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main.go
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main.go
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package main
import (
"context"
"crypto/tls"
"errors"
"fmt"
"io"
"net"
"net/http"
"net/url"
"os"
"os/exec"
"path/filepath"
"runtime"
"strings"
"time"
"github.com/AlecAivazis/survey/v2"
bpc "github.com/DaRealFreak/cloudflare-bp-go"
"github.com/blang/semver"
"github.com/ebi-yade/altsvc-go"
"github.com/go-ping/ping"
"github.com/gorilla/websocket"
"github.com/nezhahq/go-github-selfupdate/selfupdate"
"github.com/quic-go/quic-go/http3"
"github.com/shirou/gopsutil/v3/disk"
"github.com/shirou/gopsutil/v3/host"
psnet "github.com/shirou/gopsutil/v3/net"
flag "github.com/spf13/pflag"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials"
"google.golang.org/grpc/credentials/insecure"
"github.com/nezhahq/agent/model"
"github.com/nezhahq/agent/pkg/monitor"
"github.com/nezhahq/agent/pkg/processgroup"
"github.com/nezhahq/agent/pkg/pty"
"github.com/nezhahq/agent/pkg/util"
pb "github.com/nezhahq/agent/proto"
)
type AgentCliParam struct {
SkipConnectionCount bool // 跳过连接数检查
SkipProcsCount bool // 跳过进程数量检查
DisableAutoUpdate bool // 关闭自动更新
DisableForceUpdate bool // 关闭强制更新
DisableCommandExecute bool // 关闭命令执行
Debug bool // debug模式
Server string // 服务器地址
ClientSecret string // 客户端密钥
ReportDelay int // 报告间隔
TLS bool // 是否使用TLS加密传输至服务端
Version bool // 当前版本号
}
var (
version string
arch string
client pb.NezhaServiceClient
inited bool
)
var (
agentCliParam AgentCliParam
agentConfig model.AgentConfig
httpClient = &http.Client{
CheckRedirect: func(req *http.Request, via []*http.Request) error {
return http.ErrUseLastResponse
},
Timeout: time.Second * 30,
}
httpClient3 = &http.Client{
CheckRedirect: func(req *http.Request, via []*http.Request) error {
return http.ErrUseLastResponse
},
Timeout: time.Second * 30,
Transport: &http3.RoundTripper{},
}
)
const (
delayWhenError = time.Second * 10 // Agent 重连间隔
networkTimeOut = time.Second * 5 // 普通网络超时
macOSChromeUA = ""
)
func init() {
net.DefaultResolver.PreferGo = true // 使用 Go 内置的 DNS 解析器解析域名
net.DefaultResolver.Dial = func(ctx context.Context, network, address string) (net.Conn, error) {
d := net.Dialer{
Timeout: time.Second * 5,
}
dnsServers := util.DNSServersAll
if len(agentConfig.DNS) > 0 {
dnsServers = agentConfig.DNS
}
index := int(time.Now().Unix()) % int(len(dnsServers))
queue := generateQueue(index, len(dnsServers))
var conn net.Conn
var err error
for i := 0; i < len(queue); i++ {
conn, err = d.DialContext(ctx, "udp", dnsServers[queue[i]])
if err == nil {
return conn, nil
}
}
return nil, err
}
flag.CommandLine.ParseErrorsWhitelist.UnknownFlags = true
http.DefaultClient.Timeout = time.Second * 5
httpClient.Transport = bpc.AddCloudFlareByPass(httpClient.Transport, bpc.Options{
AddMissingHeaders: true,
Headers: map[string]string{
"Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8",
"Accept-Language": "en-US,en;q=0.5",
"User-Agent": monitor.MacOSChromeUA,
},
})
ex, err := os.Executable()
if err != nil {
panic(err)
}
agentConfig.Read(filepath.Dir(ex) + "/config.yml")
}
func main() {
// windows环境处理
if runtime.GOOS == "windows" {
hostArch, err := host.KernelArch()
if err != nil {
panic(err)
}
if hostArch == "i386" {
hostArch = "386"
}
if hostArch == "i686" || hostArch == "ia64" || hostArch == "x86_64" {
hostArch = "amd64"
}
if hostArch == "aarch64" {
hostArch = "arm64"
}
if arch != hostArch {
panic(fmt.Sprintf("与当前系统不匹配,当前运行 %s_%s, 需要下载 %s_%s", runtime.GOOS, arch, runtime.GOOS, hostArch))
}
}
// 来自于 GoReleaser 的版本号
monitor.Version = version
// 初始化运行参数
var isEditAgentConfig bool
flag.BoolVarP(&agentCliParam.Debug, "debug", "d", false, "开启调试信息")
flag.BoolVarP(&isEditAgentConfig, "edit-agent-config", "c", false, "修改要监控的网卡/分区名单,修改自定义 DNS")
flag.StringVarP(&agentCliParam.Server, "server", "s", "localhost:5555", "管理面板RPC端口")
flag.StringVarP(&agentCliParam.ClientSecret, "password", "p", "", "Agent连接Secret")
flag.IntVar(&agentCliParam.ReportDelay, "report-delay", 1, "系统状态上报间隔")
flag.BoolVar(&agentCliParam.SkipConnectionCount, "skip-conn", false, "不监控连接数")
flag.BoolVar(&agentCliParam.SkipProcsCount, "skip-procs", false, "不监控进程数")
flag.BoolVar(&agentCliParam.DisableCommandExecute, "disable-command-execute", false, "禁止在此机器上执行命令")
flag.BoolVar(&agentCliParam.DisableAutoUpdate, "disable-auto-update", false, "禁用自动升级")
flag.BoolVar(&agentCliParam.DisableForceUpdate, "disable-force-update", false, "禁用强制升级")
flag.BoolVar(&agentCliParam.TLS, "tls", false, "启用SSL/TLS加密")
flag.BoolVarP(&agentCliParam.Version, "version", "v", false, "查看当前版本号")
flag.Parse()
if agentCliParam.Version {
fmt.Println(version)
return
}
if isEditAgentConfig {
editAgentConfig()
return
}
if agentCliParam.ClientSecret == "" {
flag.Usage()
return
}
if agentCliParam.ReportDelay < 1 || agentCliParam.ReportDelay > 4 {
println("report-delay 的区间为 1-4")
return
}
run()
}
func run() {
auth := model.AuthHandler{
ClientSecret: agentCliParam.ClientSecret,
}
// 下载远程命令执行需要的终端
if !agentCliParam.DisableCommandExecute {
go pty.DownloadDependency()
}
// 上报服务器信息
go reportState()
// 更新IP信息
go monitor.UpdateIP()
// 定时检查更新
if _, err := semver.Parse(version); err == nil && !agentCliParam.DisableAutoUpdate {
doSelfUpdate(true)
go func() {
for range time.Tick(20 * time.Minute) {
doSelfUpdate(true)
}
}()
}
var err error
var conn *grpc.ClientConn
retry := func() {
inited = false
println("Error to close connection ...")
if conn != nil {
conn.Close()
}
time.Sleep(delayWhenError)
println("Try to reconnect ...")
}
for {
timeOutCtx, cancel := context.WithTimeout(context.Background(), networkTimeOut)
var securityOption grpc.DialOption
if agentCliParam.TLS {
securityOption = grpc.WithTransportCredentials(credentials.NewTLS(&tls.Config{MinVersion: tls.VersionTLS12}))
} else {
securityOption = grpc.WithTransportCredentials(insecure.NewCredentials())
}
conn, err = grpc.DialContext(timeOutCtx, agentCliParam.Server, securityOption, grpc.WithPerRPCCredentials(&auth))
if err != nil {
println("与面板建立连接失败:", err)
cancel()
retry()
continue
}
cancel()
client = pb.NewNezhaServiceClient(conn)
// 第一步注册
timeOutCtx, cancel = context.WithTimeout(context.Background(), networkTimeOut)
_, err = client.ReportSystemInfo(timeOutCtx, monitor.GetHost(&agentConfig).PB())
if err != nil {
println("上报系统信息失败:", err)
cancel()
retry()
continue
}
cancel()
inited = true
// 执行 Task
tasks, err := client.RequestTask(context.Background(), monitor.GetHost(&agentConfig).PB())
if err != nil {
println("请求任务失败:", err)
retry()
continue
}
err = receiveTasks(tasks)
println("receiveTasks exit to main:", err)
retry()
}
}
func receiveTasks(tasks pb.NezhaService_RequestTaskClient) error {
var err error
defer println("receiveTasks exit", time.Now(), "=>", err)
for {
var task *pb.Task
task, err = tasks.Recv()
if err != nil {
return err
}
go func() {
defer func() {
if err := recover(); err != nil {
println("task panic", task, err)
}
}()
doTask(task)
}()
}
}
func doTask(task *pb.Task) {
var result pb.TaskResult
result.Id = task.GetId()
result.Type = task.GetType()
switch task.GetType() {
case model.TaskTypeTerminal:
handleTerminalTask(task)
case model.TaskTypeHTTPGET:
handleHttpGetTask(task, &result)
case model.TaskTypeICMPPing:
handleIcmpPingTask(task, &result)
case model.TaskTypeTCPPing:
handleTcpPingTask(task, &result)
case model.TaskTypeCommand:
handleCommandTask(task, &result)
case model.TaskTypeUpgrade:
handleUpgradeTask(task, &result)
case model.TaskTypeKeepalive:
return
default:
println("不支持的任务:", task)
}
client.ReportTask(context.Background(), &result)
}
// reportState 向server上报状态信息
func reportState() {
var lastReportHostInfo time.Time
var err error
defer println("reportState exit", time.Now(), "=>", err)
for {
// 为了更准确的记录时段流量,inited 后再上传状态信息
if client != nil && inited {
monitor.TrackNetworkSpeed(&agentConfig)
timeOutCtx, cancel := context.WithTimeout(context.Background(), networkTimeOut)
_, err = client.ReportSystemState(timeOutCtx, monitor.GetState(&agentConfig, agentCliParam.SkipConnectionCount, agentCliParam.SkipProcsCount).PB())
cancel()
if err != nil {
println("reportState error", err)
time.Sleep(delayWhenError)
}
// 每10分钟重新获取一次硬件信息
if lastReportHostInfo.Before(time.Now().Add(-10 * time.Minute)) {
lastReportHostInfo = time.Now()
client.ReportSystemInfo(context.Background(), monitor.GetHost(&agentConfig).PB())
}
}
time.Sleep(time.Second * time.Duration(agentCliParam.ReportDelay))
}
}
// doSelfUpdate 执行更新检查 如果更新成功则会结束进程
func doSelfUpdate(useLocalVersion bool) {
v := semver.MustParse("0.1.0")
if useLocalVersion {
v = semver.MustParse(version)
}
println("检查更新:", v)
latest, err := selfupdate.UpdateSelf(v, "nezhahq/agent")
if err != nil {
println("更新失败:", err)
return
}
if !latest.Version.Equals(v) {
println("已经更新至:", latest.Version, " 正在结束进程")
os.Exit(1)
}
}
func handleUpgradeTask(task *pb.Task, result *pb.TaskResult) {
if agentCliParam.DisableForceUpdate {
return
}
doSelfUpdate(false)
}
func handleTcpPingTask(task *pb.Task, result *pb.TaskResult) {
start := time.Now()
conn, err := net.DialTimeout("tcp", task.GetData(), time.Second*10)
if err == nil {
conn.Write([]byte("ping\n"))
conn.Close()
result.Delay = float32(time.Since(start).Microseconds()) / 1000.0
result.Successful = true
} else {
result.Data = err.Error()
}
}
func handleIcmpPingTask(task *pb.Task, result *pb.TaskResult) {
pinger, err := ping.NewPinger(task.GetData())
if err == nil {
pinger.SetPrivileged(true)
pinger.Count = 5
pinger.Timeout = time.Second * 20
err = pinger.Run() // Blocks until finished.
}
if err == nil {
stat := pinger.Statistics()
if stat.PacketsRecv == 0 {
result.Data = "pockets recv 0"
return
}
result.Delay = float32(stat.AvgRtt.Microseconds()) / 1000.0
result.Successful = true
} else {
result.Data = err.Error()
}
}
func handleHttpGetTask(task *pb.Task, result *pb.TaskResult) {
start := time.Now()
taskUrl := task.GetData()
resp, err := httpClient.Get(taskUrl)
checkHttpResp(taskUrl, start, resp, err, result)
}
func checkHttpResp(taskUrl string, start time.Time, resp *http.Response, err error, result *pb.TaskResult) {
if err == nil {
defer resp.Body.Close()
_, err = io.Copy(io.Discard, resp.Body)
}
if err == nil {
// 检查 HTTP Response 状态
result.Delay = float32(time.Since(start).Microseconds()) / 1000.0
if resp.StatusCode > 399 || resp.StatusCode < 200 {
err = errors.New("\n应用错误:" + resp.Status)
}
}
if err == nil {
// 检查 SSL 证书信息
if resp.TLS != nil && len(resp.TLS.PeerCertificates) > 0 {
c := resp.TLS.PeerCertificates[0]
result.Data = c.Issuer.CommonName + "|" + c.NotAfter.String()
}
altSvc := resp.Header.Get("Alt-Svc")
if altSvc != "" {
checkAltSvc(start, altSvc, taskUrl, result)
} else {
result.Successful = true
}
} else {
// HTTP 请求失败
result.Data = err.Error()
}
}
func checkAltSvc(start time.Time, altSvcStr string, taskUrl string, result *pb.TaskResult) {
altSvcList, err := altsvc.Parse(altSvcStr)
if err != nil {
result.Data = err.Error()
result.Successful = false
return
}
parsedUrl, _ := url.Parse(taskUrl)
originalHost := parsedUrl.Hostname()
originalPort := parsedUrl.Port()
if originalPort == "" {
switch parsedUrl.Scheme {
case "http":
originalPort = "80"
case "https":
originalPort = "443"
}
}
altAuthorityHost := ""
altAuthorityPort := ""
altAuthorityProtocol := ""
for _, altSvc := range altSvcList {
altAuthorityPort = altSvc.AltAuthority.Port
if altSvc.AltAuthority.Host != "" {
altAuthorityHost = altSvc.AltAuthority.Host
altAuthorityProtocol = altSvc.ProtocolID
break
}
}
if altAuthorityHost == "" {
altAuthorityHost = originalHost
}
if altAuthorityHost == originalHost && altAuthorityPort == originalPort {
result.Successful = true
return
}
altAuthorityUrl := "https://" + altAuthorityHost + ":" + altAuthorityPort + "/"
req, _ := http.NewRequest("GET", altAuthorityUrl, nil)
req.Host = originalHost
client := httpClient
if strings.HasPrefix(altAuthorityProtocol, "h3") {
client = httpClient3
}
resp, err := client.Do(req)
checkHttpResp(altAuthorityUrl, start, resp, err, result)
}
func handleCommandTask(task *pb.Task, result *pb.TaskResult) {
if agentCliParam.DisableCommandExecute {
result.Data = "此 Agent 已禁止命令执行"
return
}
startedAt := time.Now()
var cmd *exec.Cmd
var endCh = make(chan struct{})
pg, err := processgroup.NewProcessExitGroup()
if err != nil {
// 进程组创建失败,直接退出
result.Data = err.Error()
return
}
timeout := time.NewTimer(time.Hour * 2)
if util.IsWindows() {
cmd = exec.Command("cmd", "/c", task.GetData()) // #nosec
} else {
cmd = exec.Command("sh", "-c", task.GetData()) // #nosec
}
cmd.Env = os.Environ()
pg.AddProcess(cmd)
go func() {
select {
case <-timeout.C:
result.Data = "任务执行超时\n"
close(endCh)
pg.Dispose()
case <-endCh:
timeout.Stop()
}
}()
output, err := cmd.Output()
if err != nil {
result.Data += fmt.Sprintf("%s\n%s", string(output), err.Error())
} else {
close(endCh)
result.Data = string(output)
result.Successful = true
}
pg.Dispose()
result.Delay = float32(time.Since(startedAt).Seconds())
}
type WindowSize struct {
Cols uint32
Rows uint32
}
func handleTerminalTask(task *pb.Task) {
if agentCliParam.DisableCommandExecute {
println("此 Agent 已禁止命令执行")
return
}
var terminal model.TerminalTask
err := util.Json.Unmarshal([]byte(task.GetData()), &terminal)
if err != nil {
println("Terminal 任务解析错误:", err)
return
}
protocol := "ws"
if terminal.UseSSL {
protocol += "s"
}
header := http.Header{}
header.Add("Secret", agentCliParam.ClientSecret)
// 目前只兼容Cloudflare验证
// 后续可能需要兼容更多的Cookie验证情况
if terminal.Cookie != "" {
cfCookie := fmt.Sprintf("CF_Authorization=%s", terminal.Cookie)
header.Add("Cookie", cfCookie)
}
conn, _, err := websocket.DefaultDialer.Dial(fmt.Sprintf("%s://%s/terminal/%s", protocol, terminal.Host, terminal.Session), header)
if err != nil {
println("Terminal 连接失败:", err)
return
}
defer conn.Close()
tty, err := pty.Start()
if err != nil {
println("Terminal pty.Start失败:", err)
return
}
defer func() {
err := tty.Close()
conn.Close()
println("terminal exit", terminal.Session, err)
}()
println("terminal init", terminal.Session)
go func() {
for {
buf := make([]byte, 1024)
read, err := tty.Read(buf)
if err != nil {
conn.WriteMessage(websocket.TextMessage, []byte(err.Error()))
conn.Close()
return
}
conn.WriteMessage(websocket.BinaryMessage, buf[:read])
}
}()
for {
messageType, reader, err := conn.NextReader()
if err != nil {
return
}
if messageType == websocket.TextMessage {
continue
}
dataTypeBuf := make([]byte, 1)
read, err := reader.Read(dataTypeBuf)
if err != nil {
conn.WriteMessage(websocket.TextMessage, []byte("Unable to read message type from reader"))
return
}
if read != 1 {
return
}
switch dataTypeBuf[0] {
case 0:
io.Copy(tty, reader)
case 1:
decoder := util.Json.NewDecoder(reader)
var resizeMessage WindowSize
err := decoder.Decode(&resizeMessage)
if err != nil {
continue
}
tty.Setsize(resizeMessage.Cols, resizeMessage.Rows)
}
}
}
// 修改Agent要监控的网卡与硬盘分区
func editAgentConfig() {
nc, err := psnet.IOCounters(true)
if err != nil {
panic(err)
}
var nicAllowlistOptions []string
for _, v := range nc {
nicAllowlistOptions = append(nicAllowlistOptions, v.Name)
}
var diskAllowlistOptions []string
diskList, err := disk.Partitions(false)
if err != nil {
panic(err)
}
for _, p := range diskList {
diskAllowlistOptions = append(diskAllowlistOptions, fmt.Sprintf("%s\t%s\t%s", p.Mountpoint, p.Fstype, p.Device))
}
var qs = []*survey.Question{
{
Name: "nic",
Prompt: &survey.MultiSelect{
Message: "选择要监控的网卡",
Options: nicAllowlistOptions,
},
},
{
Name: "disk",
Prompt: &survey.MultiSelect{
Message: "选择要监控的硬盘分区",
Options: diskAllowlistOptions,
},
},
{
Name: "dns",
Prompt: &survey.Input{
Message: "自定义 DNS,可输入空格跳过,如 1.1.1.1:53,1.0.0.1:53",
Default: strings.Join(agentConfig.DNS, ","),
},
},
}
answers := struct {
Nic []string
Disk []string
DNS string
}{}
err = survey.Ask(qs, &answers, survey.WithValidator(survey.Required))
if err != nil {
fmt.Println("选择错误", err.Error())
return
}
agentConfig.HardDrivePartitionAllowlist = []string{}
for _, v := range answers.Disk {
agentConfig.HardDrivePartitionAllowlist = append(agentConfig.HardDrivePartitionAllowlist, strings.Split(v, "\t")[0])
}
agentConfig.NICAllowlist = make(map[string]bool)
for _, v := range answers.Nic {
agentConfig.NICAllowlist[v] = true
}
dnsServers := strings.TrimSpace(answers.DNS)
if dnsServers != "" {
agentConfig.DNS = strings.Split(dnsServers, ",")
for _, s := range agentConfig.DNS {
host, _, err := net.SplitHostPort(s)
if err == nil {
if net.ParseIP(host) == nil {
err = errors.New("格式错误")
}
}
if err != nil {
panic(fmt.Sprintf("自定义 DNS 格式错误:%s %v", s, err))
}
}
} else {
agentConfig.DNS = []string{}
}
if err = agentConfig.Save(); err != nil {
panic(err)
}
fmt.Println("修改自定义配置成功,重启 Agent 后生效")
}
func println(v ...interface{}) {
if agentCliParam.Debug {
fmt.Printf("NEZHA@%s>> ", time.Now().Format("2006-01-02 15:04:05"))
fmt.Println(v...)
}
}
func generateQueue(start int, size int) []int {
var result []int
for i := start; i < start+size; i++ {
if i < size {
result = append(result, i)
} else {
result = append(result, i-size)
}
}
return result
}