conf: introduce configuration management

1 files changed, 199 insertions, 0 deletions

diff --git a/conf/store.go b/conf/store.go
new file mode 100644
index 00000000..7c110865
--- /dev/null
+++ b/conf/store.go
@@ -0,0 +1,199 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2019 WireGuard LLC. All Rights Reserved.
+ */
+
+package conf
+
+import (
+	"errors"
+	"golang.zx2c4.com/wireguard/windows/conf/dpapi"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+const configFileSuffix = ".conf.dpapi"
+const configFileUnencryptedSuffix = ".conf"
+
+func ListConfigNames() ([]string, error) {
+	configFileDir, err := resolveConfigFileDir()
+	if err != nil {
+		return nil, err
+	}
+	files, err := ioutil.ReadDir(configFileDir)
+	if err != nil {
+		return nil, err
+	}
+	configs := make([]string, len(files))
+	i := 0
+	for _, file := range files {
+		name := filepath.Base(file.Name())
+		if len(name) <= len(configFileSuffix) || !strings.HasSuffix(name, configFileSuffix) {
+			continue
+		}
+		if !file.Mode().IsRegular() || file.Mode().Perm()&0444 == 0 {
+			continue
+		}
+		configs[i] = strings.TrimSuffix(name, configFileSuffix)
+		i++
+	}
+	return configs[:i], nil
+}
+
+func MigrateUnencryptedConfigs() (int, []error) {
+	configFileDir, err := resolveConfigFileDir()
+	if err != nil {
+		return 0, []error{err}
+	}
+	files, err := ioutil.ReadDir(configFileDir)
+	if err != nil {
+		return 0, []error{err}
+	}
+	errs := make([]error, len(files))
+	i := 0
+	e := 0
+	for _, file := range files {
+		path := filepath.Join(configFileDir, file.Name())
+		name := filepath.Base(file.Name())
+		if len(name) <= len(configFileUnencryptedSuffix) || !strings.HasSuffix(name, configFileUnencryptedSuffix) {
+			continue
+		}
+		if !file.Mode().IsRegular() || file.Mode().Perm()&0444 == 0 {
+			continue
+		}
+
+		// We don't use ioutil's ReadFile, because we actually want RDWR, so that we can take advantage
+		// of Windows file locking for ensuring the file is finished being written.
+		f, err := os.OpenFile(path, os.O_RDWR, 0)
+		if err != nil {
+			errs[e] = err
+			e++
+			continue
+		}
+		bytes, err := ioutil.ReadAll(f)
+		f.Close()
+		if err != nil {
+			errs[e] = err
+			e++
+			continue
+		}
+		_, err = FromWgQuick(string(bytes), "input")
+		if err != nil {
+			errs[e] = err
+			e++
+			continue
+		}
+
+		bytes, err = dpapi.Encrypt(bytes, strings.TrimSuffix(name, configFileUnencryptedSuffix))
+		if err != nil {
+			errs[e] = err
+			e++
+			continue
+		}
+		dstFile := strings.TrimSuffix(path, configFileUnencryptedSuffix) + configFileSuffix
+		if _, err = os.Stat(dstFile); err != nil && !os.IsNotExist(err) {
+			errs[e] = errors.New("Unable to migrate to " + dstFile + " as it already exists")
+			e++
+			continue
+		}
+		err = ioutil.WriteFile(dstFile, bytes, 0600)
+		if err != nil {
+			errs[e] = err
+			e++
+			continue
+		}
+		err = os.Remove(path)
+		if err != nil && os.Remove(dstFile) == nil {
+			errs[e] = err
+			e++
+			continue
+		}
+		i++
+	}
+	return i, errs[:e]
+}
+
+func LoadFromName(name string) (*Config, error) {
+	configFileDir, err := resolveConfigFileDir()
+	if err != nil {
+		return nil, err
+	}
+	return LoadFromPath(filepath.Join(configFileDir, name+configFileSuffix))
+}
+
+func LoadFromPath(path string) (*Config, error) {
+	name, err := NameFromPath(path)
+	if err != nil {
+		return nil, err
+	}
+	bytes, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, err
+	}
+	if strings.HasSuffix(path, configFileSuffix) {
+		bytes, err = dpapi.Decrypt(bytes, name)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return FromWgQuick(string(bytes), name)
+}
+
+func NameFromPath(path string) (string, error) {
+	name := filepath.Base(path)
+	if !((len(name) > len(configFileSuffix) && strings.HasSuffix(name, configFileSuffix)) ||
+		(len(name) > len(configFileUnencryptedSuffix) && strings.HasSuffix(name, configFileUnencryptedSuffix))) {
+		return "", errors.New("Path must end in either " + configFileSuffix + " or " + configFileUnencryptedSuffix)
+	}
+	if strings.HasSuffix(path, configFileSuffix) {
+		name = strings.TrimSuffix(name, configFileSuffix)
+	} else {
+		name = strings.TrimSuffix(name, configFileUnencryptedSuffix)
+	}
+	return name, nil
+}
+
+func (config *Config) Save() error {
+	configFileDir, err := resolveConfigFileDir()
+	if err != nil {
+		return err
+	}
+	filename := filepath.Join(configFileDir, config.Name+configFileSuffix)
+	bytes := []byte(config.ToWgQuick())
+	bytes, err = dpapi.Encrypt(bytes, config.Name)
+	if err != nil {
+		return err
+	}
+	err = ioutil.WriteFile(filename+".tmp", bytes, 0600)
+	if err != nil {
+		return err
+	}
+	err = os.Rename(filename+".tmp", filename)
+	if err != nil {
+		os.Remove(filename + ".tmp")
+		return err
+	}
+	return nil
+}
+
+func (config *Config) Path() (string, error) {
+	configFileDir, err := resolveConfigFileDir()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(configFileDir, config.Name+configFileSuffix), nil
+}
+
+func DeleteName(name string) error {
+	configFileDir, err := resolveConfigFileDir()
+	if err != nil {
+		return err
+	}
+	return os.Remove(filepath.Join(configFileDir, name+configFileSuffix))
+}
+
+func (config *Config) Delete() error {
+	return DeleteName(config.Name)
+}