traefik/pkg/server/router/tcp/manager.go
Baptiste Mayelle 2bc3fa7b4b
Reserve priority range for internal routers
Co-authored-by: Romain <rtribotte@users.noreply.github.com>
2024-04-02 17:04:05 +02:00

421 lines
15 KiB
Go

package tcp
import (
"context"
"crypto/tls"
"errors"
"fmt"
"math"
"net/http"
"strings"
"github.com/traefik/traefik/v2/pkg/config/runtime"
"github.com/traefik/traefik/v2/pkg/log"
"github.com/traefik/traefik/v2/pkg/middlewares/snicheck"
httpmuxer "github.com/traefik/traefik/v2/pkg/muxer/http"
tcpmuxer "github.com/traefik/traefik/v2/pkg/muxer/tcp"
"github.com/traefik/traefik/v2/pkg/server/provider"
tcpservice "github.com/traefik/traefik/v2/pkg/server/service/tcp"
"github.com/traefik/traefik/v2/pkg/tcp"
traefiktls "github.com/traefik/traefik/v2/pkg/tls"
)
const maxUserPriority = math.MaxInt - 1000
type middlewareBuilder interface {
BuildChain(ctx context.Context, names []string) *tcp.Chain
}
// NewManager Creates a new Manager.
func NewManager(conf *runtime.Configuration,
serviceManager *tcpservice.Manager,
middlewaresBuilder middlewareBuilder,
httpHandlers map[string]http.Handler,
httpsHandlers map[string]http.Handler,
tlsManager *traefiktls.Manager,
) *Manager {
return &Manager{
serviceManager: serviceManager,
middlewaresBuilder: middlewaresBuilder,
httpHandlers: httpHandlers,
httpsHandlers: httpsHandlers,
tlsManager: tlsManager,
conf: conf,
}
}
// Manager is a route/router manager.
type Manager struct {
serviceManager *tcpservice.Manager
middlewaresBuilder middlewareBuilder
httpHandlers map[string]http.Handler
httpsHandlers map[string]http.Handler
tlsManager *traefiktls.Manager
conf *runtime.Configuration
}
func (m *Manager) getTCPRouters(ctx context.Context, entryPoints []string) map[string]map[string]*runtime.TCPRouterInfo {
if m.conf != nil {
return m.conf.GetTCPRoutersByEntryPoints(ctx, entryPoints)
}
return make(map[string]map[string]*runtime.TCPRouterInfo)
}
func (m *Manager) getHTTPRouters(ctx context.Context, entryPoints []string, tls bool) map[string]map[string]*runtime.RouterInfo {
if m.conf != nil {
return m.conf.GetRoutersByEntryPoints(ctx, entryPoints, tls)
}
return make(map[string]map[string]*runtime.RouterInfo)
}
// BuildHandlers builds the handlers for the given entrypoints.
func (m *Manager) BuildHandlers(rootCtx context.Context, entryPoints []string) map[string]*Router {
entryPointsRouters := m.getTCPRouters(rootCtx, entryPoints)
entryPointsRoutersHTTP := m.getHTTPRouters(rootCtx, entryPoints, true)
entryPointHandlers := make(map[string]*Router)
for _, entryPointName := range entryPoints {
routers := entryPointsRouters[entryPointName]
ctx := log.With(rootCtx, log.Str(log.EntryPointName, entryPointName))
handler, err := m.buildEntryPointHandler(ctx, routers, entryPointsRoutersHTTP[entryPointName], m.httpHandlers[entryPointName], m.httpsHandlers[entryPointName])
if err != nil {
log.FromContext(ctx).Error(err)
continue
}
entryPointHandlers[entryPointName] = handler
}
return entryPointHandlers
}
type nameAndConfig struct {
routerName string // just so we have it as additional information when logging
TLSConfig *tls.Config
}
func (m *Manager) buildEntryPointHandler(ctx context.Context, configs map[string]*runtime.TCPRouterInfo, configsHTTP map[string]*runtime.RouterInfo, handlerHTTP, handlerHTTPS http.Handler) (*Router, error) {
// Build a new Router.
router, err := NewRouter()
if err != nil {
return nil, err
}
router.SetHTTPHandler(handlerHTTP)
// Even though the error is seemingly ignored (aside from logging it),
// we actually rely later on the fact that a tls config is nil (which happens when an error is returned) to take special steps
// when assigning a handler to a route.
defaultTLSConf, err := m.tlsManager.Get(traefiktls.DefaultTLSStoreName, traefiktls.DefaultTLSConfigName)
if err != nil {
log.FromContext(ctx).Errorf("Error during the build of the default TLS configuration: %v", err)
}
// Keyed by domain. The source of truth for doing SNI checking (domain fronting).
// As soon as there's (at least) two different tlsOptions found for the same domain,
// we set the value to the default TLS conf.
tlsOptionsForHost := map[string]string{}
// Keyed by domain, then by options reference.
// The actual source of truth for what TLS options will actually be used for the connection.
// As opposed to tlsOptionsForHost, it keeps track of all the (different) TLS
// options that occur for a given host name, so that later on we can set relevant
// errors and logging for all the routers concerned (i.e. wrongly configured).
tlsOptionsForHostSNI := map[string]map[string]nameAndConfig{}
for routerHTTPName, routerHTTPConfig := range configsHTTP {
if routerHTTPConfig.TLS == nil {
continue
}
ctxRouter := log.With(provider.AddInContext(ctx, routerHTTPName), log.Str(log.RouterName, routerHTTPName))
logger := log.FromContext(ctxRouter)
tlsOptionsName := traefiktls.DefaultTLSConfigName
if len(routerHTTPConfig.TLS.Options) > 0 && routerHTTPConfig.TLS.Options != traefiktls.DefaultTLSConfigName {
tlsOptionsName = provider.GetQualifiedName(ctxRouter, routerHTTPConfig.TLS.Options)
}
domains, err := httpmuxer.ParseDomains(routerHTTPConfig.Rule)
if err != nil {
routerErr := fmt.Errorf("invalid rule %s, error: %w", routerHTTPConfig.Rule, err)
routerHTTPConfig.AddError(routerErr, true)
logger.Error(routerErr)
continue
}
if len(domains) == 0 {
// Extra Host(*) rule, for HTTPS routers with no Host rule,
// and for requests for which the SNI does not match _any_ of the other existing routers Host.
// This is only about choosing the TLS configuration.
// The actual routing will be done further on by the HTTPS handler.
// See examples below.
router.AddHTTPTLSConfig("*", defaultTLSConf)
// The server name (from a Host(SNI) rule) is the only parameter (available in HTTP routing rules) on which we can map a TLS config,
// because it is the only one accessible before decryption (we obtain it during the ClientHello).
// Therefore, when a router has no Host rule, it does not make any sense to specify some TLS options.
// Consequently, when it comes to deciding what TLS config will be used,
// for a request that will match an HTTPS router with no Host rule,
// the result will depend on the _others_ existing routers (their Host rule, to be precise), and the TLS options associated with them,
// even though they don't match the incoming request. Consider the following examples:
// # conf1
// httpRouter1:
// rule: PathPrefix("/foo")
// # Wherever the request comes from, the TLS config used will be the default one, because of the Host(*) fallback.
// # conf2
// httpRouter1:
// rule: PathPrefix("/foo")
//
// httpRouter2:
// rule: Host("foo.com") && PathPrefix("/bar")
// tlsoptions: myTLSOptions
// # When a request for "/foo" comes, even though it won't be routed by httpRouter2,
// # if its SNI is set to foo.com, myTLSOptions will be used for the TLS connection.
// # Otherwise, it will fallback to the default TLS config.
logger.Warnf("No domain found in rule %v, the TLS options applied for this router will depend on the SNI of each request", routerHTTPConfig.Rule)
}
// Even though the error is seemingly ignored (aside from logging it),
// we actually rely later on the fact that a tls config is nil (which happens when an error is returned) to take special steps
// when assigning a handler to a route.
tlsConf, tlsConfErr := m.tlsManager.Get(traefiktls.DefaultTLSStoreName, tlsOptionsName)
if tlsConfErr != nil {
// Note: we do not call AddError here because we already did so when buildRouterHandler errored for the same reason.
logger.Error(tlsConfErr)
}
for _, domain := range domains {
// domain is already in lower case thanks to the domain parsing
if tlsOptionsForHostSNI[domain] == nil {
tlsOptionsForHostSNI[domain] = make(map[string]nameAndConfig)
}
tlsOptionsForHostSNI[domain][tlsOptionsName] = nameAndConfig{
routerName: routerHTTPName,
TLSConfig: tlsConf,
}
if name, ok := tlsOptionsForHost[domain]; ok && name != tlsOptionsName {
// Different tlsOptions on the same domain, so fallback to default
tlsOptionsForHost[domain] = traefiktls.DefaultTLSConfigName
} else {
tlsOptionsForHost[domain] = tlsOptionsName
}
}
}
sniCheck := snicheck.New(tlsOptionsForHost, handlerHTTPS)
// Keep in mind that defaultTLSConf might be nil here.
router.SetHTTPSHandler(sniCheck, defaultTLSConf)
logger := log.FromContext(ctx)
for hostSNI, tlsConfigs := range tlsOptionsForHostSNI {
if len(tlsConfigs) == 1 {
var optionsName string
var config *tls.Config
for k, v := range tlsConfigs {
optionsName = k
config = v.TLSConfig
break
}
if config == nil {
// we use nil config as a signal to insert a handler
// that enforces that TLS connection attempts to the corresponding (broken) router should fail.
logger.Debugf("Adding special closing route for %s because broken TLS options %s", hostSNI, optionsName)
router.AddHTTPTLSConfig(hostSNI, nil)
continue
}
logger.Debugf("Adding route for %s with TLS options %s", hostSNI, optionsName)
router.AddHTTPTLSConfig(hostSNI, config)
continue
}
// multiple tlsConfigs
routers := make([]string, 0, len(tlsConfigs))
for _, v := range tlsConfigs {
configsHTTP[v.routerName].AddError(fmt.Errorf("found different TLS options for routers on the same host %v, so using the default TLS options instead", hostSNI), false)
routers = append(routers, v.routerName)
}
logger.Warnf("Found different TLS options for routers on the same host %v, so using the default TLS options instead for these routers: %#v", hostSNI, routers)
if defaultTLSConf == nil {
logger.Debugf("Adding special closing route for %s because broken default TLS options", hostSNI)
}
router.AddHTTPTLSConfig(hostSNI, defaultTLSConf)
}
m.addTCPHandlers(ctx, configs, router)
return router, nil
}
// addTCPHandlers creates the TCP handlers defined in configs, and adds them to router.
func (m *Manager) addTCPHandlers(ctx context.Context, configs map[string]*runtime.TCPRouterInfo, router *Router) {
for routerName, routerConfig := range configs {
ctxRouter := log.With(provider.AddInContext(ctx, routerName), log.Str(log.RouterName, routerName))
logger := log.FromContext(ctxRouter)
if routerConfig.Service == "" {
err := errors.New("the service is missing on the router")
routerConfig.AddError(err, true)
logger.Error(err)
continue
}
if routerConfig.Rule == "" {
err := errors.New("router has no rule")
routerConfig.AddError(err, true)
logger.Error(err)
continue
}
domains, err := tcpmuxer.ParseHostSNI(routerConfig.Rule)
if err != nil {
routerErr := fmt.Errorf("invalid rule: %q , %w", routerConfig.Rule, err)
routerConfig.AddError(routerErr, true)
logger.Error(routerErr)
continue
}
// HostSNI Rule, but TLS not set on the router, which is an error.
// However, we allow the HostSNI(*) exception.
if len(domains) > 0 && routerConfig.TLS == nil && domains[0] != "*" {
routerErr := fmt.Errorf("invalid rule: %q , has HostSNI matcher, but no TLS on router", routerConfig.Rule)
routerConfig.AddError(routerErr, true)
logger.Error(routerErr)
continue
}
if routerConfig.Priority > maxUserPriority && !strings.HasSuffix(routerName, "@internal") {
routerErr := fmt.Errorf("the router priority %d exceeds the max user-defined priority %d", routerConfig.Priority, maxUserPriority)
routerConfig.AddError(routerErr, true)
logger.Error(routerErr)
continue
}
var handler tcp.Handler
if routerConfig.TLS == nil || routerConfig.TLS.Passthrough {
handler, err = m.buildTCPHandler(ctxRouter, routerConfig)
if err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
continue
}
}
if routerConfig.TLS == nil {
logger.Debugf("Adding route for %q", routerConfig.Rule)
if err := router.AddRoute(routerConfig.Rule, routerConfig.Priority, handler); err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
}
continue
}
if routerConfig.TLS.Passthrough {
logger.Debugf("Adding Passthrough route for %q", routerConfig.Rule)
if err := router.muxerTCPTLS.AddRoute(routerConfig.Rule, routerConfig.Priority, handler); err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
}
continue
}
for _, domain := range domains {
if httpmuxer.IsASCII(domain) {
continue
}
asciiError := fmt.Errorf("invalid domain name value %q, non-ASCII characters are not allowed", domain)
routerConfig.AddError(asciiError, true)
logger.Error(asciiError)
}
tlsOptionsName := routerConfig.TLS.Options
if len(tlsOptionsName) == 0 {
tlsOptionsName = traefiktls.DefaultTLSConfigName
}
if tlsOptionsName != traefiktls.DefaultTLSConfigName {
tlsOptionsName = provider.GetQualifiedName(ctxRouter, tlsOptionsName)
}
tlsConf, err := m.tlsManager.Get(traefiktls.DefaultTLSStoreName, tlsOptionsName)
if err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
logger.Debugf("Adding special TLS closing route for %q because broken TLS options %s", routerConfig.Rule, tlsOptionsName)
err = router.muxerTCPTLS.AddRoute(routerConfig.Rule, routerConfig.Priority, &brokenTLSRouter{})
if err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
}
continue
}
// Now that the Rule is not just about the Host, we could theoretically have a config like:
// router1:
// rule: HostSNI(foo.com) && ClientIP(IP1)
// tlsOption: tlsOne
// router2:
// rule: HostSNI(foo.com) && ClientIP(IP2)
// tlsOption: tlsTwo
// i.e. same HostSNI but different tlsOptions
// This is only applicable if the muxer can decide about the routing _before_ telling the client about the tlsConf (i.e. before the TLS HandShake).
// This seems to be the case so far with the existing matchers (HostSNI, and ClientIP), so it's all good.
// Otherwise, we would have to do as for HTTPS, i.e. disallow different TLS configs for the same HostSNIs.
handler, err = m.buildTCPHandler(ctxRouter, routerConfig)
if err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
continue
}
handler = &tcp.TLSHandler{
Next: handler,
Config: tlsConf,
}
logger.Debugf("Adding TLS route for %q", routerConfig.Rule)
err = router.muxerTCPTLS.AddRoute(routerConfig.Rule, routerConfig.Priority, handler)
if err != nil {
routerConfig.AddError(err, true)
logger.Error(err)
}
}
}
func (m *Manager) buildTCPHandler(ctx context.Context, router *runtime.TCPRouterInfo) (tcp.Handler, error) {
var qualifiedNames []string
for _, name := range router.Middlewares {
qualifiedNames = append(qualifiedNames, provider.GetQualifiedName(ctx, name))
}
router.Middlewares = qualifiedNames
if router.Service == "" {
return nil, errors.New("the service is missing on the router")
}
sHandler, err := m.serviceManager.BuildTCP(ctx, router.Service)
if err != nil {
return nil, err
}
mHandler := m.middlewaresBuilder.BuildChain(ctx, router.Middlewares)
return tcp.NewChain().Extend(*mHandler).Then(sHandler)
}