed redirect flag to a fixed message, so status text
-// after a redirect is never attacker-influenced.
 func accountFlash(r *http.Request) string {
 	switch r.URL.Query().Get("updated") {
 	case "username":
@@ -85,19 +83,28 @@ func accountFlash(r *http.Request) string {
 	}
 }
 
-// submitAccount applies a username and/or password change. The current password
-// is always required, so a stolen session alone cannot lock the administrator
-// out of their own panel, and the attempt is throttled on the same limiter as
-// the login form so this route cannot be used to brute-force the password past
-// that limit (security.md).
 func (h *Handlers) submitAccount(w http.ResponseWriter, r *http.Request) {
 	if !h.auth.AllowLoginAttempt(r) {
+		p, _ := h.principal(r)
 		h.renderAccount(w, r, http.StatusTooManyRequests,
-			"Too many attempts. Please wait and try again.", auth.CurrentUser(r), "")
+			"Too many attempts. Please wait and try again.", auth.CurrentUser(r), "", p.IsGlobal())
 		return
 	}
 	if err := r.ParseForm(); err != nil {
-		h.renderAccount(w, r, http.StatusBadRequest, "Invalid form submission.", auth.CurrentUser(r), "")
+		p, _ := h.principal(r)
+		h.renderAccount(w, r, http.StatusBadRequest, "Invalid form submission.", auth.CurrentUser(r), "", p.IsGlobal())
+		return
+	}
+
+	p, ok := h.principal(r)
+	if !ok {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+	user, err := h.store.GetUser(p.ID)
+	if err != nil {
+		logf("panel: account: get user failed: %v", err)
+		http.Error(w, "internal error", http.StatusInternalServerError)
 		return
 	}
 
@@ -106,73 +113,76 @@ func (h *Handlers) submitAccount(w http.ResponseWriter, r *http.Request) {
 	password := r.PostFormValue("new_password")
 	confirm := r.PostFormValue("new_password_confirm")
 	dmarcEmail := strings.TrimSpace(r.PostFormValue("dmarc_report_email"))
-
-	admin, err := h.store.GetAdmin()
-	if err != nil {
-		logf("panel: account: get admin failed: %v", err)
-		http.Error(w, "internal error", http.StatusInternalServerError)
-		return
+	if !p.IsGlobal() {
+		dmarcEmail = user.DMARCReportEmail
 	}
 	if username == "" {
-		username = admin.Username
+		username = user.Username
 	}
 
-	if err := bcrypt.CompareHashAndPassword([]byte(admin.PasswordHash), []byte(current)); err != nil {
-		h.renderAccount(w, r, http.StatusUnauthorized, "Current password is incorrect.", username, dmarcEmail)
+	if err := bcrypt.CompareHashAndPassword([]byte(user.PasswordHash), []byte(current)); err != nil {
+		h.renderAccount(w, r, http.StatusUnauthorized, "Current password is incorrect.", username, dmarcEmail, p.IsGlobal())
 		return
 	}
 
-	renaming := username != admin.Username
+	renaming := username != user.Username
 	if renaming {
 		if err := validate.Username(username); err != nil {
-			h.renderAccount(w, r, http.StatusBadRequest, err.Error(), username, dmarcEmail)
+			h.renderAccount(w, r, http.StatusBadRequest, err.Error(), username, dmarcEmail, p.IsGlobal())
 			return
 		}
 	}
 
-	if err := validate.Email(dmarcEmail); err != nil {
-		h.renderAccount(w, r, http.StatusBadRequest, err.Error(), username, dmarcEmail)
-		return
+	if p.IsGlobal() {
+		if err := validate.Email(dmarcEmail); err != nil {
+			h.renderAccount(w, r, http.StatusBadRequest, err.Error(), username, dmarcEmail, true)
+			return
+		}
 	}
 
-	emailChanging := dmarcEmail != admin.DMARCReportEmail
+	emailChanging := p.IsGlobal() && dmarcEmail != user.DMARCReportEmail
 
 	repassword := password != "" || confirm != ""
 	if repassword {
 		if password != confirm {
-			h.renderAccount(w, r, http.StatusBadRequest, "New passwords do not match.", username, dmarcEmail)
+			h.renderAccount(w, r, http.StatusBadRequest, "New passwords do not match.", username, dmarcEmail, p.IsGlobal())
 			return
 		}
 		if err := validate.AdminPassword(password); err != nil {
-			h.renderAccount(w, r, http.StatusBadRequest, err.Error(), username, dmarcEmail)
+			h.renderAccount(w, r, http.StatusBadRequest, err.Error(), username, dmarcEmail, p.IsGlobal())
 			return
 		}
 	}
 	if !renaming && !repassword && !emailChanging {
 		h.renderAccount(w, r, http.StatusBadRequest,
-			"Nothing to change: enter a new username, password, or DMARC report address.", username, dmarcEmail)
+			"Nothing to change: enter a new username, password, or DMARC report address.", username, dmarcEmail, p.IsGlobal())
 		return
 	}
 
-	hash := admin.PasswordHash
+	hash := user.PasswordHash
 	if repassword {
 		newHash, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
 		if err != nil {
 			logf("panel: account: hashing password failed: %v", err)
 			h.renderAccount(w, r, http.StatusInternalServerError,
-				"Internal error. Please try again.", username, dmarcEmail)
+				"Internal error. Please try again.", username, dmarcEmail, p.IsGlobal())
 			return
 		}
 		hash = string(newHash)
 	}
 
-	if err := h.store.UpdateAdmin(username, hash, dmarcEmail); err != nil {
-		logf("panel: account: update admin failed: %v", err)
+	if err := h.store.UpdateUser(user.ID, username, hash, dmarcEmail); err != nil {
+		logf("panel: account: update user failed: %v", err)
 		msg := "Could not save the changes. Please check the logs and try again."
-		if errors.Is(err, store.ErrNoAdmin) {
-			msg = "There is no administrator account to update."
+		if errors.Is(err, store.ErrUserNotFound) {
+			msg = "There is no user account to update."
 		}
-		h.renderAccount(w, r, http.StatusInternalServerError, msg, username, dmarcEmail)
+		if errors.Is(err, store.ErrUserExists) {
+			msg = "That username is already in use."
+			h.renderAccount(w, r, http.StatusConflict, msg, username, dmarcEmail, p.IsGlobal())
+			return
+		}
+		h.renderAccount(w, r, http.StatusInternalServerError, msg, username, dmarcEmail, p.IsGlobal())
 		return
 	}
 
@@ -185,7 +195,7 @@ func (h *Handlers) submitAccount(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	logf("panel: administrator account updated (username: %t, password: %t, dmarc email: %t)", renaming, repassword, emailChanging)
+	logf("panel: user %d account updated (username: %t, password: %t, dmarc email: %t)", user.ID, renaming, repassword, emailChanging)
 	http.Redirect(w, r, "/account?updated="+updatedFlag(renaming, repassword, emailChanging), http.StatusSeeOther)
 }
 

internal/web/handlers/handlers_apps.go

@@ -10,7 +10,6 @@ import (
 	"github.com/mixeme/selfpost/internal/dnscheck"
 	"github.com/mixeme/selfpost/internal/domain"
 	"github.com/mixeme/selfpost/internal/store"
-	"github.com/mixeme/selfpost/internal/web/auth"
 	"github.com/mixeme/selfpost/internal/web/validate"
 )
 
@@ -104,13 +103,12 @@ func (h *Handlers) renderDomainDetail(w http.ResponseWriter, r *http.Request, st
 	// What DNS actually publishes for the domain today, checked against the key
 	// this server signs with. Cached by the checker, so re-rendering the page
 	// after a form post costs nothing.
-	admin, err := h.store.GetAdmin()
+	profileEmail, err := h.store.GlobalDMARCReportEmail()
 	if err != nil {
-		logf("panel: domain %d: get admin: %v", d.ID, err)
+		logf("panel: domain %d: global dmarc email: %v", d.ID, err)
 		http.Error(w, "internal error", http.StatusInternalServerError)
 		return
 	}
-	profileEmail := admin.DMARCReportEmail
 	reportEmail := dnscheck.ResolveDMARCRua(d.DMARCRua, profileEmail)
 	dns, srv := h.domainDNS(d, record, profileEmail, false)
 	reportAuthName, reportAuthValue, needsReportAuth := dnscheck.ExternalReportAuth(d.Name, reportEmail)
@@ -134,52 +132,43 @@ func (h *Handlers) renderDomainDetail(w http.ResponseWriter, r *http.Request, st
 		dmarcSource = "settings"
 	}
 
-	h.view.Render(w, status, "domain_detail", map[string]any{
-		"Title":  "SelfPost — " + d.Name,
-		"User":   auth.CurrentUser(r),
-		"Active": "domains",
-		"Domain": d,
-		"Record": record,
-		"DNS":    dns,
-		// SPF and DMARC are the operator's to write — SelfPost cannot generate
-		// them the way it generates the DKIM record — so the page shows what
-		// this server expects rather than leaving it to the documentation. The
-		// same builders phrase the suggestions in the check messages, so the
-		// page and the checks below it never recommend different records.
-		"SPFExample":   dnscheck.SPFExample(h.cfg.Hostname, srv.IPs),
-		"DMARCName":    dnscheck.DMARCRecordName(d.Name),
-		"DMARCExample":      dnscheck.DMARCExample(reportEmail),
-		"DMARCSource":       dmarcSource,
-		"ProfileDMARCEmail": profileEmail,
-		"ResolvedDMARCEmail": reportEmail,
-		"DMARCRuaMode":      dmarcMode,
-		"DMARCRuaCustom":    dmarcCustom,
-		"ReportAuthName":    reportAuthName,
-		"ReportAuthValue":   reportAuthValue,
-		"NeedsReportAuth":   needsReportAuth,
-		"SameDomainRUA":     reportEmail != "" && strings.EqualFold(dnscheck.EmailDomain(reportEmail), d.Name),
-		// Client connection settings (the same for every domain on this
-		// instance): the hostname clients connect to, and whether the optional
-		// submission listener is enabled in this deployment.
-		"Hostname":          h.cfg.Hostname,
-		"SubmissionEnabled": h.cfg.SubmissionEnabled,
-		"Apps":              appViews,
-		"Error":             view.FormErr,
-		"FormLogin":         view.FormLogin,
-		"FormMode":          view.FormMode,
-		"FormAddrs":         view.FormAddrs,
-		"NewCred":           view.NewCred,
-		"Flash":             detailFlash(r),
-		"Wildcard":          store.AddressModeWildcard,
-		"List":              store.AddressModeList,
-		"RateLimitErr":      view.RateLimitErr,
-		"ExportErr":         view.ExportErr,
-		"MinPwLen":          validate.MinSecretFilePasswordLen,
-		"DomainHasRL":       domainRLok && domainRL.Active(),
-		"DomainRLIPs":       strings.Join(domainRL.AllowedIPs, "\n"),
-		"DomainRLMax":       intOrBlank(domainRL.MaxMessages),
-		"DomainRLWin":       windowOrDefault(domainRL.WindowSeconds),
-	})
+	data := h.pageBase(r)
+	data["Title"] = "SelfPost — " + d.Name
+	data["Active"] = "domains"
+	data["Domain"] = d
+	data["Record"] = record
+	data["DNS"] = dns
+	data["SPFExample"] = dnscheck.SPFExample(h.cfg.Hostname, srv.IPs)
+	data["DMARCName"] = dnscheck.DMARCRecordName(d.Name)
+	data["DMARCExample"] = dnscheck.DMARCExample(reportEmail)
+	data["DMARCSource"] = dmarcSource
+	data["ProfileDMARCEmail"] = profileEmail
+	data["ResolvedDMARCEmail"] = reportEmail
+	data["DMARCRuaMode"] = dmarcMode
+	data["DMARCRuaCustom"] = dmarcCustom
+	data["ReportAuthName"] = reportAuthName
+	data["ReportAuthValue"] = reportAuthValue
+	data["NeedsReportAuth"] = needsReportAuth
+	data["SameDomainRUA"] = reportEmail != "" && strings.EqualFold(dnscheck.EmailDomain(reportEmail), d.Name)
+	data["Hostname"] = h.cfg.Hostname
+	data["SubmissionEnabled"] = h.cfg.SubmissionEnabled
+	data["Apps"] = appViews
+	data["Error"] = view.FormErr
+	data["FormLogin"] = view.FormLogin
+	data["FormMode"] = view.FormMode
+	data["FormAddrs"] = view.FormAddrs
+	data["NewCred"] = view.NewCred
+	data["Flash"] = detailFlash(r)
+	data["Wildcard"] = store.AddressModeWildcard
+	data["List"] = store.AddressModeList
+	data["RateLimitErr"] = view.RateLimitErr
+	data["ExportErr"] = view.ExportErr
+	data["MinPwLen"] = validate.MinSecretFilePasswordLen
+	data["DomainHasRL"] = domainRLok && domainRL.Active()
+	data["DomainRLIPs"] = strings.Join(domainRL.AllowedIPs, "\n")
+	data["DomainRLMax"] = intOrBlank(domainRL.MaxMessages)
+	data["DomainRLWin"] = windowOrDefault(domainRL.WindowSeconds)
+	h.view.Render(w, status, "domain_detail", data)
 }
 
 // domainDNS resolves what the world sees for a domain: its DKIM, SPF and DMARC
@@ -213,13 +202,13 @@ func (h *Handlers) HandleDomainDNSRecheck(w http.ResponseWriter, r *http.Request
 		http.Error(w, "internal error", http.StatusInternalServerError)
 		return
 	}
-	admin, err := h.store.GetAdmin()
+	profileEmail, err := h.store.GlobalDMARCReportEmail()
 	if err != nil {
-		logf("panel: domain %d: get admin: %v", d.ID, err)
+		logf("panel: domain %d: global dmarc email: %v", d.ID, err)
 		http.Error(w, "internal error", http.StatusInternalServerError)
 		return
 	}
-	h.domainDNS(d, record, admin.DMARCReportEmail, true)
+	h.domainDNS(d, record, profileEmail, true)
 	http.Redirect(w, r, fmt.Sprintf("/domains/%d?rechecked=1", d.ID), http.StatusSeeOther)
 }
 
@@ -387,6 +376,11 @@ func (h *Handlers) lookupApplication(w http.ResponseWriter, r *http.Request) (st
 		http.Error(w, "internal error", http.StatusInternalServerError)
 		return store.Application{}, false
 	}
+	p, ok := h.principal(r)
+	if !ok || !p.CanAccessApp(a) {
+		http.NotFound(w, r)
+		return store.Application{}, false
+	}
 	return a, true
 }
 

internal/web/handlers/handlers_backup.go

@@ -13,7 +13,6 @@ import (
 	"github.com/mixeme/selfpost/internal/domain"
 	"github.com/mixeme/selfpost/internal/secretfile"
 	"github.com/mixeme/selfpost/internal/store"
-	"github.com/mixeme/selfpost/internal/web/auth"
 	"github.com/mixeme/selfpost/internal/web/validate"
 )
 
@@ -28,6 +27,9 @@ const maxImportBytes = 1 << 20 // 1 MiB
 // and the domain import are separate actions with different risk, so each gets
 // its own card here rather than sharing a block on the domain list.
 func (h *Handlers) HandleBackupPage(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	h.renderBackupPage(w, r, http.StatusOK, "")
 }
 
@@ -42,14 +44,13 @@ func (h *Handlers) renderBackupPage(w http.ResponseWriter, r *http.Request, stat
 // password), importErr to the import card, so neither message appears under the
 // wrong form.
 func (h *Handlers) renderBackupPageWith(w http.ResponseWriter, r *http.Request, status int, importErr, backupErr string) {
-	h.view.Render(w, status, "backup", map[string]any{
-		"Title":     "SelfPost — backup",
-		"User":      auth.CurrentUser(r),
-		"Active":    "backup",
-		"ImportErr": importErr,
-		"BackupErr": backupErr,
-		"MinPwLen":  validate.MinSecretFilePasswordLen,
-	})
+	data := h.pageBase(r)
+	data["Title"] = "SelfPost — backup"
+	data["Active"] = "backup"
+	data["ImportErr"] = importErr
+	data["BackupErr"] = backupErr
+	data["MinPwLen"] = validate.MinSecretFilePasswordLen
+	h.view.Render(w, status, "backup", data)
 }
 
 // HandleBackup streams a full-server backup as a download (architecture.md §
@@ -61,6 +62,9 @@ func (h *Handlers) renderBackupPageWith(w http.ResponseWriter, r *http.Request,
 // way out, so the file that lands on their disk — wherever it is copied
 // afterwards — is useless without the password.
 func (h *Handlers) HandleBackup(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	password, pwErr := secretFilePassword(r)
 	if pwErr != "" {
 		h.renderBackupPageWith(w, r, http.StatusBadRequest, "", pwErr)
@@ -184,6 +188,9 @@ func (h *Handlers) HandleExportDomain(w http.ResponseWriter, r *http.Request) {
 // re-renders the backup page, where the import form lives, with a friendly
 // message.
 func (h *Handlers) HandleImportDomain(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	r.Body = http.MaxBytesReader(w, r.Body, maxImportBytes)
 	if err := r.ParseMultipartForm(maxImportBytes); err != nil {
 		h.renderBackupPage(w, r, http.StatusBadRequest, "Could not read the uploaded file (too large or not a valid upload).")

internal/web/handlers/handlers_domains.go

@@ -29,27 +29,31 @@ func (h *Handlers) HandleDashboard(w http.ResponseWriter, r *http.Request) {
 }
 
 func (h *Handlers) renderDashboard(w http.ResponseWriter, r *http.Request, status int, formErr, formName string) {
-	domains, err := h.domains.List()
+	p, ok := h.principal(r)
+	if !ok {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+	domains, err := h.assignedDomains(p)
 	if err != nil {
 		logf("panel: dashboard: list domains: %v", err)
 		http.Error(w, "internal error", http.StatusInternalServerError)
 		return
 	}
-	h.view.Render(w, status, "dashboard", map[string]any{
-		"Title":    "SelfPost",
-		"User":     auth.CurrentUser(r),
-		"Active":   "domains",
-		"Domains":  h.domainRows(domains),
-		"Error":    formErr,
-		"FormName": formName,
-		"Flash":    dashboardFlash(r),
-	})
+	data := h.pageBase(r)
+	data["Title"] = "SelfPost"
+	data["Active"] = "domains"
+	data["Domains"] = h.domainRows(domains)
+	data["Error"] = formErr
+	data["FormName"] = formName
+	data["Flash"] = dashboardFlash(r)
+	h.view.Render(w, status, "dashboard", data)
 }
 
 func (h *Handlers) domainRows(domains []store.Domain) []domainRow {
 	profileEmail := ""
-	if admin, err := h.store.GetAdmin(); err == nil {
-		profileEmail = admin.DMARCReportEmail
+	if email, err := h.store.GlobalDMARCReportEmail(); err == nil {
+		profileEmail = email
 	}
 	rows := make([]domainRow, len(domains))
 	var wg sync.WaitGroup
@@ -82,6 +86,9 @@ func dashboardFlash(r *http.Request) string {
 // OpenDKIM reload), and redirects to the domain's page so the DNS record to
 // publish is shown (product.md).
 func (h *Handlers) HandleAddDomain(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	if err := r.ParseForm(); err != nil {
 		h.renderDashboard(w, r, http.StatusBadRequest, "Invalid form submission.", "")
 		return
@@ -109,6 +116,9 @@ func (h *Handlers) HandleAddDomain(w http.ResponseWriter, r *http.Request) {
 
 // HandleDeleteConfirm shows the cascade warning before a domain is removed.
 func (h *Handlers) HandleDeleteConfirm(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	d, ok := h.lookupDomain(w, r)
 	if !ok {
 		return
@@ -118,11 +128,15 @@ func (h *Handlers) HandleDeleteConfirm(w http.ResponseWriter, r *http.Request) {
 		"User":   auth.CurrentUser(r),
 		"Active": "domains",
 		"Domain": d,
+		"IsGlobal": true,
 	})
 }
 
 // HandleDeleteDomain performs the deletion and returns to the domain list.
 func (h *Handlers) HandleDeleteDomain(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	id, ok := parseDomainID(w, r)
 	if !ok {
 		return
@@ -145,6 +159,9 @@ func (h *Handlers) HandleDeleteDomain(w http.ResponseWriter, r *http.Request) {
 // HandleReload re-applies both the OpenDKIM configuration and the Postfix
 // sender map on demand (architecture.md § Panel HTTP surface).
 func (h *Handlers) HandleReload(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	if err := h.domains.Resync(); err != nil {
 		logf("panel: manual reload (opendkim): %v", err)
 		http.Error(w, "reload failed", http.StatusInternalServerError)
@@ -173,6 +190,11 @@ func (h *Handlers) lookupDomain(w http.ResponseWriter, r *http.Request) (store.D
 		http.Error(w, "internal error", http.StatusInternalServerError)
 		return store.Domain{}, false
 	}
+	p, ok := h.principal(r)
+	if !ok || !p.CanAccessDomain(d.ID) {
+		http.NotFound(w, r)
+		return store.Domain{}, false
+	}
 	return d, true
 }
 

internal/web/handlers/handlers_monitor.go

@@ -5,6 +5,7 @@ import (
 	"io/fs"
 	"net/http"
 	"net/url"
+	"sort"
 	"strconv"
 	"time"
 
@@ -38,7 +39,9 @@ func (h *Handlers) HandleDeliveries(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	data["Title"] = "SelfPost — deliveries"
-	data["User"] = auth.CurrentUser(r)
+	for k, v := range h.pageBase(r) {
+		data[k] = v
+	}
 	data["Active"] = "deliveries"
 	h.view.Render(w, http.StatusOK, "deliveries", data)
 }
@@ -85,12 +88,29 @@ func (h *Handlers) HandleDelivery(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "internal error", http.StatusInternalServerError)
 		return
 	}
+	p, ok := h.principal(r)
+	if !ok {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+	if !p.IsGlobal() {
+		allowed, err := h.assignedDomains(p)
+		if err != nil {
+			http.Error(w, "internal error", http.StatusInternalServerError)
+			return
+		}
+		if !domainNameSet(allowed)[row.Domain] {
+			http.NotFound(w, r)
+			return
+		}
+	}
 	row.Subject = mailhdr.DecodeSubject(row.Subject)
 	logRows, logNote := h.deliveryLog(row)
 	h.view.Render(w, http.StatusOK, "delivery", map[string]any{
 		"Title":  "SelfPost — delivery",
 		"User":   auth.CurrentUser(r),
 		"Active": "deliveries",
+		"IsGlobal": p.IsGlobal(),
 		"Row":    row,
 		// The status in the panel's own badge vocabulary, so the headline reads
 		// the same way as every other health signal in the panel.
@@ -269,11 +289,31 @@ func deliveriesBackURL(r *http.Request) string {
 // string, queries the store, and assembles everything the template needs
 // (filter dropdown options plus the current selection, rows, and pagination).
 func (h *Handlers) sendLogData(r *http.Request) (map[string]any, error) {
+	p, ok := h.principal(r)
+	if !ok {
+		return nil, errors.New("no principal")
+	}
 	q := r.URL.Query()
 	filter := store.SendLogFilter{
 		Domain:   q.Get("domain"),
 		AppLogin: q.Get("app"),
 	}
+
+	assigned, err := h.assignedDomains(p)
+	if err != nil {
+		return nil, err
+	}
+	allowedNames := domainNameSet(assigned)
+
+	if !p.IsGlobal() {
+		if filter.Domain != "" && !allowedNames[filter.Domain] {
+			filter.Domain = ""
+		}
+		if filter.Domain == "" && len(assigned) == 1 {
+			filter.Domain = assigned[0].Name
+		}
+	}
+
 	page := parsePage(q.Get("p"))
 
 	total, err := h.store.CountSendLog(filter)
@@ -284,23 +324,33 @@ func (h *Handlers) sendLogData(r *http.Request) (map[string]any, error) {
 	if err != nil {
 		return nil, err
 	}
-	// Decode on the way out as well as on the way in: rows the journal-milter
-	// wrote before it decoded subjects itself still hold the raw header, and
-	// they are the ones an operator is most likely to be looking at.
 	for i := range rows {
 		rows[i].Subject = mailhdr.DecodeSubject(rows[i].Subject)
 	}
-	domains, err := h.store.ListDomains()
-	if err != nil {
-		return nil, err
+
+	domainNames := make([]string, 0, len(assigned))
+	for _, d := range assigned {
+		domainNames = append(domainNames, d.Name)
 	}
-	domainNames := make([]string, len(domains))
-	for i, d := range domains {
-		domainNames[i] = d.Name
+
+	loginSet := make(map[string]bool)
+	for _, d := range assigned {
+		apps, err := h.store.ListApplicationsByDomain(d.ID)
+		if err != nil {
+			return nil, err
+		}
+		for _, a := range apps {
+			loginSet[a.Login] = true
+		}
 	}
-	logins, err := h.store.ListApplicationLogins()
-	if err != nil {
-		return nil, err
+	logins := make([]string, 0, len(loginSet))
+	for login := range loginSet {
+		logins = append(logins, login)
+	}
+	sort.Strings(logins)
+
+	if !p.IsGlobal() && filter.AppLogin != "" && !loginSet[filter.AppLogin] {
+		filter.AppLogin = ""
 	}
 
 	lastPage := 1
@@ -335,18 +385,25 @@ func parsePage(v string) int {
 // HandleMailQueue renders the Mail queue page (architecture.md § Panel HTTP
 // surface).
 func (h *Handlers) HandleMailQueue(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	out, errText := readQueue()
 	h.view.Render(w, http.StatusOK, "mail_queue", map[string]any{
-		"Title":  "SelfPost — mail queue",
-		"User":   auth.CurrentUser(r),
-		"Active": "mail_queue",
-		"Output": out,
-		"Error":  errText,
+		"Title":    "SelfPost — mail queue",
+		"User":     auth.CurrentUser(r),
+		"Active":   "mail_queue",
+		"IsGlobal": true,
+		"Output":   out,
+		"Error":    errText,
 	})
 }
 
 // HandleMailQueueBody serves the HTMX polling fragment for the queue view.
 func (h *Handlers) HandleMailQueueBody(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	out, errText := readQueue()
 	h.view.RenderFragment(w, http.StatusOK, "mail_queue_body", map[string]any{
 		"Output": out,
@@ -369,18 +426,25 @@ func readQueue() (string, string) {
 // HandleSystemLog renders the System log page over mail.log (architecture.md §
 // Panel HTTP surface).
 func (h *Handlers) HandleSystemLog(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	lines, errText := h.readLogTail()
 	h.view.Render(w, http.StatusOK, "system_log", map[string]any{
-		"Title":  "SelfPost — system log",
-		"User":   auth.CurrentUser(r),
-		"Active": "system_log",
-		"Lines":  lines,
-		"Error":  errText,
+		"Title":    "SelfPost — system log",
+		"User":     auth.CurrentUser(r),
+		"Active":   "system_log",
+		"IsGlobal": true,
+		"Lines":    lines,
+		"Error":    errText,
 	})
 }
 
 // HandleSystemLogBody serves the HTMX polling fragment for the log-tail view.
 func (h *Handlers) HandleSystemLogBody(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	lines, errText := h.readLogTail()
 	h.view.RenderFragment(w, http.StatusOK, "system_log_body", map[string]any{
 		"Lines": lines,

internal/web/handlers/handlers_monitor_test.go

@@ -10,6 +10,7 @@ import (
 	"testing"
 
 	"github.com/mixeme/selfpost/internal/store"
+	"github.com/mixeme/selfpost/internal/web/auth"
 )
 
 // After log rotation renames mail.log away, Postfix takes about a second to
@@ -252,6 +253,11 @@ func getBody(t *testing.T, h http.HandlerFunc, target string) string {
 	t.Helper()
 	rec := httptest.NewRecorder()
 	req := httptest.NewRequest(http.MethodGet, target, nil)
+	req = auth.RequestWithPrincipal(req, auth.Principal{
+		ID:       1,
+		Username: "admin",
+		Role:     auth.RoleGlobal,
+	})
 	if rest, ok := strings.CutPrefix(req.URL.Path, "/deliveries/"); ok && rest != "rows" {
 		req.SetPathValue("id", rest)
 	}

internal/web/handlers/handlers_status.go

@@ -9,23 +9,33 @@ import (
 )
 
 func (h *Handlers) HandleStatus(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	data := h.statusBody()
 	srv := h.dns.Server(h.cfg.Hostname, false)
 
 	data["Title"] = "SelfPost — status"
 	data["User"] = auth.CurrentUser(r)
 	data["Active"] = "status"
+	data["IsGlobal"] = true
 	data["Flash"] = statusFlash(r)
 	data["Hostname"] = h.cfg.Hostname
 	data["PTR"] = srv.PTR
 	h.view.Render(w, http.StatusOK, "status", data)
 }
 
-func (h *Handlers) HandleStatusFragment(w http.ResponseWriter, _ *http.Request) {
+func (h *Handlers) HandleStatusFragment(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	h.view.RenderFragment(w, http.StatusOK, "status_body", h.statusBody())
 }
 
 func (h *Handlers) HandleStatusRecheck(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
 	h.dns.Server(h.cfg.Hostname, true)
 	http.Redirect(w, r, "/status?rechecked=1", http.StatusSeeOther)
 }

internal/web/handlers/handlers_users.go

@@ -0,0 +1,328 @@
+package handlers
+
+import (
+	"errors"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/mixeme/selfpost/internal/store"
+	"github.com/mixeme/selfpost/internal/web/validate"
+	"golang.org/x/crypto/bcrypt"
+)
+
+type userFormView struct {
+	FormErr      string
+	FormUsername string
+	FormRole     string
+	FormDomains  map[int64]bool
+	FormPassword string
+}
+
+// HandleUsers lists panel users (global only).
+func (h *Handlers) HandleUsers(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
+	rows, err := h.store.ListUserRows()
+	if err != nil {
+		logf("panel: list users: %v", err)
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+	data := h.pageBase(r)
+	data["Title"] = "SelfPost — users"
+	data["Active"] = "users"
+	data["Users"] = rows
+	data["Flash"] = usersFlash(r)
+	h.view.Render(w, http.StatusOK, "users", data)
+}
+
+func usersFlash(r *http.Request) string {
+	switch r.URL.Query().Get("done") {
+	case "created":
+		return "User created."
+	case "updated":
+		return "User updated."
+	case "deleted":
+		return "User deleted."
+	default:
+		return ""
+	}
+}
+
+// HandleUserNew creates a panel user (global only).
+func (h *Handlers) HandleUserNew(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
+	switch r.Method {
+	case http.MethodGet:
+		h.renderUserForm(w, r, http.StatusOK, 0, userFormView{FormRole: string(store.RoleDomainAdmin)})
+	case http.MethodPost:
+		h.submitUserCreate(w, r)
+	default:
+		w.Header().Set("Allow", "GET, POST")
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+
+// HandleUserEdit edits or deletes a panel user (global only).
+func (h *Handlers) HandleUserEdit(w http.ResponseWriter, r *http.Request) {
+	if _, ok := h.requireGlobal(w, r); !ok {
+		return
+	}
+	uid, ok := parseUserID(w, r)
+	if !ok {
+		return
+	}
+	u, err := h.store.GetUser(uid)
+	if err != nil {
+		if errors.Is(err, store.ErrUserNotFound) {
+			http.NotFound(w, r)
+			return
+		}
+		logf("panel: get user %d: %v", uid, err)
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+	switch r.Method {
+	case http.MethodGet:
+		selected := make(map[int64]bool, len(u.DomainIDs))
+		for _, id := range u.DomainIDs {
+			selected[id] = true
+		}
+		h.renderUserForm(w, r, http.StatusOK, u.ID, userFormView{
+			FormUsername: u.Username,
+			FormRole:     string(u.Role),
+			FormDomains:  selected,
+		})
+	case http.MethodPost:
+		if err := r.ParseForm(); err != nil {
+			h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "Invalid form submission.", FormUsername: u.Username, FormRole: string(u.Role)})
+			return
+		}
+		if r.PostFormValue("action") == "delete" {
+			h.submitUserDelete(w, r, u)
+			return
+		}
+		h.submitUserUpdate(w, r, u)
+	default:
+		w.Header().Set("Allow", "GET, POST")
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+
+func (h *Handlers) renderUserForm(w http.ResponseWriter, r *http.Request, status int, userID int64, view userFormView) {
+	domains, err := h.store.ListDomains()
+	if err != nil {
+		logf("panel: user form: list domains: %v", err)
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+	data := h.pageBase(r)
+	data["Title"] = "SelfPost — user"
+	data["Active"] = "users"
+	data["UserID"] = userID
+	data["Domains"] = domains
+	data["Error"] = view.FormErr
+	data["FormUsername"] = view.FormUsername
+	data["FormRole"] = view.FormRole
+	data["FormDomains"] = view.FormDomains
+	data["FormPassword"] = view.FormPassword
+	data["IsEdit"] = userID != 0
+	h.view.Render(w, status, "user_form", data)
+}
+
+func (h *Handlers) submitUserCreate(w http.ResponseWriter, r *http.Request) {
+	if err := r.ParseForm(); err != nil {
+		h.renderUserForm(w, r, http.StatusBadRequest, 0, userFormView{FormErr: "Invalid form submission."})
+		return
+	}
+	username := strings.TrimSpace(r.PostFormValue("username"))
+	password := r.PostFormValue("password")
+	role := store.Role(r.PostFormValue("role"))
+	domainIDs := parseDomainIDs(r)
+
+	if err := validate.Username(username); err != nil {
+		h.renderUserForm(w, r, http.StatusBadRequest, 0, userFormView{FormErr: err.Error(), FormUsername: username, FormRole: string(role), FormDomains: domainIDSetFromForm(r)})
+		return
+	}
+	if err := validate.AdminPassword(password); err != nil {
+		h.renderUserForm(w, r, http.StatusBadRequest, 0, userFormView{FormErr: err.Error(), FormUsername: username, FormRole: string(role), FormDomains: domainIDSetFromForm(r)})
+		return
+	}
+	if role != store.RoleGlobal && role != store.RoleDomainAdmin {
+		h.renderUserForm(w, r, http.StatusBadRequest, 0, userFormView{FormErr: "Choose a valid role.", FormUsername: username, FormRole: string(role), FormDomains: domainIDSetFromForm(r)})
+		return
+	}
+	if role == store.RoleDomainAdmin && len(domainIDs) == 0 {
+		h.renderUserForm(w, r, http.StatusBadRequest, 0, userFormView{FormErr: "Select at least one domain for a domain administrator.", FormUsername: username, FormRole: string(role), FormDomains: domainIDSetFromForm(r)})
+		return
+	}
+
+	hash, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
+	if err != nil {
+		logf("panel: create user hash: %v", err)
+		h.renderUserForm(w, r, http.StatusInternalServerError, 0, userFormView{FormErr: "Internal error. Please try again."})
+		return
+	}
+	if _, err := h.store.CreateUser(username, string(hash), role, domainIDs); err != nil {
+		if errors.Is(err, store.ErrUserExists) {
+			h.renderUserForm(w, r, http.StatusConflict, 0, userFormView{FormErr: "That username is already in use.", FormUsername: username, FormRole: string(role), FormDomains: domainIDSetFromForm(r)})
+			return
+		}
+		logf("panel: create user: %v", err)
+		h.renderUserForm(w, r, http.StatusInternalServerError, 0, userFormView{FormErr: "Could not create user. Please check the logs."})
+		return
+	}
+	http.Redirect(w, r, "/users?done=created", http.StatusSeeOther)
+}
+
+func (h *Handlers) submitUserUpdate(w http.ResponseWriter, r *http.Request, u store.User) {
+	if err := r.ParseForm(); err != nil {
+		h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "Invalid form submission.", FormUsername: u.Username, FormRole: string(u.Role)})
+		return
+	}
+	p, ok := h.principal(r)
+	if !ok {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+
+	username := strings.TrimSpace(r.PostFormValue("username"))
+	password := r.PostFormValue("password")
+	role := store.Role(r.PostFormValue("role"))
+	domainIDs := parseDomainIDs(r)
+	selected := domainIDSetFromForm(r)
+
+	if username == "" {
+		username = u.Username
+	}
+	if err := validate.Username(username); err != nil {
+		h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: err.Error(), FormUsername: username, FormRole: string(role), FormDomains: selected})
+		return
+	}
+	if role != store.RoleGlobal && role != store.RoleDomainAdmin {
+		h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "Choose a valid role.", FormUsername: username, FormRole: string(role), FormDomains: selected})
+		return
+	}
+	if role == store.RoleDomainAdmin && len(domainIDs) == 0 {
+		h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "Select at least one domain for a domain administrator.", FormUsername: username, FormRole: string(role), FormDomains: selected})
+		return
+	}
+
+	if u.Role == store.RoleGlobal && role == store.RoleDomainAdmin {
+		n, err := h.store.CountGlobalUsers()
+		if err != nil || n <= 1 {
+			h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "Cannot demote the last global administrator.", FormUsername: username, FormRole: string(u.Role), FormDomains: selected})
+			return
+		}
+	}
+
+	if u.ID == p.ID && u.Role == store.RoleGlobal && role == store.RoleDomainAdmin {
+		n, err := h.store.CountGlobalUsers()
+		if err != nil || n <= 1 {
+			h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "You cannot demote yourself without another global administrator.", FormUsername: username, FormRole: string(u.Role), FormDomains: selected})
+			return
+		}
+	}
+
+	hash := u.PasswordHash
+	if password != "" {
+		if err := validate.AdminPassword(password); err != nil {
+			h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: err.Error(), FormUsername: username, FormRole: string(role), FormDomains: selected})
+			return
+		}
+		newHash, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
+		if err != nil {
+			logf("panel: update user hash: %v", err)
+			h.renderUserForm(w, r, http.StatusInternalServerError, u.ID, userFormView{FormErr: "Internal error. Please try again.", FormUsername: username, FormRole: string(role), FormDomains: selected})
+			return
+		}
+		hash = string(newHash)
+	}
+
+	if err := h.store.UpdateUser(u.ID, username, hash, u.DMARCReportEmail); err != nil {
+		if errors.Is(err, store.ErrUserExists) {
+			h.renderUserForm(w, r, http.StatusConflict, u.ID, userFormView{FormErr: "That username is already in use.", FormUsername: username, FormRole: string(role), FormDomains: selected})
+			return
+		}
+		logf("panel: update user: %v", err)
+		h.renderUserForm(w, r, http.StatusInternalServerError, u.ID, userFormView{FormErr: "Could not save user. Please check the logs.", FormUsername: username, FormRole: string(role), FormDomains: selected})
+		return
+	}
+
+	if role != u.Role {
+		if err := h.store.SetUserRole(u.ID, role); err != nil {
+			logf("panel: set user role: %v", err)
+			h.renderUserForm(w, r, http.StatusInternalServerError, u.ID, userFormView{FormErr: "Could not update role.", FormUsername: username, FormRole: string(role), FormDomains: selected})
+			return
+		}
+		if role == store.RoleGlobal {
+			if err := h.store.ClearUserDomains(u.ID); err != nil {
+				logf("panel: clear user domains: %v", err)
+			}
+		}
+	}
+
+	if role == store.RoleDomainAdmin {
+		if err := h.store.SetUserDomains(u.ID, domainIDs); err != nil {
+			logf("panel: set user domains: %v", err)
+			h.renderUserForm(w, r, http.StatusInternalServerError, u.ID, userFormView{FormErr: "Could not save domain assignments.", FormUsername: username, FormRole: string(role), FormDomains: selected})
+			return
+		}
+	}
+
+	http.Redirect(w, r, "/users?done=updated", http.StatusSeeOther)
+}
+
+func (h *Handlers) submitUserDelete(w http.ResponseWriter, r *http.Request, u store.User) {
+	p, ok := h.principal(r)
+	if !ok {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+	if u.ID == p.ID {
+		h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "You cannot delete your own account while signed in.", FormUsername: u.Username, FormRole: string(u.Role)})
+		return
+	}
+	if err := h.store.DeleteUser(u.ID); err != nil {
+		if errors.Is(err, store.ErrLastGlobal) {
+			h.renderUserForm(w, r, http.StatusBadRequest, u.ID, userFormView{FormErr: "Cannot delete the last global administrator.", FormUsername: u.Username, FormRole: string(u.Role)})
+			return
+		}
+		logf("panel: delete user %d: %v", u.ID, err)
+		h.renderUserForm(w, r, http.StatusInternalServerError, u.ID, userFormView{FormErr: "Could not delete user.", FormUsername: u.Username, FormRole: string(u.Role)})
+		return
+	}
+	http.Redirect(w, r, "/users?done=deleted", http.StatusSeeOther)
+}
+
+func parseUserID(w http.ResponseWriter, r *http.Request) (int64, bool) {
+	id, err := strconv.ParseInt(r.PathValue("uid"), 10, 64)
+	if err != nil || id <= 0 {
+		http.NotFound(w, r)
+		return 0, false
+	}
+	return id, true
+}
+
+func parseDomainIDs(r *http.Request) []int64 {
+	var ids []int64
+	for _, v := range r.PostForm["domain_ids"] {
+		id, err := strconv.ParseInt(v, 10, 64)
+		if err == nil && id > 0 {
+			ids = append(ids, id)
+		}
+	}
+	return ids
+}
+
+func domainIDSetFromForm(r *http.Request) map[int64]bool {
+	m := make(map[int64]bool)
+	for _, id := range parseDomainIDs(r) {
+		m[id] = true
+	}
+	return m
+}

internal/web/view/templates/account.html

@@ -23,6 +23,7 @@
     <label for="new_password_confirm">Confirm new password</label>
     <input id="new_password_confirm" name="new_password_confirm" type="password" autocomplete="new-password">
 
+    {{if .ShowDMARC}}
     <h3>DMARC aggregate reports</h3>
     <p class="muted">Optional default <code>rua=</code> address for every sending
     domain (can be overridden per domain). Use a mailbox on a domain that
@@ -58,11 +59,12 @@
 {{end}}</span>{{end}}
     {{end}}
     {{end}}
+    {{end}}
 
     <button type="submit">Save changes</button>
   </form>
   <p class="muted">Leave both new-password fields empty to change the username
-  or DMARC address only. Changing the password signs out every other session;
+  {{if .ShowDMARC}}or DMARC address {{end}}only. Changing the password signs out every other session;
   this one stays signed in.</p>
 </div>
 {{end}}

internal/web/view/templates/dashboard.html

@@ -3,6 +3,7 @@
 
 {{if .Flash}}<div class="flash">{{.Flash}}</div>{{end}}
 
+{{if .IsGlobal}}
 <div class="card">
   <h2>Add a sending domain</h2>
   <form method="post" action="/domains">
@@ -16,6 +17,7 @@
   <p class="muted">A DKIM key is generated for the domain; you then publish the
   shown DNS record. Adding a domain does not create an application.</p>
 </div>
+{{end}}
 
 <div class="card">
   <h2>Domains</h2>
@@ -31,7 +33,7 @@
         <td><a class="st st-{{.DNS}}" href="/domains/{{.ID}}#dns-status">{{.DNS}}</a></td>
         <td class="muted">{{.DKIMSelector}}</td>
         <td>{{.AppCount}}</td>
-        <td class="actions"><a class="danger" href="/domains/{{.ID}}/delete">Delete</a></td>
+        {{if $.IsGlobal}}<td class="actions"><a class="danger" href="/domains/{{.ID}}/delete">Delete</a></td>{{else}}<td></td>{{end}}
       </tr>
       {{end}}
     </tbody>

internal/web/view/templates/layout.html

@@ -64,14 +64,19 @@
        the column: the mark, the panel's pages, the current page's own sections,
        and the session last. The mark goes to /status, the page the panel opens
        on — named outright rather than as "/", which is only a redirect to it. */}}
-  <a class="brand" href="/status"><img src="/static/logo-compact.svg" width="220" height="100" alt="SelfPost"></a>
+  <a class="brand" href="{{if .IsGlobal}}/status{{else}}/domains{{end}}"><img src="/static/logo-compact.svg" width="220" height="100" alt="SelfPost"></a>
   <div class="links">
+    {{if .IsGlobal}}
     {{if eq .Active "status"}}<span aria-current="page">{{template "icon-status"}}Status</span>{{else}}<a href="/status">{{template "icon-status"}}Status</a>{{end}}
+    {{end}}
     {{if eq .Active "domains"}}<span aria-current="page">{{template "icon-domains"}}Domains</span>{{else}}<a href="/domains">{{template "icon-domains"}}Domains</a>{{end}}
     {{if eq .Active "deliveries"}}<span aria-current="page">{{template "icon-deliveries"}}Deliveries</span>{{else}}<a href="/deliveries">{{template "icon-deliveries"}}Deliveries</a>{{end}}
+    {{if .IsGlobal}}
     {{if eq .Active "mail_queue"}}<span aria-current="page">{{template "icon-mail-queue"}}Mail queue</span>{{else}}<a href="/mail-queue">{{template "icon-mail-queue"}}Mail queue</a>{{end}}
     {{if eq .Active "system_log"}}<span aria-current="page">{{template "icon-system-log"}}System log</span>{{else}}<a href="/system-log">{{template "icon-system-log"}}System log</a>{{end}}
     {{if eq .Active "backup"}}<span aria-current="page">{{template "icon-backup"}}Backup</span>{{else}}<a href="/backup">{{template "icon-backup"}}Backup</a>{{end}}
+    {{if eq .Active "users"}}<span aria-current="page">{{template "icon-account"}}Users</span>{{else}}<a href="/users">{{template "icon-account"}}Users</a>{{end}}
+    {{end}}
   </div>
   {{template "sections" .}}
   <div class="session">

internal/web/view/templates/user_form.html

@@ -0,0 +1,38 @@
+{{define "content"}}
+<h1>{{if .IsEdit}}Edit user{{else}}Create user{{end}}</h1>
+
+<div class="card narrow">
+  {{if .Error}}<p class="error">{{.Error}}</p>{{end}}
+  <form method="post" action="{{if .IsEdit}}/users/{{.UserID}}{{else}}/users/new{{end}}">
+    <label for="username">Username</label>
+    <input id="username" name="username" autocomplete="username"
+           autocapitalize="none" spellcheck="false" value="{{.FormUsername}}" required>
+
+    <label for="password">Password{{if .IsEdit}} (leave empty to keep){{end}}</label>
+    <input id="password" name="password" type="password" autocomplete="new-password" {{if not .IsEdit}}required{{end}}>
+
+    <label for="role">Role</label>
+    <select id="role" name="role">
+      <option value="domain_admin" {{if eq .FormRole "domain_admin"}}selected{{end}}>Domain administrator</option>
+      <option value="global" {{if eq .FormRole "global"}}selected{{end}}>Global administrator</option>
+    </select>
+
+    <fieldset id="domain-pick">
+      <legend>Assigned domains</legend>
+      <p class="muted">Required for domain administrators.</p>
+      {{range .Domains}}
+      <label class="checkbox">
+        <input type="checkbox" name="domain_ids" value="{{.ID}}" {{if index $.FormDomains .ID}}checked{{end}}>
+        {{.Name}}
+      </label>
+      {{end}}
+    </fieldset>
+
+    <button type="submit">{{if .IsEdit}}Save{{else}}Create{{end}}</button>
+    {{if .IsEdit}}
+    <button type="submit" name="action" value="delete" class="danger">Delete user</button>
+    {{end}}
+  </form>
+  <p class="muted"><a href="/users">Back to users</a></p>
+</div>
+{{end}}

internal/web/view/templates/users.html

@@ -0,0 +1,28 @@
+{{define "content"}}
+<h1>Panel users</h1>
+
+{{if .Flash}}<div class="flash">{{.Flash}}</div>{{end}}
+
+<div class="card">
+  <p><a href="/users/new">Create user</a></p>
+  {{if .Users}}
+  <table>
+    <thead>
+      <tr><th>Username</th><th>Role</th><th>Domains</th><th></th></tr>
+    </thead>
+    <tbody>
+      {{range .Users}}
+      <tr>
+        <td>{{.User.Username}}</td>
+        <td>{{if eq .User.Role "global"}}Global{{else}}Domain admin{{end}}</td>
+        <td class="muted">{{if eq .User.Role "global"}}All{{else}}{{range $i, $n := .DomainNames}}{{if $i}}, {{end}}{{$n}}{{end}}{{end}}</td>
+        <td class="actions"><a href="/users/{{.User.ID}}">Edit</a></td>
+      </tr>
+      {{end}}
+    </tbody>
+  </table>
+  {{else}}
+  <p class="muted">No panel users besides the global administrator yet.</p>
+  {{end}}
+</div>
+{{end}}

internal/web/view/templates_test.go

@@ -207,8 +207,9 @@ func TestNavMarksActivePage(t *testing.T) {
 	}
 	var buf bytes.Buffer
 	err = engine.Page("dashboard").ExecuteTemplate(&buf, "nav", map[string]any{
-		"User":   "admin",
-		"Active": "mail_queue",
+		"User":     "admin",
+		"Active":   "mail_queue",
+		"IsGlobal": true,
 	})
 	if err != nil {
 		t.Fatalf("execute nav: %v", err)
@@ -234,8 +235,9 @@ func TestNavLeadsWithStatusAndPointsDomainsAtItsOwnPath(t *testing.T) {
 	}
 	var buf bytes.Buffer
 	if err := engine.Page("status").ExecuteTemplate(&buf, "nav", map[string]any{
-		"User":   "admin",
-		"Active": "status",
+		"User":     "admin",
+		"Active":   "status",
+		"IsGlobal": true,
 	}); err != nil {
 		t.Fatalf("execute nav: %v", err)
 	}

internal/web/view/view.go

@@ -35,6 +35,8 @@ var pageFiles = map[string][]string{
 	"login":         {"templates/login.html"},
 	"dashboard":     {"templates/dashboard.html"},
 	"account":       {"templates/account.html"},
+	"users":         {"templates/users.html"},
+	"user_form":     {"templates/user_form.html"},
 	"backup":        {"templates/backup.html", "templates/encrypt_fields.html"},
 	"domain_detail": {"templates/domain_detail.html", "templates/encrypt_fields.html"},
 	"domain_delete": {"templates/domain_delete.html"},

internal/web/web.go

@@ -129,7 +129,7 @@ func (s *Server) Handler() http.Handler {
 	mux.HandleFunc("/logout", s.auth.HandleLogout)
 
 	authed := http.NewServeMux()
-	authed.HandleFunc("GET /{$}", redirectToStatus)
+	authed.HandleFunc("GET /{$}", redirectHome)
 	authed.HandleFunc("GET /status", h.HandleStatus)
 	authed.HandleFunc("GET /status/fragment", h.HandleStatusFragment)
 	authed.HandleFunc("POST /status/recheck", h.HandleStatusRecheck)
@@ -153,6 +153,12 @@ func (s *Server) Handler() http.Handler {
 
 	authed.HandleFunc("/account", h.HandleAccount)
 
+	authed.HandleFunc("GET /users", h.HandleUsers)
+	authed.HandleFunc("GET /users/new", h.HandleUserNew)
+	authed.HandleFunc("POST /users/new", h.HandleUserNew)
+	authed.HandleFunc("GET /users/{uid}", h.HandleUserEdit)
+	authed.HandleFunc("POST /users/{uid}", h.HandleUserEdit)
+
 	authed.HandleFunc("GET /backup", h.HandleBackupPage)
 	authed.HandleFunc("POST /backup", h.HandleBackup)
 
@@ -168,7 +174,12 @@ func (s *Server) Handler() http.Handler {
 	return s.secure(mux)
 }
 
-func redirectToStatus(w http.ResponseWriter, r *http.Request) {
+func redirectHome(w http.ResponseWriter, r *http.Request) {
+	p, ok := auth.PrincipalFromRequest(r)
+	if ok && !p.IsGlobal() {
+		http.Redirect(w, r, "/domains", http.StatusSeeOther)
+		return
+	}
 	http.Redirect(w, r, "/status", http.StatusSeeOther)
 }