package server import ( "crypto/ecdsa" "crypto/elliptic" "crypto/rand" "crypto/tls" "crypto/x509" "crypto/x509/pkix" "encoding/pem" "math/big" "net" "time" "github.com/ethereum/go-ethereum/log" ) var globalMediaCertificate *tls.Certificate = nil var globalMediaPem string func makeRandomSerialNumber() (*big.Int, error) { serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128) return rand.Int(rand.Reader, serialNumberLimit) } func GenerateX509Cert(sn *big.Int, from, to time.Time, IPAddresses []net.IP, DNSNames []string) *x509.Certificate { return &x509.Certificate{ SerialNumber: sn, Subject: pkix.Name{Organization: []string{"Self-signed cert"}}, NotBefore: from, NotAfter: to, KeyUsage: x509.KeyUsageDigitalSignature | x509.KeyUsageCertSign, ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth}, BasicConstraintsValid: true, IsCA: true, IPAddresses: IPAddresses, DNSNames: DNSNames, } } func GenerateX509PEMs(cert *x509.Certificate, key *ecdsa.PrivateKey) (certPem, keyPem []byte, err error) { derBytes, err := x509.CreateCertificate(rand.Reader, cert, cert, &key.PublicKey, key) if err != nil { return } certPem = pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: derBytes}) privBytes, err := x509.MarshalPKCS8PrivateKey(key) if err != nil { return } keyPem = pem.EncodeToMemory(&pem.Block{Type: "PRIVATE KEY", Bytes: privBytes}) return } func GenerateTLSCert(notBefore, notAfter time.Time, IPAddresses []net.IP, DNSNames []string) (*tls.Certificate, []byte, error) { priv, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader) if err != nil { return nil, nil, err } sn, err := makeRandomSerialNumber() if err != nil { return nil, nil, err } cert := GenerateX509Cert(sn, notBefore, notAfter, IPAddresses, DNSNames) certPem, keyPem, err := GenerateX509PEMs(cert, priv) if err != nil { return nil, nil, err } finalCert, err := tls.X509KeyPair(certPem, keyPem) return &finalCert, certPem, err } func generateMediaTLSCert() error { if globalMediaCertificate != nil { return nil } now := time.Now() notBefore := now.Add(-365 * 24 * time.Hour * 100) notAfter := now.Add(365 * 24 * time.Hour * 100) log.Debug("generate media cert", "system time", time.Now().String(), "cert notBefore", notBefore.String(), "cert notAfter", notAfter.String()) finalCert, certPem, err := GenerateTLSCert(notBefore, notAfter, []net.IP{}, []string{Localhost}) if err != nil { return err } globalMediaCertificate = finalCert globalMediaPem = string(certPem) return nil } func PublicMediaTLSCert() (string, error) { err := generateMediaTLSCert() if err != nil { return "", err } return globalMediaPem, nil } // ToECDSA takes a []byte of D and uses it to create an ecdsa.PublicKey on the elliptic.P256 curve // this function is basically a P256 curve version of eth-node/crypto.ToECDSA without all the nice validation func ToECDSA(d []byte) *ecdsa.PrivateKey { k := new(ecdsa.PrivateKey) k.D = new(big.Int).SetBytes(d) k.PublicKey.Curve = elliptic.P256() k.PublicKey.X, k.PublicKey.Y = k.PublicKey.Curve.ScalarBaseMult(d) return k }