#!/bin/sh
# Copyright 2018 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# gen_test_images.sh BOARD IMAGE
# Generate test images from any premp/mp signed image.

set -e

BOARD=$1
IMAGE=$(readlink -f "$2")
DIRNAME=$(dirname "$(readlink -f "$0")")
KEY=${DIRNAME}/fingerprint_dev_keys/${BOARD}/dev_key.pem
# Increment to different rollback versions
ROLLBACK0=00000000
ROLLBACK1=01000000
ROLLBACK9=09000000

rm -rf images
mkdir images
cd images

# Use original image for some tests.
cp "${IMAGE}" "${BOARD}.bin"

# Use futility included in autotest source no matter if we are in chroot or lxc
# container, so that it's easier to notice if things break.
alias futility='${DIRNAME}'/futility

# Generate dev key set
futility create --desc="${BOARD} dev key" "${KEY}" key

# Pick up RO and RW version (only take up to 27 bytes, to leave an extra
# 4 bytes for .dev/.rbX tag, and terminating \0.
ro_version_offset=$(futility dump_fmap "${IMAGE}" RO_FRID | \
  sed -n 's/area_offset: *//p')
ro_version=$(dd if="${IMAGE}" bs=1 skip=$((ro_version_offset)) count=27)
rw_version_offset=$(futility dump_fmap "${IMAGE}" RW_FWID | \
  sed -n 's/area_offset: *//p')
rw_version=$(dd if="${IMAGE}" bs=1 skip=$((rw_version_offset)) count=27)

# Hack the version string
cp "${IMAGE}" "${BOARD}.dev"
printf '%s' "${ro_version}.dev" | \
  dd of="${BOARD}.dev" bs=1 seek=$((ro_version_offset)) count=32 conv=notrunc
printf '%s' "${rw_version}.dev" | \
  dd of="${BOARD}.dev" bs=1 seek=$((rw_version_offset)) count=32 conv=notrunc

# Resign the image with dev key
echo "Generating image signed with dev keys:"
KEY_NAME=key.vbprik2
futility sign --type rwsig --prikey "${KEY_NAME}" --version 1 "${BOARD}.dev"

# Show signature
futility show "${BOARD}.dev"

echo "Generating image with rollback = 0:"

printf "Current rollback version: "
rb_offset=$(futility dump_fmap "${BOARD}.dev" RW_RBVER \
  | sed -n 's/area_offset: *//p')
dd if="${BOARD}.dev" bs=1 skip=$((rb_offset)) count=4 2>/dev/null | xxd -l 4 -p

cp "${BOARD}.dev" "${BOARD}.dev.rb0"
# Decrement rollback to 0
echo "${ROLLBACK0}" | \
  xxd -g 4 -p -r | \
  dd of="${BOARD}.dev.rb0" bs=1 seek=$((rb_offset)) count=4 conv=notrunc
# Hack the version string
printf '%s' "${rw_version}.rb0" | \
  dd of="${BOARD}.dev.rb0" bs=1 seek=$((rw_version_offset)) \
  count=32 conv=notrunc
# Resign the image with dev key
futility sign --type rwsig --prikey "${KEY_NAME}" --version 1 "${BOARD}.dev.rb0"


echo "Generating image with rollback = 1:"

printf "Current rollback version: "
rb_offset=$(futility dump_fmap "${BOARD}.dev" RW_RBVER | \
  sed -n 's/area_offset: *//p')
dd if="${BOARD}.dev" bs=1 skip=$((rb_offset)) count=4 2>/dev/null | xxd -l 4 -p

cp "${BOARD}.dev" "${BOARD}.dev.rb1"
# Increment rollback to 1
echo "${ROLLBACK1}" | \
  xxd -g 4 -p -r | \
  dd of="${BOARD}.dev.rb1" bs=1 seek=$((rb_offset)) count=4 conv=notrunc
# Hack the version string
printf '%s' "${rw_version}.rb1" | \
  dd of="${BOARD}.dev.rb1" bs=1 seek=$((rw_version_offset)) \
  count=32 conv=notrunc
# Resign the image with dev key
futility sign --type rwsig --prikey "${KEY_NAME}" --version 1 "${BOARD}.dev.rb1"

echo "Generating image with rollback = 9:"

printf "Current rollback version: "
rb_offset=$(futility dump_fmap "${BOARD}.dev" RW_RBVER | \
  sed -n 's/area_offset: *//p')
dd if="${BOARD}.dev" bs=1 skip=$((rb_offset)) count=4 2>/dev/null | xxd -l 4 -p

cp "${BOARD}.dev" "${BOARD}.dev.rb9"
# Increment rollback to 9
echo "${ROLLBACK9}" | \
  xxd -g 4 -p -r | \
  dd of="${BOARD}.dev.rb9" bs=1 seek=$((rb_offset)) count=4 conv=notrunc
# Hack the version string
printf '%s' "${rw_version}.rb9" | \
  dd of="${BOARD}.dev.rb9" bs=1 seek=$((rw_version_offset)) \
  count=32 conv=notrunc
# Resign the image with dev key
futility sign --type rwsig --prikey "${KEY_NAME}" --version 1 "${BOARD}.dev.rb9"


echo "Generating image with bits corrupted at start of image:"
cp "${IMAGE}" "${BOARD}_corrupt_first_byte.bin"
offset=$(futility dump_fmap "${BOARD}_corrupt_first_byte.bin" EC_RW | \
  sed -n 's/area_offset: *//p')
dd if=/dev/random of="${BOARD}_corrupt_first_byte.bin" bs=1 \
  seek=$((offset+100)) count=1 conv=notrunc

echo "Generating image with bits corrupted at end of image:"
cp "${IMAGE}" "${BOARD}_corrupt_last_byte.bin"
offset=$(futility dump_fmap "${BOARD}_corrupt_last_byte.bin" SIG_RW | \
  sed -n 's/area_offset: *//p')
dd if=/dev/zero of="${BOARD}_corrupt_last_byte.bin" bs=1 \
  seek=$((offset-100)) count=1 conv=notrunc

# hexdumps are always nice to have to do diffs
for image in "${BOARD}.bin" "${BOARD}_corrupt_first_byte.bin" \
  "${BOARD}_corrupt_last_byte.bin" "${BOARD}.dev" "${BOARD}.dev.rb0" \
  "${BOARD}.dev.rb1" "${BOARD}.dev.rb9"; do
    xxd "${image}" > "${image}.hex"
done