certificates/authority/tls.go
2019-03-20 18:11:45 -07:00

242 lines
8.5 KiB
Go

package authority
import (
"crypto/tls"
"crypto/x509"
"encoding/asn1"
"encoding/pem"
"net/http"
"strings"
"time"
"github.com/pkg/errors"
"github.com/smallstep/certificates/authority/provisioner"
"github.com/smallstep/cli/crypto/pemutil"
"github.com/smallstep/cli/crypto/tlsutil"
"github.com/smallstep/cli/crypto/x509util"
)
// GetTLSOptions returns the tls options configured.
func (a *Authority) GetTLSOptions() *tlsutil.TLSOptions {
return a.config.TLS
}
var oidAuthorityKeyIdentifier = asn1.ObjectIdentifier{2, 5, 29, 35}
func withDefaultASN1DN(def *x509util.ASN1DN) x509util.WithOption {
return func(p x509util.Profile) error {
if def == nil {
return errors.New("default ASN1DN template cannot be nil")
}
crt := p.Subject()
if len(crt.Subject.Country) == 0 && def.Country != "" {
crt.Subject.Country = append(crt.Subject.Country, def.Country)
}
if len(crt.Subject.Organization) == 0 && def.Organization != "" {
crt.Subject.Organization = append(crt.Subject.Organization, def.Organization)
}
if len(crt.Subject.OrganizationalUnit) == 0 && def.OrganizationalUnit != "" {
crt.Subject.OrganizationalUnit = append(crt.Subject.OrganizationalUnit, def.OrganizationalUnit)
}
if len(crt.Subject.Locality) == 0 && def.Locality != "" {
crt.Subject.Locality = append(crt.Subject.Locality, def.Locality)
}
if len(crt.Subject.Province) == 0 && def.Province != "" {
crt.Subject.Province = append(crt.Subject.Province, def.Province)
}
if len(crt.Subject.StreetAddress) == 0 && def.StreetAddress != "" {
crt.Subject.StreetAddress = append(crt.Subject.StreetAddress, def.StreetAddress)
}
return nil
}
}
// Sign creates a signed certificate from a certificate signing request.
func (a *Authority) Sign(csr *x509.CertificateRequest, signOpts provisioner.Options, extraOpts ...provisioner.SignOption) (*x509.Certificate, *x509.Certificate, error) {
var (
errContext = context{"csr": csr, "signOptions": signOpts}
mods = []x509util.WithOption{withDefaultASN1DN(a.config.AuthorityConfig.Template)}
certValidators = []provisioner.CertificateValidator{}
issIdentity = a.intermediateIdentity
)
for _, op := range extraOpts {
switch k := op.(type) {
case provisioner.CertificateValidator:
certValidators = append(certValidators, k)
case provisioner.CertificateRequestValidator:
if err := k.Valid(csr); err != nil {
return nil, nil, &apiError{errors.Wrap(err, "sign"), http.StatusUnauthorized, errContext}
}
case provisioner.ProfileModifier:
mods = append(mods, k.Option(signOpts))
default:
return nil, nil, &apiError{errors.Errorf("sign: invalid extra option type %T", k),
http.StatusInternalServerError, errContext}
}
}
if err := csr.CheckSignature(); err != nil {
return nil, nil, &apiError{errors.Wrap(err, "sign: invalid certificate request"),
http.StatusBadRequest, errContext}
}
leaf, err := x509util.NewLeafProfileWithCSR(csr, issIdentity.Crt, issIdentity.Key, mods...)
if err != nil {
return nil, nil, &apiError{errors.Wrapf(err, "sign"), http.StatusInternalServerError, errContext}
}
for _, v := range certValidators {
if err := v.Valid(leaf.Subject()); err != nil {
return nil, nil, &apiError{errors.Wrap(err, "sign"), http.StatusUnauthorized, errContext}
}
}
crtBytes, err := leaf.CreateCertificate()
if err != nil {
return nil, nil, &apiError{errors.Wrap(err, "sign: error creating new leaf certificate"),
http.StatusInternalServerError, errContext}
}
serverCert, err := x509.ParseCertificate(crtBytes)
if err != nil {
return nil, nil, &apiError{errors.Wrap(err, "sign: error parsing new leaf certificate"),
http.StatusInternalServerError, errContext}
}
caCert, err := x509.ParseCertificate(issIdentity.Crt.Raw)
if err != nil {
return nil, nil, &apiError{errors.Wrap(err, "sign: error parsing intermediate certificate"),
http.StatusInternalServerError, errContext}
}
return serverCert, caCert, nil
}
// Renew creates a new Certificate identical to the old certificate, except
// with a validity window that begins 'now'.
func (a *Authority) Renew(oldCert *x509.Certificate) (*x509.Certificate, *x509.Certificate, error) {
// Check step provisioner extensions
if err := a.authorizeRenewal(oldCert); err != nil {
return nil, nil, err
}
// Issuer
issIdentity := a.intermediateIdentity
now := time.Now().UTC()
duration := oldCert.NotAfter.Sub(oldCert.NotBefore)
newCert := &x509.Certificate{
PublicKey: oldCert.PublicKey,
Issuer: issIdentity.Crt.Subject,
Subject: oldCert.Subject,
NotBefore: now,
NotAfter: now.Add(duration),
KeyUsage: oldCert.KeyUsage,
UnhandledCriticalExtensions: oldCert.UnhandledCriticalExtensions,
ExtKeyUsage: oldCert.ExtKeyUsage,
UnknownExtKeyUsage: oldCert.UnknownExtKeyUsage,
BasicConstraintsValid: oldCert.BasicConstraintsValid,
IsCA: oldCert.IsCA,
MaxPathLen: oldCert.MaxPathLen,
MaxPathLenZero: oldCert.MaxPathLenZero,
OCSPServer: oldCert.OCSPServer,
IssuingCertificateURL: oldCert.IssuingCertificateURL,
DNSNames: oldCert.DNSNames,
EmailAddresses: oldCert.EmailAddresses,
IPAddresses: oldCert.IPAddresses,
URIs: oldCert.URIs,
PermittedDNSDomainsCritical: oldCert.PermittedDNSDomainsCritical,
PermittedDNSDomains: oldCert.PermittedDNSDomains,
ExcludedDNSDomains: oldCert.ExcludedDNSDomains,
PermittedIPRanges: oldCert.PermittedIPRanges,
ExcludedIPRanges: oldCert.ExcludedIPRanges,
PermittedEmailAddresses: oldCert.PermittedEmailAddresses,
ExcludedEmailAddresses: oldCert.ExcludedEmailAddresses,
PermittedURIDomains: oldCert.PermittedURIDomains,
ExcludedURIDomains: oldCert.ExcludedURIDomains,
CRLDistributionPoints: oldCert.CRLDistributionPoints,
PolicyIdentifiers: oldCert.PolicyIdentifiers,
}
// Copy all extensions except for Authority Key Identifier. This one might
// be different if we rotate the intermediate certificate and it will cause
// a TLS bad certificate error.
for _, ext := range oldCert.Extensions {
if !ext.Id.Equal(oidAuthorityKeyIdentifier) {
newCert.ExtraExtensions = append(newCert.ExtraExtensions, ext)
}
}
leaf, err := x509util.NewLeafProfileWithTemplate(newCert,
issIdentity.Crt, issIdentity.Key)
if err != nil {
return nil, nil, &apiError{err, http.StatusInternalServerError, context{}}
}
crtBytes, err := leaf.CreateCertificate()
if err != nil {
return nil, nil, &apiError{errors.Wrap(err, "error renewing certificate from existing server certificate"),
http.StatusInternalServerError, context{}}
}
serverCert, err := x509.ParseCertificate(crtBytes)
if err != nil {
return nil, nil, &apiError{errors.Wrap(err, "error parsing new server certificate"),
http.StatusInternalServerError, context{}}
}
caCert, err := x509.ParseCertificate(issIdentity.Crt.Raw)
if err != nil {
return nil, nil, &apiError{errors.Wrap(err, "error parsing intermediate certificate"),
http.StatusInternalServerError, context{}}
}
return serverCert, caCert, nil
}
// GetTLSCertificate creates a new leaf certificate to be used by the CA HTTPS server.
func (a *Authority) GetTLSCertificate() (*tls.Certificate, error) {
profile, err := x509util.NewLeafProfile("Step Online CA",
a.intermediateIdentity.Crt, a.intermediateIdentity.Key,
x509util.WithHosts(strings.Join(a.config.DNSNames, ",")))
if err != nil {
return nil, err
}
crtBytes, err := profile.CreateCertificate()
if err != nil {
return nil, err
}
keyPEM, err := pemutil.Serialize(profile.SubjectPrivateKey())
if err != nil {
return nil, err
}
crtPEM := pem.EncodeToMemory(&pem.Block{
Type: "CERTIFICATE",
Bytes: crtBytes,
})
// Load the x509 key pair (combining server and intermediate blocks)
// to a tls.Certificate.
intermediatePEM, err := pemutil.Serialize(a.intermediateIdentity.Crt)
if err != nil {
return nil, err
}
tlsCrt, err := tls.X509KeyPair(append(crtPEM,
pem.EncodeToMemory(intermediatePEM)...),
pem.EncodeToMemory(keyPEM))
if err != nil {
return nil, errors.Wrap(err, "error creating tls certificate")
}
// Get the 'leaf' certificate and set the attribute accordingly.
leaf, err := x509.ParseCertificate(tlsCrt.Certificate[0])
if err != nil {
return nil, errors.Wrap(err, "error parsing tls certificate")
}
tlsCrt.Leaf = leaf
return &tlsCrt, nil
}