smallstep-certificates/authority/tls.go
max furman 1951669e13 wip
2020-06-23 11:10:45 -07:00

363 lines
13 KiB
Go

package authority
import (
"context"
"crypto/tls"
"crypto/x509"
"encoding/asn1"
"encoding/base64"
"encoding/pem"
"net/http"
"strings"
"time"
"github.com/pkg/errors"
"github.com/smallstep/certificates/authority/provisioner"
"github.com/smallstep/certificates/db"
"github.com/smallstep/certificates/errs"
"github.com/smallstep/cli/crypto/pemutil"
"github.com/smallstep/cli/crypto/tlsutil"
"github.com/smallstep/cli/crypto/x509util"
"github.com/smallstep/cli/jose"
)
// 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, error) {
var (
opts = []interface{}{errs.WithKeyVal("csr", csr), errs.WithKeyVal("signOptions", signOpts)}
mods = []x509util.WithOption{withDefaultASN1DN(a.config.AuthorityConfig.Template)}
certValidators = []provisioner.CertificateValidator{}
forcedModifiers = []provisioner.CertificateEnforcer{}
)
// Set backdate with the configured value
signOpts.Backdate = a.config.AuthorityConfig.Backdate.Duration
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, errs.Wrap(http.StatusUnauthorized, err, "authority.Sign", opts...)
}
case provisioner.ProfileModifier:
mods = append(mods, k.Option(signOpts))
case provisioner.CertificateEnforcer:
forcedModifiers = append(forcedModifiers, k)
default:
return nil, errs.InternalServer("authority.Sign; invalid extra option type %T", append([]interface{}{k}, opts...)...)
}
}
if err := csr.CheckSignature(); err != nil {
return nil, errs.Wrap(http.StatusBadRequest, err, "authority.Sign; invalid certificate request", opts...)
}
leaf, err := x509util.NewLeafProfileWithCSR(csr, a.x509Issuer, a.x509Signer, mods...)
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err, "authority.Sign", opts...)
}
// Certificate validation
for _, v := range certValidators {
if err := v.Valid(leaf.Subject(), signOpts); err != nil {
return nil, errs.Wrap(http.StatusUnauthorized, err, "authority.Sign", opts...)
}
}
// Certificate modifiers after validation
for _, m := range append(forcedModifiers, provisioner.ExtraExtensionsEnforcer{}) {
if err := m.Enforce(leaf.Subject()); err != nil {
return nil, errs.Wrap(http.StatusUnauthorized, err, "authority.Sign", opts...)
}
}
crtBytes, err := leaf.CreateCertificate()
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err,
"authority.Sign; error creating new leaf certificate", opts...)
}
serverCert, err := x509.ParseCertificate(crtBytes)
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err,
"authority.Sign; error parsing new leaf certificate", opts...)
}
if err = a.db.StoreCertificate(serverCert); err != nil {
if err != db.ErrNotImplemented {
return nil, errs.Wrap(http.StatusInternalServerError, err,
"authority.Sign; error storing certificate in db", opts...)
}
}
return []*x509.Certificate{serverCert, a.x509Issuer}, 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, error) {
opts := []interface{}{errs.WithKeyVal("serialNumber", oldCert.SerialNumber.String())}
// Check step provisioner extensions
if err := a.authorizeRenew(oldCert); err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err, "authority.Renew", opts...)
}
// Durations
backdate := a.config.AuthorityConfig.Backdate.Duration
duration := oldCert.NotAfter.Sub(oldCert.NotBefore)
now := time.Now().UTC()
newCert := &x509.Certificate{
PublicKey: oldCert.PublicKey,
Issuer: a.x509Issuer.Subject,
Subject: oldCert.Subject,
NotBefore: now.Add(-1 * backdate),
NotAfter: now.Add(duration - backdate),
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,
PermittedDNSDomainsCritical: oldCert.PermittedDNSDomainsCritical,
PermittedEmailAddresses: oldCert.PermittedEmailAddresses,
DNSNames: oldCert.DNSNames,
EmailAddresses: oldCert.EmailAddresses,
IPAddresses: oldCert.IPAddresses,
URIs: oldCert.URIs,
PermittedDNSDomains: oldCert.PermittedDNSDomains,
ExcludedDNSDomains: oldCert.ExcludedDNSDomains,
PermittedIPRanges: oldCert.PermittedIPRanges,
ExcludedIPRanges: oldCert.ExcludedIPRanges,
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, a.x509Issuer, a.x509Signer)
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err, "authority.Renew", opts...)
}
crtBytes, err := leaf.CreateCertificate()
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err,
"authority.Renew; error renewing certificate from existing server certificate", opts...)
}
serverCert, err := x509.ParseCertificate(crtBytes)
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err,
"authority.Renew; error parsing new server certificate", opts...)
}
if err = a.db.StoreCertificate(serverCert); err != nil {
if err != db.ErrNotImplemented {
return nil, errs.Wrap(http.StatusInternalServerError, err, "authority.Renew; error storing certificate in db", opts...)
}
}
return []*x509.Certificate{serverCert, a.x509Issuer}, nil
}
// RevokeOptions are the options for the Revoke API.
type RevokeOptions struct {
Serial string
Reason string
ReasonCode int
PassiveOnly bool
MTLS bool
Crt *x509.Certificate
OTT string
}
// Revoke revokes a certificate.
//
// NOTE: Only supports passive revocation - prevent existing certificates from
// being renewed.
//
// TODO: Add OCSP and CRL support.
func (a *Authority) Revoke(ctx context.Context, revokeOpts *RevokeOptions) error {
opts := []interface{}{
errs.WithKeyVal("serialNumber", revokeOpts.Serial),
errs.WithKeyVal("reasonCode", revokeOpts.ReasonCode),
errs.WithKeyVal("reason", revokeOpts.Reason),
errs.WithKeyVal("passiveOnly", revokeOpts.PassiveOnly),
errs.WithKeyVal("MTLS", revokeOpts.MTLS),
errs.WithKeyVal("context", string(provisioner.MethodFromContext(ctx))),
}
if revokeOpts.MTLS {
opts = append(opts, errs.WithKeyVal("certificate", base64.StdEncoding.EncodeToString(revokeOpts.Crt.Raw)))
} else {
opts = append(opts, errs.WithKeyVal("token", revokeOpts.OTT))
}
rci := &db.RevokedCertificateInfo{
Serial: revokeOpts.Serial,
ReasonCode: revokeOpts.ReasonCode,
Reason: revokeOpts.Reason,
MTLS: revokeOpts.MTLS,
RevokedAt: time.Now().UTC(),
}
var (
p provisioner.Interface
err error
)
// If not mTLS then get the TokenID of the token.
if !revokeOpts.MTLS {
token, err := jose.ParseSigned(revokeOpts.OTT)
if err != nil {
return errs.Wrap(http.StatusUnauthorized, err,
"authority.Revoke; error parsing token", opts...)
}
// Get claims w/out verification.
var claims Claims
if err = token.UnsafeClaimsWithoutVerification(&claims); err != nil {
return errs.Wrap(http.StatusUnauthorized, err, "authority.Revoke", opts...)
}
// This method will also validate the audiences for JWK provisioners.
var ok bool
p, ok = a.provisioners.LoadByToken(token, &claims.Claims)
if !ok {
return errs.InternalServer("authority.Revoke; provisioner not found", opts...)
}
rci.TokenID, err = p.GetTokenID(revokeOpts.OTT)
if err != nil {
return errs.Wrap(http.StatusInternalServerError, err,
"authority.Revoke; could not get ID for token")
}
opts = append(opts, errs.WithKeyVal("tokenID", rci.TokenID))
} else {
// Load the Certificate provisioner if one exists.
p, err = a.LoadProvisionerByCertificate(revokeOpts.Crt)
if err != nil {
return errs.Wrap(http.StatusUnauthorized, err,
"authority.Revoke: unable to load certificate provisioner", opts...)
}
}
rci.ProvisionerID = p.GetID()
opts = append(opts, errs.WithKeyVal("provisionerID", rci.ProvisionerID))
if provisioner.MethodFromContext(ctx) == provisioner.SSHRevokeMethod {
err = a.db.RevokeSSH(rci)
} else { // default to revoke x509
err = a.db.Revoke(rci)
}
switch err {
case nil:
return nil
case db.ErrNotImplemented:
return errs.NotImplemented("authority.Revoke; no persistence layer configured", opts...)
case db.ErrAlreadyExists:
return errs.BadRequest("authority.Revoke; certificate with serial "+
"number %s has already been revoked", append([]interface{}{rci.Serial}, opts...)...)
default:
return errs.Wrap(http.StatusInternalServerError, err, "authority.Revoke", opts...)
}
}
// 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.x509Issuer, a.x509Signer,
x509util.WithHosts(strings.Join(a.config.DNSNames, ",")))
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err, "authority.GetTLSCertificate")
}
crtBytes, err := profile.CreateCertificate()
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err, "authority.GetTLSCertificate")
}
keyPEM, err := pemutil.Serialize(profile.SubjectPrivateKey())
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err, "authority.GetTLSCertificate")
}
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.x509Issuer)
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err, "authority.GetTLSCertificate")
}
tlsCrt, err := tls.X509KeyPair(append(crtPEM,
pem.EncodeToMemory(intermediatePEM)...),
pem.EncodeToMemory(keyPEM))
if err != nil {
return nil, errs.Wrap(http.StatusInternalServerError, err,
"authority.GetTLSCertificate; 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, errs.Wrap(http.StatusInternalServerError, err,
"authority.GetTLSCertificate; error parsing tls certificate")
}
tlsCrt.Leaf = leaf
return &tlsCrt, nil
}