symmetric.go 1.4 KB

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  1. package jwk
  2. import (
  3. "crypto"
  4. "fmt"
  5. "github.com/lestrrat-go/blackmagic"
  6. "github.com/lestrrat-go/jwx/internal/base64"
  7. "github.com/pkg/errors"
  8. )
  9. func (k *symmetricKey) FromRaw(rawKey []byte) error {
  10. k.mu.Lock()
  11. defer k.mu.Unlock()
  12. if len(rawKey) == 0 {
  13. return errors.New(`non-empty []byte key required`)
  14. }
  15. k.octets = rawKey
  16. return nil
  17. }
  18. // Raw returns the octets for this symmetric key.
  19. // Since this is a symmetric key, this just calls Octets
  20. func (k *symmetricKey) Raw(v interface{}) error {
  21. k.mu.RLock()
  22. defer k.mu.RUnlock()
  23. return blackmagic.AssignIfCompatible(v, k.octets)
  24. }
  25. // Thumbprint returns the JWK thumbprint using the indicated
  26. // hashing algorithm, according to RFC 7638
  27. func (k *symmetricKey) Thumbprint(hash crypto.Hash) ([]byte, error) {
  28. k.mu.RLock()
  29. defer k.mu.RUnlock()
  30. var octets []byte
  31. if err := k.Raw(&octets); err != nil {
  32. return nil, errors.Wrap(err, `failed to materialize symmetric key`)
  33. }
  34. h := hash.New()
  35. fmt.Fprint(h, `{"k":"`)
  36. fmt.Fprint(h, base64.EncodeToString(octets))
  37. fmt.Fprint(h, `","kty":"oct"}`)
  38. return h.Sum(nil), nil
  39. }
  40. func (k *symmetricKey) PublicKey() (Key, error) {
  41. newKey := NewSymmetricKey()
  42. for _, pair := range k.makePairs() {
  43. //nolint:forcetypeassert
  44. key := pair.Key.(string)
  45. if err := newKey.Set(key, pair.Value); err != nil {
  46. return nil, errors.Wrapf(err, `failed to set field %q`, key)
  47. }
  48. }
  49. return newKey, nil
  50. }