mirror of
https://github.com/tailscale/tailscale.git
synced 2024-12-04 23:45:34 +00:00
347e3f3d9a
Update our fork of golang.org/x/crypto to pick up a fix for ACME ARI:
3fde5e568a
Fixes #12278
Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
696 lines
20 KiB
Go
696 lines
20 KiB
Go
// Copyright (c) Tailscale Inc & AUTHORS
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// SPDX-License-Identifier: BSD-3-Clause
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//go:build !js
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package ipnlocal
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import (
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"bytes"
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"context"
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"crypto"
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"crypto/ecdsa"
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"crypto/elliptic"
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"crypto/rand"
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"crypto/rsa"
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"crypto/tls"
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"crypto/x509"
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"crypto/x509/pkix"
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"encoding/json"
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"encoding/pem"
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"errors"
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"fmt"
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"io"
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"log"
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insecurerand "math/rand"
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"net"
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"os"
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"path/filepath"
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"runtime"
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"slices"
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"strings"
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"sync"
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"time"
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"github.com/tailscale/golang-x-crypto/acme"
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"tailscale.com/atomicfile"
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"tailscale.com/envknob"
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"tailscale.com/hostinfo"
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"tailscale.com/ipn"
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"tailscale.com/ipn/ipnstate"
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"tailscale.com/ipn/store"
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"tailscale.com/ipn/store/mem"
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"tailscale.com/types/logger"
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"tailscale.com/util/testenv"
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"tailscale.com/version"
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"tailscale.com/version/distro"
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)
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// Process-wide cache. (A new *Handler is created per connection,
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// effectively per request)
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var (
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// acmeMu guards all ACME operations, so concurrent requests
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// for certs don't slam ACME. The first will go through and
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// populate the on-disk cache and the rest should use that.
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acmeMu sync.Mutex
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renewMu sync.Mutex // lock order: acmeMu before renewMu
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renewCertAt = map[string]time.Time{}
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)
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// certDir returns (creating if needed) the directory in which cached
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// cert keypairs are stored.
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func (b *LocalBackend) certDir() (string, error) {
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d := b.TailscaleVarRoot()
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// As a workaround for Synology DSM6 not having a "var" directory, use the
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// app's "etc" directory (on a small partition) to hold certs at least.
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// See https://github.com/tailscale/tailscale/issues/4060#issuecomment-1186592251
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if d == "" && runtime.GOOS == "linux" && distro.Get() == distro.Synology && distro.DSMVersion() == 6 {
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d = "/var/packages/Tailscale/etc" // base; we append "certs" below
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}
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if d == "" {
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return "", errors.New("no TailscaleVarRoot")
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}
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full := filepath.Join(d, "certs")
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if err := os.MkdirAll(full, 0700); err != nil {
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return "", err
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}
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return full, nil
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}
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var acmeDebug = envknob.RegisterBool("TS_DEBUG_ACME")
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// GetCertPEM gets the TLSCertKeyPair for domain, either from cache or via the
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// ACME process. ACME process is used for new domain certs, existing expired
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// certs or existing certs that should get renewed due to upcoming expiry.
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//
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// If a cert is expired, it will be renewed synchronously otherwise it will be
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// renewed asynchronously.
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func (b *LocalBackend) GetCertPEM(ctx context.Context, domain string) (*TLSCertKeyPair, error) {
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if !validLookingCertDomain(domain) {
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return nil, errors.New("invalid domain")
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}
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logf := logger.WithPrefix(b.logf, fmt.Sprintf("cert(%q): ", domain))
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now := b.clock.Now()
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traceACME := func(v any) {
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if !acmeDebug() {
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return
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}
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j, _ := json.MarshalIndent(v, "", "\t")
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log.Printf("acme %T: %s", v, j)
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}
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cs, err := b.getCertStore()
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if err != nil {
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return nil, err
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}
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if pair, err := getCertPEMCached(cs, domain, now); err == nil {
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// If we got here, we have a valid unexpired cert.
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// Check whether we should start an async renewal.
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if shouldRenew, err := b.shouldStartDomainRenewal(cs, domain, now, pair); err != nil {
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logf("error checking for certificate renewal: %v", err)
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} else if shouldRenew {
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logf("starting async renewal")
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// Start renewal in the background.
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go b.getCertPEM(context.Background(), cs, logf, traceACME, domain, now)
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}
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return pair, nil
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}
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pair, err := b.getCertPEM(ctx, cs, logf, traceACME, domain, now)
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if err != nil {
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logf("getCertPEM: %v", err)
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return nil, err
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}
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return pair, nil
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}
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// shouldStartDomainRenewal reports whether the domain's cert should be renewed
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// based on the current time, the cert's expiry, and the ARI check.
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func (b *LocalBackend) shouldStartDomainRenewal(cs certStore, domain string, now time.Time, pair *TLSCertKeyPair) (bool, error) {
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renewMu.Lock()
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defer renewMu.Unlock()
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if renewAt, ok := renewCertAt[domain]; ok {
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return now.After(renewAt), nil
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}
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renewTime, err := b.domainRenewalTimeByARI(cs, pair)
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if err != nil {
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// Log any ARI failure and fall back to checking for renewal by expiry.
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b.logf("acme: ARI check failed: %v; falling back to expiry-based check", err)
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renewTime, err = b.domainRenewalTimeByExpiry(pair)
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if err != nil {
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return false, err
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}
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}
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renewCertAt[domain] = renewTime
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return now.After(renewTime), nil
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}
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func (b *LocalBackend) domainRenewed(domain string) {
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renewMu.Lock()
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defer renewMu.Unlock()
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delete(renewCertAt, domain)
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}
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func (b *LocalBackend) domainRenewalTimeByExpiry(pair *TLSCertKeyPair) (time.Time, error) {
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block, _ := pem.Decode(pair.CertPEM)
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if block == nil {
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return time.Time{}, fmt.Errorf("parsing certificate PEM")
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}
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cert, err := x509.ParseCertificate(block.Bytes)
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if err != nil {
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return time.Time{}, fmt.Errorf("parsing certificate: %w", err)
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}
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certLifetime := cert.NotAfter.Sub(cert.NotBefore)
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if certLifetime < 0 {
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return time.Time{}, fmt.Errorf("negative certificate lifetime %v", certLifetime)
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}
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// Per https://github.com/tailscale/tailscale/issues/8204, check
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// whether we're more than 2/3 of the way through the certificate's
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// lifetime, which is the officially-recommended best practice by Let's
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// Encrypt.
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renewalDuration := certLifetime * 2 / 3
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renewAt := cert.NotBefore.Add(renewalDuration)
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return renewAt, nil
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}
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func (b *LocalBackend) domainRenewalTimeByARI(cs certStore, pair *TLSCertKeyPair) (time.Time, error) {
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var blocks []*pem.Block
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rest := pair.CertPEM
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for len(rest) > 0 {
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var block *pem.Block
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block, rest = pem.Decode(rest)
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if block == nil {
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return time.Time{}, fmt.Errorf("parsing certificate PEM")
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}
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blocks = append(blocks, block)
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}
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if len(blocks) < 1 {
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return time.Time{}, fmt.Errorf("could not parse certificate chain from certStore, got %d PEM block(s)", len(blocks))
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}
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ac, err := acmeClient(cs)
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if err != nil {
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return time.Time{}, err
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}
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ctx, cancel := context.WithTimeout(b.ctx, 5*time.Second)
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defer cancel()
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ri, err := ac.FetchRenewalInfo(ctx, blocks[0].Bytes)
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if err != nil {
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return time.Time{}, fmt.Errorf("failed to fetch renewal info from ACME server: %w", err)
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}
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if acmeDebug() {
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b.logf("acme: ARI response: %+v", ri)
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}
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// Select a random time in the suggested window and renew if that time has
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// passed. Time is randomized per recommendation in
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// https://datatracker.ietf.org/doc/draft-ietf-acme-ari/
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start, end := ri.SuggestedWindow.Start, ri.SuggestedWindow.End
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renewTime := start.Add(time.Duration(insecurerand.Int63n(int64(end.Sub(start)))))
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return renewTime, nil
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}
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// certStore provides a way to perist and retrieve TLS certificates.
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// As of 2023-02-01, we use store certs in directories on disk everywhere
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// except on Kubernetes, where we use the state store.
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type certStore interface {
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// Read returns the cert and key for domain, if they exist and are valid
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// for now. If they're expired, it returns errCertExpired.
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// If they don't exist, it returns ipn.ErrStateNotExist.
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Read(domain string, now time.Time) (*TLSCertKeyPair, error)
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// WriteCert writes the cert for domain.
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WriteCert(domain string, cert []byte) error
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// WriteKey writes the key for domain.
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WriteKey(domain string, key []byte) error
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// ACMEKey returns the value previously stored via WriteACMEKey.
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// It is a PEM encoded ECDSA key.
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ACMEKey() ([]byte, error)
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// WriteACMEKey stores the provided PEM encoded ECDSA key.
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WriteACMEKey([]byte) error
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}
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var errCertExpired = errors.New("cert expired")
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var testX509Roots *x509.CertPool // set non-nil by tests
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func (b *LocalBackend) getCertStore() (certStore, error) {
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switch b.store.(type) {
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case *store.FileStore:
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case *mem.Store:
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default:
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if hostinfo.GetEnvType() == hostinfo.Kubernetes {
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// We're running in Kubernetes with a custom StateStore,
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// use that instead of the cert directory.
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// TODO(maisem): expand this to other environments?
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return certStateStore{StateStore: b.store}, nil
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}
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}
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dir, err := b.certDir()
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if err != nil {
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return nil, err
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}
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if testX509Roots != nil && !testenv.InTest() {
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panic("use of test hook outside of tests")
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}
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return certFileStore{dir: dir, testRoots: testX509Roots}, nil
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}
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// certFileStore implements certStore by storing the cert & key files in the named directory.
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type certFileStore struct {
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dir string
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// This field allows a test to override the CA root(s) for certificate
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// verification. If nil the default system pool is used.
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testRoots *x509.CertPool
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}
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const acmePEMName = "acme-account.key.pem"
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func (f certFileStore) ACMEKey() ([]byte, error) {
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pemName := filepath.Join(f.dir, acmePEMName)
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v, err := os.ReadFile(pemName)
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if err != nil {
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if os.IsNotExist(err) {
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return nil, ipn.ErrStateNotExist
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}
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return nil, err
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}
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return v, nil
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}
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func (f certFileStore) WriteACMEKey(b []byte) error {
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pemName := filepath.Join(f.dir, acmePEMName)
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return atomicfile.WriteFile(pemName, b, 0600)
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}
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func (f certFileStore) Read(domain string, now time.Time) (*TLSCertKeyPair, error) {
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certPEM, err := os.ReadFile(certFile(f.dir, domain))
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if err != nil {
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if os.IsNotExist(err) {
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return nil, ipn.ErrStateNotExist
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}
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return nil, err
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}
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keyPEM, err := os.ReadFile(keyFile(f.dir, domain))
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if err != nil {
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if os.IsNotExist(err) {
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return nil, ipn.ErrStateNotExist
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}
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return nil, err
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}
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if !validCertPEM(domain, keyPEM, certPEM, f.testRoots, now) {
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return nil, errCertExpired
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}
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return &TLSCertKeyPair{CertPEM: certPEM, KeyPEM: keyPEM, Cached: true}, nil
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}
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func (f certFileStore) WriteCert(domain string, cert []byte) error {
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return atomicfile.WriteFile(certFile(f.dir, domain), cert, 0644)
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}
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func (f certFileStore) WriteKey(domain string, key []byte) error {
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return atomicfile.WriteFile(keyFile(f.dir, domain), key, 0600)
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}
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// certStateStore implements certStore by storing the cert & key files in an ipn.StateStore.
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type certStateStore struct {
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ipn.StateStore
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// This field allows a test to override the CA root(s) for certificate
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// verification. If nil the default system pool is used.
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testRoots *x509.CertPool
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}
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func (s certStateStore) Read(domain string, now time.Time) (*TLSCertKeyPair, error) {
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certPEM, err := s.ReadState(ipn.StateKey(domain + ".crt"))
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if err != nil {
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return nil, err
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}
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keyPEM, err := s.ReadState(ipn.StateKey(domain + ".key"))
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if err != nil {
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return nil, err
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}
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if !validCertPEM(domain, keyPEM, certPEM, s.testRoots, now) {
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return nil, errCertExpired
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}
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return &TLSCertKeyPair{CertPEM: certPEM, KeyPEM: keyPEM, Cached: true}, nil
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}
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func (s certStateStore) WriteCert(domain string, cert []byte) error {
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return ipn.WriteState(s.StateStore, ipn.StateKey(domain+".crt"), cert)
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}
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func (s certStateStore) WriteKey(domain string, key []byte) error {
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return ipn.WriteState(s.StateStore, ipn.StateKey(domain+".key"), key)
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}
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func (s certStateStore) ACMEKey() ([]byte, error) {
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return s.ReadState(ipn.StateKey(acmePEMName))
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}
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func (s certStateStore) WriteACMEKey(key []byte) error {
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return ipn.WriteState(s.StateStore, ipn.StateKey(acmePEMName), key)
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}
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// TLSCertKeyPair is a TLS public and private key, and whether they were obtained
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// from cache or freshly obtained.
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type TLSCertKeyPair struct {
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CertPEM []byte // public key, in PEM form
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KeyPEM []byte // private key, in PEM form
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Cached bool // whether result came from cache
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}
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func keyFile(dir, domain string) string { return filepath.Join(dir, domain+".key") }
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func certFile(dir, domain string) string { return filepath.Join(dir, domain+".crt") }
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// getCertPEMCached returns a non-nil keyPair if a cached keypair for domain
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// exists on disk in dir that is valid at the provided now time.
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//
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// If the keypair is expired, it returns errCertExpired.
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// If the keypair doesn't exist, it returns ipn.ErrStateNotExist.
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func getCertPEMCached(cs certStore, domain string, now time.Time) (p *TLSCertKeyPair, err error) {
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if !validLookingCertDomain(domain) {
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// Before we read files from disk using it, validate it's halfway
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// reasonable looking.
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return nil, fmt.Errorf("invalid domain %q", domain)
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}
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return cs.Read(domain, now)
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}
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func (b *LocalBackend) getCertPEM(ctx context.Context, cs certStore, logf logger.Logf, traceACME func(any), domain string, now time.Time) (*TLSCertKeyPair, error) {
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acmeMu.Lock()
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defer acmeMu.Unlock()
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// In case this method was triggered multiple times in parallel (when
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// serving incoming requests), check whether one of the other goroutines
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// already renewed the cert before us.
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if p, err := getCertPEMCached(cs, domain, now); err == nil {
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// shouldStartDomainRenewal caches its result so it's OK to call this
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// frequently.
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shouldRenew, err := b.shouldStartDomainRenewal(cs, domain, now, p)
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if err != nil {
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logf("error checking for certificate renewal: %v", err)
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} else if !shouldRenew {
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return p, nil
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}
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} else if !errors.Is(err, ipn.ErrStateNotExist) && !errors.Is(err, errCertExpired) {
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return nil, err
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}
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ac, err := acmeClient(cs)
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if err != nil {
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return nil, err
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}
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a, err := ac.GetReg(ctx, "" /* pre-RFC param */)
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switch {
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case err == nil:
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// Great, already registered.
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logf("already had ACME account.")
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case err == acme.ErrNoAccount:
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a, err = ac.Register(ctx, new(acme.Account), acme.AcceptTOS)
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if err == acme.ErrAccountAlreadyExists {
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// Potential race. Double check.
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a, err = ac.GetReg(ctx, "" /* pre-RFC param */)
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}
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if err != nil {
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return nil, fmt.Errorf("acme.Register: %w", err)
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}
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logf("registered ACME account.")
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traceACME(a)
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default:
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return nil, fmt.Errorf("acme.GetReg: %w", err)
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}
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if a.Status != acme.StatusValid {
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return nil, fmt.Errorf("unexpected ACME account status %q", a.Status)
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}
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// Before hitting LetsEncrypt, see if this is a domain that Tailscale will do DNS challenges for.
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st := b.StatusWithoutPeers()
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if err := checkCertDomain(st, domain); err != nil {
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return nil, err
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}
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order, err := ac.AuthorizeOrder(ctx, []acme.AuthzID{{Type: "dns", Value: domain}})
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if err != nil {
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return nil, err
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}
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traceACME(order)
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for _, aurl := range order.AuthzURLs {
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az, err := ac.GetAuthorization(ctx, aurl)
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if err != nil {
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return nil, err
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}
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traceACME(az)
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for _, ch := range az.Challenges {
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if ch.Type == "dns-01" {
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rec, err := ac.DNS01ChallengeRecord(ch.Token)
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if err != nil {
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return nil, err
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}
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key := "_acme-challenge." + domain
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// Do a best-effort lookup to see if we've already created this DNS name
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// in a previous attempt. Don't burn too much time on it, though. Worst
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// case we ask the server to create something that already exists.
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var resolver net.Resolver
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lookupCtx, lookupCancel := context.WithTimeout(ctx, 500*time.Millisecond)
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txts, _ := resolver.LookupTXT(lookupCtx, key)
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lookupCancel()
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if slices.Contains(txts, rec) {
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logf("TXT record already existed")
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} else {
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logf("starting SetDNS call...")
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err = b.SetDNS(ctx, key, rec)
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if err != nil {
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return nil, fmt.Errorf("SetDNS %q => %q: %w", key, rec, err)
|
|
}
|
|
logf("did SetDNS")
|
|
}
|
|
|
|
chal, err := ac.Accept(ctx, ch)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("Accept: %v", err)
|
|
}
|
|
traceACME(chal)
|
|
break
|
|
}
|
|
}
|
|
}
|
|
|
|
orderURI := order.URI
|
|
order, err = ac.WaitOrder(ctx, orderURI)
|
|
if err != nil {
|
|
if ctx.Err() != nil {
|
|
return nil, ctx.Err()
|
|
}
|
|
if oe, ok := err.(*acme.OrderError); ok {
|
|
logf("acme: WaitOrder: OrderError status %q", oe.Status)
|
|
} else {
|
|
logf("acme: WaitOrder error: %v", err)
|
|
}
|
|
return nil, err
|
|
}
|
|
traceACME(order)
|
|
|
|
certPrivKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
var privPEM bytes.Buffer
|
|
if err := encodeECDSAKey(&privPEM, certPrivKey); err != nil {
|
|
return nil, err
|
|
}
|
|
if err := cs.WriteKey(domain, privPEM.Bytes()); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
csr, err := certRequest(certPrivKey, domain, nil)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
logf("requesting cert...")
|
|
der, _, err := ac.CreateOrderCert(ctx, order.FinalizeURL, csr, true)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("CreateOrder: %v", err)
|
|
}
|
|
logf("got cert")
|
|
|
|
var certPEM bytes.Buffer
|
|
for _, b := range der {
|
|
pb := &pem.Block{Type: "CERTIFICATE", Bytes: b}
|
|
if err := pem.Encode(&certPEM, pb); err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
if err := cs.WriteCert(domain, certPEM.Bytes()); err != nil {
|
|
return nil, err
|
|
}
|
|
b.domainRenewed(domain)
|
|
|
|
return &TLSCertKeyPair{CertPEM: certPEM.Bytes(), KeyPEM: privPEM.Bytes()}, 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)
|
|
}
|
|
|
|
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)
|
|
}
|
|
|
|
// parsePrivateKey is a copy of x/crypto/acme's parsePrivateKey.
|
|
//
|
|
// 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")
|
|
}
|
|
|
|
func acmeKey(cs certStore) (crypto.Signer, error) {
|
|
if v, err := cs.ACMEKey(); err == nil {
|
|
priv, _ := pem.Decode(v)
|
|
if priv == nil || !strings.Contains(priv.Type, "PRIVATE") {
|
|
return nil, errors.New("acme/autocert: invalid account key found in cache")
|
|
}
|
|
return parsePrivateKey(priv.Bytes)
|
|
} else if !errors.Is(err, ipn.ErrStateNotExist) {
|
|
return nil, err
|
|
}
|
|
|
|
privKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
var pemBuf bytes.Buffer
|
|
if err := encodeECDSAKey(&pemBuf, privKey); err != nil {
|
|
return nil, err
|
|
}
|
|
if err := cs.WriteACMEKey(pemBuf.Bytes()); err != nil {
|
|
return nil, err
|
|
}
|
|
return privKey, nil
|
|
}
|
|
|
|
func acmeClient(cs certStore) (*acme.Client, error) {
|
|
key, err := acmeKey(cs)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("acmeKey: %w", err)
|
|
}
|
|
// Note: if we add support for additional ACME providers (other than
|
|
// LetsEncrypt), we should make sure that they support ARI extension (see
|
|
// shouldStartDomainRenewalARI).
|
|
return &acme.Client{
|
|
Key: key,
|
|
UserAgent: "tailscaled/" + version.Long(),
|
|
}, nil
|
|
}
|
|
|
|
// validCertPEM reports whether the given certificate is valid for domain at now.
|
|
//
|
|
// If roots != nil, it is used instead of the system root pool. This is meant
|
|
// to support testing, and production code should pass roots == nil.
|
|
func validCertPEM(domain string, keyPEM, certPEM []byte, roots *x509.CertPool, now time.Time) bool {
|
|
if len(keyPEM) == 0 || len(certPEM) == 0 {
|
|
return false
|
|
}
|
|
tlsCert, err := tls.X509KeyPair(certPEM, keyPEM)
|
|
if err != nil {
|
|
return false
|
|
}
|
|
|
|
var leaf *x509.Certificate
|
|
intermediates := x509.NewCertPool()
|
|
for i, certDER := range tlsCert.Certificate {
|
|
cert, err := x509.ParseCertificate(certDER)
|
|
if err != nil {
|
|
return false
|
|
}
|
|
if i == 0 {
|
|
leaf = cert
|
|
} else {
|
|
intermediates.AddCert(cert)
|
|
}
|
|
}
|
|
if leaf == nil {
|
|
return false
|
|
}
|
|
_, err = leaf.Verify(x509.VerifyOptions{
|
|
DNSName: domain,
|
|
CurrentTime: now,
|
|
Roots: roots,
|
|
Intermediates: intermediates,
|
|
})
|
|
return err == nil
|
|
}
|
|
|
|
// validLookingCertDomain reports whether name looks like a valid domain name that
|
|
// we might be able to get a cert for.
|
|
//
|
|
// It's a light check primarily for double checking before it's used
|
|
// as part of a filesystem path. The actual validation happens in checkCertDomain.
|
|
func validLookingCertDomain(name string) bool {
|
|
if name == "" ||
|
|
strings.Contains(name, "..") ||
|
|
strings.ContainsAny(name, ":/\\\x00") ||
|
|
!strings.Contains(name, ".") {
|
|
return false
|
|
}
|
|
return true
|
|
}
|
|
|
|
func checkCertDomain(st *ipnstate.Status, domain string) error {
|
|
if domain == "" {
|
|
return errors.New("missing domain name")
|
|
}
|
|
for _, d := range st.CertDomains {
|
|
if d == domain {
|
|
return nil
|
|
}
|
|
}
|
|
if len(st.CertDomains) == 0 {
|
|
return errors.New("your Tailscale account does not support getting TLS certs")
|
|
}
|
|
return fmt.Errorf("invalid domain %q; must be one of %q", domain, st.CertDomains)
|
|
}
|