Initial implementation of layoutlib SBOM generation.

1) Build/dist build.prop, resource files
2) Generate layoutlib SBOM that includes build.prop, resource files,
   font files and font configuration files
3) Generate SBOM of framework_res.jar with placeholders for substitution
   in release_layoutlib.sh

Bug: 303903787
Bug: 303904046
Bug: 303904808
Bug: 303905932
Bug: 303906000
Bug: 303906275
Test: lunch sdk_phone64_arm64-userdebug && m layoutlib dist
Change-Id: Ib004e199e740ccc901e93b11201db2477464be1d
diff --git a/core/layoutlib_fonts.mk b/core/layoutlib_fonts.mk
index d2a814f..e7b3a76 100644
--- a/core/layoutlib_fonts.mk
+++ b/core/layoutlib_fonts.mk
@@ -33,3 +33,84 @@
 font_config :=
 fonts_device :=
 FONT_FILES :=
+
+# The following build process of build.prop, layoutlib-res.zip is moved here from release_layoutlib.sh
+# so the SBOM of all platform neutral artifacts and Linux/Windows artifacts of layoutlib can be built in Make/Soong.
+# See go/layoutlib-sbom.
+
+# build.prop shipped with layoutlib
+LAYOUTLIB_BUILD_PROP := $(call intermediates-dir-for,PACKAGING,layoutlib-build-prop,HOST,COMMON)
+$(LAYOUTLIB_BUILD_PROP)/layoutlib-build.prop: $(INSTALLED_SDK_BUILD_PROP_TARGET)
+	rm -rf $@
+	cp $< $@
+	# Remove all the uncommon build properties
+	sed -i '/^ro\.\(build\|product\|config\|system\)/!d' $@
+	# Mark the build as layoutlib. This can be read at runtime by apps
+	sed -i 's|ro.product.brand=generic|ro.product.brand=studio|' $@
+	sed -i 's|ro.product.device=generic|ro.product.device=layoutlib|' $@
+
+$(call dist-for-goals,layoutlib,$(LAYOUTLIB_BUILD_PROP)/layoutlib-build.prop:layoutlib_native/build.prop)
+
+# Resource files from frameworks/base/core/res/res
+LAYOUTLIB_RES := $(call intermediates-dir-for,PACKAGING,layoutlib-res,HOST,COMMON)
+LAYOUTLIB_RES_FILES := $(shell find frameworks/base/core/res/res -type f -not -path 'frameworks/base/core/res/res/values-m[nc]c*' | sort)
+$(LAYOUTLIB_RES)/layoutlib-res.zip: $(SOONG_ZIP) $(HOST_OUT_EXECUTABLES)/aapt2 $(LAYOUTLIB_RES_FILES)
+	rm -rf $@
+	echo $(LAYOUTLIB_RES_FILES) > $(LAYOUTLIB_RES)/filelist.txt
+	$(SOONG_ZIP) -C frameworks/base/core/res -l $(LAYOUTLIB_RES)/filelist.txt -o $(LAYOUTLIB_RES)/temp.zip
+	rm -rf $(LAYOUTLIB_RES)/data && unzip -q -d $(LAYOUTLIB_RES)/data $(LAYOUTLIB_RES)/temp.zip
+	rm -rf $(LAYOUTLIB_RES)/compiled && mkdir $(LAYOUTLIB_RES)/compiled && $(HOST_OUT_EXECUTABLES)/aapt2 compile $(LAYOUTLIB_RES)/data/res/**/*.9.png -o $(LAYOUTLIB_RES)/compiled
+	printf '<?xml version="1.0" encoding="utf-8"?>\n<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.google.android.layoutlib" />' > $(LAYOUTLIB_RES)/AndroidManifest.xml
+	$(HOST_OUT_EXECUTABLES)/aapt2 link -R $(LAYOUTLIB_RES)/compiled/* -o $(LAYOUTLIB_RES)/compiled.apk --manifest $(LAYOUTLIB_RES)/AndroidManifest.xml
+	rm -rf $(LAYOUTLIB_RES)/compiled_apk && unzip -q -d $(LAYOUTLIB_RES)/compiled_apk $(LAYOUTLIB_RES)/compiled.apk
+	for f in $(LAYOUTLIB_RES)/compiled_apk/res/*; do mv "$$f" "$${f/-v4/}";done
+	for f in $(LAYOUTLIB_RES)/compiled_apk/res/**/*.9.png; do mv "$$f" "$${f/.9.png/.compiled.9.png}";done
+	cp -r $(LAYOUTLIB_RES)/compiled_apk/res $(LAYOUTLIB_RES)/data
+	$(SOONG_ZIP) -C $(LAYOUTLIB_RES)/data -D $(LAYOUTLIB_RES)/data/res -o $@
+
+$(call dist-for-goals,layoutlib,$(LAYOUTLIB_RES)/layoutlib-res.zip:layoutlib_native/res.zip)
+
+# SBOM of layoutlib artifacts
+LAYOUTLIB_SBOM := $(call intermediates-dir-for,PACKAGING,layoutlib-sbom,HOST)
+_layoutlib_font_config_files := $(sort $(wildcard frameworks/base/data/fonts/*.xml))
+_layoutlib_fonts_files := $(filter $(TARGET_OUT)/fonts/%.ttf $(TARGET_OUT)/fonts/%.ttc $(TARGET_OUT)/fonts/%.otf, $(INTERNAL_SYSTEMIMAGE_FILES))
+$(LAYOUTLIB_SBOM)/sbom-metadata.csv:
+	rm -rf $@
+	echo installed_file,module_path,soong_module_type,is_prebuilt_make_module,product_copy_files,kernel_module_copy_files,is_platform_generated,build_output_path,static_libraries,whole_static_libraries,is_static_lib >> $@
+	echo build.prop,,,,,,Y,$(LAYOUTLIB_BUILD_PROP)/layoutlib-build.prop,,, >> $@
+
+	$(foreach f,$(_layoutlib_font_config_files),\
+	  echo data/fonts/$(notdir $f),frameworks/base/data/fonts,prebuilt_etc,,,,,$f,,, >> $@; \
+	)
+
+	$(foreach f,$(_layoutlib_fonts_files), \
+	  $(eval _module_name := $(ALL_INSTALLED_FILES.$f)) \
+	  $(eval _module_path := $(strip $(sort $(ALL_MODULES.$(_module_name).PATH)))) \
+	  $(eval _soong_module_type := $(strip $(sort $(ALL_MODULES.$(_module_name).SOONG_MODULE_TYPE)))) \
+	  echo data/fonts/$(notdir $f),$(_module_path),$(_soong_module_type),,,,,$f,,, >> $@; \
+	)
+
+	$(foreach f,$(LAYOUTLIB_RES_FILES), \
+	  $(eval _path := $(subst frameworks/base/core/res,data,$f)) \
+	  echo $(_path),,,,,,Y,$f,,, >> $@; \
+	)
+
+.PHONY: layoutlib-sbom
+layoutlib-sbom: $(LAYOUTLIB_SBOM)/layoutlib.spdx.json
+$(LAYOUTLIB_SBOM)/layoutlib.spdx.json: $(PRODUCT_OUT)/always_dirty_file.txt $(LAYOUTLIB_SBOM)/sbom-metadata.csv $(_layoutlib_font_config_files) $(_layoutlib_fonts_files) $(LAYOUTLIB_BUILD_PROP)/layoutlib-build.prop $(LAYOUTLIB_RES_FILES)
+	rm -rf $@
+	$(GEN_SBOM) --output_file $@ --metadata $(LAYOUTLIB_SBOM)/sbom-metadata.csv --build_version $(BUILD_FINGERPRINT_FROM_FILE) --product_mfr "$(PRODUCT_MANUFACTURER)" --json
+
+$(call dist-for-goals,layoutlib,$(LAYOUTLIB_SBOM)/layoutlib.spdx.json:layoutlib_native/sbom/layoutlib.spdx.json)
+
+# Generate SBOM of framework_res.jar that is created in release_layoutlib.sh.
+# The generated SBOM contains placeholders for release_layotlib.sh to substitute, and the placeholders include:
+# document name, document namespace, document creation info, organization and SHA1 value of framework_res.jar.
+GEN_SBOM_FRAMEWORK_RES := $(HOST_OUT_EXECUTABLES)/generate-sbom-framework_res
+.PHONY: layoutlib-framework_res-sbom
+layoutlib-framework_res-sbom: $(LAYOUTLIB_SBOM)/framework_res.jar.spdx.json
+$(LAYOUTLIB_SBOM)/framework_res.jar.spdx.json: $(LAYOUTLIB_SBOM)/layoutlib.spdx.json $(GEN_SBOM_FRAMEWORK_RES)
+	rm -rf $@
+	$(GEN_SBOM_FRAMEWORK_RES) --output_file $(LAYOUTLIB_SBOM)/framework_res.jar.spdx.json --layoutlib_sbom $(LAYOUTLIB_SBOM)/layoutlib.spdx.json
+
+$(call dist-for-goals,layoutlib,$(LAYOUTLIB_SBOM)/framework_res.jar.spdx.json:layoutlib_native/sbom/framework_res.jar.spdx.json)
\ No newline at end of file
diff --git a/tools/sbom/Android.bp b/tools/sbom/Android.bp
index 519251e..27a160e 100644
--- a/tools/sbom/Android.bp
+++ b/tools/sbom/Android.bp
@@ -77,3 +77,18 @@
     },
     test_suites: ["general-tests"],
 }
+
+python_binary_host {
+    name: "generate-sbom-framework_res",
+        srcs: [
+            "generate-sbom-framework_res.py",
+        ],
+        version: {
+            py3: {
+                embedded_launcher: true,
+            },
+        },
+        libs: [
+            "sbom_lib",
+        ],
+}
\ No newline at end of file
diff --git a/tools/sbom/generate-sbom-framework_res.py b/tools/sbom/generate-sbom-framework_res.py
new file mode 100644
index 0000000..d6be734
--- /dev/null
+++ b/tools/sbom/generate-sbom-framework_res.py
@@ -0,0 +1,80 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2023 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.
+
+import argparse
+import hashlib
+import json
+import sbom_data
+import sbom_writers
+
+
+def get_args():
+  parser = argparse.ArgumentParser()
+  parser.add_argument('-v', '--verbose', action='store_true', default=False,
+                      help='Print more information.')
+  parser.add_argument('--output_file', required=True,
+                      help='The generated SBOM file in SPDX format.')
+  parser.add_argument('--layoutlib_sbom', required=True,
+                      help='The file path of the SBOM of layoutlib.')
+
+  return parser.parse_args()
+
+
+def main():
+  global args
+  args = get_args()
+
+  doc = sbom_data.Document(name='<name>',
+                           namespace='<namespace>',
+                           creators=['Organization: <organization>'],
+                           created='<created>')
+
+  filename = 'data/framework_res.jar'
+  file_id = f'SPDXRef-{sbom_data.encode_for_spdxid(filename)}'
+  file = sbom_data.File(id=file_id, name=filename, checksum='SHA1: <checksum>')
+  doc.files.append(file)
+  doc.describes = file_id
+
+  with open(args.layoutlib_sbom, 'r', encoding='utf-8') as f:
+    layoutlib_sbom = json.load(f)
+
+  with open(args.layoutlib_sbom, 'rb') as f:
+    sha1 = hashlib.file_digest(f, 'sha1')
+
+  layoutlib_sbom_namespace = layoutlib_sbom[sbom_writers.PropNames.DOCUMENT_NAMESPACE]
+  external_doc_ref = 'DocumentRef-layoutlib'
+  doc.external_refs = [
+    sbom_data.DocumentExternalReference(external_doc_ref, layoutlib_sbom_namespace,
+                                        f'SHA1: {sha1.hexdigest()}')]
+
+  resource_file_spdxids = []
+  for file in layoutlib_sbom[sbom_writers.PropNames.FILES]:
+    if file[sbom_writers.PropNames.FILE_NAME].startswith('data/res/'):
+      resource_file_spdxids.append(file[sbom_writers.PropNames.SPDXID])
+
+  doc.relationships = []
+  for spdxid in resource_file_spdxids:
+    doc.relationships.append(
+      sbom_data.Relationship(file_id, sbom_data.RelationshipType.GENERATED_FROM,
+                             f'{external_doc_ref}:{spdxid}'))
+
+  # write sbom file
+  with open(args.output_file, 'w', encoding='utf-8') as f:
+    sbom_writers.JSONWriter.write(doc, f)
+
+
+if __name__ == '__main__':
+  main()
diff --git a/tools/sbom/generate-sbom.py b/tools/sbom/generate-sbom.py
index b19be87..4d090eb 100755
--- a/tools/sbom/generate-sbom.py
+++ b/tools/sbom/generate-sbom.py
@@ -103,26 +103,12 @@
       print(i)
 
 
-def encode_for_spdxid(s):
-  """Simple encode for string values used in SPDXID which uses the charset of A-Za-Z0-9.-"""
-  result = ''
-  for c in s:
-    if c.isalnum() or c in '.-':
-      result += c
-    elif c in '_@/':
-      result += '-'
-    else:
-      result += '0x' + c.encode('utf-8').hex()
-
-  return result.lstrip('-')
-
-
 def new_package_id(package_name, type):
-  return f'SPDXRef-{type}-{encode_for_spdxid(package_name)}'
+  return f'SPDXRef-{type}-{sbom_data.encode_for_spdxid(package_name)}'
 
 
 def new_file_id(file_path):
-  return f'SPDXRef-{encode_for_spdxid(file_path)}'
+  return f'SPDXRef-{sbom_data.encode_for_spdxid(file_path)}'
 
 
 def checksum(file_path):
diff --git a/tools/sbom/sbom_data.py b/tools/sbom/sbom_data.py
index 71f8660..b5ac8a5 100644
--- a/tools/sbom/sbom_data.py
+++ b/tools/sbom/sbom_data.py
@@ -138,3 +138,16 @@
       h = hashlib.sha1()
       h.update(''.join(checksums).encode(encoding='utf-8'))
       package.verification_code = h.hexdigest()
+
+def encode_for_spdxid(s):
+  """Simple encode for string values used in SPDXID which uses the charset of A-Za-Z0-9.-"""
+  result = ''
+  for c in s:
+    if c.isalnum() or c in '.-':
+      result += c
+    elif c in '_@/':
+      result += '-'
+    else:
+      result += '0x' + c.encode('utf-8').hex()
+
+  return result.lstrip('-')
\ No newline at end of file