Function NewPublicKeySetFromJSON

auth/keys.go:127–161

NewPublicKeySetFromJSON will accept a JSON payload in the format of the JSONKeyResponse and parse it into a PublicKeySet.

(payload []byte, ttl time.Duration)

// NewPublicKeySetFromJSON will accept a JSON payload in the format of the
// JSONKeyResponse and parse it into a PublicKeySet.
func NewPublicKeySetFromJSON(payload []byte, ttl time.Duration) (PublicKeySet, error) {
	var (
		ks   PublicKeySet
		keys JSONKeyResponse
	)
	err := json.Unmarshal(payload, &keys)
	if err != nil {
		return ks, err
	}

	ks = PublicKeySet{
		Expiry: TimeNow().Add(ttl),
		Keys:   map[string]*rsa.PublicKey{},
	}

	for _, key := range keys.Keys {
		// we only plan on using RSA
		if key.Use == "sig" && key.Kty == "RSA" {
			n, err := base64.RawURLEncoding.DecodeString(key.N)
			if err != nil {
				return ks, err
			}
			e, err := base64.RawURLEncoding.DecodeString(key.E)
			if err != nil {
				return ks, err
			}
			ei := big.NewInt(0).SetBytes(e).Int64()
			ks.Keys[key.Kid] = &rsa.PublicKey{
				N: big.NewInt(0).SetBytes(n),
				E: int(ei),
			}
		}
	}
	return ks, nil
}

// TimeNow is used internally to determine the current time. It has been abstracted to
// this global function as a mechanism to help with testing.