diff options
Diffstat (limited to 'vendor/golang.org/x/crypto/acme/acme.go')
| -rw-r--r-- | vendor/golang.org/x/crypto/acme/acme.go | 922 |
1 files changed, 0 insertions, 922 deletions
diff --git a/vendor/golang.org/x/crypto/acme/acme.go b/vendor/golang.org/x/crypto/acme/acme.go deleted file mode 100644 index 7df6476..0000000 --- a/vendor/golang.org/x/crypto/acme/acme.go +++ /dev/null @@ -1,922 +0,0 @@ -// Copyright 2015 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// Package acme provides an implementation of the -// Automatic Certificate Management Environment (ACME) spec. -// See https://tools.ietf.org/html/draft-ietf-acme-acme-02 for details. -// -// Most common scenarios will want to use autocert subdirectory instead, -// which provides automatic access to certificates from Let's Encrypt -// and any other ACME-based CA. -// -// This package is a work in progress and makes no API stability promises. -package acme - -import ( - "context" - "crypto" - "crypto/ecdsa" - "crypto/elliptic" - "crypto/rand" - "crypto/sha256" - "crypto/tls" - "crypto/x509" - "crypto/x509/pkix" - "encoding/asn1" - "encoding/base64" - "encoding/hex" - "encoding/json" - "encoding/pem" - "errors" - "fmt" - "io" - "io/ioutil" - "math/big" - "net/http" - "strings" - "sync" - "time" -) - -const ( - // LetsEncryptURL is the Directory endpoint of Let's Encrypt CA. - LetsEncryptURL = "https://acme-v01.api.letsencrypt.org/directory" - - // ALPNProto is the ALPN protocol name used by a CA server when validating - // tls-alpn-01 challenges. - // - // Package users must ensure their servers can negotiate the ACME ALPN in - // order for tls-alpn-01 challenge verifications to succeed. - // See the crypto/tls package's Config.NextProtos field. - ALPNProto = "acme-tls/1" -) - -// idPeACMEIdentifierV1 is the OID for the ACME extension for the TLS-ALPN challenge. -var idPeACMEIdentifierV1 = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 1, 30, 1} - -const ( - maxChainLen = 5 // max depth and breadth of a certificate chain - maxCertSize = 1 << 20 // max size of a certificate, in bytes - - // Max number of collected nonces kept in memory. - // Expect usual peak of 1 or 2. - maxNonces = 100 -) - -// Client is an ACME client. -// The only required field is Key. An example of creating a client with a new key -// is as follows: -// -// key, err := rsa.GenerateKey(rand.Reader, 2048) -// if err != nil { -// log.Fatal(err) -// } -// client := &Client{Key: key} -// -type Client struct { - // Key is the account key used to register with a CA and sign requests. - // Key.Public() must return a *rsa.PublicKey or *ecdsa.PublicKey. - Key crypto.Signer - - // HTTPClient optionally specifies an HTTP client to use - // instead of http.DefaultClient. - HTTPClient *http.Client - - // DirectoryURL points to the CA directory endpoint. - // If empty, LetsEncryptURL is used. - // Mutating this value after a successful call of Client's Discover method - // will have no effect. - DirectoryURL string - - // RetryBackoff computes the duration after which the nth retry of a failed request - // should occur. The value of n for the first call on failure is 1. - // The values of r and resp are the request and response of the last failed attempt. - // If the returned value is negative or zero, no more retries are done and an error - // is returned to the caller of the original method. - // - // Requests which result in a 4xx client error are not retried, - // except for 400 Bad Request due to "bad nonce" errors and 429 Too Many Requests. - // - // If RetryBackoff is nil, a truncated exponential backoff algorithm - // with the ceiling of 10 seconds is used, where each subsequent retry n - // is done after either ("Retry-After" + jitter) or (2^n seconds + jitter), - // preferring the former if "Retry-After" header is found in the resp. - // The jitter is a random value up to 1 second. - RetryBackoff func(n int, r *http.Request, resp *http.Response) time.Duration - - dirMu sync.Mutex // guards writes to dir - dir *Directory // cached result of Client's Discover method - - noncesMu sync.Mutex - nonces map[string]struct{} // nonces collected from previous responses -} - -// Discover performs ACME server discovery using c.DirectoryURL. -// -// It caches successful result. So, subsequent calls will not result in -// a network round-trip. This also means mutating c.DirectoryURL after successful call -// of this method will have no effect. -func (c *Client) Discover(ctx context.Context) (Directory, error) { - c.dirMu.Lock() - defer c.dirMu.Unlock() - if c.dir != nil { - return *c.dir, nil - } - - dirURL := c.DirectoryURL - if dirURL == "" { - dirURL = LetsEncryptURL - } - res, err := c.get(ctx, dirURL, wantStatus(http.StatusOK)) - if err != nil { - return Directory{}, err - } - defer res.Body.Close() - c.addNonce(res.Header) - - var v struct { - Reg string `json:"new-reg"` - Authz string `json:"new-authz"` - Cert string `json:"new-cert"` - Revoke string `json:"revoke-cert"` - Meta struct { - Terms string `json:"terms-of-service"` - Website string `json:"website"` - CAA []string `json:"caa-identities"` - } - } - if err := json.NewDecoder(res.Body).Decode(&v); err != nil { - return Directory{}, err - } - c.dir = &Directory{ - RegURL: v.Reg, - AuthzURL: v.Authz, - CertURL: v.Cert, - RevokeURL: v.Revoke, - Terms: v.Meta.Terms, - Website: v.Meta.Website, - CAA: v.Meta.CAA, - } - return *c.dir, nil -} - -// CreateCert requests a new certificate using the Certificate Signing Request csr encoded in DER format. -// The exp argument indicates the desired certificate validity duration. CA may issue a certificate -// with a different duration. -// If the bundle argument is true, the returned value will also contain the CA (issuer) certificate chain. -// -// In the case where CA server does not provide the issued certificate in the response, -// CreateCert will poll certURL using c.FetchCert, which will result in additional round-trips. -// In such a scenario, the caller can cancel the polling with ctx. -// -// CreateCert returns an error if the CA's response or chain was unreasonably large. -// Callers are encouraged to parse the returned value to ensure the certificate is valid and has the expected features. -func (c *Client) CreateCert(ctx context.Context, csr []byte, exp time.Duration, bundle bool) (der [][]byte, certURL string, err error) { - if _, err := c.Discover(ctx); err != nil { - return nil, "", err - } - - req := struct { - Resource string `json:"resource"` - CSR string `json:"csr"` - NotBefore string `json:"notBefore,omitempty"` - NotAfter string `json:"notAfter,omitempty"` - }{ - Resource: "new-cert", - CSR: base64.RawURLEncoding.EncodeToString(csr), - } - now := timeNow() - req.NotBefore = now.Format(time.RFC3339) - if exp > 0 { - req.NotAfter = now.Add(exp).Format(time.RFC3339) - } - - res, err := c.post(ctx, c.Key, c.dir.CertURL, req, wantStatus(http.StatusCreated)) - if err != nil { - return nil, "", err - } - defer res.Body.Close() - - curl := res.Header.Get("Location") // cert permanent URL - if res.ContentLength == 0 { - // no cert in the body; poll until we get it - cert, err := c.FetchCert(ctx, curl, bundle) - return cert, curl, err - } - // slurp issued cert and CA chain, if requested - cert, err := c.responseCert(ctx, res, bundle) - return cert, curl, err -} - -// FetchCert retrieves already issued certificate from the given url, in DER format. -// It retries the request until the certificate is successfully retrieved, -// context is cancelled by the caller or an error response is received. -// -// The returned value will also contain the CA (issuer) certificate if the bundle argument is true. -// -// FetchCert returns an error if the CA's response or chain was unreasonably large. -// Callers are encouraged to parse the returned value to ensure the certificate is valid -// and has expected features. -func (c *Client) FetchCert(ctx context.Context, url string, bundle bool) ([][]byte, error) { - res, err := c.get(ctx, url, wantStatus(http.StatusOK)) - if err != nil { - return nil, err - } - return c.responseCert(ctx, res, bundle) -} - -// RevokeCert revokes a previously issued certificate cert, provided in DER format. -// -// The key argument, used to sign the request, must be authorized -// to revoke the certificate. It's up to the CA to decide which keys are authorized. -// For instance, the key pair of the certificate may be authorized. -// If the key is nil, c.Key is used instead. -func (c *Client) RevokeCert(ctx context.Context, key crypto.Signer, cert []byte, reason CRLReasonCode) error { - if _, err := c.Discover(ctx); err != nil { - return err - } - - body := &struct { - Resource string `json:"resource"` - Cert string `json:"certificate"` - Reason int `json:"reason"` - }{ - Resource: "revoke-cert", - Cert: base64.RawURLEncoding.EncodeToString(cert), - Reason: int(reason), - } - if key == nil { - key = c.Key - } - res, err := c.post(ctx, key, c.dir.RevokeURL, body, wantStatus(http.StatusOK)) - if err != nil { - return err - } - defer res.Body.Close() - return nil -} - -// AcceptTOS always returns true to indicate the acceptance of a CA's Terms of Service -// during account registration. See Register method of Client for more details. -func AcceptTOS(tosURL string) bool { return true } - -// Register creates a new account registration by following the "new-reg" flow. -// It returns the registered account. The account is not modified. -// -// The registration may require the caller to agree to the CA's Terms of Service (TOS). -// If so, and the account has not indicated the acceptance of the terms (see Account for details), -// Register calls prompt with a TOS URL provided by the CA. Prompt should report -// whether the caller agrees to the terms. To always accept the terms, the caller can use AcceptTOS. -func (c *Client) Register(ctx context.Context, a *Account, prompt func(tosURL string) bool) (*Account, error) { - if _, err := c.Discover(ctx); err != nil { - return nil, err - } - - var err error - if a, err = c.doReg(ctx, c.dir.RegURL, "new-reg", a); err != nil { - return nil, err - } - var accept bool - if a.CurrentTerms != "" && a.CurrentTerms != a.AgreedTerms { - accept = prompt(a.CurrentTerms) - } - if accept { - a.AgreedTerms = a.CurrentTerms - a, err = c.UpdateReg(ctx, a) - } - return a, err -} - -// GetReg retrieves an existing registration. -// The url argument is an Account URI. -func (c *Client) GetReg(ctx context.Context, url string) (*Account, error) { - a, err := c.doReg(ctx, url, "reg", nil) - if err != nil { - return nil, err - } - a.URI = url - return a, nil -} - -// UpdateReg updates an existing registration. -// It returns an updated account copy. The provided account is not modified. -func (c *Client) UpdateReg(ctx context.Context, a *Account) (*Account, error) { - uri := a.URI - a, err := c.doReg(ctx, uri, "reg", a) - if err != nil { - return nil, err - } - a.URI = uri - return a, nil -} - -// Authorize performs the initial step in an authorization flow. -// The caller will then need to choose from and perform a set of returned -// challenges using c.Accept in order to successfully complete authorization. -// -// If an authorization has been previously granted, the CA may return -// a valid authorization (Authorization.Status is StatusValid). If so, the caller -// need not fulfill any challenge and can proceed to requesting a certificate. -func (c *Client) Authorize(ctx context.Context, domain string) (*Authorization, error) { - if _, err := c.Discover(ctx); err != nil { - return nil, err - } - - type authzID struct { - Type string `json:"type"` - Value string `json:"value"` - } - req := struct { - Resource string `json:"resource"` - Identifier authzID `json:"identifier"` - }{ - Resource: "new-authz", - Identifier: authzID{Type: "dns", Value: domain}, - } - res, err := c.post(ctx, c.Key, c.dir.AuthzURL, req, wantStatus(http.StatusCreated)) - if err != nil { - return nil, err - } - defer res.Body.Close() - - var v wireAuthz - if err := json.NewDecoder(res.Body).Decode(&v); err != nil { - return nil, fmt.Errorf("acme: invalid response: %v", err) - } - if v.Status != StatusPending && v.Status != StatusValid { - return nil, fmt.Errorf("acme: unexpected status: %s", v.Status) - } - return v.authorization(res.Header.Get("Location")), nil -} - -// GetAuthorization retrieves an authorization identified by the given URL. -// -// If a caller needs to poll an authorization until its status is final, -// see the WaitAuthorization method. -func (c *Client) GetAuthorization(ctx context.Context, url string) (*Authorization, error) { - res, err := c.get(ctx, url, wantStatus(http.StatusOK, http.StatusAccepted)) - if err != nil { - return nil, err - } - defer res.Body.Close() - var v wireAuthz - if err := json.NewDecoder(res.Body).Decode(&v); err != nil { - return nil, fmt.Errorf("acme: invalid response: %v", err) - } - return v.authorization(url), nil -} - -// RevokeAuthorization relinquishes an existing authorization identified -// by the given URL. -// The url argument is an Authorization.URI value. -// -// If successful, the caller will be required to obtain a new authorization -// using the Authorize method before being able to request a new certificate -// for the domain associated with the authorization. -// -// It does not revoke existing certificates. -func (c *Client) RevokeAuthorization(ctx context.Context, url string) error { - req := struct { - Resource string `json:"resource"` - Status string `json:"status"` - Delete bool `json:"delete"` - }{ - Resource: "authz", - Status: "deactivated", - Delete: true, - } - res, err := c.post(ctx, c.Key, url, req, wantStatus(http.StatusOK)) - if err != nil { - return err - } - defer res.Body.Close() - return nil -} - -// WaitAuthorization polls an authorization at the given URL -// until it is in one of the final states, StatusValid or StatusInvalid, -// the ACME CA responded with a 4xx error code, or the context is done. -// -// It returns a non-nil Authorization only if its Status is StatusValid. -// In all other cases WaitAuthorization returns an error. -// If the Status is StatusInvalid, the returned error is of type *AuthorizationError. -func (c *Client) WaitAuthorization(ctx context.Context, url string) (*Authorization, error) { - for { - res, err := c.get(ctx, url, wantStatus(http.StatusOK, http.StatusAccepted)) - if err != nil { - return nil, err - } - - var raw wireAuthz - err = json.NewDecoder(res.Body).Decode(&raw) - res.Body.Close() - switch { - case err != nil: - // Skip and retry. - case raw.Status == StatusValid: - return raw.authorization(url), nil - case raw.Status == StatusInvalid: - return nil, raw.error(url) - } - - // Exponential backoff is implemented in c.get above. - // This is just to prevent continuously hitting the CA - // while waiting for a final authorization status. - d := retryAfter(res.Header.Get("Retry-After")) - if d == 0 { - // Given that the fastest challenges TLS-SNI and HTTP-01 - // require a CA to make at least 1 network round trip - // and most likely persist a challenge state, - // this default delay seems reasonable. - d = time.Second - } - t := time.NewTimer(d) - select { - case <-ctx.Done(): - t.Stop() - return nil, ctx.Err() - case <-t.C: - // Retry. - } - } -} - -// GetChallenge retrieves the current status of an challenge. -// -// A client typically polls a challenge status using this method. -func (c *Client) GetChallenge(ctx context.Context, url string) (*Challenge, error) { - res, err := c.get(ctx, url, wantStatus(http.StatusOK, http.StatusAccepted)) - if err != nil { - return nil, err - } - defer res.Body.Close() - v := wireChallenge{URI: url} - if err := json.NewDecoder(res.Body).Decode(&v); err != nil { - return nil, fmt.Errorf("acme: invalid response: %v", err) - } - return v.challenge(), nil -} - -// Accept informs the server that the client accepts one of its challenges -// previously obtained with c.Authorize. -// -// The server will then perform the validation asynchronously. -func (c *Client) Accept(ctx context.Context, chal *Challenge) (*Challenge, error) { - auth, err := keyAuth(c.Key.Public(), chal.Token) - if err != nil { - return nil, err - } - - req := struct { - Resource string `json:"resource"` - Type string `json:"type"` - Auth string `json:"keyAuthorization"` - }{ - Resource: "challenge", - Type: chal.Type, - Auth: auth, - } - res, err := c.post(ctx, c.Key, chal.URI, req, wantStatus( - http.StatusOK, // according to the spec - http.StatusAccepted, // Let's Encrypt: see https://goo.gl/WsJ7VT (acme-divergences.md) - )) - if err != nil { - return nil, err - } - defer res.Body.Close() - - var v wireChallenge - if err := json.NewDecoder(res.Body).Decode(&v); err != nil { - return nil, fmt.Errorf("acme: invalid response: %v", err) - } - return v.challenge(), nil -} - -// DNS01ChallengeRecord returns a DNS record value for a dns-01 challenge response. -// A TXT record containing the returned value must be provisioned under -// "_acme-challenge" name of the domain being validated. -// -// The token argument is a Challenge.Token value. -func (c *Client) DNS01ChallengeRecord(token string) (string, error) { - ka, err := keyAuth(c.Key.Public(), token) - if err != nil { - return "", err - } - b := sha256.Sum256([]byte(ka)) - return base64.RawURLEncoding.EncodeToString(b[:]), nil -} - -// HTTP01ChallengeResponse returns the response for an http-01 challenge. -// Servers should respond with the value to HTTP requests at the URL path -// provided by HTTP01ChallengePath to validate the challenge and prove control -// over a domain name. -// -// The token argument is a Challenge.Token value. -func (c *Client) HTTP01ChallengeResponse(token string) (string, error) { - return keyAuth(c.Key.Public(), token) -} - -// HTTP01ChallengePath returns the URL path at which the response for an http-01 challenge -// should be provided by the servers. -// The response value can be obtained with HTTP01ChallengeResponse. -// -// The token argument is a Challenge.Token value. -func (c *Client) HTTP01ChallengePath(token string) string { - return "/.well-known/acme-challenge/" + token -} - -// TLSSNI01ChallengeCert creates a certificate for TLS-SNI-01 challenge response. -// Servers can present the certificate to validate the challenge and prove control -// over a domain name. -// -// The implementation is incomplete in that the returned value is a single certificate, -// computed only for Z0 of the key authorization. ACME CAs are expected to update -// their implementations to use the newer version, TLS-SNI-02. -// For more details on TLS-SNI-01 see https://tools.ietf.org/html/draft-ietf-acme-acme-01#section-7.3. -// -// The token argument is a Challenge.Token value. -// If a WithKey option is provided, its private part signs the returned cert, -// and the public part is used to specify the signee. -// If no WithKey option is provided, a new ECDSA key is generated using P-256 curve. -// -// The returned certificate is valid for the next 24 hours and must be presented only when -// the server name of the TLS ClientHello matches exactly the returned name value. -func (c *Client) TLSSNI01ChallengeCert(token string, opt ...CertOption) (cert tls.Certificate, name string, err error) { - ka, err := keyAuth(c.Key.Public(), token) - if err != nil { - return tls.Certificate{}, "", err - } - b := sha256.Sum256([]byte(ka)) - h := hex.EncodeToString(b[:]) - name = fmt.Sprintf("%s.%s.acme.invalid", h[:32], h[32:]) - cert, err = tlsChallengeCert([]string{name}, opt) - if err != nil { - return tls.Certificate{}, "", err - } - return cert, name, nil -} - -// TLSSNI02ChallengeCert creates a certificate for TLS-SNI-02 challenge response. -// Servers can present the certificate to validate the challenge and prove control -// over a domain name. For more details on TLS-SNI-02 see -// https://tools.ietf.org/html/draft-ietf-acme-acme-03#section-7.3. -// -// The token argument is a Challenge.Token value. -// If a WithKey option is provided, its private part signs the returned cert, -// and the public part is used to specify the signee. -// If no WithKey option is provided, a new ECDSA key is generated using P-256 curve. -// -// The returned certificate is valid for the next 24 hours and must be presented only when -// the server name in the TLS ClientHello matches exactly the returned name value. -func (c *Client) TLSSNI02ChallengeCert(token string, opt ...CertOption) (cert tls.Certificate, name string, err error) { - b := sha256.Sum256([]byte(token)) - h := hex.EncodeToString(b[:]) - sanA := fmt.Sprintf("%s.%s.token.acme.invalid", h[:32], h[32:]) - - ka, err := keyAuth(c.Key.Public(), token) - if err != nil { - return tls.Certificate{}, "", err - } - b = sha256.Sum256([]byte(ka)) - h = hex.EncodeToString(b[:]) - sanB := fmt.Sprintf("%s.%s.ka.acme.invalid", h[:32], h[32:]) - - cert, err = tlsChallengeCert([]string{sanA, sanB}, opt) - if err != nil { - return tls.Certificate{}, "", err - } - return cert, sanA, nil -} - -// TLSALPN01ChallengeCert creates a certificate for TLS-ALPN-01 challenge response. -// Servers can present the certificate to validate the challenge and prove control -// over a domain name. For more details on TLS-ALPN-01 see -// https://tools.ietf.org/html/draft-shoemaker-acme-tls-alpn-00#section-3 -// -// The token argument is a Challenge.Token value. -// If a WithKey option is provided, its private part signs the returned cert, -// and the public part is used to specify the signee. -// If no WithKey option is provided, a new ECDSA key is generated using P-256 curve. -// -// The returned certificate is valid for the next 24 hours and must be presented only when -// the server name in the TLS ClientHello matches the domain, and the special acme-tls/1 ALPN protocol -// has been specified. -func (c *Client) TLSALPN01ChallengeCert(token, domain string, opt ...CertOption) (cert tls.Certificate, err error) { - ka, err := keyAuth(c.Key.Public(), token) - if err != nil { - return tls.Certificate{}, err - } - shasum := sha256.Sum256([]byte(ka)) - extValue, err := asn1.Marshal(shasum[:]) - if err != nil { - return tls.Certificate{}, err - } - acmeExtension := pkix.Extension{ - Id: idPeACMEIdentifierV1, - Critical: true, - Value: extValue, - } - - tmpl := defaultTLSChallengeCertTemplate() - - var newOpt []CertOption - for _, o := range opt { - switch o := o.(type) { - case *certOptTemplate: - t := *(*x509.Certificate)(o) // shallow copy is ok - tmpl = &t - default: - newOpt = append(newOpt, o) - } - } - tmpl.ExtraExtensions = append(tmpl.ExtraExtensions, acmeExtension) - newOpt = append(newOpt, WithTemplate(tmpl)) - return tlsChallengeCert([]string{domain}, newOpt) -} - -// doReg sends all types of registration requests. -// The type of request is identified by typ argument, which is a "resource" -// in the ACME spec terms. -// -// A non-nil acct argument indicates whether the intention is to mutate data -// of the Account. Only Contact and Agreement of its fields are used -// in such cases. -func (c *Client) doReg(ctx context.Context, url string, typ string, acct *Account) (*Account, error) { - req := struct { - Resource string `json:"resource"` - Contact []string `json:"contact,omitempty"` - Agreement string `json:"agreement,omitempty"` - }{ - Resource: typ, - } - if acct != nil { - req.Contact = acct.Contact - req.Agreement = acct.AgreedTerms - } - res, err := c.post(ctx, c.Key, url, req, wantStatus( - http.StatusOK, // updates and deletes - http.StatusCreated, // new account creation - http.StatusAccepted, // Let's Encrypt divergent implementation - )) - if err != nil { - return nil, err - } - defer res.Body.Close() - - var v struct { - Contact []string - Agreement string - Authorizations string - Certificates string - } - if err := json.NewDecoder(res.Body).Decode(&v); err != nil { - return nil, fmt.Errorf("acme: invalid response: %v", err) - } - var tos string - if v := linkHeader(res.Header, "terms-of-service"); len(v) > 0 { - tos = v[0] - } - var authz string - if v := linkHeader(res.Header, "next"); len(v) > 0 { - authz = v[0] - } - return &Account{ - URI: res.Header.Get("Location"), - Contact: v.Contact, - AgreedTerms: v.Agreement, - CurrentTerms: tos, - Authz: authz, - Authorizations: v.Authorizations, - Certificates: v.Certificates, - }, nil -} - -// popNonce returns a nonce value previously stored with c.addNonce -// or fetches a fresh one from the given URL. -func (c *Client) popNonce(ctx context.Context, url string) (string, error) { - c.noncesMu.Lock() - defer c.noncesMu.Unlock() - if len(c.nonces) == 0 { - return c.fetchNonce(ctx, url) - } - var nonce string - for nonce = range c.nonces { - delete(c.nonces, nonce) - break - } - return nonce, nil -} - -// clearNonces clears any stored nonces -func (c *Client) clearNonces() { - c.noncesMu.Lock() - defer c.noncesMu.Unlock() - c.nonces = make(map[string]struct{}) -} - -// addNonce stores a nonce value found in h (if any) for future use. -func (c *Client) addNonce(h http.Header) { - v := nonceFromHeader(h) - if v == "" { - return - } - c.noncesMu.Lock() - defer c.noncesMu.Unlock() - if len(c.nonces) >= maxNonces { - return - } - if c.nonces == nil { - c.nonces = make(map[string]struct{}) - } - c.nonces[v] = struct{}{} -} - -func (c *Client) fetchNonce(ctx context.Context, url string) (string, error) { - r, err := http.NewRequest("HEAD", url, nil) - if err != nil { - return "", err - } - resp, err := c.doNoRetry(ctx, r) - if err != nil { - return "", err - } - defer resp.Body.Close() - nonce := nonceFromHeader(resp.Header) - if nonce == "" { - if resp.StatusCode > 299 { - return "", responseError(resp) - } - return "", errors.New("acme: nonce not found") - } - return nonce, nil -} - -func nonceFromHeader(h http.Header) string { - return h.Get("Replay-Nonce") -} - -func (c *Client) responseCert(ctx context.Context, res *http.Response, bundle bool) ([][]byte, error) { - b, err := ioutil.ReadAll(io.LimitReader(res.Body, maxCertSize+1)) - if err != nil { - return nil, fmt.Errorf("acme: response stream: %v", err) - } - if len(b) > maxCertSize { - return nil, errors.New("acme: certificate is too big") - } - cert := [][]byte{b} - if !bundle { - return cert, nil - } - - // Append CA chain cert(s). - // At least one is required according to the spec: - // https://tools.ietf.org/html/draft-ietf-acme-acme-03#section-6.3.1 - up := linkHeader(res.Header, "up") - if len(up) == 0 { - return nil, errors.New("acme: rel=up link not found") - } - if len(up) > maxChainLen { - return nil, errors.New("acme: rel=up link is too large") - } - for _, url := range up { - cc, err := c.chainCert(ctx, url, 0) - if err != nil { - return nil, err - } - cert = append(cert, cc...) - } - return cert, nil -} - -// chainCert fetches CA certificate chain recursively by following "up" links. -// Each recursive call increments the depth by 1, resulting in an error -// if the recursion level reaches maxChainLen. -// -// First chainCert call starts with depth of 0. -func (c *Client) chainCert(ctx context.Context, url string, depth int) ([][]byte, error) { - if depth >= maxChainLen { - return nil, errors.New("acme: certificate chain is too deep") - } - - res, err := c.get(ctx, url, wantStatus(http.StatusOK)) - if err != nil { - return nil, err - } - defer res.Body.Close() - b, err := ioutil.ReadAll(io.LimitReader(res.Body, maxCertSize+1)) - if err != nil { - return nil, err - } - if len(b) > maxCertSize { - return nil, errors.New("acme: certificate is too big") - } - chain := [][]byte{b} - - uplink := linkHeader(res.Header, "up") - if len(uplink) > maxChainLen { - return nil, errors.New("acme: certificate chain is too large") - } - for _, up := range uplink { - cc, err := c.chainCert(ctx, up, depth+1) - if err != nil { - return nil, err - } - chain = append(chain, cc...) - } - - return chain, nil -} - -// linkHeader returns URI-Reference values of all Link headers -// with relation-type rel. -// See https://tools.ietf.org/html/rfc5988#section-5 for details. -func linkHeader(h http.Header, rel string) []string { - var links []string - for _, v := range h["Link"] { - parts := strings.Split(v, ";") - for _, p := range parts { - p = strings.TrimSpace(p) - if !strings.HasPrefix(p, "rel=") { - continue - } - if v := strings.Trim(p[4:], `"`); v == rel { - links = append(links, strings.Trim(parts[0], "<>")) - } - } - } - return links -} - -// keyAuth generates a key authorization string for a given token. -func keyAuth(pub crypto.PublicKey, token string) (string, error) { - th, err := JWKThumbprint(pub) - if err != nil { - return "", err - } - return fmt.Sprintf("%s.%s", token, th), nil -} - -// defaultTLSChallengeCertTemplate is a template used to create challenge certs for TLS challenges. -func defaultTLSChallengeCertTemplate() *x509.Certificate { - return &x509.Certificate{ - SerialNumber: big.NewInt(1), - NotBefore: time.Now(), - NotAfter: time.Now().Add(24 * time.Hour), - BasicConstraintsValid: true, - KeyUsage: x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature, - ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth}, - } -} - -// tlsChallengeCert creates a temporary certificate for TLS-SNI challenges -// with the given SANs and auto-generated public/private key pair. -// The Subject Common Name is set to the first SAN to aid debugging. -// To create a cert with a custom key pair, specify WithKey option. -func tlsChallengeCert(san []string, opt []CertOption) (tls.Certificate, error) { - var key crypto.Signer - tmpl := defaultTLSChallengeCertTemplate() - for _, o := range opt { - switch o := o.(type) { - case *certOptKey: - if key != nil { - return tls.Certificate{}, errors.New("acme: duplicate key option") - } - key = o.key - case *certOptTemplate: - t := *(*x509.Certificate)(o) // shallow copy is ok - tmpl = &t - default: - // package's fault, if we let this happen: - panic(fmt.Sprintf("unsupported option type %T", o)) - } - } - if key == nil { - var err error - if key, err = ecdsa.GenerateKey(elliptic.P256(), rand.Reader); err != nil { - return tls.Certificate{}, err - } - } - tmpl.DNSNames = san - if len(san) > 0 { - tmpl.Subject.CommonName = san[0] - } - - der, err := x509.CreateCertificate(rand.Reader, tmpl, tmpl, key.Public(), key) - if err != nil { - return tls.Certificate{}, err - } - return tls.Certificate{ - Certificate: [][]byte{der}, - PrivateKey: key, - }, nil -} - -// encodePEM returns b encoded as PEM with block of type typ. -func encodePEM(typ string, b []byte) []byte { - pb := &pem.Block{Type: typ, Bytes: b} - return pem.EncodeToMemory(pb) -} - -// timeNow is useful for testing for fixed current time. -var timeNow = time.Now |