command/serve.go

@@ -12,6 +12,7 @@ import (
 	"golang.org/x/sync/errgroup"
 	"net"
 	"net/http"
+	"net/http/httputil"
 	"net/netip"
 	"net/url"
 	"regexp"
@@ -33,6 +34,11 @@ type addrPorts struct {
 // methodRegex maps HTTP methods (GET, POST, DELETE...) to a compiled regular expression.
 type methodRegex = map[string]*regexp.Regexp
 
+// ProxyHandlerOld takes an incoming request and sends it to another server, proxying the response back to the client.
+type ProxyHandlerOld struct {
+	rp *httputil.ReverseProxy
+}
+
 // ProxyHandler takes an incoming request and sends it to another server, proxying the response back to the client.
 type ProxyHandler struct {
 	frp *fastrp.FastRP
@@ -75,8 +81,8 @@ const (
 	defaultHealthEndpoint = "/healthz"
 	// defaultHealthListenAddr is the proxy health endpoint default listen address and port.
 	defaultHealthListenAddr = "127.0.0.1:5732"
-	// defaultAllowedRequests is the default allowed requests. Note that they should be sufficient to make Traefik work properly.
+	// defaultAllowedRequest is the proxy default allowed request.
-	defaultAllowedRequests = "/v1.\\d{1,2}/(version|containers/(?:json|[a-zA-Z0-9]{64}/json)|events)$"
+	defaultAllowedRequest = "^/(version|containers/.*|events.*)$"
 )
 
 var s serve
@@ -84,7 +90,7 @@ var s serve
 var (
 	containerMethodRegex = map[string]methodRegex{
 		"*": {
-			http.MethodGet: regexp.MustCompile(defaultAllowedRequests),
+			http.MethodGet: regexp.MustCompile(defaultAllowedRequest),
 		},
 	}
 	applicatorURLRegex = regexp.MustCompile(`^([a-zA-Z0-9][a-zA-Z0-9_.-]+)\(((?:(?:GET|HEAD|POST|PUT|PATCH|DELETE|CONNECT|TRACE|OPTIONS)(?:,(?:GET|HEAD|POST|PUT|PATCH|DELETE|CONNECT|TRACE|OPTIONS))*)?)\):(.*)$`)
@@ -155,6 +161,44 @@ func (ph *ProxyHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	http.Error(w, http.StatusText(http.StatusUnauthorized), http.StatusUnauthorized)
 }
 
+func (ph *ProxyHandlerOld) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	log.Debug().Str("remote_addr", r.RemoteAddr).Str("method", r.Method).Str("path", r.URL.Path).Msg("incoming request")
+	if mr, ok := containerMethodRegex["*"]; ok {
+		if code := ph.checkMethodAndRegex(mr, r, ""); code != http.StatusOK {
+			http.Error(w, http.StatusText(code), code)
+			return
+		}
+		ph.rp.ServeHTTP(w, r)
+		return
+	}
+	host, _, _ := net.SplitHostPort(r.RemoteAddr)
+	for containerName, mr := range containerMethodRegex {
+		if ph.isContainerAuthorized(containerName, host) {
+			if code := ph.checkMethodAndRegex(mr, r, containerName); code != http.StatusOK {
+				http.Error(w, http.StatusText(code), code)
+				return
+			}
+			ph.rp.ServeHTTP(w, r)
+			return
+		}
+	}
+	logDeniedRequest(r, http.StatusUnauthorized, "this container is not on the list of authorized ones")
+	http.Error(w, http.StatusText(http.StatusUnauthorized), http.StatusUnauthorized)
+}
+
+func (ph *ProxyHandlerOld) isContainerAuthorized(containerName, host string) bool {
+	resolvedIPs, err := net.LookupIP(containerName)
+	if err != nil {
+		return false
+	}
+	for resolvedIP := range slices.Values(resolvedIPs) {
+		if resolvedIP.Equal(net.ParseIP(host)) {
+			return true
+		}
+	}
+	return false
+}
+
 func (ph *ProxyHandler) isContainerAuthorized(containerName, host string) bool {
 	resolvedIPs, err := net.LookupIP(containerName)
 	if err != nil {
@@ -188,6 +232,20 @@ func logAuthorizedRequest(r *http.Request, containerName, message string) {
 	l.Msg(message)
 }
 
+func (ph *ProxyHandlerOld) checkMethodAndRegex(mr methodRegex, r *http.Request, containerName string) int {
+	req, ok := mr[r.Method]
+	if !ok {
+		logDeniedRequest(r, http.StatusMethodNotAllowed, "this HTTP method is not in the list of those authorized for this container")
+		return http.StatusMethodNotAllowed
+	}
+	if !req.MatchString(r.URL.Path) {
+		logDeniedRequest(r, http.StatusForbidden, "this path does not match any regular expression for this HTTP method")
+		return http.StatusForbidden
+	}
+	logAuthorizedRequest(r, containerName, "incoming request matches a registered regular expression")
+	return http.StatusOK
+}
+
 func (ph *ProxyHandler) checkMethodAndRegex(mr methodRegex, r *http.Request, containerName string) int {
 	req, ok := mr[r.Method]
 	if !ok {
@@ -217,11 +275,23 @@ func (s serve) action(ctx context.Context, command *cli.Command) error {
 		return err
 	}
 	dummyURL, _ := url.Parse("http://dummy")
+
+	// Old
+	// rp := httputil.NewSingleHostReverseProxy(dummyURL)
+	// rp.Transport = &http.Transport{
+	// 	DialContext: func(_ context.Context, _ string, _ string) (net.Conn, error) {
+	// 		return net.Dial("unix", command.String(dockerSocketPathFlagName))
+	// 	},
+	// }
+
+	// New
+	rp := fastrp.NewRP("unix", command.String(dockerSocketPathFlagName), dummyURL)
+
 	srv := &http.Server{ // #nosec: G112
-		Handler: &ProxyHandler{
+		// Handler: &ProxyHandlerOld{rp: rp},
-			frp: fastrp.NewRP("unix", command.String(dockerSocketPathFlagName), dummyURL),
+		Handler: &ProxyHandler{frp: rp},
-		},
 	}
+
 	s.group.Go(func() error {
 		if err = srv.Serve(l); err != nil && !errors.Is(err, http.ErrServerClosed) {
 			return err
@@ -419,7 +489,7 @@ func addRequests() cli.Flag {
 		Usage:    "add requests",
 		Sources:  middleman.PluckEnvVar(EnvVarPrefix, addRequestsFlagName),
 		// Local:    true, // Required to trigger the Action when this flag is set via the environment variable, see https://github.com/urfave/cli/issues/2041.
-		Value:   []string{"*:" + defaultAllowedRequests},
+		Value:   []string{"*:" + defaultAllowedRequest},
 		Aliases: middleman.PluckAlias(ServeCmd, addRequestsFlagName),
 		Action: func(ctx context.Context, command *cli.Command, requests []string) error {
 			clear(containerMethodRegex)

pkg/fastrp/fastrp.go

@@ -9,6 +9,7 @@ import (
 	"sync"
 )
 
+// FastRP takes an incoming request and sends it fast to another server, proxying the response back to the client fast.
 type FastRP struct {
 	rp       *httputil.ReverseProxy
 	connPool *sync.Pool