Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Fix issues with cert generation #259

Merged
merged 1 commit into from
Nov 7, 2023
Merged

Fix issues with cert generation #259

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 1 addition & 6 deletions pkg/dtls/listener.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -256,10 +256,5 @@ func (l *Listener) getCertificateFromClientHello(clientHello *dtls.ClientHelloIn
}

func randomCertificate() (*tls.Certificate, error) {
seedBytes := []byte{}
_, err := rand.Read(seedBytes)
if err != nil {
return nil, err
}
return newCertificate(seedBytes)
return newCertificate(rand.Reader)
}
35 changes: 17 additions & 18 deletions pkg/dtls/seedtocert.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -22,7 +22,7 @@ import (
)

func clientHelloRandomFromSeed(seed []byte) ([handshake.RandomBytesLength]byte, error) {
randSource := hkdf.New(sha256.New, seed, nil, nil)
randSource := hkdf.New(sha256.New, seed, []byte("clientHelloRandomFromSeed"), nil)
randomBytes := [handshake.RandomBytesLength]byte{}

_, err := io.ReadFull(randSource, randomBytes[:])
Expand All @@ -34,19 +34,17 @@ func clientHelloRandomFromSeed(seed []byte) ([handshake.RandomBytesLength]byte,
}

// getPrivkey creates ECDSA private key used in DTLS Certificates
func getPrivkey(seed []byte) (*ecdsa.PrivateKey, error) {
randSource := hkdf.New(sha256.New, seed, nil, nil)

func getPrivkey(randSource io.Reader) (*ecdsa.PrivateKey, error) {
privkey, err := keygen.ECDSALegacy(elliptic.P256(), randSource)
if err != nil {
return &ecdsa.PrivateKey{}, err
}

return privkey, nil
}

// getX509Tpl creates x509 template for x509 Certificates generation used in DTLS Certificates.
func getX509Tpl(seed []byte) (*x509.Certificate, error) {
randSource := hkdf.New(sha256.New, seed, nil, nil)
func getX509Tpl(randSource io.Reader) (*x509.Certificate, error) {

maxBigInt := new(big.Int)
maxBigInt.Exp(big.NewInt(2), big.NewInt(130), nil).Sub(maxBigInt, big.NewInt(1))
Expand Down Expand Up @@ -86,20 +84,19 @@ func getX509Tpl(seed []byte) (*x509.Certificate, error) {
}, nil
}

func newCertificate(seed []byte) (*tls.Certificate, error) {
privkey, err := getPrivkey(seed)
func newCertificate(randSource io.Reader) (*tls.Certificate, error) {

privkey, err := getPrivkey(randSource)
if err != nil {
return &tls.Certificate{}, err
}

tpl, err := getX509Tpl(seed)
tpl, err := getX509Tpl(randSource)
if err != nil {
return &tls.Certificate{}, err
}

randSource := hkdf.New(sha256.New, seed, nil, nil)

certDER, err := x509.CreateCertificate(randSource, tpl, tpl, privkey.Public(), privkey)
certDER, err := x509.CreateCertificate(rand.Reader, tpl, tpl, privkey.Public(), privkey)
if err != nil {
return &tls.Certificate{}, err
}
Expand All @@ -111,15 +108,17 @@ func newCertificate(seed []byte) (*tls.Certificate, error) {
}

func certsFromSeed(seed []byte) (*tls.Certificate, *tls.Certificate, error) {
clientCert, err := newCertificate(seed)
randSource := hkdf.New(sha256.New, seed, []byte("certsFromSeed"), nil)

clientCert, err := newCertificate(randSource)
if err != nil {
return &tls.Certificate{}, &tls.Certificate{}, fmt.Errorf("error generate cert: %v", err)
}

// serverCert, err := newCertificate(seed)
// if err != nil {
// return &tls.Certificate{}, &tls.Certificate{}, fmt.Errorf("error generate cert: %v", err)
// }
serverCert, err := newCertificate(randSource)
if err != nil {
return &tls.Certificate{}, &tls.Certificate{}, fmt.Errorf("error generate cert: %v", err)
}

return clientCert, clientCert, nil
return clientCert, serverCert, nil
}
Loading