Merge "Add kernel info to compatibility.zip" am: 5cc9230914
am: b35937ca55

Change-Id: I396a27bddf635afba797816688bb31a6558d6881
diff --git a/core/Makefile b/core/Makefile
index 4309e2c..fbf6d57 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -2586,10 +2586,71 @@
 $(BUILT_ASSEMBLED_VENDOR_MANIFEST): $(BUILT_SYSTEM_MATRIX)
 $(BUILT_ASSEMBLED_VENDOR_MANIFEST): $(BUILT_VENDOR_MANIFEST)
 $(BUILT_ASSEMBLED_VENDOR_MANIFEST): $(INTERNAL_VENDORIMAGE_FILES)
+
+$(BUILT_ASSEMBLED_VENDOR_MANIFEST): PRIVATE_FLAGS :=
+
+# -- Kernel version and configurations.
+ifeq ($(PRODUCT_OTA_ENFORCE_VINTF_KERNEL_REQUIREMENTS),true)
+
+# BOARD_KERNEL_CONFIG_FILE and BOARD_KERNEL_VERSION can be used to override the values extracted
+# from INSTALLED_KERNEL_TARGET.
+ifdef BOARD_KERNEL_CONFIG_FILE
+ifdef BOARD_KERNEL_VERSION
+$(BUILT_ASSEMBLED_VENDOR_MANIFEST): $(BOARD_KERNEL_CONFIG_FILE)
+$(BUILT_ASSEMBLED_VENDOR_MANIFEST): PRIVATE_FLAGS += --kernel $(BOARD_KERNEL_VERSION):$(BOARD_KERNEL_CONFIG_FILE)
+my_board_extracted_kernel := true
+endif # BOARD_KERNEL_VERSION
+endif # BOARD_KERNEL_CONFIG_FILE
+
+ifneq ($(my_board_extracted_kernel),true)
+ifndef INSTALLED_KERNEL_TARGET
+$(warning No INSTALLED_KERNEL_TARGET is defined when PRODUCT_OTA_ENFORCE_VINTF_KERNEL_REQUIREMENTS \
+    is true. Information about the updated kernel cannot be built into OTA update package. \
+    You can fix this by: (1) setting TARGET_NO_KERNEL to false and installing the built kernel \
+    to $(PRODUCT_OUT)/kernel, so that kernel information will be extracted from the built kernel; \
+    or (2) extracting kernel configuration and defining BOARD_KERNEL_CONFIG_FILE and \
+    BOARD_KERNEL_VERSION manually; or (3) unsetting PRODUCT_OTA_ENFORCE_VINTF_KERNEL_REQUIREMENTS \
+    manually.)
+else
+intermediates := $(call intermediates-dir-for,ETC,$(notdir $(BUILT_ASSEMBLED_VENDOR_MANIFEST)))
+
+# Tools for decompression that is not in PATH.
+# Check $(EXTRACT_KERNEL) for decompression algorithms supported by the script.
+# Algorithms that are in the script but not in this list will be found in PATH.
+my_decompress_tools := \
+    lz4:$(HOST_OUT_EXECUTABLES)/lz4 \
+
+my_kernel_configs := $(intermediates)/kernel_configs.txt
+my_kernel_version := $(intermediates)/kernel_version.txt
+$(my_kernel_configs): .KATI_IMPLICIT_OUTPUTS := $(my_kernel_version)
+$(my_kernel_configs): PRIVATE_KERNEL_VERSION_FILE := $(my_kernel_version)
+$(my_kernel_configs): PRIVATE_DECOMPRESS_TOOLS := $(my_decompress_tools)
+$(my_kernel_configs): $(foreach pair,$(my_decompress_tools),$(call word-colon,2,$(pair)))
+$(my_kernel_configs): $(EXTRACT_KERNEL) $(INSTALLED_KERNEL_TARGET)
+	$< --tools $(PRIVATE_DECOMPRESS_TOOLS) --input $(INSTALLED_KERNEL_TARGET) \
+	  --output-configs $@ \
+	  --output-version $(PRIVATE_KERNEL_VERSION_FILE)
+
+$(BUILT_ASSEMBLED_VENDOR_MANIFEST): $(my_kernel_configs) $(my_kernel_version)
+$(BUILT_ASSEMBLED_VENDOR_MANIFEST): PRIVATE_FLAGS += --kernel $$(cat $(my_kernel_version)):$(my_kernel_configs)
+
+intermediates :=
+my_kernel_configs :=
+my_kernel_version :=
+my_decompress_tools :=
+
+endif # my_board_extracted_kernel
+my_board_extracted_kernel :=
+
+endif # INSTALLED_KERNEL_TARGET
+endif # PRODUCT_OTA_ENFORCE_VINTF_KERNEL_REQUIREMENTS
+
+$(BUILT_ASSEMBLED_VENDOR_MANIFEST):
 	@echo "Verifying vendor VINTF manifest."
 	PRODUCT_ENFORCE_VINTF_MANIFEST=$(PRODUCT_ENFORCE_VINTF_MANIFEST) \
 	$(PRIVATE_SYSTEM_ASSEMBLE_VINTF_ENV_VARS) \
 	$(HOST_OUT_EXECUTABLES)/assemble_vintf \
+	    $(PRIVATE_FLAGS) \
 	    -c $(BUILT_SYSTEM_MATRIX) \
 	    -i $(BUILT_VENDOR_MANIFEST) \
 	    $$([ -d $(TARGET_OUT_VENDOR)/etc/vintf/manifest ] && \
diff --git a/core/config.mk b/core/config.mk
index 3a4e92f..e8cb1e5 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -730,6 +730,8 @@
 
 JETIFIER := prebuilts/sdk/tools/jetifier/jetifier-standalone/bin/jetifier-standalone
 
+EXTRACT_KERNEL := build/make/tools/extract_kernel.py
+
 COLUMN:= column
 
 USE_OPENJDK9 := true
diff --git a/tools/extract_kernel.py b/tools/extract_kernel.py
new file mode 100755
index 0000000..16ccb22
--- /dev/null
+++ b/tools/extract_kernel.py
@@ -0,0 +1,196 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2018 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.
+
+"""
+A tool to extract kernel information from a kernel image.
+"""
+
+import argparse
+import subprocess
+import sys
+import re
+
+CONFIG_PREFIX = b'IKCFG_ST'
+GZIP_HEADER = b'\037\213\010'
+COMPRESSION_ALGO = (
+    (["gzip", "-d"], GZIP_HEADER),
+    (["xz", "-d"], b'\3757zXZ\000'),
+    (["bzip2", "-d"], b'BZh'),
+    (["lz4", "-d", "-l"], b'\002\041\114\030'),
+
+    # These are not supported in the build system yet.
+    # (["unlzma"], b'\135\0\0\0'),
+    # (["lzop", "-d"], b'\211\114\132'),
+)
+
+# "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@"
+# LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n";
+LINUX_BANNER_PREFIX = b'Linux version '
+LINUX_BANNER_REGEX = LINUX_BANNER_PREFIX + \
+    r'([0-9]+[.][0-9]+[.][0-9]+).* \(.*@.*\) \(.*\) .*\n'
+
+
+def get_version(input_bytes, start_idx):
+  null_idx = input_bytes.find('\x00', start_idx)
+  if null_idx < 0:
+    return None
+  linux_banner = input_bytes[start_idx:null_idx].decode()
+  mo = re.match(LINUX_BANNER_REGEX, linux_banner)
+  if mo:
+    return mo.group(1)
+  return None
+
+
+def dump_version(input_bytes):
+  idx = 0
+  while True:
+    idx = input_bytes.find(LINUX_BANNER_PREFIX, idx)
+    if idx < 0:
+      return None
+
+    version = get_version(input_bytes, idx)
+    if version:
+      return version
+
+    idx += len(LINUX_BANNER_PREFIX)
+
+
+def dump_configs(input_bytes):
+  """
+  Dump kernel configuration from input_bytes. This can be done when
+  CONFIG_IKCONFIG is enabled, which is a requirement on Treble devices.
+
+  The kernel configuration is archived in GZip format right after the magic
+  string 'IKCFG_ST' in the built kernel.
+  """
+
+  # Search for magic string + GZip header
+  idx = input_bytes.find(CONFIG_PREFIX + GZIP_HEADER)
+  if idx < 0:
+    return None
+
+  # Seek to the start of the archive
+  idx += len(CONFIG_PREFIX)
+
+  sp = subprocess.Popen(["gzip", "-d", "-c"], stdin=subprocess.PIPE,
+                        stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+  o, _ = sp.communicate(input=input_bytes[idx:])
+  if sp.returncode == 1: # error
+    return None
+
+  # success or trailing garbage warning
+  assert sp.returncode in (0, 2), sp.returncode
+
+  return o
+
+
+def try_decompress(cmd, search_bytes, input_bytes):
+  idx = input_bytes.find(search_bytes)
+  if idx < 0:
+    return None
+
+  idx = 0
+  sp = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE,
+                        stderr=subprocess.PIPE)
+  o, _ = sp.communicate(input=input_bytes[idx:])
+  # ignore errors
+  return o
+
+
+def decompress_dump(func, input_bytes):
+  """
+  Run func(input_bytes) first; and if that fails (returns value evaluates to
+  False), then try different decompression algorithm before running func.
+  """
+  o = func(input_bytes)
+  if o:
+    return o
+  for cmd, search_bytes in COMPRESSION_ALGO:
+    decompressed = try_decompress(cmd, search_bytes, input_bytes)
+    if decompressed:
+      o = func(decompressed)
+      if o:
+        return o
+    # Force decompress the whole file even if header doesn't match
+    decompressed = try_decompress(cmd, b"", input_bytes)
+    if decompressed:
+      o = func(decompressed)
+      if o:
+        return o
+
+def main():
+  parser = argparse.ArgumentParser(
+      formatter_class=argparse.RawTextHelpFormatter,
+      description=__doc__ +
+      "\nThese algorithms are tried when decompressing the image:\n    " +
+      " ".join(tup[0][0] for tup in COMPRESSION_ALGO))
+  parser.add_argument('--input',
+                      help='Input kernel image. If not specified, use stdin',
+                      metavar='FILE',
+                      type=argparse.FileType('rb'),
+                      default=sys.stdin)
+  parser.add_argument('--output-configs',
+                      help='If specified, write configs. Use stdout if no file '
+                           'is specified.',
+                      metavar='FILE',
+                      nargs='?',
+                      type=argparse.FileType('wb'),
+                      const=sys.stdout)
+  parser.add_argument('--output-version',
+                      help='If specified, write version. Use stdout if no file '
+                           'is specified.',
+                      metavar='FILE',
+                      nargs='?',
+                      type=argparse.FileType('wb'),
+                      const=sys.stdout)
+  parser.add_argument('--tools',
+                      help='Decompression tools to use. If not specified, PATH '
+                           'is searched.',
+                      metavar='ALGORITHM:EXECUTABLE',
+                      nargs='*')
+  args = parser.parse_args()
+
+  tools = {pair[0]: pair[1]
+           for pair in (token.split(':') for token in args.tools or [])}
+  for cmd, _ in COMPRESSION_ALGO:
+    if cmd[0] in tools:
+      cmd[0] = tools[cmd[0]]
+
+  input_bytes = args.input.read()
+
+  ret = 0
+  if args.output_configs is not None:
+    o = decompress_dump(dump_configs, input_bytes)
+    if o:
+      args.output_configs.write(o)
+    else:
+      sys.stderr.write(
+          "Cannot extract kernel configs in {}".format(args.input.name))
+      ret = 1
+  if args.output_version is not None:
+    o = decompress_dump(dump_version, input_bytes)
+    if o:
+      args.output_version.write(o)
+    else:
+      sys.stderr.write(
+          "Cannot extract kernel versions in {}".format(args.input.name))
+      ret = 1
+
+  return ret
+
+
+if __name__ == '__main__':
+  exit(main())
diff --git a/tools/test_extract_kernel.py b/tools/test_extract_kernel.py
new file mode 100644
index 0000000..1a1cfcb
--- /dev/null
+++ b/tools/test_extract_kernel.py
@@ -0,0 +1,30 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2018 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 unittest
+from extract_kernel import get_version, dump_version
+
+class ExtractKernelTest(unittest.TestCase):
+  def test_extract_version(self):
+    self.assertEqual("4.9.100", get_version(
+        b'Linux version 4.9.100-a123 (a@a) (a) a\n\x00', 0))
+    self.assertEqual("4.9.123", get_version(
+        b'Linux version 4.9.123 (@) () \n\x00', 0))
+
+  def test_dump_self(self):
+    self.assertEqual("4.9.1", dump_version(
+        b"trash\x00Linux version 4.8.8\x00trash\x00"
+        "other trash Linux version 4.9.1-g3 (2@s) (2) a\n\x00"))