diff options
Diffstat (limited to 'src/system/grub_update.py')
-rw-r--r-- | src/system/grub_update.py | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/src/system/grub_update.py b/src/system/grub_update.py new file mode 100644 index 000000000..ebdc73af0 --- /dev/null +++ b/src/system/grub_update.py @@ -0,0 +1,211 @@ +#!/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 pathlib import Path +from re import compile, MULTILINE, DOTALL +from sys import exit + +from vyos.system import disk, grub, image +from vyos.template import render + +# define configuration version +CFG_VER = 1 + +# define regexes and variables +REGEX_VERSION = r'^menuentry "[^\n]*{\n[^}]*\s+linux /boot/(?P<version>\S+)/[^}]*}' +REGEX_MENUENTRY = r'^menuentry "[^\n]*{\n[^}]*\s+linux /boot/(?P<version>\S+)/vmlinuz (?P<options>[^\n]+)\n[^}]*}' +REGEX_CONSOLE = r'^.*console=(?P<console_type>[^\s\d]+)(?P<console_num>[\d]+).*$' +REGEX_SANIT_CONSOLE = r'\ ?console=[^\s\d]+[\d]+(,\d+)?\ ?' +REGEX_SANIT_INIT = r'\ ?init=\S*\ ?' +PW_RESET_OPTION = 'init=/opt/vyatta/sbin/standalone_root_pw_reset' + + +def cfg_check_update() -> bool: + """Check if GRUB structure update is required + + Returns: + bool: False if not required, True if required + """ + current_ver = grub.get_cfg_ver() + if current_ver and current_ver >= CFG_VER: + return False + else: + return True + + +def find_versions(menu_entries: list) -> list: + """Find unique VyOS versions from menu entries + + Args: + menu_entries (list): a list with menu entries + + Returns: + list: List of installed versions + """ + versions = [] + for vyos_ver in menu_entries: + versions.append(vyos_ver.get('version')) + # remove duplicates + versions = list(set(versions)) + return versions + + +def filter_unparsed(grub_path: str) -> str: + """Find currently installed VyOS version + + Args: + grub_path (str): a path to the grub.cfg file + + Returns: + str: unparsed grub.cfg items + """ + config_text = Path(grub_path).read_text() + regex_filter = compile(REGEX_VERSION, MULTILINE | DOTALL) + filtered = regex_filter.sub('', config_text) + regex_filter = compile(grub.REGEX_GRUB_VARS, MULTILINE) + filtered = regex_filter.sub('', filtered) + regex_filter = compile(grub.REGEX_GRUB_MODULES, MULTILINE) + filtered = regex_filter.sub('', filtered) + # strip extra new lines + filtered = filtered.strip() + return filtered + + +def sanitize_boot_opts(boot_opts: str) -> str: + """Sanitize boot options from console and init + + Args: + boot_opts (str): boot options + + Returns: + str: sanitized boot options + """ + regex_filter = compile(REGEX_SANIT_CONSOLE) + boot_opts = regex_filter.sub('', boot_opts) + regex_filter = compile(REGEX_SANIT_INIT) + boot_opts = regex_filter.sub('', boot_opts) + + return boot_opts + + +def parse_entry(entry: tuple) -> dict: + """Parse GRUB menuentry + + Args: + entry (tuple): tuple of (version, options) + + Returns: + dict: dictionary with parsed options + """ + # save version to dict + entry_dict = {'version': entry[0]} + # detect boot mode type + if PW_RESET_OPTION in entry[1]: + entry_dict['bootmode'] = 'pw_reset' + else: + entry_dict['bootmode'] = 'normal' + # find console type and number + regex_filter = compile(REGEX_CONSOLE) + entry_dict.update(regex_filter.match(entry[1]).groupdict()) + entry_dict['boot_opts'] = sanitize_boot_opts(entry[1]) + + return entry_dict + + +def parse_menuntries(grub_path: str) -> list: + """Parse all GRUB menuentries + + Args: + grub_path (str): a path to GRUB config file + + Returns: + list: list with menu items (each item is a dict) + """ + menuentries = [] + # read configuration file + config_text = Path(grub_path).read_text() + # parse menuentries to tuples (version, options) + regex_filter = compile(REGEX_MENUENTRY, MULTILINE) + filter_results = regex_filter.findall(config_text) + # parse each entry + for entry in filter_results: + menuentries.append(parse_entry(entry)) + + return menuentries + + +if __name__ == '__main__': + # Skip everything if update is not required + if not cfg_check_update(): + exit(0) + + # find root directory of persistent storage + root_dir = disk.find_persistence() + + # read current GRUB config + grub_cfg_main = f'{root_dir}/{image.GRUB_DIR_MAIN}/grub.cfg' + vars = grub.vars_read(grub_cfg_main) + modules = grub.modules_read(grub_cfg_main) + vyos_menuentries = parse_menuntries(grub_cfg_main) + vyos_versions = find_versions(vyos_menuentries) + unparsed_items = filter_unparsed(grub_cfg_main) + + # find default values + default_entry = vyos_menuentries[int(vars['default'])] + default_settings = { + 'default': grub.gen_version_uuid(default_entry['version']), + 'bootmode': default_entry['bootmode'], + 'console_type': default_entry['console_type'], + 'console_num': default_entry['console_num'] + } + vars.update(default_settings) + + # print(f'vars: {vars}') + # print(f'modules: {modules}') + # print(f'vyos_menuentries: {vyos_menuentries}') + # print(f'unparsed_items: {unparsed_items}') + + # create new files + grub_cfg_vars = f'{root_dir}/{image.CFG_VYOS_VARS}' + grub_cfg_modules = f'{root_dir}/{grub.CFG_VYOS_MODULES}' + grub_cfg_platform = f'{root_dir}/{grub.CFG_VYOS_PLATFORM}' + grub_cfg_menu = f'{root_dir}/{grub.CFG_VYOS_MENU}' + grub_cfg_options = f'{root_dir}/{grub.CFG_VYOS_OPTIONS}' + + render(grub_cfg_main, grub.TMPL_GRUB_MAIN, {}) + Path(image.GRUB_DIR_VYOS).mkdir(exist_ok=True) + grub.vars_write(grub_cfg_vars, vars) + grub.modules_write(grub_cfg_modules, modules) + # Path(grub_cfg_platform).write_text(unparsed_items) + grub.common_write() + render(grub_cfg_menu, grub.TMPL_GRUB_MENU, {}) + render(grub_cfg_options, grub.TMPL_GRUB_OPTS, {}) + + # create menu entries + for vyos_ver in vyos_versions: + boot_opts = None + for entry in vyos_menuentries: + if entry.get('version') == vyos_ver and entry.get( + 'bootmode') == 'normal': + boot_opts = entry.get('boot_opts') + grub.version_add(vyos_ver, root_dir, boot_opts) + + # update structure version + grub.write_cfg_ver(CFG_VER, root_dir) + exit(0) |