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