AdGuardHome/internal/home/controlupdate.go
Ainar Garipov 2a1ad532f4 Pull request: home: rm unnecessary locking in update; refactor
Merge in DNS/adguard-home from 4499-rm-unnecessary-locking to master

Squashed commit of the following:

commit 6d70472506dd0fd69225454c73d9f7f6a208b76b
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Mon Apr 25 17:26:54 2022 +0300

    home: rm unnecessary locking in update; refactor
2022-04-25 18:41:39 +03:00

219 lines
5.5 KiB
Go

package home
import (
"context"
"encoding/json"
"fmt"
"net/http"
"os"
"os/exec"
"path/filepath"
"runtime"
"syscall"
"time"
"github.com/AdguardTeam/AdGuardHome/internal/aghhttp"
"github.com/AdguardTeam/AdGuardHome/internal/aghnet"
"github.com/AdguardTeam/AdGuardHome/internal/updater"
"github.com/AdguardTeam/golibs/errors"
"github.com/AdguardTeam/golibs/log"
)
// temporaryError is the interface for temporary errors from the Go standard
// library.
type temporaryError interface {
error
Temporary() (ok bool)
}
// Get the latest available version from the Internet
func handleGetVersionJSON(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json")
resp := &versionResponse{}
if Context.disableUpdate {
resp.Disabled = true
err := json.NewEncoder(w).Encode(resp)
if err != nil {
aghhttp.Error(r, w, http.StatusInternalServerError, "writing body: %s", err)
}
return
}
req := &struct {
Recheck bool `json:"recheck_now"`
}{}
var err error
if r.ContentLength != 0 {
err = json.NewDecoder(r.Body).Decode(req)
if err != nil {
aghhttp.Error(r, w, http.StatusBadRequest, "parsing request: %s", err)
return
}
}
err = requestVersionInfo(resp, req.Recheck)
if err != nil {
// Don't wrap the error, because it's informative enough as is.
aghhttp.Error(r, w, http.StatusBadGateway, "%s", err)
return
}
err = resp.setAllowedToAutoUpdate()
if err != nil {
// Don't wrap the error, because it's informative enough as is.
aghhttp.Error(r, w, http.StatusInternalServerError, "%s", err)
return
}
err = json.NewEncoder(w).Encode(resp)
if err != nil {
aghhttp.Error(r, w, http.StatusInternalServerError, "writing body: %s", err)
}
}
// requestVersionInfo sets the VersionInfo field of resp if it can reach the
// update server.
func requestVersionInfo(resp *versionResponse, recheck bool) (err error) {
for i := 0; i != 3; i++ {
resp.VersionInfo, err = Context.updater.VersionInfo(recheck)
if err != nil {
var terr temporaryError
if errors.As(err, &terr) && terr.Temporary() {
// Temporary network error. This case may happen while we're
// restarting our DNS server. Log and sleep for some time.
//
// See https://github.com/AdguardTeam/AdGuardHome/issues/934.
d := time.Duration(i) * time.Second
log.Info("update: temp net error: %q; sleeping for %s and retrying", err, d)
time.Sleep(d)
continue
}
}
break
}
if err != nil {
vcu := Context.updater.VersionCheckURL()
return fmt.Errorf("getting version info from %s: %s", vcu, err)
}
return nil
}
// handleUpdate performs an update to the latest available version procedure.
func handleUpdate(w http.ResponseWriter, r *http.Request) {
if Context.updater.NewVersion() == "" {
aghhttp.Error(r, w, http.StatusBadRequest, "/update request isn't allowed now")
return
}
err := Context.updater.Update()
if err != nil {
aghhttp.Error(r, w, http.StatusInternalServerError, "%s", err)
return
}
aghhttp.OK(w)
if f, ok := w.(http.Flusher); ok {
f.Flush()
}
// The background context is used because the underlying functions wrap
// it with timeout and shut down the server, which handles current
// request. It also should be done in a separate goroutine due to the
// same reason.
go func() {
finishUpdate(context.Background())
}()
}
// versionResponse is the response for /control/version.json endpoint.
type versionResponse struct {
updater.VersionInfo
Disabled bool `json:"disabled"`
}
// setAllowedToAutoUpdate sets CanAutoUpdate to true if AdGuard Home is actually
// allowed to perform an automatic update by the OS.
func (vr *versionResponse) setAllowedToAutoUpdate() (err error) {
if vr.CanAutoUpdate == nil || !*vr.CanAutoUpdate {
return
}
tlsConf := &tlsConfigSettings{}
Context.tls.WriteDiskConfig(tlsConf)
canUpdate := true
if tlsConfUsesPrivilegedPorts(tlsConf) || config.BindPort < 1024 || config.DNS.Port < 1024 {
canUpdate, err = aghnet.CanBindPrivilegedPorts()
if err != nil {
return fmt.Errorf("checking ability to bind privileged ports: %w", err)
}
}
vr.CanAutoUpdate = &canUpdate
return nil
}
// tlsConfUsesPrivilegedPorts returns true if the provided TLS configuration
// indicates that privileged ports are used.
func tlsConfUsesPrivilegedPorts(c *tlsConfigSettings) (ok bool) {
return c.Enabled && (c.PortHTTPS < 1024 || c.PortDNSOverTLS < 1024 || c.PortDNSOverQUIC < 1024)
}
// finishUpdate completes an update procedure.
func finishUpdate(ctx context.Context) {
log.Info("Stopping all tasks")
cleanup(ctx)
cleanupAlways()
exeName := "AdGuardHome"
if runtime.GOOS == "windows" {
exeName = "AdGuardHome.exe"
}
curBinName := filepath.Join(Context.workDir, exeName)
if runtime.GOOS == "windows" {
if Context.runningAsService {
// Note:
// we can't restart the service via "kardianos/service" package - it kills the process first
// we can't start a new instance - Windows doesn't allow it
cmd := exec.Command("cmd", "/c", "net stop AdGuardHome & net start AdGuardHome")
err := cmd.Start()
if err != nil {
log.Fatalf("exec.Command() failed: %s", err)
}
os.Exit(0)
}
cmd := exec.Command(curBinName, os.Args[1:]...)
log.Info("Restarting: %v", cmd.Args)
cmd.Stdin = os.Stdin
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
err := cmd.Start()
if err != nil {
log.Fatalf("exec.Command() failed: %s", err)
}
os.Exit(0)
} else {
log.Info("Restarting: %v", os.Args)
err := syscall.Exec(curBinName, os.Args, os.Environ())
if err != nil {
log.Fatalf("syscall.Exec() failed: %s", err)
}
// Unreachable code
}
}