new(pkg/driver): added tests for driver distros implementations.

Moreover, fixed some discovered issues.

Signed-off-by: Federico Di Pierro <nierro92@gmail.com>

pkg/driver/distro/amzn.go

@@ -16,8 +16,6 @@
 package driverdistro
 
 import (
-	"fmt"
-
 	"github.com/falcosecurity/driverkit/pkg/kernelrelease"
 	"gopkg.in/ini.v1"
 )
@@ -32,10 +30,9 @@ type amzn struct {
 
 //nolint:gocritic // the method shall not be able to modify kr
 func (a *amzn) init(kr kernelrelease.KernelRelease, _ string, cfg *ini.File) error {
-	idKey := cfg.Section("").Key("VERSION_ID")
-	if idKey == nil {
-		// OS-release without `VERSION_ID` (can it happen?)
-		return fmt.Errorf("no VERSION_ID present for amzn")
+	idKey, err := cfg.Section("").GetKey("VERSION_ID")
+	if err != nil {
+		return err
 	}
 	// overwrite id
 	newID := ""

pkg/driver/distro/amzn_test.go

@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (C) 2023 The Falco Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package driverdistro
+
+import (
+	"testing"
+
+	"github.com/falcosecurity/driverkit/pkg/kernelrelease"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"gopkg.in/ini.v1"
+)
+
+func TestDistroAmznInit(t *testing.T) {
+	type config struct {
+		VersionID string `ini:"VERSION_ID"`
+	}
+	type testCase struct {
+		cfg         interface{}
+		strExpected string
+		errExpected bool
+	}
+	testCases := []testCase{
+		{
+			cfg:         &config{VersionID: ""},
+			strExpected: "amazonlinux",
+		},
+		{
+			cfg:         &config{VersionID: "2"},
+			strExpected: "amazonlinux2",
+		},
+		{
+			cfg:         &config{VersionID: "2022"},
+			strExpected: "amazonlinux2022",
+		},
+		{
+			cfg:         &config{VersionID: "2023"},
+			strExpected: "amazonlinux2023",
+		},
+		{
+			cfg:         &struct{}{},
+			errExpected: true,
+		},
+	}
+	for _, tCase := range testCases {
+		al := &amzn{generic: &generic{}}
+		cfg := ini.Empty()
+		err := cfg.ReflectFrom(tCase.cfg)
+		require.NoError(t, err)
+
+		kr := kernelrelease.KernelRelease{}
+		err = al.init(kr, "", cfg)
+		if tCase.errExpected {
+			assert.Error(t, err)
+		} else {
+			assert.NoError(t, err)
+			assert.Equal(t, tCase.strExpected, al.String())
+		}
+	}
+}

pkg/driver/distro/bottlerocket.go

@@ -35,16 +35,15 @@ type bottlerocket struct {
 
 //nolint:gocritic // the method shall not be able to modify kr
 func (b *bottlerocket) init(kr kernelrelease.KernelRelease, id string, cfg *ini.File) error {
-	idKey := cfg.Section("").Key("VERSION_ID")
-	if idKey == nil {
-		// OS-release without `VERSION_ID` (can it happen?)
-		return fmt.Errorf("no VERSION_ID present for bottlerocket")
+	idKey, err := cfg.Section("").GetKey("VERSION_ID")
+	if err != nil {
+		return err
 	}
 	b.versionID = idKey.String()
 
-	idKey = cfg.Section("").Key("VARIANT_ID")
-	if idKey == nil {
-		return fmt.Errorf("no VARIANT_ID present for bottlerocket")
+	idKey, err = cfg.Section("").GetKey("VARIANT_ID")
+	if err != nil {
+		return err
 	}
 	b.variantID = strings.Split(idKey.String(), "-")[0]
 

pkg/driver/distro/bottlerocket_test.go

@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (C) 2023 The Falco Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package driverdistro
+
+import (
+	"testing"
+
+	"github.com/falcosecurity/driverkit/pkg/kernelrelease"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"gopkg.in/ini.v1"
+)
+
+func TestDistroBottlerocketFixup(t *testing.T) {
+	type config struct {
+		VersionID string `ini:"VERSION_ID"`
+		VariantID string `ini:"VARIANT_ID"`
+	}
+	type nonVersionConfig struct {
+		VariantID string `ini:"VARIANT_ID"`
+	}
+	type nonVariantConfig struct {
+		VersionID string `ini:"VERSION_ID"`
+	}
+
+	type testCase struct {
+		cfg         interface{}
+		kvExpected  string
+		errExpected bool
+	}
+	testCases := []testCase{
+		{
+			cfg:        &config{VersionID: "1.11.0", VariantID: "aws-k8s-1.15"},
+			kvExpected: "1_1.11.0-aws",
+		},
+		{
+			cfg:        &config{VersionID: "1.17.0", VariantID: "aws"},
+			kvExpected: "1_1.17.0-aws",
+		},
+		{
+			cfg:         &nonVersionConfig{VariantID: "aws"},
+			errExpected: true,
+		},
+		{
+			cfg:         &nonVariantConfig{VersionID: "1.11.0"},
+			errExpected: true,
+		},
+	}
+
+	for _, tCase := range testCases {
+		br := &bottlerocket{generic: &generic{}}
+		cfg := ini.Empty()
+		err := cfg.ReflectFrom(tCase.cfg)
+		require.NoError(t, err)
+
+		kr := kernelrelease.KernelRelease{}
+		err = br.init(kr, "", cfg)
+		if tCase.errExpected {
+			assert.Error(t, err)
+		} else {
+			assert.NoError(t, err)
+			fixedKr := br.FixupKernel(kr)
+			assert.Equal(t, tCase.kvExpected, fixedKr.KernelVersion)
+		}
+	}
+}

pkg/driver/distro/centos_test.go

@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (C) 2023 The Falco Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package driverdistro
+
+import (
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestDistroCentosCheck(t *testing.T) {
+	type testCase struct {
+		hostRoot    string
+		preFn       func() error
+		postFn      func()
+		retExpected bool
+	}
+	testCases := []testCase{
+		{
+			// No centos-release file
+			hostRoot: "/foo",
+			preFn: func() error {
+				return nil
+			},
+			postFn:      func() {},
+			retExpected: false,
+		},
+		{
+			// centos-release file present under hostroot
+			hostRoot: ".",
+			preFn: func() error {
+				if err := os.MkdirAll("./etc/", 0o755); err != nil {
+					return err
+				}
+				_, err := os.Create("./etc/centos-release")
+				return err
+			},
+			postFn: func() {
+				_ = os.RemoveAll("./etc/centos-release")
+			},
+			retExpected: true,
+		},
+		{
+			// centos-release file present but not under hostroot
+			hostRoot: "/foo",
+			preFn: func() error {
+				if err := os.MkdirAll("./etc/", 0o755); err != nil {
+					return err
+				}
+				_, err := os.Create("./etc/centos-release")
+				return err
+			},
+			postFn: func() {
+				_ = os.RemoveAll("./etc/centos-release")
+			},
+			retExpected: false,
+		},
+	}
+
+	for _, tCase := range testCases {
+		c := &centos{generic: &generic{}}
+		err := tCase.preFn()
+		require.NoError(t, err)
+		assert.Equal(t, tCase.retExpected, c.check(tCase.hostRoot))
+		tCase.postFn()
+	}
+}

pkg/driver/distro/cos.go

@@ -44,13 +44,13 @@ type cos struct {
 }
 
 //nolint:gocritic // the method shall not be able to modify kr
-func (c *cos) init(kr kernelrelease.KernelRelease, _ string, cfg *ini.File) error {
-	idKey := cfg.Section("").Key("BUILD_ID")
-	if idKey == nil {
-		// OS-release without `VERSION_ID` (can it happen?)
-		return fmt.Errorf("no BUILD_ID present for COS")
+func (c *cos) init(kr kernelrelease.KernelRelease, id string, cfg *ini.File) error {
+	idKey, err := cfg.Section("").GetKey("BUILD_ID")
+	if err != nil {
+		return err
 	}
-	return c.generic.init(kr, idKey.String(), cfg)
+	c.buildID = idKey.String()
+	return c.generic.init(kr, id, cfg)
 }
 
 //nolint:gocritic // the method shall not be able to modify kr

pkg/driver/distro/cos_test.go

@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (C) 2023 The Falco Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package driverdistro
+
+import (
+	"testing"
+
+	"github.com/falcosecurity/driverkit/pkg/kernelrelease"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"gopkg.in/ini.v1"
+)
+
+func TestDistroCosInit(t *testing.T) {
+	type config struct {
+		BuildID string `ini:"BUILD_ID"`
+	}
+
+	type testCase struct {
+		cfg         interface{}
+		buildID     string
+		errExpected bool
+	}
+	testCases := []testCase{
+		{
+			cfg:     &config{BuildID: "17162.127.33"},
+			buildID: "17162.127.33",
+		},
+		{
+			cfg:         &struct{}{},
+			errExpected: true,
+		},
+	}
+
+	for _, tCase := range testCases {
+		co := &cos{generic: &generic{}}
+		cfg := ini.Empty()
+		err := cfg.ReflectFrom(tCase.cfg)
+		require.NoError(t, err)
+
+		kr := kernelrelease.KernelRelease{}
+		err = co.init(kr, "", cfg)
+		if tCase.errExpected {
+			assert.Error(t, err)
+		} else {
+			assert.NoError(t, err)
+			assert.Equal(t, tCase.buildID, co.buildID)
+		}
+	}
+}