mirror of
https://github.com/edgelesssys/constellation.git
synced 2024-10-01 01:36:09 -04:00
bb76a4e4c8
* refactor measurements to use consistent types and less byte pushing * refactor: only rely on a single multierr dependency * extend config creation with envar support * document changes Signed-off-by: Fabian Kammel <fk@edgeless.systems>
113 lines
4.9 KiB
Go
113 lines
4.9 KiB
Go
/*
|
|
Copyright (c) Edgeless Systems GmbH
|
|
|
|
SPDX-License-Identifier: AGPL-3.0-only
|
|
*/
|
|
|
|
package trustedlaunch
|
|
|
|
import (
|
|
"crypto"
|
|
"crypto/rsa"
|
|
"crypto/x509"
|
|
"encoding/json"
|
|
"errors"
|
|
"fmt"
|
|
|
|
"github.com/edgelesssys/constellation/v2/internal/attestation/measurements"
|
|
"github.com/edgelesssys/constellation/v2/internal/attestation/vtpm"
|
|
certutil "github.com/edgelesssys/constellation/v2/internal/crypto"
|
|
"github.com/edgelesssys/constellation/v2/internal/oid"
|
|
"github.com/google/go-tpm/tpm2"
|
|
)
|
|
|
|
// ameRoot is the AME root CA certificate used to sign Azure's AME Infra CA certificates.
|
|
// The certificate can be found at http://crl.microsoft.com/pkiinfra/certs/AMERoot_ameroot.crt.
|
|
var ameRoot = mustParseX509("-----BEGIN CERTIFICATE-----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\nyTra6P0Kvo6xz4KaVm8F7VDzUP+heAAhPAs=\n-----END CERTIFICATE-----\n")
|
|
|
|
// Validator for Azure trusted launch VM attestation.
|
|
type Validator struct {
|
|
oid.AzureTrustedLaunch
|
|
*vtpm.Validator
|
|
roots *x509.CertPool
|
|
}
|
|
|
|
// NewValidator initializes a new Azure validator with the provided PCR values.
|
|
func NewValidator(pcrs measurements.M, enforcedPCRs []uint32, log vtpm.AttestationLogger) *Validator {
|
|
rootPool := x509.NewCertPool()
|
|
rootPool.AddCert(ameRoot)
|
|
v := &Validator{roots: rootPool}
|
|
v.Validator = vtpm.NewValidator(
|
|
pcrs,
|
|
enforcedPCRs,
|
|
v.verifyAttestationKey,
|
|
validateVM,
|
|
vtpm.VerifyPKCS1v15,
|
|
log,
|
|
)
|
|
return v
|
|
}
|
|
|
|
// verifyAttestationKey establishes trust in an attestation key.
|
|
// It does so by verifying the certificate chain of the attestation key certificate.
|
|
func (v *Validator) verifyAttestationKey(akPub, instanceInfo []byte) (crypto.PublicKey, error) {
|
|
pubArea, err := tpm2.DecodePublic(akPub)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("decoding attestation key public area: %w", err)
|
|
}
|
|
|
|
var akSigner akSigner
|
|
if err := json.Unmarshal(instanceInfo, &akSigner); err != nil {
|
|
return nil, fmt.Errorf("unmarshaling attestation key signer info: %w", err)
|
|
}
|
|
|
|
akCert, err := x509.ParseCertificate(akSigner.AkCert)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("parsing attestation key certificate: %w", err)
|
|
}
|
|
akCertCA, err := x509.ParseCertificate(akSigner.CA)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("parsing attestation key CA certificate: %w", err)
|
|
}
|
|
|
|
intermediates := x509.NewCertPool()
|
|
intermediates.AddCert(akCertCA)
|
|
|
|
if _, err := akCert.Verify(x509.VerifyOptions{
|
|
Roots: v.roots,
|
|
Intermediates: intermediates,
|
|
KeyUsages: []x509.ExtKeyUsage{x509.ExtKeyUsageAny},
|
|
}); err != nil {
|
|
return nil, fmt.Errorf("verifying attestation key certificate: %w", err)
|
|
}
|
|
|
|
pubKey, err := pubArea.Key()
|
|
if err != nil {
|
|
return nil, fmt.Errorf("getting public key: %w", err)
|
|
}
|
|
|
|
pubKeyRSA, ok := pubKey.(*rsa.PublicKey)
|
|
if !ok {
|
|
return nil, errors.New("attestation key is not an RSA key")
|
|
}
|
|
|
|
if !pubKeyRSA.Equal(akCert.PublicKey) {
|
|
return nil, errors.New("certificate public key does not match attestation key")
|
|
}
|
|
|
|
return pubKeyRSA, nil
|
|
}
|
|
|
|
// validateVM returns nil.
|
|
func validateVM(attestation vtpm.AttestationDocument) error {
|
|
return nil
|
|
}
|
|
|
|
func mustParseX509(pem string) *x509.Certificate {
|
|
cert, err := certutil.PemToX509Cert([]byte(pem))
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
return cert
|
|
}
|