func main() {
	flagAddr := flag.String("a", ":8888", "listening address")
	flagRootFile := flag.String("roots", "", "configuration file specifying root keys")
	flagDefaultLabel := flag.String("l", "", "specify a default label")
	flagEndpointCert := flag.String("tls-cert", "", "server certificate")
	flagEndpointKey := flag.String("tls-key", "", "server private key")
	flag.IntVar(&log.Level, "loglevel", log.LevelInfo, "log level (0 = DEBUG, 4 = ERROR)")
	flag.Parse()

	if *flagRootFile == "" {
		log.Fatal("no root file specified")
	}

	roots, err := config.Parse(*flagRootFile)
	if err != nil {
		log.Fatalf("%v", err)
	}

	for label, root := range roots {
		s, err := parseSigner(root)
		if err != nil {
			log.Criticalf("%v", err)
		}
		signers[label] = s
		if root.ACL != nil {
			whitelists[label] = root.ACL
		}
		log.Info("loaded signer ", label)
	}

	defaultLabel = *flagDefaultLabel
	initStats()

	infoHandler, err := info.NewMultiHandler(signers, defaultLabel)
	if err != nil {
		log.Criticalf("%v", err)
	}

	var localhost = whitelist.NewBasic()
	localhost.Add(net.ParseIP("127.0.0.1"))
	localhost.Add(net.ParseIP("::1"))
	metrics, err := whitelist.NewHandlerFunc(dumpMetrics, metricsDisallowed, localhost)
	if err != nil {
		log.Criticalf("failed to set up the metrics whitelist: %v", err)
	}

	http.HandleFunc("/api/v1/cfssl/authsign", dispatchRequest)
	http.Handle("/api/v1/cfssl/info", infoHandler)
	http.Handle("/api/v1/cfssl/metrics", metrics)

	if *flagEndpointCert == "" && *flagEndpointKey == "" {
		log.Info("Now listening on ", *flagAddr)
		log.Fatal(http.ListenAndServe(*flagAddr, nil))
	} else {

		log.Info("Now listening on https:// ", *flagAddr)
		log.Fatal(http.ListenAndServeTLS(*flagAddr, *flagEndpointCert, *flagEndpointKey, nil))
	}

}

// serverMain is the command line entry point to the API server. It sets up a
// new HTTP server to handle sign, bundle, and validate requests.
func serverMain(args []string, c cli.Config) error {
	conf = c
	// serve doesn't support arguments.
	if len(args) > 0 {
		return errors.New("argument is provided but not defined; please refer to the usage by flag -h")
	}

	bundler.IntermediateStash = conf.IntDir
	var err error

	if err = ubiquity.LoadPlatforms(conf.Metadata); err != nil {
		return err
	}

	log.Info("Initializing signer")
	if s, err = sign.SignerFromConfig(c); err != nil {
		log.Warningf("couldn't initialize signer: %v", err)
	}

	if ocspSigner, err = ocspsign.SignerFromConfig(c); err != nil {
		log.Warningf("couldn't initialize ocsp signer: %v", err)
	}

	registerHandlers()

	addr := net.JoinHostPort(conf.Address, strconv.Itoa(conf.Port))
	log.Info("Now listening on ", addr)
	return http.ListenAndServe(addr, nil)
}

// revCheck should check the certificate for any revocations. It
// returns a pair of booleans: the first indicates whether the certificate
// is revoked, the second indicates whether the revocations were
// successfully checked.. This leads to the following combinations:
//
//  false, false: an error was encountered while checking revocations.
//
//  false, true:  the certificate was checked successfully and
//                  it is not revoked.
//
//  true, true:   the certificate was checked successfully and
//                  it is revoked.
//
//  true, false:  failure to check revocation status causes
//                  verification to fail
func revCheck(cert *x509.Certificate) (revoked, ok bool) {
	for _, url := range cert.CRLDistributionPoints {
		if ldapURL(url) {
			log.Infof("skipping LDAP CRL: %s", url)
			continue
		}

		if revoked, ok := certIsRevokedCRL(cert, url); !ok {
			log.Warning("error checking revocation via CRL")
			if HardFail {
				return true, false
			}
			return false, false
		} else if revoked {
			log.Info("certificate is revoked via CRL")
			return true, true
		}

		if revoked, ok := certIsRevokedOCSP(cert, HardFail); !ok {
			log.Warning("error checking revocation via OCSP")
			if HardFail {
				return true, false
			}
			return false, false
		} else if revoked {
			log.Info("certificate is revoked via OCSP")
			return true, true
		}
	}

	return false, true
}

func (tr *Transport) getConfig() (*tls.Config, error) {
	if tr.ClientTrustStore != nil {
		log.Info("using client auth")
		return tr.TLSClientAuthServerConfig()
	}
	log.Info("not using client auth")
	return tr.TLSServerConfig()
}

// Handle responds to requests for the CA to sign the certificate request
// present in the "certificate_request" parameter for the host named
// in the "hostname" parameter. The certificate should be PEM-encoded. If
// provided, subject information from the "subject" parameter will be used
// in place of the subject information from the CSR.
func (h *SignHandler) Handle(w http.ResponseWriter, r *http.Request) error {
	log.Info("signature request received")

	body, err := ioutil.ReadAll(r.Body)
	if err != nil {
		return err
	}
	r.Body.Close()

	var req signer.SignRequest
	err = json.Unmarshal(body, &req)
	if err != nil {
		return err
	}

	if len(req.Hosts) == 0 {
		return errors.NewBadRequestString("missing paratmeter 'hosts'")
	}

	if req.Request == "" {
		return errors.NewBadRequestString("missing parameter 'certificate_request'")
	}

	var cert []byte
	var profile *config.SigningProfile

	policy := h.signer.Policy()
	if policy != nil && policy.Profiles != nil && req.Profile != "" {
		profile = policy.Profiles[req.Profile]
	}

	if profile == nil && policy != nil {
		profile = policy.Default
	}

	if profile.Provider != nil {
		log.Error("profile requires authentication")
		return errors.NewBadRequestString("authentication required")
	}

	cert, err = h.signer.Sign(req)
	if err != nil {
		log.Warningf("failed to sign request: %v", err)
		return err
	}

	result := map[string]string{"certificate": string(cert)}
	log.Info("wrote response")
	return api.SendResponse(w, result)
}

// worker does all the parsing and validation of the certificate(s)
// contained in a single file. It first reads all the data in the
// file, then begins parsing certificates in the file. Those
// certificates are then checked for revocation.
func worker(paths chan string, bundler chan *x509.Certificate, pool *sync.WaitGroup) {
	defer (*pool).Done()
	for {
		path, ok := <-paths
		if !ok {
			return
		}

		log.Infof("Loading %s", path)

		fileData, err := ioutil.ReadFile(path)
		if err != nil {
			log.Warningf("%v", err)
			continue
		}

		for {
			var block *pem.Block
			if len(fileData) == 0 {
				break
			}
			block, fileData = pem.Decode(fileData)
			if block == nil {
				log.Warningf("%s: no PEM data found", path)
				break
			} else if block.Type != "CERTIFICATE" {
				log.Info("Skipping non-certificate")
				continue
			}

			cert, err := x509.ParseCertificate(block.Bytes)
			if err != nil {
				log.Warningf("Invalid certificate: %v", err)
				continue
			}

			log.Infof("Validating %+v", cert.Subject)
			revoked, ok := revoke.VerifyCertificate(cert)
			if !ok {
				log.Warning("Failed to verify certificate.")
			} else if !revoked {
				bundler <- cert
			} else {
				log.Info("Skipping revoked certificate")
			}
		}
	}
}

// Handle responds to requests for the CA to generate a new private
// key and certificate on behalf of the client. The format for these
// requests is documented in the API documentation.
func (cg *CertGeneratorHandler) Handle(w http.ResponseWriter, r *http.Request) error {
	log.Info("request for CSR")

	req := new(genSignRequest)
	body, err := ioutil.ReadAll(r.Body)
	if err != nil {
		log.Warningf("failed to read request body: %v", err)
		return errors.NewBadRequest(err)
	}

	err = json.Unmarshal(body, req)
	if err != nil {
		log.Warningf("failed to unmarshal request: %v", err)
		return errors.NewBadRequest(err)
	}

	key, csr, err := cg.generator.ProcessRequest(req.Request)
	if err != nil {
		log.Warningf("failed to process CSR: %v", err)
		// The validator returns a *cfssl/errors.HttpError
		return err
	}

	certPEM, err := cg.signer.Sign(req.Hostname, csr, req.Profile)
	if err != nil {
		log.Warningf("failed to sign certificate: %v", err)
		return errors.NewBadRequest(err)
	}

	result := map[string]string{
		"private_key": string(key),
		"certificate": string(certPEM),
	}
	return sendResponse(w, result)
}

// initialCAHandler is an HTTP handler that accepts a JSON blob in the
// same format as the CSR endpoint; this blob should contain the
// identity information for the CA's root key. This endpoint is not
// suitable for creating intermediate certificates.
func initialCAHandler(w http.ResponseWriter, r *http.Request) error {
	log.Info("setting up initial CA handler")
	body, err := ioutil.ReadAll(r.Body)
	if err != nil {
		log.Warningf("failed to read request body: %v", err)
		return errors.NewBadRequest(err)
	}
	r.Body.Close()

	req := new(csr.CertificateRequest)
	req.KeyRequest = csr.NewBasicKeyRequest()
	err = json.Unmarshal(body, req)
	if err != nil {
		log.Warningf("failed to unmarshal request: %v", err)
		return errors.NewBadRequest(err)
	}

	cert, _, key, err := initca.New(req)
	if err != nil {
		log.Warningf("failed to initialise new CA: %v", err)
		return err
	}

	response := api.NewSuccessResponse(&NewCA{string(key), string(cert)})

	enc := json.NewEncoder(w)
	err = enc.Encode(response)
	return err
}

// NewCertGeneratorHandler builds a new handler for generating
// certificates directly from certificate requests; the validator covers
// the certificate request and the CA's key and certificate are used to
// sign the generated request. If remote is not an empty string, the
// handler will send signature requests to the CFSSL instance contained
// in remote.
func NewCertGeneratorHandler(validator Validator, caFile, caKeyFile string, policy *config.Signing) (http.Handler, error) {
	var err error
	log.Info("setting up new generator / signer")
	cg := new(CertGeneratorHandler)

	if policy == nil {
		policy = &config.Signing{
			Default:  config.DefaultConfig(),
			Profiles: nil,
		}
	}

	root := universal.Root{
		Config: map[string]string{
			"ca-file":     caFile,
			"ca-key-file": caKeyFile,
		},
	}
	if cg.signer, err = universal.NewSigner(root, policy); err != nil {
		log.Errorf("setting up signer failed: %v", err)
		return nil, err
	}

	cg.generator = &csr.Generator{Validator: validator}

	return api.HTTPHandler{Handler: cg, Methods: []string{"POST"}}, nil
}

// scanInfoHandler is an HTTP handler that returns a JSON blob result describing
// the possible families and scans to be run.
func scanInfoHandler(w http.ResponseWriter, r *http.Request) error {
	log.Info("setting up scaninfo handler")
	response := api.NewSuccessResponse(scan.Default)
	enc := json.NewEncoder(w)
	err := enc.Encode(response)
	return err
}

// Generate creates a new CSR from a CertificateRequest structure and
// an existing key. The KeyRequest field is ignored.
func Generate(priv crypto.Signer, req *CertificateRequest) (csr []byte, err error) {
	sigAlgo := helpers.SignerAlgo(priv, crypto.SHA256)
	if sigAlgo == x509.UnknownSignatureAlgorithm {
		return nil, cferr.New(cferr.PrivateKeyError, cferr.Unavailable)
	}

	var tpl = x509.CertificateRequest{
		Subject:            req.Name(),
		SignatureAlgorithm: sigAlgo,
	}

	for i := range req.Hosts {
		if ip := net.ParseIP(req.Hosts[i]); ip != nil {
			tpl.IPAddresses = append(tpl.IPAddresses, ip)
		} else {
			tpl.DNSNames = append(tpl.DNSNames, req.Hosts[i])
		}
	}

	csr, err = x509.CreateCertificateRequest(rand.Reader, &tpl, priv)
	if err != nil {
		log.Errorf("failed to generate a CSR: %v", err)
		err = cferr.Wrap(cferr.CSRError, cferr.BadRequest, err)
		return
	}
	block := pem.Block{
		Type:  "CERTIFICATE REQUEST",
		Bytes: csr,
	}

	log.Info("encoded CSR")
	csr = pem.EncodeToMemory(&block)
	return
}

// check a cert against a specific CRL. Returns the same bool pair
// as revCheck.
func certIsRevokedCRL(cert *x509.Certificate, url string) (revoked, ok bool) {
	crl, ok := CRLSet[url]
	if ok && crl == nil {
		ok = false
		delete(CRLSet, url)
	}

	var shouldFetchCRL = true
	if ok {
		if !crl.HasExpired(time.Now()) {
			shouldFetchCRL = false
		}
	}

	if shouldFetchCRL {
		var err error
		crl, err = fetchCRL(url)
		if err != nil {
			log.Warningf("failed to fetch CRL: %v", err)
			return false, false
		}
		CRLSet[url] = crl
	}

	for _, revoked := range crl.TBSCertList.RevokedCertificates {
		if cert.SerialNumber.Cmp(revoked.SerialNumber) == 0 {
			log.Info("Serial number match: intermediate is revoked.")
			return true, true
		}
	}

	return false, true
}

func TestOverrideSubject(t *testing.T) {
	csrPEM, err := ioutil.ReadFile(fullSubjectCSR)
	if err != nil {
		t.Fatalf("%v", err)
	}

	req := &signer.Subject{
		Names: []csr.Name{
			{O: "example.net"},
		},
	}

	s := newCustomSigner(t, testECDSACaFile, testECDSACaKeyFile)

	request := signer.SignRequest{
		Hosts:   []string{"127.0.0.1", "localhost", "[email protected]"},
		Request: string(csrPEM),
		Subject: req,
	}

	certPEM, err := s.Sign(request)

	if err != nil {
		t.Fatalf("%v", err)
	}

	cert, err := helpers.ParseCertificatePEM(certPEM)
	if err != nil {
		t.Fatalf("%v", err)
	}

	block, _ := pem.Decode(csrPEM)
	template, err := x509.ParseCertificateRequest(block.Bytes)
	if err != nil {
		t.Fatal(err.Error())
	}
	if cert.Subject.Organization[0] != "example.net" {
		t.Fatalf("Failed to override subject: want example.net but have %s", cert.Subject.Organization[0])
	}

	if cert.Subject.Country[0] != template.Subject.Country[0] {
		t.Fatal("Failed to override Country")
	}

	if cert.Subject.Locality[0] != template.Subject.Locality[0] {
		t.Fatal("Failed to override Locality")
	}

	if cert.Subject.Organization[0] == template.Subject.Organization[0] {
		t.Fatal("Shouldn't have overrode Organization")
	}

	if cert.Subject.OrganizationalUnit[0] != template.Subject.OrganizationalUnit[0] {
		t.Fatal("Failed to override OrganizationalUnit")
	}

	log.Info("Overrode subject info")
}

func main() {
	var addr, conf string
	flag.StringVar(&addr, "a", "127.0.0.1:9876", "`address` of server")
	flag.StringVar(&conf, "f", "server.json", "config `file` to use")
	flag.Parse()

	var id = new(core.Identity)
	data, err := ioutil.ReadFile(conf)
	if err != nil {
		exlib.Err(1, err, "reading config file")
	}

	err = json.Unmarshal(data, id)
	if err != nil {
		exlib.Err(1, err, "parsing config file")
	}

	tr, err := transport.New(exlib.Before, id)
	if err != nil {
		exlib.Err(1, err, "creating transport")
	}

	l, err := transport.Listen(addr, tr)
	if err != nil {
		exlib.Err(1, err, "setting up listener")
	}

	var errChan = make(chan error, 0)
	go func(ec <-chan error) {
		for {
			err, ok := <-ec
			if !ok {
				log.Warning("error channel closed, future errors will not be reported")
				break
			}
			log.Errorf("auto update error: %v", err)
		}
	}(errChan)

	log.Info("setting up auto-update")
	go l.AutoUpdate(nil, errChan)

	log.Info("listening on ", addr)
	exlib.Warn(serve(l), "serving listener")
}

// Handle implements an http.Handler interface for the bundle handler.
func (h *Handler) Handle(w http.ResponseWriter, r *http.Request) error {
	blob, matched, err := api.ProcessRequestFirstMatchOf(r,
		[][]string{
			{"certificate"},
			{"domain"},
		})
	if err != nil {
		log.Warningf("invalid request: %v", err)
		return err
	}

	flavor := blob["flavor"]
	bf := bundler.Ubiquitous
	if flavor != "" {
		bf = bundler.BundleFlavor(flavor)
	}
	log.Infof("request for flavor %v", bf)

	var result *bundler.Bundle
	switch matched[0] {
	case "domain":
		bundle, err := h.bundler.BundleFromRemote(blob["domain"], blob["ip"], bf)
		if err != nil {
			log.Warningf("couldn't bundle from remote: %v", err)
			return err
		}
		result = bundle
	case "certificate":
		bundle, err := h.bundler.BundleFromPEMorDER([]byte(blob["certificate"]), []byte(blob["private_key"]), bf, "")
		if err != nil {
			log.Warning("bad PEM certifcate or private key")
			return err
		}

		serverName := blob["domain"]
		ip := blob["ip"]

		if serverName != "" {
			err := bundle.Cert.VerifyHostname(serverName)
			if err != nil {
				return errors.Wrap(errors.CertificateError, errors.VerifyFailed, err)
			}

		}

		if ip != "" {
			err := bundle.Cert.VerifyHostname(ip)
			if err != nil {
				return errors.Wrap(errors.CertificateError, errors.VerifyFailed, err)
			}
		}

		result = bundle
	}
	log.Info("wrote response")
	return api.SendResponse(w, result)
}

// NewHandler builds a new Handler from the
// validation function provided.
func NewHandler(validator Validator) (http.Handler, error) {
	log.Info("setting up key / CSR generator")
	return &api.HTTPHandler{
		Handler: &Handler{
			generator: &csr.Generator{Validator: validator},
		},
		Methods: []string{"POST"},
	}, nil
}

// Handle responds to requests for the CA to sign the certificate
// present in the "cert" parameter for the host named in the "hostname"
// parameter. The certificate should be PEM-encoded.
func (h *SignHandler) Handle(w http.ResponseWriter, r *http.Request) error {
	log.Info("signature request received")
	blob, err := processRequestRequired(r, []string{"hostname", "certificate_request"})
	if err != nil {
		return err
	}

	certificate := []byte(blob["certificate_request"])
	cert, err := h.signer.Sign(blob["hostname"], certificate, blob["profile"])
	if err != nil {
		log.Warningf("failed to sign request: %v", err)
		return errors.NewBadRequest(err)
	}

	result := map[string]string{"certificate": string(cert)}
	log.Info("wrote response")
	return sendResponse(w, result)
}

// Handle responds to requests for the CA to sign the certificate request
// present in the "certificate_request" parameter for the host named
// in the "hostname" parameter. The certificate should be PEM-encoded. If
// provided, subject information from the "subject" parameter will be used
// in place of the subject information from the CSR.
func (h *Handler) Handle(w http.ResponseWriter, r *http.Request) error {
	log.Info("signature request received")

	body, err := ioutil.ReadAll(r.Body)
	if err != nil {
		return err
	}
	r.Body.Close()

	var req jsonSignRequest

	err = json.Unmarshal(body, &req)
	if err != nil {
		return errors.NewBadRequestString("Unable to parse sign request")
	}

	signReq := jsonReqToTrue(req)

	if req.Request == "" {
		return errors.NewBadRequestString("missing parameter 'certificate_request'")
	}

	var cert []byte
	profile, err := signer.Profile(h.signer, req.Profile)
	if err != nil {
		return err
	}

	if profile.Provider != nil {
		log.Error("profile requires authentication")
		return errors.NewBadRequestString("authentication required")
	}

	cert, err = h.signer.Sign(signReq)
	if err != nil {
		log.Warningf("failed to sign request: %v", err)
		return err
	}

	result := map[string]string{"certificate": string(cert)}
	log.Info("wrote response")
	return api.SendResponse(w, result)
}

func NewBundleHandler(caBundleFile, intBundleFile string) (http.Handler, error) {
	var err error

	b := new(BundlerHandler)
	if b.bundler, err = bundler.NewBundler(caBundleFile, intBundleFile); err != nil {
		return nil, err
	}

	log.Info("bundler API ready")
	return HttpHandler{b, "POST"}, nil
}

// NewGeneratorHandler builds a new GeneratorHandler from the
// validation function provided.
func NewCertGeneratorHandler(validator Validator, caFile, caKeyFile string) (http.Handler, error) {
	var err error
	log.Info("setting up new generator / signer")
	cg := new(CertGeneratorHandler)
	if cg.signer, err = signer.NewSigner(caFile, caKeyFile, nil); err != nil {
		return nil, err
	}
	cg.generator = &csr.Generator{validator}

	return HttpHandler{cg, "POST"}, nil
}