aboutsummaryrefslogtreecommitdiff
path: root/bootstrap
blob: 7aec0f92c8401adc7232f4ddb5f1b6b5f50107b3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
#! /usr/bin/env bash

# Bootstrap build2 Build OS.
#
# Assumptions/expectations:
#
# - host debootstrap/debian-archive-keyring matching release
#
# - /btrfs/<user> is a btrfs directory where the current user can create
#   snapshots
#
# - sudo is passwordless (used to run debootstrap, systemd-nspawn, etc)
#
# Options:
#
# --stage <num>
#   Jump straigh to stage <num> by clonning the previous stage snapshot.
#   Stages are:
#
#   1 - bootstrap phase 1
#   2 - bootstrap phase 2
#   3 - kernel build
#   4 - setup
#   5 - create footfs
#   6 - create kernel image and initrd
#
usage="usage: $0"

macaddr="de:ad:be:ef:b8:da" # @@ TMP mac address for testing.

id="$(id -un)"
btrfs=/btrfs
root="$btrfs/$id/buildos"

# Source distribution and packages. Base packages are installed on stage 1 via
# debootstrap. Extra packages are added on stage 4 via apt-get install. The
# idea is to be able to add extra packages without upgrading the base system.
# When we do upgrade the base system we normally move the extras to base.
#
# Notes:
#
#  - some packages (such as CPU microcode updates) are in non-free.
#  - systemd-container seems to be required by host systemd-nspawn.
#  - not installing linux-image-amd64 since building custom below
#
release="testing"
components="main,contrib,non-free"
mirror="http://deb.debian.org/debian/"
#mirror="https://deb.debian.org/debian/"

base_pkgs="locales,klibc-utils,sudo,systemd-container,udev"
base_pkgs+=",kmod,linux-base,firmware-linux-free,irqbalance"
base_pkgs+=",intel-microcode,amd64-microcode"
base_pkgs+=",pciutils,usbutils,dmidecode,cpuid"
base_pkgs+=",hdparm,btrfs-progs"
base_pkgs+=",lm-sensors,smartmontools"

base_pkgs+=",psmisc"
base_pkgs+=",net-tools,iproute2,iptables,isc-dhcp-client"
base_pkgs+=",ifupdown,bridge-utils,dnsmasq,ntp,postfix"
base_pkgs+=",iputils-ping,wget,curl,ca-certificates"
base_pkgs+=",openssh-client,openssh-server"
base_pkgs+=",tftp-hpa,tftpd-hpa"

base_pkgs+=",bzip2,xz-utils"
base_pkgs+=",less,nano,time"

base_pkgs+=",qemu-kvm,qemu-utils,socat"

base_pkgs+=",g++,make,pkg-config"

extra_pkgs="linux-cpupower"

owd="$(pwd)"
trap "{ cd '$owd'; exit 1; }" ERR
set -o errtrace # Trap in functions.

function info () { echo "$*" 1>&2; }
function error () { info "$*"; exit 1; }

stage="1"
stage_max="6"

while [ "$#" -gt 0 ]; do
  case "$1" in
    --stage)
      shift
      stage="$1"
      shift
      ;;
    -*)
      error "unknown option: $1"
      ;;
    *)
      break
      ;;
  esac
done

if [ "$stage" -lt "1" -o "$stage" -gt "$stage_max" ]; then
  error "invalid stage number $stage"
fi

# Extract version.
#
version="$(sed -n -re 's/^version: ([0-9]+\.[0-9]+\.[0-9]+).*$/\1/p' ./manifest)"
version_id="$(sed -n -re 's/^([0-9]+\.[0-9]+)\.[0-9]+$/\1/p' <<<"$version")"
if [ -z "$version" -o -z "$version_id" ]; then
  error "unable to extract version from manifest"
fi

# Btrfs subvolume manipulation.
#
function subvol_delete () # <path>
{
  # The subvol show (just as list) needs root.
  #
  if sudo btrfs subvol show "$1" 1>/dev/null 2>&1; then
    btrfs property set -ts "$1" ro false
    btrfs subvol delete "$1"
  fi
}

function subvol_create () # <path>
{
  btrfs subvol create "$@"
}

function subvol_snapshot () # [-r] <src-path> <dst-path>
{
  btrfs subvol snapshot "$@"
}

# Clean up the working subvolume and all the snapshots starting from the
# requested stage. Also, if stage is not 1, then restore the working subvolume
# from the previous stage snapshot.
#
subvol_delete "$root"

for i in $(seq "$stage" "$stage_max"); do
  subvol_delete "$root-$i"
done

if [ "$stage" -gt "1" ]; then
  i="$(($stage - 1))"
  info "restoring working subvolume from stage $i snapshot"
  subvol_snapshot "$root-$i" "$root"
fi

# Spawn a systemd namespace container (systemd-nspawn)
#
function nspawn () # <root> <systemd-nspawn-args>
{
  local r="$1"
  shift

  sudo systemd-nspawn --register=no -D "$r" "$@"

  # systemd-nspawn may create the /var/lib/machines subvolume which prevents
  # the deletion of the containing submodule. So we clean it up.
  #
  if sudo btrfs subvol show "$r/var/lib/machines" 1>/dev/null 2>&1; then
    sudo btrfs subvol delete "$r/var/lib/machines"
  fi
}

# (Over)write or append to a file in the installation root, for example:
#
# write <<<'localhost' /etc/hostname
#
function write () # <path> [<root>]
{
  local r="$2"
  if [ -z "$r" ]; then
    r="$root"
  fi

  sudo tee "$r$1" >/dev/null
}

function append () # <path> [<root>]
{
  local r="$2"
  if [ -z "$r" ]; then
    r="$root"
  fi

  sudo tee -a "$r$1" >/dev/null
}

# Stage 1: debootstrap, phase 1.
#
if [ "$stage" -eq "1" ]; then

  subvol_create "$root"

  sudo debootstrap \
    --foreign \
    --arch=amd64 \
    --merged-usr \
    --variant=minbase \
    --components="$components" \
    --include="$base_pkgs" \
    "$release" "$root" "$mirror"

  # Post-phase 1 fixups.
  #

  # Set the initial hostname to 'localhost'. This value is detected and
  # overriden by /sbin/dhclient-script if the DHCP server sends host-name.
  #
  write <<<'localhost' /etc/hostname

  # Set timezone to UTC (picked up by tzdata package during stage 2).
  #
  write <<<'Etc/UTC' /etc/timezone

  subvol_snapshot -r "$root" "$root-1"
fi

# Stage 2: debootstrap, phase 2.
#
if [ "$stage" -le "2" ]; then

  # Create a bootstrap script that will finish the bootstrap from within the
  # installation via systemd-nspawn.
  #
  sudo mkdir "$root/bootstrap"

  write <<EOF /bootstrap/bootstrap
#!/bin/bash

trap "exit 1" ERR
set -x

# Hack around systemd bug#79306 (changes /etc/localtime) by removing it now
# and making readonly below.
#
rm /etc/localtime

# Both nspawn and debootstrap try to mount /proc /sys (Debian bug#840372).
#
mkdir /tmp/proc /tmp/sys
mount --move /proc /tmp/proc
mount --move /sys /tmp/sys

# Run second stage of debootstrap.
#
if ! /debootstrap/debootstrap --second-stage; then
  cat /debootstrap/debootstrap.log 1>&2
  bash
  exit 1
fi

rm -f /etc/localtime
cp /usr/share/zoneinfo/UTC /etc/localtime
chattr +i /etc/localtime

# Change /etc/os-release, /etc/issue, /etc/motd.
#
cat <<EOF1 >/etc/os-release
NAME="Build OS"
VERSION="$version"
ID=buildos
ID_LIKE=debian
PRETTY_NAME="Build OS $version (Based on Debian)"
VERSION_ID="$version_id"
HOME_URL="https://build2.org/"
SUPPORT_URL="https://lists.build2.org/"
BUG_REPORT_URL="https://lists.build2.org/"
EOF1

cat <<EOF1 >/etc/issue
Build OS $version (Based on Debian) \n \l

EOF1

cat <<EOF1 >/etc/motd

Welcome to Build OS $version (https://build2.org)!

EOF1

# Make root login passwordless (we disable SSH root login in init).
#
passwd -d root

# Enable IPv4 forwarding (used for private bridge NAT).
#
sed -i -e 's/^# *\(net.ipv4.ip_forward\).*/\1=1/' /etc/sysctl.conf

# Setup locale. We only support en_US.UTF-8.
#
sed -i -e 's/^# *\(en_US.UTF-8\)/\1/' /etc/locale.gen
locale-gen --purge

cat <<EOF1 >/etc/default/locale
LANG="en_US.UTF-8"
LANGUAGE="en_US:en"
EOF1

EOF
  sudo chmod u+x "$root/bootstrap/bootstrap"

  # Notes:
  #
  # - Failed to create directory .../sys/fs/selinux: Read-only file system is
  #   harmless and fixed upstream (systemd issue#3748).
  #
  nspawn "$root" /bootstrap/bootstrap

  subvol_snapshot -r "$root" "$root-2"
fi

# Stage 3: kernel build.
#
if [ "$stage" -le "3" ]; then

  # Create the setup service that will be used by both this stage and the
  # setup stage below. Note that we will do actual building (which requires
  # installing extra packages) in a snapshot on the side.
  #
  sudo mkdir -p "$root/bootstrap"

  # Note that when started via systemd-nspawn, we get /dev/console, not
  # /dev/tty0.
  #
  write <<EOF /usr/lib/systemd/system/buildos-setup.service
[Unit]
Description=build os setup
After=multi-user.target
Conflicts=console-getty.service

[Service]
Type=idle
TimeoutStartSec=infinity
RemainAfterExit=true
ExecStart=/bootstrap/setup
StandardInput=tty-force
StandardOutput=inherit
StandardError=inherit
TTYPath=/dev/console
TTYReset=yes
TTYVHangup=yes

[Install]
WantedBy=multi-user.target
EOF

  sudo mkdir -p "$root/etc/systemd/system/multi-user.target.wants"
  sudo ln -sf "$root/usr/lib/systemd/system/buildos-setup.service" \
    "$root/etc/systemd/system/multi-user.target.wants/buildos-setup.service"

  # Create the kernel build snapshot, write the script that does the build
  # from within the installation and boot it up via systemd-nspawn --boot.
  #
  # Add this line before shutdown if need to debug/check things.
  #
  # setsid /bin/bash -c "exec /bin/bash -i <>/dev/console 1>&0 2>&1"
  #
  subvol_delete "$root-3-kernel"
  subvol_snapshot "$root" "$root-3-kernel"

  write <<EOF /bootstrap/setup "$root-3-kernel"
#!/bin/bash

trap "exit 1" ERR
set -x

# This seems to be the simplest method of building the standard Debian
# kernel with adjusted configuration. Taken from the Debian Kernel Handbook.
#
apt-get update
apt-get install -y build-essential linux-source
apt-get install -y bison flex
apt-get install -y libelf-dev
apt-get install -y libssl-dev
cd /usr/src
tar xf linux-source-*
mv linux-source-*/ linux
xzcat linux-config-*/config.amd64_none_amd64.xz >linux/.config
cd linux

# Adjust configuration.
#
echo 'CONFIG_SYSTEM_TRUSTED_KEYS=""' >>.config
echo 'CONFIG_BUILD_SALT=""'          >>.config
echo 'CONFIG_MODULE_SIG=n'           >>.config

# Adjust kernel command line size limit.
#
sed -i -re 's/^(#define COMMAND_LINE_SIZE ).+\$/\1 4096/' arch/x86/include/asm/setup.h
make oldconfig
scripts/config --disable DEBUG_INFO

make clean
make deb-pkg LOCALVERSION=-buildos KDEB_PKGVERSION=1 -j 8

# Clean up and shutdown.
#
rm /bootstrap/setup
systemctl poweroff

EOF
  sudo chmod u+x "$root-3-kernel/bootstrap/setup"

  nspawn "$root-3-kernel" --boot

  # Copy the kernel over and install it.
  #
  sudo cp "$root-3-kernel/usr/src/linux-image-"*.deb "$root/usr/src/"

  write <<EOF /bootstrap/setup
#!/bin/bash

trap "exit 1" ERR
set -x

dpkg -i /usr/src/linux-image-*.deb
rm -rf /usr/src/*
cd /
ln -s boot/vmlinuz-* /vmlinuz

# Clean up and shutdown.
#
rm /bootstrap/setup
systemctl poweroff

EOF
  sudo chmod u+x "$root/bootstrap/setup"

  nspawn "$root" --boot

  subvol_snapshot -r "$root" "$root-3"
fi

# Stage 4: setup.
#
if [ "$stage" -le "4" ]; then

  # Write the setup script that will finish the setup (the service is already
  # there from stage 3).
  #
  write <<EOF /bootstrap/setup
#!/bin/bash

trap "exit 1" ERR
set -x

# Install extra packages.
#
apt-get update
for p in \$(sed -e 's/,/ /g' <<<"$extra_pkgs"); do
  apt-get install -y --no-install-recommends "\$p"
done

# We want the utility (smartctl) but not the daemon.
#
systemctl disable smartd

# Create the build user, /build home directory. Make a password-less sudo'er.
#
# Note that we force UID/GID to specific numbers to make sure they are
# consistent across builds.
#
addgroup --gid 2000 build
adduser --uid 2000 --gid 2000 --home /build --gecos "" --disabled-password build
adduser build kvm
echo "build ALL=(ALL) NOPASSWD:ALL" >/etc/sudoers.d/build
echo "Defaults:build !syslog" >>/etc/sudoers.d/build
chmod 0440 /etc/sudoers.d/build

# Clean up package cache.
#
apt-get clean

# Clean up /bootstrap.
#
rm /etc/systemd/system/multi-user.target.wants/buildos-setup.service
rm /usr/lib/systemd/system/buildos-setup.service
rm -r /bootstrap

# Shutdown.
#
systemctl poweroff

EOF
  sudo chmod u+x "$root/bootstrap/setup"

  nspawn "$root" --boot

  subvol_snapshot -r "$root" "$root-4"
fi

# Stage 5: generate rootfs.
#
if [ "$stage" -le "5" ]; then

  # Note that there is also initramfs image that is embedded into kernel. In
  # Debian it contains just /dev/console and /root/.
  #
  # Quite a few files/directories are only accessible by root (e.g., /root) so
  # we run under sudo.
  #
  root_dirs="build dev etc mnt root usr var"
  root_links="bin sbin lib lib32 lib64"

  info "generating buildos-rootfs.cpio.gz..."

  cd "$root"
  sudo find $root_dirs $root_links -print0 | \
    sudo cpio --null -o -H newc | \
    gzip -9 > "$owd/buildos-rootfs.cpio.gz"
  cd "$owd"

  subvol_snapshot -r "$root" "$root-5"
fi

# Stage 6: generate initrd.
#
if [ "$stage" -le "6" ]; then

  # Generate buildid and store it in /etc/os-release and in buildos-buildid.
  # These are used by the monitor to detect when it's time to reboot.
  #
  # Note that /etc/os-release is a symlink to /usr/lib/os-release.
  #
  buildid="$(uuidgen)"

  sudo tee -a "$root/etc/os-release" >/dev/null <<<"BUILD_ID=\"$buildid\""

  # Install init and buildos monitor.
  #
  sudo install -m 755 ./init "$root/"
  sudo install -m 755 ./buildos "$root/usr/sbin/"
  sudo install -m 644 ./buildos.service "$root/usr/lib/systemd/system/"
  sudo ln -sf "$root/usr/lib/systemd/system/buildos.service" \
    "$root/etc/systemd/system/multi-user.target.wants/buildos.service"

  info "generating buildos-init.cpio.gz..."

  cd "$root"
  sudo cpio -o -H newc <<EOF | \
    gzip -9 > "$owd/buildos-init.cpio.gz"
usr/lib/os-release
init
usr/sbin/buildos
usr/lib/systemd/system/buildos.service
etc/systemd/system/multi-user.target.wants/buildos.service
EOF
  cd "$owd"

  cat buildos-rootfs.cpio.gz buildos-init.cpio.gz >buildos-initrd

  # Copy the kernel image next to the initramfs for convenience.
  #
  cp "$root/vmlinuz" buildos-image
  echo "$buildid" >buildos-buildid

  subvol_snapshot -r "$root" "$root-6"
fi

exit 0

# Test.
#
if [ ! -e /tmp/buildos-state ]; then
  qemu-img create -f raw /tmp/buildos-state 20M
fi

if [ ! -e /tmp/buildos-machines ]; then
  qemu-img create -f raw /tmp/buildos-machines 100M
fi

# To test PXE boot, replace -kernel/-initrd/-append with '-boot n'.
#
sudo kvm \
  -m 16G \
  -cpu host -smp "sockets=1,cores=4,threads=2" \
  -device "e1000,netdev=net0,mac=$macaddr" \
  -netdev "tap,id=net0,script=./qemu-ifup" \
  -device "virtio-scsi-pci,id=scsi" \
  -device "scsi-hd,drive=disk1" \
  -drive  "if=none,id=disk1,file=/tmp/buildos-state,format=raw" \
  -device "scsi-hd,drive=disk2" \
  -drive  "if=none,id=disk2,file=/tmp/buildos-machines,format=raw" \
  -boot n

#  -kernel buildos-image -initrd buildos-initrd \
#  -append "buildos.smtp_relay=build2.org buildos.admin_email=admin@build2.org"