authenticate: support webauthn redirects to non-pomerium domains (#2936)

* authenticate: support webauthn redirects to non-pomerium domains

* add test

* remove dead code

authenticate/handlers.go

@@ -686,9 +686,15 @@ func (a *Authenticate) getWebauthnState(ctx context.Context) (*webauthn.State, e
 		return nil, err
 	}
 
+	pomeriumDomains, err := a.options.Load().GetAllRouteableHTTPDomains()
+	if err != nil {
+		return nil, err
+	}
+
 	return &webauthn.State{
 		SharedKey:       state.sharedKey,
 		Client:          state.dataBrokerClient,
+		PomeriumDomains: pomeriumDomains,
 		Session:         s,
 		SessionState:    ss,
 		SessionStore:    state.sessionStore,

authenticate/handlers/webauthn/webauthn.go

@@ -52,6 +52,7 @@ var (
 type State struct {
 	SharedKey       []byte
 	Client          databroker.DataBrokerServiceClient
+	PomeriumDomains []string
 	Session         *session.Session
 	SessionState    *sessions.State
 	SessionStore    sessions.SessionStore
@@ -392,6 +393,12 @@ func (h *Handler) handleView(w http.ResponseWriter, r *http.Request, state *Stat
 }
 
 func (h *Handler) saveSessionAndRedirect(w http.ResponseWriter, r *http.Request, state *State, rawRedirectURI string) error {
+	// if the redirect URL is for a URL we don't control, just do a plain redirect
+	if !isURLForPomerium(state.PomeriumDomains, rawRedirectURI) {
+		httputil.Redirect(w, r, rawRedirectURI, http.StatusFound)
+		return nil
+	}
+
 	// save the session to the databroker
 	res, err := session.Put(r.Context(), state.Client, state.Session)
 	if err != nil {
@@ -513,3 +520,18 @@ func getOrCreateDeviceEnrollment(
 	}
 	return deviceEnrollment, nil
 }
+
+func isURLForPomerium(pomeriumDomains []string, rawURI string) bool {
+	uri, err := urlutil.ParseAndValidateURL(rawURI)
+	if err != nil {
+		return false
+	}
+
+	for _, domain := range pomeriumDomains {
+		if urlutil.StripPort(domain) == urlutil.StripPort(uri.Host) {
+			return true
+		}
+	}
+
+	return false
+}

config/envoyconfig/listeners.go

@@ -734,89 +734,15 @@ func getRouteableDomainsForTLSDomain(options *config.Options, addr string, tlsDo
 }
 
 func getAllRouteableDomains(options *config.Options, addr string) ([]string, error) {
-	forwardAuthURL, err := options.GetForwardAuthURL()
-	if err != nil {
-		return nil, err
+	switch addr {
+	case options.Addr:
+		return options.GetAllRouteableHTTPDomains()
+	case options.GetGRPCAddr():
+		return options.GetAllRouteableGRPCDomains()
 	}
 
-	lookup := map[string]struct{}{}
-	if config.IsAuthenticate(options.Services) && addr == options.Addr {
-		authenticateURL, err := options.GetInternalAuthenticateURL()
-		if err != nil {
-			return nil, err
-		}
-		for _, h := range urlutil.GetDomainsForURL(*authenticateURL) {
-			lookup[h] = struct{}{}
-		}
-	}
-
-	// authorize urls
-	if config.IsAll(options.Services) && addr == options.GetGRPCAddr() {
-		authorizeURLs, err := options.GetAuthorizeURLs()
-		if err != nil {
-			return nil, err
-		}
-		for _, u := range authorizeURLs {
-			for _, h := range urlutil.GetDomainsForURL(*u) {
-				lookup[h] = struct{}{}
-			}
-		}
-	} else if config.IsAuthorize(options.Services) && addr == options.GetGRPCAddr() {
-		authorizeURLs, err := options.GetInternalAuthorizeURLs()
-		if err != nil {
-			return nil, err
-		}
-		for _, u := range authorizeURLs {
-			for _, h := range urlutil.GetDomainsForURL(*u) {
-				lookup[h] = struct{}{}
-			}
-		}
-	}
-
-	// databroker urls
-	if config.IsAll(options.Services) && addr == options.GetGRPCAddr() {
-		dataBrokerURLs, err := options.GetDataBrokerURLs()
-		if err != nil {
-			return nil, err
-		}
-		for _, u := range dataBrokerURLs {
-			for _, h := range urlutil.GetDomainsForURL(*u) {
-				lookup[h] = struct{}{}
-			}
-		}
-	} else if config.IsDataBroker(options.Services) && addr == options.GetGRPCAddr() {
-		dataBrokerURLs, err := options.GetInternalDataBrokerURLs()
-		if err != nil {
-			return nil, err
-		}
-		for _, u := range dataBrokerURLs {
-			for _, h := range urlutil.GetDomainsForURL(*u) {
-				lookup[h] = struct{}{}
-			}
-		}
-	}
-
-	// policy urls
-	if config.IsProxy(options.Services) && addr == options.Addr {
-		for _, policy := range options.GetAllPolicies() {
-			for _, h := range urlutil.GetDomainsForURL(*policy.Source.URL) {
-				lookup[h] = struct{}{}
-			}
-		}
-		if forwardAuthURL != nil {
-			for _, h := range urlutil.GetDomainsForURL(*forwardAuthURL) {
-				lookup[h] = struct{}{}
-			}
-		}
-	}
-
-	domains := make([]string, 0, len(lookup))
-	for domain := range lookup {
-		domains = append(domains, domain)
-	}
-	sort.Strings(domains)
-
-	return domains, nil
+	// no other domains supported
+	return nil, nil
 }
 
 func getAllTLSDomains(options *config.Options, addr string) ([]string, error) {

config/options.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"sort"
 	"strings"
 	"sync/atomic"
 	"time"
@@ -1041,6 +1042,106 @@ func (o *Options) GetCodecType() CodecType {
 	return o.CodecType
 }
 
+// GetAllRouteableGRPCDomains returns all the possible gRPC domains handled by the Pomerium options.
+func (o *Options) GetAllRouteableGRPCDomains() ([]string, error) {
+	lookup := map[string]struct{}{}
+
+	// authorize urls
+	if IsAll(o.Services) {
+		authorizeURLs, err := o.GetAuthorizeURLs()
+		if err != nil {
+			return nil, err
+		}
+		for _, u := range authorizeURLs {
+			for _, h := range urlutil.GetDomainsForURL(*u) {
+				lookup[h] = struct{}{}
+			}
+		}
+	} else if IsAuthorize(o.Services) {
+		authorizeURLs, err := o.GetInternalAuthorizeURLs()
+		if err != nil {
+			return nil, err
+		}
+		for _, u := range authorizeURLs {
+			for _, h := range urlutil.GetDomainsForURL(*u) {
+				lookup[h] = struct{}{}
+			}
+		}
+	}
+
+	// databroker urls
+	if IsAll(o.Services) {
+		dataBrokerURLs, err := o.GetDataBrokerURLs()
+		if err != nil {
+			return nil, err
+		}
+		for _, u := range dataBrokerURLs {
+			for _, h := range urlutil.GetDomainsForURL(*u) {
+				lookup[h] = struct{}{}
+			}
+		}
+	} else if IsDataBroker(o.Services) {
+		dataBrokerURLs, err := o.GetInternalDataBrokerURLs()
+		if err != nil {
+			return nil, err
+		}
+		for _, u := range dataBrokerURLs {
+			for _, h := range urlutil.GetDomainsForURL(*u) {
+				lookup[h] = struct{}{}
+			}
+		}
+	}
+
+	domains := make([]string, 0, len(lookup))
+	for domain := range lookup {
+		domains = append(domains, domain)
+	}
+	sort.Strings(domains)
+
+	return domains, nil
+}
+
+// GetAllRouteableHTTPDomains returns all the possible HTTP domains handled by the Pomerium options.
+func (o *Options) GetAllRouteableHTTPDomains() ([]string, error) {
+	forwardAuthURL, err := o.GetForwardAuthURL()
+	if err != nil {
+		return nil, err
+	}
+
+	lookup := map[string]struct{}{}
+	if IsAuthenticate(o.Services) {
+		authenticateURL, err := o.GetInternalAuthenticateURL()
+		if err != nil {
+			return nil, err
+		}
+		for _, h := range urlutil.GetDomainsForURL(*authenticateURL) {
+			lookup[h] = struct{}{}
+		}
+	}
+
+	// policy urls
+	if IsProxy(o.Services) {
+		for _, policy := range o.GetAllPolicies() {
+			for _, h := range urlutil.GetDomainsForURL(*policy.Source.URL) {
+				lookup[h] = struct{}{}
+			}
+		}
+		if forwardAuthURL != nil {
+			for _, h := range urlutil.GetDomainsForURL(*forwardAuthURL) {
+				lookup[h] = struct{}{}
+			}
+		}
+	}
+
+	domains := make([]string, 0, len(lookup))
+	for domain := range lookup {
+		domains = append(domains, domain)
+	}
+	sort.Strings(domains)
+
+	return domains, nil
+}
+
 // Checksum returns the checksum of the current options struct
 func (o *Options) Checksum() uint64 {
 	return hashutil.MustHash(o)

config/options_test.go

@@ -684,6 +684,49 @@ func TestOptions_GetOauthOptions(t *testing.T) {
 	require.NoError(t, err)
 	assert.Equal(t, u.Hostname(), oauthOptions.RedirectURL.Hostname())
 }
+func TestOptions_GetAllRouteableGRPCDomains(t *testing.T) {
+	opts := &Options{
+		AuthenticateURLString: "https://authenticate.example.com",
+		AuthorizeURLString:    "https://authorize.example.com",
+		DataBrokerURLString:   "https://databroker.example.com",
+		Services:              "all",
+	}
+	domains, err := opts.GetAllRouteableGRPCDomains()
+	assert.NoError(t, err)
+
+	assert.Equal(t, []string{
+		"authorize.example.com",
+		"authorize.example.com:443",
+		"databroker.example.com",
+		"databroker.example.com:443",
+	}, domains)
+}
+
+func TestOptions_GetAllRouteableHTTPDomains(t *testing.T) {
+	p1 := Policy{From: "https://from1.example.com"}
+	p1.Validate()
+	p2 := Policy{From: "https://from2.example.com"}
+	p2.Validate()
+
+	opts := &Options{
+		AuthenticateURLString: "https://authenticate.example.com",
+		AuthorizeURLString:    "https://authorize.example.com",
+		DataBrokerURLString:   "https://databroker.example.com",
+		Policies:              []Policy{p1, p2},
+		Services:              "all",
+	}
+	domains, err := opts.GetAllRouteableHTTPDomains()
+	assert.NoError(t, err)
+
+	assert.Equal(t, []string{
+		"authenticate.example.com",
+		"authenticate.example.com:443",
+		"from1.example.com",
+		"from1.example.com:443",
+		"from2.example.com",
+		"from2.example.com:443",
+	}, domains)
+}
 
 func mustParseWeightedURLs(t *testing.T, urls ...string) []WeightedURL {
 	wu, err := ParseWeightedUrls(urls...)