Merge "Add rule for AVB signing an image"

filesystem/Android.bp

@@ -12,6 +12,7 @@ bootstrap_go_package {
         "soong-linkerconfig",
     ],
     srcs: [
+        "avb_add_hash_footer.go",
         "bootimg.go",
         "filesystem.go",
         "logical_partition.go",

filesystem/avb_add_hash_footer.go

@@ -0,0 +1,149 @@
+// Copyright (C) 2022 The Android Open Source Project
+//
+// 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 filesystem
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/google/blueprint/proptools"
+
+	"android/soong/android"
+)
+
+func init() {
+	android.RegisterModuleType("avb_add_hash_footer", avbAddHashFooterFactory)
+}
+
+type avbAddHashFooter struct {
+	android.ModuleBase
+
+	properties avbAddHashFooterProperties
+
+	output     android.OutputPath
+	installDir android.InstallPath
+}
+
+type avbAddHashFooterProperties struct {
+	// Source file of this image. Can reference a genrule type module with the ":module" syntax.
+	Src *string `android:"path,arch_variant"`
+
+	// Set the name of the output. Defaults to <module_name>.img.
+	Filename *string
+
+	// Name of the image partition. Defaults to the name of this module.
+	Partition_name *string
+
+	// Size of the partition. Defaults to dynamically calculating the size.
+	Partition_size *int64
+
+	// Path to the private key that avbtool will use to sign this image.
+	Private_key *string `android:"path"`
+
+	// Algorithm that avbtool will use to sign this image. Default is SHA256_RSA4096.
+	Algorithm *string
+
+	// The salt in hex. Required for reproducible builds.
+	Salt *string
+}
+
+// The AVB footer adds verification information to the image.
+func avbAddHashFooterFactory() android.Module {
+	module := &avbAddHashFooter{}
+	module.AddProperties(&module.properties)
+	android.InitAndroidArchModule(module, android.DeviceSupported, android.MultilibFirst)
+	return module
+}
+
+func (a *avbAddHashFooter) installFileName() string {
+	return proptools.StringDefault(a.properties.Filename, a.BaseModuleName()+".img")
+}
+
+func (a *avbAddHashFooter) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	builder := android.NewRuleBuilder(pctx, ctx)
+
+	if a.properties.Src == nil {
+		ctx.PropertyErrorf("src", "missing source file")
+		return
+	}
+	input := android.PathForModuleSrc(ctx, proptools.String(a.properties.Src))
+	a.output = android.PathForModuleOut(ctx, a.installFileName()).OutputPath
+	builder.Command().Text("cp").Input(input).Output(a.output)
+
+	cmd := builder.Command().BuiltTool("avbtool").Text("add_hash_footer")
+
+	partition_name := proptools.StringDefault(a.properties.Partition_name, a.BaseModuleName())
+	cmd.FlagWithArg("--partition_name ", partition_name)
+
+	if a.properties.Partition_size == nil {
+		cmd.Flag("--dynamic_partition_size")
+	} else {
+		partition_size := proptools.Int(a.properties.Partition_size)
+		cmd.FlagWithArg("--partition_size ", strconv.Itoa(partition_size))
+	}
+
+	key := android.PathForModuleSrc(ctx, proptools.String(a.properties.Private_key))
+	cmd.FlagWithInput("--key ", key)
+
+	algorithm := proptools.StringDefault(a.properties.Algorithm, "SHA256_RSA4096")
+	cmd.FlagWithArg("--algorithm ", algorithm)
+
+	if a.properties.Salt == nil {
+		ctx.PropertyErrorf("salt", "missing salt value")
+		return
+	}
+	cmd.FlagWithArg("--salt ", proptools.String(a.properties.Salt))
+
+	cmd.FlagWithOutput("--image ", a.output)
+
+	builder.Build("avbAddHashFooter", fmt.Sprintf("avbAddHashFooter %s", ctx.ModuleName()))
+
+	a.installDir = android.PathForModuleInstall(ctx, "etc")
+	ctx.InstallFile(a.installDir, a.installFileName(), a.output)
+}
+
+var _ android.AndroidMkEntriesProvider = (*avbAddHashFooter)(nil)
+
+// Implements android.AndroidMkEntriesProvider
+func (a *avbAddHashFooter) AndroidMkEntries() []android.AndroidMkEntries {
+	return []android.AndroidMkEntries{android.AndroidMkEntries{
+		Class:      "ETC",
+		OutputFile: android.OptionalPathForPath(a.output),
+		ExtraEntries: []android.AndroidMkExtraEntriesFunc{
+			func(ctx android.AndroidMkExtraEntriesContext, entries *android.AndroidMkEntries) {
+				entries.SetString("LOCAL_MODULE_PATH", a.installDir.String())
+				entries.SetString("LOCAL_INSTALLED_MODULE_STEM", a.installFileName())
+			},
+		},
+	}}
+}
+
+var _ Filesystem = (*avbAddHashFooter)(nil)
+
+func (a *avbAddHashFooter) OutputPath() android.Path {
+	return a.output
+}
+
+func (a *avbAddHashFooter) SignedOutputPath() android.Path {
+	return a.OutputPath() // always signed
+}
+
+// TODO(b/185115783): remove when not needed as input to a prebuilt_etc rule
+var _ android.SourceFileProducer = (*avbAddHashFooter)(nil)
+
+// Implements android.SourceFileProducer
+func (a *avbAddHashFooter) Srcs() android.Paths {
+	return append(android.Paths{}, a.output)
+}