improve certificate matching performance (#4188)

improve certificate matching performance (#4186)

Co-authored-by: Caleb Doxsey <cdoxsey@pomerium.com>

config/config.go

@@ -12,7 +12,6 @@ import (
 	"github.com/pomerium/pomerium/internal/fileutil"
 	"github.com/pomerium/pomerium/internal/hashutil"
 	"github.com/pomerium/pomerium/internal/httputil"
-	"github.com/pomerium/pomerium/internal/log"
 	"github.com/pomerium/pomerium/internal/telemetry/metrics"
 	"github.com/pomerium/pomerium/internal/urlutil"
 	"github.com/pomerium/pomerium/pkg/cryptutil"
@@ -149,24 +148,9 @@ func (cfg *Config) GetTLSClientConfig() (*tls.Config, error) {
 	}, nil
 }
 
-// GetCertificateForServerName gets the certificate for the server name. If no certificate is found and there
-// is a derived CA one will be generated using that CA. If no derived CA is defined a self-signed certificate
-// will be generated.
-func (cfg *Config) GetCertificateForServerName(serverName string) (*tls.Certificate, error) {
-	certificates, err := cfg.AllCertificates()
-	if err != nil {
-		return nil, err
-	}
-
-	// first try a direct name match
-	for i := range certificates {
-		if cryptutil.MatchesServerName(&certificates[i], serverName) {
-			return &certificates[i], nil
-		}
-	}
-
-	log.WarnNoTLSCertificate(serverName)
-
+// GenerateCatchAllCertificate generates a catch-all certificate. If no derived CA is defined a
+// self-signed certificate will be generated.
+func (cfg *Config) GenerateCatchAllCertificate() (*tls.Certificate, error) {
 	if cfg.Options.DeriveInternalDomainCert != nil {
 		sharedKey, err := cfg.Options.GetSharedKey()
 		if err != nil {
@@ -178,7 +162,7 @@ func (cfg *Config) GetCertificateForServerName(serverName string) (*tls.Certific
 			return nil, fmt.Errorf("failed to generate cert, invalid derived CA: %w", err)
 		}
 
-		pem, err := ca.NewServerCert([]string{serverName})
+		pem, err := ca.NewServerCert([]string{"*"})
 		if err != nil {
 			return nil, fmt.Errorf("failed to generate cert, error creating server certificate: %w", err)
 		}
@@ -196,7 +180,7 @@ func (cfg *Config) GetCertificateForServerName(serverName string) (*tls.Certific
 	}
 
 	// finally fall back to a generated, self-signed certificate
-	return cryptutil.GenerateCertificate(sharedKey, serverName)
+	return cryptutil.GenerateCertificate(sharedKey, "*")
 }
 
 // WillHaveCertificateForServerName returns true if there will be a certificate for the given server name.

config/envoyconfig/listeners.go

@@ -109,7 +109,8 @@ func getAllCertificates(cfg *config.Config) ([]tls.Certificate, error) {
 	if err != nil {
 		return nil, fmt.Errorf("error collecting all certificates: %w", err)
 	}
-	wc, err := cfg.GetCertificateForServerName("*")
+
+	wc, err := cfg.GenerateCatchAllCertificate()
 	if err != nil {
 		return nil, fmt.Errorf("error getting wildcard certificate: %w", err)
 	}

config/envoyconfig/route_configurations.go

@@ -78,7 +78,7 @@ func (b *Builder) buildMainRouteConfiguration(
 
 		// if we're the proxy, add all the policy routes
 		if config.IsProxy(cfg.Options.Services) {
-			rs, err := b.buildRoutesForPoliciesWithHost(cfg, host)
+			rs, err := b.buildRoutesForPoliciesWithHost(cfg, certs, host)
 			if err != nil {
 				return nil, err
 			}
@@ -95,7 +95,7 @@ func (b *Builder) buildMainRouteConfiguration(
 		return nil, err
 	}
 	if config.IsProxy(cfg.Options.Services) {
-		rs, err := b.buildRoutesForPoliciesWithCatchAll(cfg)
+		rs, err := b.buildRoutesForPoliciesWithCatchAll(cfg, certs)
 		if err != nil {
 			return nil, err
 		}

config/envoyconfig/routes.go

@@ -1,6 +1,7 @@
 package envoyconfig
 
 import (
+	"crypto/tls"
 	"encoding/json"
 	"fmt"
 	"net/url"
@@ -193,6 +194,7 @@ func getClusterStatsName(policy *config.Policy) string {
 
 func (b *Builder) buildRoutesForPoliciesWithHost(
 	cfg *config.Config,
+	certs []tls.Certificate,
 	host string,
 ) ([]*envoy_config_route_v3.Route, error) {
 	var routes []*envoy_config_route_v3.Route
@@ -207,7 +209,7 @@ func (b *Builder) buildRoutesForPoliciesWithHost(
 			continue
 		}
 
-		policyRoutes, err := b.buildRoutesForPolicy(cfg, &policy, fmt.Sprintf("policy-%d", i))
+		policyRoutes, err := b.buildRoutesForPolicy(cfg, certs, &policy, fmt.Sprintf("policy-%d", i))
 		if err != nil {
 			return nil, err
 		}
@@ -219,6 +221,7 @@ func (b *Builder) buildRoutesForPoliciesWithHost(
 
 func (b *Builder) buildRoutesForPoliciesWithCatchAll(
 	cfg *config.Config,
+	certs []tls.Certificate,
 ) ([]*envoy_config_route_v3.Route, error) {
 	var routes []*envoy_config_route_v3.Route
 	for i, p := range cfg.Options.GetAllPolicies() {
@@ -232,7 +235,7 @@ func (b *Builder) buildRoutesForPoliciesWithCatchAll(
 			continue
 		}
 
-		policyRoutes, err := b.buildRoutesForPolicy(cfg, &policy, fmt.Sprintf("policy-%d", i))
+		policyRoutes, err := b.buildRoutesForPolicy(cfg, certs, &policy, fmt.Sprintf("policy-%d", i))
 		if err != nil {
 			return nil, err
 		}
@@ -244,6 +247,7 @@ func (b *Builder) buildRoutesForPoliciesWithCatchAll(
 
 func (b *Builder) buildRoutesForPolicy(
 	cfg *config.Config,
+	certs []tls.Certificate,
 	policy *config.Policy,
 	name string,
 ) ([]*envoy_config_route_v3.Route, error) {
@@ -256,14 +260,14 @@ func (b *Builder) buildRoutesForPolicy(
 	if strings.Contains(fromURL.Host, "*") {
 		// we have to match '*.example.com' and '*.example.com:443', so there are two routes
 		for _, host := range urlutil.GetDomainsForURL(fromURL) {
-			route, err := b.buildRouteForPolicyAndMatch(cfg, policy, name, mkRouteMatchForHost(policy, host))
+			route, err := b.buildRouteForPolicyAndMatch(cfg, certs, policy, name, mkRouteMatchForHost(policy, host))
 			if err != nil {
 				return nil, err
 			}
 			routes = append(routes, route)
 		}
 	} else {
-		route, err := b.buildRouteForPolicyAndMatch(cfg, policy, name, mkRouteMatch(policy))
+		route, err := b.buildRouteForPolicyAndMatch(cfg, certs, policy, name, mkRouteMatch(policy))
 		if err != nil {
 			return nil, err
 		}
@@ -274,6 +278,7 @@ func (b *Builder) buildRoutesForPolicy(
 
 func (b *Builder) buildRouteForPolicyAndMatch(
 	cfg *config.Config,
+	certs []tls.Certificate,
 	policy *config.Policy,
 	name string,
 	match *envoy_config_route_v3.RouteMatch,
@@ -283,11 +288,6 @@ func (b *Builder) buildRouteForPolicyAndMatch(
 		return nil, err
 	}
 
-	certs, err := getAllCertificates(cfg)
-	if err != nil {
-		return nil, err
-	}
-
 	requireStrictTransportSecurity := cryptutil.HasCertificateForServerName(certs, fromURL.Hostname())
 
 	route := &envoy_config_route_v3.Route{

config/envoyconfig/routes_test.go

@@ -307,7 +307,7 @@ func TestTimeouts(t *testing.T) {
 					AllowWebsockets: tc.allowWebsockets,
 				},
 			},
-		}}, "example.com")
+		}}, nil, "example.com")
 		if !assert.NoError(t, err, "%v", tc) || !assert.Len(t, routes, 1, tc) || !assert.NotNil(t, routes[0].GetRoute(), "%v", tc) {
 			continue
 		}
@@ -412,7 +412,7 @@ func Test_buildPolicyRoutes(t *testing.T) {
 				UpstreamTimeout:     &ten,
 			},
 		},
-	}}, "example.com")
+	}}, nil, "example.com")
 	require.NoError(t, err)
 
 	testutil.AssertProtoJSONEqual(t, `
@@ -918,7 +918,7 @@ func Test_buildPolicyRoutes(t *testing.T) {
 					PassIdentityHeaders: true,
 				},
 			},
-		}}, "authenticate.example.com")
+		}}, nil, "authenticate.example.com")
 		require.NoError(t, err)
 
 		testutil.AssertProtoJSONEqual(t, `
@@ -1005,7 +1005,7 @@ func Test_buildPolicyRoutes(t *testing.T) {
 					UpstreamTimeout:     &ten,
 				},
 			},
-		}}, "example.com:22")
+		}}, nil, "example.com:22")
 		require.NoError(t, err)
 
 		testutil.AssertProtoJSONEqual(t, `
@@ -1151,7 +1151,7 @@ func Test_buildPolicyRoutes(t *testing.T) {
 					From: "https://from.example.com",
 				},
 			},
-		}}, "from.example.com")
+		}}, nil, "from.example.com")
 		require.NoError(t, err)
 
 		testutil.AssertProtoJSONEqual(t, `
@@ -1272,7 +1272,7 @@ func Test_buildPolicyRoutesRewrite(t *testing.T) {
 				HostPathRegexRewriteSubstitution: "\\1",
 			},
 		},
-	}}, "example.com")
+	}}, nil, "example.com")
 	require.NoError(t, err)
 
 	testutil.AssertProtoJSONEqual(t, `