1 # SPDX-License-Identifier: GPL-2.0+
2 # Copyright (c) 2018 Google, Inc
3 # Written by Simon Glass <sjg@chromium.org>
6 # Support for a Chromium OS verified boot block, used to sign a read-write
7 # section of the image.
9 from collections import OrderedDict
12 from entry import Entry, EntryArg
17 class Entry_vblock(Entry):
18 """An entry which contains a Chromium OS verified boot block
20 Properties / Entry arguments:
21 - content: List of phandles to entries to sign
22 - keydir: Directory containing the public keys to use
23 - keyblock: Name of the key file to use (inside keydir)
24 - signprivate: Name of provide key file to use (inside keydir)
25 - version: Version number of the vblock (typically 1)
26 - kernelkey: Name of the kernel key to use (inside keydir)
27 - preamble-flags: Value of the vboot preamble flags (typically 0)
30 - input.<unique_name> - input file passed to futility
31 - vblock.<unique_name> - output file generated by futility (which is
32 used as the entry contents)
34 Chromium OS signs the read-write firmware and kernel, writing the signature
35 in this block. This allows U-Boot to verify that the next firmware stage
36 and kernel are genuine.
38 def __init__(self, section, etype, node):
39 Entry.__init__(self, section, etype, node)
40 self.content = fdt_util.GetPhandleList(self._node, 'content')
42 self.Raise("Vblock must have a 'content' property")
43 (self.keydir, self.keyblock, self.signprivate, self.version,
44 self.kernelkey, self.preamble_flags) = self.GetEntryArgsOrProps([
45 EntryArg('keydir', str),
46 EntryArg('keyblock', str),
47 EntryArg('signprivate', str),
48 EntryArg('version', int),
49 EntryArg('kernelkey', str),
50 EntryArg('preamble-flags', int)])
52 def ObtainContents(self):
53 # Join up the data files to be signed
55 for entry_phandle in self.content:
56 data = self.section.GetContentsByPhandle(entry_phandle, self)
58 # Data not available yet
62 uniq = self.GetUniqueName()
63 output_fname = tools.GetOutputFilename('vblock.%s' % uniq)
64 input_fname = tools.GetOutputFilename('input.%s' % uniq)
65 tools.WriteFile(input_fname, input_data)
66 prefix = self.keydir + '/'
69 '--vblock', output_fname,
70 '--keyblock', prefix + self.keyblock,
71 '--signprivate', prefix + self.signprivate,
72 '--version', '%d' % self.version,
74 '--kernelkey', prefix + self.kernelkey,
75 '--flags', '%d' % self.preamble_flags,
77 #out.Notice("Sign '%s' into %s" % (', '.join(self.value), self.label))
78 stdout = tools.Run('futility', *args)
79 self.SetContents(tools.ReadFile(output_fname))