u-boot/tools/binman/entry.py
Simon Glass e0e5df9310 binman: Support hashing entries
Sometimesi it us useful to be able to verify the content of entries with
a hash. Add an easy way to do this in binman. The hash information can be
retrieved from the device tree at run time.

Signed-off-by: Simon Glass <sjg@chromium.org>
2018-09-29 11:49:35 -06:00

525 lines
18 KiB
Python

# SPDX-License-Identifier: GPL-2.0+
# Copyright (c) 2016 Google, Inc
#
# Base class for all entries
#
from __future__ import print_function
from collections import namedtuple
# importlib was introduced in Python 2.7 but there was a report of it not
# working in 2.7.12, so we work around this:
# http://lists.denx.de/pipermail/u-boot/2016-October/269729.html
try:
import importlib
have_importlib = True
except:
have_importlib = False
import os
from sets import Set
import sys
import fdt_util
import state
import tools
modules = {}
our_path = os.path.dirname(os.path.realpath(__file__))
# An argument which can be passed to entries on the command line, in lieu of
# device-tree properties.
EntryArg = namedtuple('EntryArg', ['name', 'datatype'])
class Entry(object):
"""An Entry in the section
An entry corresponds to a single node in the device-tree description
of the section. Each entry ends up being a part of the final section.
Entries can be placed either right next to each other, or with padding
between them. The type of the entry determines the data that is in it.
This class is not used by itself. All entry objects are subclasses of
Entry.
Attributes:
section: Section object containing this entry
node: The node that created this entry
offset: Offset of entry within the section, None if not known yet (in
which case it will be calculated by Pack())
size: Entry size in bytes, None if not known
contents_size: Size of contents in bytes, 0 by default
align: Entry start offset alignment, or None
align_size: Entry size alignment, or None
align_end: Entry end offset alignment, or None
pad_before: Number of pad bytes before the contents, 0 if none
pad_after: Number of pad bytes after the contents, 0 if none
data: Contents of entry (string of bytes)
"""
def __init__(self, section, etype, node, read_node=True, name_prefix=''):
self.section = section
self.etype = etype
self._node = node
self.name = node and (name_prefix + node.name) or 'none'
self.offset = None
self.size = None
self.data = None
self.contents_size = 0
self.align = None
self.align_size = None
self.align_end = None
self.pad_before = 0
self.pad_after = 0
self.offset_unset = False
self.image_pos = None
self._expand_size = False
if read_node:
self.ReadNode()
@staticmethod
def Lookup(section, node_path, etype):
"""Look up the entry class for a node.
Args:
section: Section object containing this node
node_node: Path name of Node object containing information about
the entry to create (used for errors)
etype: Entry type to use
Returns:
The entry class object if found, else None
"""
# Convert something like 'u-boot@0' to 'u_boot' since we are only
# interested in the type.
module_name = etype.replace('-', '_')
if '@' in module_name:
module_name = module_name.split('@')[0]
module = modules.get(module_name)
# Also allow entry-type modules to be brought in from the etype directory.
# Import the module if we have not already done so.
if not module:
old_path = sys.path
sys.path.insert(0, os.path.join(our_path, 'etype'))
try:
if have_importlib:
module = importlib.import_module(module_name)
else:
module = __import__(module_name)
except ImportError as e:
raise ValueError("Unknown entry type '%s' in node '%s' (expected etype/%s.py, error '%s'" %
(etype, node_path, module_name, e))
finally:
sys.path = old_path
modules[module_name] = module
# Look up the expected class name
return getattr(module, 'Entry_%s' % module_name)
@staticmethod
def Create(section, node, etype=None):
"""Create a new entry for a node.
Args:
section: Section object containing this node
node: Node object containing information about the entry to
create
etype: Entry type to use, or None to work it out (used for tests)
Returns:
A new Entry object of the correct type (a subclass of Entry)
"""
if not etype:
etype = fdt_util.GetString(node, 'type', node.name)
obj = Entry.Lookup(section, node.path, etype)
# Call its constructor to get the object we want.
return obj(section, etype, node)
def ReadNode(self):
"""Read entry information from the node
This reads all the fields we recognise from the node, ready for use.
"""
if 'pos' in self._node.props:
self.Raise("Please use 'offset' instead of 'pos'")
self.offset = fdt_util.GetInt(self._node, 'offset')
self.size = fdt_util.GetInt(self._node, 'size')
self.align = fdt_util.GetInt(self._node, 'align')
if tools.NotPowerOfTwo(self.align):
raise ValueError("Node '%s': Alignment %s must be a power of two" %
(self._node.path, self.align))
self.pad_before = fdt_util.GetInt(self._node, 'pad-before', 0)
self.pad_after = fdt_util.GetInt(self._node, 'pad-after', 0)
self.align_size = fdt_util.GetInt(self._node, 'align-size')
if tools.NotPowerOfTwo(self.align_size):
raise ValueError("Node '%s': Alignment size %s must be a power "
"of two" % (self._node.path, self.align_size))
self.align_end = fdt_util.GetInt(self._node, 'align-end')
self.offset_unset = fdt_util.GetBool(self._node, 'offset-unset')
self.expand_size = fdt_util.GetBool(self._node, 'expand-size')
def GetDefaultFilename(self):
return None
def GetFdtSet(self):
"""Get the set of device trees used by this entry
Returns:
Set containing the filename from this entry, if it is a .dtb, else
an empty set
"""
fname = self.GetDefaultFilename()
# It would be better to use isinstance(self, Entry_blob_dtb) here but
# we cannot access Entry_blob_dtb
if fname and fname.endswith('.dtb'):
return Set([fname])
return Set()
def ExpandEntries(self):
pass
def AddMissingProperties(self):
"""Add new properties to the device tree as needed for this entry"""
for prop in ['offset', 'size', 'image-pos']:
if not prop in self._node.props:
state.AddZeroProp(self._node, prop)
err = state.CheckAddHashProp(self._node)
if err:
self.Raise(err)
def SetCalculatedProperties(self):
"""Set the value of device-tree properties calculated by binman"""
state.SetInt(self._node, 'offset', self.offset)
state.SetInt(self._node, 'size', self.size)
state.SetInt(self._node, 'image-pos', self.image_pos)
state.CheckSetHashValue(self._node, self.GetData)
def ProcessFdt(self, fdt):
"""Allow entries to adjust the device tree
Some entries need to adjust the device tree for their purposes. This
may involve adding or deleting properties.
Returns:
True if processing is complete
False if processing could not be completed due to a dependency.
This will cause the entry to be retried after others have been
called
"""
return True
def SetPrefix(self, prefix):
"""Set the name prefix for a node
Args:
prefix: Prefix to set, or '' to not use a prefix
"""
if prefix:
self.name = prefix + self.name
def SetContents(self, data):
"""Set the contents of an entry
This sets both the data and content_size properties
Args:
data: Data to set to the contents (string)
"""
self.data = data
self.contents_size = len(self.data)
def ProcessContentsUpdate(self, data):
"""Update the contens of an entry, after the size is fixed
This checks that the new data is the same size as the old.
Args:
data: Data to set to the contents (string)
Raises:
ValueError if the new data size is not the same as the old
"""
if len(data) != self.contents_size:
self.Raise('Cannot update entry size from %d to %d' %
(len(data), self.contents_size))
self.SetContents(data)
def ObtainContents(self):
"""Figure out the contents of an entry.
Returns:
True if the contents were found, False if another call is needed
after the other entries are processed.
"""
# No contents by default: subclasses can implement this
return True
def Pack(self, offset):
"""Figure out how to pack the entry into the section
Most of the time the entries are not fully specified. There may be
an alignment but no size. In that case we take the size from the
contents of the entry.
If an entry has no hard-coded offset, it will be placed at @offset.
Once this function is complete, both the offset and size of the
entry will be know.
Args:
Current section offset pointer
Returns:
New section offset pointer (after this entry)
"""
if self.offset is None:
if self.offset_unset:
self.Raise('No offset set with offset-unset: should another '
'entry provide this correct offset?')
self.offset = tools.Align(offset, self.align)
needed = self.pad_before + self.contents_size + self.pad_after
needed = tools.Align(needed, self.align_size)
size = self.size
if not size:
size = needed
new_offset = self.offset + size
aligned_offset = tools.Align(new_offset, self.align_end)
if aligned_offset != new_offset:
size = aligned_offset - self.offset
new_offset = aligned_offset
if not self.size:
self.size = size
if self.size < needed:
self.Raise("Entry contents size is %#x (%d) but entry size is "
"%#x (%d)" % (needed, needed, self.size, self.size))
# Check that the alignment is correct. It could be wrong if the
# and offset or size values were provided (i.e. not calculated), but
# conflict with the provided alignment values
if self.size != tools.Align(self.size, self.align_size):
self.Raise("Size %#x (%d) does not match align-size %#x (%d)" %
(self.size, self.size, self.align_size, self.align_size))
if self.offset != tools.Align(self.offset, self.align):
self.Raise("Offset %#x (%d) does not match align %#x (%d)" %
(self.offset, self.offset, self.align, self.align))
return new_offset
def Raise(self, msg):
"""Convenience function to raise an error referencing a node"""
raise ValueError("Node '%s': %s" % (self._node.path, msg))
def GetEntryArgsOrProps(self, props, required=False):
"""Return the values of a set of properties
Args:
props: List of EntryArg objects
Raises:
ValueError if a property is not found
"""
values = []
missing = []
for prop in props:
python_prop = prop.name.replace('-', '_')
if hasattr(self, python_prop):
value = getattr(self, python_prop)
else:
value = None
if value is None:
value = self.GetArg(prop.name, prop.datatype)
if value is None and required:
missing.append(prop.name)
values.append(value)
if missing:
self.Raise('Missing required properties/entry args: %s' %
(', '.join(missing)))
return values
def GetPath(self):
"""Get the path of a node
Returns:
Full path of the node for this entry
"""
return self._node.path
def GetData(self):
return self.data
def GetOffsets(self):
return {}
def SetOffsetSize(self, pos, size):
self.offset = pos
self.size = size
def SetImagePos(self, image_pos):
"""Set the position in the image
Args:
image_pos: Position of this entry in the image
"""
self.image_pos = image_pos + self.offset
def ProcessContents(self):
pass
def WriteSymbols(self, section):
"""Write symbol values into binary files for access at run time
Args:
section: Section containing the entry
"""
pass
def CheckOffset(self):
"""Check that the entry offsets are correct
This is used for entries which have extra offset requirements (other
than having to be fully inside their section). Sub-classes can implement
this function and raise if there is a problem.
"""
pass
@staticmethod
def WriteMapLine(fd, indent, name, offset, size, image_pos):
print('%08x %s%08x %08x %s' % (image_pos, ' ' * indent, offset,
size, name), file=fd)
def WriteMap(self, fd, indent):
"""Write a map of the entry to a .map file
Args:
fd: File to write the map to
indent: Curent indent level of map (0=none, 1=one level, etc.)
"""
self.WriteMapLine(fd, indent, self.name, self.offset, self.size,
self.image_pos)
def GetEntries(self):
"""Return a list of entries contained by this entry
Returns:
List of entries, or None if none. A normal entry has no entries
within it so will return None
"""
return None
def GetArg(self, name, datatype=str):
"""Get the value of an entry argument or device-tree-node property
Some node properties can be provided as arguments to binman. First check
the entry arguments, and fall back to the device tree if not found
Args:
name: Argument name
datatype: Data type (str or int)
Returns:
Value of argument as a string or int, or None if no value
Raises:
ValueError if the argument cannot be converted to in
"""
value = state.GetEntryArg(name)
if value is not None:
if datatype == int:
try:
value = int(value)
except ValueError:
self.Raise("Cannot convert entry arg '%s' (value '%s') to integer" %
(name, value))
elif datatype == str:
pass
else:
raise ValueError("GetArg() internal error: Unknown data type '%s'" %
datatype)
else:
value = fdt_util.GetDatatype(self._node, name, datatype)
return value
@staticmethod
def WriteDocs(modules, test_missing=None):
"""Write out documentation about the various entry types to stdout
Args:
modules: List of modules to include
test_missing: Used for testing. This is a module to report
as missing
"""
print('''Binman Entry Documentation
===========================
This file describes the entry types supported by binman. These entry types can
be placed in an image one by one to build up a final firmware image. It is
fairly easy to create new entry types. Just add a new file to the 'etype'
directory. You can use the existing entries as examples.
Note that some entries are subclasses of others, using and extending their
features to produce new behaviours.
''')
modules = sorted(modules)
# Don't show the test entry
if '_testing' in modules:
modules.remove('_testing')
missing = []
for name in modules:
module = Entry.Lookup(name, name, name)
docs = getattr(module, '__doc__')
if test_missing == name:
docs = None
if docs:
lines = docs.splitlines()
first_line = lines[0]
rest = [line[4:] for line in lines[1:]]
hdr = 'Entry: %s: %s' % (name.replace('_', '-'), first_line)
print(hdr)
print('-' * len(hdr))
print('\n'.join(rest))
print()
print()
else:
missing.append(name)
if missing:
raise ValueError('Documentation is missing for modules: %s' %
', '.join(missing))
def GetUniqueName(self):
"""Get a unique name for a node
Returns:
String containing a unique name for a node, consisting of the name
of all ancestors (starting from within the 'binman' node) separated
by a dot ('.'). This can be useful for generating unique filesnames
in the output directory.
"""
name = self.name
node = self._node
while node.parent:
node = node.parent
if node.name == 'binman':
break
name = '%s.%s' % (node.name, name)
return name
def ExpandToLimit(self, limit):
"""Expand an entry so that it ends at the given offset limit"""
if self.offset + self.size < limit:
self.size = limit - self.offset
# Request the contents again, since changing the size requires that
# the data grows. This should not fail, but check it to be sure.
if not self.ObtainContents():
self.Raise('Cannot obtain contents when expanding entry')