Add grpc signer

2 files changed, 78 insertions, 4 deletions

diff --git a/cmd/cashierd/main.go b/cmd/cashierd/main.go
index 8164cf7..d355604 100644
--- a/cmd/cashierd/main.go
+++ b/cmd/cashierd/main.go
@@ -17,6 +17,7 @@ import (
 	"strings"
 
 	"github.com/pkg/errors"
+	"github.com/soheilhy/cmux"
 
 	"go4.org/wkfs"
 	"golang.org/x/crypto/acme/autocert"
@@ -153,8 +154,7 @@ func signHandler(a *appContext, w http.ResponseWriter, r *http.Request) (int, er
 	token := &oauth2.Token{
 		AccessToken: t,
 	}
-	ok := authprovider.Valid(token)
-	if !ok {
+	if !authprovider.Valid(token) {
 		return http.StatusUnauthorized, errors.New(http.StatusText(http.StatusUnauthorized))
 	}
 
@@ -174,7 +174,7 @@ func signHandler(a *appContext, w http.ResponseWriter, r *http.Request) (int, er
 	}
 	if err := json.NewEncoder(w).Encode(&lib.SignResponse{
 		Status:   "ok",
-		Response: lib.GetPublicKey(cert),
+		Response: string(lib.GetPublicKey(cert)),
 	}); err != nil {
 		return http.StatusInternalServerError, errors.Wrap(err, "error encoding response")
 	}
@@ -425,5 +425,11 @@ func main() {
 	s := &http.Server{
 		Handler: h,
 	}
-	log.Fatal(s.Serve(l))
+
+	cm := cmux.New(l)
+	httpl := cm.Match(cmux.HTTP1Fast())
+	grpcl := cm.Match(cmux.HTTP2HeaderField("content-type", "application/grpc"))
+	go s.Serve(httpl)
+	go newGrpcServer(grpcl)
+	log.Fatal(cm.Serve())
 }
diff --git a/cmd/cashierd/rpc.go b/cmd/cashierd/rpc.go
new file mode 100644
index 0000000..ad8aa5d
--- /dev/null
+++ b/cmd/cashierd/rpc.go
@@ -0,0 +1,68 @@
+package main
+
+import (
+	"log"
+	"net"
+
+	"golang.org/x/net/context"
+
+	"golang.org/x/oauth2"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/metadata"
+
+	"github.com/nsheridan/cashier/lib"
+	"github.com/nsheridan/cashier/proto"
+)
+
+type rpcServer struct{}
+
+type key int
+
+const usernameKey key = 0
+
+func (s *rpcServer) Sign(ctx context.Context, req *proto.SignRequest) (*proto.SignResponse, error) {
+	username, ok := ctx.Value(usernameKey).(string)
+	if !ok {
+		return nil, grpc.Errorf(codes.InvalidArgument, "Error reading username")
+	}
+	cert, err := keysigner.SignUserKeyFromRPC(req, username)
+	if err != nil {
+		return nil, grpc.Errorf(codes.InvalidArgument, err.Error())
+	}
+	if err := certstore.SetCert(cert); err != nil {
+		log.Printf("Error recording cert: %v", err)
+	}
+	resp := &proto.SignResponse{
+		Cert: lib.GetPublicKey(cert),
+	}
+	return resp, nil
+}
+
+func authInterceptor(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (resp interface{}, err error) {
+	md, ok := metadata.FromContext(ctx)
+	if !ok {
+		return nil, grpc.Errorf(codes.Unauthenticated, "request not authenticated")
+	}
+	switch md["security"][0] {
+	case "authorization":
+		token := &oauth2.Token{
+			AccessToken: md["payload"][0],
+		}
+		if !authprovider.Valid(token) {
+			return nil, grpc.Errorf(codes.PermissionDenied, "access denied")
+		}
+		authprovider.Revoke(token)
+		ctx = context.WithValue(ctx, usernameKey, authprovider.Username(token))
+	default:
+		return nil, grpc.Errorf(codes.InvalidArgument, "unknown argument")
+	}
+	return handler(ctx, req)
+}
+
+func newGrpcServer(l net.Listener) {
+	serv := grpc.NewServer(grpc.UnaryInterceptor(authInterceptor))
+	proto.RegisterSignerServer(serv, &rpcServer{})
+	serv.Serve(l)
+}