telegraf/plugins/inputs/x509_cert/x509_cert.go

191 lines
4.3 KiB
Go

// Package x509_cert reports metrics from an SSL certificate.
package x509_cert
import (
"crypto/tls"
"crypto/x509"
"crypto/x509/pkix"
"encoding/pem"
"fmt"
"io/ioutil"
"net"
"net/url"
"strings"
"time"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/internal"
_tls "github.com/influxdata/telegraf/internal/tls"
"github.com/influxdata/telegraf/plugins/inputs"
)
const sampleConfig = `
## List certificate sources
sources = ["/etc/ssl/certs/ssl-cert-snakeoil.pem", "tcp://example.org:443"]
## Timeout for SSL connection
# timeout = "5s"
## Optional TLS Config
# tls_ca = "/etc/telegraf/ca.pem"
# tls_cert = "/etc/telegraf/cert.pem"
# tls_key = "/etc/telegraf/key.pem"
## Use TLS but skip chain & host verification
# insecure_skip_verify = false
`
const description = "Reads metrics from a SSL certificate"
// X509Cert holds the configuration of the plugin.
type X509Cert struct {
Sources []string `toml:"sources"`
Timeout internal.Duration `toml:"timeout"`
_tls.ClientConfig
}
// Description returns description of the plugin.
func (c *X509Cert) Description() string {
return description
}
// SampleConfig returns configuration sample for the plugin.
func (c *X509Cert) SampleConfig() string {
return sampleConfig
}
func (c *X509Cert) getCert(location string, timeout time.Duration) ([]*x509.Certificate, error) {
if strings.HasPrefix(location, "/") {
location = "file://" + location
}
u, err := url.Parse(location)
if err != nil {
return nil, fmt.Errorf("failed to parse cert location - %s\n", err.Error())
}
switch u.Scheme {
case "https":
u.Scheme = "tcp"
fallthrough
case "udp", "udp4", "udp6":
fallthrough
case "tcp", "tcp4", "tcp6":
tlsCfg, err := c.ClientConfig.TLSConfig()
if err != nil {
return nil, err
}
ipConn, err := net.DialTimeout(u.Scheme, u.Host, timeout)
if err != nil {
return nil, err
}
defer ipConn.Close()
if tlsCfg == nil {
tlsCfg = &tls.Config{}
}
tlsCfg.ServerName = u.Hostname()
conn := tls.Client(ipConn, tlsCfg)
defer conn.Close()
hsErr := conn.Handshake()
if hsErr != nil {
return nil, hsErr
}
certs := conn.ConnectionState().PeerCertificates
return certs, nil
case "file":
content, err := ioutil.ReadFile(u.Path)
if err != nil {
return nil, err
}
block, _ := pem.Decode(content)
if block == nil {
return nil, fmt.Errorf("failed to parse certificate PEM")
}
cert, err := x509.ParseCertificate(block.Bytes)
if err != nil {
return nil, err
}
return []*x509.Certificate{cert}, nil
default:
return nil, fmt.Errorf("unsuported scheme '%s' in location %s\n", u.Scheme, location)
}
}
func getFields(cert *x509.Certificate, now time.Time) map[string]interface{} {
age := int(now.Sub(cert.NotBefore).Seconds())
expiry := int(cert.NotAfter.Sub(now).Seconds())
startdate := cert.NotBefore.Unix()
enddate := cert.NotAfter.Unix()
fields := map[string]interface{}{
"age": age,
"expiry": expiry,
"startdate": startdate,
"enddate": enddate,
}
return fields
}
func getTags(subject pkix.Name, location string) map[string]string {
tags := map[string]string{
"source": location,
"common_name": subject.CommonName,
}
if len(subject.Organization) > 0 {
tags["organization"] = subject.Organization[0]
}
if len(subject.OrganizationalUnit) > 0 {
tags["organizational_unit"] = subject.OrganizationalUnit[0]
}
if len(subject.Country) > 0 {
tags["country"] = subject.Country[0]
}
if len(subject.Province) > 0 {
tags["province"] = subject.Province[0]
}
if len(subject.Locality) > 0 {
tags["locality"] = subject.Locality[0]
}
return tags
}
// Gather adds metrics into the accumulator.
func (c *X509Cert) Gather(acc telegraf.Accumulator) error {
now := time.Now()
for _, location := range c.Sources {
certs, err := c.getCert(location, c.Timeout.Duration*time.Second)
if err != nil {
return fmt.Errorf("cannot get SSL cert '%s': %s", location, err.Error())
}
for _, cert := range certs {
fields := getFields(cert, now)
tags := getTags(cert.Subject, location)
acc.AddFields("x509_cert", fields, tags)
}
}
return nil
}
func init() {
inputs.Add("x509_cert", func() telegraf.Input {
return &X509Cert{
Sources: []string{},
Timeout: internal.Duration{Duration: 5},
}
})
}