constellation/internal/watcher/validator.go
Otto Bittner 8f21972aec
attestation: add awsSEVSNP as new variant (#1900)
* variant: move into internal/attestation
* attesation: move aws attesation into subfolder nitrotpm
* config: add aws-sev-snp variant
* cli: add tf option to enable AWS SNP

For now the implementations in aws/nitrotpm and aws/snp
are identical. They both contain the aws/nitrotpm impl.
A separate commit will add the actual attestation logic.
2023-06-09 15:41:02 +02:00

87 lines
2.2 KiB
Go

/*
Copyright (c) Edgeless Systems GmbH
SPDX-License-Identifier: AGPL-3.0-only
*/
package watcher
import (
"context"
"encoding/asn1"
"fmt"
"path/filepath"
"sync"
"github.com/edgelesssys/constellation/v2/internal/atls"
"github.com/edgelesssys/constellation/v2/internal/attestation/choose"
"github.com/edgelesssys/constellation/v2/internal/attestation/variant"
"github.com/edgelesssys/constellation/v2/internal/config"
"github.com/edgelesssys/constellation/v2/internal/constants"
"github.com/edgelesssys/constellation/v2/internal/file"
"github.com/edgelesssys/constellation/v2/internal/logger"
)
// Updatable implements an updatable atls.Validator.
type Updatable struct {
log *logger.Logger
mux sync.Mutex
fileHandler file.Handler
variant variant.Variant
atls.Validator
}
// NewValidator initializes a new updatable validator.
func NewValidator(log *logger.Logger, variant variant.Variant, fileHandler file.Handler) (*Updatable, error) {
u := &Updatable{
log: log,
fileHandler: fileHandler,
variant: variant,
}
if err := u.Update(); err != nil {
return nil, err
}
return u, nil
}
// Validate calls the validators Validate method, and prevents any updates during the call.
func (u *Updatable) Validate(ctx context.Context, attDoc []byte, nonce []byte) ([]byte, error) {
u.mux.Lock()
defer u.mux.Unlock()
return u.Validator.Validate(ctx, attDoc, nonce)
}
// OID returns the validators Object Identifier.
func (u *Updatable) OID() asn1.ObjectIdentifier {
u.mux.Lock()
defer u.mux.Unlock()
return u.Validator.OID()
}
// Update switches out the underlying validator.
func (u *Updatable) Update() error {
u.mux.Lock()
defer u.mux.Unlock()
u.log.Infof("Updating expected measurements")
data, err := u.fileHandler.Read(filepath.Join(constants.ServiceBasePath, constants.AttestationConfigFilename))
if err != nil {
return err
}
cfg, err := config.UnmarshalAttestationConfig(data, u.variant)
if err != nil {
return fmt.Errorf("unmarshaling config: %w", err)
}
u.log.Debugf("New expected measurements: %+v", cfg.GetMeasurements())
validator, err := choose.Validator(cfg, u.log)
if err != nil {
return fmt.Errorf("updating validator: %w", err)
}
u.Validator = validator
return nil
}