feat: Validate userdata (#593)

* feat: Validate userdata

Signed-off-by: Brad Beam <brad.beam@talos-systems.com>

pkg/userdata/networking_test.go

@@ -0,0 +1,60 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package userdata
+
+import (
+	"github.com/hashicorp/go-multierror"
+	"golang.org/x/xerrors"
+)
+
+func (suite *validateSuite) TestValidateDevice() {
+	var err error
+
+	// Test for missing required sections
+	dev := &Device{}
+	err = dev.Validate(CheckDeviceInterface())
+	suite.Require().Error(err)
+	// Embedding the check in suite.Assert().Equal(true, xerrors.Is had issues )
+	if !xerrors.Is(err.(*multierror.Error).Errors[0], ErrRequiredSection) {
+		suite.T().Errorf("%+v", err)
+
+	}
+
+	dev.Interface = "eth0"
+	err = dev.Validate(CheckDeviceInterface())
+	suite.Require().NoError(err)
+
+	err = dev.Validate(CheckDeviceAddressing())
+	suite.Require().Error(err)
+
+	// Ensure only a single addressing scheme is specified
+	dev.DHCP = true
+	dev.CIDR = "1.0.0.1/32"
+	err = dev.Validate(CheckDeviceAddressing())
+	suite.Require().Error(err)
+
+	dev.DHCP = false
+	err = dev.Validate(CheckDeviceAddressing())
+	suite.Require().NoError(err)
+
+	dev.Routes = []Route{}
+	err = dev.Validate(CheckDeviceRoutes())
+	suite.Require().NoError(err)
+
+	// nolint: gofmt
+	dev.Routes = []Route{Route{Gateway: "yolo"}}
+	err = dev.Validate(CheckDeviceRoutes())
+	suite.Require().Error(err)
+
+	// nolint: gofmt
+	dev.Routes = []Route{Route{Gateway: "yolo", Network: "totes"}}
+	err = dev.Validate(CheckDeviceRoutes())
+	suite.Require().Error(err)
+
+	// nolint: gofmt
+	dev.Routes = []Route{Route{Gateway: "192.168.1.1", Network: "192.168.1.0/24"}}
+	err = dev.Validate(CheckDeviceRoutes())
+	suite.Require().NoError(err)
+}