local-server/ssl.go
2018-06-16 22:45:27 +11:00

196 lines
4.8 KiB
Go

package main
import (
"bytes"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"crypto/x509"
"crypto/x509/pkix"
"encoding/pem"
"fmt"
"log"
"math/big"
"net"
"time"
"github.com/cloudflare/cfssl/config"
"novit.nc/direktil/pkg/clustersconfig"
)
const (
// From Kubernetes:
// ECPrivateKeyBlockType is a possible value for pem.Block.Type.
ECPrivateKeyBlockType = "EC PRIVATE KEY"
)
func sslConfig(cfg *clustersconfig.Config) (*config.Config, error) {
return config.LoadConfig([]byte(cfg.SSLConfig))
}
func PrivateKeyPEM() (*ecdsa.PrivateKey, []byte) {
key, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
if err != nil {
log.Fatal("Failed to generate the key: ", err)
}
b, err := x509.MarshalECPrivateKey(key)
if err != nil {
log.Fatal("Unable to mashal EC key: ", err)
}
buf := &bytes.Buffer{}
if err := pem.Encode(buf, &pem.Block{
Type: ECPrivateKeyBlockType,
Bytes: b,
}); err != nil {
log.Fatal("Failed to write encode key: ", err)
}
return key, buf.Bytes()
}
func SelfSignedCertificatePEM(ttlYears int, key *ecdsa.PrivateKey) []byte {
notBefore := time.Now()
notAfter := notBefore.AddDate(ttlYears, 0, 0).Truncate(24 * time.Hour)
serialNumber, err := rand.Int(rand.Reader, big.NewInt(0xffffffff))
if err != nil {
log.Fatal("Failed to generate serial number: ", err)
}
certTemplate := &x509.Certificate{
SerialNumber: serialNumber,
NotBefore: notBefore,
NotAfter: notAfter,
IsCA: true,
Subject: pkix.Name{},
KeyUsage: x509.KeyUsageCertSign | x509.KeyUsageCRLSign | x509.KeyUsageDigitalSignature,
ExtKeyUsage: []x509.ExtKeyUsage{},
BasicConstraintsValid: true,
}
parentTemplate := certTemplate // self-signed
publicKey := key.Public()
derBytes, err := x509.CreateCertificate(rand.Reader, certTemplate, parentTemplate, publicKey, key)
if err != nil {
log.Fatal("Failed to generate certificate: ", err)
}
buf := &bytes.Buffer{}
if err := pem.Encode(buf, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes}); err != nil {
log.Fatal("Failed to write certificate: ", err)
}
return buf.Bytes()
}
func HostCertificatePEM(ttlYears int, key *ecdsa.PrivateKey, ctx *renderContext) ([]byte, error) {
caKey, err := loadPrivateKey("ca", ctx)
if err != nil {
return nil, err
}
caCrt, err := loadCertificate("ca", ctx)
if err != nil {
return nil, err
}
notBefore := time.Now()
notAfter := notBefore.AddDate(ttlYears, 0, 0).Truncate(24 * time.Hour)
serialNumber, err := rand.Int(rand.Reader, big.NewInt(0xffffffff))
if err != nil {
log.Fatal("Failed to generate serial number: ", err)
}
dnsNames := []string{ctx.Host.Name}
ips := []net.IP{net.ParseIP(ctx.Host.IP)}
if ctx.Group.Master {
dnsNames = append(dnsNames,
"kubernetes",
"kubernetes.kube-system",
"kubernetes.kube-system.svc."+ctx.Cluster.Domain,
)
ips = append(ips, ctx.Cluster.KubernetesSvcIP())
}
certTemplate := &x509.Certificate{
SerialNumber: serialNumber,
NotBefore: notBefore,
NotAfter: notAfter,
IsCA: false,
Subject: pkix.Name{
CommonName: ctx.Host.Name,
},
KeyUsage: x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth, x509.ExtKeyUsageServerAuth},
DNSNames: dnsNames,
IPAddresses: ips,
}
parentTemplate := caCrt
publicKey := key.Public()
derBytes, err := x509.CreateCertificate(rand.Reader, certTemplate, parentTemplate, publicKey, caKey)
if err != nil {
log.Fatal("Failed to generate certificate: ", err)
}
f := &bytes.Buffer{}
if err := pem.Encode(f, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes}); err != nil {
log.Fatal("Failed to write certificate: ", err)
}
return f.Bytes(), nil
}
func loadPrivateKey(path string, ctx *renderContext) (*ecdsa.PrivateKey, error) {
keyS, err := getSecret("tls-key:"+path, ctx)
if err != nil {
return nil, err
}
keyBytes := []byte(keyS)
if len(keyBytes) == 0 {
return nil, fmt.Errorf("%s is empty", path)
}
p, _ := pem.Decode(keyBytes)
if p.Type != ECPrivateKeyBlockType {
return nil, fmt.Errorf("wrong type in %s: %s", path, p.Type)
}
key, err := x509.ParseECPrivateKey(p.Bytes)
if err != nil {
return nil, fmt.Errorf("unable to parse key in %s: %v", path, err)
}
return key, nil
}
func loadCertificate(path string, ctx *renderContext) (*x509.Certificate, error) {
crtS, err := getSecret("tls-self-signed-cert:"+path, ctx)
if err != nil {
return nil, err
}
crtBytes := []byte(crtS)
if len(crtBytes) == 0 {
return nil, fmt.Errorf("%s is empty", path)
}
p, _ := pem.Decode(crtBytes)
if p.Type != "CERTIFICATE" {
return nil, fmt.Errorf("wrong type in %s: %s", path, p.Type)
}
crt, err := x509.ParseCertificate(p.Bytes)
if err != nil {
return nil, fmt.Errorf("unable to parse certificate in %s: %v", path, err)
}
return crt, nil
}