constellation/internal/attestation/azure/imds.go
Otto Bittner 7c5556864b AB#2333: Add AMD SNP-based attestation
Currently only available on Azure CVMs.

* Get the public attestation key from the TPM.
* Get the snp report from the TPM.
* Get the VCEK and ASK certificate from the metadata api.
* Verify VCEK using hardcoded root key (ARK)
* Verify SNP report using VCEK
* Verify HCLAkPub using SNP report by comparing
AK with runtimeData
* Extend unittest

Co-authored-by: Thomas Tendyck <51411342+thomasten@users.noreply.github.com>
Co-authored-by: Daniel Weiße <dw@edgeless.systems>
2022-08-29 16:29:33 +02:00

44 lines
899 B
Go

package azure
import (
"context"
"encoding/json"
"net/http"
)
// Modified version of bootstrapper/cloudprovider/azure/imds.go
const (
imdsVcekURL = "http://169.254.169.254/metadata/THIM/amd/certification"
)
type imdsClient struct {
client *http.Client
}
// Retrieve retrieves instance metadata from the azure imds API.
func (c imdsClient) getVcek(ctx context.Context) (vcekResponse, error) {
req, err := http.NewRequestWithContext(ctx, http.MethodGet, imdsVcekURL, http.NoBody)
if err != nil {
return vcekResponse{}, err
}
req.Header.Add("Metadata", "True")
resp, err := c.client.Do(req)
if err != nil {
return vcekResponse{}, err
}
defer resp.Body.Close()
var res vcekResponse
if err := json.NewDecoder(resp.Body).Decode(&res); err != nil {
return vcekResponse{}, err
}
return res, nil
}
type vcekResponse struct {
VcekCert string
CertificateChain string
}