更新

vendor/golang.org/x/crypto/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/golang.org/x/crypto/PATENTS

@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go.  This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation.  If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.

vendor/golang.org/x/crypto/acme/acme.go

@@ -0,0 +1,1102 @@
+// Copyright 2015 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 acme provides an implementation of the
+// Automatic Certificate Management Environment (ACME) spec.
+// The intial implementation was based on ACME draft-02 and
+// is now being extended to comply with RFC 8555.
+// See https://tools.ietf.org/html/draft-ietf-acme-acme-02
+// and https://tools.ietf.org/html/rfc8555 for details.
+//
+// Most common scenarios will want to use autocert subdirectory instead,
+// which 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 acme
+
+import (
+	"context"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/sha256"
+	"crypto/tls"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/asn1"
+	"encoding/base64"
+	"encoding/hex"
+	"encoding/json"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"math/big"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	// LetsEncryptURL is the Directory endpoint of Let's Encrypt CA.
+	LetsEncryptURL = "https://acme-v02.api.letsencrypt.org/directory"
+
+	// ALPNProto is the ALPN protocol name used by a CA server when validating
+	// tls-alpn-01 challenges.
+	//
+	// Package users must ensure their servers can negotiate the ACME ALPN in
+	// order for tls-alpn-01 challenge verifications to succeed.
+	// See the crypto/tls package's Config.NextProtos field.
+	ALPNProto = "acme-tls/1"
+)
+
+// idPeACMEIdentifier is the OID for the ACME extension for the TLS-ALPN challenge.
+// https://tools.ietf.org/html/draft-ietf-acme-tls-alpn-05#section-5.1
+var idPeACMEIdentifier = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 1, 31}
+
+const (
+	maxChainLen = 5       // max depth and breadth of a certificate chain
+	maxCertSize = 1 << 20 // max size of a certificate, in DER bytes
+	// Used for decoding certs from application/pem-certificate-chain response,
+	// the default when in RFC mode.
+	maxCertChainSize = maxCertSize * maxChainLen
+
+	// Max number of collected nonces kept in memory.
+	// Expect usual peak of 1 or 2.
+	maxNonces = 100
+)
+
+// Client is an ACME client.
+// The only required field is Key. An example of creating a client with a new key
+// is as follows:
+//
+// 	key, err := rsa.GenerateKey(rand.Reader, 2048)
+// 	if err != nil {
+// 		log.Fatal(err)
+// 	}
+// 	client := &Client{Key: key}
+//
+type Client struct {
+	// Key is the account key used to register with a CA and sign requests.
+	// Key.Public() must return a *rsa.PublicKey or *ecdsa.PublicKey.
+	//
+	// The following algorithms are supported:
+	// RS256, ES256, ES384 and ES512.
+	// See RFC7518 for more details about the algorithms.
+	Key crypto.Signer
+
+	// HTTPClient optionally specifies an HTTP client to use
+	// instead of http.DefaultClient.
+	HTTPClient *http.Client
+
+	// DirectoryURL points to the CA directory endpoint.
+	// If empty, LetsEncryptURL is used.
+	// Mutating this value after a successful call of Client's Discover method
+	// will have no effect.
+	DirectoryURL string
+
+	// RetryBackoff computes the duration after which the nth retry of a failed request
+	// should occur. The value of n for the first call on failure is 1.
+	// The values of r and resp are the request and response of the last failed attempt.
+	// If the returned value is negative or zero, no more retries are done and an error
+	// is returned to the caller of the original method.
+	//
+	// Requests which result in a 4xx client error are not retried,
+	// except for 400 Bad Request due to "bad nonce" errors and 429 Too Many Requests.
+	//
+	// If RetryBackoff is nil, a truncated exponential backoff algorithm
+	// with the ceiling of 10 seconds is used, where each subsequent retry n
+	// is done after either ("Retry-After" + jitter) or (2^n seconds + jitter),
+	// preferring the former if "Retry-After" header is found in the resp.
+	// The jitter is a random value up to 1 second.
+	RetryBackoff func(n int, r *http.Request, resp *http.Response) time.Duration
+
+	// UserAgent is prepended to the User-Agent header sent to the ACME server,
+	// which by default is this package's name and version.
+	//
+	// Reusable libraries and tools in particular should set this value to be
+	// identifiable by the server, in case they are causing issues.
+	UserAgent string
+
+	cacheMu sync.Mutex
+	dir     *Directory // cached result of Client's Discover method
+	kid     keyID      // cached Account.URI obtained from registerRFC or getAccountRFC
+
+	noncesMu sync.Mutex
+	nonces   map[string]struct{} // nonces collected from previous responses
+}
+
+// accountKID returns a key ID associated with c.Key, the account identity
+// provided by the CA during RFC based registration.
+// It assumes c.Discover has already been called.
+//
+// accountKID requires at most one network roundtrip.
+// It caches only successful result.
+//
+// When in pre-RFC mode or when c.getRegRFC responds with an error, accountKID
+// returns noKeyID.
+func (c *Client) accountKID(ctx context.Context) keyID {
+	c.cacheMu.Lock()
+	defer c.cacheMu.Unlock()
+	if !c.dir.rfcCompliant() {
+		return noKeyID
+	}
+	if c.kid != noKeyID {
+		return c.kid
+	}
+	a, err := c.getRegRFC(ctx)
+	if err != nil {
+		return noKeyID
+	}
+	c.kid = keyID(a.URI)
+	return c.kid
+}
+
+// Discover performs ACME server discovery using c.DirectoryURL.
+//
+// It caches successful result. So, subsequent calls will not result in
+// a network round-trip. This also means mutating c.DirectoryURL after successful call
+// of this method will have no effect.
+func (c *Client) Discover(ctx context.Context) (Directory, error) {
+	c.cacheMu.Lock()
+	defer c.cacheMu.Unlock()
+	if c.dir != nil {
+		return *c.dir, nil
+	}
+
+	res, err := c.get(ctx, c.directoryURL(), wantStatus(http.StatusOK))
+	if err != nil {
+		return Directory{}, err
+	}
+	defer res.Body.Close()
+	c.addNonce(res.Header)
+
+	var v struct {
+		Reg          string `json:"new-reg"`
+		RegRFC       string `json:"newAccount"`
+		Authz        string `json:"new-authz"`
+		AuthzRFC     string `json:"newAuthz"`
+		OrderRFC     string `json:"newOrder"`
+		Cert         string `json:"new-cert"`
+		Revoke       string `json:"revoke-cert"`
+		RevokeRFC    string `json:"revokeCert"`
+		NonceRFC     string `json:"newNonce"`
+		KeyChangeRFC string `json:"keyChange"`
+		Meta         struct {
+			Terms           string   `json:"terms-of-service"`
+			TermsRFC        string   `json:"termsOfService"`
+			WebsiteRFC      string   `json:"website"`
+			CAA             []string `json:"caa-identities"`
+			CAARFC          []string `json:"caaIdentities"`
+			ExternalAcctRFC bool     `json:"externalAccountRequired"`
+		}
+	}
+	if err := json.NewDecoder(res.Body).Decode(&v); err != nil {
+		return Directory{}, err
+	}
+	if v.OrderRFC == "" {
+		// Non-RFC compliant ACME CA.
+		c.dir = &Directory{
+			RegURL:    v.Reg,
+			AuthzURL:  v.Authz,
+			CertURL:   v.Cert,
+			RevokeURL: v.Revoke,
+			Terms:     v.Meta.Terms,
+			Website:   v.Meta.WebsiteRFC,
+			CAA:       v.Meta.CAA,
+		}
+		return *c.dir, nil
+	}
+	// RFC compliant ACME CA.
+	c.dir = &Directory{
+		RegURL:                  v.RegRFC,
+		AuthzURL:                v.AuthzRFC,
+		OrderURL:                v.OrderRFC,
+		RevokeURL:               v.RevokeRFC,
+		NonceURL:                v.NonceRFC,
+		KeyChangeURL:            v.KeyChangeRFC,
+		Terms:                   v.Meta.TermsRFC,
+		Website:                 v.Meta.WebsiteRFC,
+		CAA:                     v.Meta.CAARFC,
+		ExternalAccountRequired: v.Meta.ExternalAcctRFC,
+	}
+	return *c.dir, nil
+}
+
+func (c *Client) directoryURL() string {
+	if c.DirectoryURL != "" {
+		return c.DirectoryURL
+	}
+	return LetsEncryptURL
+}
+
+// CreateCert requests a new certificate using the Certificate Signing Request csr encoded in DER format.
+// It is incompatible with RFC 8555. Callers should use CreateOrderCert when interfacing
+// with an RFC-compliant CA.
+//
+// The exp argument indicates the desired certificate validity duration. CA may issue a certificate
+// with a different duration.
+// If the bundle argument is true, the returned value will also contain the CA (issuer) certificate chain.
+//
+// In the case where CA server does not provide the issued certificate in the response,
+// CreateCert will poll certURL using c.FetchCert, which will result in additional round-trips.
+// In such a scenario, the caller can cancel the polling with ctx.
+//
+// CreateCert returns an error if the CA's response or chain was unreasonably large.
+// Callers are encouraged to parse the returned value to ensure the certificate is valid and has the expected features.
+func (c *Client) CreateCert(ctx context.Context, csr []byte, exp time.Duration, bundle bool) (der [][]byte, certURL string, err error) {
+	if _, err := c.Discover(ctx); err != nil {
+		return nil, "", err
+	}
+
+	req := struct {
+		Resource  string `json:"resource"`
+		CSR       string `json:"csr"`
+		NotBefore string `json:"notBefore,omitempty"`
+		NotAfter  string `json:"notAfter,omitempty"`
+	}{
+		Resource: "new-cert",
+		CSR:      base64.RawURLEncoding.EncodeToString(csr),
+	}
+	now := timeNow()
+	req.NotBefore = now.Format(time.RFC3339)
+	if exp > 0 {
+		req.NotAfter = now.Add(exp).Format(time.RFC3339)
+	}
+
+	res, err := c.post(ctx, nil, c.dir.CertURL, req, wantStatus(http.StatusCreated))
+	if err != nil {
+		return nil, "", err
+	}
+	defer res.Body.Close()
+
+	curl := res.Header.Get("Location") // cert permanent URL
+	if res.ContentLength == 0 {
+		// no cert in the body; poll until we get it
+		cert, err := c.FetchCert(ctx, curl, bundle)
+		return cert, curl, err
+	}
+	// slurp issued cert and CA chain, if requested
+	cert, err := c.responseCert(ctx, res, bundle)
+	return cert, curl, err
+}
+
+// FetchCert retrieves already issued certificate from the given url, in DER format.
+// It retries the request until the certificate is successfully retrieved,
+// context is cancelled by the caller or an error response is received.
+//
+// If the bundle argument is true, the returned value also contains the CA (issuer)
+// certificate chain.
+//
+// FetchCert returns an error if the CA's response or chain was unreasonably large.
+// Callers are encouraged to parse the returned value to ensure the certificate is valid
+// and has expected features.
+func (c *Client) FetchCert(ctx context.Context, url string, bundle bool) ([][]byte, error) {
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+	if dir.rfcCompliant() {
+		return c.fetchCertRFC(ctx, url, bundle)
+	}
+
+	// Legacy non-authenticated GET request.
+	res, err := c.get(ctx, url, wantStatus(http.StatusOK))
+	if err != nil {
+		return nil, err
+	}
+	return c.responseCert(ctx, res, bundle)
+}
+
+// RevokeCert revokes a previously issued certificate cert, provided in DER format.
+//
+// The key argument, used to sign the request, must be authorized
+// to revoke the certificate. It's up to the CA to decide which keys are authorized.
+// For instance, the key pair of the certificate may be authorized.
+// If the key is nil, c.Key is used instead.
+func (c *Client) RevokeCert(ctx context.Context, key crypto.Signer, cert []byte, reason CRLReasonCode) error {
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return err
+	}
+	if dir.rfcCompliant() {
+		return c.revokeCertRFC(ctx, key, cert, reason)
+	}
+
+	// Legacy CA.
+	body := &struct {
+		Resource string `json:"resource"`
+		Cert     string `json:"certificate"`
+		Reason   int    `json:"reason"`
+	}{
+		Resource: "revoke-cert",
+		Cert:     base64.RawURLEncoding.EncodeToString(cert),
+		Reason:   int(reason),
+	}
+	res, err := c.post(ctx, key, dir.RevokeURL, body, wantStatus(http.StatusOK))
+	if err != nil {
+		return err
+	}
+	defer res.Body.Close()
+	return nil
+}
+
+// AcceptTOS always returns true to indicate the acceptance of a CA's Terms of Service
+// during account registration. See Register method of Client for more details.
+func AcceptTOS(tosURL string) bool { return true }
+
+// Register creates a new account with the CA using c.Key.
+// It returns the registered account. The account acct is not modified.
+//
+// The registration may require the caller to agree to the CA's Terms of Service (TOS).
+// If so, and the account has not indicated the acceptance of the terms (see Account for details),
+// Register 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 caller can use AcceptTOS.
+//
+// When interfacing with an RFC-compliant CA, non-RFC 8555 fields of acct are ignored
+// and prompt is called if Directory's Terms field is non-zero.
+// Also see Error's Instance field for when a CA requires already registered accounts to agree
+// to an updated Terms of Service.
+func (c *Client) Register(ctx context.Context, acct *Account, prompt func(tosURL string) bool) (*Account, error) {
+	if c.Key == nil {
+		return nil, errors.New("acme: client.Key must be set to Register")
+	}
+
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+	if dir.rfcCompliant() {
+		return c.registerRFC(ctx, acct, prompt)
+	}
+
+	// Legacy ACME draft registration flow.
+	a, err := c.doReg(ctx, dir.RegURL, "new-reg", acct)
+	if err != nil {
+		return nil, err
+	}
+	var accept bool
+	if a.CurrentTerms != "" && a.CurrentTerms != a.AgreedTerms {
+		accept = prompt(a.CurrentTerms)
+	}
+	if accept {
+		a.AgreedTerms = a.CurrentTerms
+		a, err = c.UpdateReg(ctx, a)
+	}
+	return a, err
+}
+
+// GetReg retrieves an existing account associated with c.Key.
+//
+// The url argument is an Account URI used with pre-RFC 8555 CAs.
+// It is ignored when interfacing with an RFC-compliant CA.
+func (c *Client) GetReg(ctx context.Context, url string) (*Account, error) {
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+	if dir.rfcCompliant() {
+		return c.getRegRFC(ctx)
+	}
+
+	// Legacy CA.
+	a, err := c.doReg(ctx, url, "reg", nil)
+	if err != nil {
+		return nil, err
+	}
+	a.URI = url
+	return a, nil
+}
+
+// UpdateReg updates an existing registration.
+// It returns an updated account copy. The provided account is not modified.
+//
+// When interfacing with RFC-compliant CAs, a.URI is ignored and the account URL
+// associated with c.Key is used instead.
+func (c *Client) UpdateReg(ctx context.Context, acct *Account) (*Account, error) {
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+	if dir.rfcCompliant() {
+		return c.updateRegRFC(ctx, acct)
+	}
+
+	// Legacy CA.
+	uri := acct.URI
+	a, err := c.doReg(ctx, uri, "reg", acct)
+	if err != nil {
+		return nil, err
+	}
+	a.URI = uri
+	return a, nil
+}
+
+// Authorize performs the initial step in the pre-authorization flow,
+// as opposed to order-based flow.
+// The caller will then need to choose from and perform a set of returned
+// challenges using c.Accept in order to successfully complete authorization.
+//
+// Once complete, the caller can use AuthorizeOrder which the CA
+// should provision with the already satisfied authorization.
+// For pre-RFC CAs, the caller can proceed directly to requesting a certificate
+// using CreateCert method.
+//
+// If an authorization has been previously granted, the CA may return
+// a valid authorization which has its Status field set to StatusValid.
+//
+// More about pre-authorization can be found at
+// https://tools.ietf.org/html/rfc8555#section-7.4.1.
+func (c *Client) Authorize(ctx context.Context, domain string) (*Authorization, error) {
+	return c.authorize(ctx, "dns", domain)
+}
+
+// AuthorizeIP is the same as Authorize but requests IP address authorization.
+// Clients which successfully obtain such authorization may request to issue
+// a certificate for IP addresses.
+//
+// See the ACME spec extension for more details about IP address identifiers:
+// https://tools.ietf.org/html/draft-ietf-acme-ip.
+func (c *Client) AuthorizeIP(ctx context.Context, ipaddr string) (*Authorization, error) {
+	return c.authorize(ctx, "ip", ipaddr)
+}
+
+func (c *Client) authorize(ctx context.Context, typ, val string) (*Authorization, error) {
+	if _, err := c.Discover(ctx); err != nil {
+		return nil, err
+	}
+
+	type authzID struct {
+		Type  string `json:"type"`
+		Value string `json:"value"`
+	}
+	req := struct {
+		Resource   string  `json:"resource"`
+		Identifier authzID `json:"identifier"`
+	}{
+		Resource:   "new-authz",
+		Identifier: authzID{Type: typ, Value: val},
+	}
+	res, err := c.post(ctx, nil, c.dir.AuthzURL, req, wantStatus(http.StatusCreated))
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	var v wireAuthz
+	if err := json.NewDecoder(res.Body).Decode(&v); err != nil {
+		return nil, fmt.Errorf("acme: invalid response: %v", err)
+	}
+	if v.Status != StatusPending && v.Status != StatusValid {
+		return nil, fmt.Errorf("acme: unexpected status: %s", v.Status)
+	}
+	return v.authorization(res.Header.Get("Location")), nil
+}
+
+// GetAuthorization retrieves an authorization identified by the given URL.
+//
+// If a caller needs to poll an authorization until its status is final,
+// see the WaitAuthorization method.
+func (c *Client) GetAuthorization(ctx context.Context, url string) (*Authorization, error) {
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	var res *http.Response
+	if dir.rfcCompliant() {
+		res, err = c.postAsGet(ctx, url, wantStatus(http.StatusOK))
+	} else {
+		res, err = c.get(ctx, url, wantStatus(http.StatusOK, http.StatusAccepted))
+	}
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+	var v wireAuthz
+	if err := json.NewDecoder(res.Body).Decode(&v); err != nil {
+		return nil, fmt.Errorf("acme: invalid response: %v", err)
+	}
+	return v.authorization(url), nil
+}
+
+// RevokeAuthorization relinquishes an existing authorization identified
+// by the given URL.
+// The url argument is an Authorization.URI value.
+//
+// If successful, the caller will be required to obtain a new authorization
+// using the Authorize or AuthorizeOrder methods before being able to request
+// a new certificate for the domain associated with the authorization.
+//
+// It does not revoke existing certificates.
+func (c *Client) RevokeAuthorization(ctx context.Context, url string) error {
+	// Required for c.accountKID() when in RFC mode.
+	if _, err := c.Discover(ctx); err != nil {
+		return err
+	}
+
+	req := struct {
+		Resource string `json:"resource"`
+		Status   string `json:"status"`
+		Delete   bool   `json:"delete"`
+	}{
+		Resource: "authz",
+		Status:   "deactivated",
+		Delete:   true,
+	}
+	res, err := c.post(ctx, nil, url, req, wantStatus(http.StatusOK))
+	if err != nil {
+		return err
+	}
+	defer res.Body.Close()
+	return nil
+}
+
+// WaitAuthorization polls an authorization at the given URL
+// until it is in one of the final states, StatusValid or StatusInvalid,
+// the ACME CA responded with a 4xx error code, or the context is done.
+//
+// It returns a non-nil Authorization only if its Status is StatusValid.
+// In all other cases WaitAuthorization returns an error.
+// If the Status is StatusInvalid, the returned error is of type *AuthorizationError.
+func (c *Client) WaitAuthorization(ctx context.Context, url string) (*Authorization, error) {
+	// Required for c.accountKID() when in RFC mode.
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+	getfn := c.postAsGet
+	if !dir.rfcCompliant() {
+		getfn = c.get
+	}
+
+	for {
+		res, err := getfn(ctx, url, wantStatus(http.StatusOK, http.StatusAccepted))
+		if err != nil {
+			return nil, err
+		}
+
+		var raw wireAuthz
+		err = json.NewDecoder(res.Body).Decode(&raw)
+		res.Body.Close()
+		switch {
+		case err != nil:
+			// Skip and retry.
+		case raw.Status == StatusValid:
+			return raw.authorization(url), nil
+		case raw.Status == StatusInvalid:
+			return nil, raw.error(url)
+		}
+
+		// Exponential backoff is implemented in c.get above.
+		// This is just to prevent continuously hitting the CA
+		// while waiting for a final authorization status.
+		d := retryAfter(res.Header.Get("Retry-After"))
+		if d == 0 {
+			// Given that the fastest challenges TLS-SNI and HTTP-01
+			// require a CA to make at least 1 network round trip
+			// and most likely persist a challenge state,
+			// this default delay seems reasonable.
+			d = time.Second
+		}
+		t := time.NewTimer(d)
+		select {
+		case <-ctx.Done():
+			t.Stop()
+			return nil, ctx.Err()
+		case <-t.C:
+			// Retry.
+		}
+	}
+}
+
+// GetChallenge retrieves the current status of an challenge.
+//
+// A client typically polls a challenge status using this method.
+func (c *Client) GetChallenge(ctx context.Context, url string) (*Challenge, error) {
+	// Required for c.accountKID() when in RFC mode.
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	getfn := c.postAsGet
+	if !dir.rfcCompliant() {
+		getfn = c.get
+	}
+	res, err := getfn(ctx, url, wantStatus(http.StatusOK, http.StatusAccepted))
+	if err != nil {
+		return nil, err
+	}
+
+	defer res.Body.Close()
+	v := wireChallenge{URI: url}
+	if err := json.NewDecoder(res.Body).Decode(&v); err != nil {
+		return nil, fmt.Errorf("acme: invalid response: %v", err)
+	}
+	return v.challenge(), nil
+}
+
+// Accept informs the server that the client accepts one of its challenges
+// previously obtained with c.Authorize.
+//
+// The server will then perform the validation asynchronously.
+func (c *Client) Accept(ctx context.Context, chal *Challenge) (*Challenge, error) {
+	// Required for c.accountKID() when in RFC mode.
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	var req interface{} = json.RawMessage("{}") // RFC-compliant CA
+	if !dir.rfcCompliant() {
+		auth, err := keyAuth(c.Key.Public(), chal.Token)
+		if err != nil {
+			return nil, err
+		}
+		req = struct {
+			Resource string `json:"resource"`
+			Type     string `json:"type"`
+			Auth     string `json:"keyAuthorization"`
+		}{
+			Resource: "challenge",
+			Type:     chal.Type,
+			Auth:     auth,
+		}
+	}
+	res, err := c.post(ctx, nil, chal.URI, req, wantStatus(
+		http.StatusOK,       // according to the spec
+		http.StatusAccepted, // Let's Encrypt: see https://goo.gl/WsJ7VT (acme-divergences.md)
+	))
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	var v wireChallenge
+	if err := json.NewDecoder(res.Body).Decode(&v); err != nil {
+		return nil, fmt.Errorf("acme: invalid response: %v", err)
+	}
+	return v.challenge(), nil
+}
+
+// DNS01ChallengeRecord returns a DNS record value for a dns-01 challenge response.
+// A TXT record containing the returned value must be provisioned under
+// "_acme-challenge" name of the domain being validated.
+//
+// The token argument is a Challenge.Token value.
+func (c *Client) DNS01ChallengeRecord(token string) (string, error) {
+	ka, err := keyAuth(c.Key.Public(), token)
+	if err != nil {
+		return "", err
+	}
+	b := sha256.Sum256([]byte(ka))
+	return base64.RawURLEncoding.EncodeToString(b[:]), nil
+}
+
+// HTTP01ChallengeResponse returns the response for an http-01 challenge.
+// Servers should respond with the value to HTTP requests at the URL path
+// provided by HTTP01ChallengePath to validate the challenge and prove control
+// over a domain name.
+//
+// The token argument is a Challenge.Token value.
+func (c *Client) HTTP01ChallengeResponse(token string) (string, error) {
+	return keyAuth(c.Key.Public(), token)
+}
+
+// HTTP01ChallengePath returns the URL path at which the response for an http-01 challenge
+// should be provided by the servers.
+// The response value can be obtained with HTTP01ChallengeResponse.
+//
+// The token argument is a Challenge.Token value.
+func (c *Client) HTTP01ChallengePath(token string) string {
+	return "/.well-known/acme-challenge/" + token
+}
+
+// TLSSNI01ChallengeCert creates a certificate for TLS-SNI-01 challenge response.
+//
+// Deprecated: This challenge type is unused in both draft-02 and RFC versions of ACME spec.
+func (c *Client) TLSSNI01ChallengeCert(token string, opt ...CertOption) (cert tls.Certificate, name string, err error) {
+	ka, err := keyAuth(c.Key.Public(), token)
+	if err != nil {
+		return tls.Certificate{}, "", err
+	}
+	b := sha256.Sum256([]byte(ka))
+	h := hex.EncodeToString(b[:])
+	name = fmt.Sprintf("%s.%s.acme.invalid", h[:32], h[32:])
+	cert, err = tlsChallengeCert([]string{name}, opt)
+	if err != nil {
+		return tls.Certificate{}, "", err
+	}
+	return cert, name, nil
+}
+
+// TLSSNI02ChallengeCert creates a certificate for TLS-SNI-02 challenge response.
+//
+// Deprecated: This challenge type is unused in both draft-02 and RFC versions of ACME spec.
+func (c *Client) TLSSNI02ChallengeCert(token string, opt ...CertOption) (cert tls.Certificate, name string, err error) {
+	b := sha256.Sum256([]byte(token))
+	h := hex.EncodeToString(b[:])
+	sanA := fmt.Sprintf("%s.%s.token.acme.invalid", h[:32], h[32:])
+
+	ka, err := keyAuth(c.Key.Public(), token)
+	if err != nil {
+		return tls.Certificate{}, "", err
+	}
+	b = sha256.Sum256([]byte(ka))
+	h = hex.EncodeToString(b[:])
+	sanB := fmt.Sprintf("%s.%s.ka.acme.invalid", h[:32], h[32:])
+
+	cert, err = tlsChallengeCert([]string{sanA, sanB}, opt)
+	if err != nil {
+		return tls.Certificate{}, "", err
+	}
+	return cert, sanA, nil
+}
+
+// TLSALPN01ChallengeCert creates a certificate for TLS-ALPN-01 challenge response.
+// Servers can present the certificate to validate the challenge and prove control
+// over a domain name. For more details on TLS-ALPN-01 see
+// https://tools.ietf.org/html/draft-shoemaker-acme-tls-alpn-00#section-3
+//
+// The token argument is a Challenge.Token value.
+// If a WithKey option is provided, its private part signs the returned cert,
+// and the public part is used to specify the signee.
+// If no WithKey option is provided, a new ECDSA key is generated using P-256 curve.
+//
+// The returned certificate is valid for the next 24 hours and must be presented only when
+// the server name in the TLS ClientHello matches the domain, and the special acme-tls/1 ALPN protocol
+// has been specified.
+func (c *Client) TLSALPN01ChallengeCert(token, domain string, opt ...CertOption) (cert tls.Certificate, err error) {
+	ka, err := keyAuth(c.Key.Public(), token)
+	if err != nil {
+		return tls.Certificate{}, err
+	}
+	shasum := sha256.Sum256([]byte(ka))
+	extValue, err := asn1.Marshal(shasum[:])
+	if err != nil {
+		return tls.Certificate{}, err
+	}
+	acmeExtension := pkix.Extension{
+		Id:       idPeACMEIdentifier,
+		Critical: true,
+		Value:    extValue,
+	}
+
+	tmpl := defaultTLSChallengeCertTemplate()
+
+	var newOpt []CertOption
+	for _, o := range opt {
+		switch o := o.(type) {
+		case *certOptTemplate:
+			t := *(*x509.Certificate)(o) // shallow copy is ok
+			tmpl = &t
+		default:
+			newOpt = append(newOpt, o)
+		}
+	}
+	tmpl.ExtraExtensions = append(tmpl.ExtraExtensions, acmeExtension)
+	newOpt = append(newOpt, WithTemplate(tmpl))
+	return tlsChallengeCert([]string{domain}, newOpt)
+}
+
+// doReg sends all types of registration requests the old way (pre-RFC world).
+// The type of request is identified by typ argument, which is a "resource"
+// in the ACME spec terms.
+//
+// A non-nil acct argument indicates whether the intention is to mutate data
+// of the Account. Only Contact and Agreement of its fields are used
+// in such cases.
+func (c *Client) doReg(ctx context.Context, url string, typ string, acct *Account) (*Account, error) {
+	req := struct {
+		Resource  string   `json:"resource"`
+		Contact   []string `json:"contact,omitempty"`
+		Agreement string   `json:"agreement,omitempty"`
+	}{
+		Resource: typ,
+	}
+	if acct != nil {
+		req.Contact = acct.Contact
+		req.Agreement = acct.AgreedTerms
+	}
+	res, err := c.post(ctx, nil, url, req, wantStatus(
+		http.StatusOK,       // updates and deletes
+		http.StatusCreated,  // new account creation
+		http.StatusAccepted, // Let's Encrypt divergent implementation
+	))
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	var v struct {
+		Contact        []string
+		Agreement      string
+		Authorizations string
+		Certificates   string
+	}
+	if err := json.NewDecoder(res.Body).Decode(&v); err != nil {
+		return nil, fmt.Errorf("acme: invalid response: %v", err)
+	}
+	var tos string
+	if v := linkHeader(res.Header, "terms-of-service"); len(v) > 0 {
+		tos = v[0]
+	}
+	var authz string
+	if v := linkHeader(res.Header, "next"); len(v) > 0 {
+		authz = v[0]
+	}
+	return &Account{
+		URI:            res.Header.Get("Location"),
+		Contact:        v.Contact,
+		AgreedTerms:    v.Agreement,
+		CurrentTerms:   tos,
+		Authz:          authz,
+		Authorizations: v.Authorizations,
+		Certificates:   v.Certificates,
+	}, nil
+}
+
+// popNonce returns a nonce value previously stored with c.addNonce
+// or fetches a fresh one from c.dir.NonceURL.
+// If NonceURL is empty, it first tries c.directoryURL() and, failing that,
+// the provided url.
+func (c *Client) popNonce(ctx context.Context, url string) (string, error) {
+	c.noncesMu.Lock()
+	defer c.noncesMu.Unlock()
+	if len(c.nonces) == 0 {
+		if c.dir != nil && c.dir.NonceURL != "" {
+			return c.fetchNonce(ctx, c.dir.NonceURL)
+		}
+		dirURL := c.directoryURL()
+		v, err := c.fetchNonce(ctx, dirURL)
+		if err != nil && url != dirURL {
+			v, err = c.fetchNonce(ctx, url)
+		}
+		return v, err
+	}
+	var nonce string
+	for nonce = range c.nonces {
+		delete(c.nonces, nonce)
+		break
+	}
+	return nonce, nil
+}
+
+// clearNonces clears any stored nonces
+func (c *Client) clearNonces() {
+	c.noncesMu.Lock()
+	defer c.noncesMu.Unlock()
+	c.nonces = make(map[string]struct{})
+}
+
+// addNonce stores a nonce value found in h (if any) for future use.
+func (c *Client) addNonce(h http.Header) {
+	v := nonceFromHeader(h)
+	if v == "" {
+		return
+	}
+	c.noncesMu.Lock()
+	defer c.noncesMu.Unlock()
+	if len(c.nonces) >= maxNonces {
+		return
+	}
+	if c.nonces == nil {
+		c.nonces = make(map[string]struct{})
+	}
+	c.nonces[v] = struct{}{}
+}
+
+func (c *Client) fetchNonce(ctx context.Context, url string) (string, error) {
+	r, err := http.NewRequest("HEAD", url, nil)
+	if err != nil {
+		return "", err
+	}
+	resp, err := c.doNoRetry(ctx, r)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+	nonce := nonceFromHeader(resp.Header)
+	if nonce == "" {
+		if resp.StatusCode > 299 {
+			return "", responseError(resp)
+		}
+		return "", errors.New("acme: nonce not found")
+	}
+	return nonce, nil
+}
+
+func nonceFromHeader(h http.Header) string {
+	return h.Get("Replay-Nonce")
+}
+
+func (c *Client) responseCert(ctx context.Context, res *http.Response, bundle bool) ([][]byte, error) {
+	b, err := ioutil.ReadAll(io.LimitReader(res.Body, maxCertSize+1))
+	if err != nil {
+		return nil, fmt.Errorf("acme: response stream: %v", err)
+	}
+	if len(b) > maxCertSize {
+		return nil, errors.New("acme: certificate is too big")
+	}
+	cert := [][]byte{b}
+	if !bundle {
+		return cert, nil
+	}
+
+	// Append CA chain cert(s).
+	// At least one is required according to the spec:
+	// https://tools.ietf.org/html/draft-ietf-acme-acme-03#section-6.3.1
+	up := linkHeader(res.Header, "up")
+	if len(up) == 0 {
+		return nil, errors.New("acme: rel=up link not found")
+	}
+	if len(up) > maxChainLen {
+		return nil, errors.New("acme: rel=up link is too large")
+	}
+	for _, url := range up {
+		cc, err := c.chainCert(ctx, url, 0)
+		if err != nil {
+			return nil, err
+		}
+		cert = append(cert, cc...)
+	}
+	return cert, nil
+}
+
+// chainCert fetches CA certificate chain recursively by following "up" links.
+// Each recursive call increments the depth by 1, resulting in an error
+// if the recursion level reaches maxChainLen.
+//
+// First chainCert call starts with depth of 0.
+func (c *Client) chainCert(ctx context.Context, url string, depth int) ([][]byte, error) {
+	if depth >= maxChainLen {
+		return nil, errors.New("acme: certificate chain is too deep")
+	}
+
+	res, err := c.get(ctx, url, wantStatus(http.StatusOK))
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+	b, err := ioutil.ReadAll(io.LimitReader(res.Body, maxCertSize+1))
+	if err != nil {
+		return nil, err
+	}
+	if len(b) > maxCertSize {
+		return nil, errors.New("acme: certificate is too big")
+	}
+	chain := [][]byte{b}
+
+	uplink := linkHeader(res.Header, "up")
+	if len(uplink) > maxChainLen {
+		return nil, errors.New("acme: certificate chain is too large")
+	}
+	for _, up := range uplink {
+		cc, err := c.chainCert(ctx, up, depth+1)
+		if err != nil {
+			return nil, err
+		}
+		chain = append(chain, cc...)
+	}
+
+	return chain, nil
+}
+
+// linkHeader returns URI-Reference values of all Link headers
+// with relation-type rel.
+// See https://tools.ietf.org/html/rfc5988#section-5 for details.
+func linkHeader(h http.Header, rel string) []string {
+	var links []string
+	for _, v := range h["Link"] {
+		parts := strings.Split(v, ";")
+		for _, p := range parts {
+			p = strings.TrimSpace(p)
+			if !strings.HasPrefix(p, "rel=") {
+				continue
+			}
+			if v := strings.Trim(p[4:], `"`); v == rel {
+				links = append(links, strings.Trim(parts[0], "<>"))
+			}
+		}
+	}
+	return links
+}
+
+// keyAuth generates a key authorization string for a given token.
+func keyAuth(pub crypto.PublicKey, token string) (string, error) {
+	th, err := JWKThumbprint(pub)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("%s.%s", token, th), nil
+}
+
+// defaultTLSChallengeCertTemplate is a template used to create challenge certs for TLS challenges.
+func defaultTLSChallengeCertTemplate() *x509.Certificate {
+	return &x509.Certificate{
+		SerialNumber:          big.NewInt(1),
+		NotBefore:             time.Now(),
+		NotAfter:              time.Now().Add(24 * time.Hour),
+		BasicConstraintsValid: true,
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+	}
+}
+
+// tlsChallengeCert creates a temporary certificate for TLS-SNI challenges
+// with the given SANs and auto-generated public/private key pair.
+// The Subject Common Name is set to the first SAN to aid debugging.
+// To create a cert with a custom key pair, specify WithKey option.
+func tlsChallengeCert(san []string, opt []CertOption) (tls.Certificate, error) {
+	var key crypto.Signer
+	tmpl := defaultTLSChallengeCertTemplate()
+	for _, o := range opt {
+		switch o := o.(type) {
+		case *certOptKey:
+			if key != nil {
+				return tls.Certificate{}, errors.New("acme: duplicate key option")
+			}
+			key = o.key
+		case *certOptTemplate:
+			t := *(*x509.Certificate)(o) // shallow copy is ok
+			tmpl = &t
+		default:
+			// package's fault, if we let this happen:
+			panic(fmt.Sprintf("unsupported option type %T", o))
+		}
+	}
+	if key == nil {
+		var err error
+		if key, err = ecdsa.GenerateKey(elliptic.P256(), rand.Reader); err != nil {
+			return tls.Certificate{}, err
+		}
+	}
+	tmpl.DNSNames = san
+	if len(san) > 0 {
+		tmpl.Subject.CommonName = san[0]
+	}
+
+	der, err := x509.CreateCertificate(rand.Reader, tmpl, tmpl, key.Public(), key)
+	if err != nil {
+		return tls.Certificate{}, err
+	}
+	return tls.Certificate{
+		Certificate: [][]byte{der},
+		PrivateKey:  key,
+	}, nil
+}
+
+// encodePEM returns b encoded as PEM with block of type typ.
+func encodePEM(typ string, b []byte) []byte {
+	pb := &pem.Block{Type: typ, Bytes: b}
+	return pem.EncodeToMemory(pb)
+}
+
+// timeNow is useful for testing for fixed current time.
+var timeNow = time.Now

vendor/golang.org/x/crypto/acme/autocert/autocert.go

@@ -0,0 +1,1249 @@
+// 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"
+	"golang.org/x/net/idna"
+)
+
+// DefaultACMEDirectory is the default ACME Directory URL used when the Manager's Client is nil.
+const DefaultACMEDirectory = "https://acme-v02.api.letsencrypt.org/directory"
+
+// 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.
+//
+// Note that all hosts will be converted to Punycode via idna.Lookup.ToASCII so that
+// Manager.GetCertificate can handle the Unicode IDN and mixedcase hosts correctly.
+// Invalid hosts will be silently ignored.
+func HostWhitelist(hosts ...string) HostPolicy {
+	whitelist := make(map[string]bool, len(hosts))
+	for _, h := range hosts {
+		if h, err := idna.Lookup.ToASCII(h); err == nil {
+			whitelist[h] = true
+		}
+	}
+	return func(_ context.Context, host string) error {
+		if !whitelist[host] {
+			return fmt.Errorf("acme/autocert: host %q not configured in HostWhitelist", host)
+		}
+		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"
+// or "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 DefaultACMEDirectory
+	// as the 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
+
+	// challengeMu guards tryHTTP01, certTokens and httpTokens.
+	challengeMu 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-alpn-01 challenges
+	// and is keyed by the domain name which matches the ClientHello server name.
+	// 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 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.
+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")
+	}
+
+	// Note that this conversion is necessary because some server names in the handshakes
+	// started by some clients (such as cURL) are not converted to Punycode, which will
+	// prevent us from obtaining certificates for them. In addition, we should also treat
+	// example.com and EXAMPLE.COM as equivalent and return the same certificate for them.
+	// Fortunately, this conversion also helped us deal with this kind of mixedcase problems.
+	//
+	// Due to the "σςΣ" problem (see https://unicode.org/faq/idn.html#22), we can't use
+	// idna.Punycode.ToASCII (or just idna.ToASCII) here.
+	name, err := idna.Lookup.ToASCII(name)
+	if err != nil {
+		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-ALPN challenge.
+	if wantsTokenCert(hello) {
+		m.challengeMu.RLock()
+		defer m.challengeMu.RUnlock()
+		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
+	}
+	return false
+}
+
+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.challengeMu.Lock()
+	defer m.challengeMu.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) {
+	csr, err := certRequest(key, ck.domain, m.ExtraExtensions)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	client, err := m.acmeClient(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+	dir, err := client.Discover(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	var chain [][]byte
+	switch {
+	// Pre-RFC legacy CA.
+	case dir.OrderURL == "":
+		if err := m.verify(ctx, client, ck.domain); err != nil {
+			return nil, nil, err
+		}
+		der, _, err := client.CreateCert(ctx, csr, 0, true)
+		if err != nil {
+			return nil, nil, err
+		}
+		chain = der
+	// RFC 8555 compliant CA.
+	default:
+		o, err := m.verifyRFC(ctx, client, ck.domain)
+		if err != nil {
+			return nil, nil, err
+		}
+		der, _, err := client.CreateOrderCert(ctx, o.FinalizeURL, csr, true)
+		if err != nil {
+			return nil, nil, err
+		}
+		chain = der
+	}
+	leaf, err = validCert(ck, chain, key, m.now())
+	if err != nil {
+		return nil, nil, err
+	}
+	return chain, leaf, nil
+}
+
+// verify runs the identifier (domain) pre-authorization flow for legacy CAs
+// using each applicable ACME challenge type.
+func (m *Manager) verify(ctx context.Context, client *acme.Client, domain string) error {
+	// Remove all hanging authorizations to reduce rate limit quotas
+	// after we're done.
+	var authzURLs []string
+	defer func() {
+		go m.deactivatePendingAuthz(authzURLs)
+	}()
+
+	// errs accumulates challenge failure errors, printed if all fail
+	errs := make(map[*acme.Challenge]error)
+	challengeTypes := m.supportedChallengeTypes()
+	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
+		}
+		authzURLs = append(authzURLs, authz.URI)
+		// 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)
+		}
+
+		// 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
+		}
+		return nil
+	}
+}
+
+// verifyRFC runs the identifier (domain) order-based authorization flow for RFC compliant CAs
+// using each applicable ACME challenge type.
+func (m *Manager) verifyRFC(ctx context.Context, client *acme.Client, domain string) (*acme.Order, error) {
+	// Try each supported challenge type starting with a new order each time.
+	// The nextTyp index of the next challenge type to try is shared across
+	// all order authorizations: if we've tried a challenge type once and it didn't work,
+	// it will most likely not work on another order's authorization either.
+	challengeTypes := m.supportedChallengeTypes()
+	nextTyp := 0 // challengeTypes index
+AuthorizeOrderLoop:
+	for {
+		o, err := client.AuthorizeOrder(ctx, acme.DomainIDs(domain))
+		if err != nil {
+			return nil, err
+		}
+		// Remove all hanging authorizations to reduce rate limit quotas
+		// after we're done.
+		defer func(urls []string) {
+			go m.deactivatePendingAuthz(urls)
+		}(o.AuthzURLs)
+
+		// Check if there's actually anything we need to do.
+		switch o.Status {
+		case acme.StatusReady:
+			// Already authorized.
+			return o, nil
+		case acme.StatusPending:
+			// Continue normal Order-based flow.
+		default:
+			return nil, fmt.Errorf("acme/autocert: invalid new order status %q; order URL: %q", o.Status, o.URI)
+		}
+
+		// Satisfy all pending authorizations.
+		for _, zurl := range o.AuthzURLs {
+			z, err := client.GetAuthorization(ctx, zurl)
+			if err != nil {
+				return nil, err
+			}
+			if z.Status != acme.StatusPending {
+				// We are interested only in pending authorizations.
+				continue
+			}
+			// Pick the next preferred challenge.
+			var chal *acme.Challenge
+			for chal == nil && nextTyp < len(challengeTypes) {
+				chal = pickChallenge(challengeTypes[nextTyp], z.Challenges)
+				nextTyp++
+			}
+			if chal == nil {
+				return nil, fmt.Errorf("acme/autocert: unable to satisfy %q for domain %q: no viable challenge type found", z.URI, domain)
+			}
+			// Respond to the challenge and wait for validation result.
+			cleanup, err := m.fulfill(ctx, client, chal, domain)
+			if err != nil {
+				continue AuthorizeOrderLoop
+			}
+			defer cleanup()
+			if _, err := client.Accept(ctx, chal); err != nil {
+				continue AuthorizeOrderLoop
+			}
+			if _, err := client.WaitAuthorization(ctx, z.URI); err != nil {
+				continue AuthorizeOrderLoop
+			}
+		}
+
+		// All authorizations are satisfied.
+		// Wait for the CA to update the order status.
+		o, err = client.WaitOrder(ctx, o.URI)
+		if err != nil {
+			continue AuthorizeOrderLoop
+		}
+		return o, nil
+	}
+}
+
+func pickChallenge(typ string, chal []*acme.Challenge) *acme.Challenge {
+	for _, c := range chal {
+		if c.Type == typ {
+			return c
+		}
+	}
+	return nil
+}
+
+func (m *Manager) supportedChallengeTypes() []string {
+	m.challengeMu.RLock()
+	defer m.challengeMu.RUnlock()
+	typ := []string{"tls-alpn-01"}
+	if m.tryHTTP01 {
+		typ = append(typ, "http-01")
+	}
+	return typ
+}
+
+// deactivatePendingAuthz relinquishes all authorizations identified by the elements
+// of the provided uri slice which are in "pending" state.
+// It ignores revocation errors.
+//
+// deactivatePendingAuthz takes no context argument and instead runs with its own
+// "detached" context because deactivations are done in a goroutine separate from
+// that of the main issuance or renewal flow.
+func (m *Manager) deactivatePendingAuthz(uri []string) {
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
+	defer cancel()
+	client, err := m.acmeClient(ctx)
+	if err != nil {
+		return
+	}
+	for _, u := range uri {
+		z, err := client.GetAuthorization(ctx, u)
+		if err == nil && z.Status == acme.StatusPending {
+			client.RevokeAuthorization(ctx, u)
+		}
+	}
+}
+
+// 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 "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)
+}
+
+// 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.challengeMu.Lock()
+	defer m.challengeMu.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.challengeMu.Lock()
+	defer m.challengeMu.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.challengeMu.RLock()
+	defer m.challengeMu.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.challengeMu.Lock()
+	defer m.challengeMu.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.challengeMu.Lock()
+	defer m.challengeMu.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: DefaultACMEDirectory}
+	}
+	if client.Key == nil {
+		var err error
+		client.Key, err = m.accountKey(ctx)
+		if err != nil {
+			return nil, err
+		}
+	}
+	if client.UserAgent == "" {
+		client.UserAgent = "autocert"
+	}
+	var contact []string
+	if m.Email != "" {
+		contact = []string{"mailto:" + m.Email}
+	}
+	a := &acme.Account{Contact: contact}
+	_, err := client.Register(ctx, a, m.Prompt)
+	if err == nil || isAccountAlreadyExist(err) {
+		m.client = client
+		err = nil
+	}
+	return m.client, err
+}
+
+// isAccountAlreadyExist reports whether the err, as returned from acme.Client.Register,
+// indicates the account has already been registered.
+func isAccountAlreadyExist(err error) bool {
+	if err == acme.ErrAccountAlreadyExists {
+		return true
+	}
+	ae, ok := err.(*acme.Error)
+	return ok && ae.StatusCode == http.StatusConflict
+}
+
+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) {}
+)

vendor/golang.org/x/crypto/acme/autocert/cache.go

@@ -0,0 +1,136 @@
+// 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
+		}
+		defer os.Remove(tmp)
+		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) (name string, reterr error) {
+	// TempFile uses 0600 permissions
+	f, err := ioutil.TempFile(string(d), prefix)
+	if err != nil {
+		return "", err
+	}
+	defer func() {
+		if reterr != nil {
+			os.Remove(f.Name())
+		}
+	}()
+	if _, err := f.Write(b); err != nil {
+		f.Close()
+		return "", err
+	}
+	return f.Name(), f.Close()
+}

vendor/golang.org/x/crypto/acme/autocert/listener.go

@@ -0,0 +1,155 @@
+// 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{
+		conf: m.TLSConfig(),
+	}
+	ln.tcpListener, ln.tcpListenErr = net.Listen("tcp", ":443")
+	return ln
+}
+
+type listener struct {
+	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)
+}

vendor/golang.org/x/crypto/acme/autocert/renewal.go

@@ -0,0 +1,141 @@
+// 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) {}

vendor/golang.org/x/crypto/acme/http.go

@@ -0,0 +1,321 @@
+// Copyright 2018 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 acme
+
+import (
+	"bytes"
+	"context"
+	"crypto"
+	"crypto/rand"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"math/big"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// retryTimer encapsulates common logic for retrying unsuccessful requests.
+// It is not safe for concurrent use.
+type retryTimer struct {
+	// backoffFn provides backoff delay sequence for retries.
+	// See Client.RetryBackoff doc comment.
+	backoffFn func(n int, r *http.Request, res *http.Response) time.Duration
+	// n is the current retry attempt.
+	n int
+}
+
+func (t *retryTimer) inc() {
+	t.n++
+}
+
+// backoff pauses the current goroutine as described in Client.RetryBackoff.
+func (t *retryTimer) backoff(ctx context.Context, r *http.Request, res *http.Response) error {
+	d := t.backoffFn(t.n, r, res)
+	if d <= 0 {
+		return fmt.Errorf("acme: no more retries for %s; tried %d time(s)", r.URL, t.n)
+	}
+	wakeup := time.NewTimer(d)
+	defer wakeup.Stop()
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-wakeup.C:
+		return nil
+	}
+}
+
+func (c *Client) retryTimer() *retryTimer {
+	f := c.RetryBackoff
+	if f == nil {
+		f = defaultBackoff
+	}
+	return &retryTimer{backoffFn: f}
+}
+
+// defaultBackoff provides default Client.RetryBackoff implementation
+// using a truncated exponential backoff algorithm,
+// as described in Client.RetryBackoff.
+//
+// The n argument is always bounded between 1 and 30.
+// The returned value is always greater than 0.
+func defaultBackoff(n int, r *http.Request, res *http.Response) time.Duration {
+	const max = 10 * time.Second
+	var jitter time.Duration
+	if x, err := rand.Int(rand.Reader, big.NewInt(1000)); err == nil {
+		// Set the minimum to 1ms to avoid a case where
+		// an invalid Retry-After value is parsed into 0 below,
+		// resulting in the 0 returned value which would unintentionally
+		// stop the retries.
+		jitter = (1 + time.Duration(x.Int64())) * time.Millisecond
+	}
+	if v, ok := res.Header["Retry-After"]; ok {
+		return retryAfter(v[0]) + jitter
+	}
+
+	if n < 1 {
+		n = 1
+	}
+	if n > 30 {
+		n = 30
+	}
+	d := time.Duration(1<<uint(n-1))*time.Second + jitter
+	if d > max {
+		return max
+	}
+	return d
+}
+
+// retryAfter parses a Retry-After HTTP header value,
+// trying to convert v into an int (seconds) or use http.ParseTime otherwise.
+// It returns zero value if v cannot be parsed.
+func retryAfter(v string) time.Duration {
+	if i, err := strconv.Atoi(v); err == nil {
+		return time.Duration(i) * time.Second
+	}
+	t, err := http.ParseTime(v)
+	if err != nil {
+		return 0
+	}
+	return t.Sub(timeNow())
+}
+
+// resOkay is a function that reports whether the provided response is okay.
+// It is expected to keep the response body unread.
+type resOkay func(*http.Response) bool
+
+// wantStatus returns a function which reports whether the code
+// matches the status code of a response.
+func wantStatus(codes ...int) resOkay {
+	return func(res *http.Response) bool {
+		for _, code := range codes {
+			if code == res.StatusCode {
+				return true
+			}
+		}
+		return false
+	}
+}
+
+// get issues an unsigned GET request to the specified URL.
+// It returns a non-error value only when ok reports true.
+//
+// get retries unsuccessful attempts according to c.RetryBackoff
+// until the context is done or a non-retriable error is received.
+func (c *Client) get(ctx context.Context, url string, ok resOkay) (*http.Response, error) {
+	retry := c.retryTimer()
+	for {
+		req, err := http.NewRequest("GET", url, nil)
+		if err != nil {
+			return nil, err
+		}
+		res, err := c.doNoRetry(ctx, req)
+		switch {
+		case err != nil:
+			return nil, err
+		case ok(res):
+			return res, nil
+		case isRetriable(res.StatusCode):
+			retry.inc()
+			resErr := responseError(res)
+			res.Body.Close()
+			// Ignore the error value from retry.backoff
+			// and return the one from last retry, as received from the CA.
+			if retry.backoff(ctx, req, res) != nil {
+				return nil, resErr
+			}
+		default:
+			defer res.Body.Close()
+			return nil, responseError(res)
+		}
+	}
+}
+
+// postAsGet is POST-as-GET, a replacement for GET in RFC8555
+// as described in https://tools.ietf.org/html/rfc8555#section-6.3.
+// It makes a POST request in KID form with zero JWS payload.
+// See nopayload doc comments in jws.go.
+func (c *Client) postAsGet(ctx context.Context, url string, ok resOkay) (*http.Response, error) {
+	return c.post(ctx, nil, url, noPayload, ok)
+}
+
+// post issues a signed POST request in JWS format using the provided key
+// to the specified URL. If key is nil, c.Key is used instead.
+// It returns a non-error value only when ok reports true.
+//
+// post retries unsuccessful attempts according to c.RetryBackoff
+// until the context is done or a non-retriable error is received.
+// It uses postNoRetry to make individual requests.
+func (c *Client) post(ctx context.Context, key crypto.Signer, url string, body interface{}, ok resOkay) (*http.Response, error) {
+	retry := c.retryTimer()
+	for {
+		res, req, err := c.postNoRetry(ctx, key, url, body)
+		if err != nil {
+			return nil, err
+		}
+		if ok(res) {
+			return res, nil
+		}
+		resErr := responseError(res)
+		res.Body.Close()
+		switch {
+		// Check for bad nonce before isRetriable because it may have been returned
+		// with an unretriable response code such as 400 Bad Request.
+		case isBadNonce(resErr):
+			// Consider any previously stored nonce values to be invalid.
+			c.clearNonces()
+		case !isRetriable(res.StatusCode):
+			return nil, resErr
+		}
+		retry.inc()
+		// Ignore the error value from retry.backoff
+		// and return the one from last retry, as received from the CA.
+		if err := retry.backoff(ctx, req, res); err != nil {
+			return nil, resErr
+		}
+	}
+}
+
+// postNoRetry signs the body with the given key and POSTs it to the provided url.
+// It is used by c.post to retry unsuccessful attempts.
+// The body argument must be JSON-serializable.
+//
+// If key argument is nil, c.Key is used to sign the request.
+// If key argument is nil and c.accountKID returns a non-zero keyID,
+// the request is sent in KID form. Otherwise, JWK form is used.
+//
+// In practice, when interfacing with RFC-compliant CAs most requests are sent in KID form
+// and JWK is used only when KID is unavailable: new account endpoint and certificate
+// revocation requests authenticated by a cert key.
+// See jwsEncodeJSON for other details.
+func (c *Client) postNoRetry(ctx context.Context, key crypto.Signer, url string, body interface{}) (*http.Response, *http.Request, error) {
+	kid := noKeyID
+	if key == nil {
+		key = c.Key
+		kid = c.accountKID(ctx)
+	}
+	nonce, err := c.popNonce(ctx, url)
+	if err != nil {
+		return nil, nil, err
+	}
+	b, err := jwsEncodeJSON(body, key, kid, nonce, url)
+	if err != nil {
+		return nil, nil, err
+	}
+	req, err := http.NewRequest("POST", url, bytes.NewReader(b))
+	if err != nil {
+		return nil, nil, err
+	}
+	req.Header.Set("Content-Type", "application/jose+json")
+	res, err := c.doNoRetry(ctx, req)
+	if err != nil {
+		return nil, nil, err
+	}
+	c.addNonce(res.Header)
+	return res, req, nil
+}
+
+// doNoRetry issues a request req, replacing its context (if any) with ctx.
+func (c *Client) doNoRetry(ctx context.Context, req *http.Request) (*http.Response, error) {
+	req.Header.Set("User-Agent", c.userAgent())
+	res, err := c.httpClient().Do(req.WithContext(ctx))
+	if err != nil {
+		select {
+		case <-ctx.Done():
+			// Prefer the unadorned context error.
+			// (The acme package had tests assuming this, previously from ctxhttp's
+			// behavior, predating net/http supporting contexts natively)
+			// TODO(bradfitz): reconsider this in the future. But for now this
+			// requires no test updates.
+			return nil, ctx.Err()
+		default:
+			return nil, err
+		}
+	}
+	return res, nil
+}
+
+func (c *Client) httpClient() *http.Client {
+	if c.HTTPClient != nil {
+		return c.HTTPClient
+	}
+	return http.DefaultClient
+}
+
+// packageVersion is the version of the module that contains this package, for
+// sending as part of the User-Agent header. It's set in version_go112.go.
+var packageVersion string
+
+// userAgent returns the User-Agent header value. It includes the package name,
+// the module version (if available), and the c.UserAgent value (if set).
+func (c *Client) userAgent() string {
+	ua := "golang.org/x/crypto/acme"
+	if packageVersion != "" {
+		ua += "@" + packageVersion
+	}
+	if c.UserAgent != "" {
+		ua = c.UserAgent + " " + ua
+	}
+	return ua
+}
+
+// isBadNonce reports whether err is an ACME "badnonce" error.
+func isBadNonce(err error) bool {
+	// According to the spec badNonce is urn:ietf:params:acme:error:badNonce.
+	// However, ACME servers in the wild return their versions of the error.
+	// See https://tools.ietf.org/html/draft-ietf-acme-acme-02#section-5.4
+	// and https://github.com/letsencrypt/boulder/blob/0e07eacb/docs/acme-divergences.md#section-66.
+	ae, ok := err.(*Error)
+	return ok && strings.HasSuffix(strings.ToLower(ae.ProblemType), ":badnonce")
+}
+
+// isRetriable reports whether a request can be retried
+// based on the response status code.
+//
+// Note that a "bad nonce" error is returned with a non-retriable 400 Bad Request code.
+// Callers should parse the response and check with isBadNonce.
+func isRetriable(code int) bool {
+	return code <= 399 || code >= 500 || code == http.StatusTooManyRequests
+}
+
+// responseError creates an error of Error type from resp.
+func responseError(resp *http.Response) error {
+	// don't care if ReadAll returns an error:
+	// json.Unmarshal will fail in that case anyway
+	b, _ := ioutil.ReadAll(resp.Body)
+	e := &wireError{Status: resp.StatusCode}
+	if err := json.Unmarshal(b, e); err != nil {
+		// this is not a regular error response:
+		// populate detail with anything we received,
+		// e.Status will already contain HTTP response code value
+		e.Detail = string(b)
+		if e.Detail == "" {
+			e.Detail = resp.Status
+		}
+	}
+	return e.error(resp.Header)
+}

vendor/golang.org/x/crypto/acme/jws.go

@@ -0,0 +1,229 @@
+// Copyright 2015 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 acme
+
+import (
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/hmac"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/sha256"
+	_ "crypto/sha512" // need for EC keys
+	"encoding/asn1"
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"math/big"
+)
+
+// keyID is the account identity provided by a CA during registration.
+type keyID string
+
+// noKeyID indicates that jwsEncodeJSON should compute and use JWK instead of a KID.
+// See jwsEncodeJSON for details.
+const noKeyID = keyID("")
+
+// noPayload indicates jwsEncodeJSON will encode zero-length octet string
+// in a JWS request. This is called POST-as-GET in RFC 8555 and is used to make
+// authenticated GET requests via POSTing with an empty payload.
+// See https://tools.ietf.org/html/rfc8555#section-6.3 for more details.
+const noPayload = ""
+
+// jsonWebSignature can be easily serialized into a JWS following
+// https://tools.ietf.org/html/rfc7515#section-3.2.
+type jsonWebSignature struct {
+	Protected string `json:"protected"`
+	Payload   string `json:"payload"`
+	Sig       string `json:"signature"`
+}
+
+// jwsEncodeJSON signs claimset using provided key and a nonce.
+// The result is serialized in JSON format containing either kid or jwk
+// fields based on the provided keyID value.
+//
+// If kid is non-empty, its quoted value is inserted in the protected head
+// as "kid" field value. Otherwise, JWK is computed using jwkEncode and inserted
+// as "jwk" field value. The "jwk" and "kid" fields are mutually exclusive.
+//
+// See https://tools.ietf.org/html/rfc7515#section-7.
+func jwsEncodeJSON(claimset interface{}, key crypto.Signer, kid keyID, nonce, url string) ([]byte, error) {
+	alg, sha := jwsHasher(key.Public())
+	if alg == "" || !sha.Available() {
+		return nil, ErrUnsupportedKey
+	}
+	var phead string
+	switch kid {
+	case noKeyID:
+		jwk, err := jwkEncode(key.Public())
+		if err != nil {
+			return nil, err
+		}
+		phead = fmt.Sprintf(`{"alg":%q,"jwk":%s,"nonce":%q,"url":%q}`, alg, jwk, nonce, url)
+	default:
+		phead = fmt.Sprintf(`{"alg":%q,"kid":%q,"nonce":%q,"url":%q}`, alg, kid, nonce, url)
+	}
+	phead = base64.RawURLEncoding.EncodeToString([]byte(phead))
+	var payload string
+	if claimset != noPayload {
+		cs, err := json.Marshal(claimset)
+		if err != nil {
+			return nil, err
+		}
+		payload = base64.RawURLEncoding.EncodeToString(cs)
+	}
+	hash := sha.New()
+	hash.Write([]byte(phead + "." + payload))
+	sig, err := jwsSign(key, sha, hash.Sum(nil))
+	if err != nil {
+		return nil, err
+	}
+	enc := jsonWebSignature{
+		Protected: phead,
+		Payload:   payload,
+		Sig:       base64.RawURLEncoding.EncodeToString(sig),
+	}
+	return json.Marshal(&enc)
+}
+
+// jwsWithMAC creates and signs a JWS using the given key and the HS256
+// algorithm. kid and url are included in the protected header. rawPayload
+// should not be base64-URL-encoded.
+func jwsWithMAC(key []byte, kid, url string, rawPayload []byte) (*jsonWebSignature, error) {
+	if len(key) == 0 {
+		return nil, errors.New("acme: cannot sign JWS with an empty MAC key")
+	}
+	header := struct {
+		Algorithm string `json:"alg"`
+		KID       string `json:"kid"`
+		URL       string `json:"url,omitempty"`
+	}{
+		// Only HMAC-SHA256 is supported.
+		Algorithm: "HS256",
+		KID:       kid,
+		URL:       url,
+	}
+	rawProtected, err := json.Marshal(header)
+	if err != nil {
+		return nil, err
+	}
+	protected := base64.RawURLEncoding.EncodeToString(rawProtected)
+	payload := base64.RawURLEncoding.EncodeToString(rawPayload)
+
+	h := hmac.New(sha256.New, key)
+	if _, err := h.Write([]byte(protected + "." + payload)); err != nil {
+		return nil, err
+	}
+	mac := h.Sum(nil)
+
+	return &jsonWebSignature{
+		Protected: protected,
+		Payload:   payload,
+		Sig:       base64.RawURLEncoding.EncodeToString(mac),
+	}, nil
+}
+
+// jwkEncode encodes public part of an RSA or ECDSA key into a JWK.
+// The result is also suitable for creating a JWK thumbprint.
+// https://tools.ietf.org/html/rfc7517
+func jwkEncode(pub crypto.PublicKey) (string, error) {
+	switch pub := pub.(type) {
+	case *rsa.PublicKey:
+		// https://tools.ietf.org/html/rfc7518#section-6.3.1
+		n := pub.N
+		e := big.NewInt(int64(pub.E))
+		// Field order is important.
+		// See https://tools.ietf.org/html/rfc7638#section-3.3 for details.
+		return fmt.Sprintf(`{"e":"%s","kty":"RSA","n":"%s"}`,
+			base64.RawURLEncoding.EncodeToString(e.Bytes()),
+			base64.RawURLEncoding.EncodeToString(n.Bytes()),
+		), nil
+	case *ecdsa.PublicKey:
+		// https://tools.ietf.org/html/rfc7518#section-6.2.1
+		p := pub.Curve.Params()
+		n := p.BitSize / 8
+		if p.BitSize%8 != 0 {
+			n++
+		}
+		x := pub.X.Bytes()
+		if n > len(x) {
+			x = append(make([]byte, n-len(x)), x...)
+		}
+		y := pub.Y.Bytes()
+		if n > len(y) {
+			y = append(make([]byte, n-len(y)), y...)
+		}
+		// Field order is important.
+		// See https://tools.ietf.org/html/rfc7638#section-3.3 for details.
+		return fmt.Sprintf(`{"crv":"%s","kty":"EC","x":"%s","y":"%s"}`,
+			p.Name,
+			base64.RawURLEncoding.EncodeToString(x),
+			base64.RawURLEncoding.EncodeToString(y),
+		), nil
+	}
+	return "", ErrUnsupportedKey
+}
+
+// jwsSign signs the digest using the given key.
+// The hash is unused for ECDSA keys.
+func jwsSign(key crypto.Signer, hash crypto.Hash, digest []byte) ([]byte, error) {
+	switch pub := key.Public().(type) {
+	case *rsa.PublicKey:
+		return key.Sign(rand.Reader, digest, hash)
+	case *ecdsa.PublicKey:
+		sigASN1, err := key.Sign(rand.Reader, digest, hash)
+		if err != nil {
+			return nil, err
+		}
+
+		var rs struct{ R, S *big.Int }
+		if _, err := asn1.Unmarshal(sigASN1, &rs); err != nil {
+			return nil, err
+		}
+
+		rb, sb := rs.R.Bytes(), rs.S.Bytes()
+		size := pub.Params().BitSize / 8
+		if size%8 > 0 {
+			size++
+		}
+		sig := make([]byte, size*2)
+		copy(sig[size-len(rb):], rb)
+		copy(sig[size*2-len(sb):], sb)
+		return sig, nil
+	}
+	return nil, ErrUnsupportedKey
+}
+
+// jwsHasher indicates suitable JWS algorithm name and a hash function
+// to use for signing a digest with the provided key.
+// It returns ("", 0) if the key is not supported.
+func jwsHasher(pub crypto.PublicKey) (string, crypto.Hash) {
+	switch pub := pub.(type) {
+	case *rsa.PublicKey:
+		return "RS256", crypto.SHA256
+	case *ecdsa.PublicKey:
+		switch pub.Params().Name {
+		case "P-256":
+			return "ES256", crypto.SHA256
+		case "P-384":
+			return "ES384", crypto.SHA384
+		case "P-521":
+			return "ES512", crypto.SHA512
+		}
+	}
+	return "", 0
+}
+
+// JWKThumbprint creates a JWK thumbprint out of pub
+// as specified in https://tools.ietf.org/html/rfc7638.
+func JWKThumbprint(pub crypto.PublicKey) (string, error) {
+	jwk, err := jwkEncode(pub)
+	if err != nil {
+		return "", err
+	}
+	b := sha256.Sum256([]byte(jwk))
+	return base64.RawURLEncoding.EncodeToString(b[:]), nil
+}

vendor/golang.org/x/crypto/acme/rfc8555.go

@@ -0,0 +1,412 @@
+// Copyright 2019 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 acme
+
+import (
+	"context"
+	"crypto"
+	"encoding/base64"
+	"encoding/json"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"time"
+)
+
+// DeactivateReg permanently disables an existing account associated with c.Key.
+// A deactivated account can no longer request certificate issuance or access
+// resources related to the account, such as orders or authorizations.
+//
+// It only works with CAs implementing RFC 8555.
+func (c *Client) DeactivateReg(ctx context.Context) error {
+	url := string(c.accountKID(ctx))
+	if url == "" {
+		return ErrNoAccount
+	}
+	req := json.RawMessage(`{"status": "deactivated"}`)
+	res, err := c.post(ctx, nil, url, req, wantStatus(http.StatusOK))
+	if err != nil {
+		return err
+	}
+	res.Body.Close()
+	return nil
+}
+
+// registerRFC is equivalent to c.Register but for CAs implementing RFC 8555.
+// It expects c.Discover to have already been called.
+func (c *Client) registerRFC(ctx context.Context, acct *Account, prompt func(tosURL string) bool) (*Account, error) {
+	c.cacheMu.Lock() // guard c.kid access
+	defer c.cacheMu.Unlock()
+
+	req := struct {
+		TermsAgreed            bool              `json:"termsOfServiceAgreed,omitempty"`
+		Contact                []string          `json:"contact,omitempty"`
+		ExternalAccountBinding *jsonWebSignature `json:"externalAccountBinding,omitempty"`
+	}{
+		Contact: acct.Contact,
+	}
+	if c.dir.Terms != "" {
+		req.TermsAgreed = prompt(c.dir.Terms)
+	}
+
+	// set 'externalAccountBinding' field if requested
+	if acct.ExternalAccountBinding != nil {
+		eabJWS, err := c.encodeExternalAccountBinding(acct.ExternalAccountBinding)
+		if err != nil {
+			return nil, fmt.Errorf("acme: failed to encode external account binding: %v", err)
+		}
+		req.ExternalAccountBinding = eabJWS
+	}
+
+	res, err := c.post(ctx, c.Key, c.dir.RegURL, req, wantStatus(
+		http.StatusOK,      // account with this key already registered
+		http.StatusCreated, // new account created
+	))
+	if err != nil {
+		return nil, err
+	}
+
+	defer res.Body.Close()
+	a, err := responseAccount(res)
+	if err != nil {
+		return nil, err
+	}
+	// Cache Account URL even if we return an error to the caller.
+	// It is by all means a valid and usable "kid" value for future requests.
+	c.kid = keyID(a.URI)
+	if res.StatusCode == http.StatusOK {
+		return nil, ErrAccountAlreadyExists
+	}
+	return a, nil
+}
+
+// encodeExternalAccountBinding will encode an external account binding stanza
+// as described in https://tools.ietf.org/html/rfc8555#section-7.3.4.
+func (c *Client) encodeExternalAccountBinding(eab *ExternalAccountBinding) (*jsonWebSignature, error) {
+	jwk, err := jwkEncode(c.Key.Public())
+	if err != nil {
+		return nil, err
+	}
+	return jwsWithMAC(eab.Key, eab.KID, c.dir.RegURL, []byte(jwk))
+}
+
+// updateRegRFC is equivalent to c.UpdateReg but for CAs implementing RFC 8555.
+// It expects c.Discover to have already been called.
+func (c *Client) updateRegRFC(ctx context.Context, a *Account) (*Account, error) {
+	url := string(c.accountKID(ctx))
+	if url == "" {
+		return nil, ErrNoAccount
+	}
+	req := struct {
+		Contact []string `json:"contact,omitempty"`
+	}{
+		Contact: a.Contact,
+	}
+	res, err := c.post(ctx, nil, url, req, wantStatus(http.StatusOK))
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+	return responseAccount(res)
+}
+
+// getGegRFC is equivalent to c.GetReg but for CAs implementing RFC 8555.
+// It expects c.Discover to have already been called.
+func (c *Client) getRegRFC(ctx context.Context) (*Account, error) {
+	req := json.RawMessage(`{"onlyReturnExisting": true}`)
+	res, err := c.post(ctx, c.Key, c.dir.RegURL, req, wantStatus(http.StatusOK))
+	if e, ok := err.(*Error); ok && e.ProblemType == "urn:ietf:params:acme:error:accountDoesNotExist" {
+		return nil, ErrNoAccount
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	defer res.Body.Close()
+	return responseAccount(res)
+}
+
+func responseAccount(res *http.Response) (*Account, error) {
+	var v struct {
+		Status  string
+		Contact []string
+		Orders  string
+	}
+	if err := json.NewDecoder(res.Body).Decode(&v); err != nil {
+		return nil, fmt.Errorf("acme: invalid account response: %v", err)
+	}
+	return &Account{
+		URI:       res.Header.Get("Location"),
+		Status:    v.Status,
+		Contact:   v.Contact,
+		OrdersURL: v.Orders,
+	}, nil
+}
+
+// AuthorizeOrder initiates the order-based application for certificate issuance,
+// as opposed to pre-authorization in Authorize.
+// It is only supported by CAs implementing RFC 8555.
+//
+// The caller then needs to fetch each authorization with GetAuthorization,
+// identify those with StatusPending status and fulfill a challenge using Accept.
+// Once all authorizations are satisfied, the caller will typically want to poll
+// order status using WaitOrder until it's in StatusReady state.
+// To finalize the order and obtain a certificate, the caller submits a CSR with CreateOrderCert.
+func (c *Client) AuthorizeOrder(ctx context.Context, id []AuthzID, opt ...OrderOption) (*Order, error) {
+	dir, err := c.Discover(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	req := struct {
+		Identifiers []wireAuthzID `json:"identifiers"`
+		NotBefore   string        `json:"notBefore,omitempty"`
+		NotAfter    string        `json:"notAfter,omitempty"`
+	}{}
+	for _, v := range id {
+		req.Identifiers = append(req.Identifiers, wireAuthzID{
+			Type:  v.Type,
+			Value: v.Value,
+		})
+	}
+	for _, o := range opt {
+		switch o := o.(type) {
+		case orderNotBeforeOpt:
+			req.NotBefore = time.Time(o).Format(time.RFC3339)
+		case orderNotAfterOpt:
+			req.NotAfter = time.Time(o).Format(time.RFC3339)
+		default:
+			// Package's fault if we let this happen.
+			panic(fmt.Sprintf("unsupported order option type %T", o))
+		}
+	}
+
+	res, err := c.post(ctx, nil, dir.OrderURL, req, wantStatus(http.StatusCreated))
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+	return responseOrder(res)
+}
+
+// GetOrder retrives an order identified by the given URL.
+// For orders created with AuthorizeOrder, the url value is Order.URI.
+//
+// If a caller needs to poll an order until its status is final,
+// see the WaitOrder method.
+func (c *Client) GetOrder(ctx context.Context, url string) (*Order, error) {
+	if _, err := c.Discover(ctx); err != nil {
+		return nil, err
+	}
+
+	res, err := c.postAsGet(ctx, url, wantStatus(http.StatusOK))
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+	return responseOrder(res)
+}
+
+// WaitOrder polls an order from the given URL until it is in one of the final states,
+// StatusReady, StatusValid or StatusInvalid, the CA responded with a non-retryable error
+// or the context is done.
+//
+// It returns a non-nil Order only if its Status is StatusReady or StatusValid.
+// In all other cases WaitOrder returns an error.
+// If the Status is StatusInvalid, the returned error is of type *OrderError.
+func (c *Client) WaitOrder(ctx context.Context, url string) (*Order, error) {
+	if _, err := c.Discover(ctx); err != nil {
+		return nil, err
+	}
+	for {
+		res, err := c.postAsGet(ctx, url, wantStatus(http.StatusOK))
+		if err != nil {
+			return nil, err
+		}
+		o, err := responseOrder(res)
+		res.Body.Close()
+		switch {
+		case err != nil:
+			// Skip and retry.
+		case o.Status == StatusInvalid:
+			return nil, &OrderError{OrderURL: o.URI, Status: o.Status}
+		case o.Status == StatusReady || o.Status == StatusValid:
+			return o, nil
+		}
+
+		d := retryAfter(res.Header.Get("Retry-After"))
+		if d == 0 {
+			// Default retry-after.
+			// Same reasoning as in WaitAuthorization.
+			d = time.Second
+		}
+		t := time.NewTimer(d)
+		select {
+		case <-ctx.Done():
+			t.Stop()
+			return nil, ctx.Err()
+		case <-t.C:
+			// Retry.
+		}
+	}
+}
+
+func responseOrder(res *http.Response) (*Order, error) {
+	var v struct {
+		Status         string
+		Expires        time.Time
+		Identifiers    []wireAuthzID
+		NotBefore      time.Time
+		NotAfter       time.Time
+		Error          *wireError
+		Authorizations []string
+		Finalize       string
+		Certificate    string
+	}
+	if err := json.NewDecoder(res.Body).Decode(&v); err != nil {
+		return nil, fmt.Errorf("acme: error reading order: %v", err)
+	}
+	o := &Order{
+		URI:         res.Header.Get("Location"),
+		Status:      v.Status,
+		Expires:     v.Expires,
+		NotBefore:   v.NotBefore,
+		NotAfter:    v.NotAfter,
+		AuthzURLs:   v.Authorizations,
+		FinalizeURL: v.Finalize,
+		CertURL:     v.Certificate,
+	}
+	for _, id := range v.Identifiers {
+		o.Identifiers = append(o.Identifiers, AuthzID{Type: id.Type, Value: id.Value})
+	}
+	if v.Error != nil {
+		o.Error = v.Error.error(nil /* headers */)
+	}
+	return o, nil
+}
+
+// CreateOrderCert submits the CSR (Certificate Signing Request) to a CA at the specified URL.
+// The URL is the FinalizeURL field of an Order created with AuthorizeOrder.
+//
+// If the bundle argument is true, the returned value also contain the CA (issuer)
+// certificate chain. Otherwise, only a leaf certificate is returned.
+// The returned URL can be used to re-fetch the certificate using FetchCert.
+//
+// This method is only supported by CAs implementing RFC 8555. See CreateCert for pre-RFC CAs.
+//
+// CreateOrderCert returns an error if the CA's response is unreasonably large.
+// Callers are encouraged to parse the returned value to ensure the certificate is valid and has the expected features.
+func (c *Client) CreateOrderCert(ctx context.Context, url string, csr []byte, bundle bool) (der [][]byte, certURL string, err error) {
+	if _, err := c.Discover(ctx); err != nil { // required by c.accountKID
+		return nil, "", err
+	}
+
+	// RFC describes this as "finalize order" request.
+	req := struct {
+		CSR string `json:"csr"`
+	}{
+		CSR: base64.RawURLEncoding.EncodeToString(csr),
+	}
+	res, err := c.post(ctx, nil, url, req, wantStatus(http.StatusOK))
+	if err != nil {
+		return nil, "", err
+	}
+	defer res.Body.Close()
+	o, err := responseOrder(res)
+	if err != nil {
+		return nil, "", err
+	}
+
+	// Wait for CA to issue the cert if they haven't.
+	if o.Status != StatusValid {
+		o, err = c.WaitOrder(ctx, o.URI)
+	}
+	if err != nil {
+		return nil, "", err
+	}
+	// The only acceptable status post finalize and WaitOrder is "valid".
+	if o.Status != StatusValid {
+		return nil, "", &OrderError{OrderURL: o.URI, Status: o.Status}
+	}
+	crt, err := c.fetchCertRFC(ctx, o.CertURL, bundle)
+	return crt, o.CertURL, err
+}
+
+// fetchCertRFC downloads issued certificate from the given URL.
+// It expects the CA to respond with PEM-encoded certificate chain.
+//
+// The URL argument is the CertURL field of Order.
+func (c *Client) fetchCertRFC(ctx context.Context, url string, bundle bool) ([][]byte, error) {
+	res, err := c.postAsGet(ctx, url, wantStatus(http.StatusOK))
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	// Get all the bytes up to a sane maximum.
+	// Account very roughly for base64 overhead.
+	const max = maxCertChainSize + maxCertChainSize/33
+	b, err := ioutil.ReadAll(io.LimitReader(res.Body, max+1))
+	if err != nil {
+		return nil, fmt.Errorf("acme: fetch cert response stream: %v", err)
+	}
+	if len(b) > max {
+		return nil, errors.New("acme: certificate chain is too big")
+	}
+
+	// Decode PEM chain.
+	var chain [][]byte
+	for {
+		var p *pem.Block
+		p, b = pem.Decode(b)
+		if p == nil {
+			break
+		}
+		if p.Type != "CERTIFICATE" {
+			return nil, fmt.Errorf("acme: invalid PEM cert type %q", p.Type)
+		}
+
+		chain = append(chain, p.Bytes)
+		if !bundle {
+			return chain, nil
+		}
+		if len(chain) > maxChainLen {
+			return nil, errors.New("acme: certificate chain is too long")
+		}
+	}
+	if len(chain) == 0 {
+		return nil, errors.New("acme: certificate chain is empty")
+	}
+	return chain, nil
+}
+
+// sends a cert revocation request in either JWK form when key is non-nil or KID form otherwise.
+func (c *Client) revokeCertRFC(ctx context.Context, key crypto.Signer, cert []byte, reason CRLReasonCode) error {
+	req := &struct {
+		Cert   string `json:"certificate"`
+		Reason int    `json:"reason"`
+	}{
+		Cert:   base64.RawURLEncoding.EncodeToString(cert),
+		Reason: int(reason),
+	}
+	res, err := c.post(ctx, key, c.dir.RevokeURL, req, wantStatus(http.StatusOK))
+	if err != nil {
+		if isAlreadyRevoked(err) {
+			// Assume it is not an error to revoke an already revoked cert.
+			return nil
+		}
+		return err
+	}
+	defer res.Body.Close()
+	return nil
+}
+
+func isAlreadyRevoked(err error) bool {
+	e, ok := err.(*Error)
+	return ok && e.ProblemType == "urn:ietf:params:acme:error:alreadyRevoked"
+}

vendor/golang.org/x/crypto/acme/types.go

@@ -0,0 +1,582 @@
+// 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 acme
+
+import (
+	"crypto"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+)
+
+// ACME status values of Account, Order, Authorization and Challenge objects.
+// See https://tools.ietf.org/html/rfc8555#section-7.1.6 for details.
+const (
+	StatusDeactivated = "deactivated"
+	StatusExpired     = "expired"
+	StatusInvalid     = "invalid"
+	StatusPending     = "pending"
+	StatusProcessing  = "processing"
+	StatusReady       = "ready"
+	StatusRevoked     = "revoked"
+	StatusUnknown     = "unknown"
+	StatusValid       = "valid"
+)
+
+// CRLReasonCode identifies the reason for a certificate revocation.
+type CRLReasonCode int
+
+// CRL reason codes as defined in RFC 5280.
+const (
+	CRLReasonUnspecified          CRLReasonCode = 0
+	CRLReasonKeyCompromise        CRLReasonCode = 1
+	CRLReasonCACompromise         CRLReasonCode = 2
+	CRLReasonAffiliationChanged   CRLReasonCode = 3
+	CRLReasonSuperseded           CRLReasonCode = 4
+	CRLReasonCessationOfOperation CRLReasonCode = 5
+	CRLReasonCertificateHold      CRLReasonCode = 6
+	CRLReasonRemoveFromCRL        CRLReasonCode = 8
+	CRLReasonPrivilegeWithdrawn   CRLReasonCode = 9
+	CRLReasonAACompromise         CRLReasonCode = 10
+)
+
+var (
+	// ErrUnsupportedKey is returned when an unsupported key type is encountered.
+	ErrUnsupportedKey = errors.New("acme: unknown key type; only RSA and ECDSA are supported")
+
+	// ErrAccountAlreadyExists indicates that the Client's key has already been registered
+	// with the CA. It is returned by Register method.
+	ErrAccountAlreadyExists = errors.New("acme: account already exists")
+
+	// ErrNoAccount indicates that the Client's key has not been registered with the CA.
+	ErrNoAccount = errors.New("acme: account does not exist")
+)
+
+// Error is an ACME error, defined in Problem Details for HTTP APIs doc
+// http://tools.ietf.org/html/draft-ietf-appsawg-http-problem.
+type Error struct {
+	// StatusCode is The HTTP status code generated by the origin server.
+	StatusCode int
+	// ProblemType is a URI reference that identifies the problem type,
+	// typically in a "urn:acme:error:xxx" form.
+	ProblemType string
+	// Detail is a human-readable explanation specific to this occurrence of the problem.
+	Detail string
+	// Instance indicates a URL that the client should direct a human user to visit
+	// in order for instructions on how to agree to the updated Terms of Service.
+	// In such an event CA sets StatusCode to 403, ProblemType to
+	// "urn:ietf:params:acme:error:userActionRequired" and a Link header with relation
+	// "terms-of-service" containing the latest TOS URL.
+	Instance string
+	// Header is the original server error response headers.
+	// It may be nil.
+	Header http.Header
+}
+
+func (e *Error) Error() string {
+	return fmt.Sprintf("%d %s: %s", e.StatusCode, e.ProblemType, e.Detail)
+}
+
+// AuthorizationError indicates that an authorization for an identifier
+// did not succeed.
+// It contains all errors from Challenge items of the failed Authorization.
+type AuthorizationError struct {
+	// URI uniquely identifies the failed Authorization.
+	URI string
+
+	// Identifier is an AuthzID.Value of the failed Authorization.
+	Identifier string
+
+	// Errors is a collection of non-nil error values of Challenge items
+	// of the failed Authorization.
+	Errors []error
+}
+
+func (a *AuthorizationError) Error() string {
+	e := make([]string, len(a.Errors))
+	for i, err := range a.Errors {
+		e[i] = err.Error()
+	}
+
+	if a.Identifier != "" {
+		return fmt.Sprintf("acme: authorization error for %s: %s", a.Identifier, strings.Join(e, "; "))
+	}
+
+	return fmt.Sprintf("acme: authorization error: %s", strings.Join(e, "; "))
+}
+
+// OrderError is returned from Client's order related methods.
+// It indicates the order is unusable and the clients should start over with
+// AuthorizeOrder.
+//
+// The clients can still fetch the order object from CA using GetOrder
+// to inspect its state.
+type OrderError struct {
+	OrderURL string
+	Status   string
+}
+
+func (oe *OrderError) Error() string {
+	return fmt.Sprintf("acme: order %s status: %s", oe.OrderURL, oe.Status)
+}
+
+// RateLimit reports whether err represents a rate limit error and
+// any Retry-After duration returned by the server.
+//
+// See the following for more details on rate limiting:
+// https://tools.ietf.org/html/draft-ietf-acme-acme-05#section-5.6
+func RateLimit(err error) (time.Duration, bool) {
+	e, ok := err.(*Error)
+	if !ok {
+		return 0, false
+	}
+	// Some CA implementations may return incorrect values.
+	// Use case-insensitive comparison.
+	if !strings.HasSuffix(strings.ToLower(e.ProblemType), ":ratelimited") {
+		return 0, false
+	}
+	if e.Header == nil {
+		return 0, true
+	}
+	return retryAfter(e.Header.Get("Retry-After")), true
+}
+
+// Account is a user account. It is associated with a private key.
+// Non-RFC 8555 fields are empty when interfacing with a compliant CA.
+type Account struct {
+	// URI is the account unique ID, which is also a URL used to retrieve
+	// account data from the CA.
+	// When interfacing with RFC 8555-compliant CAs, URI is the "kid" field
+	// value in JWS signed requests.
+	URI string
+
+	// Contact is a slice of contact info used during registration.
+	// See https://tools.ietf.org/html/rfc8555#section-7.3 for supported
+	// formats.
+	Contact []string
+
+	// Status indicates current account status as returned by the CA.
+	// Possible values are StatusValid, StatusDeactivated, and StatusRevoked.
+	Status string
+
+	// OrdersURL is a URL from which a list of orders submitted by this account
+	// can be fetched.
+	OrdersURL string
+
+	// The terms user has agreed to.
+	// A value not matching CurrentTerms indicates that the user hasn't agreed
+	// to the actual Terms of Service of the CA.
+	//
+	// It is non-RFC 8555 compliant. Package users can store the ToS they agree to
+	// during Client's Register call in the prompt callback function.
+	AgreedTerms string
+
+	// Actual terms of a CA.
+	//
+	// It is non-RFC 8555 compliant. Use Directory's Terms field.
+	// When a CA updates their terms and requires an account agreement,
+	// a URL at which instructions to do so is available in Error's Instance field.
+	CurrentTerms string
+
+	// Authz is the authorization URL used to initiate a new authz flow.
+	//
+	// It is non-RFC 8555 compliant. Use Directory's AuthzURL or OrderURL.
+	Authz string
+
+	// Authorizations is a URI from which a list of authorizations
+	// granted to this account can be fetched via a GET request.
+	//
+	// It is non-RFC 8555 compliant and is obsoleted by OrdersURL.
+	Authorizations string
+
+	// Certificates is a URI from which a list of certificates
+	// issued for this account can be fetched via a GET request.
+	//
+	// It is non-RFC 8555 compliant and is obsoleted by OrdersURL.
+	Certificates string
+
+	// ExternalAccountBinding represents an arbitrary binding to an account of
+	// the CA which the ACME server is tied to.
+	// See https://tools.ietf.org/html/rfc8555#section-7.3.4 for more details.
+	ExternalAccountBinding *ExternalAccountBinding
+}
+
+// ExternalAccountBinding contains the data needed to form a request with
+// an external account binding.
+// See https://tools.ietf.org/html/rfc8555#section-7.3.4 for more details.
+type ExternalAccountBinding struct {
+	// KID is the Key ID of the symmetric MAC key that the CA provides to
+	// identify an external account from ACME.
+	KID string
+
+	// Key is the bytes of the symmetric key that the CA provides to identify
+	// the account. Key must correspond to the KID.
+	Key []byte
+}
+
+func (e *ExternalAccountBinding) String() string {
+	return fmt.Sprintf("&{KID: %q, Key: redacted}", e.KID)
+}
+
+// Directory is ACME server discovery data.
+// See https://tools.ietf.org/html/rfc8555#section-7.1.1 for more details.
+type Directory struct {
+	// NonceURL indicates an endpoint where to fetch fresh nonce values from.
+	NonceURL string
+
+	// RegURL is an account endpoint URL, allowing for creating new accounts.
+	// Pre-RFC 8555 CAs also allow modifying existing accounts at this URL.
+	RegURL string
+
+	// OrderURL is used to initiate the certificate issuance flow
+	// as described in RFC 8555.
+	OrderURL string
+
+	// AuthzURL is used to initiate identifier pre-authorization flow.
+	// Empty string indicates the flow is unsupported by the CA.
+	AuthzURL string
+
+	// CertURL is a new certificate issuance endpoint URL.
+	// It is non-RFC 8555 compliant and is obsoleted by OrderURL.
+	CertURL string
+
+	// RevokeURL is used to initiate a certificate revocation flow.
+	RevokeURL string
+
+	// KeyChangeURL allows to perform account key rollover flow.
+	KeyChangeURL string
+
+	// Term is a URI identifying the current terms of service.
+	Terms string
+
+	// Website is an HTTP or HTTPS URL locating a website
+	// providing more information about the ACME server.
+	Website string
+
+	// CAA consists of lowercase hostname elements, which the ACME server
+	// recognises as referring to itself for the purposes of CAA record validation
+	// as defined in RFC6844.
+	CAA []string
+
+	// ExternalAccountRequired indicates that the CA requires for all account-related
+	// requests to include external account binding information.
+	ExternalAccountRequired bool
+}
+
+// rfcCompliant reports whether the ACME server implements RFC 8555.
+// Note that some servers may have incomplete RFC implementation
+// even if the returned value is true.
+// If rfcCompliant reports false, the server most likely implements draft-02.
+func (d *Directory) rfcCompliant() bool {
+	return d.OrderURL != ""
+}
+
+// Order represents a client's request for a certificate.
+// It tracks the request flow progress through to issuance.
+type Order struct {
+	// URI uniquely identifies an order.
+	URI string
+
+	// Status represents the current status of the order.
+	// It indicates which action the client should take.
+	//
+	// Possible values are StatusPending, StatusReady, StatusProcessing, StatusValid and StatusInvalid.
+	// Pending means the CA does not believe that the client has fulfilled the requirements.
+	// Ready indicates that the client has fulfilled all the requirements and can submit a CSR
+	// to obtain a certificate. This is done with Client's CreateOrderCert.
+	// Processing means the certificate is being issued.
+	// Valid indicates the CA has issued the certificate. It can be downloaded
+	// from the Order's CertURL. This is done with Client's FetchCert.
+	// Invalid means the certificate will not be issued. Users should consider this order
+	// abandoned.
+	Status string
+
+	// Expires is the timestamp after which CA considers this order invalid.
+	Expires time.Time
+
+	// Identifiers contains all identifier objects which the order pertains to.
+	Identifiers []AuthzID
+
+	// NotBefore is the requested value of the notBefore field in the certificate.
+	NotBefore time.Time
+
+	// NotAfter is the requested value of the notAfter field in the certificate.
+	NotAfter time.Time
+
+	// AuthzURLs represents authorizations to complete before a certificate
+	// for identifiers specified in the order can be issued.
+	// It also contains unexpired authorizations that the client has completed
+	// in the past.
+	//
+	// Authorization objects can be fetched using Client's GetAuthorization method.
+	//
+	// The required authorizations are dictated by CA policies.
+	// There may not be a 1:1 relationship between the identifiers and required authorizations.
+	// Required authorizations can be identified by their StatusPending status.
+	//
+	// For orders in the StatusValid or StatusInvalid state these are the authorizations
+	// which were completed.
+	AuthzURLs []string
+
+	// FinalizeURL is the endpoint at which a CSR is submitted to obtain a certificate
+	// once all the authorizations are satisfied.
+	FinalizeURL string
+
+	// CertURL points to the certificate that has been issued in response to this order.
+	CertURL string
+
+	// The error that occurred while processing the order as received from a CA, if any.
+	Error *Error
+}
+
+// OrderOption allows customizing Client.AuthorizeOrder call.
+type OrderOption interface {
+	privateOrderOpt()
+}
+
+// WithOrderNotBefore sets order's NotBefore field.
+func WithOrderNotBefore(t time.Time) OrderOption {
+	return orderNotBeforeOpt(t)
+}
+
+// WithOrderNotAfter sets order's NotAfter field.
+func WithOrderNotAfter(t time.Time) OrderOption {
+	return orderNotAfterOpt(t)
+}
+
+type orderNotBeforeOpt time.Time
+
+func (orderNotBeforeOpt) privateOrderOpt() {}
+
+type orderNotAfterOpt time.Time
+
+func (orderNotAfterOpt) privateOrderOpt() {}
+
+// Authorization encodes an authorization response.
+type Authorization struct {
+	// URI uniquely identifies a authorization.
+	URI string
+
+	// Status is the current status of an authorization.
+	// Possible values are StatusPending, StatusValid, StatusInvalid, StatusDeactivated,
+	// StatusExpired and StatusRevoked.
+	Status string
+
+	// Identifier is what the account is authorized to represent.
+	Identifier AuthzID
+
+	// The timestamp after which the CA considers the authorization invalid.
+	Expires time.Time
+
+	// Wildcard is true for authorizations of a wildcard domain name.
+	Wildcard bool
+
+	// Challenges that the client needs to fulfill in order to prove possession
+	// of the identifier (for pending authorizations).
+	// For valid authorizations, the challenge that was validated.
+	// For invalid authorizations, the challenge that was attempted and failed.
+	//
+	// RFC 8555 compatible CAs require users to fuflfill only one of the challenges.
+	Challenges []*Challenge
+
+	// A collection of sets of challenges, each of which would be sufficient
+	// to prove possession of the identifier.
+	// Clients must complete a set of challenges that covers at least one set.
+	// Challenges are identified by their indices in the challenges array.
+	// If this field is empty, the client needs to complete all challenges.
+	//
+	// This field is unused in RFC 8555.
+	Combinations [][]int
+}
+
+// AuthzID is an identifier that an account is authorized to represent.
+type AuthzID struct {
+	Type  string // The type of identifier, "dns" or "ip".
+	Value string // The identifier itself, e.g. "example.org".
+}
+
+// DomainIDs creates a slice of AuthzID with "dns" identifier type.
+func DomainIDs(names ...string) []AuthzID {
+	a := make([]AuthzID, len(names))
+	for i, v := range names {
+		a[i] = AuthzID{Type: "dns", Value: v}
+	}
+	return a
+}
+
+// IPIDs creates a slice of AuthzID with "ip" identifier type.
+// Each element of addr is textual form of an address as defined
+// in RFC1123 Section 2.1 for IPv4 and in RFC5952 Section 4 for IPv6.
+func IPIDs(addr ...string) []AuthzID {
+	a := make([]AuthzID, len(addr))
+	for i, v := range addr {
+		a[i] = AuthzID{Type: "ip", Value: v}
+	}
+	return a
+}
+
+// wireAuthzID is ACME JSON representation of authorization identifier objects.
+type wireAuthzID struct {
+	Type  string `json:"type"`
+	Value string `json:"value"`
+}
+
+// wireAuthz is ACME JSON representation of Authorization objects.
+type wireAuthz struct {
+	Identifier   wireAuthzID
+	Status       string
+	Expires      time.Time
+	Wildcard     bool
+	Challenges   []wireChallenge
+	Combinations [][]int
+	Error        *wireError
+}
+
+func (z *wireAuthz) authorization(uri string) *Authorization {
+	a := &Authorization{
+		URI:          uri,
+		Status:       z.Status,
+		Identifier:   AuthzID{Type: z.Identifier.Type, Value: z.Identifier.Value},
+		Expires:      z.Expires,
+		Wildcard:     z.Wildcard,
+		Challenges:   make([]*Challenge, len(z.Challenges)),
+		Combinations: z.Combinations, // shallow copy
+	}
+	for i, v := range z.Challenges {
+		a.Challenges[i] = v.challenge()
+	}
+	return a
+}
+
+func (z *wireAuthz) error(uri string) *AuthorizationError {
+	err := &AuthorizationError{
+		URI:        uri,
+		Identifier: z.Identifier.Value,
+	}
+
+	if z.Error != nil {
+		err.Errors = append(err.Errors, z.Error.error(nil))
+	}
+
+	for _, raw := range z.Challenges {
+		if raw.Error != nil {
+			err.Errors = append(err.Errors, raw.Error.error(nil))
+		}
+	}
+
+	return err
+}
+
+// Challenge encodes a returned CA challenge.
+// Its Error field may be non-nil if the challenge is part of an Authorization
+// with StatusInvalid.
+type Challenge struct {
+	// Type is the challenge type, e.g. "http-01", "tls-alpn-01", "dns-01".
+	Type string
+
+	// URI is where a challenge response can be posted to.
+	URI string
+
+	// Token is a random value that uniquely identifies the challenge.
+	Token string
+
+	// Status identifies the status of this challenge.
+	// In RFC 8555, possible values are StatusPending, StatusProcessing, StatusValid,
+	// and StatusInvalid.
+	Status string
+
+	// Validated is the time at which the CA validated this challenge.
+	// Always zero value in pre-RFC 8555.
+	Validated time.Time
+
+	// Error indicates the reason for an authorization failure
+	// when this challenge was used.
+	// The type of a non-nil value is *Error.
+	Error error
+}
+
+// wireChallenge is ACME JSON challenge representation.
+type wireChallenge struct {
+	URL       string `json:"url"` // RFC
+	URI       string `json:"uri"` // pre-RFC
+	Type      string
+	Token     string
+	Status    string
+	Validated time.Time
+	Error     *wireError
+}
+
+func (c *wireChallenge) challenge() *Challenge {
+	v := &Challenge{
+		URI:    c.URL,
+		Type:   c.Type,
+		Token:  c.Token,
+		Status: c.Status,
+	}
+	if v.URI == "" {
+		v.URI = c.URI // c.URL was empty; use legacy
+	}
+	if v.Status == "" {
+		v.Status = StatusPending
+	}
+	if c.Error != nil {
+		v.Error = c.Error.error(nil)
+	}
+	return v
+}
+
+// wireError is a subset of fields of the Problem Details object
+// as described in https://tools.ietf.org/html/rfc7807#section-3.1.
+type wireError struct {
+	Status   int
+	Type     string
+	Detail   string
+	Instance string
+}
+
+func (e *wireError) error(h http.Header) *Error {
+	return &Error{
+		StatusCode:  e.Status,
+		ProblemType: e.Type,
+		Detail:      e.Detail,
+		Instance:    e.Instance,
+		Header:      h,
+	}
+}
+
+// CertOption is an optional argument type for the TLS ChallengeCert methods for
+// customizing a temporary certificate for TLS-based challenges.
+type CertOption interface {
+	privateCertOpt()
+}
+
+// WithKey creates an option holding a private/public key pair.
+// The private part signs a certificate, and the public part represents the signee.
+func WithKey(key crypto.Signer) CertOption {
+	return &certOptKey{key}
+}
+
+type certOptKey struct {
+	key crypto.Signer
+}
+
+func (*certOptKey) privateCertOpt() {}
+
+// WithTemplate creates an option for specifying a certificate template.
+// See x509.CreateCertificate for template usage details.
+//
+// In TLS ChallengeCert methods, the template is also used as parent,
+// resulting in a self-signed certificate.
+// The DNSNames field of t is always overwritten for tls-sni challenge certs.
+func WithTemplate(t *x509.Certificate) CertOption {
+	return (*certOptTemplate)(t)
+}
+
+type certOptTemplate x509.Certificate
+
+func (*certOptTemplate) privateCertOpt() {}

vendor/golang.org/x/crypto/acme/version_go112.go

@@ -0,0 +1,27 @@
+// Copyright 2019 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.
+
+// +build go1.12
+
+package acme
+
+import "runtime/debug"
+
+func init() {
+	// Set packageVersion if the binary was built in modules mode and x/crypto
+	// was not replaced with a different module.
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return
+	}
+	for _, m := range info.Deps {
+		if m.Path != "golang.org/x/crypto" {
+			continue
+		}
+		if m.Replace == nil {
+			packageVersion = m.Version
+		}
+		break
+	}
+}

vendor/golang.org/x/crypto/bcrypt/base64.go

@@ -0,0 +1,35 @@
+// Copyright 2011 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 bcrypt
+
+import "encoding/base64"
+
+const alphabet = "./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
+
+var bcEncoding = base64.NewEncoding(alphabet)
+
+func base64Encode(src []byte) []byte {
+	n := bcEncoding.EncodedLen(len(src))
+	dst := make([]byte, n)
+	bcEncoding.Encode(dst, src)
+	for dst[n-1] == '=' {
+		n--
+	}
+	return dst[:n]
+}
+
+func base64Decode(src []byte) ([]byte, error) {
+	numOfEquals := 4 - (len(src) % 4)
+	for i := 0; i < numOfEquals; i++ {
+		src = append(src, '=')
+	}
+
+	dst := make([]byte, bcEncoding.DecodedLen(len(src)))
+	n, err := bcEncoding.Decode(dst, src)
+	if err != nil {
+		return nil, err
+	}
+	return dst[:n], nil
+}

vendor/golang.org/x/crypto/bcrypt/bcrypt.go

@@ -0,0 +1,295 @@
+// Copyright 2011 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 bcrypt implements Provos and Mazières's bcrypt adaptive hashing
+// algorithm. See http://www.usenix.org/event/usenix99/provos/provos.pdf
+package bcrypt // import "golang.org/x/crypto/bcrypt"
+
+// The code is a port of Provos and Mazières's C implementation.
+import (
+	"crypto/rand"
+	"crypto/subtle"
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+
+	"golang.org/x/crypto/blowfish"
+)
+
+const (
+	MinCost     int = 4  // the minimum allowable cost as passed in to GenerateFromPassword
+	MaxCost     int = 31 // the maximum allowable cost as passed in to GenerateFromPassword
+	DefaultCost int = 10 // the cost that will actually be set if a cost below MinCost is passed into GenerateFromPassword
+)
+
+// The error returned from CompareHashAndPassword when a password and hash do
+// not match.
+var ErrMismatchedHashAndPassword = errors.New("crypto/bcrypt: hashedPassword is not the hash of the given password")
+
+// The error returned from CompareHashAndPassword when a hash is too short to
+// be a bcrypt hash.
+var ErrHashTooShort = errors.New("crypto/bcrypt: hashedSecret too short to be a bcrypted password")
+
+// The error returned from CompareHashAndPassword when a hash was created with
+// a bcrypt algorithm newer than this implementation.
+type HashVersionTooNewError byte
+
+func (hv HashVersionTooNewError) Error() string {
+	return fmt.Sprintf("crypto/bcrypt: bcrypt algorithm version '%c' requested is newer than current version '%c'", byte(hv), majorVersion)
+}
+
+// The error returned from CompareHashAndPassword when a hash starts with something other than '$'
+type InvalidHashPrefixError byte
+
+func (ih InvalidHashPrefixError) Error() string {
+	return fmt.Sprintf("crypto/bcrypt: bcrypt hashes must start with '$', but hashedSecret started with '%c'", byte(ih))
+}
+
+type InvalidCostError int
+
+func (ic InvalidCostError) Error() string {
+	return fmt.Sprintf("crypto/bcrypt: cost %d is outside allowed range (%d,%d)", int(ic), int(MinCost), int(MaxCost))
+}
+
+const (
+	majorVersion       = '2'
+	minorVersion       = 'a'
+	maxSaltSize        = 16
+	maxCryptedHashSize = 23
+	encodedSaltSize    = 22
+	encodedHashSize    = 31
+	minHashSize        = 59
+)
+
+// magicCipherData is an IV for the 64 Blowfish encryption calls in
+// bcrypt(). It's the string "OrpheanBeholderScryDoubt" in big-endian bytes.
+var magicCipherData = []byte{
+	0x4f, 0x72, 0x70, 0x68,
+	0x65, 0x61, 0x6e, 0x42,
+	0x65, 0x68, 0x6f, 0x6c,
+	0x64, 0x65, 0x72, 0x53,
+	0x63, 0x72, 0x79, 0x44,
+	0x6f, 0x75, 0x62, 0x74,
+}
+
+type hashed struct {
+	hash  []byte
+	salt  []byte
+	cost  int // allowed range is MinCost to MaxCost
+	major byte
+	minor byte
+}
+
+// GenerateFromPassword returns the bcrypt hash of the password at the given
+// cost. If the cost given is less than MinCost, the cost will be set to
+// DefaultCost, instead. Use CompareHashAndPassword, as defined in this package,
+// to compare the returned hashed password with its cleartext version.
+func GenerateFromPassword(password []byte, cost int) ([]byte, error) {
+	p, err := newFromPassword(password, cost)
+	if err != nil {
+		return nil, err
+	}
+	return p.Hash(), nil
+}
+
+// CompareHashAndPassword compares a bcrypt hashed password with its possible
+// plaintext equivalent. Returns nil on success, or an error on failure.
+func CompareHashAndPassword(hashedPassword, password []byte) error {
+	p, err := newFromHash(hashedPassword)
+	if err != nil {
+		return err
+	}
+
+	otherHash, err := bcrypt(password, p.cost, p.salt)
+	if err != nil {
+		return err
+	}
+
+	otherP := &hashed{otherHash, p.salt, p.cost, p.major, p.minor}
+	if subtle.ConstantTimeCompare(p.Hash(), otherP.Hash()) == 1 {
+		return nil
+	}
+
+	return ErrMismatchedHashAndPassword
+}
+
+// Cost returns the hashing cost used to create the given hashed
+// password. When, in the future, the hashing cost of a password system needs
+// to be increased in order to adjust for greater computational power, this
+// function allows one to establish which passwords need to be updated.
+func Cost(hashedPassword []byte) (int, error) {
+	p, err := newFromHash(hashedPassword)
+	if err != nil {
+		return 0, err
+	}
+	return p.cost, nil
+}
+
+func newFromPassword(password []byte, cost int) (*hashed, error) {
+	if cost < MinCost {
+		cost = DefaultCost
+	}
+	p := new(hashed)
+	p.major = majorVersion
+	p.minor = minorVersion
+
+	err := checkCost(cost)
+	if err != nil {
+		return nil, err
+	}
+	p.cost = cost
+
+	unencodedSalt := make([]byte, maxSaltSize)
+	_, err = io.ReadFull(rand.Reader, unencodedSalt)
+	if err != nil {
+		return nil, err
+	}
+
+	p.salt = base64Encode(unencodedSalt)
+	hash, err := bcrypt(password, p.cost, p.salt)
+	if err != nil {
+		return nil, err
+	}
+	p.hash = hash
+	return p, err
+}
+
+func newFromHash(hashedSecret []byte) (*hashed, error) {
+	if len(hashedSecret) < minHashSize {
+		return nil, ErrHashTooShort
+	}
+	p := new(hashed)
+	n, err := p.decodeVersion(hashedSecret)
+	if err != nil {
+		return nil, err
+	}
+	hashedSecret = hashedSecret[n:]
+	n, err = p.decodeCost(hashedSecret)
+	if err != nil {
+		return nil, err
+	}
+	hashedSecret = hashedSecret[n:]
+
+	// The "+2" is here because we'll have to append at most 2 '=' to the salt
+	// when base64 decoding it in expensiveBlowfishSetup().
+	p.salt = make([]byte, encodedSaltSize, encodedSaltSize+2)
+	copy(p.salt, hashedSecret[:encodedSaltSize])
+
+	hashedSecret = hashedSecret[encodedSaltSize:]
+	p.hash = make([]byte, len(hashedSecret))
+	copy(p.hash, hashedSecret)
+
+	return p, nil
+}
+
+func bcrypt(password []byte, cost int, salt []byte) ([]byte, error) {
+	cipherData := make([]byte, len(magicCipherData))
+	copy(cipherData, magicCipherData)
+
+	c, err := expensiveBlowfishSetup(password, uint32(cost), salt)
+	if err != nil {
+		return nil, err
+	}
+
+	for i := 0; i < 24; i += 8 {
+		for j := 0; j < 64; j++ {
+			c.Encrypt(cipherData[i:i+8], cipherData[i:i+8])
+		}
+	}
+
+	// Bug compatibility with C bcrypt implementations. We only encode 23 of
+	// the 24 bytes encrypted.
+	hsh := base64Encode(cipherData[:maxCryptedHashSize])
+	return hsh, nil
+}
+
+func expensiveBlowfishSetup(key []byte, cost uint32, salt []byte) (*blowfish.Cipher, error) {
+	csalt, err := base64Decode(salt)
+	if err != nil {
+		return nil, err
+	}
+
+	// Bug compatibility with C bcrypt implementations. They use the trailing
+	// NULL in the key string during expansion.
+	// We copy the key to prevent changing the underlying array.
+	ckey := append(key[:len(key):len(key)], 0)
+
+	c, err := blowfish.NewSaltedCipher(ckey, csalt)
+	if err != nil {
+		return nil, err
+	}
+
+	var i, rounds uint64
+	rounds = 1 << cost
+	for i = 0; i < rounds; i++ {
+		blowfish.ExpandKey(ckey, c)
+		blowfish.ExpandKey(csalt, c)
+	}
+
+	return c, nil
+}
+
+func (p *hashed) Hash() []byte {
+	arr := make([]byte, 60)
+	arr[0] = '$'
+	arr[1] = p.major
+	n := 2
+	if p.minor != 0 {
+		arr[2] = p.minor
+		n = 3
+	}
+	arr[n] = '$'
+	n++
+	copy(arr[n:], []byte(fmt.Sprintf("%02d", p.cost)))
+	n += 2
+	arr[n] = '$'
+	n++
+	copy(arr[n:], p.salt)
+	n += encodedSaltSize
+	copy(arr[n:], p.hash)
+	n += encodedHashSize
+	return arr[:n]
+}
+
+func (p *hashed) decodeVersion(sbytes []byte) (int, error) {
+	if sbytes[0] != '$' {
+		return -1, InvalidHashPrefixError(sbytes[0])
+	}
+	if sbytes[1] > majorVersion {
+		return -1, HashVersionTooNewError(sbytes[1])
+	}
+	p.major = sbytes[1]
+	n := 3
+	if sbytes[2] != '$' {
+		p.minor = sbytes[2]
+		n++
+	}
+	return n, nil
+}
+
+// sbytes should begin where decodeVersion left off.
+func (p *hashed) decodeCost(sbytes []byte) (int, error) {
+	cost, err := strconv.Atoi(string(sbytes[0:2]))
+	if err != nil {
+		return -1, err
+	}
+	err = checkCost(cost)
+	if err != nil {
+		return -1, err
+	}
+	p.cost = cost
+	return 3, nil
+}
+
+func (p *hashed) String() string {
+	return fmt.Sprintf("&{hash: %#v, salt: %#v, cost: %d, major: %c, minor: %c}", string(p.hash), p.salt, p.cost, p.major, p.minor)
+}
+
+func checkCost(cost int) error {
+	if cost < MinCost || cost > MaxCost {
+		return InvalidCostError(cost)
+	}
+	return nil
+}

vendor/golang.org/x/crypto/blowfish/block.go

@@ -0,0 +1,159 @@
+// Copyright 2010 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 blowfish
+
+// getNextWord returns the next big-endian uint32 value from the byte slice
+// at the given position in a circular manner, updating the position.
+func getNextWord(b []byte, pos *int) uint32 {
+	var w uint32
+	j := *pos
+	for i := 0; i < 4; i++ {
+		w = w<<8 | uint32(b[j])
+		j++
+		if j >= len(b) {
+			j = 0
+		}
+	}
+	*pos = j
+	return w
+}
+
+// ExpandKey performs a key expansion on the given *Cipher. Specifically, it
+// performs the Blowfish algorithm's key schedule which sets up the *Cipher's
+// pi and substitution tables for calls to Encrypt. This is used, primarily,
+// by the bcrypt package to reuse the Blowfish key schedule during its
+// set up. It's unlikely that you need to use this directly.
+func ExpandKey(key []byte, c *Cipher) {
+	j := 0
+	for i := 0; i < 18; i++ {
+		// Using inlined getNextWord for performance.
+		var d uint32
+		for k := 0; k < 4; k++ {
+			d = d<<8 | uint32(key[j])
+			j++
+			if j >= len(key) {
+				j = 0
+			}
+		}
+		c.p[i] ^= d
+	}
+
+	var l, r uint32
+	for i := 0; i < 18; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.p[i], c.p[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.s0[i], c.s0[i+1] = l, r
+	}
+	for i := 0; i < 256; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.s1[i], c.s1[i+1] = l, r
+	}
+	for i := 0; i < 256; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.s2[i], c.s2[i+1] = l, r
+	}
+	for i := 0; i < 256; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.s3[i], c.s3[i+1] = l, r
+	}
+}
+
+// This is similar to ExpandKey, but folds the salt during the key
+// schedule. While ExpandKey is essentially expandKeyWithSalt with an all-zero
+// salt passed in, reusing ExpandKey turns out to be a place of inefficiency
+// and specializing it here is useful.
+func expandKeyWithSalt(key []byte, salt []byte, c *Cipher) {
+	j := 0
+	for i := 0; i < 18; i++ {
+		c.p[i] ^= getNextWord(key, &j)
+	}
+
+	j = 0
+	var l, r uint32
+	for i := 0; i < 18; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.p[i], c.p[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.s0[i], c.s0[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.s1[i], c.s1[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.s2[i], c.s2[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.s3[i], c.s3[i+1] = l, r
+	}
+}
+
+func encryptBlock(l, r uint32, c *Cipher) (uint32, uint32) {
+	xl, xr := l, r
+	xl ^= c.p[0]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[1]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[2]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[3]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[4]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[5]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[6]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[7]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[8]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[9]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[10]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[11]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[12]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[13]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[14]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[15]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[16]
+	xr ^= c.p[17]
+	return xr, xl
+}
+
+func decryptBlock(l, r uint32, c *Cipher) (uint32, uint32) {
+	xl, xr := l, r
+	xl ^= c.p[17]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[16]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[15]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[14]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[13]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[12]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[11]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[10]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[9]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[8]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[7]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[6]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[5]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[4]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[3]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[2]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[1]
+	xr ^= c.p[0]
+	return xr, xl
+}

vendor/golang.org/x/crypto/blowfish/cipher.go

@@ -0,0 +1,99 @@
+// Copyright 2010 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 blowfish implements Bruce Schneier's Blowfish encryption algorithm.
+//
+// Blowfish is a legacy cipher and its short block size makes it vulnerable to
+// birthday bound attacks (see https://sweet32.info). It should only be used
+// where compatibility with legacy systems, not security, is the goal.
+//
+// Deprecated: any new system should use AES (from crypto/aes, if necessary in
+// an AEAD mode like crypto/cipher.NewGCM) or XChaCha20-Poly1305 (from
+// golang.org/x/crypto/chacha20poly1305).
+package blowfish // import "golang.org/x/crypto/blowfish"
+
+// The code is a port of Bruce Schneier's C implementation.
+// See https://www.schneier.com/blowfish.html.
+
+import "strconv"
+
+// The Blowfish block size in bytes.
+const BlockSize = 8
+
+// A Cipher is an instance of Blowfish encryption using a particular key.
+type Cipher struct {
+	p              [18]uint32
+	s0, s1, s2, s3 [256]uint32
+}
+
+type KeySizeError int
+
+func (k KeySizeError) Error() string {
+	return "crypto/blowfish: invalid key size " + strconv.Itoa(int(k))
+}
+
+// NewCipher creates and returns a Cipher.
+// The key argument should be the Blowfish key, from 1 to 56 bytes.
+func NewCipher(key []byte) (*Cipher, error) {
+	var result Cipher
+	if k := len(key); k < 1 || k > 56 {
+		return nil, KeySizeError(k)
+	}
+	initCipher(&result)
+	ExpandKey(key, &result)
+	return &result, nil
+}
+
+// NewSaltedCipher creates a returns a Cipher that folds a salt into its key
+// schedule. For most purposes, NewCipher, instead of NewSaltedCipher, is
+// sufficient and desirable. For bcrypt compatibility, the key can be over 56
+// bytes.
+func NewSaltedCipher(key, salt []byte) (*Cipher, error) {
+	if len(salt) == 0 {
+		return NewCipher(key)
+	}
+	var result Cipher
+	if k := len(key); k < 1 {
+		return nil, KeySizeError(k)
+	}
+	initCipher(&result)
+	expandKeyWithSalt(key, salt, &result)
+	return &result, nil
+}
+
+// BlockSize returns the Blowfish block size, 8 bytes.
+// It is necessary to satisfy the Block interface in the
+// package "crypto/cipher".
+func (c *Cipher) BlockSize() int { return BlockSize }
+
+// Encrypt encrypts the 8-byte buffer src using the key k
+// and stores the result in dst.
+// Note that for amounts of data larger than a block,
+// it is not safe to just call Encrypt on successive blocks;
+// instead, use an encryption mode like CBC (see crypto/cipher/cbc.go).
+func (c *Cipher) Encrypt(dst, src []byte) {
+	l := uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3])
+	r := uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7])
+	l, r = encryptBlock(l, r, c)
+	dst[0], dst[1], dst[2], dst[3] = byte(l>>24), byte(l>>16), byte(l>>8), byte(l)
+	dst[4], dst[5], dst[6], dst[7] = byte(r>>24), byte(r>>16), byte(r>>8), byte(r)
+}
+
+// Decrypt decrypts the 8-byte buffer src using the key k
+// and stores the result in dst.
+func (c *Cipher) Decrypt(dst, src []byte) {
+	l := uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3])
+	r := uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7])
+	l, r = decryptBlock(l, r, c)
+	dst[0], dst[1], dst[2], dst[3] = byte(l>>24), byte(l>>16), byte(l>>8), byte(l)
+	dst[4], dst[5], dst[6], dst[7] = byte(r>>24), byte(r>>16), byte(r>>8), byte(r)
+}
+
+func initCipher(c *Cipher) {
+	copy(c.p[0:], p[0:])
+	copy(c.s0[0:], s0[0:])
+	copy(c.s1[0:], s1[0:])
+	copy(c.s2[0:], s2[0:])
+	copy(c.s3[0:], s3[0:])
+}

vendor/golang.org/x/crypto/blowfish/const.go

@@ -0,0 +1,199 @@
+// Copyright 2010 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.
+
+// The startup permutation array and substitution boxes.
+// They are the hexadecimal digits of PI; see:
+// https://www.schneier.com/code/constants.txt.
+
+package blowfish
+
+var s0 = [256]uint32{
+	0xd1310ba6, 0x98dfb5ac, 0x2ffd72db, 0xd01adfb7, 0xb8e1afed, 0x6a267e96,
+	0xba7c9045, 0xf12c7f99, 0x24a19947, 0xb3916cf7, 0x0801f2e2, 0x858efc16,
+	0x636920d8, 0x71574e69, 0xa458fea3, 0xf4933d7e, 0x0d95748f, 0x728eb658,
+	0x718bcd58, 0x82154aee, 0x7b54a41d, 0xc25a59b5, 0x9c30d539, 0x2af26013,
+	0xc5d1b023, 0x286085f0, 0xca417918, 0xb8db38ef, 0x8e79dcb0, 0x603a180e,
+	0x6c9e0e8b, 0xb01e8a3e, 0xd71577c1, 0xbd314b27, 0x78af2fda, 0x55605c60,
+	0xe65525f3, 0xaa55ab94, 0x57489862, 0x63e81440, 0x55ca396a, 0x2aab10b6,
+	0xb4cc5c34, 0x1141e8ce, 0xa15486af, 0x7c72e993, 0xb3ee1411, 0x636fbc2a,
+	0x2ba9c55d, 0x741831f6, 0xce5c3e16, 0x9b87931e, 0xafd6ba33, 0x6c24cf5c,
+	0x7a325381, 0x28958677, 0x3b8f4898, 0x6b4bb9af, 0xc4bfe81b, 0x66282193,
+	0x61d809cc, 0xfb21a991, 0x487cac60, 0x5dec8032, 0xef845d5d, 0xe98575b1,
+	0xdc262302, 0xeb651b88, 0x23893e81, 0xd396acc5, 0x0f6d6ff3, 0x83f44239,
+	0x2e0b4482, 0xa4842004, 0x69c8f04a, 0x9e1f9b5e, 0x21c66842, 0xf6e96c9a,
+	0x670c9c61, 0xabd388f0, 0x6a51a0d2, 0xd8542f68, 0x960fa728, 0xab5133a3,
+	0x6eef0b6c, 0x137a3be4, 0xba3bf050, 0x7efb2a98, 0xa1f1651d, 0x39af0176,
+	0x66ca593e, 0x82430e88, 0x8cee8619, 0x456f9fb4, 0x7d84a5c3, 0x3b8b5ebe,
+	0xe06f75d8, 0x85c12073, 0x401a449f, 0x56c16aa6, 0x4ed3aa62, 0x363f7706,
+	0x1bfedf72, 0x429b023d, 0x37d0d724, 0xd00a1248, 0xdb0fead3, 0x49f1c09b,
+	0x075372c9, 0x80991b7b, 0x25d479d8, 0xf6e8def7, 0xe3fe501a, 0xb6794c3b,
+	0x976ce0bd, 0x04c006ba, 0xc1a94fb6, 0x409f60c4, 0x5e5c9ec2, 0x196a2463,
+	0x68fb6faf, 0x3e6c53b5, 0x1339b2eb, 0x3b52ec6f, 0x6dfc511f, 0x9b30952c,
+	0xcc814544, 0xaf5ebd09, 0xbee3d004, 0xde334afd, 0x660f2807, 0x192e4bb3,
+	0xc0cba857, 0x45c8740f, 0xd20b5f39, 0xb9d3fbdb, 0x5579c0bd, 0x1a60320a,
+	0xd6a100c6, 0x402c7279, 0x679f25fe, 0xfb1fa3cc, 0x8ea5e9f8, 0xdb3222f8,
+	0x3c7516df, 0xfd616b15, 0x2f501ec8, 0xad0552ab, 0x323db5fa, 0xfd238760,
+	0x53317b48, 0x3e00df82, 0x9e5c57bb, 0xca6f8ca0, 0x1a87562e, 0xdf1769db,
+	0xd542a8f6, 0x287effc3, 0xac6732c6, 0x8c4f5573, 0x695b27b0, 0xbbca58c8,
+	0xe1ffa35d, 0xb8f011a0, 0x10fa3d98, 0xfd2183b8, 0x4afcb56c, 0x2dd1d35b,
+	0x9a53e479, 0xb6f84565, 0xd28e49bc, 0x4bfb9790, 0xe1ddf2da, 0xa4cb7e33,
+	0x62fb1341, 0xcee4c6e8, 0xef20cada, 0x36774c01, 0xd07e9efe, 0x2bf11fb4,
+	0x95dbda4d, 0xae909198, 0xeaad8e71, 0x6b93d5a0, 0xd08ed1d0, 0xafc725e0,
+	0x8e3c5b2f, 0x8e7594b7, 0x8ff6e2fb, 0xf2122b64, 0x8888b812, 0x900df01c,
+	0x4fad5ea0, 0x688fc31c, 0xd1cff191, 0xb3a8c1ad, 0x2f2f2218, 0xbe0e1777,
+	0xea752dfe, 0x8b021fa1, 0xe5a0cc0f, 0xb56f74e8, 0x18acf3d6, 0xce89e299,
+	0xb4a84fe0, 0xfd13e0b7, 0x7cc43b81, 0xd2ada8d9, 0x165fa266, 0x80957705,
+	0x93cc7314, 0x211a1477, 0xe6ad2065, 0x77b5fa86, 0xc75442f5, 0xfb9d35cf,
+	0xebcdaf0c, 0x7b3e89a0, 0xd6411bd3, 0xae1e7e49, 0x00250e2d, 0x2071b35e,
+	0x226800bb, 0x57b8e0af, 0x2464369b, 0xf009b91e, 0x5563911d, 0x59dfa6aa,
+	0x78c14389, 0xd95a537f, 0x207d5ba2, 0x02e5b9c5, 0x83260376, 0x6295cfa9,
+	0x11c81968, 0x4e734a41, 0xb3472dca, 0x7b14a94a, 0x1b510052, 0x9a532915,
+	0xd60f573f, 0xbc9bc6e4, 0x2b60a476, 0x81e67400, 0x08ba6fb5, 0x571be91f,
+	0xf296ec6b, 0x2a0dd915, 0xb6636521, 0xe7b9f9b6, 0xff34052e, 0xc5855664,
+	0x53b02d5d, 0xa99f8fa1, 0x08ba4799, 0x6e85076a,
+}
+
+var s1 = [256]uint32{
+	0x4b7a70e9, 0xb5b32944, 0xdb75092e, 0xc4192623, 0xad6ea6b0, 0x49a7df7d,
+	0x9cee60b8, 0x8fedb266, 0xecaa8c71, 0x699a17ff, 0x5664526c, 0xc2b19ee1,
+	0x193602a5, 0x75094c29, 0xa0591340, 0xe4183a3e, 0x3f54989a, 0x5b429d65,
+	0x6b8fe4d6, 0x99f73fd6, 0xa1d29c07, 0xefe830f5, 0x4d2d38e6, 0xf0255dc1,
+	0x4cdd2086, 0x8470eb26, 0x6382e9c6, 0x021ecc5e, 0x09686b3f, 0x3ebaefc9,
+	0x3c971814, 0x6b6a70a1, 0x687f3584, 0x52a0e286, 0xb79c5305, 0xaa500737,
+	0x3e07841c, 0x7fdeae5c, 0x8e7d44ec, 0x5716f2b8, 0xb03ada37, 0xf0500c0d,
+	0xf01c1f04, 0x0200b3ff, 0xae0cf51a, 0x3cb574b2, 0x25837a58, 0xdc0921bd,
+	0xd19113f9, 0x7ca92ff6, 0x94324773, 0x22f54701, 0x3ae5e581, 0x37c2dadc,
+	0xc8b57634, 0x9af3dda7, 0xa9446146, 0x0fd0030e, 0xecc8c73e, 0xa4751e41,
+	0xe238cd99, 0x3bea0e2f, 0x3280bba1, 0x183eb331, 0x4e548b38, 0x4f6db908,
+	0x6f420d03, 0xf60a04bf, 0x2cb81290, 0x24977c79, 0x5679b072, 0xbcaf89af,
+	0xde9a771f, 0xd9930810, 0xb38bae12, 0xdccf3f2e, 0x5512721f, 0x2e6b7124,
+	0x501adde6, 0x9f84cd87, 0x7a584718, 0x7408da17, 0xbc9f9abc, 0xe94b7d8c,
+	0xec7aec3a, 0xdb851dfa, 0x63094366, 0xc464c3d2, 0xef1c1847, 0x3215d908,
+	0xdd433b37, 0x24c2ba16, 0x12a14d43, 0x2a65c451, 0x50940002, 0x133ae4dd,
+	0x71dff89e, 0x10314e55, 0x81ac77d6, 0x5f11199b, 0x043556f1, 0xd7a3c76b,
+	0x3c11183b, 0x5924a509, 0xf28fe6ed, 0x97f1fbfa, 0x9ebabf2c, 0x1e153c6e,
+	0x86e34570, 0xeae96fb1, 0x860e5e0a, 0x5a3e2ab3, 0x771fe71c, 0x4e3d06fa,
+	0x2965dcb9, 0x99e71d0f, 0x803e89d6, 0x5266c825, 0x2e4cc978, 0x9c10b36a,
+	0xc6150eba, 0x94e2ea78, 0xa5fc3c53, 0x1e0a2df4, 0xf2f74ea7, 0x361d2b3d,
+	0x1939260f, 0x19c27960, 0x5223a708, 0xf71312b6, 0xebadfe6e, 0xeac31f66,
+	0xe3bc4595, 0xa67bc883, 0xb17f37d1, 0x018cff28, 0xc332ddef, 0xbe6c5aa5,
+	0x65582185, 0x68ab9802, 0xeecea50f, 0xdb2f953b, 0x2aef7dad, 0x5b6e2f84,
+	0x1521b628, 0x29076170, 0xecdd4775, 0x619f1510, 0x13cca830, 0xeb61bd96,
+	0x0334fe1e, 0xaa0363cf, 0xb5735c90, 0x4c70a239, 0xd59e9e0b, 0xcbaade14,
+	0xeecc86bc, 0x60622ca7, 0x9cab5cab, 0xb2f3846e, 0x648b1eaf, 0x19bdf0ca,
+	0xa02369b9, 0x655abb50, 0x40685a32, 0x3c2ab4b3, 0x319ee9d5, 0xc021b8f7,
+	0x9b540b19, 0x875fa099, 0x95f7997e, 0x623d7da8, 0xf837889a, 0x97e32d77,
+	0x11ed935f, 0x16681281, 0x0e358829, 0xc7e61fd6, 0x96dedfa1, 0x7858ba99,
+	0x57f584a5, 0x1b227263, 0x9b83c3ff, 0x1ac24696, 0xcdb30aeb, 0x532e3054,
+	0x8fd948e4, 0x6dbc3128, 0x58ebf2ef, 0x34c6ffea, 0xfe28ed61, 0xee7c3c73,
+	0x5d4a14d9, 0xe864b7e3, 0x42105d14, 0x203e13e0, 0x45eee2b6, 0xa3aaabea,
+	0xdb6c4f15, 0xfacb4fd0, 0xc742f442, 0xef6abbb5, 0x654f3b1d, 0x41cd2105,
+	0xd81e799e, 0x86854dc7, 0xe44b476a, 0x3d816250, 0xcf62a1f2, 0x5b8d2646,
+	0xfc8883a0, 0xc1c7b6a3, 0x7f1524c3, 0x69cb7492, 0x47848a0b, 0x5692b285,
+	0x095bbf00, 0xad19489d, 0x1462b174, 0x23820e00, 0x58428d2a, 0x0c55f5ea,
+	0x1dadf43e, 0x233f7061, 0x3372f092, 0x8d937e41, 0xd65fecf1, 0x6c223bdb,
+	0x7cde3759, 0xcbee7460, 0x4085f2a7, 0xce77326e, 0xa6078084, 0x19f8509e,
+	0xe8efd855, 0x61d99735, 0xa969a7aa, 0xc50c06c2, 0x5a04abfc, 0x800bcadc,
+	0x9e447a2e, 0xc3453484, 0xfdd56705, 0x0e1e9ec9, 0xdb73dbd3, 0x105588cd,
+	0x675fda79, 0xe3674340, 0xc5c43465, 0x713e38d8, 0x3d28f89e, 0xf16dff20,
+	0x153e21e7, 0x8fb03d4a, 0xe6e39f2b, 0xdb83adf7,
+}
+
+var s2 = [256]uint32{
+	0xe93d5a68, 0x948140f7, 0xf64c261c, 0x94692934, 0x411520f7, 0x7602d4f7,
+	0xbcf46b2e, 0xd4a20068, 0xd4082471, 0x3320f46a, 0x43b7d4b7, 0x500061af,
+	0x1e39f62e, 0x97244546, 0x14214f74, 0xbf8b8840, 0x4d95fc1d, 0x96b591af,
+	0x70f4ddd3, 0x66a02f45, 0xbfbc09ec, 0x03bd9785, 0x7fac6dd0, 0x31cb8504,
+	0x96eb27b3, 0x55fd3941, 0xda2547e6, 0xabca0a9a, 0x28507825, 0x530429f4,
+	0x0a2c86da, 0xe9b66dfb, 0x68dc1462, 0xd7486900, 0x680ec0a4, 0x27a18dee,
+	0x4f3ffea2, 0xe887ad8c, 0xb58ce006, 0x7af4d6b6, 0xaace1e7c, 0xd3375fec,
+	0xce78a399, 0x406b2a42, 0x20fe9e35, 0xd9f385b9, 0xee39d7ab, 0x3b124e8b,
+	0x1dc9faf7, 0x4b6d1856, 0x26a36631, 0xeae397b2, 0x3a6efa74, 0xdd5b4332,
+	0x6841e7f7, 0xca7820fb, 0xfb0af54e, 0xd8feb397, 0x454056ac, 0xba489527,
+	0x55533a3a, 0x20838d87, 0xfe6ba9b7, 0xd096954b, 0x55a867bc, 0xa1159a58,
+	0xcca92963, 0x99e1db33, 0xa62a4a56, 0x3f3125f9, 0x5ef47e1c, 0x9029317c,
+	0xfdf8e802, 0x04272f70, 0x80bb155c, 0x05282ce3, 0x95c11548, 0xe4c66d22,
+	0x48c1133f, 0xc70f86dc, 0x07f9c9ee, 0x41041f0f, 0x404779a4, 0x5d886e17,
+	0x325f51eb, 0xd59bc0d1, 0xf2bcc18f, 0x41113564, 0x257b7834, 0x602a9c60,
+	0xdff8e8a3, 0x1f636c1b, 0x0e12b4c2, 0x02e1329e, 0xaf664fd1, 0xcad18115,
+	0x6b2395e0, 0x333e92e1, 0x3b240b62, 0xeebeb922, 0x85b2a20e, 0xe6ba0d99,
+	0xde720c8c, 0x2da2f728, 0xd0127845, 0x95b794fd, 0x647d0862, 0xe7ccf5f0,
+	0x5449a36f, 0x877d48fa, 0xc39dfd27, 0xf33e8d1e, 0x0a476341, 0x992eff74,
+	0x3a6f6eab, 0xf4f8fd37, 0xa812dc60, 0xa1ebddf8, 0x991be14c, 0xdb6e6b0d,
+	0xc67b5510, 0x6d672c37, 0x2765d43b, 0xdcd0e804, 0xf1290dc7, 0xcc00ffa3,
+	0xb5390f92, 0x690fed0b, 0x667b9ffb, 0xcedb7d9c, 0xa091cf0b, 0xd9155ea3,
+	0xbb132f88, 0x515bad24, 0x7b9479bf, 0x763bd6eb, 0x37392eb3, 0xcc115979,
+	0x8026e297, 0xf42e312d, 0x6842ada7, 0xc66a2b3b, 0x12754ccc, 0x782ef11c,
+	0x6a124237, 0xb79251e7, 0x06a1bbe6, 0x4bfb6350, 0x1a6b1018, 0x11caedfa,
+	0x3d25bdd8, 0xe2e1c3c9, 0x44421659, 0x0a121386, 0xd90cec6e, 0xd5abea2a,
+	0x64af674e, 0xda86a85f, 0xbebfe988, 0x64e4c3fe, 0x9dbc8057, 0xf0f7c086,
+	0x60787bf8, 0x6003604d, 0xd1fd8346, 0xf6381fb0, 0x7745ae04, 0xd736fccc,
+	0x83426b33, 0xf01eab71, 0xb0804187, 0x3c005e5f, 0x77a057be, 0xbde8ae24,
+	0x55464299, 0xbf582e61, 0x4e58f48f, 0xf2ddfda2, 0xf474ef38, 0x8789bdc2,
+	0x5366f9c3, 0xc8b38e74, 0xb475f255, 0x46fcd9b9, 0x7aeb2661, 0x8b1ddf84,
+	0x846a0e79, 0x915f95e2, 0x466e598e, 0x20b45770, 0x8cd55591, 0xc902de4c,
+	0xb90bace1, 0xbb8205d0, 0x11a86248, 0x7574a99e, 0xb77f19b6, 0xe0a9dc09,
+	0x662d09a1, 0xc4324633, 0xe85a1f02, 0x09f0be8c, 0x4a99a025, 0x1d6efe10,
+	0x1ab93d1d, 0x0ba5a4df, 0xa186f20f, 0x2868f169, 0xdcb7da83, 0x573906fe,
+	0xa1e2ce9b, 0x4fcd7f52, 0x50115e01, 0xa70683fa, 0xa002b5c4, 0x0de6d027,
+	0x9af88c27, 0x773f8641, 0xc3604c06, 0x61a806b5, 0xf0177a28, 0xc0f586e0,
+	0x006058aa, 0x30dc7d62, 0x11e69ed7, 0x2338ea63, 0x53c2dd94, 0xc2c21634,
+	0xbbcbee56, 0x90bcb6de, 0xebfc7da1, 0xce591d76, 0x6f05e409, 0x4b7c0188,
+	0x39720a3d, 0x7c927c24, 0x86e3725f, 0x724d9db9, 0x1ac15bb4, 0xd39eb8fc,
+	0xed545578, 0x08fca5b5, 0xd83d7cd3, 0x4dad0fc4, 0x1e50ef5e, 0xb161e6f8,
+	0xa28514d9, 0x6c51133c, 0x6fd5c7e7, 0x56e14ec4, 0x362abfce, 0xddc6c837,
+	0xd79a3234, 0x92638212, 0x670efa8e, 0x406000e0,
+}
+
+var s3 = [256]uint32{
+	0x3a39ce37, 0xd3faf5cf, 0xabc27737, 0x5ac52d1b, 0x5cb0679e, 0x4fa33742,
+	0xd3822740, 0x99bc9bbe, 0xd5118e9d, 0xbf0f7315, 0xd62d1c7e, 0xc700c47b,
+	0xb78c1b6b, 0x21a19045, 0xb26eb1be, 0x6a366eb4, 0x5748ab2f, 0xbc946e79,
+	0xc6a376d2, 0x6549c2c8, 0x530ff8ee, 0x468dde7d, 0xd5730a1d, 0x4cd04dc6,
+	0x2939bbdb, 0xa9ba4650, 0xac9526e8, 0xbe5ee304, 0xa1fad5f0, 0x6a2d519a,
+	0x63ef8ce2, 0x9a86ee22, 0xc089c2b8, 0x43242ef6, 0xa51e03aa, 0x9cf2d0a4,
+	0x83c061ba, 0x9be96a4d, 0x8fe51550, 0xba645bd6, 0x2826a2f9, 0xa73a3ae1,
+	0x4ba99586, 0xef5562e9, 0xc72fefd3, 0xf752f7da, 0x3f046f69, 0x77fa0a59,
+	0x80e4a915, 0x87b08601, 0x9b09e6ad, 0x3b3ee593, 0xe990fd5a, 0x9e34d797,
+	0x2cf0b7d9, 0x022b8b51, 0x96d5ac3a, 0x017da67d, 0xd1cf3ed6, 0x7c7d2d28,
+	0x1f9f25cf, 0xadf2b89b, 0x5ad6b472, 0x5a88f54c, 0xe029ac71, 0xe019a5e6,
+	0x47b0acfd, 0xed93fa9b, 0xe8d3c48d, 0x283b57cc, 0xf8d56629, 0x79132e28,
+	0x785f0191, 0xed756055, 0xf7960e44, 0xe3d35e8c, 0x15056dd4, 0x88f46dba,
+	0x03a16125, 0x0564f0bd, 0xc3eb9e15, 0x3c9057a2, 0x97271aec, 0xa93a072a,
+	0x1b3f6d9b, 0x1e6321f5, 0xf59c66fb, 0x26dcf319, 0x7533d928, 0xb155fdf5,
+	0x03563482, 0x8aba3cbb, 0x28517711, 0xc20ad9f8, 0xabcc5167, 0xccad925f,
+	0x4de81751, 0x3830dc8e, 0x379d5862, 0x9320f991, 0xea7a90c2, 0xfb3e7bce,
+	0x5121ce64, 0x774fbe32, 0xa8b6e37e, 0xc3293d46, 0x48de5369, 0x6413e680,
+	0xa2ae0810, 0xdd6db224, 0x69852dfd, 0x09072166, 0xb39a460a, 0x6445c0dd,
+	0x586cdecf, 0x1c20c8ae, 0x5bbef7dd, 0x1b588d40, 0xccd2017f, 0x6bb4e3bb,
+	0xdda26a7e, 0x3a59ff45, 0x3e350a44, 0xbcb4cdd5, 0x72eacea8, 0xfa6484bb,
+	0x8d6612ae, 0xbf3c6f47, 0xd29be463, 0x542f5d9e, 0xaec2771b, 0xf64e6370,
+	0x740e0d8d, 0xe75b1357, 0xf8721671, 0xaf537d5d, 0x4040cb08, 0x4eb4e2cc,
+	0x34d2466a, 0x0115af84, 0xe1b00428, 0x95983a1d, 0x06b89fb4, 0xce6ea048,
+	0x6f3f3b82, 0x3520ab82, 0x011a1d4b, 0x277227f8, 0x611560b1, 0xe7933fdc,
+	0xbb3a792b, 0x344525bd, 0xa08839e1, 0x51ce794b, 0x2f32c9b7, 0xa01fbac9,
+	0xe01cc87e, 0xbcc7d1f6, 0xcf0111c3, 0xa1e8aac7, 0x1a908749, 0xd44fbd9a,
+	0xd0dadecb, 0xd50ada38, 0x0339c32a, 0xc6913667, 0x8df9317c, 0xe0b12b4f,
+	0xf79e59b7, 0x43f5bb3a, 0xf2d519ff, 0x27d9459c, 0xbf97222c, 0x15e6fc2a,
+	0x0f91fc71, 0x9b941525, 0xfae59361, 0xceb69ceb, 0xc2a86459, 0x12baa8d1,
+	0xb6c1075e, 0xe3056a0c, 0x10d25065, 0xcb03a442, 0xe0ec6e0e, 0x1698db3b,
+	0x4c98a0be, 0x3278e964, 0x9f1f9532, 0xe0d392df, 0xd3a0342b, 0x8971f21e,
+	0x1b0a7441, 0x4ba3348c, 0xc5be7120, 0xc37632d8, 0xdf359f8d, 0x9b992f2e,
+	0xe60b6f47, 0x0fe3f11d, 0xe54cda54, 0x1edad891, 0xce6279cf, 0xcd3e7e6f,
+	0x1618b166, 0xfd2c1d05, 0x848fd2c5, 0xf6fb2299, 0xf523f357, 0xa6327623,
+	0x93a83531, 0x56cccd02, 0xacf08162, 0x5a75ebb5, 0x6e163697, 0x88d273cc,
+	0xde966292, 0x81b949d0, 0x4c50901b, 0x71c65614, 0xe6c6c7bd, 0x327a140a,
+	0x45e1d006, 0xc3f27b9a, 0xc9aa53fd, 0x62a80f00, 0xbb25bfe2, 0x35bdd2f6,
+	0x71126905, 0xb2040222, 0xb6cbcf7c, 0xcd769c2b, 0x53113ec0, 0x1640e3d3,
+	0x38abbd60, 0x2547adf0, 0xba38209c, 0xf746ce76, 0x77afa1c5, 0x20756060,
+	0x85cbfe4e, 0x8ae88dd8, 0x7aaaf9b0, 0x4cf9aa7e, 0x1948c25c, 0x02fb8a8c,
+	0x01c36ae4, 0xd6ebe1f9, 0x90d4f869, 0xa65cdea0, 0x3f09252d, 0xc208e69f,
+	0xb74e6132, 0xce77e25b, 0x578fdfe3, 0x3ac372e6,
+}
+
+var p = [18]uint32{
+	0x243f6a88, 0x85a308d3, 0x13198a2e, 0x03707344, 0xa4093822, 0x299f31d0,
+	0x082efa98, 0xec4e6c89, 0x452821e6, 0x38d01377, 0xbe5466cf, 0x34e90c6c,
+	0xc0ac29b7, 0xc97c50dd, 0x3f84d5b5, 0xb5470917, 0x9216d5d9, 0x8979fb1b,
+}

vendor/golang.org/x/crypto/ssh/terminal/terminal.go

@@ -0,0 +1,76 @@
+// Copyright 2011 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 terminal provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Deprecated: this package moved to golang.org/x/term.
+package terminal
+
+import (
+	"io"
+
+	"golang.org/x/term"
+)
+
+// EscapeCodes contains escape sequences that can be written to the terminal in
+// order to achieve different styles of text.
+type EscapeCodes = term.EscapeCodes
+
+// Terminal contains the state for running a VT100 terminal that is capable of
+// reading lines of input.
+type Terminal = term.Terminal
+
+// NewTerminal runs a VT100 terminal on the given ReadWriter. If the ReadWriter is
+// a local terminal, that terminal must first have been put into raw mode.
+// prompt is a string that is written at the start of each input line (i.e.
+// "> ").
+func NewTerminal(c io.ReadWriter, prompt string) *Terminal {
+	return term.NewTerminal(c, prompt)
+}
+
+// ErrPasteIndicator may be returned from ReadLine as the error, in addition
+// to valid line data. It indicates that bracketed paste mode is enabled and
+// that the returned line consists only of pasted data. Programs may wish to
+// interpret pasted data more literally than typed data.
+var ErrPasteIndicator = term.ErrPasteIndicator
+
+// State contains the state of a terminal.
+type State = term.State
+
+// IsTerminal returns whether the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	return term.IsTerminal(fd)
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	return term.ReadPassword(fd)
+}
+
+// MakeRaw puts the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	return term.MakeRaw(fd)
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, oldState *State) error {
+	return term.Restore(fd, oldState)
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	return term.GetState(fd)
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	return term.GetSize(fd)
+}

vendor/vendor.json

@@ -1430,38 +1430,34 @@
 			"revisionTime": "2020-12-30T03:08:14Z"
 		},
 		{
-			"checksumSHA1": "CSMVjFF7FnylAUUKW1e/4r+VFXA=",
-			"origin": "github.com/kataras/iris/vendor/golang.org/x/crypto/acme",
+			"checksumSHA1": "VtHVTGvqt06GXQ20F/6CZEhlWSQ=",
 			"path": "golang.org/x/crypto/acme",
-			"revision": "b1670413ba6a7532e46c12ff23d0914c270d2768",
-			"revisionTime": "2018-09-01T16:27:21Z"
+			"revision": "eec23a3978adcfd26c29f4153eaa3e3d9b2cc53a",
+			"revisionTime": "2020-12-21T16:57:36Z"
 		},
 		{
-			"checksumSHA1": "lBWiVnI+9tnYWuXnUiWljDy9dnc=",
-			"origin": "github.com/kataras/iris/vendor/golang.org/x/crypto/acme/autocert",
+			"checksumSHA1": "aDAIGbVOJXGY6JQPvi+6jPFhejk=",
 			"path": "golang.org/x/crypto/acme/autocert",
-			"revision": "b1670413ba6a7532e46c12ff23d0914c270d2768",
-			"revisionTime": "2018-09-01T16:27:21Z"
+			"revision": "eec23a3978adcfd26c29f4153eaa3e3d9b2cc53a",
+			"revisionTime": "2020-12-21T16:57:36Z"
 		},
 		{
 			"checksumSHA1": "oCH3J96RWvO8W4xjix47PModpio=",
-			"origin": "github.com/xyproto/permissionsql/vendor/golang.org/x/crypto/bcrypt",
 			"path": "golang.org/x/crypto/bcrypt",
-			"revision": "62470623e918daac94059ecb16bd618df997f9cf",
-			"revisionTime": "2018-12-11T08:48:59Z"
+			"revision": "eec23a3978adcfd26c29f4153eaa3e3d9b2cc53a",
+			"revisionTime": "2020-12-21T16:57:36Z"
 		},
 		{
-			"checksumSHA1": "oVPHWesOmZ02vLq2fglGvf+AMgk=",
-			"origin": "github.com/xyproto/permissionsql/vendor/golang.org/x/crypto/blowfish",
+			"checksumSHA1": "q+XI9g44wd9mYvf3S5Wo8YZjAus=",
 			"path": "golang.org/x/crypto/blowfish",
-			"revision": "62470623e918daac94059ecb16bd618df997f9cf",
-			"revisionTime": "2018-12-11T08:48:59Z"
+			"revision": "eec23a3978adcfd26c29f4153eaa3e3d9b2cc53a",
+			"revisionTime": "2020-12-21T16:57:36Z"
 		},
 		{
-			"checksumSHA1": "BGm8lKZmvJbf/YOJLeL1rw2WVjA=",
+			"checksumSHA1": "duEcJaULRzejc7AXv+Etpn/Q/BU=",
 			"path": "golang.org/x/crypto/ssh/terminal",
-			"revision": "7f39a6fea4fe9364fb61e1def6a268a51b4f3a06",
-			"revisionTime": "2018-06-15T16:03:23Z"
+			"revision": "eec23a3978adcfd26c29f4153eaa3e3d9b2cc53a",
+			"revisionTime": "2020-12-21T16:57:36Z"
 		},
 		{
 			"checksumSHA1": "NjyXtXsaf0ulRJn6HQSP1FqGL4A=",