config.go

package config

import (
	"errors"
	"io"
	"log"
	"os"
	"os/exec"
	"regexp"
	"runtime"
	"strconv"
	"strings"
	"sync"

	"github.com/jeessy2/ddns-go/v6/util"
	passwordvalidator "github.com/wagslane/go-password-validator"
	"gopkg.in/yaml.v3"
)

// Ipv4Reg IPv4正则
var Ipv4Reg = regexp.MustCompile(`((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])`)

// Ipv6Reg IPv6正则
var Ipv6Reg = regexp.MustCompile(`((([0-9A-Fa-f]{1,4}:){7}([0-9A-Fa-f]{1,4}|:))|(([0-9A-Fa-f]{1,4}:){6}(:[0-9A-Fa-f]{1,4}|((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){5}(((:[0-9A-Fa-f]{1,4}){1,2})|:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){4}(((:[0-9A-Fa-f]{1,4}){1,3})|((:[0-9A-Fa-f]{1,4})?:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){3}(((:[0-9A-Fa-f]{1,4}){1,4})|((:[0-9A-Fa-f]{1,4}){0,2}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){2}(((:[0-9A-Fa-f]{1,4}){1,5})|((:[0-9A-Fa-f]{1,4}){0,3}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){1}(((:[0-9A-Fa-f]{1,4}){1,6})|((:[0-9A-Fa-f]{1,4}){0,4}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(:(((:[0-9A-Fa-f]{1,4}){1,7})|((:[0-9A-Fa-f]{1,4}){0,5}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:)))`)

// DnsConfig 配置
type DnsConfig struct {
	Name string
	Ipv4 struct {
		Enable bool
		// 获取IP类型 url/netInterface
		GetType      string
		URL          string
		NetInterface string
		Cmd          string
		Domains      []string
	}
	Ipv6 struct {
		Enable bool
		// 获取IP类型 url/netInterface
		GetType      string
		URL          string
		NetInterface string
		Cmd          string
		Ipv6Reg      string // ipv6匹配正则表达式
		Domains      []string
	}
	DNS DNS
	TTL string
}

// DNS DNS配置
type DNS struct {
	// 名称。如：alidns,webhook
	Name   string
	ID     string
	Secret string
}

type Config struct {
	DnsConf []DnsConfig
	User
	Webhook
	// 禁止公网访问
	NotAllowWanAccess bool
	// 语言
	Lang string
}

// ConfigCache ConfigCache
type cacheType struct {
	ConfigSingle *Config
	Err          error
	Lock         sync.Mutex
}

var cache = &cacheType{}

// GetConfigCached 获得缓存的配置
func GetConfigCached() (conf Config, err error) {
	cache.Lock.Lock()
	defer cache.Lock.Unlock()

	if cache.ConfigSingle != nil {
		return *cache.ConfigSingle, cache.Err
	}

	// init config
	cache.ConfigSingle = &Config{}

	configFilePath := util.GetConfigFilePath()
	_, err = os.Stat(configFilePath)
	if err != nil {
		cache.Err = err
		return *cache.ConfigSingle, err
	}

	byt, err := os.ReadFile(configFilePath)
	if err != nil {
		util.Log("异常信息: %s", err)
		cache.Err = err
		return *cache.ConfigSingle, err
	}

	err = yaml.Unmarshal(byt, cache.ConfigSingle)
	if err != nil {
		util.Log("异常信息: %s", err)
		cache.Err = err
		return *cache.ConfigSingle, err
	}

	// 未填写登录信息, 确保不能从公网访问
	if cache.ConfigSingle.Username == "" && cache.ConfigSingle.Password == "" {
		cache.ConfigSingle.NotAllowWanAccess = true
	}

	// remove err
	cache.Err = nil
	return *cache.ConfigSingle, err
}

// CompatibleConfig 兼容之前的配置文件
func (conf *Config) CompatibleConfig() {
	// 如配置文件不为空, 兼容之前的语言为中文
	if conf.Lang == "" {
		conf.Lang = "zh"
	}

	// 如果之前密码不为空且不是bcrypt加密后的密码, 把密码加密并保存
	if conf.Password != "" && !util.IsHashedPassword(conf.Password) {
		hashedPwd, err := util.HashPassword(conf.Password)
		if err == nil {
			conf.Password = hashedPwd
			conf.SaveConfig()
		}
	}

	// 兼容v5.0.0之前的配置文件
	if len(conf.DnsConf) > 0 {
		return
	}

	configFilePath := util.GetConfigFilePath()
	_, err := os.Stat(configFilePath)
	if err != nil {
		return
	}
	byt, err := os.ReadFile(configFilePath)
	if err != nil {
		return
	}

	dnsConf := &DnsConfig{}
	err = yaml.Unmarshal(byt, dnsConf)
	if err != nil {
		return
	}
	if len(dnsConf.DNS.Name) > 0 {
		cache.Lock.Lock()
		defer cache.Lock.Unlock()
		conf.DnsConf = append(conf.DnsConf, *dnsConf)
		cache.ConfigSingle = conf
	}
}

// SaveConfig 保存配置
func (conf *Config) SaveConfig() (err error) {
	cache.Lock.Lock()
	defer cache.Lock.Unlock()

	byt, err := yaml.Marshal(conf)
	if err != nil {
		log.Println(err)
		return err
	}

	configFilePath := util.GetConfigFilePath()
	err = os.WriteFile(configFilePath, byt, 0600)
	if err != nil {
		log.Println(err)
		return
	}

	util.Log("配置文件已保存在: %s", configFilePath)

	// 清空配置缓存
	cache.ConfigSingle = nil

	return
}

// 重置密码
func (conf *Config) ResetPassword(newPassword string) {
	// 初始化语言
	util.InitLogLang(conf.Lang)

	// 先检查密码是否安全
	hashedPwd, err := conf.CheckPassword(newPassword)
	if err != nil {
		util.Log(err.Error())
		return
	}

	// 保存配置
	conf.Password = hashedPwd
	conf.SaveConfig()
	util.Log("用户名 %s 的密码已重置成功! 请重启ddns-go", conf.Username)
}

// CheckPassword 检查密码
func (conf *Config) CheckPassword(newPassword string) (hashedPwd string, err error) {
	var minEntropyBits float64 = 50
	if conf.NotAllowWanAccess {
		minEntropyBits = 25
	}
	err = passwordvalidator.Validate(newPassword, minEntropyBits)
	if err != nil {
		return "", errors.New(util.LogStr("密码不安全！尝试使用更复杂的密码"))
	}

	// 加密密码
	hashedPwd, err = util.HashPassword(newPassword)
	if err != nil {
		return "", errors.New(util.LogStr("异常信息: %s", err.Error()))
	}
	return
}

func (conf *DnsConfig) getIpv4AddrFromInterface() string {
	ipv4, _, err := GetNetInterface()
	if err != nil {
		util.Log("从网卡获得IPv4失败")
		return ""
	}

	for _, netInterface := range ipv4 {
		if netInterface.Name == conf.Ipv4.NetInterface && len(netInterface.Address) > 0 {
			return netInterface.Address[0]
		}
	}

	util.Log("从网卡中获得IPv4失败! 网卡名: %s", conf.Ipv4.NetInterface)
	return ""
}

func (conf *DnsConfig) getIpv4AddrFromUrl() string {
	client := util.CreateNoProxyHTTPClient("tcp4")
	urls := strings.Split(conf.Ipv4.URL, ",")
	for _, url := range urls {
		url = strings.TrimSpace(url)
		resp, err := client.Get(url)
		if err != nil {
			util.Log("通过接口获取IPv4失败! 接口地址: %s", url)
			util.Log("异常信息: %s", err)
			continue
		}
		defer resp.Body.Close()
		lr := io.LimitReader(resp.Body, 1024000)
		body, err := io.ReadAll(lr)
		if err != nil {
			util.Log("异常信息: %s", err)
			continue
		}
		result := Ipv4Reg.FindString(string(body))
		if result == "" {
			util.Log("获取IPv4结果失败! 接口: %s ,返回值: %s", url, string(body))
		}
		return result
	}
	return ""
}

func (conf *DnsConfig) getAddrFromCmd(addrType string) string {
	var cmd string
	var comp *regexp.Regexp
	if addrType == "IPv4" {
		cmd = conf.Ipv4.Cmd
		comp = Ipv4Reg
	} else {
		cmd = conf.Ipv6.Cmd
		comp = Ipv6Reg
	}
	// cmd is empty
	if cmd == "" {
		return ""
	}
	// run cmd with proper shell
	var execCmd *exec.Cmd
	if runtime.GOOS == "windows" {
		execCmd = exec.Command("powershell", "-Command", cmd)
	} else {
		// If Bash does not exist, use sh
		_, err := exec.LookPath("bash")
		if err != nil {
			execCmd = exec.Command("sh", "-c", cmd)
		} else {
			execCmd = exec.Command("bash", "-c", cmd)
		}
	}
	// run cmd
	out, err := execCmd.CombinedOutput()
	if err != nil {
		util.Log("获取%s结果失败! 未能成功执行命令：%s, 错误：%q, 退出状态码：%s", addrType, execCmd.String(), out, err)
		return ""
	}
	str := string(out)
	// get result
	result := comp.FindString(str)
	if result == "" {
		util.Log("获取%s结果失败! 命令: %s, 标准输出: %q", addrType, execCmd.String(), str)
	}
	return result
}

// GetIpv4Addr 获得IPv4地址
func (conf *DnsConfig) GetIpv4Addr() string {
	// 判断从哪里获取IP
	switch conf.Ipv4.GetType {
	case "netInterface":
		// 从网卡获取 IP
		return conf.getIpv4AddrFromInterface()
	case "url":
		// 从 URL 获取 IP
		return conf.getIpv4AddrFromUrl()
	case "cmd":
		// 从命令行获取 IP
		return conf.getAddrFromCmd("IPv4")
	default:
		log.Println("IPv4's get IP method is unknown")
		return "" // unknown type
	}
}

func (conf *DnsConfig) getIpv6AddrFromInterface() string {
	_, ipv6, err := GetNetInterface()
	if err != nil {
		util.Log("从网卡获得IPv6失败")
		return ""
	}

	for _, netInterface := range ipv6 {
		if netInterface.Name == conf.Ipv6.NetInterface && len(netInterface.Address) > 0 {
			if conf.Ipv6.Ipv6Reg != "" {
				// 匹配第几个IPv6
				if match, err := regexp.MatchString("@\\d", conf.Ipv6.Ipv6Reg); err == nil && match {
					num, err := strconv.Atoi(conf.Ipv6.Ipv6Reg[1:])
					if err == nil {
						if num > 0 {
							if num <= len(netInterface.Address) {
								return netInterface.Address[num-1]
							}
							util.Log("未找到第 %d 个IPv6地址! 将使用第一个IPv6地址", num)
							return netInterface.Address[0]
						}
						util.Log("IPv6匹配表达式 %s 不正确! 最小从1开始", conf.Ipv6.Ipv6Reg)
						return ""
					}
				}
				// 正则表达式匹配
				util.Log("IPv6将使用正则表达式 %s 进行匹配", conf.Ipv6.Ipv6Reg)
				for i := 0; i < len(netInterface.Address); i++ {
					matched, err := regexp.MatchString(conf.Ipv6.Ipv6Reg, netInterface.Address[i])
					if matched && err == nil {
						util.Log("匹配成功! 匹配到地址: ", netInterface.Address[i])
						return netInterface.Address[i]
					}
				}
				util.Log("没有匹配到任何一个IPv6地址, 将使用第一个地址")
			}
			return netInterface.Address[0]
		}
	}

	util.Log("从网卡中获得IPv6失败! 网卡名: %s", conf.Ipv6.NetInterface)
	return ""
}

func (conf *DnsConfig) getIpv6AddrFromUrl() string {
	client := util.CreateNoProxyHTTPClient("tcp6")
	urls := strings.Split(conf.Ipv6.URL, ",")
	for _, url := range urls {
		url = strings.TrimSpace(url)
		resp, err := client.Get(url)
		if err != nil {
			util.Log("通过接口获取IPv6失败! 接口地址: %s", url)
			util.Log("异常信息: %s", err)
			continue
		}

		defer resp.Body.Close()
		lr := io.LimitReader(resp.Body, 1024000)
		body, err := io.ReadAll(lr)
		if err != nil {
			util.Log("异常信息: %s", err)
			continue
		}
		result := Ipv6Reg.FindString(string(body))
		if result == "" {
			util.Log("获取IPv6结果失败! 接口: %s ,返回值: %s", url, result)
		}
		return result
	}
	return ""
}

// GetIpv6Addr 获得IPv6地址
func (conf *DnsConfig) GetIpv6Addr() (result string) {
	// 判断从哪里获取IP
	switch conf.Ipv6.GetType {
	case "netInterface":
		// 从网卡获取 IP
		return conf.getIpv6AddrFromInterface()
	case "url":
		// 从 URL 获取 IP
		return conf.getIpv6AddrFromUrl()
	case "cmd":
		// 从命令行获取 IP
		return conf.getAddrFromCmd("IPv6")
	default:
		log.Println("IPv6's get IP method is unknown")
		return "" // unknown type
	}
}