initial commit

pkg/op/signer.go

@@ -0,0 +1,78 @@
+package op
+
+import (
+	"encoding/json"
+
+	"golang.org/x/net/context"
+	"gopkg.in/square/go-jose.v2"
+
+	"github.com/caos/oidc/pkg/oidc"
+)
+
+type Signer interface {
+	SignIDToken(claims *oidc.IDTokenClaims) (string, error)
+	SignAccessToken(claims *oidc.AccessTokenClaims) (string, error)
+	SignatureAlgorithm() jose.SignatureAlgorithm
+}
+
+type idTokenSigner struct {
+	signer    jose.Signer
+	storage   AuthStorage
+	algorithm jose.SignatureAlgorithm
+}
+
+func NewDefaultSigner(ctx context.Context, storage AuthStorage) (Signer, error) {
+	s := &idTokenSigner{
+		storage: storage,
+	}
+	if err := s.initialize(ctx); err != nil {
+		return nil, err
+	}
+	return s, nil
+}
+
+func (s *idTokenSigner) initialize(ctx context.Context) error {
+	var key *jose.SigningKey
+	var err error
+	key, err = s.storage.GetSigningKey(ctx)
+	if err != nil {
+		key, err = s.storage.SaveKeyPair(ctx)
+		if err != nil {
+			return err
+		}
+	}
+	s.signer, err = jose.NewSigner(*key, &jose.SignerOptions{})
+	if err != nil {
+		return err
+	}
+	s.algorithm = key.Algorithm
+	return nil
+}
+
+func (s *idTokenSigner) SignIDToken(claims *oidc.IDTokenClaims) (string, error) {
+	payload, err := json.Marshal(claims)
+	if err != nil {
+		return "", err
+	}
+	return s.Sign(payload)
+}
+
+func (s *idTokenSigner) SignAccessToken(claims *oidc.AccessTokenClaims) (string, error) {
+	payload, err := json.Marshal(claims)
+	if err != nil {
+		return "", err
+	}
+	return s.Sign(payload)
+}
+
+func (s *idTokenSigner) Sign(payload []byte) (string, error) {
+	result, err := s.signer.Sign(payload)
+	if err != nil {
+		return "", err
+	}
+	return result.CompactSerialize()
+}
+
+func (s *idTokenSigner) SignatureAlgorithm() jose.SignatureAlgorithm {
+	return s.algorithm
+}