forked from mirror/pages-server
381 lines
13 KiB
Go
381 lines
13 KiB
Go
package certificates
|
|
|
|
import (
|
|
"context"
|
|
"crypto/tls"
|
|
"crypto/x509"
|
|
"errors"
|
|
"fmt"
|
|
"strconv"
|
|
"strings"
|
|
"time"
|
|
|
|
"github.com/go-acme/lego/v4/certcrypto"
|
|
"github.com/go-acme/lego/v4/certificate"
|
|
"github.com/go-acme/lego/v4/challenge/tlsalpn01"
|
|
"github.com/go-acme/lego/v4/lego"
|
|
"github.com/reugn/equalizer"
|
|
"github.com/rs/zerolog/log"
|
|
|
|
"codeberg.org/codeberg/pages/server/cache"
|
|
"codeberg.org/codeberg/pages/server/database"
|
|
dnsutils "codeberg.org/codeberg/pages/server/dns"
|
|
"codeberg.org/codeberg/pages/server/gitea"
|
|
"codeberg.org/codeberg/pages/server/upstream"
|
|
)
|
|
|
|
var ErrUserRateLimitExceeded = errors.New("rate limit exceeded: 10 certificates per user per 24 hours")
|
|
|
|
// TLSConfig returns the configuration for generating, serving and cleaning up Let's Encrypt certificates.
|
|
func TLSConfig(mainDomainSuffix string,
|
|
giteaClient *gitea.Client,
|
|
acmeClient *AcmeClient,
|
|
firstDefaultBranch string,
|
|
keyCache, challengeCache, dnsLookupCache, canonicalDomainCache cache.SetGetKey,
|
|
certDB database.CertDB,
|
|
) *tls.Config {
|
|
return &tls.Config{
|
|
// check DNS name & get certificate from Let's Encrypt
|
|
GetCertificate: func(info *tls.ClientHelloInfo) (*tls.Certificate, error) {
|
|
domain := strings.ToLower(strings.TrimSpace(info.ServerName))
|
|
if len(domain) < 1 {
|
|
return nil, errors.New("missing domain info via SNI (RFC 4366, Section 3.1)")
|
|
}
|
|
|
|
// https request init is actually a acme challenge
|
|
if info.SupportedProtos != nil {
|
|
for _, proto := range info.SupportedProtos {
|
|
if proto != tlsalpn01.ACMETLS1Protocol {
|
|
continue
|
|
}
|
|
log.Info().Msgf("Detect ACME-TLS1 challenge for '%s'", domain)
|
|
|
|
challenge, ok := challengeCache.Get(domain)
|
|
if !ok {
|
|
return nil, errors.New("no challenge for this domain")
|
|
}
|
|
cert, err := tlsalpn01.ChallengeCert(domain, challenge.(string))
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return cert, nil
|
|
}
|
|
}
|
|
|
|
targetOwner := ""
|
|
mayObtainCert := true
|
|
if strings.HasSuffix(domain, mainDomainSuffix) || strings.EqualFold(domain, mainDomainSuffix[1:]) {
|
|
// deliver default certificate for the main domain (*.codeberg.page)
|
|
domain = mainDomainSuffix
|
|
} else {
|
|
var targetRepo, targetBranch string
|
|
targetOwner, targetRepo, targetBranch = dnsutils.GetTargetFromDNS(domain, mainDomainSuffix, firstDefaultBranch, dnsLookupCache)
|
|
if targetOwner == "" {
|
|
// DNS not set up, return main certificate to redirect to the docs
|
|
domain = mainDomainSuffix
|
|
} else {
|
|
targetOpt := &upstream.Options{
|
|
TargetOwner: targetOwner,
|
|
TargetRepo: targetRepo,
|
|
TargetBranch: targetBranch,
|
|
}
|
|
_, valid := targetOpt.CheckCanonicalDomain(giteaClient, domain, mainDomainSuffix, canonicalDomainCache)
|
|
if !valid {
|
|
// We shouldn't obtain a certificate when we cannot check if the
|
|
// repository has specified this domain in the `.domains` file.
|
|
mayObtainCert = false
|
|
}
|
|
}
|
|
}
|
|
|
|
if tlsCertificate, ok := keyCache.Get(domain); ok {
|
|
// we can use an existing certificate object
|
|
return tlsCertificate.(*tls.Certificate), nil
|
|
}
|
|
|
|
var tlsCertificate *tls.Certificate
|
|
var err error
|
|
if tlsCertificate, err = acmeClient.retrieveCertFromDB(domain, mainDomainSuffix, false, certDB); err != nil {
|
|
if !errors.Is(err, database.ErrNotFound) {
|
|
return nil, err
|
|
}
|
|
// we could not find a cert in db, request a new certificate
|
|
|
|
// first check if we are allowed to obtain a cert for this domain
|
|
if strings.EqualFold(domain, mainDomainSuffix) {
|
|
return nil, errors.New("won't request certificate for main domain, something really bad has happened")
|
|
}
|
|
if !mayObtainCert {
|
|
return nil, fmt.Errorf("won't request certificate for %q", domain)
|
|
}
|
|
|
|
tlsCertificate, err = acmeClient.obtainCert(acmeClient.legoClient, []string{domain}, nil, targetOwner, false, mainDomainSuffix, certDB)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
|
|
if err := keyCache.Set(domain, tlsCertificate, 15*time.Minute); err != nil {
|
|
return nil, err
|
|
}
|
|
return tlsCertificate, nil
|
|
},
|
|
NextProtos: []string{
|
|
"h2",
|
|
"http/1.1",
|
|
tlsalpn01.ACMETLS1Protocol,
|
|
},
|
|
|
|
// generated 2021-07-13, Mozilla Guideline v5.6, Go 1.14.4, intermediate configuration
|
|
// https://ssl-config.mozilla.org/#server=go&version=1.14.4&config=intermediate&guideline=5.6
|
|
MinVersion: tls.VersionTLS12,
|
|
CipherSuites: []uint16{
|
|
tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
|
|
tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
|
|
tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
|
|
tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
|
|
tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
|
|
tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
|
|
},
|
|
}
|
|
}
|
|
|
|
func (c *AcmeClient) checkUserLimit(user string) error {
|
|
userLimit, ok := c.acmeClientCertificateLimitPerUser[user]
|
|
if !ok {
|
|
// Each user can only add 10 new domains per day.
|
|
userLimit = equalizer.NewTokenBucket(10, time.Hour*24)
|
|
c.acmeClientCertificateLimitPerUser[user] = userLimit
|
|
}
|
|
if !userLimit.Ask() {
|
|
return fmt.Errorf("user '%s' error: %w", user, ErrUserRateLimitExceeded)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (c *AcmeClient) retrieveCertFromDB(sni, mainDomainSuffix string, useDnsProvider bool, certDB database.CertDB) (*tls.Certificate, error) {
|
|
// parse certificate from database
|
|
res, err := certDB.Get(sni)
|
|
if err != nil {
|
|
return nil, err
|
|
} else if res == nil {
|
|
return nil, database.ErrNotFound
|
|
}
|
|
|
|
tlsCertificate, err := tls.X509KeyPair(res.Certificate, res.PrivateKey)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// TODO: document & put into own function
|
|
if !strings.EqualFold(sni, mainDomainSuffix) {
|
|
tlsCertificate.Leaf, err = x509.ParseCertificate(tlsCertificate.Certificate[0])
|
|
if err != nil {
|
|
return nil, fmt.Errorf("error parsing leaf tlsCert: %w", err)
|
|
}
|
|
|
|
// renew certificates 7 days before they expire
|
|
if tlsCertificate.Leaf.NotAfter.Before(time.Now().Add(7 * 24 * time.Hour)) {
|
|
// TODO: use ValidTill of custom cert struct
|
|
if res.CSR != nil && len(res.CSR) > 0 {
|
|
// CSR stores the time when the renewal shall be tried again
|
|
nextTryUnix, err := strconv.ParseInt(string(res.CSR), 10, 64)
|
|
if err == nil && time.Now().Before(time.Unix(nextTryUnix, 0)) {
|
|
return &tlsCertificate, nil
|
|
}
|
|
}
|
|
// TODO: make a queue ?
|
|
go (func() {
|
|
res.CSR = nil // acme client doesn't like CSR to be set
|
|
if _, err := c.obtainCert(c.legoClient, []string{sni}, res, "", useDnsProvider, mainDomainSuffix, certDB); err != nil {
|
|
log.Error().Msgf("Couldn't renew certificate for %s: %v", sni, err)
|
|
}
|
|
})()
|
|
}
|
|
}
|
|
|
|
return &tlsCertificate, nil
|
|
}
|
|
|
|
func (c *AcmeClient) obtainCert(acmeClient *lego.Client, domains []string, renew *certificate.Resource, user string, useDnsProvider bool, mainDomainSuffix string, keyDatabase database.CertDB) (*tls.Certificate, error) {
|
|
name := strings.TrimPrefix(domains[0], "*")
|
|
if useDnsProvider && len(domains[0]) > 0 && domains[0][0] == '*' {
|
|
domains = domains[1:]
|
|
}
|
|
|
|
// lock to avoid simultaneous requests
|
|
_, working := c.obtainLocks.LoadOrStore(name, struct{}{})
|
|
if working {
|
|
for working {
|
|
time.Sleep(100 * time.Millisecond)
|
|
_, working = c.obtainLocks.Load(name)
|
|
}
|
|
cert, err := c.retrieveCertFromDB(name, mainDomainSuffix, useDnsProvider, keyDatabase)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("certificate failed in synchronous request: %w", err)
|
|
}
|
|
return cert, nil
|
|
}
|
|
defer c.obtainLocks.Delete(name)
|
|
|
|
if acmeClient == nil {
|
|
return mockCert(domains[0], "ACME client uninitialized. This is a server error, please report!", mainDomainSuffix, keyDatabase)
|
|
}
|
|
|
|
// request actual cert
|
|
var res *certificate.Resource
|
|
var err error
|
|
if renew != nil && renew.CertURL != "" {
|
|
if c.acmeUseRateLimits {
|
|
c.acmeClientRequestLimit.Take()
|
|
}
|
|
log.Debug().Msgf("Renewing certificate for: %v", domains)
|
|
res, err = acmeClient.Certificate.Renew(*renew, true, false, "")
|
|
if err != nil {
|
|
log.Error().Err(err).Msgf("Couldn't renew certificate for %v, trying to request a new one", domains)
|
|
if c.acmeUseRateLimits {
|
|
c.acmeClientFailLimit.Take()
|
|
}
|
|
res = nil
|
|
}
|
|
}
|
|
if res == nil {
|
|
if user != "" {
|
|
if err := c.checkUserLimit(user); err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
|
|
if c.acmeUseRateLimits {
|
|
c.acmeClientOrderLimit.Take()
|
|
c.acmeClientRequestLimit.Take()
|
|
}
|
|
log.Debug().Msgf("Re-requesting new certificate for %v", domains)
|
|
res, err = acmeClient.Certificate.Obtain(certificate.ObtainRequest{
|
|
Domains: domains,
|
|
Bundle: true,
|
|
MustStaple: false,
|
|
})
|
|
if c.acmeUseRateLimits && err != nil {
|
|
c.acmeClientFailLimit.Take()
|
|
}
|
|
}
|
|
if err != nil {
|
|
log.Error().Err(err).Msgf("Couldn't obtain again a certificate or %v", domains)
|
|
if renew != nil && renew.CertURL != "" {
|
|
tlsCertificate, err := tls.X509KeyPair(renew.Certificate, renew.PrivateKey)
|
|
if err != nil {
|
|
mockC, err2 := mockCert(domains[0], err.Error(), mainDomainSuffix, keyDatabase)
|
|
if err2 != nil {
|
|
return nil, errors.Join(err, err2)
|
|
}
|
|
return mockC, err
|
|
}
|
|
leaf, err := leaf(&tlsCertificate)
|
|
if err == nil && leaf.NotAfter.After(time.Now()) {
|
|
// avoid sending a mock cert instead of a still valid cert, instead abuse CSR field to store time to try again at
|
|
renew.CSR = []byte(strconv.FormatInt(time.Now().Add(6*time.Hour).Unix(), 10))
|
|
if err := keyDatabase.Put(name, renew); err != nil {
|
|
mockC, err2 := mockCert(domains[0], err.Error(), mainDomainSuffix, keyDatabase)
|
|
if err2 != nil {
|
|
return nil, errors.Join(err, err2)
|
|
}
|
|
return mockC, err
|
|
}
|
|
return &tlsCertificate, nil
|
|
}
|
|
}
|
|
return mockCert(domains[0], err.Error(), mainDomainSuffix, keyDatabase)
|
|
}
|
|
log.Debug().Msgf("Obtained certificate for %v", domains)
|
|
|
|
if err := keyDatabase.Put(name, res); err != nil {
|
|
return nil, err
|
|
}
|
|
tlsCertificate, err := tls.X509KeyPair(res.Certificate, res.PrivateKey)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &tlsCertificate, nil
|
|
}
|
|
|
|
func SetupMainDomainCertificates(mainDomainSuffix string, acmeClient *AcmeClient, certDB database.CertDB) error {
|
|
// getting main cert before ACME account so that we can fail here without hitting rate limits
|
|
mainCertBytes, err := certDB.Get(mainDomainSuffix)
|
|
if err != nil && !errors.Is(err, database.ErrNotFound) {
|
|
return fmt.Errorf("cert database is not working: %w", err)
|
|
}
|
|
|
|
if mainCertBytes == nil {
|
|
_, err = acmeClient.obtainCert(acmeClient.dnsChallengerLegoClient, []string{"*" + mainDomainSuffix, mainDomainSuffix[1:]}, nil, "", true, mainDomainSuffix, certDB)
|
|
if err != nil {
|
|
log.Error().Err(err).Msg("Couldn't renew main domain certificate, continuing with mock certs only")
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func MaintainCertDB(ctx context.Context, interval time.Duration, acmeClient *AcmeClient, mainDomainSuffix string, certDB database.CertDB) {
|
|
for {
|
|
// delete expired certs that will be invalid until next clean up
|
|
threshold := time.Now().Add(interval)
|
|
expiredCertCount := 0
|
|
|
|
certs, err := certDB.Items(0, 0)
|
|
if err != nil {
|
|
log.Error().Err(err).Msg("could not get certs from list")
|
|
} else {
|
|
for _, cert := range certs {
|
|
if !strings.EqualFold(cert.Domain, strings.TrimPrefix(mainDomainSuffix, ".")) {
|
|
if time.Unix(cert.ValidTill, 0).Before(threshold) {
|
|
err := certDB.Delete(cert.Domain)
|
|
if err != nil {
|
|
log.Error().Err(err).Msgf("Deleting expired certificate for %q failed", cert.Domain)
|
|
} else {
|
|
expiredCertCount++
|
|
}
|
|
}
|
|
}
|
|
}
|
|
log.Debug().Msgf("Removed %d expired certificates from the database", expiredCertCount)
|
|
}
|
|
|
|
// update main cert
|
|
res, err := certDB.Get(mainDomainSuffix)
|
|
if err != nil {
|
|
log.Error().Msgf("Couldn't get cert for domain %q", mainDomainSuffix)
|
|
} else if res == nil {
|
|
log.Error().Msgf("Couldn't renew certificate for main domain %q expected main domain cert to exist, but it's missing - seems like the database is corrupted", mainDomainSuffix)
|
|
} else {
|
|
tlsCertificates, err := certcrypto.ParsePEMBundle(res.Certificate)
|
|
if err != nil {
|
|
log.Error().Err(fmt.Errorf("could not parse cert for mainDomainSuffix: %w", err))
|
|
} else if tlsCertificates[0].NotAfter.Before(time.Now().Add(30 * 24 * time.Hour)) {
|
|
// renew main certificate 30 days before it expires
|
|
go (func() {
|
|
_, err = acmeClient.obtainCert(acmeClient.dnsChallengerLegoClient, []string{"*" + mainDomainSuffix, mainDomainSuffix[1:]}, res, "", true, mainDomainSuffix, certDB)
|
|
if err != nil {
|
|
log.Error().Err(err).Msg("Couldn't renew certificate for main domain")
|
|
}
|
|
})()
|
|
}
|
|
}
|
|
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
case <-time.After(interval):
|
|
}
|
|
}
|
|
}
|
|
|
|
// leaf returns the parsed leaf certificate, either from c.leaf or by parsing
|
|
// the corresponding c.Certificate[0].
|
|
func leaf(c *tls.Certificate) (*x509.Certificate, error) {
|
|
if c.Leaf != nil {
|
|
return c.Leaf, nil
|
|
}
|
|
return x509.ParseCertificate(c.Certificate[0])
|
|
}
|