simplify setup process

agent/pkg/handler/handler.go

@@ -1,14 +1,21 @@
 package handler
 
 import (
+	"crypto/tls"
+	"encoding/pem"
 	"fmt"
 	"io"
 	"net/http"
 
 	"github.com/yusing/go-proxy/agent/pkg/agent"
+	"github.com/yusing/go-proxy/agent/pkg/certs"
 	"github.com/yusing/go-proxy/agent/pkg/env"
 	v1 "github.com/yusing/go-proxy/internal/api/v1"
+	"github.com/yusing/go-proxy/internal/api/v1/utils"
+	E "github.com/yusing/go-proxy/internal/error"
+	"github.com/yusing/go-proxy/internal/logging"
 	"github.com/yusing/go-proxy/internal/logging/memlogger"
+	"github.com/yusing/go-proxy/internal/task"
 	"github.com/yusing/go-proxy/internal/utils/strutils"
 )
 
@@ -32,7 +39,7 @@ func (NopWriteCloser) Close() error {
 	return nil
 }
 
-func NewHandler() http.Handler {
+func NewAgentHandler() http.Handler {
 	mux := ServeMux{http.NewServeMux()}
 
 	mux.HandleFunc(agent.EndpointProxyHTTP+"/{path...}", ProxyHTTP)
@@ -46,3 +53,46 @@ func NewHandler() http.Handler {
 	mux.ServeMux.HandleFunc("/", DockerSocketHandler())
 	return mux
 }
+
+// NewRegistrationHandler creates a new registration handler
+// It checks if the request is coming from an allowed host
+// Generates a new client certificate and zips it
+// Sends the zipped certificate to the client
+// its run only once on agent first start.
+func NewRegistrationHandler(task *task.Task, ca *tls.Certificate) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if !env.IsAllowedHost(r.RemoteAddr) {
+			http.Error(w, "Unauthorized", http.StatusUnauthorized)
+			return
+		}
+
+		if r.URL.Path == "/done" {
+			logging.Info().Msg("registration done")
+			task.Finish(nil)
+			w.WriteHeader(http.StatusOK)
+			return
+		}
+
+		logging.Info().Msgf("received registration request from %s", r.RemoteAddr)
+
+		caPEM := pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: ca.Certificate[0]})
+
+		crt, key, err := certs.NewClientCert(ca)
+		if err != nil {
+			utils.HandleErr(w, r, E.Wrap(err, "failed to generate client certificate"))
+			return
+		}
+
+		zipped, err := certs.ZipCert(caPEM, crt, key)
+		if err != nil {
+			utils.HandleErr(w, r, E.Wrap(err, "failed to zip certificate"))
+			return
+		}
+
+		w.Header().Set("Content-Type", "application/zip")
+		if _, err := w.Write(zipped); err != nil {
+			logging.Error().Err(err).Msg("failed to respond to registration request")
+			return
+		}
+	}
+}