From 38004167cb41e59f1cd854906e56056a4e53156b Mon Sep 17 00:00:00 2001
From: Andy Doan <andy@foundries.io>
Date: Mon, 10 Oct 2022 15:45:21 -0500
Subject: [PATCH] Create a main method for standalone server

Signed-off-by: Andy Doan <andy@foundries.io>
---
 cmd/main.go | 128 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 128 insertions(+)
 create mode 100644 cmd/main.go

diff --git a/cmd/main.go b/cmd/main.go
new file mode 100644
index 0000000..97379f1
--- /dev/null
+++ b/cmd/main.go
@@ -0,0 +1,128 @@
+package main
+
+import (
+	"context"
+	"crypto/ecdsa"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
+	"flag"
+	"fmt"
+	"net"
+	"net/http"
+	"os"
+
+	est "github.com/foundriesio/estserver"
+	"github.com/labstack/echo/v4"
+	"github.com/rs/zerolog"
+)
+
+type requiredStr struct {
+	name  string
+	value string
+	help  string
+}
+
+func main() {
+	required := []*requiredStr{
+		{name: "tls-key", help: "Private key file of tls-cert"},
+		{name: "tls-cert", help: "TLS PEM encoded certificate"},
+		{name: "ca-key", help: "Private key file of EST CA"},
+		{name: "ca-cert", help: "EST CA for handling enrollments"},
+		{name: "root-cert", help: "EST CA PEM encoded root certificate"},
+	}
+	port := flag.Int("port", 8443, "Port to listen on")
+
+	for _, opt := range required {
+		flag.StringVar(&opt.value, opt.name, "", opt.help)
+	}
+
+	flag.Parse()
+
+	log := est.InitLogger("")
+	ctx := est.CtxWithLog(context.Background(), log)
+
+	evt := log.Info().Int("port", *port)
+	for _, opt := range required {
+		if len(opt.value) == 0 {
+			log.Fatal().Msgf("Missing required option: %s", opt.name)
+		}
+		evt = evt.Str(opt.name, opt.value)
+	}
+	evt.Msg("Starting")
+
+	kp, err := tls.LoadX509KeyPair(required[1].value, required[0].value)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Unable to loads TLS keypair")
+	}
+
+	rootCert := loadCert(log, required[4].value)
+	caCert := loadCert(log, required[3].value)
+	caKey := loadKey(log, required[2].value)
+
+	caPool := x509.NewCertPool()
+	caPool.AddCert(rootCert)
+	caPool.AddCert(caCert)
+
+	tlsCerts := est.TlsCerts{
+		Server: &kp,
+		Roots:  caPool,
+	}
+	tlsHandler, err := est.NewStaticTlsCertHandler(&tlsCerts)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Unable to create tls cert handler")
+	}
+
+	svc := est.NewService(rootCert, caCert, caKey)
+
+	e := echo.New()
+	s := http.Server{
+		Addr:        fmt.Sprintf(":%d", *port),
+		BaseContext: func(net.Listener) context.Context { return ctx },
+		Handler:     e,
+		TLSConfig: &tls.Config{
+			MinVersion: tls.VersionTLS12,
+			ClientAuth: tls.VerifyClientCertIfGiven,
+		},
+	}
+	if err = est.ApplyTlsCertHandler(s.TLSConfig, tlsHandler); err != nil {
+		log.Fatal().Err(err).Msg("Unable to configure TLS handler")
+	}
+	est.RegisterEchoHandlers(svc, e)
+
+	if err := e.StartServer(&s); err != http.ErrServerClosed {
+		log.Fatal().Err(err).Msg("Unable to run server")
+	}
+}
+
+func loadCert(log zerolog.Logger, fileName string) *x509.Certificate {
+	bytes, err := os.ReadFile(fileName)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Can't read certificate")
+	}
+	block, extra := pem.Decode(bytes)
+	if extra != nil && len(extra) > 0 {
+		log.Fatal().Msgf("Can't parse CA key file. Extra bytes: %s", string(extra))
+	}
+	cert, err := x509.ParseCertificate(block.Bytes)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Can't parse certificate")
+	}
+	return cert
+}
+
+func loadKey(log zerolog.Logger, keyFile string) *ecdsa.PrivateKey {
+	bytes, err := os.ReadFile(keyFile)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Can't read CA key file")
+	}
+	block, extra := pem.Decode(bytes)
+	if extra != nil && len(extra) > 0 {
+		log.Fatal().Msgf("Can't parse CA key file. Extra bytes: %s", string(extra))
+	}
+	key, err := x509.ParseECPrivateKey(block.Bytes)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Can't parse CA key file")
+	}
+	return key
+}