1 files changed, 193 insertions, 0 deletions
diff --git a/auth_files.go b/auth_files.go
new file mode 100644
index 0000000..22b1e60
--- /dev/null
+++ b/auth_files.go
@@ -0,0 +1,193 @@
+package proxy
+
+import (
+	"net"
+	"os"
+	"time"
+)
+
+type authFiles struct{}
+
+// Exists reports whether a user is registered.
+func (a authFiles) Exists(name string) bool {
+	os.Mkdir(Path("auth"), 0700)
+
+	_, err := os.Stat(Path("auth/", name))
+	return err == nil
+}
+
+// Passwd returns the SRP salt and verifier of a user or an error.
+func (a authFiles) Passwd(name string) (salt, verifier []byte, err error) {
+	os.Mkdir(Path("auth"), 0700)
+
+	salt, err = os.ReadFile(Path("auth/", name, "/salt"))
+	if err != nil {
+		return
+	}
+
+	verifier, err = os.ReadFile(Path("auth/", name, "/verifier"))
+	if err != nil {
+		return
+	}
+
+	a.updateTimestamp(name)
+	return
+}
+
+// SetPasswd creates a password entry if necessary
+// and sets the password of a user.
+func (a authFiles) SetPasswd(name string, salt, verifier []byte) error {
+	os.Mkdir(Path("auth"), 0700)
+	os.Mkdir(Path("auth/", name), 0700)
+
+	if err := os.WriteFile(Path("auth/", name, "/salt"), salt, 0600); err != nil {
+		return err
+	}
+
+	if err := os.WriteFile(Path("auth/", name, "/verifier"), verifier, 0600); err != nil {
+		return err
+	}
+
+	a.updateTimestamp(name)
+	return nil
+}
+
+// Timestamp returns the last time an authentication entry was accessed
+// or an error.
+func (a authFiles) Timestamp(name string) (time.Time, error) {
+	os.Mkdir(Path("auth"), 0700)
+
+	info, err := os.Stat(Path("auth/", name, "/timestamp"))
+	if err != nil {
+		return time.Time{}, err
+	}
+
+	return info.ModTime(), nil
+}
+
+// Import deletes all users and adds the passed users.
+func (a authFiles) Import(in []user) {
+	os.Mkdir(Path("auth"), 0700)
+
+	for _, u := range in {
+		a.SetPasswd(u.name, u.salt, u.verifier)
+		os.Chtimes(Path("auth/", u.name, "/timestamp"), u.timestamp, u.timestamp)
+	}
+}
+
+// Export returns data that can be processed by Import
+// or an error.
+func (a authFiles) Export() ([]user, error) {
+	dir, err := os.ReadDir(Path("auth"))
+	if err != nil {
+		return nil, err
+	}
+
+	var out []user
+	for _, f := range dir {
+		u := user{name: f.Name()}
+
+		u.timestamp, err = a.Timestamp(u.name)
+		if err != nil {
+			return nil, err
+		}
+
+		u.salt, u.verifier, err = a.Passwd(u.name)
+		if err != nil {
+			return nil, err
+		}
+
+		out = append(out, u)
+	}
+
+	return out, nil
+}
+
+// Ban adds a ban entry for a network address and an associated name.
+func (a authFiles) Ban(addr, name string) error {
+	os.Mkdir(Path("ban"), 0700)
+	return os.WriteFile(Path("ban/", addr), []byte(name), 0600)
+}
+
+// Unban deletes a ban entry. It accepts both network addresses
+// and player names.
+func (a authFiles) Unban(id string) error {
+	os.Mkdir(Path("ban"), 0700)
+
+	if err := os.Remove(Path("ban/", id)); err != nil {
+		if os.IsNotExist(err) {
+			dir, err := os.ReadDir(Path("ban"))
+			if err != nil {
+				return err
+			}
+
+			for _, f := range dir {
+				name, err := os.ReadFile(Path("ban/", f.Name()))
+				if err != nil {
+					return err
+				}
+
+				if string(name) == id {
+					return os.Remove(Path("ban/", f.Name()))
+					break
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+// Banned reports whether a network address is banned.
+func (a authFiles) Banned(addr *net.UDPAddr) bool {
+	os.Mkdir(Path("ban"), 0700)
+
+	_, err := os.Stat(Path("ban/", addr.IP.String()))
+	if os.IsNotExist(err) {
+		return false
+	}
+
+	return true
+}
+
+// ImportBans deletes all ban entries and adds the passed entries.
+func (a authFiles) ImportBans(in []ban) {
+	os.Mkdir(Path("ban"), 0700)
+
+	for _, b := range in {
+		a.Ban(b.addr, b.name)
+	}
+}
+
+// ExportBans returns data that can be processed by ImportBans
+// or an error,
+func (a authFiles) ExportBans() ([]ban, error) {
+	os.Mkdir(Path("ban"), 0700)
+
+	dir, err := os.ReadDir(Path("ban"))
+	if err != nil {
+		return nil, err
+	}
+
+	var out []ban
+	for _, f := range dir {
+		b := ban{addr: f.Name()}
+
+		name, err := os.ReadFile(Path("ban/", f.Name()))
+		if err != nil {
+			return nil, err
+		}
+
+		b.name = string(name)
+		out = append(out, b)
+	}
+
+	return out, nil
+}
+
+func (a authFiles) updateTimestamp(name string) {
+	os.Mkdir(Path("auth"), 0700)
+
+	t := time.Now().Local()
+	os.Chtimes(Path("auth/", name, "/timestamp"), t, t)
+}