Replace godep with vndr

Vndr has a simpler configuration and allows pointing to forked
packages. Additionally other docker projects are now using
vndr making vendoring in distribution more consistent.

Updates letsencrypt to use fork.
No longer uses sub-vendored packages.

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)

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 +1,702 @@
+// 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
+	issuerCert []byte
+	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. It will
+// generate private keys for certificates of size keyBits.
+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 that will make the solution available
+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.
+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.
+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
+	hdr, err := postJSON(c.jws, c.directory.NewRegURL, regMsg, &serverReg)
+	if err != nil {
+		return nil, err
+	}
+
+	reg := &RegistrationResource{Body: serverReg}
+
+	links := parseLinks(hdr["Link"])
+	reg.URI = hdr.Get("Location")
+	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
+}
+
+// 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) (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)
+	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 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()))
+
+	// The first step of renewal is to check if we get a renewed cert
+	// directly from the cert URL.
+	resp, err := httpGet(cert.CertURL)
+	if err != nil {
+		return CertificateResource{}, err
+	}
+	defer resp.Body.Close()
+	serverCertBytes, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return CertificateResource{}, err
+	}
+
+	serverCert, err := x509.ParseCertificate(serverCertBytes)
+	if err != nil {
+		return CertificateResource{}, err
+	}
+
+	// If the server responds with a different certificate we are effectively renewed.
+	// TODO: Further test if we can actually use the new certificate (Our private key works)
+	if !x509Cert.Equal(serverCert) {
+		logf("[INFO][%s] acme: Server responded with renewed certificate", cert.Domain)
+		issuedCert := pemEncode(derCertificateBytes(serverCertBytes))
+		// If bundle is true, we want to return a certificate bundle.
+		// To do this, we need the issuer certificate.
+		if bundle {
+			// 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("[ERROR][%s] acme: Could not bundle issuer certificate: %v", cert.Domain, err)
+			} else {
+				// Success - append the issuer cert to the issued cert.
+				issuerCert = pemEncode(derCertificateBytes(issuerCert))
+				issuedCert = append(issuedCert, issuerCert...)
+			}
+		}
+
+		cert.Certificate = issuedCert
+		return cert, nil
+	}
+
+	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)
+	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 {
+		// 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) (CertificateResource, error) {
+	if len(authz) == 0 {
+		return CertificateResource{}, errors.New("Passed no authorizations to requestCertificate!")
+	}
+
+	commonName := authz[0]
+	var err error
+	if privKey == nil {
+		privKey, err = generatePrivateKey(c.keyType)
+		if err != nil {
+			return CertificateResource{}, err
+		}
+	}
+
+	var san []string
+	var authURLs []string
+	for _, auth := range authz[1:] {
+		san = append(san, auth.Domain)
+		authURLs = append(authURLs, auth.AuthURL)
+	}
+
+	// TODO: should the CSR be customizable?
+	csr, err := generateCsr(privKey, commonName.Domain, san)
+	if err != nil {
+		return CertificateResource{}, err
+	}
+
+	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
+	}
+
+	privateKeyPem := pemEncode(privKey)
+	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))
+				// If bundle is true, we want to return a certificate bundle.
+				// To do this, we need the issuer certificate.
+				if bundle {
+					// 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 {
+						// Success - append the issuer cert to the issued cert.
+						issuerCert = pemEncode(derCertificateBytes(issuerCert))
+						issuedCert = append(issuedCert, issuerCert...)
+					}
+				}
+
+				cerRes.Certificate = issuedCert
+				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 and caches it for
+// subsequent requests.
+func (c *Client) getIssuerCertificate(url string) ([]byte, error) {
+	logf("[INFO] acme: Requesting issuer cert from %s", url)
+	if c.issuerCert != nil {
+		return c.issuerCert, nil
+	}
+
+	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
+	}
+
+	c.issuerCert = issuerBytes
+	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 +1,323 @@
+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"
+
+	"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
+)
+
+// 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
+	}
+
+	if ocspRes.Certificate == nil {
+		err = ocspRes.CheckSignatureFrom(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) ([]byte, error) {
+	template := x509.CertificateRequest{
+		Subject: pkix.Name{
+			CommonName: domain,
+		},
+	}
+
+	if len(san) > 0 {
+		template.DNSNames = san
+	}
+
+	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 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)
+}
+
+// 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 +1,279 @@
+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 preCheckDNSFunc = checkDNSPropagation
+	fqdnToZone                  = map[string]string{}
+)
+
+var RecursiveNameservers = []string{
+	"google-public-dns-a.google.com:53",
+	"google-public-dns-b.google.com:53",
+}
+
+// DNSTimeout is used to override the default DNS timeout of 10 seconds.
+var DNSTimeout = 10 * time.Second
+
+// 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...", domain)
+
+	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, 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 of the given fqdn
+func FindZoneByFqdn(fqdn string, nameservers []string) (string, error) {
+	// Do we have it cached?
+	if zone, ok := fqdnToZone[fqdn]; ok {
+		return zone, nil
+	}
+
+	// Query the authoritative nameserver for a hopefully non-existing SOA record,
+	// in the authority section of the reply it will have the SOA of the
+	// containing zone. rfc2308 has this to say on the subject:
+	//   Name servers authoritative for a zone MUST include the SOA record of
+	//   the zone in the authority section of the response when reporting an
+	//   NXDOMAIN or indicating that no data (NODATA) of the requested type exists
+	in, err := dnsQuery(fqdn, dns.TypeSOA, nameservers, true)
+	if err != nil {
+		return "", err
+	}
+	if in.Rcode != dns.RcodeNameError {
+		if in.Rcode != dns.RcodeSuccess {
+			return "", fmt.Errorf("The NS returned %s for %s", dns.RcodeToString[in.Rcode], fqdn)
+		}
+		// We have a success, so one of the answers has to be a SOA RR
+		for _, ans := range in.Answer {
+			if soa, ok := ans.(*dns.SOA); ok {
+				return checkIfTLD(fqdn, soa)
+			}
+		}
+		// Or it is NODATA, fall through to NXDOMAIN
+	}
+	// Search the authority section for our precious SOA RR
+	for _, ns := range in.Ns {
+		if soa, ok := ns.(*dns.SOA); ok {
+			return checkIfTLD(fqdn, soa)
+		}
+	}
+	return "", fmt.Errorf("The NS did not return the expected SOA record in the authority section")
+}
+
+func checkIfTLD(fqdn string, soa *dns.SOA) (string, error) {
+	zone := soa.Hdr.Name
+	// If we ended up on one of the TLDs, it means the domain did not exist.
+	publicsuffix, _ := publicsuffix.PublicSuffix(UnFqdn(zone))
+	if publicsuffix == UnFqdn(zone) {
+		return "", fmt.Errorf("Could not determine zone authoritatively")
+	}
+	fqdnToZone[fqdn] = zone
+	return zone, nil
+}
+
+// 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 +1,120 @@
+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
+
+// HTTPTimeout is used to override the default HTTP timeout of 10 seconds.
+var HTTPTimeout = 10 * time.Second
+
+// defaultClient is an HTTP client with a reasonable timeout value.
+var defaultClient = http.Client{Timeout: HTTPTimeout}
+
+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 = defaultClient.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 defaultClient.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 defaultClient.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("[INFO] Received request for domain %s with method %s", 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 +1,109 @@
+package acme
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rsa"
+	"fmt"
+	"net/http"
+
+	"gopkg.in/square/go-jose.v1"
+)
+
+type jws struct {
+	directoryURL string
+	privKey      crypto.PrivateKey
+	nonces       []string
+}
+
+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.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) {
+	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 +1,116 @@
+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 recoveryKeyMessage struct {
+	Length int             `json:"length,omitempty"`
+	Client jose.JsonWebKey `json:"client,omitempty"`
+	Server jose.JsonWebKey `json:"client,omitempty"`
+}
+
+type registrationMessage struct {
+	Resource string   `json:"resource"`
+	Contact  []string `json:"contact"`
+	Delete   bool     `json:"delete,omitempty"`
+	//	RecoveryKey recoveryKeyMessage `json:"recoveryKey,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"`
+	//	RecoveryKey    recoveryKeyMessage `json:"recoveryKey,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 and Certificate are both 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:"-"`
+}

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)
+	}
+}