131 lines
3.2 KiB
Go
131 lines
3.2 KiB
Go
package gemini
|
|
|
|
import (
|
|
"bytes"
|
|
"crypto/ed25519"
|
|
"crypto/rand"
|
|
"crypto/x509"
|
|
"encoding/pem"
|
|
"math/big"
|
|
"net"
|
|
"os"
|
|
"strings"
|
|
"time"
|
|
)
|
|
|
|
// CertificateStore maps hostnames to certificates.
|
|
type CertificateStore struct {
|
|
store map[string]*x509.Certificate // map of hostnames to certificates
|
|
}
|
|
|
|
func NewCertificateStore() *CertificateStore {
|
|
return &CertificateStore{
|
|
store: map[string]*x509.Certificate{},
|
|
}
|
|
}
|
|
|
|
func (c *CertificateStore) Put(hostname string, cert *x509.Certificate) {
|
|
c.store[hostname] = cert
|
|
}
|
|
|
|
func (c *CertificateStore) Get(hostname string) *x509.Certificate {
|
|
return c.store[hostname]
|
|
}
|
|
|
|
// NewCertificate creates and returns a raw certificate for the given host.
|
|
// It generates a self-signed TLS certificate and a ED25519 private key.
|
|
func NewCertificate(host string) (crt, key []byte, err error) {
|
|
// Generate a ED25519 private key
|
|
_, priv, err := ed25519.GenerateKey(rand.Reader)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
public := priv.Public().(ed25519.PublicKey)
|
|
|
|
// ED25519 keys should have the DigitalSignature KeyUsage bits set
|
|
// in the x509.Certificate template
|
|
keyUsage := x509.KeyUsageDigitalSignature
|
|
|
|
notBefore := time.Now()
|
|
validFor := 365 * 24 * time.Hour
|
|
notAfter := notBefore.Add(validFor)
|
|
|
|
// Generate the serial number
|
|
serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
|
|
serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
|
|
template := x509.Certificate{
|
|
SerialNumber: serialNumber,
|
|
NotBefore: notBefore,
|
|
NotAfter: notAfter,
|
|
KeyUsage: keyUsage,
|
|
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
|
|
BasicConstraintsValid: true,
|
|
}
|
|
|
|
hosts := strings.Split(host, ",")
|
|
for _, h := range hosts {
|
|
if ip := net.ParseIP(h); ip != nil {
|
|
template.IPAddresses = append(template.IPAddresses, ip)
|
|
} else {
|
|
template.DNSNames = append(template.DNSNames, h)
|
|
}
|
|
}
|
|
|
|
// Create the certificate
|
|
cert, err := x509.CreateCertificate(rand.Reader, &template, &template, public, priv)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
|
|
// Encode the certificate
|
|
var b bytes.Buffer
|
|
if err := pem.Encode(&b, &pem.Block{Type: "CERTIFICATE", Bytes: cert}); err != nil {
|
|
return nil, nil, err
|
|
}
|
|
crt = b.Bytes()
|
|
|
|
// Encode the key
|
|
b = bytes.Buffer{}
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
privBytes, err := x509.MarshalPKCS8PrivateKey(priv)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
if err := pem.Encode(&b, &pem.Block{Type: "PRIVATE KEY", Bytes: privBytes}); err != nil {
|
|
return nil, nil, err
|
|
}
|
|
key = b.Bytes()
|
|
|
|
return
|
|
}
|
|
|
|
// WriteCertificate writes the provided certificate and private key to name.crt + name.key
|
|
func WriteCertificate(name string, crt, key []byte) error {
|
|
// Write the certificate
|
|
crtPath := name + ".crt"
|
|
crtOut, err := os.OpenFile(crtPath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0600)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if _, err := crtOut.Write(crt); err != nil {
|
|
return err
|
|
}
|
|
|
|
// Write the private key
|
|
keyPath := name + ".key"
|
|
keyOut, err := os.OpenFile(keyPath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0600)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if _, err := keyOut.Write(key); err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|