goutils/cmd/certexpiry/main.go

101 lines
2.1 KiB
Go

package main
import (
"crypto/x509"
"crypto/x509/pkix"
"flag"
"fmt"
"io/ioutil"
"os"
"strings"
"time"
"git.wntrmute.dev/kyle/goutils/certlib"
"git.wntrmute.dev/kyle/goutils/die"
"git.wntrmute.dev/kyle/goutils/lib"
)
var warnOnly bool
var leeway = 2160 * time.Hour // three months
func displayName(name pkix.Name) string {
var ns []string
if name.CommonName != "" {
ns = append(ns, name.CommonName)
}
for i := range name.Country {
ns = append(ns, fmt.Sprintf("C=%s", name.Country[i]))
}
for i := range name.Organization {
ns = append(ns, fmt.Sprintf("O=%s", name.Organization[i]))
}
for i := range name.OrganizationalUnit {
ns = append(ns, fmt.Sprintf("OU=%s", name.OrganizationalUnit[i]))
}
for i := range name.Locality {
ns = append(ns, fmt.Sprintf("L=%s", name.Locality[i]))
}
for i := range name.Province {
ns = append(ns, fmt.Sprintf("ST=%s", name.Province[i]))
}
if len(ns) > 0 {
return "/" + strings.Join(ns, "/")
}
die.With("no subject information in root")
return ""
}
func expires(cert *x509.Certificate) time.Duration {
return cert.NotAfter.Sub(time.Now())
}
func inDanger(cert *x509.Certificate) bool {
return expires(cert) < leeway
}
func checkCert(cert *x509.Certificate) {
warn := inDanger(cert)
name := displayName(cert.Subject)
name = fmt.Sprintf("%s/SN=%s", name, cert.SerialNumber)
expiry := expires(cert)
if warnOnly {
if warn {
fmt.Fprintf(os.Stderr, "%s expires on %s (in %s)\n", name, cert.NotAfter, expiry)
}
} else {
fmt.Printf("%s expires on %s (in %s)\n", name, cert.NotAfter, expiry)
}
}
func main() {
flag.BoolVar(&warnOnly, "q", false, "only warn about expiring certs")
flag.DurationVar(&leeway, "t", leeway, "warn if certificates are closer than this to expiring")
flag.Parse()
for _, file := range flag.Args() {
in, err := ioutil.ReadFile(file)
if err != nil {
lib.Warn(err, "failed to read file")
continue
}
certs, err := certlib.ParseCertificatesPEM(in)
if err != nil {
lib.Warn(err, "while parsing certificates")
continue
}
for _, cert := range certs {
checkCert(cert)
}
}
}