chore: set User-Agent on all outgoing HTTP requests (#10867)

It's only polite, and it enables better troubleshooting in situations
like weird-ass requests to the upgrades download service.

---------

Signed-off-by: Jakob Borg <jakob@kastelo.net>

cmd/infra/stupgrades/main.go

@@ -224,7 +224,7 @@ func filterForLatest(rels []upgrade.Release) []upgrade.Release {
 	return filtered
 }
 
-var userAgentOSArchExp = regexp.MustCompile(`^syncthing.*\(.+ (\w+)-(\w+)\)$`)
+var userAgentOSArchExp = regexp.MustCompile(`^[Ss]yncthing.*\(.+ (\w+)-(\w+)\)$`)
 
 func filterForCompatibility(rels []upgrade.Release, ua, osv string) []upgrade.Release {
 	osArch := userAgentOSArchExp.FindStringSubmatch(ua)

cmd/syncthing/cli/client.go

@@ -18,6 +18,7 @@ import (
 	"net/http"
 	"strings"
 
+	"github.com/syncthing/syncthing/lib/build"
 	"github.com/syncthing/syncthing/lib/config"
 	"github.com/syncthing/syncthing/lib/events"
 	"github.com/syncthing/syncthing/lib/locations"
@@ -115,6 +116,7 @@ func (c *apiClient) Endpoint() string {
 
 func (c *apiClient) Do(req *http.Request) (*http.Response, error) {
 	req.Header.Set("X-Api-Key", c.apikey)
+	req.Header.Set("User-Agent", build.UserAgent())
 	resp, err := c.Client.Do(req)
 	if err != nil {
 		return nil, err

cmd/syncthing/crash_reporting.go

@@ -20,6 +20,7 @@ import (
 	"time"
 
 	"github.com/syncthing/syncthing/internal/slogutil"
+	"github.com/syncthing/syncthing/lib/build"
 )
 
 const (
@@ -81,6 +82,7 @@ func uploadPanicLog(ctx context.Context, urlBase, file string) error {
 	if err != nil {
 		return err
 	}
+	headReq.Header.Set("User-Agent", build.UserAgent())
 
 	// Set a reasonable timeout on the HEAD request
 	headCtx, headCancel := context.WithTimeout(ctx, headRequestTimeout)
@@ -101,6 +103,7 @@ func uploadPanicLog(ctx context.Context, urlBase, file string) error {
 	if err != nil {
 		return err
 	}
+	putReq.Header.Set("User-Agent", build.UserAgent())
 
 	// Set a reasonable timeout on the PUT request
 	putCtx, putCancel := context.WithTimeout(ctx, putRequestTimeout)

cmd/syncthing/main.go

@@ -374,6 +374,7 @@ func upgradeViaRest() error {
 	target := u.String()
 	r, _ := http.NewRequest(http.MethodPost, target, nil)
 	r.Header.Set("X-Api-Key", cfg.GUI().APIKey)
+	r.Header.Set("User-Agent", build.UserAgent())
 
 	tr := &http.Transport{
 		DialContext:     dialer.DialContext,
@@ -955,6 +956,7 @@ func (c browserCmd) Run() error {
 		if err != nil {
 			return err
 		}
+		req.Header.Set("User-Agent", build.UserAgent())
 		_, err = http.DefaultClient.Do(req) //nolint:bodyclose // we're exiting in a millisecond
 		if err != nil {
 			slog.Error("GUI not available", slogutil.Error(err))

lib/build/build.go

@@ -127,6 +127,10 @@ func LongVersionFor(program string) string {
 	return v
 }
 
+func UserAgent() string {
+	return fmt.Sprintf(`Syncthing/%s (%s %s-%s)`, strings.TrimPrefix(Version, "v"), runtime.Version(), runtime.GOOS, runtime.GOARCH)
+}
+
 func TagsList() []string {
 	tags := strings.Split(Tags, ",")
 	if len(tags) == 1 && tags[0] == "" {

lib/discover/global.go

@@ -25,6 +25,7 @@ import (
 	"golang.org/x/net/http2"
 
 	"github.com/syncthing/syncthing/internal/slogutil"
+	"github.com/syncthing/syncthing/lib/build"
 	"github.com/syncthing/syncthing/lib/connections/registry"
 	"github.com/syncthing/syncthing/lib/dialer"
 	"github.com/syncthing/syncthing/lib/events"
@@ -454,6 +455,7 @@ func (c *contextClient) Get(ctx context.Context, url string) (*http.Response, er
 	if err != nil {
 		return nil, err
 	}
+	req.Header.Set("User-Agent", build.UserAgent())
 	return c.Client.Do(req)
 }
 
@@ -463,6 +465,7 @@ func (c *contextClient) Post(ctx context.Context, url, ctype string, data io.Rea
 		return nil, err
 	}
 	req.Header.Set("Content-Type", ctype)
+	req.Header.Set("User-Agent", build.UserAgent())
 	return c.Client.Do(req)
 }
 

lib/relay/client/dynamic.go

@@ -14,6 +14,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/syncthing/syncthing/lib/build"
 	"github.com/syncthing/syncthing/lib/osutil"
 	"github.com/syncthing/syncthing/lib/rand"
 	"github.com/syncthing/syncthing/lib/relay/protocol"
@@ -53,6 +54,7 @@ func (c *dynamicClient) serve(ctx context.Context) error {
 		l.Debugln(c, "failed to lookup dynamic relays", err)
 		return err
 	}
+	req.Header.Set("User-Agent", build.UserAgent())
 	data, err := http.DefaultClient.Do(req)
 	if err != nil {
 		l.Debugln(c, "failed to lookup dynamic relays", err)

lib/upgrade/upgrade_supported.go

@@ -15,20 +15,19 @@ import (
 	"compress/gzip"
 	"encoding/json"
 	"errors"
-	"fmt"
 	"io"
 	"log/slog"
 	"net/http"
 	"os"
 	"path"
 	"path/filepath"
-	"runtime"
 	"sort"
 	"strings"
 	"time"
 
 	"github.com/shirou/gopsutil/v4/host"
 	"github.com/syncthing/syncthing/internal/slogutil"
+	"github.com/syncthing/syncthing/lib/build"
 	"github.com/syncthing/syncthing/lib/dialer"
 	"github.com/syncthing/syncthing/lib/signature"
 	"github.com/syncthing/syncthing/lib/tlsutil"
@@ -79,13 +78,13 @@ func init() {
 	osVersion = strings.TrimSpace(osVersion)
 }
 
-func upgradeClientGet(url, version string) (*http.Response, error) {
+func upgradeClientGet(url string) (*http.Response, error) {
 	req, err := http.NewRequest(http.MethodGet, url, nil)
 	if err != nil {
 		return nil, err
 	}
 
-	req.Header.Set("User-Agent", fmt.Sprintf(`syncthing %s (%s %s-%s)`, version, runtime.Version(), runtime.GOOS, runtime.GOARCH))
+	req.Header.Set("User-Agent", build.UserAgent())
 	if osVersion != "" {
 		req.Header.Set("Syncthing-Os-Version", osVersion)
 	}
@@ -95,7 +94,7 @@ func upgradeClientGet(url, version string) (*http.Response, error) {
 // FetchLatestReleases returns the latest releases. The "current" parameter
 // is used for setting the User-Agent only.
 func FetchLatestReleases(releasesURL, current string) []Release {
-	resp, err := upgradeClientGet(releasesURL, current)
+	resp, err := upgradeClientGet(releasesURL)
 	if err != nil {
 		slog.Warn("Failed to fetch latest release information", slogutil.Error(err))
 		return nil
@@ -227,6 +226,7 @@ func readRelease(archiveName, dir, url string) (string, error) {
 	}
 
 	req.Header.Add("Accept", "application/octet-stream")
+	req.Header.Set("User-Agent", build.UserAgent())
 	resp, err := upgradeClient.Do(req)
 	if err != nil {
 		return "", err

lib/upnp/upnp.go

@@ -337,7 +337,12 @@ func parseResponse(ctx context.Context, deviceType string, addr *net.UDPAddr, re
 	}
 
 	deviceUUID := strings.TrimPrefix(strings.Split(deviceUSN, "::")[0], "uuid:")
-	response, err = http.Get(deviceDescriptionLocation)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, deviceDescriptionLocation, nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("User-Agent", build.UserAgent())
+	response, err = http.DefaultClient.Do(req)
 	if err != nil {
 		return nil, err
 	}
@@ -582,7 +587,7 @@ func soapRequestWithIP(ctx context.Context, url, service, function, message stri
 	}
 	req.Close = true
 	req.Header.Set("Content-Type", `text/xml; charset="utf-8"`)
-	req.Header.Set("User-Agent", "syncthing/1.0")
+	req.Header.Set("User-Agent", build.UserAgent())
 	req.Header["SOAPAction"] = []string{fmt.Sprintf(`"%s#%s"`, service, function)} // Enforce capitalization in header-entry for sensitive routers. See issue #1696
 	req.Header.Set("Connection", "Close")
 	req.Header.Set("Cache-Control", "no-cache")

lib/ur/failurereporting.go

@@ -214,6 +214,7 @@ func sendFailureReports(ctx context.Context, reports []contract.FailureReport, u
 		return
 	}
 	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("User-Agent", build.UserAgent())
 
 	resp, err := client.Do(req)
 	if err != nil {

lib/ur/usage_report.go

@@ -373,6 +373,7 @@ func (s *Service) sendUsageReport(ctx context.Context) error {
 		return err
 	}
 	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("User-Agent", build.UserAgent())
 	resp, err := client.Do(req)
 	if err != nil {
 		return err