pomerium/internal/zero/healthcheck/check_routes.go
Joe Kralicky 332932b7a8
Replace usages of x/exp/maps + bump golang.org/x/exp (#5221)
Bump golang.org/x/exp; replace usages of x/exp/maps with stdlib equivalents
2024-08-15 17:49:24 -04:00

122 lines
3.2 KiB
Go

package healthcheck
import (
"context"
"crypto/tls"
"encoding/base64"
"errors"
"fmt"
"maps"
"net"
"net/http"
"slices"
"time"
"github.com/go-jose/go-jose/v3"
"github.com/pomerium/pomerium/config"
"github.com/pomerium/pomerium/internal/urlutil"
"github.com/pomerium/pomerium/pkg/cryptutil"
configpb "github.com/pomerium/pomerium/pkg/grpc/config"
"github.com/pomerium/pomerium/pkg/health"
clusterping "github.com/pomerium/pomerium/pkg/zero/ping"
)
// CheckRoutes checks whether all routes that are referenced by this pomerium instance configuration are reachable
// it resolves the DNS entry and tries to access a pomerium jwks route
// we should hit ourselves and observe the same public key that we have in our configuration
// otherwise, something is misconfigured on the DNS level
func (c *checker) CheckRoutes(ctx context.Context) error {
key, err := getClusterPublicKey(c.bootstrap.GetConfig())
if err != nil {
health.ReportInternalError(health.RoutesReachable, err)
return err
}
err = checkRoutesReachable(ctx, key, c.GetConfigs())
if err == nil {
health.ReportOK(health.RoutesReachable)
} else if ctx.Err() == nil {
health.ReportError(health.RoutesReachable, err)
}
return err
}
const (
connectionTimeout = time.Second * 30
)
func getPingHTTPClient() *http.Client {
return &http.Client{
Timeout: connectionTimeout,
Transport: &http.Transport{
TLSClientConfig: &tls.Config{
InsecureSkipVerify: true,
},
DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
return (&net.Dialer{
Timeout: connectionTimeout,
}).DialContext(ctx, network, addr)
},
},
}
}
func checkRoutesReachable(
ctx context.Context,
key *jose.JSONWebKey,
configs []*configpb.Config,
) error {
hosts, err := getHosts(configs)
if err != nil {
return fmt.Errorf("error getting route hosts: %w", err)
}
client := getPingHTTPClient()
var errs []error
for _, host := range hosts {
err = clusterping.CheckKey(ctx, clusterping.GetJWKSURL(host), *key, client)
if err != nil {
errs = append(errs, fmt.Errorf("%s: %w", host, err))
}
}
return errors.Join(errs...)
}
func getClusterPublicKey(cfg *config.Config) (*jose.JSONWebKey, error) {
data, err := base64.StdEncoding.DecodeString(cfg.Options.SigningKey)
if err != nil {
return nil, fmt.Errorf("error decoding signing key: %w", err)
}
key, err := cryptutil.PublicJWKFromBytes(data)
if err != nil {
return nil, fmt.Errorf("error creating public jwk from bytes: %w", err)
}
return key, nil
}
func getHosts(configs []*configpb.Config) ([]string, error) {
hosts := make(map[string]struct{})
for _, cfg := range configs {
for _, route := range cfg.GetRoutes() {
if route.GetTlsCustomCa() != "" {
continue
}
u, err := urlutil.ParseAndValidateURL(route.GetFrom())
if err != nil {
continue
}
if u.Scheme != "https" {
// there's a complication with TCP+HTTPS routes as in general we may not know the host address for them
// and we can't rely on the config's server address port part, as it may be different from actual externally reachable port
continue
}
hosts[u.Host] = struct{}{}
}
}
return slices.Sorted(maps.Keys(hosts)), nil
}