Vendor main dependencies.

vendor/github.com/xenolf/lego/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Sebastian Erhart
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/github.com/xenolf/lego/account.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"crypto"
+	"encoding/json"
+	"io/ioutil"
+	"os"
+	"path"
+
+	"github.com/xenolf/lego/acme"
+)
+
+// Account represents a users local saved credentials
+type Account struct {
+	Email        string `json:"email"`
+	key          crypto.PrivateKey
+	Registration *acme.RegistrationResource `json:"registration"`
+
+	conf *Configuration
+}
+
+// NewAccount creates a new account for an email address
+func NewAccount(email string, conf *Configuration) *Account {
+	accKeysPath := conf.AccountKeysPath(email)
+	// TODO: move to function in configuration?
+	accKeyPath := accKeysPath + string(os.PathSeparator) + email + ".key"
+	if err := checkFolder(accKeysPath); err != nil {
+		logger().Fatalf("Could not check/create directory for account %s: %v", email, err)
+	}
+
+	var privKey crypto.PrivateKey
+	if _, err := os.Stat(accKeyPath); os.IsNotExist(err) {
+
+		logger().Printf("No key found for account %s. Generating a curve P384 EC key.", email)
+		privKey, err = generatePrivateKey(accKeyPath)
+		if err != nil {
+			logger().Fatalf("Could not generate RSA private account key for account %s: %v", email, err)
+		}
+
+		logger().Printf("Saved key to %s", accKeyPath)
+	} else {
+		privKey, err = loadPrivateKey(accKeyPath)
+		if err != nil {
+			logger().Fatalf("Could not load RSA private key from file %s: %v", accKeyPath, err)
+		}
+	}
+
+	accountFile := path.Join(conf.AccountPath(email), "account.json")
+	if _, err := os.Stat(accountFile); os.IsNotExist(err) {
+		return &Account{Email: email, key: privKey, conf: conf}
+	}
+
+	fileBytes, err := ioutil.ReadFile(accountFile)
+	if err != nil {
+		logger().Fatalf("Could not load file for account %s -> %v", email, err)
+	}
+
+	var acc Account
+	err = json.Unmarshal(fileBytes, &acc)
+	if err != nil {
+		logger().Fatalf("Could not parse file for account %s -> %v", email, err)
+	}
+
+	acc.key = privKey
+	acc.conf = conf
+
+	if acc.Registration == nil {
+		logger().Fatalf("Could not load account for %s. Registration is nil.", email)
+	}
+
+	if acc.conf == nil {
+		logger().Fatalf("Could not load account for %s. Configuration is nil.", email)
+	}
+
+	return &acc
+}
+
+/** Implementation of the acme.User interface **/
+
+// GetEmail returns the email address for the account
+func (a *Account) GetEmail() string {
+	return a.Email
+}
+
+// GetPrivateKey returns the private RSA account key.
+func (a *Account) GetPrivateKey() crypto.PrivateKey {
+	return a.key
+}
+
+// GetRegistration returns the server registration
+func (a *Account) GetRegistration() *acme.RegistrationResource {
+	return a.Registration
+}
+
+/** End **/
+
+// Save the account to disk
+func (a *Account) Save() error {
+	jsonBytes, err := json.MarshalIndent(a, "", "\t")
+	if err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(
+		path.Join(a.conf.AccountPath(a.Email), "account.json"),
+		jsonBytes,
+		0600,
+	)
+}

vendor/github.com/xenolf/lego/acme/challenges.go

@@ -0,0 +1,16 @@
+package acme
+
+// Challenge is a string that identifies a particular type and version of ACME challenge.
+type Challenge string
+
+const (
+	// HTTP01 is the "http-01" ACME challenge https://github.com/ietf-wg-acme/acme/blob/master/draft-ietf-acme-acme.md#http
+	// Note: HTTP01ChallengePath returns the URL path to fulfill this challenge
+	HTTP01 = Challenge("http-01")
+	// TLSSNI01 is the "tls-sni-01" ACME challenge https://github.com/ietf-wg-acme/acme/blob/master/draft-ietf-acme-acme.md#tls-with-server-name-indication-tls-sni
+	// Note: TLSSNI01ChallengeCert returns a certificate to fulfill this challenge
+	TLSSNI01 = Challenge("tls-sni-01")
+	// DNS01 is the "dns-01" ACME challenge https://github.com/ietf-wg-acme/acme/blob/master/draft-ietf-acme-acme.md#dns
+	// Note: DNS01Record returns a DNS record which will fulfill this challenge
+	DNS01 = Challenge("dns-01")
+)

vendor/github.com/xenolf/lego/acme/client.go

@@ -0,0 +1,762 @@
+// Package acme implements the ACME protocol for Let's Encrypt and other conforming providers.
+package acme
+
+import (
+	"crypto"
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var (
+	// Logger is an optional custom logger.
+	Logger *log.Logger
+)
+
+// logf writes a log entry. It uses Logger if not
+// nil, otherwise it uses the default log.Logger.
+func logf(format string, args ...interface{}) {
+	if Logger != nil {
+		Logger.Printf(format, args...)
+	} else {
+		log.Printf(format, args...)
+	}
+}
+
+// User interface is to be implemented by users of this library.
+// It is used by the client type to get user specific information.
+type User interface {
+	GetEmail() string
+	GetRegistration() *RegistrationResource
+	GetPrivateKey() crypto.PrivateKey
+}
+
+// Interface for all challenge solvers to implement.
+type solver interface {
+	Solve(challenge challenge, domain string) error
+}
+
+type validateFunc func(j *jws, domain, uri string, chlng challenge) error
+
+// Client is the user-friendy way to ACME
+type Client struct {
+	directory directory
+	user      User
+	jws       *jws
+	keyType   KeyType
+	solvers   map[Challenge]solver
+}
+
+// NewClient creates a new ACME client on behalf of the user. The client will depend on
+// the ACME directory located at caDirURL for the rest of its actions.  A private
+// key of type keyType (see KeyType contants) will be generated when requesting a new
+// certificate if one isn't provided.
+func NewClient(caDirURL string, user User, keyType KeyType) (*Client, error) {
+	privKey := user.GetPrivateKey()
+	if privKey == nil {
+		return nil, errors.New("private key was nil")
+	}
+
+	var dir directory
+	if _, err := getJSON(caDirURL, &dir); err != nil {
+		return nil, fmt.Errorf("get directory at '%s': %v", caDirURL, err)
+	}
+
+	if dir.NewRegURL == "" {
+		return nil, errors.New("directory missing new registration URL")
+	}
+	if dir.NewAuthzURL == "" {
+		return nil, errors.New("directory missing new authz URL")
+	}
+	if dir.NewCertURL == "" {
+		return nil, errors.New("directory missing new certificate URL")
+	}
+	if dir.RevokeCertURL == "" {
+		return nil, errors.New("directory missing revoke certificate URL")
+	}
+
+	jws := &jws{privKey: privKey, directoryURL: caDirURL}
+
+	// REVIEW: best possibility?
+	// Add all available solvers with the right index as per ACME
+	// spec to this map. Otherwise they won`t be found.
+	solvers := make(map[Challenge]solver)
+	solvers[HTTP01] = &httpChallenge{jws: jws, validate: validate, provider: &HTTPProviderServer{}}
+	solvers[TLSSNI01] = &tlsSNIChallenge{jws: jws, validate: validate, provider: &TLSProviderServer{}}
+
+	return &Client{directory: dir, user: user, jws: jws, keyType: keyType, solvers: solvers}, nil
+}
+
+// SetChallengeProvider specifies a custom provider p that can solve the given challenge type.
+func (c *Client) SetChallengeProvider(challenge Challenge, p ChallengeProvider) error {
+	switch challenge {
+	case HTTP01:
+		c.solvers[challenge] = &httpChallenge{jws: c.jws, validate: validate, provider: p}
+	case TLSSNI01:
+		c.solvers[challenge] = &tlsSNIChallenge{jws: c.jws, validate: validate, provider: p}
+	case DNS01:
+		c.solvers[challenge] = &dnsChallenge{jws: c.jws, validate: validate, provider: p}
+	default:
+		return fmt.Errorf("Unknown challenge %v", challenge)
+	}
+	return nil
+}
+
+// SetHTTPAddress specifies a custom interface:port to be used for HTTP based challenges.
+// If this option is not used, the default port 80 and all interfaces will be used.
+// To only specify a port and no interface use the ":port" notation.
+//
+// NOTE: This REPLACES any custom HTTP provider previously set by calling
+// c.SetChallengeProvider with the default HTTP challenge provider.
+func (c *Client) SetHTTPAddress(iface string) error {
+	host, port, err := net.SplitHostPort(iface)
+	if err != nil {
+		return err
+	}
+
+	if chlng, ok := c.solvers[HTTP01]; ok {
+		chlng.(*httpChallenge).provider = NewHTTPProviderServer(host, port)
+	}
+
+	return nil
+}
+
+// SetTLSAddress specifies a custom interface:port to be used for TLS based challenges.
+// If this option is not used, the default port 443 and all interfaces will be used.
+// To only specify a port and no interface use the ":port" notation.
+//
+// NOTE: This REPLACES any custom TLS-SNI provider previously set by calling
+// c.SetChallengeProvider with the default TLS-SNI challenge provider.
+func (c *Client) SetTLSAddress(iface string) error {
+	host, port, err := net.SplitHostPort(iface)
+	if err != nil {
+		return err
+	}
+
+	if chlng, ok := c.solvers[TLSSNI01]; ok {
+		chlng.(*tlsSNIChallenge).provider = NewTLSProviderServer(host, port)
+	}
+	return nil
+}
+
+// ExcludeChallenges explicitly removes challenges from the pool for solving.
+func (c *Client) ExcludeChallenges(challenges []Challenge) {
+	// Loop through all challenges and delete the requested one if found.
+	for _, challenge := range challenges {
+		delete(c.solvers, challenge)
+	}
+}
+
+// Register the current account to the ACME server.
+func (c *Client) Register() (*RegistrationResource, error) {
+	if c == nil || c.user == nil {
+		return nil, errors.New("acme: cannot register a nil client or user")
+	}
+	logf("[INFO] acme: Registering account for %s", c.user.GetEmail())
+
+	regMsg := registrationMessage{
+		Resource: "new-reg",
+	}
+	if c.user.GetEmail() != "" {
+		regMsg.Contact = []string{"mailto:" + c.user.GetEmail()}
+	} else {
+		regMsg.Contact = []string{}
+	}
+
+	var serverReg Registration
+	var regURI string
+	hdr, err := postJSON(c.jws, c.directory.NewRegURL, regMsg, &serverReg)
+	if err != nil {
+		remoteErr, ok := err.(RemoteError)
+		if ok && remoteErr.StatusCode == 409 {
+			regURI = hdr.Get("Location")
+			regMsg = registrationMessage{
+				Resource: "reg",
+			}
+			if hdr, err = postJSON(c.jws, regURI, regMsg, &serverReg); err != nil {
+				return nil, err
+			}
+		} else {
+			return nil, err
+		}
+	}
+
+	reg := &RegistrationResource{Body: serverReg}
+
+	links := parseLinks(hdr["Link"])
+
+	if regURI == "" {
+		regURI = hdr.Get("Location")
+	}
+	reg.URI = regURI
+	if links["terms-of-service"] != "" {
+		reg.TosURL = links["terms-of-service"]
+	}
+
+	if links["next"] != "" {
+		reg.NewAuthzURL = links["next"]
+	} else {
+		return nil, errors.New("acme: The server did not return 'next' link to proceed")
+	}
+
+	return reg, nil
+}
+
+// DeleteRegistration deletes the client's user registration from the ACME
+// server.
+func (c *Client) DeleteRegistration() error {
+	if c == nil || c.user == nil {
+		return errors.New("acme: cannot unregister a nil client or user")
+	}
+	logf("[INFO] acme: Deleting account for %s", c.user.GetEmail())
+
+	regMsg := registrationMessage{
+		Resource: "reg",
+		Delete:   true,
+	}
+
+	_, err := postJSON(c.jws, c.user.GetRegistration().URI, regMsg, nil)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// QueryRegistration runs a POST request on the client's registration and
+// returns the result.
+//
+// This is similar to the Register function, but acting on an existing
+// registration link and resource.
+func (c *Client) QueryRegistration() (*RegistrationResource, error) {
+	if c == nil || c.user == nil {
+		return nil, errors.New("acme: cannot query the registration of a nil client or user")
+	}
+	// Log the URL here instead of the email as the email may not be set
+	logf("[INFO] acme: Querying account for %s", c.user.GetRegistration().URI)
+
+	regMsg := registrationMessage{
+		Resource: "reg",
+	}
+
+	var serverReg Registration
+	hdr, err := postJSON(c.jws, c.user.GetRegistration().URI, regMsg, &serverReg)
+	if err != nil {
+		return nil, err
+	}
+
+	reg := &RegistrationResource{Body: serverReg}
+
+	links := parseLinks(hdr["Link"])
+	// Location: header is not returned so this needs to be populated off of
+	// existing URI
+	reg.URI = c.user.GetRegistration().URI
+	if links["terms-of-service"] != "" {
+		reg.TosURL = links["terms-of-service"]
+	}
+
+	if links["next"] != "" {
+		reg.NewAuthzURL = links["next"]
+	} else {
+		return nil, errors.New("acme: No new-authz link in response to registration query")
+	}
+
+	return reg, nil
+}
+
+// AgreeToTOS updates the Client registration and sends the agreement to
+// the server.
+func (c *Client) AgreeToTOS() error {
+	reg := c.user.GetRegistration()
+
+	reg.Body.Agreement = c.user.GetRegistration().TosURL
+	reg.Body.Resource = "reg"
+	_, err := postJSON(c.jws, c.user.GetRegistration().URI, c.user.GetRegistration().Body, nil)
+	return err
+}
+
+// ObtainCertificateForCSR tries to obtain a certificate matching the CSR passed into it.
+// The domains are inferred from the CommonName and SubjectAltNames, if any. The private key
+// for this CSR is not required.
+// If bundle is true, the []byte contains both the issuer certificate and
+// your issued certificate as a bundle.
+// This function will never return a partial certificate. If one domain in the list fails,
+// the whole certificate will fail.
+func (c *Client) ObtainCertificateForCSR(csr x509.CertificateRequest, bundle bool) (CertificateResource, map[string]error) {
+	// figure out what domains it concerns
+	// start with the common name
+	domains := []string{csr.Subject.CommonName}
+
+	// loop over the SubjectAltName DNS names
+DNSNames:
+	for _, sanName := range csr.DNSNames {
+		for _, existingName := range domains {
+			if existingName == sanName {
+				// duplicate; skip this name
+				continue DNSNames
+			}
+		}
+
+		// name is unique
+		domains = append(domains, sanName)
+	}
+
+	if bundle {
+		logf("[INFO][%s] acme: Obtaining bundled SAN certificate given a CSR", strings.Join(domains, ", "))
+	} else {
+		logf("[INFO][%s] acme: Obtaining SAN certificate given a CSR", strings.Join(domains, ", "))
+	}
+
+	challenges, failures := c.getChallenges(domains)
+	// If any challenge fails - return. Do not generate partial SAN certificates.
+	if len(failures) > 0 {
+		return CertificateResource{}, failures
+	}
+
+	errs := c.solveChallenges(challenges)
+	// If any challenge fails - return. Do not generate partial SAN certificates.
+	if len(errs) > 0 {
+		return CertificateResource{}, errs
+	}
+
+	logf("[INFO][%s] acme: Validations succeeded; requesting certificates", strings.Join(domains, ", "))
+
+	cert, err := c.requestCertificateForCsr(challenges, bundle, csr.Raw, nil)
+	if err != nil {
+		for _, chln := range challenges {
+			failures[chln.Domain] = err
+		}
+	}
+
+	// Add the CSR to the certificate so that it can be used for renewals.
+	cert.CSR = pemEncode(&csr)
+
+	return cert, failures
+}
+
+// ObtainCertificate tries to obtain a single certificate using all domains passed into it.
+// The first domain in domains is used for the CommonName field of the certificate, all other
+// domains are added using the Subject Alternate Names extension. A new private key is generated
+// for every invocation of this function. If you do not want that you can supply your own private key
+// in the privKey parameter. If this parameter is non-nil it will be used instead of generating a new one.
+// If bundle is true, the []byte contains both the issuer certificate and
+// your issued certificate as a bundle.
+// This function will never return a partial certificate. If one domain in the list fails,
+// the whole certificate will fail.
+func (c *Client) ObtainCertificate(domains []string, bundle bool, privKey crypto.PrivateKey, mustStaple bool) (CertificateResource, map[string]error) {
+	if bundle {
+		logf("[INFO][%s] acme: Obtaining bundled SAN certificate", strings.Join(domains, ", "))
+	} else {
+		logf("[INFO][%s] acme: Obtaining SAN certificate", strings.Join(domains, ", "))
+	}
+
+	challenges, failures := c.getChallenges(domains)
+	// If any challenge fails - return. Do not generate partial SAN certificates.
+	if len(failures) > 0 {
+		return CertificateResource{}, failures
+	}
+
+	errs := c.solveChallenges(challenges)
+	// If any challenge fails - return. Do not generate partial SAN certificates.
+	if len(errs) > 0 {
+		return CertificateResource{}, errs
+	}
+
+	logf("[INFO][%s] acme: Validations succeeded; requesting certificates", strings.Join(domains, ", "))
+
+	cert, err := c.requestCertificate(challenges, bundle, privKey, mustStaple)
+	if err != nil {
+		for _, chln := range challenges {
+			failures[chln.Domain] = err
+		}
+	}
+
+	return cert, failures
+}
+
+// RevokeCertificate takes a PEM encoded certificate or bundle and tries to revoke it at the CA.
+func (c *Client) RevokeCertificate(certificate []byte) error {
+	certificates, err := parsePEMBundle(certificate)
+	if err != nil {
+		return err
+	}
+
+	x509Cert := certificates[0]
+	if x509Cert.IsCA {
+		return fmt.Errorf("Certificate bundle starts with a CA certificate")
+	}
+
+	encodedCert := base64.URLEncoding.EncodeToString(x509Cert.Raw)
+
+	_, err = postJSON(c.jws, c.directory.RevokeCertURL, revokeCertMessage{Resource: "revoke-cert", Certificate: encodedCert}, nil)
+	return err
+}
+
+// RenewCertificate takes a CertificateResource and tries to renew the certificate.
+// If the renewal process succeeds, the new certificate will ge returned in a new CertResource.
+// Please be aware that this function will return a new certificate in ANY case that is not an error.
+// If the server does not provide us with a new cert on a GET request to the CertURL
+// this function will start a new-cert flow where a new certificate gets generated.
+// If bundle is true, the []byte contains both the issuer certificate and
+// your issued certificate as a bundle.
+// For private key reuse the PrivateKey property of the passed in CertificateResource should be non-nil.
+func (c *Client) RenewCertificate(cert CertificateResource, bundle, mustStaple bool) (CertificateResource, error) {
+	// Input certificate is PEM encoded. Decode it here as we may need the decoded
+	// cert later on in the renewal process. The input may be a bundle or a single certificate.
+	certificates, err := parsePEMBundle(cert.Certificate)
+	if err != nil {
+		return CertificateResource{}, err
+	}
+
+	x509Cert := certificates[0]
+	if x509Cert.IsCA {
+		return CertificateResource{}, fmt.Errorf("[%s] Certificate bundle starts with a CA certificate", cert.Domain)
+	}
+
+	// This is just meant to be informal for the user.
+	timeLeft := x509Cert.NotAfter.Sub(time.Now().UTC())
+	logf("[INFO][%s] acme: Trying renewal with %d hours remaining", cert.Domain, int(timeLeft.Hours()))
+
+	// We always need to request a new certificate to renew.
+	// Start by checking to see if the certificate was based off a CSR, and
+	// use that if it's defined.
+	if len(cert.CSR) > 0 {
+		csr, err := pemDecodeTox509CSR(cert.CSR)
+		if err != nil {
+			return CertificateResource{}, err
+		}
+		newCert, failures := c.ObtainCertificateForCSR(*csr, bundle)
+		return newCert, failures[cert.Domain]
+	}
+
+	var privKey crypto.PrivateKey
+	if cert.PrivateKey != nil {
+		privKey, err = parsePEMPrivateKey(cert.PrivateKey)
+		if err != nil {
+			return CertificateResource{}, err
+		}
+	}
+
+	var domains []string
+	var failures map[string]error
+	// check for SAN certificate
+	if len(x509Cert.DNSNames) > 1 {
+		domains = append(domains, x509Cert.Subject.CommonName)
+		for _, sanDomain := range x509Cert.DNSNames {
+			if sanDomain == x509Cert.Subject.CommonName {
+				continue
+			}
+			domains = append(domains, sanDomain)
+		}
+	} else {
+		domains = append(domains, x509Cert.Subject.CommonName)
+	}
+
+	newCert, failures := c.ObtainCertificate(domains, bundle, privKey, mustStaple)
+	return newCert, failures[cert.Domain]
+}
+
+// Looks through the challenge combinations to find a solvable match.
+// Then solves the challenges in series and returns.
+func (c *Client) solveChallenges(challenges []authorizationResource) map[string]error {
+	// loop through the resources, basically through the domains.
+	failures := make(map[string]error)
+	for _, authz := range challenges {
+		if authz.Body.Status == "valid" {
+			// Boulder might recycle recent validated authz (see issue #267)
+			logf("[INFO][%s] acme: Authorization already valid; skipping challenge", authz.Domain)
+			continue
+		}
+		// no solvers - no solving
+		if solvers := c.chooseSolvers(authz.Body, authz.Domain); solvers != nil {
+			for i, solver := range solvers {
+				// TODO: do not immediately fail if one domain fails to validate.
+				err := solver.Solve(authz.Body.Challenges[i], authz.Domain)
+				if err != nil {
+					failures[authz.Domain] = err
+				}
+			}
+		} else {
+			failures[authz.Domain] = fmt.Errorf("[%s] acme: Could not determine solvers", authz.Domain)
+		}
+	}
+
+	return failures
+}
+
+// Checks all combinations from the server and returns an array of
+// solvers which should get executed in series.
+func (c *Client) chooseSolvers(auth authorization, domain string) map[int]solver {
+	for _, combination := range auth.Combinations {
+		solvers := make(map[int]solver)
+		for _, idx := range combination {
+			if solver, ok := c.solvers[auth.Challenges[idx].Type]; ok {
+				solvers[idx] = solver
+			} else {
+				logf("[INFO][%s] acme: Could not find solver for: %s", domain, auth.Challenges[idx].Type)
+			}
+		}
+
+		// If we can solve the whole combination, return the solvers
+		if len(solvers) == len(combination) {
+			return solvers
+		}
+	}
+	return nil
+}
+
+// Get the challenges needed to proof our identifier to the ACME server.
+func (c *Client) getChallenges(domains []string) ([]authorizationResource, map[string]error) {
+	resc, errc := make(chan authorizationResource), make(chan domainError)
+
+	for _, domain := range domains {
+		go func(domain string) {
+			authMsg := authorization{Resource: "new-authz", Identifier: identifier{Type: "dns", Value: domain}}
+			var authz authorization
+			hdr, err := postJSON(c.jws, c.user.GetRegistration().NewAuthzURL, authMsg, &authz)
+			if err != nil {
+				errc <- domainError{Domain: domain, Error: err}
+				return
+			}
+
+			links := parseLinks(hdr["Link"])
+			if links["next"] == "" {
+				logf("[ERROR][%s] acme: Server did not provide next link to proceed", domain)
+				return
+			}
+
+			resc <- authorizationResource{Body: authz, NewCertURL: links["next"], AuthURL: hdr.Get("Location"), Domain: domain}
+		}(domain)
+	}
+
+	responses := make(map[string]authorizationResource)
+	failures := make(map[string]error)
+	for i := 0; i < len(domains); i++ {
+		select {
+		case res := <-resc:
+			responses[res.Domain] = res
+		case err := <-errc:
+			failures[err.Domain] = err.Error
+		}
+	}
+
+	challenges := make([]authorizationResource, 0, len(responses))
+	for _, domain := range domains {
+		if challenge, ok := responses[domain]; ok {
+			challenges = append(challenges, challenge)
+		}
+	}
+
+	close(resc)
+	close(errc)
+
+	return challenges, failures
+}
+
+func (c *Client) requestCertificate(authz []authorizationResource, bundle bool, privKey crypto.PrivateKey, mustStaple bool) (CertificateResource, error) {
+	if len(authz) == 0 {
+		return CertificateResource{}, errors.New("Passed no authorizations to requestCertificate!")
+	}
+
+	var err error
+	if privKey == nil {
+		privKey, err = generatePrivateKey(c.keyType)
+		if err != nil {
+			return CertificateResource{}, err
+		}
+	}
+
+	// determine certificate name(s) based on the authorization resources
+	commonName := authz[0]
+	var san []string
+	for _, auth := range authz[1:] {
+		san = append(san, auth.Domain)
+	}
+
+	// TODO: should the CSR be customizable?
+	csr, err := generateCsr(privKey, commonName.Domain, san, mustStaple)
+	if err != nil {
+		return CertificateResource{}, err
+	}
+
+	return c.requestCertificateForCsr(authz, bundle, csr, pemEncode(privKey))
+}
+
+func (c *Client) requestCertificateForCsr(authz []authorizationResource, bundle bool, csr []byte, privateKeyPem []byte) (CertificateResource, error) {
+	commonName := authz[0]
+
+	var authURLs []string
+	for _, auth := range authz[1:] {
+		authURLs = append(authURLs, auth.AuthURL)
+	}
+
+	csrString := base64.URLEncoding.EncodeToString(csr)
+	jsonBytes, err := json.Marshal(csrMessage{Resource: "new-cert", Csr: csrString, Authorizations: authURLs})
+	if err != nil {
+		return CertificateResource{}, err
+	}
+
+	resp, err := c.jws.post(commonName.NewCertURL, jsonBytes)
+	if err != nil {
+		return CertificateResource{}, err
+	}
+
+	cerRes := CertificateResource{
+		Domain:     commonName.Domain,
+		CertURL:    resp.Header.Get("Location"),
+		PrivateKey: privateKeyPem}
+
+	for {
+		switch resp.StatusCode {
+		case 201, 202:
+			cert, err := ioutil.ReadAll(limitReader(resp.Body, 1024*1024))
+			resp.Body.Close()
+			if err != nil {
+				return CertificateResource{}, err
+			}
+
+			// The server returns a body with a length of zero if the
+			// certificate was not ready at the time this request completed.
+			// Otherwise the body is the certificate.
+			if len(cert) > 0 {
+
+				cerRes.CertStableURL = resp.Header.Get("Content-Location")
+				cerRes.AccountRef = c.user.GetRegistration().URI
+
+				issuedCert := pemEncode(derCertificateBytes(cert))
+
+				// The issuer certificate link is always supplied via an "up" link
+				// in the response headers of a new certificate.
+				links := parseLinks(resp.Header["Link"])
+				issuerCert, err := c.getIssuerCertificate(links["up"])
+				if err != nil {
+					// If we fail to acquire the issuer cert, return the issued certificate - do not fail.
+					logf("[WARNING][%s] acme: Could not bundle issuer certificate: %v", commonName.Domain, err)
+				} else {
+					issuerCert = pemEncode(derCertificateBytes(issuerCert))
+
+					// If bundle is true, we want to return a certificate bundle.
+					// To do this, we append the issuer cert to the issued cert.
+					if bundle {
+						issuedCert = append(issuedCert, issuerCert...)
+					}
+				}
+
+				cerRes.Certificate = issuedCert
+				cerRes.IssuerCertificate = issuerCert
+				logf("[INFO][%s] Server responded with a certificate.", commonName.Domain)
+				return cerRes, nil
+			}
+
+			// The certificate was granted but is not yet issued.
+			// Check retry-after and loop.
+			ra := resp.Header.Get("Retry-After")
+			retryAfter, err := strconv.Atoi(ra)
+			if err != nil {
+				return CertificateResource{}, err
+			}
+
+			logf("[INFO][%s] acme: Server responded with status 202; retrying after %ds", commonName.Domain, retryAfter)
+			time.Sleep(time.Duration(retryAfter) * time.Second)
+
+			break
+		default:
+			return CertificateResource{}, handleHTTPError(resp)
+		}
+
+		resp, err = httpGet(cerRes.CertURL)
+		if err != nil {
+			return CertificateResource{}, err
+		}
+	}
+}
+
+// getIssuerCertificate requests the issuer certificate
+func (c *Client) getIssuerCertificate(url string) ([]byte, error) {
+	logf("[INFO] acme: Requesting issuer cert from %s", url)
+	resp, err := httpGet(url)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	issuerBytes, err := ioutil.ReadAll(limitReader(resp.Body, 1024*1024))
+	if err != nil {
+		return nil, err
+	}
+
+	_, err = x509.ParseCertificate(issuerBytes)
+	if err != nil {
+		return nil, err
+	}
+
+	return issuerBytes, err
+}
+
+func parseLinks(links []string) map[string]string {
+	aBrkt := regexp.MustCompile("[<>]")
+	slver := regexp.MustCompile("(.+) *= *\"(.+)\"")
+	linkMap := make(map[string]string)
+
+	for _, link := range links {
+
+		link = aBrkt.ReplaceAllString(link, "")
+		parts := strings.Split(link, ";")
+
+		matches := slver.FindStringSubmatch(parts[1])
+		if len(matches) > 0 {
+			linkMap[matches[2]] = parts[0]
+		}
+	}
+
+	return linkMap
+}
+
+// validate makes the ACME server start validating a
+// challenge response, only returning once it is done.
+func validate(j *jws, domain, uri string, chlng challenge) error {
+	var challengeResponse challenge
+
+	hdr, err := postJSON(j, uri, chlng, &challengeResponse)
+	if err != nil {
+		return err
+	}
+
+	// After the path is sent, the ACME server will access our server.
+	// Repeatedly check the server for an updated status on our request.
+	for {
+		switch challengeResponse.Status {
+		case "valid":
+			logf("[INFO][%s] The server validated our request", domain)
+			return nil
+		case "pending":
+			break
+		case "invalid":
+			return handleChallengeError(challengeResponse)
+		default:
+			return errors.New("The server returned an unexpected state.")
+		}
+
+		ra, err := strconv.Atoi(hdr.Get("Retry-After"))
+		if err != nil {
+			// The ACME server MUST return a Retry-After.
+			// If it doesn't, we'll just poll hard.
+			ra = 1
+		}
+		time.Sleep(time.Duration(ra) * time.Second)
+
+		hdr, err = getJSON(uri, &challengeResponse)
+		if err != nil {
+			return err
+		}
+	}
+}

vendor/github.com/xenolf/lego/acme/crypto.go

@@ -0,0 +1,347 @@
+package acme
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/base64"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"math/big"
+	"net/http"
+	"strings"
+	"time"
+
+	"encoding/asn1"
+
+	"golang.org/x/crypto/ocsp"
+)
+
+// KeyType represents the key algo as well as the key size or curve to use.
+type KeyType string
+type derCertificateBytes []byte
+
+// Constants for all key types we support.
+const (
+	EC256   = KeyType("P256")
+	EC384   = KeyType("P384")
+	RSA2048 = KeyType("2048")
+	RSA4096 = KeyType("4096")
+	RSA8192 = KeyType("8192")
+)
+
+const (
+	// OCSPGood means that the certificate is valid.
+	OCSPGood = ocsp.Good
+	// OCSPRevoked means that the certificate has been deliberately revoked.
+	OCSPRevoked = ocsp.Revoked
+	// OCSPUnknown means that the OCSP responder doesn't know about the certificate.
+	OCSPUnknown = ocsp.Unknown
+	// OCSPServerFailed means that the OCSP responder failed to process the request.
+	OCSPServerFailed = ocsp.ServerFailed
+)
+
+// Constants for OCSP must staple
+var (
+	tlsFeatureExtensionOID = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 1, 24}
+	ocspMustStapleFeature  = []byte{0x30, 0x03, 0x02, 0x01, 0x05}
+)
+
+// GetOCSPForCert takes a PEM encoded cert or cert bundle returning the raw OCSP response,
+// the parsed response, and an error, if any. The returned []byte can be passed directly
+// into the OCSPStaple property of a tls.Certificate. If the bundle only contains the
+// issued certificate, this function will try to get the issuer certificate from the
+// IssuingCertificateURL in the certificate. If the []byte and/or ocsp.Response return
+// values are nil, the OCSP status may be assumed OCSPUnknown.
+func GetOCSPForCert(bundle []byte) ([]byte, *ocsp.Response, error) {
+	certificates, err := parsePEMBundle(bundle)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// We expect the certificate slice to be ordered downwards the chain.
+	// SRV CRT -> CA. We need to pull the leaf and issuer certs out of it,
+	// which should always be the first two certificates. If there's no
+	// OCSP server listed in the leaf cert, there's nothing to do. And if
+	// we have only one certificate so far, we need to get the issuer cert.
+	issuedCert := certificates[0]
+	if len(issuedCert.OCSPServer) == 0 {
+		return nil, nil, errors.New("no OCSP server specified in cert")
+	}
+	if len(certificates) == 1 {
+		// TODO: build fallback. If this fails, check the remaining array entries.
+		if len(issuedCert.IssuingCertificateURL) == 0 {
+			return nil, nil, errors.New("no issuing certificate URL")
+		}
+
+		resp, err := httpGet(issuedCert.IssuingCertificateURL[0])
+		if err != nil {
+			return nil, nil, err
+		}
+		defer resp.Body.Close()
+
+		issuerBytes, err := ioutil.ReadAll(limitReader(resp.Body, 1024*1024))
+		if err != nil {
+			return nil, nil, err
+		}
+
+		issuerCert, err := x509.ParseCertificate(issuerBytes)
+		if err != nil {
+			return nil, nil, err
+		}
+
+		// Insert it into the slice on position 0
+		// We want it ordered right SRV CRT -> CA
+		certificates = append(certificates, issuerCert)
+	}
+	issuerCert := certificates[1]
+
+	// Finally kick off the OCSP request.
+	ocspReq, err := ocsp.CreateRequest(issuedCert, issuerCert, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	reader := bytes.NewReader(ocspReq)
+	req, err := httpPost(issuedCert.OCSPServer[0], "application/ocsp-request", reader)
+	if err != nil {
+		return nil, nil, err
+	}
+	defer req.Body.Close()
+
+	ocspResBytes, err := ioutil.ReadAll(limitReader(req.Body, 1024*1024))
+	ocspRes, err := ocsp.ParseResponse(ocspResBytes, issuerCert)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return ocspResBytes, ocspRes, nil
+}
+
+func getKeyAuthorization(token string, key interface{}) (string, error) {
+	var publicKey crypto.PublicKey
+	switch k := key.(type) {
+	case *ecdsa.PrivateKey:
+		publicKey = k.Public()
+	case *rsa.PrivateKey:
+		publicKey = k.Public()
+	}
+
+	// Generate the Key Authorization for the challenge
+	jwk := keyAsJWK(publicKey)
+	if jwk == nil {
+		return "", errors.New("Could not generate JWK from key.")
+	}
+	thumbBytes, err := jwk.Thumbprint(crypto.SHA256)
+	if err != nil {
+		return "", err
+	}
+
+	// unpad the base64URL
+	keyThumb := base64.URLEncoding.EncodeToString(thumbBytes)
+	index := strings.Index(keyThumb, "=")
+	if index != -1 {
+		keyThumb = keyThumb[:index]
+	}
+
+	return token + "." + keyThumb, nil
+}
+
+// parsePEMBundle parses a certificate bundle from top to bottom and returns
+// a slice of x509 certificates. This function will error if no certificates are found.
+func parsePEMBundle(bundle []byte) ([]*x509.Certificate, error) {
+	var certificates []*x509.Certificate
+	var certDERBlock *pem.Block
+
+	for {
+		certDERBlock, bundle = pem.Decode(bundle)
+		if certDERBlock == nil {
+			break
+		}
+
+		if certDERBlock.Type == "CERTIFICATE" {
+			cert, err := x509.ParseCertificate(certDERBlock.Bytes)
+			if err != nil {
+				return nil, err
+			}
+			certificates = append(certificates, cert)
+		}
+	}
+
+	if len(certificates) == 0 {
+		return nil, errors.New("No certificates were found while parsing the bundle.")
+	}
+
+	return certificates, nil
+}
+
+func parsePEMPrivateKey(key []byte) (crypto.PrivateKey, error) {
+	keyBlock, _ := pem.Decode(key)
+
+	switch keyBlock.Type {
+	case "RSA PRIVATE KEY":
+		return x509.ParsePKCS1PrivateKey(keyBlock.Bytes)
+	case "EC PRIVATE KEY":
+		return x509.ParseECPrivateKey(keyBlock.Bytes)
+	default:
+		return nil, errors.New("Unknown PEM header value")
+	}
+}
+
+func generatePrivateKey(keyType KeyType) (crypto.PrivateKey, error) {
+
+	switch keyType {
+	case EC256:
+		return ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	case EC384:
+		return ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
+	case RSA2048:
+		return rsa.GenerateKey(rand.Reader, 2048)
+	case RSA4096:
+		return rsa.GenerateKey(rand.Reader, 4096)
+	case RSA8192:
+		return rsa.GenerateKey(rand.Reader, 8192)
+	}
+
+	return nil, fmt.Errorf("Invalid KeyType: %s", keyType)
+}
+
+func generateCsr(privateKey crypto.PrivateKey, domain string, san []string, mustStaple bool) ([]byte, error) {
+	template := x509.CertificateRequest{
+		Subject: pkix.Name{
+			CommonName: domain,
+		},
+	}
+
+	if len(san) > 0 {
+		template.DNSNames = san
+	}
+
+	if mustStaple {
+		template.ExtraExtensions = append(template.ExtraExtensions, pkix.Extension{
+			Id:    tlsFeatureExtensionOID,
+			Value: ocspMustStapleFeature,
+		})
+	}
+
+	return x509.CreateCertificateRequest(rand.Reader, &template, privateKey)
+}
+
+func pemEncode(data interface{}) []byte {
+	var pemBlock *pem.Block
+	switch key := data.(type) {
+	case *ecdsa.PrivateKey:
+		keyBytes, _ := x509.MarshalECPrivateKey(key)
+		pemBlock = &pem.Block{Type: "EC PRIVATE KEY", Bytes: keyBytes}
+	case *rsa.PrivateKey:
+		pemBlock = &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(key)}
+		break
+	case *x509.CertificateRequest:
+		pemBlock = &pem.Block{Type: "CERTIFICATE REQUEST", Bytes: key.Raw}
+		break
+	case derCertificateBytes:
+		pemBlock = &pem.Block{Type: "CERTIFICATE", Bytes: []byte(data.(derCertificateBytes))}
+	}
+
+	return pem.EncodeToMemory(pemBlock)
+}
+
+func pemDecode(data []byte) (*pem.Block, error) {
+	pemBlock, _ := pem.Decode(data)
+	if pemBlock == nil {
+		return nil, fmt.Errorf("Pem decode did not yield a valid block. Is the certificate in the right format?")
+	}
+
+	return pemBlock, nil
+}
+
+func pemDecodeTox509(pem []byte) (*x509.Certificate, error) {
+	pemBlock, err := pemDecode(pem)
+	if pemBlock == nil {
+		return nil, err
+	}
+
+	return x509.ParseCertificate(pemBlock.Bytes)
+}
+
+func pemDecodeTox509CSR(pem []byte) (*x509.CertificateRequest, error) {
+	pemBlock, err := pemDecode(pem)
+	if pemBlock == nil {
+		return nil, err
+	}
+
+	if pemBlock.Type != "CERTIFICATE REQUEST" {
+		return nil, fmt.Errorf("PEM block is not a certificate request")
+	}
+
+	return x509.ParseCertificateRequest(pemBlock.Bytes)
+}
+
+// GetPEMCertExpiration returns the "NotAfter" date of a PEM encoded certificate.
+// The certificate has to be PEM encoded. Any other encodings like DER will fail.
+func GetPEMCertExpiration(cert []byte) (time.Time, error) {
+	pemBlock, err := pemDecode(cert)
+	if pemBlock == nil {
+		return time.Time{}, err
+	}
+
+	return getCertExpiration(pemBlock.Bytes)
+}
+
+// getCertExpiration returns the "NotAfter" date of a DER encoded certificate.
+func getCertExpiration(cert []byte) (time.Time, error) {
+	pCert, err := x509.ParseCertificate(cert)
+	if err != nil {
+		return time.Time{}, err
+	}
+
+	return pCert.NotAfter, nil
+}
+
+func generatePemCert(privKey *rsa.PrivateKey, domain string) ([]byte, error) {
+	derBytes, err := generateDerCert(privKey, time.Time{}, domain)
+	if err != nil {
+		return nil, err
+	}
+
+	return pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: derBytes}), nil
+}
+
+func generateDerCert(privKey *rsa.PrivateKey, expiration time.Time, domain string) ([]byte, error) {
+	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
+	serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
+	if err != nil {
+		return nil, err
+	}
+
+	if expiration.IsZero() {
+		expiration = time.Now().Add(365)
+	}
+
+	template := x509.Certificate{
+		SerialNumber: serialNumber,
+		Subject: pkix.Name{
+			CommonName: "ACME Challenge TEMP",
+		},
+		NotBefore: time.Now(),
+		NotAfter:  expiration,
+
+		KeyUsage:              x509.KeyUsageKeyEncipherment,
+		BasicConstraintsValid: true,
+		DNSNames:              []string{domain},
+	}
+
+	return x509.CreateCertificate(rand.Reader, &template, &template, &privKey.PublicKey, privKey)
+}
+
+func limitReader(rd io.ReadCloser, numBytes int64) io.ReadCloser {
+	return http.MaxBytesReader(nil, rd, numBytes)
+}

vendor/github.com/xenolf/lego/acme/dns_challenge.go

@@ -0,0 +1,305 @@
+package acme
+
+import (
+	"crypto/sha256"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"log"
+	"net"
+	"strings"
+	"time"
+
+	"github.com/miekg/dns"
+	"golang.org/x/net/publicsuffix"
+)
+
+type preCheckDNSFunc func(fqdn, value string) (bool, error)
+
+var (
+	// PreCheckDNS checks DNS propagation before notifying ACME that
+	// the DNS challenge is ready.
+	PreCheckDNS preCheckDNSFunc = checkDNSPropagation
+	fqdnToZone                  = map[string]string{}
+)
+
+const defaultResolvConf = "/etc/resolv.conf"
+
+var defaultNameservers = []string{
+	"google-public-dns-a.google.com:53",
+	"google-public-dns-b.google.com:53",
+}
+
+var RecursiveNameservers = getNameservers(defaultResolvConf, defaultNameservers)
+
+// DNSTimeout is used to override the default DNS timeout of 10 seconds.
+var DNSTimeout = 10 * time.Second
+
+// getNameservers attempts to get systems nameservers before falling back to the defaults
+func getNameservers(path string, defaults []string) []string {
+	config, err := dns.ClientConfigFromFile(path)
+	if err != nil || len(config.Servers) == 0 {
+		return defaults
+	}
+
+	systemNameservers := []string{}
+	for _, server := range config.Servers {
+		// ensure all servers have a port number
+		if _, _, err := net.SplitHostPort(server); err != nil {
+			systemNameservers = append(systemNameservers, net.JoinHostPort(server, "53"))
+		} else {
+			systemNameservers = append(systemNameservers, server)
+		}
+	}
+	return systemNameservers
+}
+
+// DNS01Record returns a DNS record which will fulfill the `dns-01` challenge
+func DNS01Record(domain, keyAuth string) (fqdn string, value string, ttl int) {
+	keyAuthShaBytes := sha256.Sum256([]byte(keyAuth))
+	// base64URL encoding without padding
+	keyAuthSha := base64.URLEncoding.EncodeToString(keyAuthShaBytes[:sha256.Size])
+	value = strings.TrimRight(keyAuthSha, "=")
+	ttl = 120
+	fqdn = fmt.Sprintf("_acme-challenge.%s.", domain)
+	return
+}
+
+// dnsChallenge implements the dns-01 challenge according to ACME 7.5
+type dnsChallenge struct {
+	jws      *jws
+	validate validateFunc
+	provider ChallengeProvider
+}
+
+func (s *dnsChallenge) Solve(chlng challenge, domain string) error {
+	logf("[INFO][%s] acme: Trying to solve DNS-01", domain)
+
+	if s.provider == nil {
+		return errors.New("No DNS Provider configured")
+	}
+
+	// Generate the Key Authorization for the challenge
+	keyAuth, err := getKeyAuthorization(chlng.Token, s.jws.privKey)
+	if err != nil {
+		return err
+	}
+
+	err = s.provider.Present(domain, chlng.Token, keyAuth)
+	if err != nil {
+		return fmt.Errorf("Error presenting token: %s", err)
+	}
+	defer func() {
+		err := s.provider.CleanUp(domain, chlng.Token, keyAuth)
+		if err != nil {
+			log.Printf("Error cleaning up %s: %v ", domain, err)
+		}
+	}()
+
+	fqdn, value, _ := DNS01Record(domain, keyAuth)
+
+	logf("[INFO][%s] Checking DNS record propagation using %+v", domain, RecursiveNameservers)
+
+	var timeout, interval time.Duration
+	switch provider := s.provider.(type) {
+	case ChallengeProviderTimeout:
+		timeout, interval = provider.Timeout()
+	default:
+		timeout, interval = 60*time.Second, 2*time.Second
+	}
+
+	err = WaitFor(timeout, interval, func() (bool, error) {
+		return PreCheckDNS(fqdn, value)
+	})
+	if err != nil {
+		return err
+	}
+
+	return s.validate(s.jws, domain, chlng.URI, challenge{Resource: "challenge", Type: chlng.Type, Token: chlng.Token, KeyAuthorization: keyAuth})
+}
+
+// checkDNSPropagation checks if the expected TXT record has been propagated to all authoritative nameservers.
+func checkDNSPropagation(fqdn, value string) (bool, error) {
+	// Initial attempt to resolve at the recursive NS
+	r, err := dnsQuery(fqdn, dns.TypeTXT, RecursiveNameservers, true)
+	if err != nil {
+		return false, err
+	}
+	if r.Rcode == dns.RcodeSuccess {
+		// If we see a CNAME here then use the alias
+		for _, rr := range r.Answer {
+			if cn, ok := rr.(*dns.CNAME); ok {
+				if cn.Hdr.Name == fqdn {
+					fqdn = cn.Target
+					break
+				}
+			}
+		}
+	}
+
+	authoritativeNss, err := lookupNameservers(fqdn)
+	if err != nil {
+		return false, err
+	}
+
+	return checkAuthoritativeNss(fqdn, value, authoritativeNss)
+}
+
+// checkAuthoritativeNss queries each of the given nameservers for the expected TXT record.
+func checkAuthoritativeNss(fqdn, value string, nameservers []string) (bool, error) {
+	for _, ns := range nameservers {
+		r, err := dnsQuery(fqdn, dns.TypeTXT, []string{net.JoinHostPort(ns, "53")}, false)
+		if err != nil {
+			return false, err
+		}
+
+		if r.Rcode != dns.RcodeSuccess {
+			return false, fmt.Errorf("NS %s returned %s for %s", ns, dns.RcodeToString[r.Rcode], fqdn)
+		}
+
+		var found bool
+		for _, rr := range r.Answer {
+			if txt, ok := rr.(*dns.TXT); ok {
+				if strings.Join(txt.Txt, "") == value {
+					found = true
+					break
+				}
+			}
+		}
+
+		if !found {
+			return false, fmt.Errorf("NS %s did not return the expected TXT record", ns)
+		}
+	}
+
+	return true, nil
+}
+
+// dnsQuery will query a nameserver, iterating through the supplied servers as it retries
+// The nameserver should include a port, to facilitate testing where we talk to a mock dns server.
+func dnsQuery(fqdn string, rtype uint16, nameservers []string, recursive bool) (in *dns.Msg, err error) {
+	m := new(dns.Msg)
+	m.SetQuestion(fqdn, rtype)
+	m.SetEdns0(4096, false)
+
+	if !recursive {
+		m.RecursionDesired = false
+	}
+
+	// Will retry the request based on the number of servers (n+1)
+	for i := 1; i <= len(nameservers)+1; i++ {
+		ns := nameservers[i%len(nameservers)]
+		udp := &dns.Client{Net: "udp", Timeout: DNSTimeout}
+		in, _, err = udp.Exchange(m, ns)
+
+		if err == dns.ErrTruncated {
+			tcp := &dns.Client{Net: "tcp", Timeout: DNSTimeout}
+			// If the TCP request suceeds, the err will reset to nil
+			in, _, err = tcp.Exchange(m, ns)
+		}
+
+		if err == nil {
+			break
+		}
+	}
+	return
+}
+
+// lookupNameservers returns the authoritative nameservers for the given fqdn.
+func lookupNameservers(fqdn string) ([]string, error) {
+	var authoritativeNss []string
+
+	zone, err := FindZoneByFqdn(fqdn, RecursiveNameservers)
+	if err != nil {
+		return nil, fmt.Errorf("Could not determine the zone: %v", err)
+	}
+
+	r, err := dnsQuery(zone, dns.TypeNS, RecursiveNameservers, true)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, rr := range r.Answer {
+		if ns, ok := rr.(*dns.NS); ok {
+			authoritativeNss = append(authoritativeNss, strings.ToLower(ns.Ns))
+		}
+	}
+
+	if len(authoritativeNss) > 0 {
+		return authoritativeNss, nil
+	}
+	return nil, fmt.Errorf("Could not determine authoritative nameservers")
+}
+
+// FindZoneByFqdn determines the zone apex for the given fqdn by recursing up the
+// domain labels until the nameserver returns a SOA record in the answer section.
+func FindZoneByFqdn(fqdn string, nameservers []string) (string, error) {
+	// Do we have it cached?
+	if zone, ok := fqdnToZone[fqdn]; ok {
+		return zone, nil
+	}
+
+	labelIndexes := dns.Split(fqdn)
+	for _, index := range labelIndexes {
+		domain := fqdn[index:]
+		// Give up if we have reached the TLD
+		if isTLD(domain) {
+			break
+		}
+
+		in, err := dnsQuery(domain, dns.TypeSOA, nameservers, true)
+		if err != nil {
+			return "", err
+		}
+
+		// Any response code other than NOERROR and NXDOMAIN is treated as error
+		if in.Rcode != dns.RcodeNameError && in.Rcode != dns.RcodeSuccess {
+			return "", fmt.Errorf("Unexpected response code '%s' for %s",
+				dns.RcodeToString[in.Rcode], domain)
+		}
+
+		// Check if we got a SOA RR in the answer section
+		if in.Rcode == dns.RcodeSuccess {
+			for _, ans := range in.Answer {
+				if soa, ok := ans.(*dns.SOA); ok {
+					zone := soa.Hdr.Name
+					fqdnToZone[fqdn] = zone
+					return zone, nil
+				}
+			}
+		}
+	}
+
+	return "", fmt.Errorf("Could not find the start of authority")
+}
+
+func isTLD(domain string) bool {
+	publicsuffix, _ := publicsuffix.PublicSuffix(UnFqdn(domain))
+	if publicsuffix == UnFqdn(domain) {
+		return true
+	}
+	return false
+}
+
+// ClearFqdnCache clears the cache of fqdn to zone mappings. Primarily used in testing.
+func ClearFqdnCache() {
+	fqdnToZone = map[string]string{}
+}
+
+// ToFqdn converts the name into a fqdn appending a trailing dot.
+func ToFqdn(name string) string {
+	n := len(name)
+	if n == 0 || name[n-1] == '.' {
+		return name
+	}
+	return name + "."
+}
+
+// UnFqdn converts the fqdn into a name removing the trailing dot.
+func UnFqdn(name string) string {
+	n := len(name)
+	if n != 0 && name[n-1] == '.' {
+		return name[:n-1]
+	}
+	return name
+}

vendor/github.com/xenolf/lego/acme/dns_challenge_manual.go

@@ -0,0 +1,53 @@
+package acme
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+const (
+	dnsTemplate = "%s %d IN TXT \"%s\""
+)
+
+// DNSProviderManual is an implementation of the ChallengeProvider interface
+type DNSProviderManual struct{}
+
+// NewDNSProviderManual returns a DNSProviderManual instance.
+func NewDNSProviderManual() (*DNSProviderManual, error) {
+	return &DNSProviderManual{}, nil
+}
+
+// Present prints instructions for manually creating the TXT record
+func (*DNSProviderManual) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := DNS01Record(domain, keyAuth)
+	dnsRecord := fmt.Sprintf(dnsTemplate, fqdn, ttl, value)
+
+	authZone, err := FindZoneByFqdn(fqdn, RecursiveNameservers)
+	if err != nil {
+		return err
+	}
+
+	logf("[INFO] acme: Please create the following TXT record in your %s zone:", authZone)
+	logf("[INFO] acme: %s", dnsRecord)
+	logf("[INFO] acme: Press 'Enter' when you are done")
+
+	reader := bufio.NewReader(os.Stdin)
+	_, _ = reader.ReadString('\n')
+	return nil
+}
+
+// CleanUp prints instructions for manually removing the TXT record
+func (*DNSProviderManual) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, ttl := DNS01Record(domain, keyAuth)
+	dnsRecord := fmt.Sprintf(dnsTemplate, fqdn, ttl, "...")
+
+	authZone, err := FindZoneByFqdn(fqdn, RecursiveNameservers)
+	if err != nil {
+		return err
+	}
+
+	logf("[INFO] acme: You can now remove this TXT record from your %s zone:", authZone)
+	logf("[INFO] acme: %s", dnsRecord)
+	return nil
+}

vendor/github.com/xenolf/lego/acme/error.go

@@ -0,0 +1,86 @@
+package acme
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"strings"
+)
+
+const (
+	tosAgreementError = "Must agree to subscriber agreement before any further actions"
+)
+
+// RemoteError is the base type for all errors specific to the ACME protocol.
+type RemoteError struct {
+	StatusCode int    `json:"status,omitempty"`
+	Type       string `json:"type"`
+	Detail     string `json:"detail"`
+}
+
+func (e RemoteError) Error() string {
+	return fmt.Sprintf("acme: Error %d - %s - %s", e.StatusCode, e.Type, e.Detail)
+}
+
+// TOSError represents the error which is returned if the user needs to
+// accept the TOS.
+// TODO: include the new TOS url if we can somehow obtain it.
+type TOSError struct {
+	RemoteError
+}
+
+type domainError struct {
+	Domain string
+	Error  error
+}
+
+type challengeError struct {
+	RemoteError
+	records []validationRecord
+}
+
+func (c challengeError) Error() string {
+
+	var errStr string
+	for _, validation := range c.records {
+		errStr = errStr + fmt.Sprintf("\tValidation for %s:%s\n\tResolved to:\n\t\t%s\n\tUsed: %s\n\n",
+			validation.Hostname, validation.Port, strings.Join(validation.ResolvedAddresses, "\n\t\t"), validation.UsedAddress)
+	}
+
+	return fmt.Sprintf("%s\nError Detail:\n%s", c.RemoteError.Error(), errStr)
+}
+
+func handleHTTPError(resp *http.Response) error {
+	var errorDetail RemoteError
+
+	contenType := resp.Header.Get("Content-Type")
+	// try to decode the content as JSON
+	if contenType == "application/json" || contenType == "application/problem+json" {
+		decoder := json.NewDecoder(resp.Body)
+		err := decoder.Decode(&errorDetail)
+		if err != nil {
+			return err
+		}
+	} else {
+		detailBytes, err := ioutil.ReadAll(limitReader(resp.Body, 1024*1024))
+		if err != nil {
+			return err
+		}
+
+		errorDetail.Detail = string(detailBytes)
+	}
+
+	errorDetail.StatusCode = resp.StatusCode
+
+	// Check for errors we handle specifically
+	if errorDetail.StatusCode == http.StatusForbidden && errorDetail.Detail == tosAgreementError {
+		return TOSError{errorDetail}
+	}
+
+	return errorDetail
+}
+
+func handleChallengeError(chlng challenge) error {
+	return challengeError{chlng.Error, chlng.ValidationRecords}
+}

vendor/github.com/xenolf/lego/acme/http.go

@@ -0,0 +1,117 @@
+package acme
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"runtime"
+	"strings"
+	"time"
+)
+
+// UserAgent (if non-empty) will be tacked onto the User-Agent string in requests.
+var UserAgent string
+
+// HTTPClient is an HTTP client with a reasonable timeout value.
+var HTTPClient = http.Client{Timeout: 10 * time.Second}
+
+const (
+	// defaultGoUserAgent is the Go HTTP package user agent string. Too
+	// bad it isn't exported. If it changes, we should update it here, too.
+	defaultGoUserAgent = "Go-http-client/1.1"
+
+	// ourUserAgent is the User-Agent of this underlying library package.
+	ourUserAgent = "xenolf-acme"
+)
+
+// httpHead performs a HEAD request with a proper User-Agent string.
+// The response body (resp.Body) is already closed when this function returns.
+func httpHead(url string) (resp *http.Response, err error) {
+	req, err := http.NewRequest("HEAD", url, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Set("User-Agent", userAgent())
+
+	resp, err = HTTPClient.Do(req)
+	if err != nil {
+		return resp, err
+	}
+	resp.Body.Close()
+	return resp, err
+}
+
+// httpPost performs a POST request with a proper User-Agent string.
+// Callers should close resp.Body when done reading from it.
+func httpPost(url string, bodyType string, body io.Reader) (resp *http.Response, err error) {
+	req, err := http.NewRequest("POST", url, body)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", bodyType)
+	req.Header.Set("User-Agent", userAgent())
+
+	return HTTPClient.Do(req)
+}
+
+// httpGet performs a GET request with a proper User-Agent string.
+// Callers should close resp.Body when done reading from it.
+func httpGet(url string) (resp *http.Response, err error) {
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("User-Agent", userAgent())
+
+	return HTTPClient.Do(req)
+}
+
+// getJSON performs an HTTP GET request and parses the response body
+// as JSON, into the provided respBody object.
+func getJSON(uri string, respBody interface{}) (http.Header, error) {
+	resp, err := httpGet(uri)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get %q: %v", uri, err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= http.StatusBadRequest {
+		return resp.Header, handleHTTPError(resp)
+	}
+
+	return resp.Header, json.NewDecoder(resp.Body).Decode(respBody)
+}
+
+// postJSON performs an HTTP POST request and parses the response body
+// as JSON, into the provided respBody object.
+func postJSON(j *jws, uri string, reqBody, respBody interface{}) (http.Header, error) {
+	jsonBytes, err := json.Marshal(reqBody)
+	if err != nil {
+		return nil, errors.New("Failed to marshal network message...")
+	}
+
+	resp, err := j.post(uri, jsonBytes)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to post JWS message. -> %v", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= http.StatusBadRequest {
+		return resp.Header, handleHTTPError(resp)
+	}
+
+	if respBody == nil {
+		return resp.Header, nil
+	}
+
+	return resp.Header, json.NewDecoder(resp.Body).Decode(respBody)
+}
+
+// userAgent builds and returns the User-Agent string to use in requests.
+func userAgent() string {
+	ua := fmt.Sprintf("%s (%s; %s) %s %s", defaultGoUserAgent, runtime.GOOS, runtime.GOARCH, ourUserAgent, UserAgent)
+	return strings.TrimSpace(ua)
+}

vendor/github.com/xenolf/lego/acme/http_challenge.go

@@ -0,0 +1,41 @@
+package acme
+
+import (
+	"fmt"
+	"log"
+)
+
+type httpChallenge struct {
+	jws      *jws
+	validate validateFunc
+	provider ChallengeProvider
+}
+
+// HTTP01ChallengePath returns the URL path for the `http-01` challenge
+func HTTP01ChallengePath(token string) string {
+	return "/.well-known/acme-challenge/" + token
+}
+
+func (s *httpChallenge) Solve(chlng challenge, domain string) error {
+
+	logf("[INFO][%s] acme: Trying to solve HTTP-01", domain)
+
+	// Generate the Key Authorization for the challenge
+	keyAuth, err := getKeyAuthorization(chlng.Token, s.jws.privKey)
+	if err != nil {
+		return err
+	}
+
+	err = s.provider.Present(domain, chlng.Token, keyAuth)
+	if err != nil {
+		return fmt.Errorf("[%s] error presenting token: %v", domain, err)
+	}
+	defer func() {
+		err := s.provider.CleanUp(domain, chlng.Token, keyAuth)
+		if err != nil {
+			log.Printf("[%s] error cleaning up: %v", domain, err)
+		}
+	}()
+
+	return s.validate(s.jws, domain, chlng.URI, challenge{Resource: "challenge", Type: chlng.Type, Token: chlng.Token, KeyAuthorization: keyAuth})
+}

vendor/github.com/xenolf/lego/acme/http_challenge_server.go

@@ -0,0 +1,79 @@
+package acme
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"strings"
+)
+
+// HTTPProviderServer implements ChallengeProvider for `http-01` challenge
+// It may be instantiated without using the NewHTTPProviderServer function if
+// you want only to use the default values.
+type HTTPProviderServer struct {
+	iface    string
+	port     string
+	done     chan bool
+	listener net.Listener
+}
+
+// NewHTTPProviderServer creates a new HTTPProviderServer on the selected interface and port.
+// Setting iface and / or port to an empty string will make the server fall back to
+// the "any" interface and port 80 respectively.
+func NewHTTPProviderServer(iface, port string) *HTTPProviderServer {
+	return &HTTPProviderServer{iface: iface, port: port}
+}
+
+// Present starts a web server and makes the token available at `HTTP01ChallengePath(token)` for web requests.
+func (s *HTTPProviderServer) Present(domain, token, keyAuth string) error {
+	if s.port == "" {
+		s.port = "80"
+	}
+
+	var err error
+	s.listener, err = net.Listen("tcp", net.JoinHostPort(s.iface, s.port))
+	if err != nil {
+		return fmt.Errorf("Could not start HTTP server for challenge -> %v", err)
+	}
+
+	s.done = make(chan bool)
+	go s.serve(domain, token, keyAuth)
+	return nil
+}
+
+// CleanUp closes the HTTP server and removes the token from `HTTP01ChallengePath(token)`
+func (s *HTTPProviderServer) CleanUp(domain, token, keyAuth string) error {
+	if s.listener == nil {
+		return nil
+	}
+	s.listener.Close()
+	<-s.done
+	return nil
+}
+
+func (s *HTTPProviderServer) serve(domain, token, keyAuth string) {
+	path := HTTP01ChallengePath(token)
+
+	// The handler validates the HOST header and request type.
+	// For validation it then writes the token the server returned with the challenge
+	mux := http.NewServeMux()
+	mux.HandleFunc(path, func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasPrefix(r.Host, domain) && r.Method == "GET" {
+			w.Header().Add("Content-Type", "text/plain")
+			w.Write([]byte(keyAuth))
+			logf("[INFO][%s] Served key authentication", domain)
+		} else {
+			logf("[WARN] Received request for domain %s with method %s but the domain did not match any challenge. Please ensure your are passing the HOST header properly.", r.Host, r.Method)
+			w.Write([]byte("TEST"))
+		}
+	})
+
+	httpServer := &http.Server{
+		Handler: mux,
+	}
+	// Once httpServer is shut down we don't want any lingering
+	// connections, so disable KeepAlives.
+	httpServer.SetKeepAlivesEnabled(false)
+	httpServer.Serve(s.listener)
+	s.done <- true
+}

vendor/github.com/xenolf/lego/acme/jws.go

@@ -0,0 +1,115 @@
+package acme
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rsa"
+	"fmt"
+	"net/http"
+	"sync"
+
+	"gopkg.in/square/go-jose.v1"
+)
+
+type jws struct {
+	directoryURL string
+	privKey      crypto.PrivateKey
+	nonces       []string
+	sync.Mutex
+}
+
+func keyAsJWK(key interface{}) *jose.JsonWebKey {
+	switch k := key.(type) {
+	case *ecdsa.PublicKey:
+		return &jose.JsonWebKey{Key: k, Algorithm: "EC"}
+	case *rsa.PublicKey:
+		return &jose.JsonWebKey{Key: k, Algorithm: "RSA"}
+
+	default:
+		return nil
+	}
+}
+
+// Posts a JWS signed message to the specified URL
+func (j *jws) post(url string, content []byte) (*http.Response, error) {
+	signedContent, err := j.signContent(content)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := httpPost(url, "application/jose+json", bytes.NewBuffer([]byte(signedContent.FullSerialize())))
+	if err != nil {
+		return nil, err
+	}
+
+	j.Lock()
+	defer j.Unlock()
+	j.getNonceFromResponse(resp)
+
+	return resp, err
+}
+
+func (j *jws) signContent(content []byte) (*jose.JsonWebSignature, error) {
+
+	var alg jose.SignatureAlgorithm
+	switch k := j.privKey.(type) {
+	case *rsa.PrivateKey:
+		alg = jose.RS256
+	case *ecdsa.PrivateKey:
+		if k.Curve == elliptic.P256() {
+			alg = jose.ES256
+		} else if k.Curve == elliptic.P384() {
+			alg = jose.ES384
+		}
+	}
+
+	signer, err := jose.NewSigner(alg, j.privKey)
+	if err != nil {
+		return nil, err
+	}
+	signer.SetNonceSource(j)
+
+	signed, err := signer.Sign(content)
+	if err != nil {
+		return nil, err
+	}
+	return signed, nil
+}
+
+func (j *jws) getNonceFromResponse(resp *http.Response) error {
+	nonce := resp.Header.Get("Replay-Nonce")
+	if nonce == "" {
+		return fmt.Errorf("Server did not respond with a proper nonce header.")
+	}
+
+	j.nonces = append(j.nonces, nonce)
+	return nil
+}
+
+func (j *jws) getNonce() error {
+	resp, err := httpHead(j.directoryURL)
+	if err != nil {
+		return err
+	}
+
+	return j.getNonceFromResponse(resp)
+}
+
+func (j *jws) Nonce() (string, error) {
+	j.Lock()
+	defer j.Unlock()
+	nonce := ""
+	if len(j.nonces) == 0 {
+		err := j.getNonce()
+		if err != nil {
+			return nonce, err
+		}
+	}
+	if len(j.nonces) == 0 {
+		return "", fmt.Errorf("Can't get nonce")
+	}
+	nonce, j.nonces = j.nonces[len(j.nonces)-1], j.nonces[:len(j.nonces)-1]
+	return nonce, nil
+}

vendor/github.com/xenolf/lego/acme/messages.go

@@ -0,0 +1,110 @@
+package acme
+
+import (
+	"time"
+
+	"gopkg.in/square/go-jose.v1"
+)
+
+type directory struct {
+	NewAuthzURL   string `json:"new-authz"`
+	NewCertURL    string `json:"new-cert"`
+	NewRegURL     string `json:"new-reg"`
+	RevokeCertURL string `json:"revoke-cert"`
+}
+
+type registrationMessage struct {
+	Resource string   `json:"resource"`
+	Contact  []string `json:"contact"`
+	Delete   bool     `json:"delete,omitempty"`
+}
+
+// Registration is returned by the ACME server after the registration
+// The client implementation should save this registration somewhere.
+type Registration struct {
+	Resource       string          `json:"resource,omitempty"`
+	ID             int             `json:"id"`
+	Key            jose.JsonWebKey `json:"key"`
+	Contact        []string        `json:"contact"`
+	Agreement      string          `json:"agreement,omitempty"`
+	Authorizations string          `json:"authorizations,omitempty"`
+	Certificates   string          `json:"certificates,omitempty"`
+}
+
+// RegistrationResource represents all important informations about a registration
+// of which the client needs to keep track itself.
+type RegistrationResource struct {
+	Body        Registration `json:"body,omitempty"`
+	URI         string       `json:"uri,omitempty"`
+	NewAuthzURL string       `json:"new_authzr_uri,omitempty"`
+	TosURL      string       `json:"terms_of_service,omitempty"`
+}
+
+type authorizationResource struct {
+	Body       authorization
+	Domain     string
+	NewCertURL string
+	AuthURL    string
+}
+
+type authorization struct {
+	Resource     string      `json:"resource,omitempty"`
+	Identifier   identifier  `json:"identifier"`
+	Status       string      `json:"status,omitempty"`
+	Expires      time.Time   `json:"expires,omitempty"`
+	Challenges   []challenge `json:"challenges,omitempty"`
+	Combinations [][]int     `json:"combinations,omitempty"`
+}
+
+type identifier struct {
+	Type  string `json:"type"`
+	Value string `json:"value"`
+}
+
+type validationRecord struct {
+	URI               string   `json:"url,omitempty"`
+	Hostname          string   `json:"hostname,omitempty"`
+	Port              string   `json:"port,omitempty"`
+	ResolvedAddresses []string `json:"addressesResolved,omitempty"`
+	UsedAddress       string   `json:"addressUsed,omitempty"`
+}
+
+type challenge struct {
+	Resource          string             `json:"resource,omitempty"`
+	Type              Challenge          `json:"type,omitempty"`
+	Status            string             `json:"status,omitempty"`
+	URI               string             `json:"uri,omitempty"`
+	Token             string             `json:"token,omitempty"`
+	KeyAuthorization  string             `json:"keyAuthorization,omitempty"`
+	TLS               bool               `json:"tls,omitempty"`
+	Iterations        int                `json:"n,omitempty"`
+	Error             RemoteError        `json:"error,omitempty"`
+	ValidationRecords []validationRecord `json:"validationRecord,omitempty"`
+}
+
+type csrMessage struct {
+	Resource       string   `json:"resource,omitempty"`
+	Csr            string   `json:"csr"`
+	Authorizations []string `json:"authorizations"`
+}
+
+type revokeCertMessage struct {
+	Resource    string `json:"resource"`
+	Certificate string `json:"certificate"`
+}
+
+// CertificateResource represents a CA issued certificate.
+// PrivateKey, Certificate and IssuerCertificate are all
+// already PEM encoded and can be directly written to disk.
+// Certificate may be a certificate bundle, depending on the
+// options supplied to create it.
+type CertificateResource struct {
+	Domain            string `json:"domain"`
+	CertURL           string `json:"certUrl"`
+	CertStableURL     string `json:"certStableUrl"`
+	AccountRef        string `json:"accountRef,omitempty"`
+	PrivateKey        []byte `json:"-"`
+	Certificate       []byte `json:"-"`
+	IssuerCertificate []byte `json:"-"`
+	CSR               []byte `json:"-"`
+}

vendor/github.com/xenolf/lego/acme/pop_challenge.go

@@ -0,0 +1 @@
+package acme

vendor/github.com/xenolf/lego/acme/provider.go

@@ -0,0 +1,28 @@
+package acme
+
+import "time"
+
+// ChallengeProvider enables implementing a custom challenge
+// provider. Present presents the solution to a challenge available to
+// be solved. CleanUp will be called by the challenge if Present ends
+// in a non-error state.
+type ChallengeProvider interface {
+	Present(domain, token, keyAuth string) error
+	CleanUp(domain, token, keyAuth string) error
+}
+
+// ChallengeProviderTimeout allows for implementing a
+// ChallengeProvider where an unusually long timeout is required when
+// waiting for an ACME challenge to be satisfied, such as when
+// checking for DNS record progagation. If an implementor of a
+// ChallengeProvider provides a Timeout method, then the return values
+// of the Timeout method will be used when appropriate by the acme
+// package. The interval value is the time between checks.
+//
+// The default values used for timeout and interval are 60 seconds and
+// 2 seconds respectively. These are used when no Timeout method is
+// defined for the ChallengeProvider.
+type ChallengeProviderTimeout interface {
+	ChallengeProvider
+	Timeout() (timeout, interval time.Duration)
+}

vendor/github.com/xenolf/lego/acme/tls_sni_challenge.go

@@ -0,0 +1,67 @@
+package acme
+
+import (
+	"crypto/rsa"
+	"crypto/sha256"
+	"crypto/tls"
+	"encoding/hex"
+	"fmt"
+	"log"
+)
+
+type tlsSNIChallenge struct {
+	jws      *jws
+	validate validateFunc
+	provider ChallengeProvider
+}
+
+func (t *tlsSNIChallenge) Solve(chlng challenge, domain string) error {
+	// FIXME: https://github.com/ietf-wg-acme/acme/pull/22
+	// Currently we implement this challenge to track boulder, not the current spec!
+
+	logf("[INFO][%s] acme: Trying to solve TLS-SNI-01", domain)
+
+	// Generate the Key Authorization for the challenge
+	keyAuth, err := getKeyAuthorization(chlng.Token, t.jws.privKey)
+	if err != nil {
+		return err
+	}
+
+	err = t.provider.Present(domain, chlng.Token, keyAuth)
+	if err != nil {
+		return fmt.Errorf("[%s] error presenting token: %v", domain, err)
+	}
+	defer func() {
+		err := t.provider.CleanUp(domain, chlng.Token, keyAuth)
+		if err != nil {
+			log.Printf("[%s] error cleaning up: %v", domain, err)
+		}
+	}()
+	return t.validate(t.jws, domain, chlng.URI, challenge{Resource: "challenge", Type: chlng.Type, Token: chlng.Token, KeyAuthorization: keyAuth})
+}
+
+// TLSSNI01ChallengeCert returns a certificate and target domain for the `tls-sni-01` challenge
+func TLSSNI01ChallengeCert(keyAuth string) (tls.Certificate, string, error) {
+	// generate a new RSA key for the certificates
+	tempPrivKey, err := generatePrivateKey(RSA2048)
+	if err != nil {
+		return tls.Certificate{}, "", err
+	}
+	rsaPrivKey := tempPrivKey.(*rsa.PrivateKey)
+	rsaPrivPEM := pemEncode(rsaPrivKey)
+
+	zBytes := sha256.Sum256([]byte(keyAuth))
+	z := hex.EncodeToString(zBytes[:sha256.Size])
+	domain := fmt.Sprintf("%s.%s.acme.invalid", z[:32], z[32:])
+	tempCertPEM, err := generatePemCert(rsaPrivKey, domain)
+	if err != nil {
+		return tls.Certificate{}, "", err
+	}
+
+	certificate, err := tls.X509KeyPair(tempCertPEM, rsaPrivPEM)
+	if err != nil {
+		return tls.Certificate{}, "", err
+	}
+
+	return certificate, domain, nil
+}

vendor/github.com/xenolf/lego/acme/tls_sni_challenge_server.go

@@ -0,0 +1,62 @@
+package acme
+
+import (
+	"crypto/tls"
+	"fmt"
+	"net"
+	"net/http"
+)
+
+// TLSProviderServer implements ChallengeProvider for `TLS-SNI-01` challenge
+// It may be instantiated without using the NewTLSProviderServer function if
+// you want only to use the default values.
+type TLSProviderServer struct {
+	iface    string
+	port     string
+	done     chan bool
+	listener net.Listener
+}
+
+// NewTLSProviderServer creates a new TLSProviderServer on the selected interface and port.
+// Setting iface and / or port to an empty string will make the server fall back to
+// the "any" interface and port 443 respectively.
+func NewTLSProviderServer(iface, port string) *TLSProviderServer {
+	return &TLSProviderServer{iface: iface, port: port}
+}
+
+// Present makes the keyAuth available as a cert
+func (s *TLSProviderServer) Present(domain, token, keyAuth string) error {
+	if s.port == "" {
+		s.port = "443"
+	}
+
+	cert, _, err := TLSSNI01ChallengeCert(keyAuth)
+	if err != nil {
+		return err
+	}
+
+	tlsConf := new(tls.Config)
+	tlsConf.Certificates = []tls.Certificate{cert}
+
+	s.listener, err = tls.Listen("tcp", net.JoinHostPort(s.iface, s.port), tlsConf)
+	if err != nil {
+		return fmt.Errorf("Could not start HTTPS server for challenge -> %v", err)
+	}
+
+	s.done = make(chan bool)
+	go func() {
+		http.Serve(s.listener, nil)
+		s.done <- true
+	}()
+	return nil
+}
+
+// CleanUp closes the HTTP server.
+func (s *TLSProviderServer) CleanUp(domain, token, keyAuth string) error {
+	if s.listener == nil {
+		return nil
+	}
+	s.listener.Close()
+	<-s.done
+	return nil
+}

vendor/github.com/xenolf/lego/acme/utils.go

@@ -0,0 +1,29 @@
+package acme
+
+import (
+	"fmt"
+	"time"
+)
+
+// WaitFor polls the given function 'f', once every 'interval', up to 'timeout'.
+func WaitFor(timeout, interval time.Duration, f func() (bool, error)) error {
+	var lastErr string
+	timeup := time.After(timeout)
+	for {
+		select {
+		case <-timeup:
+			return fmt.Errorf("Time limit exceeded. Last error: %s", lastErr)
+		default:
+		}
+
+		stop, err := f()
+		if stop {
+			return nil
+		}
+		if err != nil {
+			lastErr = err.Error()
+		}
+
+		time.Sleep(interval)
+	}
+}

vendor/github.com/xenolf/lego/cli.go

@@ -0,0 +1,231 @@
+// Let's Encrypt client to go!
+// CLI application for generating Let's Encrypt certificates using the ACME package.
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path"
+	"strings"
+	"text/tabwriter"
+
+	"github.com/urfave/cli"
+	"github.com/xenolf/lego/acme"
+)
+
+// Logger is used to log errors; if nil, the default log.Logger is used.
+var Logger *log.Logger
+
+// logger is an helper function to retrieve the available logger
+func logger() *log.Logger {
+	if Logger == nil {
+		Logger = log.New(os.Stderr, "", log.LstdFlags)
+	}
+	return Logger
+}
+
+var gittag string
+
+func main() {
+	app := cli.NewApp()
+	app.Name = "lego"
+	app.Usage = "Let's Encrypt client written in Go"
+
+	version := "0.3.1"
+	if strings.HasPrefix(gittag, "v") {
+		version = gittag
+	}
+
+	app.Version = version
+
+	acme.UserAgent = "lego/" + app.Version
+
+	defaultPath := ""
+	cwd, err := os.Getwd()
+	if err == nil {
+		defaultPath = path.Join(cwd, ".lego")
+	}
+
+	app.Before = func(c *cli.Context) error {
+		if c.GlobalString("path") == "" {
+			logger().Fatal("Could not determine current working directory. Please pass --path.")
+		}
+		return nil
+	}
+
+	app.Commands = []cli.Command{
+		{
+			Name:   "run",
+			Usage:  "Register an account, then create and install a certificate",
+			Action: run,
+			Flags: []cli.Flag{
+				cli.BoolFlag{
+					Name:  "no-bundle",
+					Usage: "Do not create a certificate bundle by adding the issuers certificate to the new certificate.",
+				},
+				cli.BoolFlag{
+					Name:  "must-staple",
+					Usage: "Include the OCSP must staple TLS extension in the CSR and generated certificate. Only works if the CSR is generated by lego.",
+				},
+			},
+		},
+		{
+			Name:   "revoke",
+			Usage:  "Revoke a certificate",
+			Action: revoke,
+		},
+		{
+			Name:   "renew",
+			Usage:  "Renew a certificate",
+			Action: renew,
+			Flags: []cli.Flag{
+				cli.IntFlag{
+					Name:  "days",
+					Value: 0,
+					Usage: "The number of days left on a certificate to renew it.",
+				},
+				cli.BoolFlag{
+					Name:  "reuse-key",
+					Usage: "Used to indicate you want to reuse your current private key for the new certificate.",
+				},
+				cli.BoolFlag{
+					Name:  "no-bundle",
+					Usage: "Do not create a certificate bundle by adding the issuers certificate to the new certificate.",
+				},
+				cli.BoolFlag{
+					Name:  "must-staple",
+					Usage: "Include the OCSP must staple TLS extension in the CSR and generated certificate. Only works if the CSR is generated by lego.",
+				},
+			},
+		},
+		{
+			Name:   "dnshelp",
+			Usage:  "Shows additional help for the --dns global option",
+			Action: dnshelp,
+		},
+	}
+
+	app.Flags = []cli.Flag{
+		cli.StringSliceFlag{
+			Name:  "domains, d",
+			Usage: "Add domains to the process",
+		},
+		cli.StringFlag{
+			Name:  "csr, c",
+			Usage: "Certificate signing request filename, if an external CSR is to be used",
+		},
+		cli.StringFlag{
+			Name:  "server, s",
+			Value: "https://acme-v01.api.letsencrypt.org/directory",
+			Usage: "CA hostname (and optionally :port). The server certificate must be trusted in order to avoid further modifications to the client.",
+		},
+		cli.StringFlag{
+			Name:  "email, m",
+			Usage: "Email used for registration and recovery contact.",
+		},
+		cli.BoolFlag{
+			Name:  "accept-tos, a",
+			Usage: "By setting this flag to true you indicate that you accept the current Let's Encrypt terms of service.",
+		},
+		cli.StringFlag{
+			Name:  "key-type, k",
+			Value: "rsa2048",
+			Usage: "Key type to use for private keys. Supported: rsa2048, rsa4096, rsa8192, ec256, ec384",
+		},
+		cli.StringFlag{
+			Name:  "path",
+			Usage: "Directory to use for storing the data",
+			Value: defaultPath,
+		},
+		cli.StringSliceFlag{
+			Name:  "exclude, x",
+			Usage: "Explicitly disallow solvers by name from being used. Solvers: \"http-01\", \"tls-sni-01\".",
+		},
+		cli.StringFlag{
+			Name:  "webroot",
+			Usage: "Set the webroot folder to use for HTTP based challenges to write directly in a file in .well-known/acme-challenge",
+		},
+		cli.StringSliceFlag{
+			Name:  "memcached-host",
+			Usage: "Set the memcached host(s) to use for HTTP based challenges. Challenges will be written to all specified hosts.",
+		},
+		cli.StringFlag{
+			Name:  "http",
+			Usage: "Set the port and interface to use for HTTP based challenges to listen on. Supported: interface:port or :port",
+		},
+		cli.StringFlag{
+			Name:  "tls",
+			Usage: "Set the port and interface to use for TLS based challenges to listen on. Supported: interface:port or :port",
+		},
+		cli.StringFlag{
+			Name:  "dns",
+			Usage: "Solve a DNS challenge using the specified provider. Disables all other challenges. Run 'lego dnshelp' for help on usage.",
+		},
+		cli.IntFlag{
+			Name:  "http-timeout",
+			Usage: "Set the HTTP timeout value to a specific value in seconds. The default is 10 seconds.",
+		},
+		cli.IntFlag{
+			Name:  "dns-timeout",
+			Usage: "Set the DNS timeout value to a specific value in seconds. The default is 10 seconds.",
+		},
+		cli.StringSliceFlag{
+			Name:  "dns-resolvers",
+			Usage: "Set the resolvers to use for performing recursive DNS queries. Supported: host:port. The default is to use Google's DNS resolvers.",
+		},
+		cli.BoolFlag{
+			Name:  "pem",
+			Usage: "Generate a .pem file by concatanating the .key and .crt files together.",
+		},
+	}
+
+	err = app.Run(os.Args)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func dnshelp(c *cli.Context) error {
+	fmt.Printf(
+		`Credentials for DNS providers must be passed through environment variables.
+
+Here is an example bash command using the CloudFlare DNS provider:
+
+  $ CLOUDFLARE_EMAIL=foo@bar.com \
+    CLOUDFLARE_API_KEY=b9841238feb177a84330febba8a83208921177bffe733 \
+    lego --dns cloudflare --domains www.example.com --email me@bar.com run
+
+`)
+
+	w := tabwriter.NewWriter(os.Stdout, 0, 8, 1, '\t', 0)
+	fmt.Fprintln(w, "Valid providers and their associated credential environment variables:")
+	fmt.Fprintln(w)
+	fmt.Fprintln(w, "\tazure:\tAZURE_CLIENT_ID, AZURE_CLIENT_SECRET, AZURE_SUBSCRIPTION_ID, AZURE_TENANT_ID, AZURE_RESOURCE_GROUP")
+	fmt.Fprintln(w, "\tauroradns:\tAURORA_USER_ID, AURORA_KEY, AURORA_ENDPOINT")
+	fmt.Fprintln(w, "\tcloudflare:\tCLOUDFLARE_EMAIL, CLOUDFLARE_API_KEY")
+	fmt.Fprintln(w, "\tdigitalocean:\tDO_AUTH_TOKEN")
+	fmt.Fprintln(w, "\tdnsimple:\tDNSIMPLE_EMAIL, DNSIMPLE_API_KEY")
+	fmt.Fprintln(w, "\tdnsmadeeasy:\tDNSMADEEASY_API_KEY, DNSMADEEASY_API_SECRET")
+	fmt.Fprintln(w, "\texoscale:\tEXOSCALE_API_KEY, EXOSCALE_API_SECRET, EXOSCALE_ENDPOINT")
+	fmt.Fprintln(w, "\tgandi:\tGANDI_API_KEY")
+	fmt.Fprintln(w, "\tgcloud:\tGCE_PROJECT")
+	fmt.Fprintln(w, "\tlinode:\tLINODE_API_KEY")
+	fmt.Fprintln(w, "\tmanual:\tnone")
+	fmt.Fprintln(w, "\tnamecheap:\tNAMECHEAP_API_USER, NAMECHEAP_API_KEY")
+	fmt.Fprintln(w, "\trackspace:\tRACKSPACE_USER, RACKSPACE_API_KEY")
+	fmt.Fprintln(w, "\trfc2136:\tRFC2136_TSIG_KEY, RFC2136_TSIG_SECRET,\n\t\tRFC2136_TSIG_ALGORITHM, RFC2136_NAMESERVER")
+	fmt.Fprintln(w, "\troute53:\tAWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_REGION")
+	fmt.Fprintln(w, "\tdyn:\tDYN_CUSTOMER_NAME, DYN_USER_NAME, DYN_PASSWORD")
+	fmt.Fprintln(w, "\tvultr:\tVULTR_API_KEY")
+	fmt.Fprintln(w, "\tovh:\tOVH_ENDPOINT, OVH_APPLICATION_KEY, OVH_APPLICATION_SECRET, OVH_CONSUMER_KEY")
+	fmt.Fprintln(w, "\tpdns:\tPDNS_API_KEY, PDNS_API_URL")
+	fmt.Fprintln(w, "\tdnspod:\tDNSPOD_API_KEY")
+	w.Flush()
+
+	fmt.Println(`
+For a more detailed explanation of a DNS provider's credential variables,
+please consult their online documentation.`)
+
+	return nil
+}

vendor/github.com/xenolf/lego/cli_handlers.go

@@ -0,0 +1,418 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/x509"
+	"encoding/json"
+	"encoding/pem"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path"
+	"strings"
+	"time"
+
+	"github.com/urfave/cli"
+	"github.com/xenolf/lego/acme"
+	"github.com/xenolf/lego/providers/dns"
+	"github.com/xenolf/lego/providers/http/memcached"
+	"github.com/xenolf/lego/providers/http/webroot"
+)
+
+func checkFolder(path string) error {
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return os.MkdirAll(path, 0700)
+	}
+	return nil
+}
+
+func setup(c *cli.Context) (*Configuration, *Account, *acme.Client) {
+
+	if c.GlobalIsSet("http-timeout") {
+		acme.HTTPClient = http.Client{Timeout: time.Duration(c.GlobalInt("http-timeout")) * time.Second}
+	}
+
+	if c.GlobalIsSet("dns-timeout") {
+		acme.DNSTimeout = time.Duration(c.GlobalInt("dns-timeout")) * time.Second
+	}
+
+	if len(c.GlobalStringSlice("dns-resolvers")) > 0 {
+		resolvers := []string{}
+		for _, resolver := range c.GlobalStringSlice("dns-resolvers") {
+			if !strings.Contains(resolver, ":") {
+				resolver += ":53"
+			}
+			resolvers = append(resolvers, resolver)
+		}
+		acme.RecursiveNameservers = resolvers
+	}
+
+	err := checkFolder(c.GlobalString("path"))
+	if err != nil {
+		logger().Fatalf("Could not check/create path: %s", err.Error())
+	}
+
+	conf := NewConfiguration(c)
+	if len(c.GlobalString("email")) == 0 {
+		logger().Fatal("You have to pass an account (email address) to the program using --email or -m")
+	}
+
+	//TODO: move to account struct? Currently MUST pass email.
+	acc := NewAccount(c.GlobalString("email"), conf)
+
+	keyType, err := conf.KeyType()
+	if err != nil {
+		logger().Fatal(err.Error())
+	}
+
+	client, err := acme.NewClient(c.GlobalString("server"), acc, keyType)
+	if err != nil {
+		logger().Fatalf("Could not create client: %s", err.Error())
+	}
+
+	if len(c.GlobalStringSlice("exclude")) > 0 {
+		client.ExcludeChallenges(conf.ExcludedSolvers())
+	}
+
+	if c.GlobalIsSet("webroot") {
+		provider, err := webroot.NewHTTPProvider(c.GlobalString("webroot"))
+		if err != nil {
+			logger().Fatal(err)
+		}
+
+		client.SetChallengeProvider(acme.HTTP01, provider)
+
+		// --webroot=foo indicates that the user specifically want to do a HTTP challenge
+		// infer that the user also wants to exclude all other challenges
+		client.ExcludeChallenges([]acme.Challenge{acme.DNS01, acme.TLSSNI01})
+	}
+	if c.GlobalIsSet("memcached-host") {
+		provider, err := memcached.NewMemcachedProvider(c.GlobalStringSlice("memcached-host"))
+		if err != nil {
+			logger().Fatal(err)
+		}
+
+		client.SetChallengeProvider(acme.HTTP01, provider)
+
+		// --memcached-host=foo:11211 indicates that the user specifically want to do a HTTP challenge
+		// infer that the user also wants to exclude all other challenges
+		client.ExcludeChallenges([]acme.Challenge{acme.DNS01, acme.TLSSNI01})
+	}
+	if c.GlobalIsSet("http") {
+		if strings.Index(c.GlobalString("http"), ":") == -1 {
+			logger().Fatalf("The --http switch only accepts interface:port or :port for its argument.")
+		}
+		client.SetHTTPAddress(c.GlobalString("http"))
+	}
+
+	if c.GlobalIsSet("tls") {
+		if strings.Index(c.GlobalString("tls"), ":") == -1 {
+			logger().Fatalf("The --tls switch only accepts interface:port or :port for its argument.")
+		}
+		client.SetTLSAddress(c.GlobalString("tls"))
+	}
+
+	if c.GlobalIsSet("dns") {
+    provider, err := dns.NewDNSChallengeProviderByName(c.GlobalString("dns"))
+		if err != nil {
+			logger().Fatal(err)
+		}
+
+		client.SetChallengeProvider(acme.DNS01, provider)
+
+		// --dns=foo indicates that the user specifically want to do a DNS challenge
+		// infer that the user also wants to exclude all other challenges
+		client.ExcludeChallenges([]acme.Challenge{acme.HTTP01, acme.TLSSNI01})
+	}
+
+	return conf, acc, client
+}
+
+func saveCertRes(certRes acme.CertificateResource, conf *Configuration) {
+	// We store the certificate, private key and metadata in different files
+	// as web servers would not be able to work with a combined file.
+	certOut := path.Join(conf.CertPath(), certRes.Domain+".crt")
+	privOut := path.Join(conf.CertPath(), certRes.Domain+".key")
+	pemOut := path.Join(conf.CertPath(), certRes.Domain+".pem")
+	metaOut := path.Join(conf.CertPath(), certRes.Domain+".json")
+	issuerOut := path.Join(conf.CertPath(), certRes.Domain+".issuer.crt")
+
+	err := ioutil.WriteFile(certOut, certRes.Certificate, 0600)
+	if err != nil {
+		logger().Fatalf("Unable to save Certificate for domain %s\n\t%s", certRes.Domain, err.Error())
+	}
+
+	if certRes.IssuerCertificate != nil {
+		err = ioutil.WriteFile(issuerOut, certRes.IssuerCertificate, 0600)
+		if err != nil {
+			logger().Fatalf("Unable to save IssuerCertificate for domain %s\n\t%s", certRes.Domain, err.Error())
+		}
+	}
+
+	if certRes.PrivateKey != nil {
+		// if we were given a CSR, we don't know the private key
+		err = ioutil.WriteFile(privOut, certRes.PrivateKey, 0600)
+		if err != nil {
+			logger().Fatalf("Unable to save PrivateKey for domain %s\n\t%s", certRes.Domain, err.Error())
+		}
+
+		if conf.context.GlobalBool("pem") {
+			err = ioutil.WriteFile(pemOut, bytes.Join([][]byte{certRes.Certificate, certRes.PrivateKey}, nil), 0600)
+			if err != nil {
+				logger().Fatalf("Unable to save Certificate and PrivateKey in .pem for domain %s\n\t%s", certRes.Domain, err.Error())
+			}
+		}
+
+	} else if conf.context.GlobalBool("pem") {
+		// we don't have the private key; can't write the .pem file
+		logger().Fatalf("Unable to save pem without private key for domain %s\n\t%s; are you using a CSR?", certRes.Domain, err.Error())
+	}
+
+	jsonBytes, err := json.MarshalIndent(certRes, "", "\t")
+	if err != nil {
+		logger().Fatalf("Unable to marshal CertResource for domain %s\n\t%s", certRes.Domain, err.Error())
+	}
+
+	err = ioutil.WriteFile(metaOut, jsonBytes, 0600)
+	if err != nil {
+		logger().Fatalf("Unable to save CertResource for domain %s\n\t%s", certRes.Domain, err.Error())
+	}
+}
+
+func handleTOS(c *cli.Context, client *acme.Client, acc *Account) {
+	// Check for a global accept override
+	if c.GlobalBool("accept-tos") {
+		err := client.AgreeToTOS()
+		if err != nil {
+			logger().Fatalf("Could not agree to TOS: %s", err.Error())
+		}
+
+		acc.Save()
+		return
+	}
+
+	reader := bufio.NewReader(os.Stdin)
+	logger().Printf("Please review the TOS at %s", acc.Registration.TosURL)
+
+	for {
+		logger().Println("Do you accept the TOS? Y/n")
+		text, err := reader.ReadString('\n')
+		if err != nil {
+			logger().Fatalf("Could not read from console: %s", err.Error())
+		}
+
+		text = strings.Trim(text, "\r\n")
+
+		if text == "n" {
+			logger().Fatal("You did not accept the TOS. Unable to proceed.")
+		}
+
+		if text == "Y" || text == "y" || text == "" {
+			err = client.AgreeToTOS()
+			if err != nil {
+				logger().Fatalf("Could not agree to TOS: %s", err.Error())
+			}
+			acc.Save()
+			break
+		}
+
+		logger().Println("Your input was invalid. Please answer with one of Y/y, n or by pressing enter.")
+	}
+}
+
+func readCSRFile(filename string) (*x509.CertificateRequest, error) {
+	bytes, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+	raw := bytes
+
+	// see if we can find a PEM-encoded CSR
+	var p *pem.Block
+	rest := bytes
+	for {
+		// decode a PEM block
+		p, rest = pem.Decode(rest)
+
+		// did we fail?
+		if p == nil {
+			break
+		}
+
+		// did we get a CSR?
+		if p.Type == "CERTIFICATE REQUEST" {
+			raw = p.Bytes
+		}
+	}
+
+	// no PEM-encoded CSR
+	// assume we were given a DER-encoded ASN.1 CSR
+	// (if this assumption is wrong, parsing these bytes will fail)
+	return x509.ParseCertificateRequest(raw)
+}
+
+func run(c *cli.Context) error {
+	conf, acc, client := setup(c)
+	if acc.Registration == nil {
+		reg, err := client.Register()
+		if err != nil {
+			logger().Fatalf("Could not complete registration\n\t%s", err.Error())
+		}
+
+		acc.Registration = reg
+		acc.Save()
+
+		logger().Print("!!!! HEADS UP !!!!")
+		logger().Printf(`
+		Your account credentials have been saved in your Let's Encrypt
+		configuration directory at "%s".
+		You should make a secure backup	of this folder now. This
+		configuration directory will also contain certificates and
+		private keys obtained from Let's Encrypt so making regular
+		backups of this folder is ideal.`, conf.AccountPath(c.GlobalString("email")))
+
+	}
+
+	// If the agreement URL is empty, the account still needs to accept the LE TOS.
+	if acc.Registration.Body.Agreement == "" {
+		handleTOS(c, client, acc)
+	}
+
+	// we require either domains or csr, but not both
+	hasDomains := len(c.GlobalStringSlice("domains")) > 0
+	hasCsr := len(c.GlobalString("csr")) > 0
+	if hasDomains && hasCsr {
+		logger().Fatal("Please specify either --domains/-d or --csr/-c, but not both")
+	}
+	if !hasDomains && !hasCsr {
+		logger().Fatal("Please specify --domains/-d (or --csr/-c if you already have a CSR)")
+	}
+
+	var cert acme.CertificateResource
+	var failures map[string]error
+
+	if hasDomains {
+		// obtain a certificate, generating a new private key
+		cert, failures = client.ObtainCertificate(c.GlobalStringSlice("domains"), !c.Bool("no-bundle"), nil, c.Bool("must-staple"))
+	} else {
+		// read the CSR
+		csr, err := readCSRFile(c.GlobalString("csr"))
+		if err != nil {
+			// we couldn't read the CSR
+			failures = map[string]error{"csr": err}
+		} else {
+			// obtain a certificate for this CSR
+			cert, failures = client.ObtainCertificateForCSR(*csr, !c.Bool("no-bundle"))
+		}
+	}
+
+	if len(failures) > 0 {
+		for k, v := range failures {
+			logger().Printf("[%s] Could not obtain certificates\n\t%s", k, v.Error())
+		}
+
+		// Make sure to return a non-zero exit code if ObtainSANCertificate
+		// returned at least one error. Due to us not returning partial
+		// certificate we can just exit here instead of at the end.
+		os.Exit(1)
+	}
+
+	err := checkFolder(conf.CertPath())
+	if err != nil {
+		logger().Fatalf("Could not check/create path: %s", err.Error())
+	}
+
+	saveCertRes(cert, conf)
+
+	return nil
+}
+
+func revoke(c *cli.Context) error {
+
+	conf, _, client := setup(c)
+
+	err := checkFolder(conf.CertPath())
+	if err != nil {
+		logger().Fatalf("Could not check/create path: %s", err.Error())
+	}
+
+	for _, domain := range c.GlobalStringSlice("domains") {
+		logger().Printf("Trying to revoke certificate for domain %s", domain)
+
+		certPath := path.Join(conf.CertPath(), domain+".crt")
+		certBytes, err := ioutil.ReadFile(certPath)
+
+		err = client.RevokeCertificate(certBytes)
+		if err != nil {
+			logger().Fatalf("Error while revoking the certificate for domain %s\n\t%s", domain, err.Error())
+		} else {
+			logger().Print("Certificate was revoked.")
+		}
+	}
+
+	return nil
+}
+
+func renew(c *cli.Context) error {
+	conf, _, client := setup(c)
+
+	if len(c.GlobalStringSlice("domains")) <= 0 {
+		logger().Fatal("Please specify at least one domain.")
+	}
+
+	domain := c.GlobalStringSlice("domains")[0]
+
+	// load the cert resource from files.
+	// We store the certificate, private key and metadata in different files
+	// as web servers would not be able to work with a combined file.
+	certPath := path.Join(conf.CertPath(), domain+".crt")
+	privPath := path.Join(conf.CertPath(), domain+".key")
+	metaPath := path.Join(conf.CertPath(), domain+".json")
+
+	certBytes, err := ioutil.ReadFile(certPath)
+	if err != nil {
+		logger().Fatalf("Error while loading the certificate for domain %s\n\t%s", domain, err.Error())
+	}
+
+	if c.IsSet("days") {
+		expTime, err := acme.GetPEMCertExpiration(certBytes)
+		if err != nil {
+			logger().Printf("Could not get Certification expiration for domain %s", domain)
+		}
+
+		if int(expTime.Sub(time.Now()).Hours()/24.0) > c.Int("days") {
+			return nil
+		}
+	}
+
+	metaBytes, err := ioutil.ReadFile(metaPath)
+	if err != nil {
+		logger().Fatalf("Error while loading the meta data for domain %s\n\t%s", domain, err.Error())
+	}
+
+	var certRes acme.CertificateResource
+	err = json.Unmarshal(metaBytes, &certRes)
+	if err != nil {
+		logger().Fatalf("Error while marshalling the meta data for domain %s\n\t%s", domain, err.Error())
+	}
+
+	if c.Bool("reuse-key") {
+		keyBytes, err := ioutil.ReadFile(privPath)
+		if err != nil {
+			logger().Fatalf("Error while loading the private key for domain %s\n\t%s", domain, err.Error())
+		}
+		certRes.PrivateKey = keyBytes
+	}
+
+	certRes.Certificate = certBytes
+
+	newCert, err := client.RenewCertificate(certRes, !c.Bool("no-bundle"), c.Bool("must-staple"))
+	if err != nil {
+		logger().Fatalf("%s", err.Error())
+	}
+
+	saveCertRes(newCert, conf)
+
+	return nil
+}

vendor/github.com/xenolf/lego/configuration.go

@@ -0,0 +1,76 @@
+package main
+
+import (
+	"fmt"
+	"net/url"
+	"os"
+	"path"
+	"strings"
+
+	"github.com/urfave/cli"
+	"github.com/xenolf/lego/acme"
+)
+
+// Configuration type from CLI and config files.
+type Configuration struct {
+	context *cli.Context
+}
+
+// NewConfiguration creates a new configuration from CLI data.
+func NewConfiguration(c *cli.Context) *Configuration {
+	return &Configuration{context: c}
+}
+
+// KeyType the type from which private keys should be generated
+func (c *Configuration) KeyType() (acme.KeyType, error) {
+	switch strings.ToUpper(c.context.GlobalString("key-type")) {
+	case "RSA2048":
+		return acme.RSA2048, nil
+	case "RSA4096":
+		return acme.RSA4096, nil
+	case "RSA8192":
+		return acme.RSA8192, nil
+	case "EC256":
+		return acme.EC256, nil
+	case "EC384":
+		return acme.EC384, nil
+	}
+
+	return "", fmt.Errorf("Unsupported KeyType: %s", c.context.GlobalString("key-type"))
+}
+
+// ExcludedSolvers is a list of solvers that are to be excluded.
+func (c *Configuration) ExcludedSolvers() (cc []acme.Challenge) {
+	for _, s := range c.context.GlobalStringSlice("exclude") {
+		cc = append(cc, acme.Challenge(s))
+	}
+	return
+}
+
+// ServerPath returns the OS dependent path to the data for a specific CA
+func (c *Configuration) ServerPath() string {
+	srv, _ := url.Parse(c.context.GlobalString("server"))
+	srvStr := strings.Replace(srv.Host, ":", "_", -1)
+	return strings.Replace(srvStr, "/", string(os.PathSeparator), -1)
+}
+
+// CertPath gets the path for certificates.
+func (c *Configuration) CertPath() string {
+	return path.Join(c.context.GlobalString("path"), "certificates")
+}
+
+// AccountsPath returns the OS dependent path to the
+// local accounts for a specific CA
+func (c *Configuration) AccountsPath() string {
+	return path.Join(c.context.GlobalString("path"), "accounts", c.ServerPath())
+}
+
+// AccountPath returns the OS dependent path to a particular account
+func (c *Configuration) AccountPath(acc string) string {
+	return path.Join(c.AccountsPath(), acc)
+}
+
+// AccountKeysPath returns the OS dependent path to the keys of a particular account
+func (c *Configuration) AccountKeysPath(acc string) string {
+	return path.Join(c.AccountPath(acc), "keys")
+}

vendor/github.com/xenolf/lego/crypto.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"io/ioutil"
+	"os"
+)
+
+func generatePrivateKey(file string) (crypto.PrivateKey, error) {
+
+	privateKey, err := ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
+	if err != nil {
+		return nil, err
+	}
+
+	keyBytes, err := x509.MarshalECPrivateKey(privateKey)
+	if err != nil {
+		return nil, err
+	}
+
+	pemKey := pem.Block{Type: "EC PRIVATE KEY", Bytes: keyBytes}
+
+	certOut, err := os.Create(file)
+	if err != nil {
+		return nil, err
+	}
+
+	pem.Encode(certOut, &pemKey)
+	certOut.Close()
+
+	return privateKey, nil
+}
+
+func loadPrivateKey(file string) (crypto.PrivateKey, error) {
+	keyBytes, err := ioutil.ReadFile(file)
+	if err != nil {
+		return nil, err
+	}
+
+	keyBlock, _ := pem.Decode(keyBytes)
+
+	switch keyBlock.Type {
+	case "RSA PRIVATE KEY":
+		return x509.ParsePKCS1PrivateKey(keyBlock.Bytes)
+	case "EC PRIVATE KEY":
+		return x509.ParseECPrivateKey(keyBlock.Bytes)
+	}
+
+	return nil, errors.New("Unknown private key type.")
+}

vendor/github.com/xenolf/lego/providers/dns/auroradns/auroradns.go

@@ -0,0 +1,141 @@
+package auroradns
+
+import (
+	"fmt"
+	"github.com/edeckers/auroradnsclient"
+	"github.com/edeckers/auroradnsclient/records"
+	"github.com/edeckers/auroradnsclient/zones"
+	"github.com/xenolf/lego/acme"
+	"os"
+	"sync"
+)
+
+// DNSProvider describes a provider for AuroraDNS
+type DNSProvider struct {
+	recordIDs   map[string]string
+	recordIDsMu sync.Mutex
+	client      *auroradnsclient.AuroraDNSClient
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for AuroraDNS.
+// Credentials must be passed in the environment variables: AURORA_USER_ID
+// and AURORA_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	userID := os.Getenv("AURORA_USER_ID")
+	key := os.Getenv("AURORA_KEY")
+
+	endpoint := os.Getenv("AURORA_ENDPOINT")
+	if endpoint == "" {
+		endpoint = "https://api.auroradns.eu"
+	}
+
+	return NewDNSProviderCredentials(endpoint, userID, key)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for AuroraDNS.
+func NewDNSProviderCredentials(baseURL string, userID string, key string) (*DNSProvider, error) {
+	client, err := auroradnsclient.NewAuroraDNSClient(baseURL, userID, key)
+	if err != nil {
+		return nil, err
+	}
+
+	return &DNSProvider{
+		client:    client,
+		recordIDs: make(map[string]string),
+	}, nil
+}
+
+func (provider *DNSProvider) getZoneInformationByName(name string) (zones.ZoneRecord, error) {
+	zs, err := provider.client.GetZones()
+
+	if err != nil {
+		return zones.ZoneRecord{}, err
+	}
+
+	for _, element := range zs {
+		if element.Name == name {
+			return element, nil
+		}
+	}
+
+	return zones.ZoneRecord{}, fmt.Errorf("Could not find Zone record")
+}
+
+// Present creates a record with a secret
+func (provider *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return fmt.Errorf("Could not determine zone for domain: '%s'. %s", domain, err)
+	}
+
+	// 1. Aurora will happily create the TXT record when it is provided a fqdn,
+	//    but it will only appear in the control panel and will not be
+	//    propagated to DNS servers. Extract and use subdomain instead.
+	// 2. A trailing dot in the fqdn will cause Aurora to add a trailing dot to
+	//    the subdomain, resulting in _acme-challenge..<domain> rather
+	//    than _acme-challenge.<domain>
+
+	subdomain := fqdn[0 : len(fqdn)-len(authZone)-1]
+
+	authZone = acme.UnFqdn(authZone)
+
+	zoneRecord, err := provider.getZoneInformationByName(authZone)
+
+	reqData :=
+		records.CreateRecordRequest{
+			RecordType: "TXT",
+			Name:       subdomain,
+			Content:    value,
+			TTL:        300,
+		}
+
+	respData, err := provider.client.CreateRecord(zoneRecord.ID, reqData)
+	if err != nil {
+		return fmt.Errorf("Could not create record: '%s'.", err)
+	}
+
+	provider.recordIDsMu.Lock()
+	provider.recordIDs[fqdn] = respData.ID
+	provider.recordIDsMu.Unlock()
+
+	return nil
+}
+
+// CleanUp removes a given record that was generated by Present
+func (provider *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	provider.recordIDsMu.Lock()
+	recordID, ok := provider.recordIDs[fqdn]
+	provider.recordIDsMu.Unlock()
+
+	if !ok {
+		return fmt.Errorf("Unknown recordID for '%s'", fqdn)
+	}
+
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return fmt.Errorf("Could not determine zone for domain: '%s'. %s", domain, err)
+	}
+
+	authZone = acme.UnFqdn(authZone)
+
+	zoneRecord, err := provider.getZoneInformationByName(authZone)
+	if err != nil {
+		return err
+	}
+
+	_, err = provider.client.RemoveRecord(zoneRecord.ID, recordID)
+	if err != nil {
+		return err
+	}
+
+	provider.recordIDsMu.Lock()
+	delete(provider.recordIDs, fqdn)
+	provider.recordIDsMu.Unlock()
+
+	return nil
+}

vendor/github.com/xenolf/lego/providers/dns/azure/azure.go

@@ -0,0 +1,142 @@
+// Package azure implements a DNS provider for solving the DNS-01
+// challenge using azure DNS.
+// Azure doesn't like trailing dots on domain names, most of the acme code does.
+package azure
+
+import (
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/Azure/azure-sdk-for-go/arm/dns"
+
+	"github.com/Azure/go-autorest/autorest/azure"
+	"github.com/Azure/go-autorest/autorest/to"
+	"github.com/xenolf/lego/acme"
+	"strings"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface
+type DNSProvider struct {
+	clientId       string
+	clientSecret   string
+	subscriptionId string
+	tenantId       string
+	resourceGroup  string
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for azure.
+// Credentials must be passed in the environment variables: AZURE_CLIENT_ID,
+// AZURE_CLIENT_SECRET, AZURE_SUBSCRIPTION_ID, AZURE_TENANT_ID
+func NewDNSProvider() (*DNSProvider, error) {
+	clientId := os.Getenv("AZURE_CLIENT_ID")
+	clientSecret := os.Getenv("AZURE_CLIENT_SECRET")
+	subscriptionId := os.Getenv("AZURE_SUBSCRIPTION_ID")
+	tenantId := os.Getenv("AZURE_TENANT_ID")
+	resourceGroup := os.Getenv("AZURE_RESOURCE_GROUP")
+	return NewDNSProviderCredentials(clientId, clientSecret, subscriptionId, tenantId, resourceGroup)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for azure.
+func NewDNSProviderCredentials(clientId, clientSecret, subscriptionId, tenantId, resourceGroup string) (*DNSProvider, error) {
+	if clientId == "" || clientSecret == "" || subscriptionId == "" || tenantId == "" || resourceGroup == "" {
+		return nil, fmt.Errorf("Azure configuration missing")
+	}
+
+	return &DNSProvider{
+		clientId:       clientId,
+		clientSecret:   clientSecret,
+		subscriptionId: subscriptionId,
+		tenantId:       tenantId,
+		resourceGroup:  resourceGroup,
+	}, nil
+}
+
+// Timeout returns the timeout and interval to use when checking for DNS
+// propagation. Adjusting here to cope with spikes in propagation times.
+func (c *DNSProvider) Timeout() (timeout, interval time.Duration) {
+	return 120 * time.Second, 2 * time.Second
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+	zone, err := c.getHostedZoneID(fqdn)
+	if err != nil {
+		return err
+	}
+
+	rsc := dns.NewRecordSetsClient(c.subscriptionId)
+	rsc.Authorizer, err = c.newServicePrincipalTokenFromCredentials(azure.PublicCloud.ResourceManagerEndpoint)
+	relative := toRelativeRecord(fqdn, acme.ToFqdn(zone))
+	rec := dns.RecordSet{
+		Name: &relative,
+		RecordSetProperties: &dns.RecordSetProperties{
+			TTL:        to.Int64Ptr(60),
+			TXTRecords: &[]dns.TxtRecord{dns.TxtRecord{Value: &[]string{value}}},
+		},
+	}
+	_, err = rsc.CreateOrUpdate(c.resourceGroup, zone, relative, dns.TXT, rec, "", "")
+
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Returns the relative record to the domain
+func toRelativeRecord(domain, zone string) string {
+	return acme.UnFqdn(strings.TrimSuffix(domain, zone))
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	zone, err := c.getHostedZoneID(fqdn)
+	if err != nil {
+		return err
+	}
+
+	relative := toRelativeRecord(fqdn, acme.ToFqdn(zone))
+	rsc := dns.NewRecordSetsClient(c.subscriptionId)
+	rsc.Authorizer, err = c.newServicePrincipalTokenFromCredentials(azure.PublicCloud.ResourceManagerEndpoint)
+	_, err = rsc.Delete(c.resourceGroup, zone, relative, dns.TXT, "")
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Checks that azure has a zone for this domain name.
+func (c *DNSProvider) getHostedZoneID(fqdn string) (string, error) {
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return "", err
+	}
+
+	// Now we want to to Azure and get the zone.
+	dc := dns.NewZonesClient(c.subscriptionId)
+	dc.Authorizer, err = c.newServicePrincipalTokenFromCredentials(azure.PublicCloud.ResourceManagerEndpoint)
+	zone, err := dc.Get(c.resourceGroup, acme.UnFqdn(authZone))
+
+	if err != nil {
+		return "", err
+	}
+
+	// zone.Name shouldn't have a trailing dot(.)
+	return to.String(zone.Name), nil
+}
+
+// NewServicePrincipalTokenFromCredentials creates a new ServicePrincipalToken using values of the
+// passed credentials map.
+func (c *DNSProvider) newServicePrincipalTokenFromCredentials(scope string) (*azure.ServicePrincipalToken, error) {
+	oauthConfig, err := azure.PublicCloud.OAuthConfigForTenant(c.tenantId)
+	if err != nil {
+		panic(err)
+	}
+	return azure.NewServicePrincipalToken(*oauthConfig, c.clientId, c.clientSecret, scope)
+}

vendor/github.com/xenolf/lego/providers/dns/cloudflare/cloudflare.go

@@ -0,0 +1,223 @@
+// Package cloudflare implements a DNS provider for solving the DNS-01
+// challenge using cloudflare DNS.
+package cloudflare
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+)
+
+// CloudFlareAPIURL represents the API endpoint to call.
+// TODO: Unexport?
+const CloudFlareAPIURL = "https://api.cloudflare.com/client/v4"
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface
+type DNSProvider struct {
+	authEmail string
+	authKey   string
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for cloudflare.
+// Credentials must be passed in the environment variables: CLOUDFLARE_EMAIL
+// and CLOUDFLARE_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	email := os.Getenv("CLOUDFLARE_EMAIL")
+	key := os.Getenv("CLOUDFLARE_API_KEY")
+	return NewDNSProviderCredentials(email, key)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for cloudflare.
+func NewDNSProviderCredentials(email, key string) (*DNSProvider, error) {
+	if email == "" || key == "" {
+		return nil, fmt.Errorf("CloudFlare credentials missing")
+	}
+
+	return &DNSProvider{
+		authEmail: email,
+		authKey:   key,
+	}, nil
+}
+
+// Timeout returns the timeout and interval to use when checking for DNS
+// propagation. Adjusting here to cope with spikes in propagation times.
+func (c *DNSProvider) Timeout() (timeout, interval time.Duration) {
+	return 120 * time.Second, 2 * time.Second
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+	zoneID, err := c.getHostedZoneID(fqdn)
+	if err != nil {
+		return err
+	}
+
+	rec := cloudFlareRecord{
+		Type:    "TXT",
+		Name:    acme.UnFqdn(fqdn),
+		Content: value,
+		TTL:     120,
+	}
+
+	body, err := json.Marshal(rec)
+	if err != nil {
+		return err
+	}
+
+	_, err = c.makeRequest("POST", fmt.Sprintf("/zones/%s/dns_records", zoneID), bytes.NewReader(body))
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	record, err := c.findTxtRecord(fqdn)
+	if err != nil {
+		return err
+	}
+
+	_, err = c.makeRequest("DELETE", fmt.Sprintf("/zones/%s/dns_records/%s", record.ZoneID, record.ID), nil)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (c *DNSProvider) getHostedZoneID(fqdn string) (string, error) {
+	// HostedZone represents a CloudFlare DNS zone
+	type HostedZone struct {
+		ID   string `json:"id"`
+		Name string `json:"name"`
+	}
+
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return "", err
+	}
+
+	result, err := c.makeRequest("GET", "/zones?name="+acme.UnFqdn(authZone), nil)
+	if err != nil {
+		return "", err
+	}
+
+	var hostedZone []HostedZone
+	err = json.Unmarshal(result, &hostedZone)
+	if err != nil {
+		return "", err
+	}
+
+	if len(hostedZone) != 1 {
+		return "", fmt.Errorf("Zone %s not found in CloudFlare for domain %s", authZone, fqdn)
+	}
+
+	return hostedZone[0].ID, nil
+}
+
+func (c *DNSProvider) findTxtRecord(fqdn string) (*cloudFlareRecord, error) {
+	zoneID, err := c.getHostedZoneID(fqdn)
+	if err != nil {
+		return nil, err
+	}
+
+	result, err := c.makeRequest(
+		"GET",
+		fmt.Sprintf("/zones/%s/dns_records?per_page=1000&type=TXT&name=%s", zoneID, acme.UnFqdn(fqdn)),
+		nil,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	var records []cloudFlareRecord
+	err = json.Unmarshal(result, &records)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, rec := range records {
+		if rec.Name == acme.UnFqdn(fqdn) {
+			return &rec, nil
+		}
+	}
+
+	return nil, fmt.Errorf("No existing record found for %s", fqdn)
+}
+
+func (c *DNSProvider) makeRequest(method, uri string, body io.Reader) (json.RawMessage, error) {
+	// APIError contains error details for failed requests
+	type APIError struct {
+		Code       int        `json:"code,omitempty"`
+		Message    string     `json:"message,omitempty"`
+		ErrorChain []APIError `json:"error_chain,omitempty"`
+	}
+
+	// APIResponse represents a response from CloudFlare API
+	type APIResponse struct {
+		Success bool            `json:"success"`
+		Errors  []*APIError     `json:"errors"`
+		Result  json.RawMessage `json:"result"`
+	}
+
+	req, err := http.NewRequest(method, fmt.Sprintf("%s%s", CloudFlareAPIURL, uri), body)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Set("X-Auth-Email", c.authEmail)
+	req.Header.Set("X-Auth-Key", c.authKey)
+	//req.Header.Set("User-Agent", userAgent())
+
+	client := http.Client{Timeout: 30 * time.Second}
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("Error querying Cloudflare API -> %v", err)
+	}
+
+	defer resp.Body.Close()
+
+	var r APIResponse
+	err = json.NewDecoder(resp.Body).Decode(&r)
+	if err != nil {
+		return nil, err
+	}
+
+	if !r.Success {
+		if len(r.Errors) > 0 {
+			errStr := ""
+			for _, apiErr := range r.Errors {
+				errStr += fmt.Sprintf("\t Error: %d: %s", apiErr.Code, apiErr.Message)
+				for _, chainErr := range apiErr.ErrorChain {
+					errStr += fmt.Sprintf("<- %d: %s", chainErr.Code, chainErr.Message)
+				}
+			}
+			return nil, fmt.Errorf("Cloudflare API Error \n%s", errStr)
+		}
+		return nil, fmt.Errorf("Cloudflare API error")
+	}
+
+	return r.Result, nil
+}
+
+// cloudFlareRecord represents a CloudFlare DNS record
+type cloudFlareRecord struct {
+	Name    string `json:"name"`
+	Type    string `json:"type"`
+	Content string `json:"content"`
+	ID      string `json:"id,omitempty"`
+	TTL     int    `json:"ttl,omitempty"`
+	ZoneID  string `json:"zone_id,omitempty"`
+}

vendor/github.com/xenolf/lego/providers/dns/digitalocean/digitalocean.go

@@ -0,0 +1,166 @@
+// Package digitalocean implements a DNS provider for solving the DNS-01
+// challenge using digitalocean DNS.
+package digitalocean
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface
+// that uses DigitalOcean's REST API to manage TXT records for a domain.
+type DNSProvider struct {
+	apiAuthToken string
+	recordIDs    map[string]int
+	recordIDsMu  sync.Mutex
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for Digital
+// Ocean. Credentials must be passed in the environment variable:
+// DO_AUTH_TOKEN.
+func NewDNSProvider() (*DNSProvider, error) {
+	apiAuthToken := os.Getenv("DO_AUTH_TOKEN")
+	return NewDNSProviderCredentials(apiAuthToken)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for Digital Ocean.
+func NewDNSProviderCredentials(apiAuthToken string) (*DNSProvider, error) {
+	if apiAuthToken == "" {
+		return nil, fmt.Errorf("DigitalOcean credentials missing")
+	}
+	return &DNSProvider{
+		apiAuthToken: apiAuthToken,
+		recordIDs:    make(map[string]int),
+	}, nil
+}
+
+// Present creates a TXT record using the specified parameters
+func (d *DNSProvider) Present(domain, token, keyAuth string) error {
+	// txtRecordRequest represents the request body to DO's API to make a TXT record
+	type txtRecordRequest struct {
+		RecordType string `json:"type"`
+		Name       string `json:"name"`
+		Data       string `json:"data"`
+	}
+
+	// txtRecordResponse represents a response from DO's API after making a TXT record
+	type txtRecordResponse struct {
+		DomainRecord struct {
+			ID   int    `json:"id"`
+			Type string `json:"type"`
+			Name string `json:"name"`
+			Data string `json:"data"`
+		} `json:"domain_record"`
+	}
+
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return fmt.Errorf("Could not determine zone for domain: '%s'. %s", domain, err)
+	}
+
+	authZone = acme.UnFqdn(authZone)
+
+	reqURL := fmt.Sprintf("%s/v2/domains/%s/records", digitalOceanBaseURL, authZone)
+	reqData := txtRecordRequest{RecordType: "TXT", Name: fqdn, Data: value}
+	body, err := json.Marshal(reqData)
+	if err != nil {
+		return err
+	}
+
+	req, err := http.NewRequest("POST", reqURL, bytes.NewReader(body))
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", d.apiAuthToken))
+
+	client := http.Client{Timeout: 30 * time.Second}
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		var errInfo digitalOceanAPIError
+		json.NewDecoder(resp.Body).Decode(&errInfo)
+		return fmt.Errorf("HTTP %d: %s: %s", resp.StatusCode, errInfo.ID, errInfo.Message)
+	}
+
+	// Everything looks good; but we'll need the ID later to delete the record
+	var respData txtRecordResponse
+	err = json.NewDecoder(resp.Body).Decode(&respData)
+	if err != nil {
+		return err
+	}
+	d.recordIDsMu.Lock()
+	d.recordIDs[fqdn] = respData.DomainRecord.ID
+	d.recordIDsMu.Unlock()
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	// get the record's unique ID from when we created it
+	d.recordIDsMu.Lock()
+	recordID, ok := d.recordIDs[fqdn]
+	d.recordIDsMu.Unlock()
+	if !ok {
+		return fmt.Errorf("unknown record ID for '%s'", fqdn)
+	}
+
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return fmt.Errorf("Could not determine zone for domain: '%s'. %s", domain, err)
+	}
+
+	authZone = acme.UnFqdn(authZone)
+
+	reqURL := fmt.Sprintf("%s/v2/domains/%s/records/%d", digitalOceanBaseURL, authZone, recordID)
+	req, err := http.NewRequest("DELETE", reqURL, nil)
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", d.apiAuthToken))
+
+	client := http.Client{Timeout: 30 * time.Second}
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		var errInfo digitalOceanAPIError
+		json.NewDecoder(resp.Body).Decode(&errInfo)
+		return fmt.Errorf("HTTP %d: %s: %s", resp.StatusCode, errInfo.ID, errInfo.Message)
+	}
+
+	// Delete record ID from map
+	d.recordIDsMu.Lock()
+	delete(d.recordIDs, fqdn)
+	d.recordIDsMu.Unlock()
+
+	return nil
+}
+
+type digitalOceanAPIError struct {
+	ID      string `json:"id"`
+	Message string `json:"message"`
+}
+
+var digitalOceanBaseURL = "https://api.digitalocean.com"

vendor/github.com/xenolf/lego/providers/dns/dns_providers.go

@@ -0,0 +1,80 @@
+// Factory for DNS providers
+package dns
+
+import (
+	"fmt"
+
+	"github.com/xenolf/lego/acme"
+	"github.com/xenolf/lego/providers/dns/auroradns"
+	"github.com/xenolf/lego/providers/dns/azure"
+	"github.com/xenolf/lego/providers/dns/cloudflare"
+	"github.com/xenolf/lego/providers/dns/digitalocean"
+	"github.com/xenolf/lego/providers/dns/dnsimple"
+	"github.com/xenolf/lego/providers/dns/dnsmadeeasy"
+	"github.com/xenolf/lego/providers/dns/dnspod"
+	"github.com/xenolf/lego/providers/dns/dyn"
+	"github.com/xenolf/lego/providers/dns/exoscale"
+	"github.com/xenolf/lego/providers/dns/gandi"
+	"github.com/xenolf/lego/providers/dns/googlecloud"
+	"github.com/xenolf/lego/providers/dns/linode"
+	"github.com/xenolf/lego/providers/dns/namecheap"
+	"github.com/xenolf/lego/providers/dns/ns1"
+	"github.com/xenolf/lego/providers/dns/ovh"
+	"github.com/xenolf/lego/providers/dns/pdns"
+	"github.com/xenolf/lego/providers/dns/rackspace"
+	"github.com/xenolf/lego/providers/dns/rfc2136"
+	"github.com/xenolf/lego/providers/dns/route53"
+	"github.com/xenolf/lego/providers/dns/vultr"
+)
+
+func NewDNSChallengeProviderByName(name string) (acme.ChallengeProvider, error) {
+	var err error
+	var provider acme.ChallengeProvider
+	switch name {
+	case "azure":
+		provider, err = azure.NewDNSProvider()
+	case "auroradns":
+		provider, err = auroradns.NewDNSProvider()
+	case "cloudflare":
+		provider, err = cloudflare.NewDNSProvider()
+	case "digitalocean":
+		provider, err = digitalocean.NewDNSProvider()
+	case "dnsimple":
+		provider, err = dnsimple.NewDNSProvider()
+	case "dnsmadeeasy":
+		provider, err = dnsmadeeasy.NewDNSProvider()
+	case "dnspod":
+		provider, err = dnspod.NewDNSProvider()
+	case "dyn":
+		provider, err = dyn.NewDNSProvider()
+	case "exoscale":
+		provider, err = exoscale.NewDNSProvider()		
+	case "gandi":
+		provider, err = gandi.NewDNSProvider()
+	case "gcloud":
+		provider, err = googlecloud.NewDNSProvider()
+	case "linode":
+		provider, err = linode.NewDNSProvider()
+	case "manual":
+		provider, err = acme.NewDNSProviderManual()
+	case "namecheap":
+		provider, err = namecheap.NewDNSProvider()
+	case "rackspace":
+		provider, err = rackspace.NewDNSProvider()
+	case "route53":
+		provider, err = route53.NewDNSProvider()
+	case "rfc2136":
+		provider, err = rfc2136.NewDNSProvider()
+	case "vultr":
+		provider, err = vultr.NewDNSProvider()
+	case "ovh":
+		provider, err = ovh.NewDNSProvider()
+	case "pdns":
+		provider, err = pdns.NewDNSProvider()
+	case "ns1":
+		provider, err = ns1.NewDNSProvider()
+	default:
+		err = fmt.Errorf("Unrecognised DNS provider: %s", name)
+	}
+	return provider, err
+}

vendor/github.com/xenolf/lego/providers/dns/dnsimple/dnsimple.go

@@ -0,0 +1,141 @@
+// Package dnsimple implements a DNS provider for solving the DNS-01 challenge
+// using dnsimple DNS.
+package dnsimple
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/weppos/dnsimple-go/dnsimple"
+	"github.com/xenolf/lego/acme"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface.
+type DNSProvider struct {
+	client *dnsimple.Client
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for dnsimple.
+// Credentials must be passed in the environment variables: DNSIMPLE_EMAIL
+// and DNSIMPLE_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	email := os.Getenv("DNSIMPLE_EMAIL")
+	key := os.Getenv("DNSIMPLE_API_KEY")
+	return NewDNSProviderCredentials(email, key)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for dnsimple.
+func NewDNSProviderCredentials(email, key string) (*DNSProvider, error) {
+	if email == "" || key == "" {
+		return nil, fmt.Errorf("DNSimple credentials missing")
+	}
+
+	return &DNSProvider{
+		client: dnsimple.NewClient(key, email),
+	}, nil
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge.
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+
+	zoneID, zoneName, err := c.getHostedZone(domain)
+	if err != nil {
+		return err
+	}
+
+	recordAttributes := c.newTxtRecord(zoneName, fqdn, value, ttl)
+	_, _, err = c.client.Domains.CreateRecord(zoneID, *recordAttributes)
+	if err != nil {
+		return fmt.Errorf("DNSimple API call failed: %v", err)
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters.
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	records, err := c.findTxtRecords(domain, fqdn)
+	if err != nil {
+		return err
+	}
+
+	for _, rec := range records {
+		_, err := c.client.Domains.DeleteRecord(rec.DomainId, rec.Id)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (c *DNSProvider) getHostedZone(domain string) (string, string, error) {
+	zones, _, err := c.client.Domains.List()
+	if err != nil {
+		return "", "", fmt.Errorf("DNSimple API call failed: %v", err)
+	}
+
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return "", "", err
+	}
+
+	var hostedZone dnsimple.Domain
+	for _, zone := range zones {
+		if zone.Name == acme.UnFqdn(authZone) {
+			hostedZone = zone
+		}
+	}
+
+	if hostedZone.Id == 0 {
+		return "", "", fmt.Errorf("Zone %s not found in DNSimple for domain %s", authZone, domain)
+
+	}
+
+	return fmt.Sprintf("%v", hostedZone.Id), hostedZone.Name, nil
+}
+
+func (c *DNSProvider) findTxtRecords(domain, fqdn string) ([]dnsimple.Record, error) {
+	zoneID, zoneName, err := c.getHostedZone(domain)
+	if err != nil {
+		return nil, err
+	}
+
+	var records []dnsimple.Record
+	result, _, err := c.client.Domains.ListRecords(zoneID, "", "TXT")
+	if err != nil {
+		return records, fmt.Errorf("DNSimple API call has failed: %v", err)
+	}
+
+	recordName := c.extractRecordName(fqdn, zoneName)
+	for _, record := range result {
+		if record.Name == recordName {
+			records = append(records, record)
+		}
+	}
+
+	return records, nil
+}
+
+func (c *DNSProvider) newTxtRecord(zone, fqdn, value string, ttl int) *dnsimple.Record {
+	name := c.extractRecordName(fqdn, zone)
+
+	return &dnsimple.Record{
+		Type:    "TXT",
+		Name:    name,
+		Content: value,
+		TTL:     ttl,
+	}
+}
+
+func (c *DNSProvider) extractRecordName(fqdn, domain string) string {
+	name := acme.UnFqdn(fqdn)
+	if idx := strings.Index(name, "."+domain); idx != -1 {
+		return name[:idx]
+	}
+	return name
+}

vendor/github.com/xenolf/lego/providers/dns/dnsmadeeasy/dnsmadeeasy.go

@@ -0,0 +1,248 @@
+package dnsmadeeasy
+
+import (
+	"bytes"
+	"crypto/hmac"
+	"crypto/sha1"
+	"crypto/tls"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface that uses
+// DNSMadeEasy's DNS API to manage TXT records for a domain.
+type DNSProvider struct {
+	baseURL   string
+	apiKey    string
+	apiSecret string
+}
+
+// Domain holds the DNSMadeEasy API representation of a Domain
+type Domain struct {
+	ID   int    `json:"id"`
+	Name string `json:"name"`
+}
+
+// Record holds the DNSMadeEasy API representation of a Domain Record
+type Record struct {
+	ID       int    `json:"id"`
+	Type     string `json:"type"`
+	Name     string `json:"name"`
+	Value    string `json:"value"`
+	TTL      int    `json:"ttl"`
+	SourceID int    `json:"sourceId"`
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for DNSMadeEasy DNS.
+// Credentials must be passed in the environment variables: DNSMADEEASY_API_KEY
+// and DNSMADEEASY_API_SECRET.
+func NewDNSProvider() (*DNSProvider, error) {
+	dnsmadeeasyAPIKey := os.Getenv("DNSMADEEASY_API_KEY")
+	dnsmadeeasyAPISecret := os.Getenv("DNSMADEEASY_API_SECRET")
+	dnsmadeeasySandbox := os.Getenv("DNSMADEEASY_SANDBOX")
+
+	var baseURL string
+
+	sandbox, _ := strconv.ParseBool(dnsmadeeasySandbox)
+	if sandbox {
+		baseURL = "https://api.sandbox.dnsmadeeasy.com/V2.0"
+	} else {
+		baseURL = "https://api.dnsmadeeasy.com/V2.0"
+	}
+
+	return NewDNSProviderCredentials(baseURL, dnsmadeeasyAPIKey, dnsmadeeasyAPISecret)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for DNSMadeEasy.
+func NewDNSProviderCredentials(baseURL, apiKey, apiSecret string) (*DNSProvider, error) {
+	if baseURL == "" || apiKey == "" || apiSecret == "" {
+		return nil, fmt.Errorf("DNS Made Easy credentials missing")
+	}
+
+	return &DNSProvider{
+		baseURL:   baseURL,
+		apiKey:    apiKey,
+		apiSecret: apiSecret,
+	}, nil
+}
+
+// Present creates a TXT record using the specified parameters
+func (d *DNSProvider) Present(domainName, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domainName, keyAuth)
+
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return err
+	}
+
+	// fetch the domain details
+	domain, err := d.getDomain(authZone)
+	if err != nil {
+		return err
+	}
+
+	// create the TXT record
+	name := strings.Replace(fqdn, "."+authZone, "", 1)
+	record := &Record{Type: "TXT", Name: name, Value: value, TTL: ttl}
+
+	err = d.createRecord(domain, record)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT records matching the specified parameters
+func (d *DNSProvider) CleanUp(domainName, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domainName, keyAuth)
+
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return err
+	}
+
+	// fetch the domain details
+	domain, err := d.getDomain(authZone)
+	if err != nil {
+		return err
+	}
+
+	// find matching records
+	name := strings.Replace(fqdn, "."+authZone, "", 1)
+	records, err := d.getRecords(domain, name, "TXT")
+	if err != nil {
+		return err
+	}
+
+	// delete records
+	for _, record := range *records {
+		err = d.deleteRecord(record)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (d *DNSProvider) getDomain(authZone string) (*Domain, error) {
+	domainName := authZone[0 : len(authZone)-1]
+	resource := fmt.Sprintf("%s%s", "/dns/managed/name?domainname=", domainName)
+
+	resp, err := d.sendRequest("GET", resource, nil)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	domain := &Domain{}
+	err = json.NewDecoder(resp.Body).Decode(&domain)
+	if err != nil {
+		return nil, err
+	}
+
+	return domain, nil
+}
+
+func (d *DNSProvider) getRecords(domain *Domain, recordName, recordType string) (*[]Record, error) {
+	resource := fmt.Sprintf("%s/%d/%s%s%s%s", "/dns/managed", domain.ID, "records?recordName=", recordName, "&type=", recordType)
+
+	resp, err := d.sendRequest("GET", resource, nil)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	type recordsResponse struct {
+		Records *[]Record `json:"data"`
+	}
+
+	records := &recordsResponse{}
+	err = json.NewDecoder(resp.Body).Decode(&records)
+	if err != nil {
+		return nil, err
+	}
+
+	return records.Records, nil
+}
+
+func (d *DNSProvider) createRecord(domain *Domain, record *Record) error {
+	url := fmt.Sprintf("%s/%d/%s", "/dns/managed", domain.ID, "records")
+
+	resp, err := d.sendRequest("POST", url, record)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	return nil
+}
+
+func (d *DNSProvider) deleteRecord(record Record) error {
+	resource := fmt.Sprintf("%s/%d/%s/%d", "/dns/managed", record.SourceID, "records", record.ID)
+
+	resp, err := d.sendRequest("DELETE", resource, nil)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	return nil
+}
+
+func (d *DNSProvider) sendRequest(method, resource string, payload interface{}) (*http.Response, error) {
+	url := fmt.Sprintf("%s%s", d.baseURL, resource)
+
+	body, err := json.Marshal(payload)
+	if err != nil {
+		return nil, err
+	}
+
+	timestamp := time.Now().UTC().Format(time.RFC1123)
+	signature := computeHMAC(timestamp, d.apiSecret)
+
+	req, err := http.NewRequest(method, url, bytes.NewReader(body))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("x-dnsme-apiKey", d.apiKey)
+	req.Header.Set("x-dnsme-requestDate", timestamp)
+	req.Header.Set("x-dnsme-hmac", signature)
+	req.Header.Set("accept", "application/json")
+	req.Header.Set("content-type", "application/json")
+
+	transport := &http.Transport{
+		TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
+	}
+	client := &http.Client{
+		Transport: transport,
+		Timeout:   time.Duration(10 * time.Second),
+	}
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode > 299 {
+		return nil, fmt.Errorf("DNSMadeEasy API request failed with HTTP status code %d", resp.StatusCode)
+	}
+
+	return resp, nil
+}
+
+func computeHMAC(message string, secret string) string {
+	key := []byte(secret)
+	h := hmac.New(sha1.New, key)
+	h.Write([]byte(message))
+	return hex.EncodeToString(h.Sum(nil))
+}

vendor/github.com/xenolf/lego/providers/dns/dnspod/dnspod.go

@@ -0,0 +1,146 @@
+// Package dnspod implements a DNS provider for solving the DNS-01 challenge
+// using dnspod DNS.
+package dnspod
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/decker502/dnspod-go"
+	"github.com/xenolf/lego/acme"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface.
+type DNSProvider struct {
+	client *dnspod.Client
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for dnspod.
+// Credentials must be passed in the environment variables: DNSPOD_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	key := os.Getenv("DNSPOD_API_KEY")
+	return NewDNSProviderCredentials(key)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for dnspod.
+func NewDNSProviderCredentials(key string) (*DNSProvider, error) {
+	if key == "" {
+		return nil, fmt.Errorf("dnspod credentials missing")
+	}
+
+	params := dnspod.CommonParams{LoginToken: key, Format: "json"}
+	return &DNSProvider{
+		client: dnspod.NewClient(params),
+	}, nil
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge.
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+	zoneID, zoneName, err := c.getHostedZone(domain)
+	if err != nil {
+		return err
+	}
+
+	recordAttributes := c.newTxtRecord(zoneName, fqdn, value, ttl)
+	_, _, err = c.client.Domains.CreateRecord(zoneID, *recordAttributes)
+	if err != nil {
+		return fmt.Errorf("dnspod API call failed: %v", err)
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters.
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	records, err := c.findTxtRecords(domain, fqdn)
+	if err != nil {
+		return err
+	}
+
+	zoneID, _, err := c.getHostedZone(domain)
+	if err != nil {
+		return err
+	}
+
+	for _, rec := range records {
+		_, err := c.client.Domains.DeleteRecord(zoneID, rec.ID)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (c *DNSProvider) getHostedZone(domain string) (string, string, error) {
+	zones, _, err := c.client.Domains.List()
+	if err != nil {
+		return "", "", fmt.Errorf("dnspod API call failed: %v", err)
+	}
+
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return "", "", err
+	}
+
+	var hostedZone dnspod.Domain
+	for _, zone := range zones {
+		if zone.Name == acme.UnFqdn(authZone) {
+			hostedZone = zone
+		}
+	}
+
+	if hostedZone.ID == 0 {
+		return "", "", fmt.Errorf("Zone %s not found in dnspod for domain %s", authZone, domain)
+
+	}
+
+	return fmt.Sprintf("%v", hostedZone.ID), hostedZone.Name, nil
+}
+
+func (c *DNSProvider) newTxtRecord(zone, fqdn, value string, ttl int) *dnspod.Record {
+	name := c.extractRecordName(fqdn, zone)
+
+	return &dnspod.Record{
+		Type:  "TXT",
+		Name:  name,
+		Value: value,
+		Line:  "默认",
+		TTL:   "600",
+	}
+}
+
+func (c *DNSProvider) findTxtRecords(domain, fqdn string) ([]dnspod.Record, error) {
+	zoneID, zoneName, err := c.getHostedZone(domain)
+	if err != nil {
+		return nil, err
+	}
+
+	var records []dnspod.Record
+	result, _, err := c.client.Domains.ListRecords(zoneID, "")
+	if err != nil {
+		return records, fmt.Errorf("dnspod API call has failed: %v", err)
+	}
+
+	recordName := c.extractRecordName(fqdn, zoneName)
+
+	for _, record := range result {
+		if record.Name == recordName {
+			records = append(records, record)
+		}
+	}
+
+	return records, nil
+}
+
+func (c *DNSProvider) extractRecordName(fqdn, domain string) string {
+	name := acme.UnFqdn(fqdn)
+	if idx := strings.Index(name, "."+domain); idx != -1 {
+		return name[:idx]
+	}
+	return name
+}

vendor/github.com/xenolf/lego/providers/dns/dyn/dyn.go

@@ -0,0 +1,274 @@
+// Package dyn implements a DNS provider for solving the DNS-01 challenge
+// using Dyn Managed DNS.
+package dyn
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"strconv"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+)
+
+var dynBaseURL = "https://api.dynect.net/REST"
+
+type dynResponse struct {
+	// One of 'success', 'failure', or 'incomplete'
+	Status string `json:"status"`
+
+	// The structure containing the actual results of the request
+	Data json.RawMessage `json:"data"`
+
+	// The ID of the job that was created in response to a request.
+	JobID int `json:"job_id"`
+
+	// A list of zero or more messages
+	Messages json.RawMessage `json:"msgs"`
+}
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface that uses
+// Dyn's Managed DNS API to manage TXT records for a domain.
+type DNSProvider struct {
+	customerName string
+	userName     string
+	password     string
+	token        string
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for Dyn DNS.
+// Credentials must be passed in the environment variables: DYN_CUSTOMER_NAME,
+// DYN_USER_NAME and DYN_PASSWORD.
+func NewDNSProvider() (*DNSProvider, error) {
+	customerName := os.Getenv("DYN_CUSTOMER_NAME")
+	userName := os.Getenv("DYN_USER_NAME")
+	password := os.Getenv("DYN_PASSWORD")
+	return NewDNSProviderCredentials(customerName, userName, password)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for Dyn DNS.
+func NewDNSProviderCredentials(customerName, userName, password string) (*DNSProvider, error) {
+	if customerName == "" || userName == "" || password == "" {
+		return nil, fmt.Errorf("DynDNS credentials missing")
+	}
+
+	return &DNSProvider{
+		customerName: customerName,
+		userName:     userName,
+		password:     password,
+	}, nil
+}
+
+func (d *DNSProvider) sendRequest(method, resource string, payload interface{}) (*dynResponse, error) {
+	url := fmt.Sprintf("%s/%s", dynBaseURL, resource)
+
+	body, err := json.Marshal(payload)
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequest(method, url, bytes.NewReader(body))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	if len(d.token) > 0 {
+		req.Header.Set("Auth-Token", d.token)
+	}
+
+	client := &http.Client{Timeout: time.Duration(10 * time.Second)}
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		return nil, fmt.Errorf("Dyn API request failed with HTTP status code %d", resp.StatusCode)
+	} else if resp.StatusCode == 307 {
+		// TODO add support for HTTP 307 response and long running jobs
+		return nil, fmt.Errorf("Dyn API request returned HTTP 307. This is currently unsupported")
+	}
+
+	var dynRes dynResponse
+	err = json.NewDecoder(resp.Body).Decode(&dynRes)
+	if err != nil {
+		return nil, err
+	}
+
+	if dynRes.Status == "failure" {
+		// TODO add better error handling
+		return nil, fmt.Errorf("Dyn API request failed: %s", dynRes.Messages)
+	}
+
+	return &dynRes, nil
+}
+
+// Starts a new Dyn API Session. Authenticates using customerName, userName,
+// password and receives a token to be used in for subsequent requests.
+func (d *DNSProvider) login() error {
+	type creds struct {
+		Customer string `json:"customer_name"`
+		User     string `json:"user_name"`
+		Pass     string `json:"password"`
+	}
+
+	type session struct {
+		Token   string `json:"token"`
+		Version string `json:"version"`
+	}
+
+	payload := &creds{Customer: d.customerName, User: d.userName, Pass: d.password}
+	dynRes, err := d.sendRequest("POST", "Session", payload)
+	if err != nil {
+		return err
+	}
+
+	var s session
+	err = json.Unmarshal(dynRes.Data, &s)
+	if err != nil {
+		return err
+	}
+
+	d.token = s.Token
+
+	return nil
+}
+
+// Destroys Dyn Session
+func (d *DNSProvider) logout() error {
+	if len(d.token) == 0 {
+		// nothing to do
+		return nil
+	}
+
+	url := fmt.Sprintf("%s/Session", dynBaseURL)
+	req, err := http.NewRequest("DELETE", url, nil)
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Auth-Token", d.token)
+
+	client := &http.Client{Timeout: time.Duration(10 * time.Second)}
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return fmt.Errorf("Dyn API request failed to delete session with HTTP status code %d", resp.StatusCode)
+	}
+
+	d.token = ""
+
+	return nil
+}
+
+// Present creates a TXT record using the specified parameters
+func (d *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return err
+	}
+
+	err = d.login()
+	if err != nil {
+		return err
+	}
+
+	data := map[string]interface{}{
+		"rdata": map[string]string{
+			"txtdata": value,
+		},
+		"ttl": strconv.Itoa(ttl),
+	}
+
+	resource := fmt.Sprintf("TXTRecord/%s/%s/", authZone, fqdn)
+	_, err = d.sendRequest("POST", resource, data)
+	if err != nil {
+		return err
+	}
+
+	err = d.publish(authZone, "Added TXT record for ACME dns-01 challenge using lego client")
+	if err != nil {
+		return err
+	}
+
+	err = d.logout()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (d *DNSProvider) publish(zone, notes string) error {
+	type publish struct {
+		Publish bool   `json:"publish"`
+		Notes   string `json:"notes"`
+	}
+
+	pub := &publish{Publish: true, Notes: notes}
+	resource := fmt.Sprintf("Zone/%s/", zone)
+	_, err := d.sendRequest("PUT", resource, pub)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return err
+	}
+
+	err = d.login()
+	if err != nil {
+		return err
+	}
+
+	resource := fmt.Sprintf("TXTRecord/%s/%s/", authZone, fqdn)
+	url := fmt.Sprintf("%s/%s", dynBaseURL, resource)
+	req, err := http.NewRequest("DELETE", url, nil)
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Auth-Token", d.token)
+
+	client := &http.Client{Timeout: time.Duration(10 * time.Second)}
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+	resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return fmt.Errorf("Dyn API request failed to delete TXT record HTTP status code %d", resp.StatusCode)
+	}
+
+	err = d.publish(authZone, "Removed TXT record for ACME dns-01 challenge using lego client")
+	if err != nil {
+		return err
+	}
+
+	err = d.logout()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

vendor/github.com/xenolf/lego/providers/dns/exoscale/exoscale.go

@@ -0,0 +1,132 @@
+// Package exoscale implements a DNS provider for solving the DNS-01 challenge
+// using exoscale DNS.
+package exoscale
+
+import (
+	"errors"
+	"fmt"
+	"os"
+
+	"github.com/pyr/egoscale/src/egoscale"
+	"github.com/xenolf/lego/acme"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface.
+type DNSProvider struct {
+	client *egoscale.Client
+}
+
+// Credentials must be passed in the environment variables:
+// EXOSCALE_API_KEY, EXOSCALE_API_SECRET, EXOSCALE_ENDPOINT.
+func NewDNSProvider() (*DNSProvider, error) {
+	key := os.Getenv("EXOSCALE_API_KEY")
+	secret := os.Getenv("EXOSCALE_API_SECRET")
+	endpoint := os.Getenv("EXOSCALE_ENDPOINT")
+	return NewDNSProviderClient(key, secret, endpoint)
+}
+
+// Uses the supplied parameters to return a DNSProvider instance
+// configured for Exoscale.
+func NewDNSProviderClient(key, secret, endpoint string) (*DNSProvider, error) {
+	if key == "" || secret == "" {
+		return nil, fmt.Errorf("Exoscale credentials missing")
+	}
+	if endpoint == "" {
+		endpoint = "https://api.exoscale.ch/dns"
+	}
+
+	return &DNSProvider{
+		client: egoscale.NewClient(endpoint, key, secret),
+	}, nil
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge.
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+	zone, recordName, err := c.FindZoneAndRecordName(fqdn, domain)
+	if err != nil {
+		return err
+	}
+
+	recordId, err := c.FindExistingRecordId(zone, recordName)
+	if err != nil {
+		return err
+	}
+
+	record := egoscale.DNSRecord{
+		Name:       recordName,
+		Ttl:        ttl,
+		Content:    value,
+		RecordType: "TXT",
+	}
+
+	if recordId == 0 {
+		_, err := c.client.CreateRecord(zone, record)
+		if err != nil {
+			return errors.New("Error while creating DNS record: " + err.Error())
+		}
+	} else {
+		record.Id = recordId
+		_, err := c.client.UpdateRecord(zone, record)
+		if err != nil {
+			return errors.New("Error while updating DNS record: " + err.Error())
+		}
+	}
+
+	return nil
+}
+
+// CleanUp removes the record matching the specified parameters.
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+	zone, recordName, err := c.FindZoneAndRecordName(fqdn, domain)
+	if err != nil {
+		return err
+	}
+
+	recordId, err := c.FindExistingRecordId(zone, recordName)
+	if err != nil {
+		return err
+	}
+
+	if recordId != 0 {
+		record := egoscale.DNSRecord{
+			Id: recordId,
+		}
+
+		err = c.client.DeleteRecord(zone, record)
+		if err != nil {
+			return errors.New("Error while deleting DNS record: " + err.Error())
+		}
+	}
+
+	return nil
+}
+
+// Query Exoscale to find an existing record for this name.
+// Returns nil if no record could be found
+func (c *DNSProvider) FindExistingRecordId(zone, recordName string) (int64, error) {
+	responses, err := c.client.GetRecords(zone)
+	if err != nil {
+		return -1, errors.New("Error while retrievening DNS records: " + err.Error())
+	}
+	for _, response := range responses {
+		if response.Record.Name == recordName {
+			return response.Record.Id, nil
+		}
+	}
+	return 0, nil
+}
+
+// Extract DNS zone and DNS entry name
+func (c *DNSProvider) FindZoneAndRecordName(fqdn, domain string) (string, string, error) {
+	zone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return "", "", err
+	}
+	zone = acme.UnFqdn(zone)
+	name := acme.UnFqdn(fqdn)
+	name = name[:len(name)-len("."+zone)]
+
+	return zone, name, nil
+}

vendor/github.com/xenolf/lego/providers/dns/gandi/gandi.go

@@ -0,0 +1,472 @@
+// Package gandi implements a DNS provider for solving the DNS-01
+// challenge using Gandi DNS.
+package gandi
+
+import (
+	"bytes"
+	"encoding/xml"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+)
+
+// Gandi API reference:       http://doc.rpc.gandi.net/index.html
+// Gandi API domain examples: http://doc.rpc.gandi.net/domain/faq.html
+
+var (
+	// endpoint is the Gandi XML-RPC endpoint used by Present and
+	// CleanUp. It is overridden during tests.
+	endpoint = "https://rpc.gandi.net/xmlrpc/"
+	// findZoneByFqdn determines the DNS zone of an fqdn. It is overridden
+	// during tests.
+	findZoneByFqdn = acme.FindZoneByFqdn
+)
+
+// inProgressInfo contains information about an in-progress challenge
+type inProgressInfo struct {
+	zoneID    int    // zoneID of gandi zone to restore in CleanUp
+	newZoneID int    // zoneID of temporary gandi zone containing TXT record
+	authZone  string // the domain name registered at gandi with trailing "."
+}
+
+// DNSProvider is an implementation of the
+// acme.ChallengeProviderTimeout interface that uses Gandi's XML-RPC
+// API to manage TXT records for a domain.
+type DNSProvider struct {
+	apiKey              string
+	inProgressFQDNs     map[string]inProgressInfo
+	inProgressAuthZones map[string]struct{}
+	inProgressMu        sync.Mutex
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for Gandi.
+// Credentials must be passed in the environment variable: GANDI_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	apiKey := os.Getenv("GANDI_API_KEY")
+	return NewDNSProviderCredentials(apiKey)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for Gandi.
+func NewDNSProviderCredentials(apiKey string) (*DNSProvider, error) {
+	if apiKey == "" {
+		return nil, fmt.Errorf("No Gandi API Key given")
+	}
+	return &DNSProvider{
+		apiKey:              apiKey,
+		inProgressFQDNs:     make(map[string]inProgressInfo),
+		inProgressAuthZones: make(map[string]struct{}),
+	}, nil
+}
+
+// Present creates a TXT record using the specified parameters. It
+// does this by creating and activating a new temporary Gandi DNS
+// zone. This new zone contains the TXT record.
+func (d *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+	if ttl < 300 {
+		ttl = 300 // 300 is gandi minimum value for ttl
+	}
+	// find authZone and Gandi zone_id for fqdn
+	authZone, err := findZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return fmt.Errorf("Gandi DNS: findZoneByFqdn failure: %v", err)
+	}
+	zoneID, err := d.getZoneID(authZone)
+	if err != nil {
+		return err
+	}
+	// determine name of TXT record
+	if !strings.HasSuffix(
+		strings.ToLower(fqdn), strings.ToLower("."+authZone)) {
+		return fmt.Errorf(
+			"Gandi DNS: unexpected authZone %s for fqdn %s", authZone, fqdn)
+	}
+	name := fqdn[:len(fqdn)-len("."+authZone)]
+	// acquire lock and check there is not a challenge already in
+	// progress for this value of authZone
+	d.inProgressMu.Lock()
+	defer d.inProgressMu.Unlock()
+	if _, ok := d.inProgressAuthZones[authZone]; ok {
+		return fmt.Errorf(
+			"Gandi DNS: challenge already in progress for authZone %s",
+			authZone)
+	}
+	// perform API actions to create and activate new gandi zone
+	// containing the required TXT record
+	newZoneName := fmt.Sprintf(
+		"%s [ACME Challenge %s]",
+		acme.UnFqdn(authZone), time.Now().Format(time.RFC822Z))
+	newZoneID, err := d.cloneZone(zoneID, newZoneName)
+	if err != nil {
+		return err
+	}
+	newZoneVersion, err := d.newZoneVersion(newZoneID)
+	if err != nil {
+		return err
+	}
+	err = d.addTXTRecord(newZoneID, newZoneVersion, name, value, ttl)
+	if err != nil {
+		return err
+	}
+	err = d.setZoneVersion(newZoneID, newZoneVersion)
+	if err != nil {
+		return err
+	}
+	err = d.setZone(authZone, newZoneID)
+	if err != nil {
+		return err
+	}
+	// save data necessary for CleanUp
+	d.inProgressFQDNs[fqdn] = inProgressInfo{
+		zoneID:    zoneID,
+		newZoneID: newZoneID,
+		authZone:  authZone,
+	}
+	d.inProgressAuthZones[authZone] = struct{}{}
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified
+// parameters. It does this by restoring the old Gandi DNS zone and
+// removing the temporary one created by Present.
+func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+	// acquire lock and retrieve zoneID, newZoneID and authZone
+	d.inProgressMu.Lock()
+	defer d.inProgressMu.Unlock()
+	if _, ok := d.inProgressFQDNs[fqdn]; !ok {
+		// if there is no cleanup information then just return
+		return nil
+	}
+	zoneID := d.inProgressFQDNs[fqdn].zoneID
+	newZoneID := d.inProgressFQDNs[fqdn].newZoneID
+	authZone := d.inProgressFQDNs[fqdn].authZone
+	delete(d.inProgressFQDNs, fqdn)
+	delete(d.inProgressAuthZones, authZone)
+	// perform API actions to restore old gandi zone for authZone
+	err := d.setZone(authZone, zoneID)
+	if err != nil {
+		return err
+	}
+	err = d.deleteZone(newZoneID)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// Timeout returns the values (40*time.Minute, 60*time.Second) which
+// are used by the acme package as timeout and check interval values
+// when checking for DNS record propagation with Gandi.
+func (d *DNSProvider) Timeout() (timeout, interval time.Duration) {
+	return 40 * time.Minute, 60 * time.Second
+}
+
+// types for XML-RPC method calls and parameters
+
+type param interface {
+	param()
+}
+type paramString struct {
+	XMLName xml.Name `xml:"param"`
+	Value   string   `xml:"value>string"`
+}
+type paramInt struct {
+	XMLName xml.Name `xml:"param"`
+	Value   int      `xml:"value>int"`
+}
+
+type structMember interface {
+	structMember()
+}
+type structMemberString struct {
+	Name  string `xml:"name"`
+	Value string `xml:"value>string"`
+}
+type structMemberInt struct {
+	Name  string `xml:"name"`
+	Value int    `xml:"value>int"`
+}
+type paramStruct struct {
+	XMLName       xml.Name       `xml:"param"`
+	StructMembers []structMember `xml:"value>struct>member"`
+}
+
+func (p paramString) param()               {}
+func (p paramInt) param()                  {}
+func (m structMemberString) structMember() {}
+func (m structMemberInt) structMember()    {}
+func (p paramStruct) param()               {}
+
+type methodCall struct {
+	XMLName    xml.Name `xml:"methodCall"`
+	MethodName string   `xml:"methodName"`
+	Params     []param  `xml:"params"`
+}
+
+// types for XML-RPC responses
+
+type response interface {
+	faultCode() int
+	faultString() string
+}
+
+type responseFault struct {
+	FaultCode   int    `xml:"fault>value>struct>member>value>int"`
+	FaultString string `xml:"fault>value>struct>member>value>string"`
+}
+
+func (r responseFault) faultCode() int      { return r.FaultCode }
+func (r responseFault) faultString() string { return r.FaultString }
+
+type responseStruct struct {
+	responseFault
+	StructMembers []struct {
+		Name     string `xml:"name"`
+		ValueInt int    `xml:"value>int"`
+	} `xml:"params>param>value>struct>member"`
+}
+
+type responseInt struct {
+	responseFault
+	Value int `xml:"params>param>value>int"`
+}
+
+type responseBool struct {
+	responseFault
+	Value bool `xml:"params>param>value>boolean"`
+}
+
+// POSTing/Marshalling/Unmarshalling
+
+type rpcError struct {
+	faultCode   int
+	faultString string
+}
+
+func (e rpcError) Error() string {
+	return fmt.Sprintf(
+		"Gandi DNS: RPC Error: (%d) %s", e.faultCode, e.faultString)
+}
+
+func httpPost(url string, bodyType string, body io.Reader) ([]byte, error) {
+	client := http.Client{Timeout: 60 * time.Second}
+	resp, err := client.Post(url, bodyType, body)
+	if err != nil {
+		return nil, fmt.Errorf("Gandi DNS: HTTP Post Error: %v", err)
+	}
+	defer resp.Body.Close()
+	b, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("Gandi DNS: HTTP Post Error: %v", err)
+	}
+	return b, nil
+}
+
+// rpcCall makes an XML-RPC call to Gandi's RPC endpoint by
+// marshalling the data given in the call argument to XML and sending
+// that via HTTP Post to Gandi. The response is then unmarshalled into
+// the resp argument.
+func rpcCall(call *methodCall, resp response) error {
+	// marshal
+	b, err := xml.MarshalIndent(call, "", "  ")
+	if err != nil {
+		return fmt.Errorf("Gandi DNS: Marshal Error: %v", err)
+	}
+	// post
+	b = append([]byte(`<?xml version="1.0"?>`+"\n"), b...)
+	respBody, err := httpPost(endpoint, "text/xml", bytes.NewReader(b))
+	if err != nil {
+		return err
+	}
+	// unmarshal
+	err = xml.Unmarshal(respBody, resp)
+	if err != nil {
+		return fmt.Errorf("Gandi DNS: Unmarshal Error: %v", err)
+	}
+	if resp.faultCode() != 0 {
+		return rpcError{
+			faultCode: resp.faultCode(), faultString: resp.faultString()}
+	}
+	return nil
+}
+
+// functions to perform API actions
+
+func (d *DNSProvider) getZoneID(domain string) (int, error) {
+	resp := &responseStruct{}
+	err := rpcCall(&methodCall{
+		MethodName: "domain.info",
+		Params: []param{
+			paramString{Value: d.apiKey},
+			paramString{Value: domain},
+		},
+	}, resp)
+	if err != nil {
+		return 0, err
+	}
+	var zoneID int
+	for _, member := range resp.StructMembers {
+		if member.Name == "zone_id" {
+			zoneID = member.ValueInt
+		}
+	}
+	if zoneID == 0 {
+		return 0, fmt.Errorf(
+			"Gandi DNS: Could not determine zone_id for %s", domain)
+	}
+	return zoneID, nil
+}
+
+func (d *DNSProvider) cloneZone(zoneID int, name string) (int, error) {
+	resp := &responseStruct{}
+	err := rpcCall(&methodCall{
+		MethodName: "domain.zone.clone",
+		Params: []param{
+			paramString{Value: d.apiKey},
+			paramInt{Value: zoneID},
+			paramInt{Value: 0},
+			paramStruct{
+				StructMembers: []structMember{
+					structMemberString{
+						Name:  "name",
+						Value: name,
+					}},
+			},
+		},
+	}, resp)
+	if err != nil {
+		return 0, err
+	}
+	var newZoneID int
+	for _, member := range resp.StructMembers {
+		if member.Name == "id" {
+			newZoneID = member.ValueInt
+		}
+	}
+	if newZoneID == 0 {
+		return 0, fmt.Errorf("Gandi DNS: Could not determine cloned zone_id")
+	}
+	return newZoneID, nil
+}
+
+func (d *DNSProvider) newZoneVersion(zoneID int) (int, error) {
+	resp := &responseInt{}
+	err := rpcCall(&methodCall{
+		MethodName: "domain.zone.version.new",
+		Params: []param{
+			paramString{Value: d.apiKey},
+			paramInt{Value: zoneID},
+		},
+	}, resp)
+	if err != nil {
+		return 0, err
+	}
+	if resp.Value == 0 {
+		return 0, fmt.Errorf("Gandi DNS: Could not create new zone version")
+	}
+	return resp.Value, nil
+}
+
+func (d *DNSProvider) addTXTRecord(zoneID int, version int, name string, value string, ttl int) error {
+	resp := &responseStruct{}
+	err := rpcCall(&methodCall{
+		MethodName: "domain.zone.record.add",
+		Params: []param{
+			paramString{Value: d.apiKey},
+			paramInt{Value: zoneID},
+			paramInt{Value: version},
+			paramStruct{
+				StructMembers: []structMember{
+					structMemberString{
+						Name:  "type",
+						Value: "TXT",
+					}, structMemberString{
+						Name:  "name",
+						Value: name,
+					}, structMemberString{
+						Name:  "value",
+						Value: value,
+					}, structMemberInt{
+						Name:  "ttl",
+						Value: ttl,
+					}},
+			},
+		},
+	}, resp)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (d *DNSProvider) setZoneVersion(zoneID int, version int) error {
+	resp := &responseBool{}
+	err := rpcCall(&methodCall{
+		MethodName: "domain.zone.version.set",
+		Params: []param{
+			paramString{Value: d.apiKey},
+			paramInt{Value: zoneID},
+			paramInt{Value: version},
+		},
+	}, resp)
+	if err != nil {
+		return err
+	}
+	if !resp.Value {
+		return fmt.Errorf("Gandi DNS: could not set zone version")
+	}
+	return nil
+}
+
+func (d *DNSProvider) setZone(domain string, zoneID int) error {
+	resp := &responseStruct{}
+	err := rpcCall(&methodCall{
+		MethodName: "domain.zone.set",
+		Params: []param{
+			paramString{Value: d.apiKey},
+			paramString{Value: domain},
+			paramInt{Value: zoneID},
+		},
+	}, resp)
+	if err != nil {
+		return err
+	}
+	var respZoneID int
+	for _, member := range resp.StructMembers {
+		if member.Name == "zone_id" {
+			respZoneID = member.ValueInt
+		}
+	}
+	if respZoneID != zoneID {
+		return fmt.Errorf(
+			"Gandi DNS: Could not set new zone_id for %s", domain)
+	}
+	return nil
+}
+
+func (d *DNSProvider) deleteZone(zoneID int) error {
+	resp := &responseBool{}
+	err := rpcCall(&methodCall{
+		MethodName: "domain.zone.delete",
+		Params: []param{
+			paramString{Value: d.apiKey},
+			paramInt{Value: zoneID},
+		},
+	}, resp)
+	if err != nil {
+		return err
+	}
+	if !resp.Value {
+		return fmt.Errorf("Gandi DNS: could not delete zone_id")
+	}
+	return nil
+}

vendor/github.com/xenolf/lego/providers/dns/googlecloud/googlecloud.go

@@ -0,0 +1,168 @@
+// Package googlecloud implements a DNS provider for solving the DNS-01
+// challenge using Google Cloud DNS.
+package googlecloud
+
+import (
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+
+	"golang.org/x/net/context"
+	"golang.org/x/oauth2/google"
+
+	"google.golang.org/api/dns/v1"
+)
+
+// DNSProvider is an implementation of the DNSProvider interface.
+type DNSProvider struct {
+	project string
+	client  *dns.Service
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for Google Cloud
+// DNS. Credentials must be passed in the environment variable: GCE_PROJECT.
+func NewDNSProvider() (*DNSProvider, error) {
+	project := os.Getenv("GCE_PROJECT")
+	return NewDNSProviderCredentials(project)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for Google Cloud DNS.
+func NewDNSProviderCredentials(project string) (*DNSProvider, error) {
+	if project == "" {
+		return nil, fmt.Errorf("Google Cloud project name missing")
+	}
+
+	client, err := google.DefaultClient(context.Background(), dns.NdevClouddnsReadwriteScope)
+	if err != nil {
+		return nil, fmt.Errorf("Unable to get Google Cloud client: %v", err)
+	}
+	svc, err := dns.New(client)
+	if err != nil {
+		return nil, fmt.Errorf("Unable to create Google Cloud DNS service: %v", err)
+	}
+	return &DNSProvider{
+		project: project,
+		client:  svc,
+	}, nil
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge.
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+
+	zone, err := c.getHostedZone(domain)
+	if err != nil {
+		return err
+	}
+
+	rec := &dns.ResourceRecordSet{
+		Name:    fqdn,
+		Rrdatas: []string{value},
+		Ttl:     int64(ttl),
+		Type:    "TXT",
+	}
+	change := &dns.Change{
+		Additions: []*dns.ResourceRecordSet{rec},
+	}
+
+	// Look for existing records.
+	list, err := c.client.ResourceRecordSets.List(c.project, zone).Name(fqdn).Type("TXT").Do()
+	if err != nil {
+		return err
+	}
+	if len(list.Rrsets) > 0 {
+		// Attempt to delete the existing records when adding our new one.
+		change.Deletions = list.Rrsets
+	}
+
+	chg, err := c.client.Changes.Create(c.project, zone, change).Do()
+	if err != nil {
+		return err
+	}
+
+	// wait for change to be acknowledged
+	for chg.Status == "pending" {
+		time.Sleep(time.Second)
+
+		chg, err = c.client.Changes.Get(c.project, zone, chg.Id).Do()
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters.
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	zone, err := c.getHostedZone(domain)
+	if err != nil {
+		return err
+	}
+
+	records, err := c.findTxtRecords(zone, fqdn)
+	if err != nil {
+		return err
+	}
+
+	for _, rec := range records {
+		change := &dns.Change{
+			Deletions: []*dns.ResourceRecordSet{rec},
+		}
+		_, err = c.client.Changes.Create(c.project, zone, change).Do()
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Timeout customizes the timeout values used by the ACME package for checking
+// DNS record validity.
+func (c *DNSProvider) Timeout() (timeout, interval time.Duration) {
+	return 180 * time.Second, 5 * time.Second
+}
+
+// getHostedZone returns the managed-zone
+func (c *DNSProvider) getHostedZone(domain string) (string, error) {
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return "", err
+	}
+
+	zones, err := c.client.ManagedZones.
+		List(c.project).
+		DnsName(authZone).
+		Do()
+	if err != nil {
+		return "", fmt.Errorf("GoogleCloud API call failed: %v", err)
+	}
+
+	if len(zones.ManagedZones) == 0 {
+		return "", fmt.Errorf("No matching GoogleCloud domain found for domain %s", authZone)
+	}
+
+	return zones.ManagedZones[0].Name, nil
+}
+
+func (c *DNSProvider) findTxtRecords(zone, fqdn string) ([]*dns.ResourceRecordSet, error) {
+
+	recs, err := c.client.ResourceRecordSets.List(c.project, zone).Do()
+	if err != nil {
+		return nil, err
+	}
+
+	found := []*dns.ResourceRecordSet{}
+	for _, r := range recs.Rrsets {
+		if r.Type == "TXT" && r.Name == fqdn {
+			found = append(found, r)
+		}
+	}
+
+	return found, nil
+}

vendor/github.com/xenolf/lego/providers/dns/linode/linode.go

@@ -0,0 +1,131 @@
+// Package linode implements a DNS provider for solving the DNS-01 challenge
+// using Linode DNS.
+package linode
+
+import (
+	"errors"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/timewasted/linode/dns"
+	"github.com/xenolf/lego/acme"
+)
+
+const (
+	dnsMinTTLSecs      = 300
+	dnsUpdateFreqMins  = 15
+	dnsUpdateFudgeSecs = 120
+)
+
+type hostedZoneInfo struct {
+	domainId     int
+	resourceName string
+}
+
+// DNSProvider implements the acme.ChallengeProvider interface.
+type DNSProvider struct {
+	linode *dns.DNS
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for Linode.
+// Credentials must be passed in the environment variable: LINODE_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	apiKey := os.Getenv("LINODE_API_KEY")
+	return NewDNSProviderCredentials(apiKey)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for Linode.
+func NewDNSProviderCredentials(apiKey string) (*DNSProvider, error) {
+	if len(apiKey) == 0 {
+		return nil, errors.New("Linode credentials missing")
+	}
+
+	return &DNSProvider{
+		linode: dns.New(apiKey),
+	}, nil
+}
+
+// Timeout returns the timeout and interval to use when checking for DNS
+// propagation.  Adjusting here to cope with spikes in propagation times.
+func (p *DNSProvider) Timeout() (timeout, interval time.Duration) {
+	// Since Linode only updates their zone files every X minutes, we need
+	// to figure out how many minutes we have to wait until we hit the next
+	// interval of X.  We then wait another couple of minutes, just to be
+	// safe.  Hopefully at some point during all of this, the record will
+	// have propagated throughout Linode's network.
+	minsRemaining := dnsUpdateFreqMins - (time.Now().Minute() % dnsUpdateFreqMins)
+
+	timeout = (time.Duration(minsRemaining) * time.Minute) +
+		(dnsMinTTLSecs * time.Second) +
+		(dnsUpdateFudgeSecs * time.Second)
+	interval = 15 * time.Second
+	return
+}
+
+// Present creates a TXT record using the specified parameters.
+func (p *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+	zone, err := p.getHostedZoneInfo(fqdn)
+	if err != nil {
+		return err
+	}
+
+	if _, err = p.linode.CreateDomainResourceTXT(zone.domainId, acme.UnFqdn(fqdn), value, 60); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters.
+func (p *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+	zone, err := p.getHostedZoneInfo(fqdn)
+	if err != nil {
+		return err
+	}
+
+	// Get all TXT records for the specified domain.
+	resources, err := p.linode.GetResourcesByType(zone.domainId, "TXT")
+	if err != nil {
+		return err
+	}
+
+	// Remove the specified resource, if it exists.
+	for _, resource := range resources {
+		if resource.Name == zone.resourceName && resource.Target == value {
+			resp, err := p.linode.DeleteDomainResource(resource.DomainID, resource.ResourceID)
+			if err != nil {
+				return err
+			}
+			if resp.ResourceID != resource.ResourceID {
+				return errors.New("Error deleting resource: resource IDs do not match!")
+			}
+			break
+		}
+	}
+
+	return nil
+}
+
+func (p *DNSProvider) getHostedZoneInfo(fqdn string) (*hostedZoneInfo, error) {
+	// Lookup the zone that handles the specified FQDN.
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return nil, err
+	}
+	resourceName := strings.TrimSuffix(fqdn, "."+authZone)
+
+	// Query the authority zone.
+	domain, err := p.linode.GetDomain(acme.UnFqdn(authZone))
+	if err != nil {
+		return nil, err
+	}
+
+	return &hostedZoneInfo{
+		domainId:     domain.DomainID,
+		resourceName: resourceName,
+	}, nil
+}

vendor/github.com/xenolf/lego/providers/dns/namecheap/namecheap.go

@@ -0,0 +1,416 @@
+// Package namecheap implements a DNS provider for solving the DNS-01
+// challenge using namecheap DNS.
+package namecheap
+
+import (
+	"encoding/xml"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+)
+
+// Notes about namecheap's tool API:
+// 1. Using the API requires registration. Once registered, use your account
+//    name and API key to access the API.
+// 2. There is no API to add or modify a single DNS record. Instead you must
+//    read the entire list of records, make modifications, and then write the
+//    entire updated list of records.  (Yuck.)
+// 3. Namecheap's DNS updates can be slow to propagate. I've seen them take
+//    as long as an hour.
+// 4. Namecheap requires you to whitelist the IP address from which you call
+//    its APIs. It also requires all API calls to include the whitelisted IP
+//    address as a form or query string value. This code uses a namecheap
+//    service to query the client's IP address.
+
+var (
+	debug          = false
+	defaultBaseURL = "https://api.namecheap.com/xml.response"
+	getIPURL       = "https://dynamicdns.park-your-domain.com/getip"
+	httpClient     = http.Client{Timeout: 60 * time.Second}
+)
+
+// DNSProvider is an implementation of the ChallengeProviderTimeout interface
+// that uses Namecheap's tool API to manage TXT records for a domain.
+type DNSProvider struct {
+	baseURL  string
+	apiUser  string
+	apiKey   string
+	clientIP string
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for namecheap.
+// Credentials must be passed in the environment variables: NAMECHEAP_API_USER
+// and NAMECHEAP_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	apiUser := os.Getenv("NAMECHEAP_API_USER")
+	apiKey := os.Getenv("NAMECHEAP_API_KEY")
+	return NewDNSProviderCredentials(apiUser, apiKey)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for namecheap.
+func NewDNSProviderCredentials(apiUser, apiKey string) (*DNSProvider, error) {
+	if apiUser == "" || apiKey == "" {
+		return nil, fmt.Errorf("Namecheap credentials missing")
+	}
+
+	clientIP, err := getClientIP()
+	if err != nil {
+		return nil, err
+	}
+
+	return &DNSProvider{
+		baseURL:  defaultBaseURL,
+		apiUser:  apiUser,
+		apiKey:   apiKey,
+		clientIP: clientIP,
+	}, nil
+}
+
+// Timeout returns the timeout and interval to use when checking for DNS
+// propagation. Namecheap can sometimes take a long time to complete an
+// update, so wait up to 60 minutes for the update to propagate.
+func (d *DNSProvider) Timeout() (timeout, interval time.Duration) {
+	return 60 * time.Minute, 15 * time.Second
+}
+
+// host describes a DNS record returned by the Namecheap DNS gethosts API.
+// Namecheap uses the term "host" to refer to all DNS records that include
+// a host field (A, AAAA, CNAME, NS, TXT, URL).
+type host struct {
+	Type    string `xml:",attr"`
+	Name    string `xml:",attr"`
+	Address string `xml:",attr"`
+	MXPref  string `xml:",attr"`
+	TTL     string `xml:",attr"`
+}
+
+// apierror describes an error record in a namecheap API response.
+type apierror struct {
+	Number      int    `xml:",attr"`
+	Description string `xml:",innerxml"`
+}
+
+// getClientIP returns the client's public IP address. It uses namecheap's
+// IP discovery service to perform the lookup.
+func getClientIP() (addr string, err error) {
+	resp, err := httpClient.Get(getIPURL)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+
+	clientIP, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return "", err
+	}
+
+	if debug {
+		fmt.Println("Client IP:", string(clientIP))
+	}
+	return string(clientIP), nil
+}
+
+// A challenge repesents all the data needed to specify a dns-01 challenge
+// to lets-encrypt.
+type challenge struct {
+	domain   string
+	key      string
+	keyFqdn  string
+	keyValue string
+	tld      string
+	sld      string
+	host     string
+}
+
+// newChallenge builds a challenge record from a domain name, a challenge
+// authentication key, and a map of available TLDs.
+func newChallenge(domain, keyAuth string, tlds map[string]string) (*challenge, error) {
+	domain = acme.UnFqdn(domain)
+	parts := strings.Split(domain, ".")
+
+	// Find the longest matching TLD.
+	longest := -1
+	for i := len(parts); i > 0; i-- {
+		t := strings.Join(parts[i-1:], ".")
+		if _, found := tlds[t]; found {
+			longest = i - 1
+		}
+	}
+	if longest < 1 {
+		return nil, fmt.Errorf("Invalid domain name '%s'", domain)
+	}
+
+	tld := strings.Join(parts[longest:], ".")
+	sld := parts[longest-1]
+
+	var host string
+	if longest >= 1 {
+		host = strings.Join(parts[:longest-1], ".")
+	}
+
+	key, keyValue, _ := acme.DNS01Record(domain, keyAuth)
+
+	return &challenge{
+		domain:   domain,
+		key:      "_acme-challenge." + host,
+		keyFqdn:  key,
+		keyValue: keyValue,
+		tld:      tld,
+		sld:      sld,
+		host:     host,
+	}, nil
+}
+
+// setGlobalParams adds the namecheap global parameters to the provided url
+// Values record.
+func (d *DNSProvider) setGlobalParams(v *url.Values, cmd string) {
+	v.Set("ApiUser", d.apiUser)
+	v.Set("ApiKey", d.apiKey)
+	v.Set("UserName", d.apiUser)
+	v.Set("ClientIp", d.clientIP)
+	v.Set("Command", cmd)
+}
+
+// getTLDs requests the list of available TLDs from namecheap.
+func (d *DNSProvider) getTLDs() (tlds map[string]string, err error) {
+	values := make(url.Values)
+	d.setGlobalParams(&values, "namecheap.domains.getTldList")
+
+	reqURL, _ := url.Parse(d.baseURL)
+	reqURL.RawQuery = values.Encode()
+
+	resp, err := httpClient.Get(reqURL.String())
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		return nil, fmt.Errorf("getHosts HTTP error %d", resp.StatusCode)
+	}
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	type GetTldsResponse struct {
+		XMLName xml.Name   `xml:"ApiResponse"`
+		Errors  []apierror `xml:"Errors>Error"`
+		Result  []struct {
+			Name string `xml:",attr"`
+		} `xml:"CommandResponse>Tlds>Tld"`
+	}
+
+	var gtr GetTldsResponse
+	if err := xml.Unmarshal(body, &gtr); err != nil {
+		return nil, err
+	}
+	if len(gtr.Errors) > 0 {
+		return nil, fmt.Errorf("Namecheap error: %s [%d]",
+			gtr.Errors[0].Description, gtr.Errors[0].Number)
+	}
+
+	tlds = make(map[string]string)
+	for _, t := range gtr.Result {
+		tlds[t.Name] = t.Name
+	}
+	return tlds, nil
+}
+
+// getHosts reads the full list of DNS host records using the Namecheap API.
+func (d *DNSProvider) getHosts(ch *challenge) (hosts []host, err error) {
+	values := make(url.Values)
+	d.setGlobalParams(&values, "namecheap.domains.dns.getHosts")
+	values.Set("SLD", ch.sld)
+	values.Set("TLD", ch.tld)
+
+	reqURL, _ := url.Parse(d.baseURL)
+	reqURL.RawQuery = values.Encode()
+
+	resp, err := httpClient.Get(reqURL.String())
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		return nil, fmt.Errorf("getHosts HTTP error %d", resp.StatusCode)
+	}
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	type GetHostsResponse struct {
+		XMLName xml.Name   `xml:"ApiResponse"`
+		Status  string     `xml:"Status,attr"`
+		Errors  []apierror `xml:"Errors>Error"`
+		Hosts   []host     `xml:"CommandResponse>DomainDNSGetHostsResult>host"`
+	}
+
+	var ghr GetHostsResponse
+	if err = xml.Unmarshal(body, &ghr); err != nil {
+		return nil, err
+	}
+	if len(ghr.Errors) > 0 {
+		return nil, fmt.Errorf("Namecheap error: %s [%d]",
+			ghr.Errors[0].Description, ghr.Errors[0].Number)
+	}
+
+	return ghr.Hosts, nil
+}
+
+// setHosts writes the full list of DNS host records using the Namecheap API.
+func (d *DNSProvider) setHosts(ch *challenge, hosts []host) error {
+	values := make(url.Values)
+	d.setGlobalParams(&values, "namecheap.domains.dns.setHosts")
+	values.Set("SLD", ch.sld)
+	values.Set("TLD", ch.tld)
+
+	for i, h := range hosts {
+		ind := fmt.Sprintf("%d", i+1)
+		values.Add("HostName"+ind, h.Name)
+		values.Add("RecordType"+ind, h.Type)
+		values.Add("Address"+ind, h.Address)
+		values.Add("MXPref"+ind, h.MXPref)
+		values.Add("TTL"+ind, h.TTL)
+	}
+
+	resp, err := httpClient.PostForm(d.baseURL, values)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		return fmt.Errorf("setHosts HTTP error %d", resp.StatusCode)
+	}
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return err
+	}
+
+	type SetHostsResponse struct {
+		XMLName xml.Name   `xml:"ApiResponse"`
+		Status  string     `xml:"Status,attr"`
+		Errors  []apierror `xml:"Errors>Error"`
+		Result  struct {
+			IsSuccess string `xml:",attr"`
+		} `xml:"CommandResponse>DomainDNSSetHostsResult"`
+	}
+
+	var shr SetHostsResponse
+	if err := xml.Unmarshal(body, &shr); err != nil {
+		return err
+	}
+	if len(shr.Errors) > 0 {
+		return fmt.Errorf("Namecheap error: %s [%d]",
+			shr.Errors[0].Description, shr.Errors[0].Number)
+	}
+	if shr.Result.IsSuccess != "true" {
+		return fmt.Errorf("Namecheap setHosts failed.")
+	}
+
+	return nil
+}
+
+// addChallengeRecord adds a DNS challenge TXT record to a list of namecheap
+// host records.
+func (d *DNSProvider) addChallengeRecord(ch *challenge, hosts *[]host) {
+	host := host{
+		Name:    ch.key,
+		Type:    "TXT",
+		Address: ch.keyValue,
+		MXPref:  "10",
+		TTL:     "120",
+	}
+
+	// If there's already a TXT record with the same name, replace it.
+	for i, h := range *hosts {
+		if h.Name == ch.key && h.Type == "TXT" {
+			(*hosts)[i] = host
+			return
+		}
+	}
+
+	// No record was replaced, so add a new one.
+	*hosts = append(*hosts, host)
+}
+
+// removeChallengeRecord removes a DNS challenge TXT record from a list of
+// namecheap host records. Return true if a record was removed.
+func (d *DNSProvider) removeChallengeRecord(ch *challenge, hosts *[]host) bool {
+	// Find the challenge TXT record and remove it if found.
+	for i, h := range *hosts {
+		if h.Name == ch.key && h.Type == "TXT" {
+			*hosts = append((*hosts)[:i], (*hosts)[i+1:]...)
+			return true
+		}
+	}
+
+	return false
+}
+
+// Present installs a TXT record for the DNS challenge.
+func (d *DNSProvider) Present(domain, token, keyAuth string) error {
+	tlds, err := d.getTLDs()
+	if err != nil {
+		return err
+	}
+
+	ch, err := newChallenge(domain, keyAuth, tlds)
+	if err != nil {
+		return err
+	}
+
+	hosts, err := d.getHosts(ch)
+	if err != nil {
+		return err
+	}
+
+	d.addChallengeRecord(ch, &hosts)
+
+	if debug {
+		for _, h := range hosts {
+			fmt.Printf(
+				"%-5.5s %-30.30s %-6s %-70.70s\n",
+				h.Type, h.Name, h.TTL, h.Address)
+		}
+	}
+
+	return d.setHosts(ch, hosts)
+}
+
+// CleanUp removes a TXT record used for a previous DNS challenge.
+func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	tlds, err := d.getTLDs()
+	if err != nil {
+		return err
+	}
+
+	ch, err := newChallenge(domain, keyAuth, tlds)
+	if err != nil {
+		return err
+	}
+
+	hosts, err := d.getHosts(ch)
+	if err != nil {
+		return err
+	}
+
+	if removed := d.removeChallengeRecord(ch, &hosts); !removed {
+		return nil
+	}
+
+	return d.setHosts(ch, hosts)
+}

vendor/github.com/xenolf/lego/providers/dns/ns1/ns1.go

@@ -0,0 +1,97 @@
+// Package ns1 implements a DNS provider for solving the DNS-01 challenge
+// using NS1 DNS.
+package ns1
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+	"gopkg.in/ns1/ns1-go.v2/rest"
+	"gopkg.in/ns1/ns1-go.v2/rest/model/dns"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface.
+type DNSProvider struct {
+	client *rest.Client
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for NS1.
+// Credentials must be passed in the environment variables: NS1_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	key := os.Getenv("NS1_API_KEY")
+	if key == "" {
+		return nil, fmt.Errorf("NS1 credentials missing")
+	}
+	return NewDNSProviderCredentials(key)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for NS1.
+func NewDNSProviderCredentials(key string) (*DNSProvider, error) {
+	if key == "" {
+		return nil, fmt.Errorf("NS1 credentials missing")
+	}
+
+	httpClient := &http.Client{Timeout: time.Second * 10}
+	client := rest.NewClient(httpClient, rest.SetAPIKey(key))
+
+	return &DNSProvider{client}, nil
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge.
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+
+	zone, err := c.getHostedZone(domain)
+	if err != nil {
+		return err
+	}
+
+	record := c.newTxtRecord(zone, fqdn, value, ttl)
+	_, err = c.client.Records.Create(record)
+	if err != nil && err != rest.ErrRecordExists {
+		return err
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters.
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	zone, err := c.getHostedZone(domain)
+	if err != nil {
+		return err
+	}
+
+	name := acme.UnFqdn(fqdn)
+	_, err = c.client.Records.Delete(zone.Zone, name, "TXT")
+	return err
+}
+
+func (c *DNSProvider) getHostedZone(domain string) (*dns.Zone, error) {
+	zone, _, err := c.client.Zones.Get(domain)
+	if err != nil {
+		return nil, err
+	}
+
+	return zone, nil
+}
+
+func (c *DNSProvider) newTxtRecord(zone *dns.Zone, fqdn, value string, ttl int) *dns.Record {
+	name := acme.UnFqdn(fqdn)
+
+	return &dns.Record{
+		Type:   "TXT",
+		Zone:   zone.Zone,
+		Domain: name,
+		TTL:    ttl,
+		Answers: []*dns.Answer{
+			{Rdata: []string{value}},
+		},
+	}
+}

vendor/github.com/xenolf/lego/providers/dns/ovh/ovh.go

@@ -0,0 +1,159 @@
+// Package OVH implements a DNS provider for solving the DNS-01
+// challenge using OVH DNS.
+package ovh
+
+import (
+	"fmt"
+	"os"
+	"strings"
+	"sync"
+
+	"github.com/ovh/go-ovh/ovh"
+	"github.com/xenolf/lego/acme"
+)
+
+// OVH API reference:       https://eu.api.ovh.com/
+// Create a Token:					https://eu.api.ovh.com/createToken/
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface
+// that uses OVH's REST API to manage TXT records for a domain.
+type DNSProvider struct {
+	client      *ovh.Client
+	recordIDs   map[string]int
+	recordIDsMu sync.Mutex
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for OVH
+// Credentials must be passed in the environment variable:
+// OVH_ENDPOINT : it must be ovh-eu or ovh-ca
+// OVH_APPLICATION_KEY
+// OVH_APPLICATION_SECRET
+// OVH_CONSUMER_KEY
+func NewDNSProvider() (*DNSProvider, error) {
+	apiEndpoint := os.Getenv("OVH_ENDPOINT")
+	applicationKey := os.Getenv("OVH_APPLICATION_KEY")
+	applicationSecret := os.Getenv("OVH_APPLICATION_SECRET")
+	consumerKey := os.Getenv("OVH_CONSUMER_KEY")
+	return NewDNSProviderCredentials(apiEndpoint, applicationKey, applicationSecret, consumerKey)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for OVH.
+func NewDNSProviderCredentials(apiEndpoint, applicationKey, applicationSecret, consumerKey string) (*DNSProvider, error) {
+	if apiEndpoint == "" || applicationKey == "" || applicationSecret == "" || consumerKey == "" {
+		return nil, fmt.Errorf("OVH credentials missing")
+	}
+
+	ovhClient, _ := ovh.NewClient(
+		apiEndpoint,
+		applicationKey,
+		applicationSecret,
+		consumerKey,
+	)
+
+	return &DNSProvider{
+		client:    ovhClient,
+		recordIDs: make(map[string]int),
+	}, nil
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge.
+func (d *DNSProvider) Present(domain, token, keyAuth string) error {
+
+	// txtRecordRequest represents the request body to DO's API to make a TXT record
+	type txtRecordRequest struct {
+		FieldType string `json:"fieldType"`
+		SubDomain string `json:"subDomain"`
+		Target    string `json:"target"`
+		TTL       int    `json:"ttl"`
+	}
+
+	// txtRecordResponse represents a response from DO's API after making a TXT record
+	type txtRecordResponse struct {
+		ID        int    `json:"id"`
+		FieldType string `json:"fieldType"`
+		SubDomain string `json:"subDomain"`
+		Target    string `json:"target"`
+		TTL       int    `json:"ttl"`
+		Zone      string `json:"zone"`
+	}
+
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+
+	// Parse domain name
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return fmt.Errorf("Could not determine zone for domain: '%s'. %s", domain, err)
+	}
+
+	authZone = acme.UnFqdn(authZone)
+	subDomain := d.extractRecordName(fqdn, authZone)
+
+	reqURL := fmt.Sprintf("/domain/zone/%s/record", authZone)
+	reqData := txtRecordRequest{FieldType: "TXT", SubDomain: subDomain, Target: value, TTL: ttl}
+	var respData txtRecordResponse
+
+	// Create TXT record
+	err = d.client.Post(reqURL, reqData, &respData)
+	if err != nil {
+		fmt.Printf("Error when call OVH api to add record : %q \n", err)
+		return err
+	}
+
+	// Apply the change
+	reqURL = fmt.Sprintf("/domain/zone/%s/refresh", authZone)
+	err = d.client.Post(reqURL, nil, nil)
+	if err != nil {
+		fmt.Printf("Error when call OVH api to refresh zone : %q \n", err)
+		return err
+	}
+
+	d.recordIDsMu.Lock()
+	d.recordIDs[fqdn] = respData.ID
+	d.recordIDsMu.Unlock()
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	// get the record's unique ID from when we created it
+	d.recordIDsMu.Lock()
+	recordID, ok := d.recordIDs[fqdn]
+	d.recordIDsMu.Unlock()
+	if !ok {
+		return fmt.Errorf("unknown record ID for '%s'", fqdn)
+	}
+
+	authZone, err := acme.FindZoneByFqdn(acme.ToFqdn(domain), acme.RecursiveNameservers)
+	if err != nil {
+		return fmt.Errorf("Could not determine zone for domain: '%s'. %s", domain, err)
+	}
+
+	authZone = acme.UnFqdn(authZone)
+
+	reqURL := fmt.Sprintf("/domain/zone/%s/record/%d", authZone, recordID)
+
+	err = d.client.Delete(reqURL, nil)
+	if err != nil {
+		fmt.Printf("Error when call OVH api to delete challenge record : %q \n", err)
+		return err
+	}
+
+	// Delete record ID from map
+	d.recordIDsMu.Lock()
+	delete(d.recordIDs, fqdn)
+	d.recordIDsMu.Unlock()
+
+	return nil
+}
+
+func (d *DNSProvider) extractRecordName(fqdn, domain string) string {
+	name := acme.UnFqdn(fqdn)
+	if idx := strings.Index(name, "."+domain); idx != -1 {
+		return name[:idx]
+	}
+	return name
+}

vendor/github.com/xenolf/lego/providers/dns/pdns/pdns.go

@@ -0,0 +1,343 @@
+// Package pdns implements a DNS provider for solving the DNS-01
+// challenge using PowerDNS nameserver.
+package pdns
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface
+type DNSProvider struct {
+	apiKey     string
+	host       *url.URL
+	apiVersion int
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for pdns.
+// Credentials must be passed in the environment variable:
+// PDNS_API_URL and PDNS_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	key := os.Getenv("PDNS_API_KEY")
+	hostUrl, err := url.Parse(os.Getenv("PDNS_API_URL"))
+	if err != nil {
+		return nil, err
+	}
+
+	return NewDNSProviderCredentials(hostUrl, key)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for pdns.
+func NewDNSProviderCredentials(host *url.URL, key string) (*DNSProvider, error) {
+	if key == "" {
+		return nil, fmt.Errorf("PDNS API key missing")
+	}
+
+	if host == nil || host.Host == "" {
+		return nil, fmt.Errorf("PDNS API URL missing")
+	}
+
+	provider := &DNSProvider{
+		host:   host,
+		apiKey: key,
+	}
+	provider.getAPIVersion()
+
+	return provider, nil
+}
+
+// Timeout returns the timeout and interval to use when checking for DNS
+// propagation. Adjusting here to cope with spikes in propagation times.
+func (c *DNSProvider) Timeout() (timeout, interval time.Duration) {
+	return 120 * time.Second, 2 * time.Second
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+	zone, err := c.getHostedZone(fqdn)
+	if err != nil {
+		return err
+	}
+
+	name := fqdn
+
+	// pre-v1 API wants non-fqdn
+	if c.apiVersion == 0 {
+		name = acme.UnFqdn(fqdn)
+	}
+
+	rec := pdnsRecord{
+		Content:  "\"" + value + "\"",
+		Disabled: false,
+
+		// pre-v1 API
+		Type: "TXT",
+		Name: name,
+		TTL:  120,
+	}
+
+	rrsets := rrSets{
+		RRSets: []rrSet{
+			rrSet{
+				Name:       name,
+				ChangeType: "REPLACE",
+				Type:       "TXT",
+				Kind:       "Master",
+				TTL:        120,
+				Records:    []pdnsRecord{rec},
+			},
+		},
+	}
+
+	body, err := json.Marshal(rrsets)
+	if err != nil {
+		return err
+	}
+
+	_, err = c.makeRequest("PATCH", zone.URL, bytes.NewReader(body))
+	if err != nil {
+		fmt.Println("here")
+		return err
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	zone, err := c.getHostedZone(fqdn)
+	if err != nil {
+		return err
+	}
+
+	set, err := c.findTxtRecord(fqdn)
+	if err != nil {
+		return err
+	}
+
+	rrsets := rrSets{
+		RRSets: []rrSet{
+			rrSet{
+				Name:       set.Name,
+				Type:       set.Type,
+				ChangeType: "DELETE",
+			},
+		},
+	}
+	body, err := json.Marshal(rrsets)
+	if err != nil {
+		return err
+	}
+
+	_, err = c.makeRequest("PATCH", zone.URL, bytes.NewReader(body))
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (c *DNSProvider) getHostedZone(fqdn string) (*hostedZone, error) {
+	var zone hostedZone
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return nil, err
+	}
+
+	url := "/servers/localhost/zones"
+	result, err := c.makeRequest("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	zones := []hostedZone{}
+	err = json.Unmarshal(result, &zones)
+	if err != nil {
+		return nil, err
+	}
+
+	url = ""
+	for _, zone := range zones {
+		if acme.UnFqdn(zone.Name) == acme.UnFqdn(authZone) {
+			url = zone.URL
+		}
+	}
+
+	result, err = c.makeRequest("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	err = json.Unmarshal(result, &zone)
+	if err != nil {
+		return nil, err
+	}
+
+	// convert pre-v1 API result
+	if len(zone.Records) > 0 {
+		zone.RRSets = []rrSet{}
+		for _, record := range zone.Records {
+			set := rrSet{
+				Name:    record.Name,
+				Type:    record.Type,
+				Records: []pdnsRecord{record},
+			}
+			zone.RRSets = append(zone.RRSets, set)
+		}
+	}
+
+	return &zone, nil
+}
+
+func (c *DNSProvider) findTxtRecord(fqdn string) (*rrSet, error) {
+	zone, err := c.getHostedZone(fqdn)
+	if err != nil {
+		return nil, err
+	}
+
+	_, err = c.makeRequest("GET", zone.URL, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, set := range zone.RRSets {
+		if (set.Name == acme.UnFqdn(fqdn) || set.Name == fqdn) && set.Type == "TXT" {
+			return &set, nil
+		}
+	}
+
+	return nil, fmt.Errorf("No existing record found for %s", fqdn)
+}
+
+func (c *DNSProvider) getAPIVersion() {
+	type APIVersion struct {
+		URL     string `json:"url"`
+		Version int    `json:"version"`
+	}
+
+	result, err := c.makeRequest("GET", "/api", nil)
+	if err != nil {
+		return
+	}
+
+	var versions []APIVersion
+	err = json.Unmarshal(result, &versions)
+	if err != nil {
+		return
+	}
+
+	latestVersion := 0
+	for _, v := range versions {
+		if v.Version > latestVersion {
+			latestVersion = v.Version
+		}
+	}
+	c.apiVersion = latestVersion
+}
+
+func (c *DNSProvider) makeRequest(method, uri string, body io.Reader) (json.RawMessage, error) {
+	type APIError struct {
+		Error string `json:"error"`
+	}
+	var path = ""
+	if c.host.Path != "/" {
+		path = c.host.Path
+	}
+	if c.apiVersion > 0 {
+		if !strings.HasPrefix(uri, "api/v") {
+			uri = "/api/v" + strconv.Itoa(c.apiVersion) + uri
+		} else {
+			uri = "/" + uri
+		}
+	}
+	url := c.host.Scheme + "://" + c.host.Host + path + uri
+	req, err := http.NewRequest(method, url, body)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Set("X-API-Key", c.apiKey)
+
+	client := http.Client{Timeout: 30 * time.Second}
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("Error talking to PDNS API -> %v", err)
+	}
+
+	defer resp.Body.Close()
+
+	if resp.StatusCode != 422 && (resp.StatusCode < 200 || resp.StatusCode >= 300) {
+		return nil, fmt.Errorf("Unexpected HTTP status code %d when fetching '%s'", resp.StatusCode, url)
+	}
+
+	var msg json.RawMessage
+	err = json.NewDecoder(resp.Body).Decode(&msg)
+	switch {
+	case err == io.EOF:
+		// empty body
+		return nil, nil
+	case err != nil:
+		// other error
+		return nil, err
+	}
+
+	// check for PowerDNS error message
+	if len(msg) > 0 && msg[0] == '{' {
+		var apiError APIError
+		err = json.Unmarshal(msg, &apiError)
+		if err != nil {
+			return nil, err
+		}
+		if apiError.Error != "" {
+			return nil, fmt.Errorf("Error talking to PDNS API -> %v", apiError.Error)
+		}
+	}
+	return msg, nil
+}
+
+type pdnsRecord struct {
+	Content  string `json:"content"`
+	Disabled bool   `json:"disabled"`
+
+	// pre-v1 API
+	Name string `json:"name"`
+	Type string `json:"type"`
+	TTL  int    `json:"ttl,omitempty"`
+}
+
+type hostedZone struct {
+	ID     string  `json:"id"`
+	Name   string  `json:"name"`
+	URL    string  `json:"url"`
+	RRSets []rrSet `json:"rrsets"`
+
+	// pre-v1 API
+	Records []pdnsRecord `json:"records"`
+}
+
+type rrSet struct {
+	Name       string       `json:"name"`
+	Type       string       `json:"type"`
+	Kind       string       `json:"kind"`
+	ChangeType string       `json:"changetype"`
+	Records    []pdnsRecord `json:"records"`
+	TTL        int          `json:"ttl,omitempty"`
+}
+
+type rrSets struct {
+	RRSets []rrSet `json:"rrsets"`
+}

vendor/github.com/xenolf/lego/providers/dns/rackspace/rackspace.go

@@ -0,0 +1,284 @@
+// Package rackspace implements a DNS provider for solving the DNS-01
+// challenge using rackspace DNS.
+package rackspace
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+)
+
+// rackspaceAPIURL represents the Identity API endpoint to call
+var rackspaceAPIURL = "https://identity.api.rackspacecloud.com/v2.0/tokens"
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface
+// used to store the reusable token and DNS API endpoint
+type DNSProvider struct {
+	token            string
+	cloudDNSEndpoint string
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for Rackspace.
+// Credentials must be passed in the environment variables: RACKSPACE_USER
+// and RACKSPACE_API_KEY.
+func NewDNSProvider() (*DNSProvider, error) {
+	user := os.Getenv("RACKSPACE_USER")
+	key := os.Getenv("RACKSPACE_API_KEY")
+	return NewDNSProviderCredentials(user, key)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for Rackspace. It authenticates against
+// the API, also grabbing the DNS Endpoint.
+func NewDNSProviderCredentials(user, key string) (*DNSProvider, error) {
+	if user == "" || key == "" {
+		return nil, fmt.Errorf("Rackspace credentials missing")
+	}
+
+	type APIKeyCredentials struct {
+		Username string `json:"username"`
+		APIKey   string `json:"apiKey"`
+	}
+
+	type Auth struct {
+		APIKeyCredentials `json:"RAX-KSKEY:apiKeyCredentials"`
+	}
+
+	type RackspaceAuthData struct {
+		Auth `json:"auth"`
+	}
+
+	type RackspaceIdentity struct {
+		Access struct {
+			ServiceCatalog []struct {
+				Endpoints []struct {
+					PublicURL string `json:"publicURL"`
+					TenantID  string `json:"tenantId"`
+				} `json:"endpoints"`
+				Name string `json:"name"`
+			} `json:"serviceCatalog"`
+			Token struct {
+				ID string `json:"id"`
+			} `json:"token"`
+		} `json:"access"`
+	}
+
+	authData := RackspaceAuthData{
+		Auth: Auth{
+			APIKeyCredentials: APIKeyCredentials{
+				Username: user,
+				APIKey:   key,
+			},
+		},
+	}
+
+	body, err := json.Marshal(authData)
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequest("POST", rackspaceAPIURL, bytes.NewReader(body))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+
+	client := http.Client{Timeout: 30 * time.Second}
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("Error querying Rackspace Identity API: %v", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("Rackspace Authentication failed. Response code: %d", resp.StatusCode)
+	}
+
+	var rackspaceIdentity RackspaceIdentity
+	err = json.NewDecoder(resp.Body).Decode(&rackspaceIdentity)
+	if err != nil {
+		return nil, err
+	}
+
+	// Iterate through the Service Catalog to get the DNS Endpoint
+	var dnsEndpoint string
+	for _, service := range rackspaceIdentity.Access.ServiceCatalog {
+		if service.Name == "cloudDNS" {
+			dnsEndpoint = service.Endpoints[0].PublicURL
+			break
+		}
+	}
+	if dnsEndpoint == "" {
+		return nil, fmt.Errorf("Failed to populate DNS endpoint, check Rackspace API for changes.")
+	}
+
+	return &DNSProvider{
+		token:            rackspaceIdentity.Access.Token.ID,
+		cloudDNSEndpoint: dnsEndpoint,
+	}, nil
+}
+
+// Present creates a TXT record to fulfil the dns-01 challenge
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+	zoneID, err := c.getHostedZoneID(fqdn)
+	if err != nil {
+		return err
+	}
+
+	rec := RackspaceRecords{
+		RackspaceRecord: []RackspaceRecord{{
+			Name: acme.UnFqdn(fqdn),
+			Type: "TXT",
+			Data: value,
+			TTL:  300,
+		}},
+	}
+
+	body, err := json.Marshal(rec)
+	if err != nil {
+		return err
+	}
+
+	_, err = c.makeRequest("POST", fmt.Sprintf("/domains/%d/records", zoneID), bytes.NewReader(body))
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+	zoneID, err := c.getHostedZoneID(fqdn)
+	if err != nil {
+		return err
+	}
+
+	record, err := c.findTxtRecord(fqdn, zoneID)
+	if err != nil {
+		return err
+	}
+
+	_, err = c.makeRequest("DELETE", fmt.Sprintf("/domains/%d/records?id=%s", zoneID, record.ID), nil)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// getHostedZoneID performs a lookup to get the DNS zone which needs
+// modifying for a given FQDN
+func (c *DNSProvider) getHostedZoneID(fqdn string) (int, error) {
+	// HostedZones represents the response when querying Rackspace DNS zones
+	type ZoneSearchResponse struct {
+		TotalEntries int `json:"totalEntries"`
+		HostedZones  []struct {
+			ID   int    `json:"id"`
+			Name string `json:"name"`
+		} `json:"domains"`
+	}
+
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return 0, err
+	}
+
+	result, err := c.makeRequest("GET", fmt.Sprintf("/domains?name=%s", acme.UnFqdn(authZone)), nil)
+	if err != nil {
+		return 0, err
+	}
+
+	var zoneSearchResponse ZoneSearchResponse
+	err = json.Unmarshal(result, &zoneSearchResponse)
+	if err != nil {
+		return 0, err
+	}
+
+	// If nothing was returned, or for whatever reason more than 1 was returned (the search uses exact match, so should not occur)
+	if zoneSearchResponse.TotalEntries != 1 {
+		return 0, fmt.Errorf("Found %d zones for %s in Rackspace for domain %s", zoneSearchResponse.TotalEntries, authZone, fqdn)
+	}
+
+	return zoneSearchResponse.HostedZones[0].ID, nil
+}
+
+// findTxtRecord searches a DNS zone for a TXT record with a specific name
+func (c *DNSProvider) findTxtRecord(fqdn string, zoneID int) (*RackspaceRecord, error) {
+	result, err := c.makeRequest("GET", fmt.Sprintf("/domains/%d/records?type=TXT&name=%s", zoneID, acme.UnFqdn(fqdn)), nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var records RackspaceRecords
+	err = json.Unmarshal(result, &records)
+	if err != nil {
+		return nil, err
+	}
+
+	recordsLength := len(records.RackspaceRecord)
+	switch recordsLength {
+	case 1:
+		break
+	case 0:
+		return nil, fmt.Errorf("No TXT record found for %s", fqdn)
+	default:
+		return nil, fmt.Errorf("More than 1 TXT record found for %s", fqdn)
+	}
+
+	return &records.RackspaceRecord[0], nil
+}
+
+// makeRequest is a wrapper function used for making DNS API requests
+func (c *DNSProvider) makeRequest(method, uri string, body io.Reader) (json.RawMessage, error) {
+	url := c.cloudDNSEndpoint + uri
+	req, err := http.NewRequest(method, url, body)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Set("X-Auth-Token", c.token)
+	req.Header.Set("Content-Type", "application/json")
+
+	client := http.Client{Timeout: 30 * time.Second}
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("Error querying DNS API: %v", err)
+	}
+
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusAccepted {
+		return nil, fmt.Errorf("Request failed for %s %s. Response code: %d", method, url, resp.StatusCode)
+	}
+
+	var r json.RawMessage
+	err = json.NewDecoder(resp.Body).Decode(&r)
+	if err != nil {
+		return nil, fmt.Errorf("JSON decode failed for %s %s. Response code: %d", method, url, resp.StatusCode)
+	}
+
+	return r, nil
+}
+
+// RackspaceRecords is the list of records sent/recieved from the DNS API
+type RackspaceRecords struct {
+	RackspaceRecord []RackspaceRecord `json:"records"`
+}
+
+// RackspaceRecord represents a Rackspace DNS record
+type RackspaceRecord struct {
+	Name string `json:"name"`
+	Type string `json:"type"`
+	Data string `json:"data"`
+	TTL  int    `json:"ttl,omitempty"`
+	ID   string `json:"id,omitempty"`
+}

vendor/github.com/xenolf/lego/providers/dns/rfc2136/rfc2136.go

@@ -0,0 +1,129 @@
+// Package rfc2136 implements a DNS provider for solving the DNS-01 challenge
+// using the rfc2136 dynamic update.
+package rfc2136
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/miekg/dns"
+	"github.com/xenolf/lego/acme"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface that
+// uses dynamic DNS updates (RFC 2136) to create TXT records on a nameserver.
+type DNSProvider struct {
+	nameserver    string
+	tsigAlgorithm string
+	tsigKey       string
+	tsigSecret    string
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for rfc2136
+// dynamic update. Credentials must be passed in the environment variables:
+// RFC2136_NAMESERVER, RFC2136_TSIG_ALGORITHM, RFC2136_TSIG_KEY and
+// RFC2136_TSIG_SECRET. To disable TSIG authentication, leave the TSIG
+// variables unset. RFC2136_NAMESERVER must be a network address in the form
+// "host" or "host:port".
+func NewDNSProvider() (*DNSProvider, error) {
+	nameserver := os.Getenv("RFC2136_NAMESERVER")
+	tsigAlgorithm := os.Getenv("RFC2136_TSIG_ALGORITHM")
+	tsigKey := os.Getenv("RFC2136_TSIG_KEY")
+	tsigSecret := os.Getenv("RFC2136_TSIG_SECRET")
+	return NewDNSProviderCredentials(nameserver, tsigAlgorithm, tsigKey, tsigSecret)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a
+// DNSProvider instance configured for rfc2136 dynamic update. To disable TSIG
+// authentication, leave the TSIG parameters as empty strings.
+// nameserver must be a network address in the form "host" or "host:port".
+func NewDNSProviderCredentials(nameserver, tsigAlgorithm, tsigKey, tsigSecret string) (*DNSProvider, error) {
+	if nameserver == "" {
+		return nil, fmt.Errorf("RFC2136 nameserver missing")
+	}
+
+	// Append the default DNS port if none is specified.
+	if _, _, err := net.SplitHostPort(nameserver); err != nil {
+		if strings.Contains(err.Error(), "missing port") {
+			nameserver = net.JoinHostPort(nameserver, "53")
+		} else {
+			return nil, err
+		}
+	}
+	d := &DNSProvider{
+		nameserver: nameserver,
+	}
+	if tsigAlgorithm == "" {
+		tsigAlgorithm = dns.HmacMD5
+	}
+	d.tsigAlgorithm = tsigAlgorithm
+	if len(tsigKey) > 0 && len(tsigSecret) > 0 {
+		d.tsigKey = tsigKey
+		d.tsigSecret = tsigSecret
+	}
+
+	return d, nil
+}
+
+// Present creates a TXT record using the specified parameters
+func (r *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+	return r.changeRecord("INSERT", fqdn, value, ttl)
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (r *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+	return r.changeRecord("REMOVE", fqdn, value, ttl)
+}
+
+func (r *DNSProvider) changeRecord(action, fqdn, value string, ttl int) error {
+	// Find the zone for the given fqdn
+	zone, err := acme.FindZoneByFqdn(fqdn, []string{r.nameserver})
+	if err != nil {
+		return err
+	}
+
+	// Create RR
+	rr := new(dns.TXT)
+	rr.Hdr = dns.RR_Header{Name: fqdn, Rrtype: dns.TypeTXT, Class: dns.ClassINET, Ttl: uint32(ttl)}
+	rr.Txt = []string{value}
+	rrs := []dns.RR{rr}
+
+	// Create dynamic update packet
+	m := new(dns.Msg)
+	m.SetUpdate(zone)
+	switch action {
+	case "INSERT":
+		// Always remove old challenge left over from who knows what.
+		m.RemoveRRset(rrs)
+		m.Insert(rrs)
+	case "REMOVE":
+		m.Remove(rrs)
+	default:
+		return fmt.Errorf("Unexpected action: %s", action)
+	}
+
+	// Setup client
+	c := new(dns.Client)
+	c.SingleInflight = true
+	// TSIG authentication / msg signing
+	if len(r.tsigKey) > 0 && len(r.tsigSecret) > 0 {
+		m.SetTsig(dns.Fqdn(r.tsigKey), r.tsigAlgorithm, 300, time.Now().Unix())
+		c.TsigSecret = map[string]string{dns.Fqdn(r.tsigKey): r.tsigSecret}
+	}
+
+	// Send the query
+	reply, _, err := c.Exchange(m, r.nameserver)
+	if err != nil {
+		return fmt.Errorf("DNS update failed: %v", err)
+	}
+	if reply != nil && reply.Rcode != dns.RcodeSuccess {
+		return fmt.Errorf("DNS update failed. Server replied: %s", dns.RcodeToString[reply.Rcode])
+	}
+
+	return nil
+}

vendor/github.com/xenolf/lego/providers/dns/route53/route53.go

@@ -0,0 +1,171 @@
+// Package route53 implements a DNS provider for solving the DNS-01 challenge
+// using AWS Route 53 DNS.
+package route53
+
+import (
+	"fmt"
+	"math/rand"
+	"strings"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/client"
+	"github.com/aws/aws-sdk-go/aws/request"
+	"github.com/aws/aws-sdk-go/aws/session"
+	"github.com/aws/aws-sdk-go/service/route53"
+	"github.com/xenolf/lego/acme"
+)
+
+const (
+	maxRetries = 5
+	route53TTL = 10
+)
+
+// DNSProvider implements the acme.ChallengeProvider interface
+type DNSProvider struct {
+	client *route53.Route53
+}
+
+// customRetryer implements the client.Retryer interface by composing the
+// DefaultRetryer. It controls the logic for retrying recoverable request
+// errors (e.g. when rate limits are exceeded).
+type customRetryer struct {
+	client.DefaultRetryer
+}
+
+// RetryRules overwrites the DefaultRetryer's method.
+// It uses a basic exponential backoff algorithm that returns an initial
+// delay of ~400ms with an upper limit of ~30 seconds which should prevent
+// causing a high number of consecutive throttling errors.
+// For reference: Route 53 enforces an account-wide(!) 5req/s query limit.
+func (d customRetryer) RetryRules(r *request.Request) time.Duration {
+	retryCount := r.RetryCount
+	if retryCount > 7 {
+		retryCount = 7
+	}
+
+	delay := (1 << uint(retryCount)) * (rand.Intn(50) + 200)
+	return time.Duration(delay) * time.Millisecond
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for the AWS
+// Route 53 service.
+//
+// AWS Credentials are automatically detected in the following locations
+// and prioritized in the following order:
+// 1. Environment variables: AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY,
+//    AWS_REGION, [AWS_SESSION_TOKEN]
+// 2. Shared credentials file (defaults to ~/.aws/credentials)
+// 3. Amazon EC2 IAM role
+//
+// See also: https://github.com/aws/aws-sdk-go/wiki/configuring-sdk
+func NewDNSProvider() (*DNSProvider, error) {
+	r := customRetryer{}
+	r.NumMaxRetries = maxRetries
+	config := request.WithRetryer(aws.NewConfig(), r)
+	client := route53.New(session.New(config))
+
+	return &DNSProvider{client: client}, nil
+}
+
+// Present creates a TXT record using the specified parameters
+func (r *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+	value = `"` + value + `"`
+	return r.changeRecord("UPSERT", fqdn, value, route53TTL)
+}
+
+// CleanUp removes the TXT record matching the specified parameters
+func (r *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+	value = `"` + value + `"`
+	return r.changeRecord("DELETE", fqdn, value, route53TTL)
+}
+
+func (r *DNSProvider) changeRecord(action, fqdn, value string, ttl int) error {
+	hostedZoneID, err := getHostedZoneID(fqdn, r.client)
+	if err != nil {
+		return fmt.Errorf("Failed to determine Route 53 hosted zone ID: %v", err)
+	}
+
+	recordSet := newTXTRecordSet(fqdn, value, ttl)
+	reqParams := &route53.ChangeResourceRecordSetsInput{
+		HostedZoneId: aws.String(hostedZoneID),
+		ChangeBatch: &route53.ChangeBatch{
+			Comment: aws.String("Managed by Lego"),
+			Changes: []*route53.Change{
+				{
+					Action:            aws.String(action),
+					ResourceRecordSet: recordSet,
+				},
+			},
+		},
+	}
+
+	resp, err := r.client.ChangeResourceRecordSets(reqParams)
+	if err != nil {
+		return fmt.Errorf("Failed to change Route 53 record set: %v", err)
+	}
+
+	statusID := resp.ChangeInfo.Id
+
+	return acme.WaitFor(120*time.Second, 4*time.Second, func() (bool, error) {
+		reqParams := &route53.GetChangeInput{
+			Id: statusID,
+		}
+		resp, err := r.client.GetChange(reqParams)
+		if err != nil {
+			return false, fmt.Errorf("Failed to query Route 53 change status: %v", err)
+		}
+		if *resp.ChangeInfo.Status == route53.ChangeStatusInsync {
+			return true, nil
+		}
+		return false, nil
+	})
+}
+
+func getHostedZoneID(fqdn string, client *route53.Route53) (string, error) {
+	authZone, err := acme.FindZoneByFqdn(fqdn, acme.RecursiveNameservers)
+	if err != nil {
+		return "", err
+	}
+
+	// .DNSName should not have a trailing dot
+	reqParams := &route53.ListHostedZonesByNameInput{
+		DNSName: aws.String(acme.UnFqdn(authZone)),
+	}
+	resp, err := client.ListHostedZonesByName(reqParams)
+	if err != nil {
+		return "", err
+	}
+
+	var hostedZoneID string
+	for _, hostedZone := range resp.HostedZones {
+		// .Name has a trailing dot
+		if !*hostedZone.Config.PrivateZone && *hostedZone.Name == authZone {
+			hostedZoneID = *hostedZone.Id
+			break
+		}
+	}
+
+	if len(hostedZoneID) == 0 {
+		return "", fmt.Errorf("Zone %s not found in Route 53 for domain %s", authZone, fqdn)
+	}
+
+	if strings.HasPrefix(hostedZoneID, "/hostedzone/") {
+		hostedZoneID = strings.TrimPrefix(hostedZoneID, "/hostedzone/")
+	}
+
+	return hostedZoneID, nil
+}
+
+func newTXTRecordSet(fqdn, value string, ttl int) *route53.ResourceRecordSet {
+	return &route53.ResourceRecordSet{
+		Name: aws.String(fqdn),
+		Type: aws.String("TXT"),
+		TTL:  aws.Int64(int64(ttl)),
+		ResourceRecords: []*route53.ResourceRecord{
+			{Value: aws.String(value)},
+		},
+	}
+}

vendor/github.com/xenolf/lego/providers/dns/vultr/vultr.go

@@ -0,0 +1,127 @@
+// Package vultr implements a DNS provider for solving the DNS-01 challenge using
+// the vultr DNS.
+// See https://www.vultr.com/api/#dns
+package vultr
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	vultr "github.com/JamesClonk/vultr/lib"
+	"github.com/xenolf/lego/acme"
+)
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface.
+type DNSProvider struct {
+	client *vultr.Client
+}
+
+// NewDNSProvider returns a DNSProvider instance with a configured Vultr client.
+// Authentication uses the VULTR_API_KEY environment variable.
+func NewDNSProvider() (*DNSProvider, error) {
+	apiKey := os.Getenv("VULTR_API_KEY")
+	return NewDNSProviderCredentials(apiKey)
+}
+
+// NewDNSProviderCredentials uses the supplied credentials to return a DNSProvider
+// instance configured for Vultr.
+func NewDNSProviderCredentials(apiKey string) (*DNSProvider, error) {
+	if apiKey == "" {
+		return nil, fmt.Errorf("Vultr credentials missing")
+	}
+
+	c := &DNSProvider{
+		client: vultr.NewClient(apiKey, nil),
+	}
+
+	return c, nil
+}
+
+// Present creates a TXT record to fulfil the DNS-01 challenge.
+func (c *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, ttl := acme.DNS01Record(domain, keyAuth)
+
+	zoneDomain, err := c.getHostedZone(domain)
+	if err != nil {
+		return err
+	}
+
+	name := c.extractRecordName(fqdn, zoneDomain)
+
+	err = c.client.CreateDNSRecord(zoneDomain, name, "TXT", `"`+value+`"`, 0, ttl)
+	if err != nil {
+		return fmt.Errorf("Vultr API call failed: %v", err)
+	}
+
+	return nil
+}
+
+// CleanUp removes the TXT record matching the specified parameters.
+func (c *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	zoneDomain, records, err := c.findTxtRecords(domain, fqdn)
+	if err != nil {
+		return err
+	}
+
+	for _, rec := range records {
+		err := c.client.DeleteDNSRecord(zoneDomain, rec.RecordID)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (c *DNSProvider) getHostedZone(domain string) (string, error) {
+	domains, err := c.client.GetDNSDomains()
+	if err != nil {
+		return "", fmt.Errorf("Vultr API call failed: %v", err)
+	}
+
+	var hostedDomain vultr.DNSDomain
+	for _, d := range domains {
+		if strings.HasSuffix(domain, d.Domain) {
+			if len(d.Domain) > len(hostedDomain.Domain) {
+				hostedDomain = d
+			}
+		}
+	}
+	if hostedDomain.Domain == "" {
+		return "", fmt.Errorf("No matching Vultr domain found for domain %s", domain)
+	}
+
+	return hostedDomain.Domain, nil
+}
+
+func (c *DNSProvider) findTxtRecords(domain, fqdn string) (string, []vultr.DNSRecord, error) {
+	zoneDomain, err := c.getHostedZone(domain)
+	if err != nil {
+		return "", nil, err
+	}
+
+	var records []vultr.DNSRecord
+	result, err := c.client.GetDNSRecords(zoneDomain)
+	if err != nil {
+		return "", records, fmt.Errorf("Vultr API call has failed: %v", err)
+	}
+
+	recordName := c.extractRecordName(fqdn, zoneDomain)
+	for _, record := range result {
+		if record.Type == "TXT" && record.Name == recordName {
+			records = append(records, record)
+		}
+	}
+
+	return zoneDomain, records, nil
+}
+
+func (c *DNSProvider) extractRecordName(fqdn, domain string) string {
+	name := acme.UnFqdn(fqdn)
+	if idx := strings.Index(name, "."+domain); idx != -1 {
+		return name[:idx]
+	}
+	return name
+}