xref: /openbmc/openbmc/poky/scripts/lib/wic/ksparser.py (revision 5082cc7f)
1#!/usr/bin/env python3
2#
3# Copyright (c) 2016 Intel, Inc.
4#
5# SPDX-License-Identifier: GPL-2.0-only
6#
7# DESCRIPTION
8# This module provides parser for kickstart format
9#
10# AUTHORS
11# Ed Bartosh <ed.bartosh> (at] linux.intel.com>
12
13"""Kickstart parser module."""
14
15import os
16import shlex
17import logging
18import re
19
20from argparse import ArgumentParser, ArgumentError, ArgumentTypeError
21
22from wic.engine import find_canned
23from wic.partition import Partition
24from wic.misc import get_bitbake_var
25
26logger = logging.getLogger('wic')
27
28__expand_var_regexp__ = re.compile(r"\${[^{}@\n\t :]+}")
29
30def expand_line(line):
31    while True:
32        m = __expand_var_regexp__.search(line)
33        if not m:
34            return line
35        key = m.group()[2:-1]
36        val = get_bitbake_var(key)
37        if val is None:
38            logger.warning("cannot expand variable %s" % key)
39            return line
40        line = line[:m.start()] + val + line[m.end():]
41
42class KickStartError(Exception):
43    """Custom exception."""
44    pass
45
46class KickStartParser(ArgumentParser):
47    """
48    This class overwrites error method to throw exception
49    instead of producing usage message(default argparse behavior).
50    """
51    def error(self, message):
52        raise ArgumentError(None, message)
53
54def sizetype(default, size_in_bytes=False):
55    def f(arg):
56        """
57        Custom type for ArgumentParser
58        Converts size string in <num>[S|s|K|k|M|G] format into the integer value
59        """
60        try:
61            suffix = default
62            size = int(arg)
63        except ValueError:
64            try:
65                suffix = arg[-1:]
66                size = int(arg[:-1])
67            except ValueError:
68                raise ArgumentTypeError("Invalid size: %r" % arg)
69
70
71        if size_in_bytes:
72            if suffix == 's' or suffix == 'S':
73                return size * 512
74            mult = 1024
75        else:
76            mult = 1
77
78        if suffix == "k" or suffix == "K":
79            return size * mult
80        if suffix == "M":
81            return size * mult * 1024
82        if suffix == "G":
83            return size * mult * 1024 * 1024
84
85        raise ArgumentTypeError("Invalid size: %r" % arg)
86    return f
87
88def overheadtype(arg):
89    """
90    Custom type for ArgumentParser
91    Converts overhead string to float and checks if it's bigger than 1.0
92    """
93    try:
94        result = float(arg)
95    except ValueError:
96        raise ArgumentTypeError("Invalid value: %r" % arg)
97
98    if result < 1.0:
99        raise ArgumentTypeError("Overhead factor should be > 1.0" % arg)
100
101    return result
102
103def cannedpathtype(arg):
104    """
105    Custom type for ArgumentParser
106    Tries to find file in the list of canned wks paths
107    """
108    scripts_path = os.path.abspath(os.path.dirname(__file__) + '../../..')
109    result = find_canned(scripts_path, arg)
110    if not result:
111        raise ArgumentTypeError("file not found: %s" % arg)
112    return result
113
114def systemidtype(arg):
115    """
116    Custom type for ArgumentParser
117    Checks if the argument sutisfies system id requirements,
118    i.e. if it's one byte long integer > 0
119    """
120    error = "Invalid system type: %s. must be hex "\
121            "between 0x1 and 0xFF" % arg
122    try:
123        result = int(arg, 16)
124    except ValueError:
125        raise ArgumentTypeError(error)
126
127    if result <= 0 or result > 0xff:
128        raise ArgumentTypeError(error)
129
130    return arg
131
132class KickStart():
133    """Kickstart parser implementation."""
134
135    DEFAULT_EXTRA_SPACE = 10*1024
136    DEFAULT_OVERHEAD_FACTOR = 1.3
137
138    def __init__(self, confpath):
139
140        self.partitions = []
141        self.bootloader = None
142        self.lineno = 0
143        self.partnum = 0
144
145        parser = KickStartParser()
146        subparsers = parser.add_subparsers()
147
148        part = subparsers.add_parser('part')
149        part.add_argument('mountpoint', nargs='?')
150        part.add_argument('--active', action='store_true')
151        part.add_argument('--align', type=int)
152        part.add_argument('--offset', type=sizetype("K", True))
153        part.add_argument('--exclude-path', nargs='+')
154        part.add_argument('--include-path', nargs='+', action='append')
155        part.add_argument('--change-directory')
156        part.add_argument("--extra-space", type=sizetype("M"))
157        part.add_argument('--fsoptions', dest='fsopts')
158        part.add_argument('--fspassno', dest='fspassno')
159        part.add_argument('--fstype', default='vfat',
160                          choices=('ext2', 'ext3', 'ext4', 'btrfs',
161                                   'squashfs', 'vfat', 'msdos', 'erofs',
162                                   'swap', 'none'))
163        part.add_argument('--mkfs-extraopts', default='')
164        part.add_argument('--label')
165        part.add_argument('--use-label', action='store_true')
166        part.add_argument('--no-table', action='store_true')
167        part.add_argument('--ondisk', '--ondrive', dest='disk', default='sda')
168        part.add_argument("--overhead-factor", type=overheadtype)
169        part.add_argument('--part-name')
170        part.add_argument('--part-type')
171        part.add_argument('--rootfs-dir')
172        part.add_argument('--type', default='primary',
173                choices = ('primary', 'logical'))
174        part.add_argument('--hidden', action='store_true')
175
176        # --size and --fixed-size cannot be specified together; options
177        # ----extra-space and --overhead-factor should also raise a parser
178        # --error, but since nesting mutually exclusive groups does not work,
179        # ----extra-space/--overhead-factor are handled later
180        sizeexcl = part.add_mutually_exclusive_group()
181        sizeexcl.add_argument('--size', type=sizetype("M"), default=0)
182        sizeexcl.add_argument('--fixed-size', type=sizetype("M"), default=0)
183
184        part.add_argument('--source')
185        part.add_argument('--sourceparams')
186        part.add_argument('--system-id', type=systemidtype)
187        part.add_argument('--use-uuid', action='store_true')
188        part.add_argument('--uuid')
189        part.add_argument('--fsuuid')
190        part.add_argument('--no-fstab-update', action='store_true')
191        part.add_argument('--mbr', action='store_true')
192
193        bootloader = subparsers.add_parser('bootloader')
194        bootloader.add_argument('--append')
195        bootloader.add_argument('--configfile')
196        bootloader.add_argument('--ptable', choices=('msdos', 'gpt', 'gpt-hybrid'),
197                                default='msdos')
198        bootloader.add_argument('--timeout', type=int)
199        bootloader.add_argument('--source')
200
201        include = subparsers.add_parser('include')
202        include.add_argument('path', type=cannedpathtype)
203
204        self._parse(parser, confpath)
205        if not self.bootloader:
206            logger.warning('bootloader config not specified, using defaults\n')
207            self.bootloader = bootloader.parse_args([])
208
209    def _parse(self, parser, confpath):
210        """
211        Parse file in .wks format using provided parser.
212        """
213        with open(confpath) as conf:
214            lineno = 0
215            for line in conf:
216                line = line.strip()
217                lineno += 1
218                if line and line[0] != '#':
219                    line = expand_line(line)
220                    try:
221                        line_args = shlex.split(line)
222                        parsed = parser.parse_args(line_args)
223                    except ArgumentError as err:
224                        raise KickStartError('%s:%d: %s' % \
225                                             (confpath, lineno, err))
226                    if line.startswith('part'):
227                        # SquashFS does not support filesystem UUID
228                        if parsed.fstype == 'squashfs':
229                            if parsed.fsuuid:
230                                err = "%s:%d: SquashFS does not support UUID" \
231                                       % (confpath, lineno)
232                                raise KickStartError(err)
233                            if parsed.label:
234                                err = "%s:%d: SquashFS does not support LABEL" \
235                                       % (confpath, lineno)
236                                raise KickStartError(err)
237                        # erofs does not support filesystem labels
238                        if parsed.fstype == 'erofs' and parsed.label:
239                            err = "%s:%d: erofs does not support LABEL" % (confpath, lineno)
240                            raise KickStartError(err)
241                        if parsed.fstype == 'msdos' or parsed.fstype == 'vfat':
242                            if parsed.fsuuid:
243                                if parsed.fsuuid.upper().startswith('0X'):
244                                    if len(parsed.fsuuid) > 10:
245                                        err = "%s:%d: fsuuid %s given in wks kickstart file " \
246                                              "exceeds the length limit for %s filesystem. " \
247                                              "It should be in the form of a 32 bit hexadecimal" \
248                                              "number (for example, 0xABCD1234)." \
249                                              % (confpath, lineno, parsed.fsuuid, parsed.fstype)
250                                        raise KickStartError(err)
251                                elif len(parsed.fsuuid) > 8:
252                                    err = "%s:%d: fsuuid %s given in wks kickstart file " \
253                                          "exceeds the length limit for %s filesystem. " \
254                                          "It should be in the form of a 32 bit hexadecimal" \
255                                          "number (for example, 0xABCD1234)." \
256                                          % (confpath, lineno, parsed.fsuuid, parsed.fstype)
257                                    raise KickStartError(err)
258                        if parsed.use_label and not parsed.label:
259                            err = "%s:%d: Must set the label with --label" \
260                                  % (confpath, lineno)
261                            raise KickStartError(err)
262                        # using ArgumentParser one cannot easily tell if option
263                        # was passed as argument, if said option has a default
264                        # value; --overhead-factor/--extra-space cannot be used
265                        # with --fixed-size, so at least detect when these were
266                        # passed with non-0 values ...
267                        if parsed.fixed_size:
268                            if parsed.overhead_factor or parsed.extra_space:
269                                err = "%s:%d: arguments --overhead-factor and --extra-space not "\
270                                      "allowed with argument --fixed-size" \
271                                      % (confpath, lineno)
272                                raise KickStartError(err)
273                        else:
274                            # ... and provide defaults if not using
275                            # --fixed-size iff given option was not used
276                            # (again, one cannot tell if option was passed but
277                            # with value equal to 0)
278                            if '--overhead-factor' not in line_args:
279                                parsed.overhead_factor = self.DEFAULT_OVERHEAD_FACTOR
280                            if '--extra-space' not in line_args:
281                                parsed.extra_space = self.DEFAULT_EXTRA_SPACE
282
283                        self.partnum += 1
284                        self.partitions.append(Partition(parsed, self.partnum))
285                    elif line.startswith('include'):
286                        self._parse(parser, parsed.path)
287                    elif line.startswith('bootloader'):
288                        if not self.bootloader:
289                            self.bootloader = parsed
290                            # Concatenate the strings set in APPEND
291                            append_var = get_bitbake_var("APPEND")
292                            if append_var:
293                                self.bootloader.append = ' '.join(filter(None, \
294                                                         (self.bootloader.append, append_var)))
295                        else:
296                            err = "%s:%d: more than one bootloader specified" \
297                                      % (confpath, lineno)
298                            raise KickStartError(err)
299