image: T4516: Added system image tools

This commit adds the whole set of system image tools written from the scratch in
Python that allows performing all the operations on images:

* check information
* perform installation and deletion
* versions management

Also, it contains a new service that will update the GRUB menu and keep tracking
its version in the future.

WARNING: The commit contains non-reversible changes. Because of boot menu
changes, it will not be possible to manage images from older VyOS versions after
an update.

1 files changed, 557 insertions, 0 deletions

diff --git a/src/op_mode/image_installer.py b/src/op_mode/image_installer.py
new file mode 100644
index 000000000..6ebb38e46
--- /dev/null
+++ b/src/op_mode/image_installer.py
@@ -0,0 +1,557 @@
+#!/usr/bin/env python3
+#
+# Copyright 2022 VyOS maintainers and contributors <maintainers@vyos.io>
+#
+# This file is part of VyOS.
+#
+# VyOS is free software: you can redistribute it and/or modify it under the
+# terms of the GNU General Public License as published by the Free Software
+# Foundation, either version 3 of the License, or (at your option) any later
+# version.
+#
+# VyOS is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+# details.
+#
+# You should have received a copy of the GNU General Public License along with
+# VyOS. If not, see <https://www.gnu.org/licenses/>.
+
+from argparse import ArgumentParser, Namespace
+from pathlib import Path
+from shutil import copy, rmtree, copytree
+from sys import exit
+from urllib.parse import urlparse
+
+from psutil import disk_partitions
+
+from vyos.configtree import ConfigTree
+from vyos.remote import download
+from vyos.system import disk, grub, image
+from vyos.template import render
+from vyos.util import ask_input, ask_yes_no, run
+
+# define text messages
+MSG_ERR_NOT_LIVE: str = 'The system is already installed. Please use "add system image" instead.'
+MSG_ERR_LIVE: str = 'The system is in live-boot mode. Please use "install image" instead.'
+MSG_ERR_NO_DISK: str = 'No suitable disk was found. There must be at least one disk of 2GB or greater size.'
+MSG_INFO_INSTALL_WELCOME: str = 'Welcome to VyOS installation!\nThis command will install the VyOS to your permanent storage.'
+MSG_INFO_INSTALL_EXIT: str = 'Exitting from VyOS installation'
+MSG_INFO_INSTALL_SUCCESS: str = 'The image installed successfully'
+MSG_INFO_INSTALL_DISKS_LIST: str = 'Were found the next disks:'
+MSG_INFO_INSTALL_DISK_SELECT: str = 'Which one should be used for installation?'
+MSG_INFO_INSTALL_DISK_CONFIRM: str = 'Installation will delete all data on the drive. Continue?'
+MSG_INFO_INSTALL_PARTITONING: str = 'Creating partition table...'
+MSG_INPUT_CONFIG_FOUND: str = 'An active configuration was found. Would you like to copy it to the new image?'
+MSG_INPUT_IMAGE_NAME: str = 'What would you like to name this image?'
+MSG_INPUT_IMAGE_DEFAULT: str = 'Would you like to set a new image as default one for boot?'
+MSG_INPUT_PASSWORD: str = 'Please enter a password for the "vyos" user'
+MSG_INPUT_ROOT_SIZE_ALL: str = 'Would you like to use all free space on the drive?'
+MSG_INPUT_ROOT_SIZE_SET: str = 'What should be a size (in GB) of the root partition (min is 1.5 GB)?'
+MSG_INPUT_CONSOLE_TYPE: str = 'What console should be used by default? (K: KVM, S: Serial, U: USB-Serial)?'
+MSG_WARN_ISO_SIGN_INVALID: str = 'Signature is not valid. Do you want to continue with installation?'
+MSG_WARN_ISO_SIGN_UNAVAL: str = 'Signature is not available. Do you want to continue with installation?'
+MSG_WARN_ROOT_SIZE_TOOBIG: str = 'The size is too big. Try again.'
+MSG_WARN_ROOT_SIZE_TOOSMALL: str = 'The size is too small. Try again'
+MSG_WARN_IMAGE_NAME_WRONG: str = 'The suggested name is unsupported!\n'
+'It must be between 1 and 32 characters long and contains only the next characters: .+-_ a-z A-Z 0-9'
+CONST_MIN_DISK_SIZE: int = 2147483648  # 2 GB
+CONST_MIN_ROOT_SIZE: int = 1610612736  # 1.5 GB
+# a reserved space: 2MB for header, 1 MB for BIOS partition, 256 MB for EFI
+CONST_RESERVED_SPACE: int = (2 + 1 + 256) * 1024**2
+
+# define directories and paths
+DIR_INSTALLATION: str = '/mnt/installation'
+DIR_ROOTFS_SRC: str = f'{DIR_INSTALLATION}/root_src'
+DIR_ROOTFS_DST: str = f'{DIR_INSTALLATION}/root_dst'
+DIR_ISO_MOUNT: str = f'{DIR_INSTALLATION}/iso_src'
+DIR_DST_ROOT: str = f'{DIR_INSTALLATION}/disk_dst'
+DIR_KERNEL_SRC: str = '/boot/'
+FILE_ROOTFS_SRC: str = '/usr/lib/live/mount/medium/live/filesystem.squashfs'
+ISO_DOWNLOAD_PATH: str = '/tmp/vyos_installation.iso'
+
+# default boot variables
+DEFAULT_BOOT_VARS: dict[str, str] = {
+    'timeout': '5',
+    'console_type': 'tty',
+    'console_num': '0',
+    'bootmode': 'normal'
+}
+
+
+def bytes_to_gb(size: int) -> float:
+    """Convert Bytes to GBytes, rounded to 1 decimal number
+
+    Args:
+        size (int): input size in bytes
+
+    Returns:
+        float: size in GB
+    """
+    return round(size / 1024**3, 1)
+
+
+def gb_to_bytes(size: float) -> int:
+    """Convert GBytes to Bytes
+
+    Args:
+        size (float): input size in GBytes
+
+    Returns:
+        int: size in bytes
+    """
+    return int(size * 1024**3)
+
+
+def find_disk() -> tuple[str, int]:
+    """Find a target disk for installation
+
+    Returns:
+        tuple[str, int]: disk name and size in bytes
+    """
+    # check for available disks
+    disks_available: dict[str, int] = disk.disks_size()
+    for disk_name, disk_size in disks_available.copy().items():
+        if disk_size < CONST_MIN_DISK_SIZE:
+            del disks_available[disk_name]
+    if not disks_available:
+        print(MSG_ERR_NO_DISK)
+        exit(MSG_INFO_INSTALL_EXIT)
+
+    # select one as a target
+    print(MSG_INFO_INSTALL_DISKS_LIST)
+    default_disk: str = list(disks_available)[0]
+    for disk_name, disk_size in disks_available.items():
+        disk_size_human: str = bytes_to_gb(disk_size)
+        print(f'Drive: {disk_name} ({disk_size_human} GB)')
+    disk_selected: str = ask_input(MSG_INFO_INSTALL_DISK_SELECT,
+                                   default=default_disk,
+                                   valid_responses=list(disks_available))
+
+    return disk_selected, disks_available[disk_selected]
+
+
+def ask_root_size(available_space: int) -> int:
+    """Define a size of root partition
+
+    Args:
+        available_space (int): available space in bytes for a root partition
+
+    Returns:
+        int: defined size
+    """
+    if ask_yes_no(MSG_INPUT_ROOT_SIZE_ALL, default=True):
+        return available_space
+
+    while True:
+        root_size_gb: str = ask_input(MSG_INPUT_ROOT_SIZE_SET)
+        root_size_kbytes: int = (gb_to_bytes(float(root_size_gb))) // 1024
+
+        if root_size_kbytes > available_space:
+            print(MSG_WARN_ROOT_SIZE_TOOBIG)
+            continue
+        if root_size_kbytes < CONST_MIN_ROOT_SIZE / 1024:
+            print(MSG_WARN_ROOT_SIZE_TOOSMALL)
+            continue
+
+        return root_size_kbytes
+
+
+def prepare_tmp_disr() -> None:
+    """Create temporary directories for installation
+    """
+    print('Creating temporary directories')
+    for dir in [DIR_ROOTFS_SRC, DIR_ROOTFS_DST, DIR_DST_ROOT]:
+        dirpath = Path(dir)
+        dirpath.mkdir(mode=0o755, parents=True)
+
+
+def setup_grub(root_dir: str) -> None:
+    """Install GRUB configurations
+
+    Args:
+        root_dir (str): a path to the root of target filesystem
+    """
+    print('Installing GRUB configuration files')
+    grub_cfg_main = f'{root_dir}/{grub.GRUB_DIR_MAIN}/grub.cfg'
+    grub_cfg_vars = f'{root_dir}/{grub.CFG_VYOS_VARS}'
+    grub_cfg_modules = f'{root_dir}/{grub.CFG_VYOS_MODULES}'
+    grub_cfg_menu = f'{root_dir}/{grub.CFG_VYOS_MENU}'
+    grub_cfg_options = f'{root_dir}/{grub.CFG_VYOS_OPTIONS}'
+
+    # create new files
+    render(grub_cfg_main, grub.TMPL_GRUB_MAIN, {})
+    grub.common_write(root_dir)
+    grub.vars_write(grub_cfg_vars, DEFAULT_BOOT_VARS)
+    grub.modules_write(grub_cfg_modules, [])
+    grub.write_cfg_ver(1, root_dir)
+    render(grub_cfg_menu, grub.TMPL_GRUB_MENU, {})
+    render(grub_cfg_options, grub.TMPL_GRUB_OPTS, {})
+
+
+def configure_authentication(config_file: str, password: str) -> None:
+    config = ConfigTree(config_file)
+    config.set([
+        'system', 'login', 'user', 'vyos', 'authentication',
+        'plaintext-password'
+    ],
+               value=password,
+               replace=True)
+    config.set_tag(['system', 'login', 'user'])
+
+
+def validate_signature(file_path: str, sign_type: str) -> None:
+    """Validate a file by signature and delete a signature file
+
+    Args:
+        file_path (str): a path to file
+        sign_type (str): a signature type
+    """
+    print('Validating signature')
+    signature_valid: bool = False
+    # validate with minisig
+    if sign_type == 'minisig':
+        for pubkey in [
+                '/usr/share/vyos/keys/vyos-release.minisign.pub',
+                '/usr/share/vyos/keys/vyos-backup.minisign.pub'
+        ]:
+            if run(f'minisign -V -q -p {pubkey} -m {file_path} -x {file_path}.minisig'
+                  ) == 0:
+                signature_valid = True
+                break
+        Path(f'{file_path}.minisig').unlink()
+    # validate with GPG
+    if sign_type == 'asc':
+        if run(f'gpg --verify ${file_path}.asc ${file_path}') == 0:
+            signature_valid = True
+        Path(f'{file_path}.asc').unlink()
+
+    # warn or pass
+    if not signature_valid:
+        if not ask_yes_no(MSG_WARN_ISO_SIGN_INVALID, default=False):
+            exit(MSG_INFO_INSTALL_EXIT)
+    else:
+        print('Signature is valid')
+
+
+def image_fetch(image_path: str) -> Path:
+    """Fetch an ISO image
+
+    Args:
+        image_path (str): a path, remote or local
+
+    Returns:
+        Path: a path to a local file
+    """
+    try:
+        # check a type of path
+        if urlparse(image_path).scheme:
+            # download an image
+            download(ISO_DOWNLOAD_PATH, image_path, True, True)
+            # download a signature
+            sign_file = (False, '')
+            for sign_type in ['minisig', 'asc']:
+                try:
+                    download(f'{ISO_DOWNLOAD_PATH}.{sign_type}',
+                             f'{image_path}.{sign_type}')
+                    sign_file = (True, sign_type)
+                    break
+                except Exception:
+                    print(f'{sign_type} signature is not available')
+            # validate a signature if it is available
+            if sign_file[0]:
+                validate_signature(ISO_DOWNLOAD_PATH, sign_file[1])
+            else:
+                if not ask_yes_no(MSG_WARN_ISO_SIGN_UNAVAL, default=False):
+                    cleanup()
+                    exit(MSG_INFO_INSTALL_EXIT)
+
+            return Path(ISO_DOWNLOAD_PATH)
+        else:
+            local_path: Path = Path(image_path)
+            if local_path.is_file():
+                return local_path
+            else:
+                raise
+    except Exception:
+        print(f'The image cannot be fetched from: {image_path}')
+        exit(1)
+
+
+def migrate_config() -> bool:
+    """Check for active config and ask user for migration
+
+    Returns:
+        bool: user's decision
+    """
+    active_config_path: Path = Path('/opt/vyatta/etc/config/config.boot')
+    if active_config_path.exists():
+        if ask_yes_no(MSG_INPUT_CONFIG_FOUND, default=True):
+            return True
+    return False
+
+
+def cleanup(mounts: list[str] = [], remove_items: list[str] = []) -> None:
+    """Clean up after installation
+
+    Args:
+        mounts (list[str], optional): List of mounts to unmount.
+        Defaults to [].
+        remove_items (list[str], optional): List of files or directories
+        to remove. Defaults to [].
+    """
+    print('Cleaning up')
+    # clean up installation directory by default
+    mounts_all = disk_partitions(all=True)
+    for mounted_device in mounts_all:
+        if mounted_device.mountpoint.startswith(DIR_INSTALLATION) and not (
+                mounted_device.device in mounts or
+                mounted_device.mountpoint in mounts):
+            mounts.append(mounted_device.mountpoint)
+    # add installation dir to cleanup list
+    if DIR_INSTALLATION not in remove_items:
+        remove_items.append(DIR_INSTALLATION)
+    # also delete an ISO file
+    if Path(ISO_DOWNLOAD_PATH).exists(
+    ) and ISO_DOWNLOAD_PATH not in remove_items:
+        remove_items.append(ISO_DOWNLOAD_PATH)
+
+    if mounts:
+        print('Unmounting target filesystems')
+        for mountpoint in mounts:
+            disk.partition_umount(mountpoint)
+    if remove_items:
+        print('Removing temporary files')
+        for remove_item in remove_items:
+            if Path(remove_item).exists():
+                if Path(remove_item).is_file():
+                    Path(remove_item).unlink()
+                if Path(remove_item).is_dir():
+                    rmtree(remove_item)
+
+
+def install_image() -> None:
+    """Install an image to a disk
+    """
+    if not image.is_live_boot():
+        exit(MSG_ERR_NOT_LIVE)
+
+    print(MSG_INFO_INSTALL_WELCOME)
+    if not ask_yes_no('Would you like to continue?'):
+        print(MSG_INFO_INSTALL_EXIT)
+        exit()
+
+    try:
+        # configure image name
+        running_image_name: str = image.get_running_image()
+        while True:
+            image_name: str = ask_input(MSG_INPUT_IMAGE_NAME,
+                                        running_image_name)
+            if image.validate_name(image_name):
+                break
+            print(MSG_WARN_IMAGE_NAME_WRONG)
+
+        # define target drive
+        install_target, target_size = find_disk()
+
+        # define target rootfs size in KB (smallest unit acceptable by sgdisk)
+        availabe_size: int = (target_size - CONST_RESERVED_SPACE) // 1024
+        rootfs_size: int = ask_root_size(availabe_size)
+
+        # ask for password
+        user_password: str = ask_input(MSG_INPUT_PASSWORD, default='vyos')
+
+        # ask for default console
+        console_type: str = ask_input(MSG_INPUT_CONSOLE_TYPE,
+                                      default='K',
+                                      valid_responses=['K', 'S', 'U'])
+        console_dict: dict[str, str] = {'K': 'tty', 'S': 'ttyS', 'U': 'ttyUSB'}
+
+        # create partitions
+        if not ask_yes_no(MSG_INFO_INSTALL_DISK_CONFIRM):
+            print(MSG_INFO_INSTALL_EXIT)
+            exit()
+        print(MSG_INFO_INSTALL_PARTITONING)
+        disk.disk_cleanup(install_target)
+        disk.parttable_create(install_target, rootfs_size)
+        disk.filesystem_create(f'{install_target}2', 'efi')
+        disk.filesystem_create(f'{install_target}3', 'ext4')
+
+        # create directiroes for installation media
+        prepare_tmp_disr()
+
+        # mount target filesystem and create required dirs inside
+        print('Mounting new partitions')
+        disk.partition_mount(f'{install_target}3', DIR_DST_ROOT)
+        Path(f'{DIR_DST_ROOT}/boot/efi').mkdir(parents=True)
+        disk.partition_mount(f'{install_target}2', f'{DIR_DST_ROOT}/boot/efi')
+
+        # a config dir. It is the deepest one, so the comand will
+        # create all the rest in a single step
+        print('Creating a configuration file')
+        target_config_dir: str = f'{DIR_DST_ROOT}/boot/{image_name}/rw/opt/vyatta/etc/config/'
+        Path(target_config_dir).mkdir(parents=True)
+        # copy config
+        if migrate_config():
+            copy('/opt/vyatta/etc/config/config.boot', target_config_dir)
+        else:
+            copy('/opt/vyatta/etc/config.boot.default',
+                 f'{target_config_dir}/config.boot')
+        configure_authentication(f'{target_config_dir}/config.boot',
+                                 user_password)
+        Path(f'{target_config_dir}/.vyatta_config').touch()
+
+        # create a persistence.conf
+        Path(f'{DIR_DST_ROOT}/persistence.conf').write_text('/ union\n')
+
+        # copy system image and kernel files
+        print('Copying system image files')
+        for file in Path(DIR_KERNEL_SRC).iterdir():
+            if file.is_file():
+                copy(file, f'{DIR_DST_ROOT}/boot/{image_name}/')
+        copy(FILE_ROOTFS_SRC,
+             f'{DIR_DST_ROOT}/boot/{image_name}/{image_name}.squashfs')
+
+        # install GRUB
+        print('Installing GRUB to the drive')
+        grub.install(install_target, f'{DIR_DST_ROOT}/boot/',
+                     f'{DIR_DST_ROOT}/boot/efi')
+        setup_grub(DIR_DST_ROOT)
+        # add information about version
+        grub.create_structure()
+        grub.version_add(image_name, DIR_DST_ROOT)
+        grub.set_default(image_name, DIR_DST_ROOT)
+        grub.set_console_type(console_dict[console_type], DIR_DST_ROOT)
+
+        # umount filesystems and remove temporary files
+        cleanup([f'{install_target}2', f'{install_target}3'],
+                ['/mnt/installation'])
+
+        # we are done
+        print(MSG_INFO_INSTALL_SUCCESS)
+        exit()
+
+    except Exception as err:
+        print(f'Unable to install VyOS: {err}')
+        # unmount filesystems and clenup
+        try:
+            cleanup([f'{install_target}2', f'{install_target}3'],
+                    ['/mnt/installation'])
+        except Exception as err:
+            print(f'Cleanup failed: {err}')
+
+        exit(1)
+
+
+def add_image(image_path: str) -> None:
+    """Add a new image
+
+    Args:
+        image_path (str): a path to an ISO image
+    """
+    if image.is_live_boot():
+        exit(MSG_ERR_LIVE)
+
+    # fetch an image
+    iso_path: Path = image_fetch(image_path)
+    try:
+        # mount an ISO
+        Path(DIR_ISO_MOUNT).mkdir(mode=0o755, parents=True)
+        disk.partition_mount(iso_path, DIR_ISO_MOUNT, 'iso9660')
+
+        # check sums
+        print('Validating image checksums')
+        if run(f'cd {DIR_ISO_MOUNT} && sha256sum --status -c sha256sum.txt'):
+            cleanup()
+            exit('Image checksum verification failed.')
+
+        # mount rootfs (to get a system version)
+        Path(DIR_ROOTFS_SRC).mkdir(mode=0o755, parents=True)
+        disk.partition_mount(f'{DIR_ISO_MOUNT}/live/filesystem.squashfs',
+                             DIR_ROOTFS_SRC, 'squashfs')
+        version_file: str = Path(
+            f'{DIR_ROOTFS_SRC}/opt/vyatta/etc/version').read_text()
+        disk.partition_umount(f'{DIR_ISO_MOUNT}/live/filesystem.squashfs')
+        version_name: str = version_file.lstrip('Version: ').strip()
+        image_name: str = ask_input(MSG_INPUT_IMAGE_NAME, version_name)
+        set_as_default: bool = ask_yes_no(MSG_INPUT_IMAGE_DEFAULT, default=True)
+
+        # find target directory
+        root_dir: str = disk.find_persistence()
+
+        # a config dir. It is the deepest one, so the comand will
+        # create all the rest in a single step
+        target_config_dir: str = f'{root_dir}/boot/{image_name}/rw/opt/vyatta/etc/config/'
+        # copy config
+        if migrate_config():
+            print('Copying configuration directory')
+            copytree('/opt/vyatta/etc/config/', target_config_dir)
+        else:
+            Path(target_config_dir).mkdir(parents=True)
+            Path(f'{target_config_dir}/.vyatta_config').touch()
+
+        # copy system image and kernel files
+        print('Copying system image files')
+        for file in Path(f'{DIR_ISO_MOUNT}/live').iterdir():
+            if file.is_file() and (file.match('initrd*') or
+                                   file.match('vmlinuz*')):
+                copy(file, f'{root_dir}/boot/{image_name}/')
+        copy(f'{DIR_ISO_MOUNT}/live/filesystem.squashfs',
+             f'{root_dir}/boot/{image_name}/{image_name}.squashfs')
+
+        # unmount an ISO and cleanup
+        cleanup([str(iso_path)])
+
+        # add information about version
+        grub.version_add(image_name, root_dir)
+        if set_as_default:
+            grub.set_default(image_name, root_dir)
+
+    except Exception as err:
+        # unmount an ISO and cleanup
+        cleanup([str(iso_path)])
+        exit(f'Whooops: {err}')
+
+
+def parse_arguments() -> Namespace:
+    """Parse arguments
+
+    Returns:
+        Namespace: a namespace with parsed arguments
+    """
+    parser: ArgumentParser = ArgumentParser(
+        description='Install new system images')
+    parser.add_argument('--action',
+                        choices=['install', 'add'],
+                        required=True,
+                        help='action to perform with an image')
+    parser.add_argument(
+        '--image_path',
+        help='a path (HTTP or local file) to an image that needs to be installed'
+    )
+    # parser.add_argument('--image_new_name', help='a new name for image')
+    args: Namespace = parser.parse_args()
+    # Validate arguments
+    if args.action == 'add' and not args.image_path:
+        exit('A path to image is required for add action')
+
+    return args
+
+
+if __name__ == '__main__':
+    try:
+        args: Namespace = parse_arguments()
+        if args.action == 'install':
+            install_image()
+        if args.action == 'add':
+            add_image(args.image_path)
+
+        exit()
+
+    except KeyboardInterrupt:
+        print('Stopped by Ctrl+C')
+        cleanup()
+        exit()
+
+    except Exception as err:
+        exit(f'{err}')