feat(linux): add templater utility and consolidate packer templates

packer.mk

@@ -8,58 +8,9 @@ ifeq (${ARCHITECTURE},ARM64)
 endif
 GOHOSTARCH = $(shell go env GOHOSTARCH)
 
-build-packer: generate-prefetch-scripts build-aks-node-controller build-lister-binary
-ifeq (${ARCHITECTURE},ARM64)
-	@echo "${MODE}: Building with Hyper-v generation 2 ARM64 VM"
-ifeq (${OS_SKU},Ubuntu)
-	@echo "Using packer template file vhd-image-builder-arm64-gen2.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-arm64-gen2.json
-else ifeq (${OS_SKU},CBLMariner)
-	@echo "Using packer template file vhd-image-builder-mariner-arm64.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-mariner-arm64.json
-else ifeq (${OS_SKU},AzureLinux)
-	@echo "Using packer template file vhd-image-builder-mariner-arm64.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-mariner-arm64.json
-else ifeq (${OS_SKU},Flatcar)
-	@echo "Using packer template file vhd-image-builder-flatcar-arm64.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-flatcar-arm64.json
-else
-	$(error OS_SKU was invalid ${OS_SKU})
-endif
-else ifeq (${ARCHITECTURE},X86_64)
-ifeq (${HYPERV_GENERATION},V2)
-	@echo "${MODE}: Building with Hyper-v generation 2 x86_64 VM"
-else ifeq (${HYPERV_GENERATION},V1)
-	@echo "${MODE}: Building with Hyper-v generation 1 X86_64 VM"
-else
-	$(error HYPERV_GENERATION was invalid ${HYPERV_GENERATION})
-endif
-ifeq (${OS_SKU},Ubuntu)
-ifeq ($(findstring cvm,$(FEATURE_FLAGS)),cvm)
-	@echo "Using packer template file vhd-image-builder-cvm.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-cvm.json
-else
-	@echo "Using packer template file vhd-image-builder-base.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-base.json
-endif
-else ifeq (${OS_SKU},CBLMariner)
-	@echo "Using packer template file vhd-image-builder-mariner.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-mariner.json
-else ifeq (${OS_SKU},AzureLinux)
-ifeq ($(findstring cvm,$(FEATURE_FLAGS)),cvm)
-	@echo "Using packer template file vhd-image-builder-mariner-cvm.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-mariner-cvm.json
-else
-	@echo "Using packer template file vhd-image-builder-mariner.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-mariner.json
-endif
-else ifeq (${OS_SKU},Flatcar)
-	@echo "Using packer template file vhd-image-builder-flatcar.json"
-	@packer build -timestamp-ui  -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/vhd-image-builder-flatcar.json
-else
-	$(error OS_SKU was invalid ${OS_SKU})
-endif
-endif
+build-packer: generate-prefetch-scripts build-aks-node-controller build-lister-binary generate-packer-template-linux
+	@echo "MODE: ${MODE}, HYPERV_GENERATION: ${HYPERV_GENERATION}, ARCHITECTURE: ${ARCHITECTURE}; Using generated packer template: linux-template.json"
+	@packer build -timestamp-ui -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/linux-template.json
 
 build-packer-windows:
 ifeq (${MODE},windowsVhdMode)
@@ -79,6 +30,10 @@ endif
 	@packer build -timestamp-ui -var-file=vhdbuilder/packer/settings.json vhdbuilder/packer/windows/windows-vhd-builder-sig.json
 endif
 
+generate-packer-template-linux:
+	@echo "Generating Linux packer template"
+	@bash -c "pushd vhdbuilder/packer/templater; go run main.go --output-path=../linux-template.json || exit 1; popd"
+
 build-imagecustomizer: generate-prefetch-scripts build-aks-node-controller build-lister-binary
 	@./vhdbuilder/packer/imagecustomizer/scripts/build-imagecustomizer-image.sh
 

vhdbuilder/packer/packer_source.sh

@@ -11,8 +11,6 @@ copyPackerFiles() {
   ETC_ISSUE_CONFIG_DEST=/etc/issue
   ETC_ISSUE_NET_CONFIG_SRC=/home/packer/etc-issue.net
   ETC_ISSUE_NET_CONFIG_DEST=/etc/issue.net
-  SSHD_CONFIG_SRC=/home/packer/sshd_config
-  SSHD_CONFIG_DEST=/etc/ssh/sshd_config
   MODPROBE_CIS_SRC=/home/packer/modprobe-CIS.conf
   MODPROBE_CIS_DEST=/etc/modprobe.d/CIS.conf
   FAILLOCK_CONF_SRC=/home/packer/faillock-CIS.conf
@@ -274,6 +272,8 @@ copyPackerFiles() {
   NOTICE_SRC=/home/packer/NOTICE.txt
   NOTICE_DEST=/NOTICE.txt
 
+  SSHD_CONFIG_SRC=/home/packer/sshd_config
+  SSHD_CONFIG_DEST=/etc/ssh/sshd_config
   if [ ${UBUNTU_RELEASE} = "22.04" ] && [ ${ENABLE_FIPS,,} = "true" ]; then
     SSHD_CONFIG_SRC=/home/packer/sshd_config_2204_fips
   fi

vhdbuilder/packer/templater/go.mod

@@ -0,0 +1,3 @@
+module github.com/Azure/AgentBaker/vhdbuilder/packer/templater
+
+go 1.23.6

vhdbuilder/packer/templater/internal/config/config.go

@@ -0,0 +1,154 @@
+package config
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+type VHD struct {
+	OS               string
+	OSVersion        string
+	HyperVGeneration string
+	Architecture     string
+	CGroupsV2        bool
+	FIPS             bool
+	TrustedLaunch    bool
+	FeatureFlags     FeatureFlags
+}
+
+type FeatureFlags struct {
+	CVM   bool
+	Kata  bool
+	GB200 bool
+}
+
+func LoadVHDConfigFromEnv() (VHD, error) {
+	os, err := getOSFromEnv()
+	if err != nil {
+		return VHD{}, fmt.Errorf("getting OS from environment: %w", err)
+	}
+	osVersion, err := getOSVersionFromEnv()
+	if err != nil {
+		return VHD{}, fmt.Errorf("getting OS version from environment: %w", err)
+	}
+	hyperVGeneration, err := getHyperVGenerationFromEnv()
+	if err != nil {
+		return VHD{}, fmt.Errorf("getting hyper-V generation version from environment: %w", err)
+	}
+	architecture, err := getArchitectureFromEnv()
+	if err != nil {
+		return VHD{}, fmt.Errorf("getting architecture from environment: %w", err)
+	}
+	cgroupsV2, err := getCGroupsV2FromEnv()
+	if err != nil {
+		return VHD{}, fmt.Errorf("determining cgroupsv2 enablement from environment: %w", err)
+	}
+	fips, err := getFIPSFromEnv()
+	if err != nil {
+		return VHD{}, fmt.Errorf("determining FIPS enablement from environment: %w", err)
+	}
+	trustedLaunch, err := getTrustedLaunchFromEnv()
+	if err != nil {
+		return VHD{}, fmt.Errorf("determining Trusted Launch enablement from environment: %w", err)
+	}
+	return VHD{
+		OS:               os,
+		OSVersion:        osVersion,
+		HyperVGeneration: hyperVGeneration,
+		Architecture:     architecture,
+		CGroupsV2:        cgroupsV2,
+		FIPS:             fips,
+		TrustedLaunch:    trustedLaunch,
+		FeatureFlags:     getFeatureFlagsFromEnv(),
+	}, nil
+}
+
+func getOSFromEnv() (string, error) {
+	os := os.Getenv("OS_SKU")
+	if os == "" {
+		return "", fmt.Errorf("environment variable OS_SKU must be set")
+	}
+	switch strings.ToLower(os) {
+	case "ubuntu":
+		return "Ubuntu", nil
+	case "cblmariner", "azurelinux", "azurelinuxosguard":
+		return "Mariner", nil
+	case "flatcar":
+		return "Flatcar", nil
+	default:
+		return "", fmt.Errorf("unrecognized OS: %s", os)
+	}
+}
+
+func getOSVersionFromEnv() (string, error) {
+	osVersion := os.Getenv("OS_VERSION")
+	if osVersion == "" {
+		return "", fmt.Errorf("environment variable OS_VERSION must be set")
+	}
+	return osVersion, nil
+}
+
+func getHyperVGenerationFromEnv() (string, error) {
+	hyperVGeneration := os.Getenv("HYPERV_GENERATION")
+	if hyperVGeneration == "" {
+		return "", fmt.Errorf("environment variable HYPERV_GENERATION must be set")
+	}
+	switch strings.ToLower(hyperVGeneration) {
+	case "v1", "v2":
+		return hyperVGeneration, nil
+	default:
+		return "", fmt.Errorf("unrecognized hyperV generation: %s", hyperVGeneration)
+	}
+}
+
+func getArchitectureFromEnv() (string, error) {
+	architecture := os.Getenv("ARCHITECTURE")
+	if architecture == "" {
+		return "", fmt.Errorf("environment variable ARCHITECTURE must be set")
+	}
+	switch strings.ToLower(architecture) {
+	case "x86_64", "arm64":
+		return architecture, nil
+	default:
+		return "", fmt.Errorf("unrecognized architecture: %s", architecture)
+	}
+}
+
+func getCGroupsV2FromEnv() (bool, error) {
+	cgroupsV2 := os.Getenv("ENABLE_CGROUPV2")
+	if cgroupsV2 == "" {
+		return false, nil
+	}
+	return strconv.ParseBool(cgroupsV2)
+}
+
+func getFIPSFromEnv() (bool, error) {
+	fips := os.Getenv("ENABLE_FIPS")
+	if fips == "" {
+		return false, nil
+	}
+	return strconv.ParseBool(fips)
+}
+
+func getTrustedLaunchFromEnv() (bool, error) {
+	trustedLaunch := os.Getenv("ENABLE_TRUSTED_LAUNCH")
+	if trustedLaunch == "" {
+		return false, nil
+	}
+	return strconv.ParseBool(trustedLaunch)
+}
+
+func getFeatureFlagsFromEnv() FeatureFlags {
+	featureFlags := os.Getenv("FEATURE_FLAGS")
+	if featureFlags == "" {
+		return FeatureFlags{}
+	}
+	flags := strings.ToLower(featureFlags)
+	return FeatureFlags{
+		CVM:   strings.Contains(flags, "cvm"),
+		Kata:  strings.Contains(flags, "kata"),
+		GB200: strings.Contains(flags, "gb200"),
+	}
+}

vhdbuilder/packer/templater/internal/template.go

@@ -0,0 +1,63 @@
+package template
+
+import (
+	"bytes"
+	_ "embed"
+	"strings"
+	"text/template"
+
+	"github.com/Azure/AgentBaker/vhdbuilder/packer/templater/internal/config"
+)
+
+var (
+	//go:embed templates/packer.gtpl
+	packerTemplate string
+)
+
+func BuildPackerTemplate(vhdConfig config.VHD) (string, error) {
+	tmpl := template.Must(template.New("packer").Funcs(getFuncMap(vhdConfig)).Parse(packerTemplate))
+	var buffer bytes.Buffer
+	if err := tmpl.Execute(&buffer, vhdConfig); err != nil {
+		return "", err
+	}
+	return buffer.String(), nil
+
+}
+
+func getFuncMap(vhdConfig config.VHD) template.FuncMap {
+	return template.FuncMap{
+		"ToLower": strings.ToLower,
+		"GetArchitectureExtension": func() string {
+			switch strings.ToLower(vhdConfig.Architecture) {
+			case "arm64":
+				return "arm64"
+			default:
+				return "amd64"
+			}
+		},
+		"GetRebootCommand": func() string {
+			switch strings.ToLower(vhdConfig.OS) {
+			case "flatcar":
+				return "reboot"
+			default:
+				return "sudo reboot"
+			}
+		},
+		"GetRebootPauseDuration": func() string {
+			switch strings.ToLower(vhdConfig.OS) {
+			case "flatcar":
+				return "0s"
+			default:
+				return "60s"
+			}
+		},
+		"GetWAAgentPath": func() string {
+			switch strings.ToLower(vhdConfig.OS) {
+			case "mariner":
+				return "waagent"
+			default:
+				return "/usr/sbin/waagent"
+			}
+		},
+	}
+}