// BuildNameToCertificate parses c.Certificates and builds c.NameToCertificate
// from the CommonName and SubjectAlternateName fields of each of the leaf
// certificates.
func (c *Config) BuildNameToCertificate() {
c.NameToCertificate = make(map[string]*Certificate)
for i := range c.Certificates {
cert := &c.Certificates[i]
x509Cert, err := x509.ParseCertificate(cert.Certificate[0])
if err != nil {
continue
}
if len(x509Cert.Subject.CommonName) > 0 {
c.NameToCertificate[x509Cert.Subject.CommonName] = cert
}
for _, san := range x509Cert.DNSNames {
c.NameToCertificate[san] = cert
}
}
}
func ExampleCertificate_Verify() {
// Verifying with a custom list of root certificates.
const rootPEM = `
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`
const certPEM = `
-----BEGIN CERTIFICATE-----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==
-----END CERTIFICATE-----`
// First, create the set of root certificates. For this example we only
// have one. It's also possible to omit this in order to use the
// default root set of the current operating system.
roots := x509.NewCertPool()
ok := roots.AppendCertsFromPEM([]byte(rootPEM))
if !ok {
panic("failed to parse root certificate")
}
block, _ := pem.Decode([]byte(certPEM))
if block == nil {
panic("failed to parse certificate PEM")
}
cert, err := x509.ParseCertificate(block.Bytes)
if err != nil {
panic("failed to parse certificate: " + err.Error())
}
opts := x509.VerifyOptions{
DNSName: "mail.google.com",
Roots: roots,
}
if _, err := cert.Verify(opts); err != nil {
panic("failed to verify certificate: " + err.Error())
}
}
// X509KeyPair parses a public/private key pair from a pair of
// PEM encoded data.
func X509KeyPair(certPEMBlock, keyPEMBlock []byte) (cert Certificate, err error) {
var certDERBlock *pem.Block
for {
certDERBlock, certPEMBlock = pem.Decode(certPEMBlock)
if certDERBlock == nil {
break
}
if certDERBlock.Type == "CERTIFICATE" {
cert.Certificate = append(cert.Certificate, certDERBlock.Bytes)
}
}
if len(cert.Certificate) == 0 {
err = errors.New("crypto/tls: failed to parse certificate PEM data")
return
}
var keyDERBlock *pem.Block
for {
keyDERBlock, keyPEMBlock = pem.Decode(keyPEMBlock)
if keyDERBlock == nil {
err = errors.New("crypto/tls: failed to parse key PEM data")
return
}
if keyDERBlock.Type == "PRIVATE KEY" || strings.HasSuffix(keyDERBlock.Type, " PRIVATE KEY") {
break
}
}
cert.PrivateKey, err = parsePrivateKey(keyDERBlock.Bytes)
if err != nil {
return
}
// We don't need to parse the public key for TLS, but we so do anyway
// to check that it looks sane and matches the private key.
x509Cert, err := x509.ParseCertificate(cert.Certificate[0])
if err != nil {
return
}
switch pub := x509Cert.PublicKey.(type) {
case *rsa.PublicKey:
priv, ok := cert.PrivateKey.(*rsa.PrivateKey)
if !ok {
err = errors.New("crypto/tls: private key type does not match public key type")
return
}
if pub.N.Cmp(priv.N) != 0 {
err = errors.New("crypto/tls: private key does not match public key")
return
}
case *ecdsa.PublicKey:
priv, ok := cert.PrivateKey.(*ecdsa.PrivateKey)
if !ok {
err = errors.New("crypto/tls: private key type does not match public key type")
return
}
if pub.X.Cmp(priv.X) != 0 || pub.Y.Cmp(priv.Y) != 0 {
err = errors.New("crypto/tls: private key does not match public key")
return
}
default:
err = errors.New("crypto/tls: unknown public key algorithm")
return
}
return
}
// processCertsFromClient takes a chain of client certificates either from a
// Certificates message or from a sessionState and verifies them. It returns
// the public key of the leaf certificate.
func (hs *serverHandshakeState) processCertsFromClient(certificates [][]byte) (crypto.PublicKey, error) {
c := hs.c
hs.certsFromClient = certificates
certs := make([]*x509.Certificate, len(certificates))
var err error
for i, asn1Data := range certificates {
if certs[i], err = x509.ParseCertificate(asn1Data); err != nil {
c.sendAlert(alertBadCertificate)
return nil, errors.New("tls: failed to parse client certificate: " + err.Error())
}
}
if c.config.ClientAuth >= VerifyClientCertIfGiven && len(certs) > 0 {
opts := x509.VerifyOptions{
Roots: c.config.ClientCAs,
CurrentTime: c.config.time(),
Intermediates: x509.NewCertPool(),
KeyUsages: []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth},
}
for _, cert := range certs[1:] {
opts.Intermediates.AddCert(cert)
}
chains, err := certs[0].Verify(opts)
if err != nil {
c.sendAlert(alertBadCertificate)
return nil, errors.New("tls: failed to verify client's certificate: " + err.Error())
}
ok := false
for _, ku := range certs[0].ExtKeyUsage {
if ku == x509.ExtKeyUsageClientAuth {
ok = true
break
}
}
if !ok {
c.sendAlert(alertHandshakeFailure)
return nil, errors.New("tls: client's certificate's extended key usage doesn't permit it to be used for client authentication")
}
c.verifiedChains = chains
}
if len(certs) > 0 {
var pub crypto.PublicKey
switch key := certs[0].PublicKey.(type) {
case *ecdsa.PublicKey, *rsa.PublicKey:
pub = key
default:
c.sendAlert(alertUnsupportedCertificate)
return nil, fmt.Errorf("tls: client's certificate contains an unsupported public key of type %T", certs[0].PublicKey)
}
c.peerCertificates = certs
return pub, nil
}
return nil, nil
}