TLS certificates: Jarl obtains and renews them over ACME

Jarl is now an ACME client (lego's core, no DNS providers). It answers
DNS-01 challenges in a zone it serves, or through Porkbun's DNS API while
Porkbun serves the domain; "auto" decides from the domain's public name
servers at every renewal, and a CNAME on _acme-challenge is followed.
Certificates are used for jarld's HTTPS (served without a restart; each
port speaks HTTPS and plain HTTP, plain HTTP from loopback and trusted
proxies still served) and/or written for named's DNS over TLS/HTTPS, with
rndc reconfig on renewal. Renewal follows the CA's ARI window or two
thirds of the lifetime, with back-off. Certificates you renew yourself
can be used too. Certificates page and dashboard card, jarl cert,
/api/v1/certificates, Prometheus gauges, docs/certificates.md, and an
e2e section against Pebble.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

cmd/jarld/main.go

@@ -24,6 +24,7 @@ import (
 
 	"jarl/internal/auth"
 	"jarl/internal/bind"
+	"jarl/internal/certs"
 	"jarl/internal/config"
 	"jarl/internal/engine"
 	"jarl/internal/model"
@@ -310,6 +311,18 @@ func serveCmd() *cobra.Command {
 					a.log.Warn("the configuration file holds metrics.token and everyone can read it; make it readable only by root and jarld (chown root:jarl, chmod 640)", "file", configPath)
 				}
 			}
+			cm := certs.New(certs.Config{
+				Directory: a.cfg.ACME.Account.DirectoryURL(), Email: a.cfg.ACME.Account.Email, AgreeTOS: a.cfg.ACME.Account.AgreeTOS,
+				EABKeyID: a.cfg.ACME.Account.EABKeyID, EABHMAC: a.cfg.ACME.Account.EABHMAC,
+				Resolvers: a.cfg.ACME.Resolvers, CABundle: a.cfg.ACME.CABundle, CheckPropagation: a.cfg.ACME.CheckPropagation,
+				Dir: a.cfg.CertDir(), Version: version.String(), Porkbun: pb, PorkbunAllows: a.cfg.Porkbun.Allows,
+			}, a.store, a.eng, a.log)
+			cm.Start(ctx)
+			if a.cfg.ACME.Account.EABHMAC != "" {
+				if fi, err := os.Stat(configPath); err == nil && fi.Mode().Perm()&0o004 != 0 {
+					a.log.Warn("the configuration file holds acme.account.eab_hmac and everyone can read it; make it readable only by root and jarld (chown root:jarl, chmod 640)", "file", configPath)
+				}
+			}
 			srv := server.New(server.Config{
 				Listen: a.cfg.Listen, TLSCertFile: a.cfg.TLS.CertFile, TLSKeyFile: a.cfg.TLS.KeyFile,
 				TrustedProxies: a.cfg.Proxies(), SessionLifetime: time.Duration(a.cfg.Session.Lifetime),
@@ -320,6 +333,7 @@ func serveCmd() *cobra.Command {
 				TOTPRequire: a.cfg.TOTP.Require, TOTPIssuer: a.cfg.TOTP.IssuerName(),
 				Metrics: server.Metrics{Enabled: a.cfg.Metrics.Enabled, Listen: a.cfg.Metrics.Listen,
 					Allow: a.cfg.Metrics.AllowPrefixes(), Token: a.cfg.Metrics.Token},
+				Certs: cm,
 				HTTPReq: server.HTTPReq{
 					Enabled:           a.cfg.ACME.HTTPReq.Enabled,
 					AllowPlainHTTP:    !a.cfg.ACME.HTTPReq.RequireHTTPS,
@@ -337,6 +351,7 @@ func serveCmd() *cobra.Command {
 			}()
 			go auditRetention(ctx, a)
 			go blocklistLoop(ctx, a)
+			go cm.Run(ctx)
 			a.log.Info("jarld starting", "version", version.String(), "database", a.cfg.Database, "bind_config", a.cfg.BIND.ConfigDir)
 			err = srv.Serve(ctx, func() { sdNotify("READY=1\nSTATUS=serving") })
 			sdNotify("STOPPING=1")