// Bundle takes an X509 certificate (already in the
// Certificate structure), a private key as crypto.Signer in one of the appropriate
// formats (i.e. *rsa.PrivateKey or *ecdsa.PrivateKey, or even a opaque key), using them to
// build a certificate bundle.
func (b *Bundler) Bundle(certs []*x509.Certificate, key crypto.Signer, flavor BundleFlavor) (*Bundle, error) {
log.Infof("bundling certificate for %+v", certs[0].Subject)
if len(certs) == 0 {
return nil, nil
}
// Detect reverse ordering of the cert chain.
if len(certs) > 1 && !partialVerify(certs) {
rcerts := reverse(certs)
if partialVerify(rcerts) {
certs = rcerts
}
}
var ok bool
cert := certs[0]
if key != nil {
switch {
case cert.PublicKeyAlgorithm == x509.RSA:
var rsaPublicKey *rsa.PublicKey
if rsaPublicKey, ok = key.Public().(*rsa.PublicKey); !ok {
return nil, errors.New(errors.PrivateKeyError, errors.KeyMismatch)
}
if cert.PublicKey.(*rsa.PublicKey).N.Cmp(rsaPublicKey.N) != 0 {
return nil, errors.New(errors.PrivateKeyError, errors.KeyMismatch)
}
case cert.PublicKeyAlgorithm == x509.ECDSA:
var ecdsaPublicKey *ecdsa.PublicKey
if ecdsaPublicKey, ok = key.Public().(*ecdsa.PublicKey); !ok {
return nil, errors.New(errors.PrivateKeyError, errors.KeyMismatch)
}
if cert.PublicKey.(*ecdsa.PublicKey).X.Cmp(ecdsaPublicKey.X) != 0 {
return nil, errors.New(errors.PrivateKeyError, errors.KeyMismatch)
}
default:
return nil, errors.New(errors.PrivateKeyError, errors.NotRSAOrECC)
}
} else {
switch {
case cert.PublicKeyAlgorithm == x509.RSA:
case cert.PublicKeyAlgorithm == x509.ECDSA:
default:
return nil, errors.New(errors.PrivateKeyError, errors.NotRSAOrECC)
}
}
if cert.CheckSignatureFrom(cert) == nil {
return nil, errors.New(errors.CertificateError, errors.SelfSigned)
}
bundle := new(Bundle)
bundle.Cert = cert
bundle.Key = key
bundle.Issuer = &cert.Issuer
bundle.Subject = &cert.Subject
bundle.buildHostnames()
// verify and store input intermediates to the intermediate pool.
// Ignore the returned error here, will treat it in the second call.
b.fetchIntermediates(certs)
chains, err := cert.Verify(b.VerifyOptions())
if err != nil {
log.Debugf("verification failed: %v", err)
// If the error was an unknown authority, try to fetch
// the intermediate specified in the AIA and add it to
// the intermediates bundle.
switch err := err.(type) {
case x509.UnknownAuthorityError:
// Do nothing -- have the default case return out.
default:
return nil, errors.Wrap(errors.CertificateError, errors.VerifyFailed, err)
}
log.Debugf("searching for intermediates via AIA issuer")
err = b.fetchIntermediates(certs)
if err != nil {
log.Debugf("search failed: %v", err)
return nil, errors.Wrap(errors.CertificateError, errors.VerifyFailed, err)
}
log.Debugf("verifying new chain")
chains, err = cert.Verify(b.VerifyOptions())
if err != nil {
log.Debugf("failed to verify chain: %v", err)
return nil, errors.Wrap(errors.CertificateError, errors.VerifyFailed, err)
}
log.Debugf("verify ok")
}
var matchingChains [][]*x509.Certificate
switch flavor {
case Optimal:
matchingChains = optimalChains(chains)
case Ubiquitous:
if len(ubiquity.Platforms) == 0 {
log.Warning("No metadata, Ubiquitous falls back to Optimal.")
}
matchingChains = ubiquitousChains(chains)
case Force:
matchingChains = forceChains(certs, chains)
default:
matchingChains = ubiquitousChains(chains)
}
bundle.Chain = matchingChains[0]
// Include at least one intermediate if the leaf has enabled OCSP and is not CA.
if bundle.Cert.OCSPServer != nil && !bundle.Cert.IsCA && len(bundle.Chain) <= 2 {
// No op. Return one intermediate if there is one.
} else {
// do not include the root.
bundle.Chain = bundle.Chain[:len(bundle.Chain)-1]
}
statusCode := int(errors.Success)
var messages []string
// Check if bundle is expiring.
expiringCerts := checkExpiringCerts(bundle.Chain)
bundle.Expires = helpers.ExpiryTime(bundle.Chain)
if len(expiringCerts) > 0 {
statusCode |= errors.BundleExpiringBit
messages = append(messages, expirationWarning(expiringCerts))
}
// Check if bundle contains SHA2 certs.
if ubiquity.ChainHashUbiquity(matchingChains[0]) <= ubiquity.SHA2Ubiquity {
statusCode |= errors.BundleNotUbiquitousBit
messages = append(messages, sha2Warning)
}
// Check if bundle contains ECDSA signatures.
if ubiquity.ChainKeyAlgoUbiquity(matchingChains[0]) <= ubiquity.ECDSA256Ubiquity {
statusCode |= errors.BundleNotUbiquitousBit
messages = append(messages, ecdsaWarning)
}
// Add root store presence info
root := matchingChains[0][len(matchingChains[0])-1]
bundle.Root = root
log.Infof("the anchoring root is %v", root.Subject)
// Check if there is any platform that doesn't trust the chain.
// Also, an warning will be generated if ubiquity.Platforms is nil,
untrusted := ubiquity.UntrustedPlatforms(root)
untrustedMsg := untrustedPlatformsWarning(untrusted)
if len(untrustedMsg) > 0 {
log.Debug("Populate untrusted platform warning.")
statusCode |= errors.BundleNotUbiquitousBit
messages = append(messages, untrustedMsg)
}
// Check if there is any platform that rejects the chain because of SHA1 deprecation.
deprecated := ubiquity.DeprecatedSHA1Platforms(matchingChains[0])
if len(deprecated) > 0 {
log.Debug("Populate SHA1 deprecation warning.")
statusCode |= errors.BundleNotUbiquitousBit
messages = append(messages, deprecateSHA1Warning(deprecated))
}
bundle.Status = &BundleStatus{ExpiringSKIs: getSKIs(bundle.Chain, expiringCerts), Code: statusCode, Messages: messages, Untrusted: untrusted}
bundle.Status.IsRebundled = diff(bundle.Chain, certs)
log.Debugf("bundle complete")
return bundle, nil
}
// CompareChainExpiry ranks chain that lasts longer higher.
func CompareChainExpiry(chain1, chain2 []*x509.Certificate) int {
t1 := helpers.ExpiryTime(chain1)
t2 := helpers.ExpiryTime(chain2)
return compareTime(t1, t2)
}