rename src/yggdrasil to src/core

src/core/tls.go

@@ -0,0 +1,93 @@
+package core
+
+import (
+	"bytes"
+	"crypto/ed25519"
+	"crypto/rand"
+	"crypto/tls"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/hex"
+	"encoding/pem"
+	"log"
+	"math/big"
+	"net"
+	"time"
+)
+
+type tcptls struct {
+	tcp         *tcp
+	config      *tls.Config
+	forDialer   *TcpUpgrade
+	forListener *TcpUpgrade
+}
+
+func (t *tcptls) init(tcp *tcp) {
+	t.tcp = tcp
+	t.forDialer = &TcpUpgrade{
+		upgrade: t.upgradeDialer,
+		name:    "tls",
+	}
+	t.forListener = &TcpUpgrade{
+		upgrade: t.upgradeListener,
+		name:    "tls",
+	}
+
+	edpriv := make(ed25519.PrivateKey, ed25519.PrivateKeySize)
+	copy(edpriv[:], tcp.links.core.secret[:])
+
+	certBuf := &bytes.Buffer{}
+
+	// TODO: because NotAfter is finite, we should add some mechanism to regenerate the certificate and restart the listeners periodically for nodes with very high uptimes. Perhaps regenerate certs and restart listeners every few months or so.
+	pubtemp := x509.Certificate{
+		SerialNumber: big.NewInt(1),
+		Subject: pkix.Name{
+			CommonName: hex.EncodeToString(tcp.links.core.public[:]),
+		},
+		NotBefore:             time.Now(),
+		NotAfter:              time.Now().Add(time.Hour * 24 * 365),
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		BasicConstraintsValid: true,
+	}
+
+	derbytes, err := x509.CreateCertificate(rand.Reader, &pubtemp, &pubtemp, edpriv.Public(), edpriv)
+	if err != nil {
+		log.Fatalf("Failed to create certificate: %s", err)
+	}
+
+	if err := pem.Encode(certBuf, &pem.Block{Type: "CERTIFICATE", Bytes: derbytes}); err != nil {
+		panic("failed to encode certificate into PEM")
+	}
+
+	cpool := x509.NewCertPool()
+	cpool.AppendCertsFromPEM(derbytes)
+
+	t.config = &tls.Config{
+		RootCAs: cpool,
+		Certificates: []tls.Certificate{
+			{
+				Certificate: [][]byte{derbytes},
+				PrivateKey:  edpriv,
+			},
+		},
+		InsecureSkipVerify: true,
+		MinVersion:         tls.VersionTLS13,
+	}
+}
+
+func (t *tcptls) upgradeListener(c net.Conn) (net.Conn, error) {
+	conn := tls.Server(c, t.config)
+	if err := conn.Handshake(); err != nil {
+		return c, err
+	}
+	return conn, nil
+}
+
+func (t *tcptls) upgradeDialer(c net.Conn) (net.Conn, error) {
+	conn := tls.Client(c, t.config)
+	if err := conn.Handshake(); err != nil {
+		return c, err
+	}
+	return conn, nil
+}