From 1ee156fd00bb1d62dd527aa9b20631712a3c7485 Mon Sep 17 00:00:00 2001
From: Will Drewry <wad@chromium.org>
Date: Sat, 3 Jul 2010 13:27:19 -0500
Subject: [PATCH] [PATCH 3/5] Unify efi and legacy bootloader configuration
 generation

This change unifies the creation of extlinux.conf,
syslinux cfgs, and grub efi files.  It shouldn't change the
existing behavior but does add support for further arguments
and future use of syslinux (once it is properly rewritten by
an installer or other script).

TEST=in progress; manual run
BUG=chromium-os:327

Review URL: http://codereview.chromium.org/2829038
---
 build_image                           |  66 +++------
 create_legacy_bootloader_templates.sh | 203 ++++++++++++++++++++++++++
 2 files changed, 222 insertions(+), 47 deletions(-)
 create mode 100755 create_legacy_bootloader_templates.sh

diff --git a/build_image b/build_image
index 6fd3720b3e..c4f94dfe4e 100755
--- a/build_image
+++ b/build_image
@@ -403,33 +403,6 @@ create_base_image() {
   sudo tune2fs -L "${DISK_LABEL}" -U "${UUID}" -c 0 -i 0 "${OEM_LOOP_DEV}"
   sudo mount "${OEM_LOOP_DEV}" "${OEM_FS_DIR}"
 
-  # Turn root file system into bootable image.
-  if [[ "${ARCH}" = "x86" ]]; then
-    # Setup extlinux configuration.
-    # TODO: For some reason the /dev/disk/by-uuid is not being generated by udev
-    # in the initramfs. When we figure that out, switch to root=UUID=${UUID}.
-    sudo mkdir -p "${ROOT_FS_DIR}"/boot
-    # TODO(adlr): use initramfs for booting.
-    cat <<EOF | sudo dd of="${ROOT_FS_DIR}"/boot/extlinux.conf
-DEFAULT chromeos-usb
-PROMPT 0
-TIMEOUT 0
-
-label chromeos-usb
-  menu label chromeos-usb
-  kernel vmlinuz
-  append quiet console=tty2 init=/sbin/init boot=local rootwait root=/dev/sdb3 ro noresume noswap i915.modeset=1 loglevel=1 cros_legacy
-
-label chromeos-hd
-  menu label chromeos-hd
-  kernel vmlinuz
-  append quiet console=tty2 init=/sbin/init boot=local rootwait root=HDROOT ro noresume noswap i915.modeset=1 loglevel=1 cros_legacy
-EOF
-
-    # Make partition bootable and label it.
-    sudo extlinux -z --install "${ROOT_FS_DIR}/boot"
-  fi
-
   # -- Install packages into the root file system --
 
   # We need to install libc manually from the cross toolchain.
@@ -485,29 +458,28 @@ EOF
   fi
   sudo losetup "${ESP_LOOP_DEV}" "${ESP_FS_IMG}"
   sudo mount "${ESP_LOOP_DEV}" "${ESP_FS_DIR}"
-  sudo mkdir -p "${ESP_FS_DIR}/efi/boot"
-  sudo grub-mkimage -p /efi/boot -o "${ESP_FS_DIR}/efi/boot/bootx64.efi" \
-    part_gpt fat ext2 normal boot sh chain configfile linux
-  cat <<'EOF' | sudo dd of="${ESP_FS_DIR}/efi/boot/grub.cfg"
-set default=0
-set timeout=2
 
-# NOTE: These magic grub variables are a Chrome OS hack. They are not portable.
+  # Populates the root filesystem with legacy bootloader templates
+  # appropriate for the platform.  The autoupdater and installer will
+  # use those templates to update the legacy boot partition (12/ESP)
+  # on update.
+  # (This script does not populate vmlinuz.A and .B needed by syslinux.)
+  use_vboot=
+  ${SCRIPTS_DIR}/create_legacy_bootloader_templates.sh \
+    --arch=${ARCH} \
+    --to="${ROOT_FS_DIR}"/boot \
+    --install \
+    ${use_vboot}
 
-menuentry "local image A" {
-  linux $grubpartA/boot/vmlinuz quiet console=tty2 init=/sbin/init boot=local rootwait root=/dev/$linuxpartA ro noresume noswap i915.modeset=1 loglevel=1 cros_efi
-}
+  # Create a working copy so we don't need the rootfs mounted
+  sudo mkdir -p "${OUTPUT_DIR}"/boot
+  # This will include any built files dropped in /boot as well.
+  # Like the current vmlinuz.
+  sudo cp -r "${ROOT_FS_DIR}"/boot/. "${OUTPUT_DIR}"/boot/
 
-menuentry "local image B" {
-  linux $grubpartB/boot/vmlinuz quiet console=tty2 init=/sbin/init boot=local rootwait root=/dev/$linuxpartB ro noresume noswap i915.modeset=1 loglevel=1 cros_efi
-}
-
-menuentry "Alternate USB Boot" {
-  linux (hd0,3)/boot/vmlinuz quiet console=tty2 init=/sbin/init boot=local rootwait root=/dev/sdb3 ro noresume noswap i915.modeset=1 loglevel=1 cros_efi
-}
-
-EOF
-  # TODO(wad) add baseline syslinux files to ESP and install the syslinux loader
+  # Until bootloader management is unified, copy EFI in here.
+  sudo mkdir -p "${ESP_FS_IMG}"/efi
+  sudo cp -r "${ROOT_FS_DIR}"/boot/efi/. "${ESP_FS_IMG}"/efi
 
   # Builds the kernel partition image.  The temporary files are kept around
   # so that we can perform a load_kernel_test later on the final image.
diff --git a/create_legacy_bootloader_templates.sh b/create_legacy_bootloader_templates.sh
new file mode 100755
index 0000000000..e0f2bfcb01
--- /dev/null
+++ b/create_legacy_bootloader_templates.sh
@@ -0,0 +1,203 @@
+#!/bin/bash
+
+# Copyright (c) 2010 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.
+
+# Helper script that generates the signed kernel image
+
+. "$(dirname "$0")/common.sh"
+
+get_default_board
+
+# Flags.
+DEFINE_string arch "x86" \
+  "The boot architecture: arm or x86. (Default: x86)"
+# TODO(wad) once extlinux is dead, we can remove this.
+DEFINE_boolean install ${FLAGS_FALSE} \
+  "Controls whether extlinux is run on 'to'. (Default: false)"
+DEFINE_string to "/tmp/boot" \
+  "Path to populate with bootloader templates (Default: /tmp/boot)"
+DEFINE_string usb_disk /dev/sdb3 \
+  "Path syslinux should use to do a usb boot. Default: /dev/sdb3"
+DEFINE_string boot_args "" \
+  "Additional boot arguments to pass to the commandline (Default: '')"
+DEFINE_boolean use_vboot ${FLAGS_FALSE} \
+  "Controls whether the default boot targets are verified (Default: false)"
+DEFINE_integer vboot_error_behavior 2 \
+  "Verified boot error behavior [0: I/O errors, 1: reboot, 2: nothing] \
+(Default: 2)"
+DEFINE_integer vboot_max_ios 1024 \
+  "Optional number of outstanding I/O operations. (Default: 1024)"
+
+# Parse flags
+FLAGS "$@" || exit 1
+eval set -- "${FLAGS_ARGV}"
+set -e
+
+# Common kernel command-line args
+common_args="quiet console=tty2 init=/sbin/init boot=local rootwait ro noresume"
+common_args="${common_args} noswap loglevel=1"
+
+# Common verified boot command-line args
+vboot_common="dm_verity.error_behavior=${FLAGS_vboot_error_behavior}"
+vboot_common="${vboot_common} dm_verity.max_bios=${FLAGS_vboot_max_ios}"
+
+# Populate the x86 rootfs to support legacy and EFI bios config templates.
+# The templates are used by the installer to populate partition 12 with
+# the correct bootloader configuration.
+# While we transition to that model, extlinux.conf will still be used
+# on the root filesystem.
+if [[ "${FLAGS_arch}" == "x86" ]]; then
+  # Setup extlinux configuration.
+  # TODO: For some reason the /dev/disk/by-uuid is not being generated by udev
+  # in the initramfs. When we figure that out, switch to root=UUID=${UUID}.
+  sudo mkdir -p ${FLAGS_to}
+  # TODO(adlr): use initramfs for booting.
+    cat <<EOF | sudo dd of="${FLAGS_to}"/extlinux.conf 2>/dev/null
+DEFAULT chromeos-usb
+PROMPT 0
+TIMEOUT 0
+
+label chromeos-usb
+  menu label chromeos-usb
+  kernel vmlinuz
+  append ${common_args} root=/dev/sdb3 i915.modeset=1 cros_legacy
+
+label chromeos-hd
+  menu label chromeos-hd
+  kernel vmlinuz
+  append ${common_args} root=HDROOT i915.modeset=1 cros_legacy
+EOF
+
+  # Make partition bootable and label it.
+  # TODO(wad) remove this after we've transitioned everyone to syslinux.
+  if [[ ${FLAGS_install} -eq ${FLAGS_TRUE} ]]; then
+    sudo extlinux -z --install "${FLAGS_to}"
+  fi
+
+  # /boot/syslinux must be installed in partition 12 as /syslinux/.
+  SYSLINUX_DIR="${FLAGS_to}/syslinux"
+  sudo mkdir -p "${SYSLINUX_DIR}"
+
+  cat <<EOF | sudo dd of="${SYSLINUX_DIR}/syslinux.cfg" 2>/dev/null
+PROMPT 0
+TIMEOUT 0
+
+# the actual target
+include /syslinux/default.cfg
+
+# chromeos-usb.A
+include /syslinux/usb.A.cfg
+
+# chromeos-hd.A / chromeos-vhd.A
+include /syslinux/root.A.cfg
+
+# chromeos-hd.B / chromeos-vhd.B
+include /syslinux/root.B.cfg
+EOF
+  info "Emitted ${SYSLINUX_DIR}/syslinux.cfg"
+
+  if [[ ${FLAGS_use_vboot} -eq ${FLAGS_TRUE} ]]; then
+    # To change the active target, only this file needs to change.
+    cat <<EOF | sudo dd of="${SYSLINUX_DIR}/default.cfg" 2>/dev/null
+DEFAULT chromeos-vusb.A
+EOF
+  else
+      cat <<EOF | sudo dd of="${SYSLINUX_DIR}/default.cfg" 2>/dev/null
+DEFAULT chromeos-usb.A
+EOF
+  fi
+  info "Emitted ${SYSLINUX_DIR}/default.cfg"
+
+  cat <<EOF | sudo dd of="${SYSLINUX_DIR}/usb.A.cfg" 2>/dev/null
+label chromeos-usb.A
+  menu label chromeos-usb.A
+  kernel vmlinuz.A
+  append ${common_args} root=${FLAGS_usb_disk} i915.modeset=1 cros_legacy
+
+label chromeos-vusb.A
+  menu label chromeos-vusb.A
+  kernel vmlinuz.A
+  append ${common_args} ${vboot_common} root=/dev/dm-0 i915.modeset=1 cros_legacy dm="DMTABLEA"
+EOF
+  info "Emitted ${SYSLINUX_DIR}/usb.A.cfg"
+
+  # Different files are used so that the updater can only touch the file it
+  # needs to for a given change.  This will minimize any potential accidental
+  # updates issues, hopefully.
+  cat <<EOF | sudo dd of="${SYSLINUX_DIR}/root.A.cfg" 2>/dev/null
+label chromeos-hd.A
+  menu label chromeos-hd.A
+  kernel vmlinuz.A
+  append ${common_args} root=HDROOTA i915.modeset=1 cros_legacy
+
+label chromeos-vhd.A
+  menu label chromeos-vhd.A
+  kernel vmlinuz.A
+  append ${common_args} ${vboot_common} root=/dev/dm-0 i915.modeset=1 cros_legacy dm="DMTABLEA"
+EOF
+  info "Emitted ${SYSLINUX_DIR}/root.A.cfg"
+
+  cat <<EOF | sudo dd of="${SYSLINUX_DIR}/root.B.cfg" 2>/dev/null
+label chromeos-hd.B
+  menu label chromeos-hd.B
+  kernel vmlinuz.B
+  append ${common_args} root=HDROOTB i915.modeset=1 cros_legacy
+
+label chromeos-vhd.B
+  menu label chromeos-vhd.B
+  kernel vmlinuz.B
+  append ${common_args} ${vboot_common} root=/dev/dm-0 i915.modeset=1 cros_legacy dm="DMTABLEB"
+EOF
+  info "Emitted ${SYSLINUX_DIR}/root.B.cfg"
+
+  cat <<EOF | sudo dd of="${SYSLINUX_DIR}/README" 2>/dev/null
+Partition 12 contains the active bootloader configuration when
+booting from a non-Chrome OS BIOS.  EFI BIOSes use /efi/*
+and legacy BIOSes use this syslinux configuration.
+EOF
+  info "Emitted ${SYSLINUX_DIR}/README"
+
+  # To cover all of our bases, now populate templated boot support for efi.
+  sudo mkdir -p "${FLAGS_to}"/efi/boot
+  sudo grub-mkimage -p /efi/boot -o "${FLAGS_to}/efi/boot/bootx64.efi" \
+    part_gpt fat ext2 normal boot sh chain configfile linux
+  # Templated variables:
+  #  DMTABLEA, DMTABLEB -> '0 xxxx verity ... '
+  # This should be replaced during postinst when updating the ESP.
+  cat <<EOF | sudo dd of="${FLAGS_to}/efi/boot/grub.cfg" 2>/dev/null
+set default=0
+set timeout=2
+
+# NOTE: These magic grub variables are a Chrome OS hack. They are not portable.
+
+menuentry "local image A" {
+  linux \$grubpartA/boot/vmlinuz ${common_args} i915.modeset=1 cros_efi root=/dev/\$linuxpartA
+}
+
+menuentry "local image B" {
+  linux \$grubpartB/boot/vmlinuz ${common_args} i915.modeset=1 cros_efi root=/dev/\$linuxpartB
+}
+
+menuentry "verified image A" {
+  linux \$grubpartA/boot/vmlinuz ${common_args} ${vboot_common} i915.modeset=1 cros_efi root=/dev/dm-0 dm="DMTABLEA"
+}
+
+menuentry "verified image B" {
+  linux \$grubpartB/boot/vmlinuz ${common_args} ${vboot_common} i915.modeset=1 cros_efi root=/dev/dm-0 dm="DMTABLEB"
+}
+
+# FIXME: usb doesn't support verified boot for now
+menuentry "Alternate USB Boot" {
+  linux (hd0,3)/boot/vmlinuz ${common_args} root=/dev/sdb3 i915.modeset=1 cros_efi
+}
+EOF
+  if [[ ${FLAGS_use_vboot} -eq ${FLAGS_TRUE} ]]; then
+    sed -i -e 's/^set default=.*/set default=2/' "${FLAGS_to}/efi/boot/grub.cfg"
+  fi
+  info "Emitted ${FLAGS_to}/efi/boot/grub.cfg"
+  exit 0
+fi
+
+info "The target platform does not use bootloader templates."