caddy/caddytls/selfsigned.go
Matthew Holt e0f1a02c37
Extract most of caddytls core code into external CertMagic package
All code relating to a caddytls.Config and setting it up from the
Caddyfile is still intact; only the certificate management-related
code was removed into a separate package.

I don't expect this to build in CI successfully; updating dependencies
and vendor is coming next.

I've also removed the ad-hoc, half-baked storage plugins that we need
to finish making first-class Caddy plugins (they were never documented
anyway). The new certmagic package has a much better storage interface,
and we can finally move toward making a new storage plugin type, but
it shouldn't be configurable in the Caddyfile, I think, since it doesn't
make sense for a Caddy instance to use more than one storage config...

We also have the option of eliminating DNS provider plugins and just
shipping all of lego's DNS providers by using a lego package (the
caddytls/setup.go file has a comment describing how) -- but it doubles
Caddy's binary size by 100% from about 19 MB to around 40 MB...!
2018-12-10 19:49:29 -07:00

107 lines
3.0 KiB
Go

package caddytls
import (
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"crypto/rsa"
"crypto/tls"
"crypto/x509"
"crypto/x509/pkix"
"fmt"
"math/big"
"net"
"strings"
"time"
"github.com/xenolf/lego/certcrypto"
)
// newSelfSignedCertificate returns a new self-signed certificate.
func newSelfSignedCertificate(ssconfig selfSignedConfig) (tls.Certificate, error) {
// start by generating private key
var privKey interface{}
var err error
switch ssconfig.KeyType {
case "", certcrypto.EC256:
privKey, err = ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
case certcrypto.EC384:
privKey, err = ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
case certcrypto.RSA2048:
privKey, err = rsa.GenerateKey(rand.Reader, 2048)
case certcrypto.RSA4096:
privKey, err = rsa.GenerateKey(rand.Reader, 4096)
case certcrypto.RSA8192:
privKey, err = rsa.GenerateKey(rand.Reader, 8192)
default:
return tls.Certificate{}, fmt.Errorf("cannot generate private key; unknown key type %v", ssconfig.KeyType)
}
if err != nil {
return tls.Certificate{}, fmt.Errorf("failed to generate private key: %v", err)
}
// create certificate structure with proper values
notBefore := time.Now()
notAfter := ssconfig.Expire
if notAfter.IsZero() || notAfter.Before(notBefore) {
notAfter = notBefore.Add(24 * time.Hour * 7)
}
serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
if err != nil {
return tls.Certificate{}, fmt.Errorf("failed to generate serial number: %v", err)
}
cert := &x509.Certificate{
SerialNumber: serialNumber,
Subject: pkix.Name{Organization: []string{"Caddy Self-Signed"}},
NotBefore: notBefore,
NotAfter: notAfter,
KeyUsage: x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
}
if len(ssconfig.SAN) == 0 {
ssconfig.SAN = []string{""}
}
var names []string
for _, san := range ssconfig.SAN {
if ip := net.ParseIP(san); ip != nil {
names = append(names, strings.ToLower(ip.String()))
cert.IPAddresses = append(cert.IPAddresses, ip)
} else {
names = append(names, strings.ToLower(san))
cert.DNSNames = append(cert.DNSNames, strings.ToLower(san))
}
}
// generate the associated public key
publicKey := func(privKey interface{}) interface{} {
switch k := privKey.(type) {
case *rsa.PrivateKey:
return &k.PublicKey
case *ecdsa.PrivateKey:
return &k.PublicKey
default:
return fmt.Errorf("unknown key type")
}
}
derBytes, err := x509.CreateCertificate(rand.Reader, cert, cert, publicKey(privKey), privKey)
if err != nil {
return tls.Certificate{}, fmt.Errorf("could not create certificate: %v", err)
}
chain := [][]byte{derBytes}
return tls.Certificate{
Certificate: chain,
PrivateKey: privKey,
Leaf: cert,
}, nil
}
// selfSignedConfig configures a self-signed certificate.
type selfSignedConfig struct {
SAN []string
KeyType certcrypto.KeyType
Expire time.Time
}