feat: add web ui and dynamic private users

chfs-ng/internal/auth/users.go

@@ -0,0 +1,119 @@
+package auth
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+	"sync"
+)
+
+type UserStore struct {
+	Path string
+	Mu   sync.Mutex
+}
+
+type userRecord struct {
+	Username string `json:"username"`
+	Password string `json:"passwordHash"`
+	Home     string `json:"home"`
+}
+
+var validUsername = regexp.MustCompile("^[A-Za-z0-9][A-Za-z0-9._-]{0,31}$")
+
+func ValidateUsername(username string) error {
+	if !validUsername.MatchString(username) {
+		return fmt.Errorf("invalid username")
+	}
+	return nil
+}
+
+func (u *UserStore) Load(m *Manager, homeRoot string) error {
+	if u.Path == "" {
+		return nil
+	}
+	data, err := os.ReadFile(u.Path)
+	if os.IsNotExist(err) {
+		return nil
+	}
+	if err != nil {
+		return err
+	}
+	var records []userRecord
+	if err := json.Unmarshal(data, &records); err != nil {
+		return fmt.Errorf("invalid user store: %w", err)
+	}
+	for _, rec := range records {
+		if err := ValidateUsername(rec.Username); err != nil || rec.Password == "" {
+			continue
+		}
+		if _, exists := m.Accounts[rec.Username]; exists {
+			continue
+		}
+		home := filepath.ToSlash(strings.Trim(strings.TrimSpace(rec.Home), "/"))
+		if home == "" {
+			home = filepath.ToSlash(filepath.Join(homeRoot, rec.Username))
+		}
+		a := &Account{Username: rec.Username, PasswordHash: rec.Password, Mask: None, Home: home}
+		a.Rules = append(a.Rules, PathRule{Dir: home, Mask: Read | Write | Delete})
+		m.Accounts[rec.Username] = a
+	}
+	return nil
+}
+
+func (u *UserStore) Save(m *Manager) error {
+	if u.Path == "" {
+		return nil
+	}
+	u.Mu.Lock()
+	defer u.Mu.Unlock()
+	records := make([]userRecord, 0)
+	for _, a := range m.Accounts {
+		if a.PasswordHash == "" || a.Home == "" || a.Admin {
+			continue
+		}
+		records = append(records, userRecord{Username: a.Username, Password: a.PasswordHash, Home: a.Home})
+	}
+	data, err := json.MarshalIndent(records, "", "  ")
+	if err != nil {
+		return err
+	}
+	if dir := filepath.Dir(u.Path); dir != "." {
+		if err := os.MkdirAll(dir, 0700); err != nil {
+			return err
+		}
+	}
+	tmp := u.Path + ".tmp"
+	if err := os.WriteFile(tmp, data, 0600); err != nil {
+		return err
+	}
+	return os.Rename(tmp, u.Path)
+}
+
+func (u *UserStore) Add(m *Manager, username, password, home string) (*Account, error) {
+	if err := ValidateUsername(username); err != nil {
+		return nil, err
+	}
+	if strings.TrimSpace(password) == "" {
+		return nil, fmt.Errorf("password required")
+	}
+	if _, ok := m.Accounts[username]; ok {
+		return nil, fmt.Errorf("user already exists")
+	}
+	home = strings.Trim(home, "/")
+	a := &Account{Username: username, PasswordHash: PasswordHash(password), Mask: None, Home: home}
+	a.Rules = append(a.Rules, PathRule{Dir: home, Mask: Read | Write | Delete})
+	m.Accounts[username] = a
+	return a, u.Save(m)
+}
+
+func (u *UserStore) Delete(m *Manager, username string) error {
+	a, ok := m.Accounts[username]
+	if !ok || a.Admin || a.PasswordHash == "" {
+		return fmt.Errorf("managed user not found")
+	}
+	delete(m.Accounts, username)
+	return u.Save(m)
+}