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4 files changed, 0 insertions, 1567 deletions

diff --git a/vendor/golang.org/x/crypto/acme/autocert/autocert.go b/vendor/golang.org/x/crypto/acme/autocert/autocert.go
deleted file mode 100644
index 4c2fc07..0000000
--- a/vendor/golang.org/x/crypto/acme/autocert/autocert.go
+++ /dev/null
@@ -1,1139 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package autocert provides automatic access to certificates from Let's Encrypt
-// and any other ACME-based CA.
-//
-// This package is a work in progress and makes no API stability promises.
-package autocert
-
-import (
-	"bytes"
-	"context"
-	"crypto"
-	"crypto/ecdsa"
-	"crypto/elliptic"
-	"crypto/rand"
-	"crypto/rsa"
-	"crypto/tls"
-	"crypto/x509"
-	"crypto/x509/pkix"
-	"encoding/pem"
-	"errors"
-	"fmt"
-	"io"
-	mathrand "math/rand"
-	"net"
-	"net/http"
-	"path"
-	"strings"
-	"sync"
-	"time"
-
-	"golang.org/x/crypto/acme"
-)
-
-// createCertRetryAfter is how much time to wait before removing a failed state
-// entry due to an unsuccessful createCert call.
-// This is a variable instead of a const for testing.
-// TODO: Consider making it configurable or an exp backoff?
-var createCertRetryAfter = time.Minute
-
-// pseudoRand is safe for concurrent use.
-var pseudoRand *lockedMathRand
-
-func init() {
-	src := mathrand.NewSource(time.Now().UnixNano())
-	pseudoRand = &lockedMathRand{rnd: mathrand.New(src)}
-}
-
-// AcceptTOS is a Manager.Prompt function that always returns true to
-// indicate acceptance of the CA's Terms of Service during account
-// registration.
-func AcceptTOS(tosURL string) bool { return true }
-
-// HostPolicy specifies which host names the Manager is allowed to respond to.
-// It returns a non-nil error if the host should be rejected.
-// The returned error is accessible via tls.Conn.Handshake and its callers.
-// See Manager's HostPolicy field and GetCertificate method docs for more details.
-type HostPolicy func(ctx context.Context, host string) error
-
-// HostWhitelist returns a policy where only the specified host names are allowed.
-// Only exact matches are currently supported. Subdomains, regexp or wildcard
-// will not match.
-func HostWhitelist(hosts ...string) HostPolicy {
-	whitelist := make(map[string]bool, len(hosts))
-	for _, h := range hosts {
-		whitelist[h] = true
-	}
-	return func(_ context.Context, host string) error {
-		if !whitelist[host] {
-			return errors.New("acme/autocert: host not configured")
-		}
-		return nil
-	}
-}
-
-// defaultHostPolicy is used when Manager.HostPolicy is not set.
-func defaultHostPolicy(context.Context, string) error {
-	return nil
-}
-
-// Manager is a stateful certificate manager built on top of acme.Client.
-// It obtains and refreshes certificates automatically using "tls-alpn-01",
-// "tls-sni-01", "tls-sni-02" and "http-01" challenge types,
-// as well as providing them to a TLS server via tls.Config.
-//
-// You must specify a cache implementation, such as DirCache,
-// to reuse obtained certificates across program restarts.
-// Otherwise your server is very likely to exceed the certificate
-// issuer's request rate limits.
-type Manager struct {
-	// Prompt specifies a callback function to conditionally accept a CA's Terms of Service (TOS).
-	// The registration may require the caller to agree to the CA's TOS.
-	// If so, Manager calls Prompt with a TOS URL provided by the CA. Prompt should report
-	// whether the caller agrees to the terms.
-	//
-	// To always accept the terms, the callers can use AcceptTOS.
-	Prompt func(tosURL string) bool
-
-	// Cache optionally stores and retrieves previously-obtained certificates
-	// and other state. If nil, certs will only be cached for the lifetime of
-	// the Manager. Multiple Managers can share the same Cache.
-	//
-	// Using a persistent Cache, such as DirCache, is strongly recommended.
-	Cache Cache
-
-	// HostPolicy controls which domains the Manager will attempt
-	// to retrieve new certificates for. It does not affect cached certs.
-	//
-	// If non-nil, HostPolicy is called before requesting a new cert.
-	// If nil, all hosts are currently allowed. This is not recommended,
-	// as it opens a potential attack where clients connect to a server
-	// by IP address and pretend to be asking for an incorrect host name.
-	// Manager will attempt to obtain a certificate for that host, incorrectly,
-	// eventually reaching the CA's rate limit for certificate requests
-	// and making it impossible to obtain actual certificates.
-	//
-	// See GetCertificate for more details.
-	HostPolicy HostPolicy
-
-	// RenewBefore optionally specifies how early certificates should
-	// be renewed before they expire.
-	//
-	// If zero, they're renewed 30 days before expiration.
-	RenewBefore time.Duration
-
-	// Client is used to perform low-level operations, such as account registration
-	// and requesting new certificates.
-	//
-	// If Client is nil, a zero-value acme.Client is used with acme.LetsEncryptURL
-	// as directory endpoint. If the Client.Key is nil, a new ECDSA P-256 key is
-	// generated and, if Cache is not nil, stored in cache.
-	//
-	// Mutating the field after the first call of GetCertificate method will have no effect.
-	Client *acme.Client
-
-	// Email optionally specifies a contact email address.
-	// This is used by CAs, such as Let's Encrypt, to notify about problems
-	// with issued certificates.
-	//
-	// If the Client's account key is already registered, Email is not used.
-	Email string
-
-	// ForceRSA used to make the Manager generate RSA certificates. It is now ignored.
-	//
-	// Deprecated: the Manager will request the correct type of certificate based
-	// on what each client supports.
-	ForceRSA bool
-
-	// ExtraExtensions are used when generating a new CSR (Certificate Request),
-	// thus allowing customization of the resulting certificate.
-	// For instance, TLS Feature Extension (RFC 7633) can be used
-	// to prevent an OCSP downgrade attack.
-	//
-	// The field value is passed to crypto/x509.CreateCertificateRequest
-	// in the template's ExtraExtensions field as is.
-	ExtraExtensions []pkix.Extension
-
-	clientMu sync.Mutex
-	client   *acme.Client // initialized by acmeClient method
-
-	stateMu sync.Mutex
-	state   map[certKey]*certState
-
-	// renewal tracks the set of domains currently running renewal timers.
-	renewalMu sync.Mutex
-	renewal   map[certKey]*domainRenewal
-
-	// tokensMu guards the rest of the fields: tryHTTP01, certTokens and httpTokens.
-	tokensMu sync.RWMutex
-	// tryHTTP01 indicates whether the Manager should try "http-01" challenge type
-	// during the authorization flow.
-	tryHTTP01 bool
-	// httpTokens contains response body values for http-01 challenges
-	// and is keyed by the URL path at which a challenge response is expected
-	// to be provisioned.
-	// The entries are stored for the duration of the authorization flow.
-	httpTokens map[string][]byte
-	// certTokens contains temporary certificates for tls-sni and tls-alpn challenges
-	// and is keyed by token domain name, which matches server name of ClientHello.
-	// Keys always have ".acme.invalid" suffix for tls-sni. Otherwise, they are domain names
-	// for tls-alpn.
-	// The entries are stored for the duration of the authorization flow.
-	certTokens map[string]*tls.Certificate
-	// nowFunc, if not nil, returns the current time. This may be set for
-	// testing purposes.
-	nowFunc func() time.Time
-}
-
-// certKey is the key by which certificates are tracked in state, renewal and cache.
-type certKey struct {
-	domain  string // without trailing dot
-	isRSA   bool   // RSA cert for legacy clients (as opposed to default ECDSA)
-	isToken bool   // tls-based challenge token cert; key type is undefined regardless of isRSA
-}
-
-func (c certKey) String() string {
-	if c.isToken {
-		return c.domain + "+token"
-	}
-	if c.isRSA {
-		return c.domain + "+rsa"
-	}
-	return c.domain
-}
-
-// TLSConfig creates a new TLS config suitable for net/http.Server servers,
-// supporting HTTP/2 and the tls-alpn-01 ACME challenge type.
-func (m *Manager) TLSConfig() *tls.Config {
-	return &tls.Config{
-		GetCertificate: m.GetCertificate,
-		NextProtos: []string{
-			"h2", "http/1.1", // enable HTTP/2
-			acme.ALPNProto, // enable tls-alpn ACME challenges
-		},
-	}
-}
-
-// GetCertificate implements the tls.Config.GetCertificate hook.
-// It provides a TLS certificate for hello.ServerName host, including answering
-// tls-alpn-01 and *.acme.invalid (tls-sni-01 and tls-sni-02) challenges.
-// All other fields of hello are ignored.
-//
-// If m.HostPolicy is non-nil, GetCertificate calls the policy before requesting
-// a new cert. A non-nil error returned from m.HostPolicy halts TLS negotiation.
-// The error is propagated back to the caller of GetCertificate and is user-visible.
-// This does not affect cached certs. See HostPolicy field description for more details.
-//
-// If GetCertificate is used directly, instead of via Manager.TLSConfig, package users will
-// also have to add acme.ALPNProto to NextProtos for tls-alpn-01, or use HTTPHandler
-// for http-01. (The tls-sni-* challenges have been deprecated by popular ACME providers
-// due to security issues in the ecosystem.)
-func (m *Manager) GetCertificate(hello *tls.ClientHelloInfo) (*tls.Certificate, error) {
-	if m.Prompt == nil {
-		return nil, errors.New("acme/autocert: Manager.Prompt not set")
-	}
-
-	name := hello.ServerName
-	if name == "" {
-		return nil, errors.New("acme/autocert: missing server name")
-	}
-	if !strings.Contains(strings.Trim(name, "."), ".") {
-		return nil, errors.New("acme/autocert: server name component count invalid")
-	}
-	if strings.ContainsAny(name, `+/\`) {
-		return nil, errors.New("acme/autocert: server name contains invalid character")
-	}
-
-	// In the worst-case scenario, the timeout needs to account for caching, host policy,
-	// domain ownership verification and certificate issuance.
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
-	defer cancel()
-
-	// Check whether this is a token cert requested for TLS-SNI or TLS-ALPN challenge.
-	if wantsTokenCert(hello) {
-		m.tokensMu.RLock()
-		defer m.tokensMu.RUnlock()
-		// It's ok to use the same token cert key for both tls-sni and tls-alpn
-		// because there's always at most 1 token cert per on-going domain authorization.
-		// See m.verify for details.
-		if cert := m.certTokens[name]; cert != nil {
-			return cert, nil
-		}
-		if cert, err := m.cacheGet(ctx, certKey{domain: name, isToken: true}); err == nil {
-			return cert, nil
-		}
-		// TODO: cache error results?
-		return nil, fmt.Errorf("acme/autocert: no token cert for %q", name)
-	}
-
-	// regular domain
-	ck := certKey{
-		domain: strings.TrimSuffix(name, "."), // golang.org/issue/18114
-		isRSA:  !supportsECDSA(hello),
-	}
-	cert, err := m.cert(ctx, ck)
-	if err == nil {
-		return cert, nil
-	}
-	if err != ErrCacheMiss {
-		return nil, err
-	}
-
-	// first-time
-	if err := m.hostPolicy()(ctx, name); err != nil {
-		return nil, err
-	}
-	cert, err = m.createCert(ctx, ck)
-	if err != nil {
-		return nil, err
-	}
-	m.cachePut(ctx, ck, cert)
-	return cert, nil
-}
-
-// wantsTokenCert reports whether a TLS request with SNI is made by a CA server
-// for a challenge verification.
-func wantsTokenCert(hello *tls.ClientHelloInfo) bool {
-	// tls-alpn-01
-	if len(hello.SupportedProtos) == 1 && hello.SupportedProtos[0] == acme.ALPNProto {
-		return true
-	}
-	// tls-sni-xx
-	return strings.HasSuffix(hello.ServerName, ".acme.invalid")
-}
-
-func supportsECDSA(hello *tls.ClientHelloInfo) bool {
-	// The "signature_algorithms" extension, if present, limits the key exchange
-	// algorithms allowed by the cipher suites. See RFC 5246, section 7.4.1.4.1.
-	if hello.SignatureSchemes != nil {
-		ecdsaOK := false
-	schemeLoop:
-		for _, scheme := range hello.SignatureSchemes {
-			const tlsECDSAWithSHA1 tls.SignatureScheme = 0x0203 // constant added in Go 1.10
-			switch scheme {
-			case tlsECDSAWithSHA1, tls.ECDSAWithP256AndSHA256,
-				tls.ECDSAWithP384AndSHA384, tls.ECDSAWithP521AndSHA512:
-				ecdsaOK = true
-				break schemeLoop
-			}
-		}
-		if !ecdsaOK {
-			return false
-		}
-	}
-	if hello.SupportedCurves != nil {
-		ecdsaOK := false
-		for _, curve := range hello.SupportedCurves {
-			if curve == tls.CurveP256 {
-				ecdsaOK = true
-				break
-			}
-		}
-		if !ecdsaOK {
-			return false
-		}
-	}
-	for _, suite := range hello.CipherSuites {
-		switch suite {
-		case tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
-			tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
-			tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
-			tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
-			tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
-			tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
-			tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305:
-			return true
-		}
-	}
-	return false
-}
-
-// HTTPHandler configures the Manager to provision ACME "http-01" challenge responses.
-// It returns an http.Handler that responds to the challenges and must be
-// running on port 80. If it receives a request that is not an ACME challenge,
-// it delegates the request to the optional fallback handler.
-//
-// If fallback is nil, the returned handler redirects all GET and HEAD requests
-// to the default TLS port 443 with 302 Found status code, preserving the original
-// request path and query. It responds with 400 Bad Request to all other HTTP methods.
-// The fallback is not protected by the optional HostPolicy.
-//
-// Because the fallback handler is run with unencrypted port 80 requests,
-// the fallback should not serve TLS-only requests.
-//
-// If HTTPHandler is never called, the Manager will only use the "tls-alpn-01"
-// challenge for domain verification.
-func (m *Manager) HTTPHandler(fallback http.Handler) http.Handler {
-	m.tokensMu.Lock()
-	defer m.tokensMu.Unlock()
-	m.tryHTTP01 = true
-
-	if fallback == nil {
-		fallback = http.HandlerFunc(handleHTTPRedirect)
-	}
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if !strings.HasPrefix(r.URL.Path, "/.well-known/acme-challenge/") {
-			fallback.ServeHTTP(w, r)
-			return
-		}
-		// A reasonable context timeout for cache and host policy only,
-		// because we don't wait for a new certificate issuance here.
-		ctx, cancel := context.WithTimeout(r.Context(), time.Minute)
-		defer cancel()
-		if err := m.hostPolicy()(ctx, r.Host); err != nil {
-			http.Error(w, err.Error(), http.StatusForbidden)
-			return
-		}
-		data, err := m.httpToken(ctx, r.URL.Path)
-		if err != nil {
-			http.Error(w, err.Error(), http.StatusNotFound)
-			return
-		}
-		w.Write(data)
-	})
-}
-
-func handleHTTPRedirect(w http.ResponseWriter, r *http.Request) {
-	if r.Method != "GET" && r.Method != "HEAD" {
-		http.Error(w, "Use HTTPS", http.StatusBadRequest)
-		return
-	}
-	target := "https://" + stripPort(r.Host) + r.URL.RequestURI()
-	http.Redirect(w, r, target, http.StatusFound)
-}
-
-func stripPort(hostport string) string {
-	host, _, err := net.SplitHostPort(hostport)
-	if err != nil {
-		return hostport
-	}
-	return net.JoinHostPort(host, "443")
-}
-
-// cert returns an existing certificate either from m.state or cache.
-// If a certificate is found in cache but not in m.state, the latter will be filled
-// with the cached value.
-func (m *Manager) cert(ctx context.Context, ck certKey) (*tls.Certificate, error) {
-	m.stateMu.Lock()
-	if s, ok := m.state[ck]; ok {
-		m.stateMu.Unlock()
-		s.RLock()
-		defer s.RUnlock()
-		return s.tlscert()
-	}
-	defer m.stateMu.Unlock()
-	cert, err := m.cacheGet(ctx, ck)
-	if err != nil {
-		return nil, err
-	}
-	signer, ok := cert.PrivateKey.(crypto.Signer)
-	if !ok {
-		return nil, errors.New("acme/autocert: private key cannot sign")
-	}
-	if m.state == nil {
-		m.state = make(map[certKey]*certState)
-	}
-	s := &certState{
-		key:  signer,
-		cert: cert.Certificate,
-		leaf: cert.Leaf,
-	}
-	m.state[ck] = s
-	go m.renew(ck, s.key, s.leaf.NotAfter)
-	return cert, nil
-}
-
-// cacheGet always returns a valid certificate, or an error otherwise.
-// If a cached certificate exists but is not valid, ErrCacheMiss is returned.
-func (m *Manager) cacheGet(ctx context.Context, ck certKey) (*tls.Certificate, error) {
-	if m.Cache == nil {
-		return nil, ErrCacheMiss
-	}
-	data, err := m.Cache.Get(ctx, ck.String())
-	if err != nil {
-		return nil, err
-	}
-
-	// private
-	priv, pub := pem.Decode(data)
-	if priv == nil || !strings.Contains(priv.Type, "PRIVATE") {
-		return nil, ErrCacheMiss
-	}
-	privKey, err := parsePrivateKey(priv.Bytes)
-	if err != nil {
-		return nil, err
-	}
-
-	// public
-	var pubDER [][]byte
-	for len(pub) > 0 {
-		var b *pem.Block
-		b, pub = pem.Decode(pub)
-		if b == nil {
-			break
-		}
-		pubDER = append(pubDER, b.Bytes)
-	}
-	if len(pub) > 0 {
-		// Leftover content not consumed by pem.Decode. Corrupt. Ignore.
-		return nil, ErrCacheMiss
-	}
-
-	// verify and create TLS cert
-	leaf, err := validCert(ck, pubDER, privKey, m.now())
-	if err != nil {
-		return nil, ErrCacheMiss
-	}
-	tlscert := &tls.Certificate{
-		Certificate: pubDER,
-		PrivateKey:  privKey,
-		Leaf:        leaf,
-	}
-	return tlscert, nil
-}
-
-func (m *Manager) cachePut(ctx context.Context, ck certKey, tlscert *tls.Certificate) error {
-	if m.Cache == nil {
-		return nil
-	}
-
-	// contains PEM-encoded data
-	var buf bytes.Buffer
-
-	// private
-	switch key := tlscert.PrivateKey.(type) {
-	case *ecdsa.PrivateKey:
-		if err := encodeECDSAKey(&buf, key); err != nil {
-			return err
-		}
-	case *rsa.PrivateKey:
-		b := x509.MarshalPKCS1PrivateKey(key)
-		pb := &pem.Block{Type: "RSA PRIVATE KEY", Bytes: b}
-		if err := pem.Encode(&buf, pb); err != nil {
-			return err
-		}
-	default:
-		return errors.New("acme/autocert: unknown private key type")
-	}
-
-	// public
-	for _, b := range tlscert.Certificate {
-		pb := &pem.Block{Type: "CERTIFICATE", Bytes: b}
-		if err := pem.Encode(&buf, pb); err != nil {
-			return err
-		}
-	}
-
-	return m.Cache.Put(ctx, ck.String(), buf.Bytes())
-}
-
-func encodeECDSAKey(w io.Writer, key *ecdsa.PrivateKey) error {
-	b, err := x509.MarshalECPrivateKey(key)
-	if err != nil {
-		return err
-	}
-	pb := &pem.Block{Type: "EC PRIVATE KEY", Bytes: b}
-	return pem.Encode(w, pb)
-}
-
-// createCert starts the domain ownership verification and returns a certificate
-// for that domain upon success.
-//
-// If the domain is already being verified, it waits for the existing verification to complete.
-// Either way, createCert blocks for the duration of the whole process.
-func (m *Manager) createCert(ctx context.Context, ck certKey) (*tls.Certificate, error) {
-	// TODO: maybe rewrite this whole piece using sync.Once
-	state, err := m.certState(ck)
-	if err != nil {
-		return nil, err
-	}
-	// state may exist if another goroutine is already working on it
-	// in which case just wait for it to finish
-	if !state.locked {
-		state.RLock()
-		defer state.RUnlock()
-		return state.tlscert()
-	}
-
-	// We are the first; state is locked.
-	// Unblock the readers when domain ownership is verified
-	// and we got the cert or the process failed.
-	defer state.Unlock()
-	state.locked = false
-
-	der, leaf, err := m.authorizedCert(ctx, state.key, ck)
-	if err != nil {
-		// Remove the failed state after some time,
-		// making the manager call createCert again on the following TLS hello.
-		time.AfterFunc(createCertRetryAfter, func() {
-			defer testDidRemoveState(ck)
-			m.stateMu.Lock()
-			defer m.stateMu.Unlock()
-			// Verify the state hasn't changed and it's still invalid
-			// before deleting.
-			s, ok := m.state[ck]
-			if !ok {
-				return
-			}
-			if _, err := validCert(ck, s.cert, s.key, m.now()); err == nil {
-				return
-			}
-			delete(m.state, ck)
-		})
-		return nil, err
-	}
-	state.cert = der
-	state.leaf = leaf
-	go m.renew(ck, state.key, state.leaf.NotAfter)
-	return state.tlscert()
-}
-
-// certState returns a new or existing certState.
-// If a new certState is returned, state.exist is false and the state is locked.
-// The returned error is non-nil only in the case where a new state could not be created.
-func (m *Manager) certState(ck certKey) (*certState, error) {
-	m.stateMu.Lock()
-	defer m.stateMu.Unlock()
-	if m.state == nil {
-		m.state = make(map[certKey]*certState)
-	}
-	// existing state
-	if state, ok := m.state[ck]; ok {
-		return state, nil
-	}
-
-	// new locked state
-	var (
-		err error
-		key crypto.Signer
-	)
-	if ck.isRSA {
-		key, err = rsa.GenerateKey(rand.Reader, 2048)
-	} else {
-		key, err = ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
-	}
-	if err != nil {
-		return nil, err
-	}
-
-	state := &certState{
-		key:    key,
-		locked: true,
-	}
-	state.Lock() // will be unlocked by m.certState caller
-	m.state[ck] = state
-	return state, nil
-}
-
-// authorizedCert starts the domain ownership verification process and requests a new cert upon success.
-// The key argument is the certificate private key.
-func (m *Manager) authorizedCert(ctx context.Context, key crypto.Signer, ck certKey) (der [][]byte, leaf *x509.Certificate, err error) {
-	client, err := m.acmeClient(ctx)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	if err := m.verify(ctx, client, ck.domain); err != nil {
-		return nil, nil, err
-	}
-	csr, err := certRequest(key, ck.domain, m.ExtraExtensions)
-	if err != nil {
-		return nil, nil, err
-	}
-	der, _, err = client.CreateCert(ctx, csr, 0, true)
-	if err != nil {
-		return nil, nil, err
-	}
-	leaf, err = validCert(ck, der, key, m.now())
-	if err != nil {
-		return nil, nil, err
-	}
-	return der, leaf, nil
-}
-
-// revokePendingAuthz revokes all authorizations idenfied by the elements of uri slice.
-// It ignores revocation errors.
-func (m *Manager) revokePendingAuthz(ctx context.Context, uri []string) {
-	client, err := m.acmeClient(ctx)
-	if err != nil {
-		return
-	}
-	for _, u := range uri {
-		client.RevokeAuthorization(ctx, u)
-	}
-}
-
-// verify runs the identifier (domain) authorization flow
-// using each applicable ACME challenge type.
-func (m *Manager) verify(ctx context.Context, client *acme.Client, domain string) error {
-	// The list of challenge types we'll try to fulfill
-	// in this specific order.
-	challengeTypes := []string{"tls-alpn-01", "tls-sni-02", "tls-sni-01"}
-	m.tokensMu.RLock()
-	if m.tryHTTP01 {
-		challengeTypes = append(challengeTypes, "http-01")
-	}
-	m.tokensMu.RUnlock()
-
-	// Keep track of pending authzs and revoke the ones that did not validate.
-	pendingAuthzs := make(map[string]bool)
-	defer func() {
-		var uri []string
-		for k, pending := range pendingAuthzs {
-			if pending {
-				uri = append(uri, k)
-			}
-		}
-		if len(uri) > 0 {
-			// Use "detached" background context.
-			// The revocations need not happen in the current verification flow.
-			go m.revokePendingAuthz(context.Background(), uri)
-		}
-	}()
-
-	// errs accumulates challenge failure errors, printed if all fail
-	errs := make(map[*acme.Challenge]error)
-	var nextTyp int // challengeType index of the next challenge type to try
-	for {
-		// Start domain authorization and get the challenge.
-		authz, err := client.Authorize(ctx, domain)
-		if err != nil {
-			return err
-		}
-		// No point in accepting challenges if the authorization status
-		// is in a final state.
-		switch authz.Status {
-		case acme.StatusValid:
-			return nil // already authorized
-		case acme.StatusInvalid:
-			return fmt.Errorf("acme/autocert: invalid authorization %q", authz.URI)
-		}
-
-		pendingAuthzs[authz.URI] = true
-
-		// Pick the next preferred challenge.
-		var chal *acme.Challenge
-		for chal == nil && nextTyp < len(challengeTypes) {
-			chal = pickChallenge(challengeTypes[nextTyp], authz.Challenges)
-			nextTyp++
-		}
-		if chal == nil {
-			errorMsg := fmt.Sprintf("acme/autocert: unable to authorize %q", domain)
-			for chal, err := range errs {
-				errorMsg += fmt.Sprintf("; challenge %q failed with error: %v", chal.Type, err)
-			}
-			return errors.New(errorMsg)
-		}
-		cleanup, err := m.fulfill(ctx, client, chal, domain)
-		if err != nil {
-			errs[chal] = err
-			continue
-		}
-		defer cleanup()
-		if _, err := client.Accept(ctx, chal); err != nil {
-			errs[chal] = err
-			continue
-		}
-
-		// A challenge is fulfilled and accepted: wait for the CA to validate.
-		if _, err := client.WaitAuthorization(ctx, authz.URI); err != nil {
-			errs[chal] = err
-			continue
-		}
-		delete(pendingAuthzs, authz.URI)
-		return nil
-	}
-}
-
-// fulfill provisions a response to the challenge chal.
-// The cleanup is non-nil only if provisioning succeeded.
-func (m *Manager) fulfill(ctx context.Context, client *acme.Client, chal *acme.Challenge, domain string) (cleanup func(), err error) {
-	switch chal.Type {
-	case "tls-alpn-01":
-		cert, err := client.TLSALPN01ChallengeCert(chal.Token, domain)
-		if err != nil {
-			return nil, err
-		}
-		m.putCertToken(ctx, domain, &cert)
-		return func() { go m.deleteCertToken(domain) }, nil
-	case "tls-sni-01":
-		cert, name, err := client.TLSSNI01ChallengeCert(chal.Token)
-		if err != nil {
-			return nil, err
-		}
-		m.putCertToken(ctx, name, &cert)
-		return func() { go m.deleteCertToken(name) }, nil
-	case "tls-sni-02":
-		cert, name, err := client.TLSSNI02ChallengeCert(chal.Token)
-		if err != nil {
-			return nil, err
-		}
-		m.putCertToken(ctx, name, &cert)
-		return func() { go m.deleteCertToken(name) }, nil
-	case "http-01":
-		resp, err := client.HTTP01ChallengeResponse(chal.Token)
-		if err != nil {
-			return nil, err
-		}
-		p := client.HTTP01ChallengePath(chal.Token)
-		m.putHTTPToken(ctx, p, resp)
-		return func() { go m.deleteHTTPToken(p) }, nil
-	}
-	return nil, fmt.Errorf("acme/autocert: unknown challenge type %q", chal.Type)
-}
-
-func pickChallenge(typ string, chal []*acme.Challenge) *acme.Challenge {
-	for _, c := range chal {
-		if c.Type == typ {
-			return c
-		}
-	}
-	return nil
-}
-
-// putCertToken stores the token certificate with the specified name
-// in both m.certTokens map and m.Cache.
-func (m *Manager) putCertToken(ctx context.Context, name string, cert *tls.Certificate) {
-	m.tokensMu.Lock()
-	defer m.tokensMu.Unlock()
-	if m.certTokens == nil {
-		m.certTokens = make(map[string]*tls.Certificate)
-	}
-	m.certTokens[name] = cert
-	m.cachePut(ctx, certKey{domain: name, isToken: true}, cert)
-}
-
-// deleteCertToken removes the token certificate with the specified name
-// from both m.certTokens map and m.Cache.
-func (m *Manager) deleteCertToken(name string) {
-	m.tokensMu.Lock()
-	defer m.tokensMu.Unlock()
-	delete(m.certTokens, name)
-	if m.Cache != nil {
-		ck := certKey{domain: name, isToken: true}
-		m.Cache.Delete(context.Background(), ck.String())
-	}
-}
-
-// httpToken retrieves an existing http-01 token value from an in-memory map
-// or the optional cache.
-func (m *Manager) httpToken(ctx context.Context, tokenPath string) ([]byte, error) {
-	m.tokensMu.RLock()
-	defer m.tokensMu.RUnlock()
-	if v, ok := m.httpTokens[tokenPath]; ok {
-		return v, nil
-	}
-	if m.Cache == nil {
-		return nil, fmt.Errorf("acme/autocert: no token at %q", tokenPath)
-	}
-	return m.Cache.Get(ctx, httpTokenCacheKey(tokenPath))
-}
-
-// putHTTPToken stores an http-01 token value using tokenPath as key
-// in both in-memory map and the optional Cache.
-//
-// It ignores any error returned from Cache.Put.
-func (m *Manager) putHTTPToken(ctx context.Context, tokenPath, val string) {
-	m.tokensMu.Lock()
-	defer m.tokensMu.Unlock()
-	if m.httpTokens == nil {
-		m.httpTokens = make(map[string][]byte)
-	}
-	b := []byte(val)
-	m.httpTokens[tokenPath] = b
-	if m.Cache != nil {
-		m.Cache.Put(ctx, httpTokenCacheKey(tokenPath), b)
-	}
-}
-
-// deleteHTTPToken removes an http-01 token value from both in-memory map
-// and the optional Cache, ignoring any error returned from the latter.
-//
-// If m.Cache is non-nil, it blocks until Cache.Delete returns without a timeout.
-func (m *Manager) deleteHTTPToken(tokenPath string) {
-	m.tokensMu.Lock()
-	defer m.tokensMu.Unlock()
-	delete(m.httpTokens, tokenPath)
-	if m.Cache != nil {
-		m.Cache.Delete(context.Background(), httpTokenCacheKey(tokenPath))
-	}
-}
-
-// httpTokenCacheKey returns a key at which an http-01 token value may be stored
-// in the Manager's optional Cache.
-func httpTokenCacheKey(tokenPath string) string {
-	return path.Base(tokenPath) + "+http-01"
-}
-
-// renew starts a cert renewal timer loop, one per domain.
-//
-// The loop is scheduled in two cases:
-// - a cert was fetched from cache for the first time (wasn't in m.state)
-// - a new cert was created by m.createCert
-//
-// The key argument is a certificate private key.
-// The exp argument is the cert expiration time (NotAfter).
-func (m *Manager) renew(ck certKey, key crypto.Signer, exp time.Time) {
-	m.renewalMu.Lock()
-	defer m.renewalMu.Unlock()
-	if m.renewal[ck] != nil {
-		// another goroutine is already on it
-		return
-	}
-	if m.renewal == nil {
-		m.renewal = make(map[certKey]*domainRenewal)
-	}
-	dr := &domainRenewal{m: m, ck: ck, key: key}
-	m.renewal[ck] = dr
-	dr.start(exp)
-}
-
-// stopRenew stops all currently running cert renewal timers.
-// The timers are not restarted during the lifetime of the Manager.
-func (m *Manager) stopRenew() {
-	m.renewalMu.Lock()
-	defer m.renewalMu.Unlock()
-	for name, dr := range m.renewal {
-		delete(m.renewal, name)
-		dr.stop()
-	}
-}
-
-func (m *Manager) accountKey(ctx context.Context) (crypto.Signer, error) {
-	const keyName = "acme_account+key"
-
-	// Previous versions of autocert stored the value under a different key.
-	const legacyKeyName = "acme_account.key"
-
-	genKey := func() (*ecdsa.PrivateKey, error) {
-		return ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
-	}
-
-	if m.Cache == nil {
-		return genKey()
-	}
-
-	data, err := m.Cache.Get(ctx, keyName)
-	if err == ErrCacheMiss {
-		data, err = m.Cache.Get(ctx, legacyKeyName)
-	}
-	if err == ErrCacheMiss {
-		key, err := genKey()
-		if err != nil {
-			return nil, err
-		}
-		var buf bytes.Buffer
-		if err := encodeECDSAKey(&buf, key); err != nil {
-			return nil, err
-		}
-		if err := m.Cache.Put(ctx, keyName, buf.Bytes()); err != nil {
-			return nil, err
-		}
-		return key, nil
-	}
-	if err != nil {
-		return nil, err
-	}
-
-	priv, _ := pem.Decode(data)
-	if priv == nil || !strings.Contains(priv.Type, "PRIVATE") {
-		return nil, errors.New("acme/autocert: invalid account key found in cache")
-	}
-	return parsePrivateKey(priv.Bytes)
-}
-
-func (m *Manager) acmeClient(ctx context.Context) (*acme.Client, error) {
-	m.clientMu.Lock()
-	defer m.clientMu.Unlock()
-	if m.client != nil {
-		return m.client, nil
-	}
-
-	client := m.Client
-	if client == nil {
-		client = &acme.Client{DirectoryURL: acme.LetsEncryptURL}
-	}
-	if client.Key == nil {
-		var err error
-		client.Key, err = m.accountKey(ctx)
-		if err != nil {
-			return nil, err
-		}
-	}
-	var contact []string
-	if m.Email != "" {
-		contact = []string{"mailto:" + m.Email}
-	}
-	a := &acme.Account{Contact: contact}
-	_, err := client.Register(ctx, a, m.Prompt)
-	if ae, ok := err.(*acme.Error); err == nil || ok && ae.StatusCode == http.StatusConflict {
-		// conflict indicates the key is already registered
-		m.client = client
-		err = nil
-	}
-	return m.client, err
-}
-
-func (m *Manager) hostPolicy() HostPolicy {
-	if m.HostPolicy != nil {
-		return m.HostPolicy
-	}
-	return defaultHostPolicy
-}
-
-func (m *Manager) renewBefore() time.Duration {
-	if m.RenewBefore > renewJitter {
-		return m.RenewBefore
-	}
-	return 720 * time.Hour // 30 days
-}
-
-func (m *Manager) now() time.Time {
-	if m.nowFunc != nil {
-		return m.nowFunc()
-	}
-	return time.Now()
-}
-
-// certState is ready when its mutex is unlocked for reading.
-type certState struct {
-	sync.RWMutex
-	locked bool              // locked for read/write
-	key    crypto.Signer     // private key for cert
-	cert   [][]byte          // DER encoding
-	leaf   *x509.Certificate // parsed cert[0]; always non-nil if cert != nil
-}
-
-// tlscert creates a tls.Certificate from s.key and s.cert.
-// Callers should wrap it in s.RLock() and s.RUnlock().
-func (s *certState) tlscert() (*tls.Certificate, error) {
-	if s.key == nil {
-		return nil, errors.New("acme/autocert: missing signer")
-	}
-	if len(s.cert) == 0 {
-		return nil, errors.New("acme/autocert: missing certificate")
-	}
-	return &tls.Certificate{
-		PrivateKey:  s.key,
-		Certificate: s.cert,
-		Leaf:        s.leaf,
-	}, nil
-}
-
-// certRequest generates a CSR for the given common name cn and optional SANs.
-func certRequest(key crypto.Signer, cn string, ext []pkix.Extension, san ...string) ([]byte, error) {
-	req := &x509.CertificateRequest{
-		Subject:         pkix.Name{CommonName: cn},
-		DNSNames:        san,
-		ExtraExtensions: ext,
-	}
-	return x509.CreateCertificateRequest(rand.Reader, req, key)
-}
-
-// Attempt to parse the given private key DER block. OpenSSL 0.9.8 generates
-// PKCS#1 private keys by default, while OpenSSL 1.0.0 generates PKCS#8 keys.
-// OpenSSL ecparam generates SEC1 EC private keys for ECDSA. We try all three.
-//
-// Inspired by parsePrivateKey in crypto/tls/tls.go.
-func parsePrivateKey(der []byte) (crypto.Signer, error) {
-	if key, err := x509.ParsePKCS1PrivateKey(der); err == nil {
-		return key, nil
-	}
-	if key, err := x509.ParsePKCS8PrivateKey(der); err == nil {
-		switch key := key.(type) {
-		case *rsa.PrivateKey:
-			return key, nil
-		case *ecdsa.PrivateKey:
-			return key, nil
-		default:
-			return nil, errors.New("acme/autocert: unknown private key type in PKCS#8 wrapping")
-		}
-	}
-	if key, err := x509.ParseECPrivateKey(der); err == nil {
-		return key, nil
-	}
-
-	return nil, errors.New("acme/autocert: failed to parse private key")
-}
-
-// validCert parses a cert chain provided as der argument and verifies the leaf and der[0]
-// correspond to the private key, the domain and key type match, and expiration dates
-// are valid. It doesn't do any revocation checking.
-//
-// The returned value is the verified leaf cert.
-func validCert(ck certKey, der [][]byte, key crypto.Signer, now time.Time) (leaf *x509.Certificate, err error) {
-	// parse public part(s)
-	var n int
-	for _, b := range der {
-		n += len(b)
-	}
-	pub := make([]byte, n)
-	n = 0
-	for _, b := range der {
-		n += copy(pub[n:], b)
-	}
-	x509Cert, err := x509.ParseCertificates(pub)
-	if err != nil || len(x509Cert) == 0 {
-		return nil, errors.New("acme/autocert: no public key found")
-	}
-	// verify the leaf is not expired and matches the domain name
-	leaf = x509Cert[0]
-	if now.Before(leaf.NotBefore) {
-		return nil, errors.New("acme/autocert: certificate is not valid yet")
-	}
-	if now.After(leaf.NotAfter) {
-		return nil, errors.New("acme/autocert: expired certificate")
-	}
-	if err := leaf.VerifyHostname(ck.domain); err != nil {
-		return nil, err
-	}
-	// ensure the leaf corresponds to the private key and matches the certKey type
-	switch pub := leaf.PublicKey.(type) {
-	case *rsa.PublicKey:
-		prv, ok := key.(*rsa.PrivateKey)
-		if !ok {
-			return nil, errors.New("acme/autocert: private key type does not match public key type")
-		}
-		if pub.N.Cmp(prv.N) != 0 {
-			return nil, errors.New("acme/autocert: private key does not match public key")
-		}
-		if !ck.isRSA && !ck.isToken {
-			return nil, errors.New("acme/autocert: key type does not match expected value")
-		}
-	case *ecdsa.PublicKey:
-		prv, ok := key.(*ecdsa.PrivateKey)
-		if !ok {
-			return nil, errors.New("acme/autocert: private key type does not match public key type")
-		}
-		if pub.X.Cmp(prv.X) != 0 || pub.Y.Cmp(prv.Y) != 0 {
-			return nil, errors.New("acme/autocert: private key does not match public key")
-		}
-		if ck.isRSA && !ck.isToken {
-			return nil, errors.New("acme/autocert: key type does not match expected value")
-		}
-	default:
-		return nil, errors.New("acme/autocert: unknown public key algorithm")
-	}
-	return leaf, nil
-}
-
-type lockedMathRand struct {
-	sync.Mutex
-	rnd *mathrand.Rand
-}
-
-func (r *lockedMathRand) int63n(max int64) int64 {
-	r.Lock()
-	n := r.rnd.Int63n(max)
-	r.Unlock()
-	return n
-}
-
-// For easier testing.
-var (
-	// Called when a state is removed.
-	testDidRemoveState = func(certKey) {}
-)
diff --git a/vendor/golang.org/x/crypto/acme/autocert/cache.go b/vendor/golang.org/x/crypto/acme/autocert/cache.go
deleted file mode 100644
index aa9aa84..0000000
--- a/vendor/golang.org/x/crypto/acme/autocert/cache.go
+++ /dev/null
@@ -1,130 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package autocert
-
-import (
-	"context"
-	"errors"
-	"io/ioutil"
-	"os"
-	"path/filepath"
-)
-
-// ErrCacheMiss is returned when a certificate is not found in cache.
-var ErrCacheMiss = errors.New("acme/autocert: certificate cache miss")
-
-// Cache is used by Manager to store and retrieve previously obtained certificates
-// and other account data as opaque blobs.
-//
-// Cache implementations should not rely on the key naming pattern. Keys can
-// include any printable ASCII characters, except the following: \/:*?"<>|
-type Cache interface {
-	// Get returns a certificate data for the specified key.
-	// If there's no such key, Get returns ErrCacheMiss.
-	Get(ctx context.Context, key string) ([]byte, error)
-
-	// Put stores the data in the cache under the specified key.
-	// Underlying implementations may use any data storage format,
-	// as long as the reverse operation, Get, results in the original data.
-	Put(ctx context.Context, key string, data []byte) error
-
-	// Delete removes a certificate data from the cache under the specified key.
-	// If there's no such key in the cache, Delete returns nil.
-	Delete(ctx context.Context, key string) error
-}
-
-// DirCache implements Cache using a directory on the local filesystem.
-// If the directory does not exist, it will be created with 0700 permissions.
-type DirCache string
-
-// Get reads a certificate data from the specified file name.
-func (d DirCache) Get(ctx context.Context, name string) ([]byte, error) {
-	name = filepath.Join(string(d), name)
-	var (
-		data []byte
-		err  error
-		done = make(chan struct{})
-	)
-	go func() {
-		data, err = ioutil.ReadFile(name)
-		close(done)
-	}()
-	select {
-	case <-ctx.Done():
-		return nil, ctx.Err()
-	case <-done:
-	}
-	if os.IsNotExist(err) {
-		return nil, ErrCacheMiss
-	}
-	return data, err
-}
-
-// Put writes the certificate data to the specified file name.
-// The file will be created with 0600 permissions.
-func (d DirCache) Put(ctx context.Context, name string, data []byte) error {
-	if err := os.MkdirAll(string(d), 0700); err != nil {
-		return err
-	}
-
-	done := make(chan struct{})
-	var err error
-	go func() {
-		defer close(done)
-		var tmp string
-		if tmp, err = d.writeTempFile(name, data); err != nil {
-			return
-		}
-		select {
-		case <-ctx.Done():
-			// Don't overwrite the file if the context was canceled.
-		default:
-			newName := filepath.Join(string(d), name)
-			err = os.Rename(tmp, newName)
-		}
-	}()
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-done:
-	}
-	return err
-}
-
-// Delete removes the specified file name.
-func (d DirCache) Delete(ctx context.Context, name string) error {
-	name = filepath.Join(string(d), name)
-	var (
-		err  error
-		done = make(chan struct{})
-	)
-	go func() {
-		err = os.Remove(name)
-		close(done)
-	}()
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-done:
-	}
-	if err != nil && !os.IsNotExist(err) {
-		return err
-	}
-	return nil
-}
-
-// writeTempFile writes b to a temporary file, closes the file and returns its path.
-func (d DirCache) writeTempFile(prefix string, b []byte) (string, error) {
-	// TempFile uses 0600 permissions
-	f, err := ioutil.TempFile(string(d), prefix)
-	if err != nil {
-		return "", err
-	}
-	if _, err := f.Write(b); err != nil {
-		f.Close()
-		return "", err
-	}
-	return f.Name(), f.Close()
-}
diff --git a/vendor/golang.org/x/crypto/acme/autocert/listener.go b/vendor/golang.org/x/crypto/acme/autocert/listener.go
deleted file mode 100644
index 1e06981..0000000
--- a/vendor/golang.org/x/crypto/acme/autocert/listener.go
+++ /dev/null
@@ -1,157 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package autocert
-
-import (
-	"crypto/tls"
-	"log"
-	"net"
-	"os"
-	"path/filepath"
-	"runtime"
-	"time"
-)
-
-// NewListener returns a net.Listener that listens on the standard TLS
-// port (443) on all interfaces and returns *tls.Conn connections with
-// LetsEncrypt certificates for the provided domain or domains.
-//
-// It enables one-line HTTPS servers:
-//
-//     log.Fatal(http.Serve(autocert.NewListener("example.com"), handler))
-//
-// NewListener is a convenience function for a common configuration.
-// More complex or custom configurations can use the autocert.Manager
-// type instead.
-//
-// Use of this function implies acceptance of the LetsEncrypt Terms of
-// Service. If domains is not empty, the provided domains are passed
-// to HostWhitelist. If domains is empty, the listener will do
-// LetsEncrypt challenges for any requested domain, which is not
-// recommended.
-//
-// Certificates are cached in a "golang-autocert" directory under an
-// operating system-specific cache or temp directory. This may not
-// be suitable for servers spanning multiple machines.
-//
-// The returned listener uses a *tls.Config that enables HTTP/2, and
-// should only be used with servers that support HTTP/2.
-//
-// The returned Listener also enables TCP keep-alives on the accepted
-// connections. The returned *tls.Conn are returned before their TLS
-// handshake has completed.
-func NewListener(domains ...string) net.Listener {
-	m := &Manager{
-		Prompt: AcceptTOS,
-	}
-	if len(domains) > 0 {
-		m.HostPolicy = HostWhitelist(domains...)
-	}
-	dir := cacheDir()
-	if err := os.MkdirAll(dir, 0700); err != nil {
-		log.Printf("warning: autocert.NewListener not using a cache: %v", err)
-	} else {
-		m.Cache = DirCache(dir)
-	}
-	return m.Listener()
-}
-
-// Listener listens on the standard TLS port (443) on all interfaces
-// and returns a net.Listener returning *tls.Conn connections.
-//
-// The returned listener uses a *tls.Config that enables HTTP/2, and
-// should only be used with servers that support HTTP/2.
-//
-// The returned Listener also enables TCP keep-alives on the accepted
-// connections. The returned *tls.Conn are returned before their TLS
-// handshake has completed.
-//
-// Unlike NewListener, it is the caller's responsibility to initialize
-// the Manager m's Prompt, Cache, HostPolicy, and other desired options.
-func (m *Manager) Listener() net.Listener {
-	ln := &listener{
-		m:    m,
-		conf: m.TLSConfig(),
-	}
-	ln.tcpListener, ln.tcpListenErr = net.Listen("tcp", ":443")
-	return ln
-}
-
-type listener struct {
-	m    *Manager
-	conf *tls.Config
-
-	tcpListener  net.Listener
-	tcpListenErr error
-}
-
-func (ln *listener) Accept() (net.Conn, error) {
-	if ln.tcpListenErr != nil {
-		return nil, ln.tcpListenErr
-	}
-	conn, err := ln.tcpListener.Accept()
-	if err != nil {
-		return nil, err
-	}
-	tcpConn := conn.(*net.TCPConn)
-
-	// Because Listener is a convenience function, help out with
-	// this too.  This is not possible for the caller to set once
-	// we return a *tcp.Conn wrapping an inaccessible net.Conn.
-	// If callers don't want this, they can do things the manual
-	// way and tweak as needed. But this is what net/http does
-	// itself, so copy that. If net/http changes, we can change
-	// here too.
-	tcpConn.SetKeepAlive(true)
-	tcpConn.SetKeepAlivePeriod(3 * time.Minute)
-
-	return tls.Server(tcpConn, ln.conf), nil
-}
-
-func (ln *listener) Addr() net.Addr {
-	if ln.tcpListener != nil {
-		return ln.tcpListener.Addr()
-	}
-	// net.Listen failed. Return something non-nil in case callers
-	// call Addr before Accept:
-	return &net.TCPAddr{IP: net.IP{0, 0, 0, 0}, Port: 443}
-}
-
-func (ln *listener) Close() error {
-	if ln.tcpListenErr != nil {
-		return ln.tcpListenErr
-	}
-	return ln.tcpListener.Close()
-}
-
-func homeDir() string {
-	if runtime.GOOS == "windows" {
-		return os.Getenv("HOMEDRIVE") + os.Getenv("HOMEPATH")
-	}
-	if h := os.Getenv("HOME"); h != "" {
-		return h
-	}
-	return "/"
-}
-
-func cacheDir() string {
-	const base = "golang-autocert"
-	switch runtime.GOOS {
-	case "darwin":
-		return filepath.Join(homeDir(), "Library", "Caches", base)
-	case "windows":
-		for _, ev := range []string{"APPDATA", "CSIDL_APPDATA", "TEMP", "TMP"} {
-			if v := os.Getenv(ev); v != "" {
-				return filepath.Join(v, base)
-			}
-		}
-		// Worst case:
-		return filepath.Join(homeDir(), base)
-	}
-	if xdg := os.Getenv("XDG_CACHE_HOME"); xdg != "" {
-		return filepath.Join(xdg, base)
-	}
-	return filepath.Join(homeDir(), ".cache", base)
-}
diff --git a/vendor/golang.org/x/crypto/acme/autocert/renewal.go b/vendor/golang.org/x/crypto/acme/autocert/renewal.go
deleted file mode 100644
index 665f870..0000000
--- a/vendor/golang.org/x/crypto/acme/autocert/renewal.go
+++ /dev/null
@@ -1,141 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package autocert
-
-import (
-	"context"
-	"crypto"
-	"sync"
-	"time"
-)
-
-// renewJitter is the maximum deviation from Manager.RenewBefore.
-const renewJitter = time.Hour
-
-// domainRenewal tracks the state used by the periodic timers
-// renewing a single domain's cert.
-type domainRenewal struct {
-	m   *Manager
-	ck  certKey
-	key crypto.Signer
-
-	timerMu sync.Mutex
-	timer   *time.Timer
-}
-
-// start starts a cert renewal timer at the time
-// defined by the certificate expiration time exp.
-//
-// If the timer is already started, calling start is a noop.
-func (dr *domainRenewal) start(exp time.Time) {
-	dr.timerMu.Lock()
-	defer dr.timerMu.Unlock()
-	if dr.timer != nil {
-		return
-	}
-	dr.timer = time.AfterFunc(dr.next(exp), dr.renew)
-}
-
-// stop stops the cert renewal timer.
-// If the timer is already stopped, calling stop is a noop.
-func (dr *domainRenewal) stop() {
-	dr.timerMu.Lock()
-	defer dr.timerMu.Unlock()
-	if dr.timer == nil {
-		return
-	}
-	dr.timer.Stop()
-	dr.timer = nil
-}
-
-// renew is called periodically by a timer.
-// The first renew call is kicked off by dr.start.
-func (dr *domainRenewal) renew() {
-	dr.timerMu.Lock()
-	defer dr.timerMu.Unlock()
-	if dr.timer == nil {
-		return
-	}
-
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Minute)
-	defer cancel()
-	// TODO: rotate dr.key at some point?
-	next, err := dr.do(ctx)
-	if err != nil {
-		next = renewJitter / 2
-		next += time.Duration(pseudoRand.int63n(int64(next)))
-	}
-	dr.timer = time.AfterFunc(next, dr.renew)
-	testDidRenewLoop(next, err)
-}
-
-// updateState locks and replaces the relevant Manager.state item with the given
-// state. It additionally updates dr.key with the given state's key.
-func (dr *domainRenewal) updateState(state *certState) {
-	dr.m.stateMu.Lock()
-	defer dr.m.stateMu.Unlock()
-	dr.key = state.key
-	dr.m.state[dr.ck] = state
-}
-
-// do is similar to Manager.createCert but it doesn't lock a Manager.state item.
-// Instead, it requests a new certificate independently and, upon success,
-// replaces dr.m.state item with a new one and updates cache for the given domain.
-//
-// It may lock and update the Manager.state if the expiration date of the currently
-// cached cert is far enough in the future.
-//
-// The returned value is a time interval after which the renewal should occur again.
-func (dr *domainRenewal) do(ctx context.Context) (time.Duration, error) {
-	// a race is likely unavoidable in a distributed environment
-	// but we try nonetheless
-	if tlscert, err := dr.m.cacheGet(ctx, dr.ck); err == nil {
-		next := dr.next(tlscert.Leaf.NotAfter)
-		if next > dr.m.renewBefore()+renewJitter {
-			signer, ok := tlscert.PrivateKey.(crypto.Signer)
-			if ok {
-				state := &certState{
-					key:  signer,
-					cert: tlscert.Certificate,
-					leaf: tlscert.Leaf,
-				}
-				dr.updateState(state)
-				return next, nil
-			}
-		}
-	}
-
-	der, leaf, err := dr.m.authorizedCert(ctx, dr.key, dr.ck)
-	if err != nil {
-		return 0, err
-	}
-	state := &certState{
-		key:  dr.key,
-		cert: der,
-		leaf: leaf,
-	}
-	tlscert, err := state.tlscert()
-	if err != nil {
-		return 0, err
-	}
-	if err := dr.m.cachePut(ctx, dr.ck, tlscert); err != nil {
-		return 0, err
-	}
-	dr.updateState(state)
-	return dr.next(leaf.NotAfter), nil
-}
-
-func (dr *domainRenewal) next(expiry time.Time) time.Duration {
-	d := expiry.Sub(dr.m.now()) - dr.m.renewBefore()
-	// add a bit of randomness to renew deadline
-	n := pseudoRand.int63n(int64(renewJitter))
-	d -= time.Duration(n)
-	if d < 0 {
-		return 0
-	}
-	return d
-}
-
-var testDidRenewLoop = func(next time.Duration, err error) {}