caddy/modules/caddypki/maintain.go

108 lines
2.7 KiB
Go

// Copyright 2015 Matthew Holt and The Caddy Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package caddypki
import (
"crypto/x509"
"fmt"
"log"
"runtime/debug"
"time"
"go.uber.org/zap"
)
func (p *PKI) maintenance() {
defer func() {
if err := recover(); err != nil {
log.Printf("[PANIC] PKI maintenance: %v\n%s", err, debug.Stack())
}
}()
ticker := time.NewTicker(10 * time.Minute) // TODO: make configurable
defer ticker.Stop()
for {
select {
case <-ticker.C:
p.renewCerts()
case <-p.ctx.Done():
return
}
}
}
func (p *PKI) renewCerts() {
for _, ca := range p.CAs {
err := p.renewCertsForCA(ca)
if err != nil {
p.log.Error("renewing intermediate certificates",
zap.Error(err),
zap.String("ca", ca.ID))
}
}
}
func (p *PKI) renewCertsForCA(ca *CA) error {
ca.mu.Lock()
defer ca.mu.Unlock()
log := p.log.With(zap.String("ca", ca.ID))
// only maintain the root if it's not manually provided in the config
if ca.Root == nil {
if needsRenewal(ca.root) {
// TODO: implement root renewal (use same key)
log.Warn("root certificate expiring soon (FIXME: ROOT RENEWAL NOT YET IMPLEMENTED)",
zap.Duration("time_remaining", time.Until(ca.inter.NotAfter)),
)
}
}
// only maintain the intermediate if it's not manually provided in the config
if ca.Intermediate == nil {
if needsRenewal(ca.inter) {
log.Info("intermediate expires soon; renewing",
zap.Duration("time_remaining", time.Until(ca.inter.NotAfter)),
)
rootCert, rootKey, err := ca.loadOrGenRoot()
if err != nil {
return fmt.Errorf("loading root key: %v", err)
}
interCert, interKey, err := ca.genIntermediate(rootCert, rootKey)
if err != nil {
return fmt.Errorf("generating new certificate: %v", err)
}
ca.inter, ca.interKey = interCert, interKey
log.Info("renewed intermediate",
zap.Time("new_expiration", ca.inter.NotAfter),
)
}
}
return nil
}
func needsRenewal(cert *x509.Certificate) bool {
lifetime := cert.NotAfter.Sub(cert.NotBefore)
renewalWindow := time.Duration(float64(lifetime) * renewalWindowRatio)
renewalWindowStart := cert.NotAfter.Add(-renewalWindow)
return time.Now().After(renewalWindowStart)
}
const renewalWindowRatio = 0.2 // TODO: make configurable