+# SPDX-License-Identifier: GPL-2.0+
# Copyright (c) 2016 Google, Inc
# Written by Simon Glass <sjg@chromium.org>
#
-# SPDX-License-Identifier: GPL-2.0+
-#
# Handle various things related to ELF images
#
from collections import namedtuple, OrderedDict
-import command
+import io
import os
import re
+import shutil
import struct
+import tempfile
-import tools
+from patman import command
+from patman import tools
+from patman import tout
-# This is enabled from control.py
-debug = False
+ELF_TOOLS = True
+try:
+ from elftools.elf.elffile import ELFFile
+ from elftools.elf.sections import SymbolTableSection
+except: # pragma: no cover
+ ELF_TOOLS = False
Symbol = namedtuple('Symbol', ['section', 'address', 'size', 'weak'])
+# Information about an ELF file:
+# data: Extracted program contents of ELF file (this would be loaded by an
+# ELF loader when reading this file
+# load: Load address of code
+# entry: Entry address of code
+# memsize: Number of bytes in memory occupied by loading this ELF file
+ElfInfo = namedtuple('ElfInfo', ['data', 'load', 'entry', 'memsize'])
+
def GetSymbols(fname, patterns):
"""Get the symbols from an ELF file
key: Name of symbol
value: Hex value of symbol
"""
- stdout = command.Output('objdump', '-t', fname, raise_on_error=False)
+ stdout = tools.Run('objdump', '-t', fname)
lines = stdout.splitlines()
if patterns:
re_syms = re.compile('|'.join(patterns))
parts = rest[7:].split()
section, size = parts[:2]
if len(parts) > 2:
- name = parts[2]
+ name = parts[2] if parts[2] != '.hidden' else parts[3]
syms[name] = Symbol(section, int(value, 16), int(size,16),
flags[1] == 'w')
- return syms
+
+ # Sort dict by address
+ return OrderedDict(sorted(syms.items(), key=lambda x: x[1].address))
def GetSymbolAddress(fname, sym_name):
"""Get a value of a symbol from an ELF file
return None
return sym.address
-def LookupAndWriteSymbols(elf_fname, entry, image):
+def LookupAndWriteSymbols(elf_fname, entry, section):
"""Replace all symbols in an entry with their correct values
The entry contents is updated so that values for referenced symbols will be
- visible at run time. This is done by finding out the symbols positions in
- the entry (using the ELF file) and replacing them with values from binman's
- data structures.
+ visible at run time. This is done by finding out the symbols offsets in the
+ entry (using the ELF file) and replacing them with values from binman's data
+ structures.
Args:
elf_fname: Filename of ELF image containing the symbol information for
entry
entry: Entry to process
- image: Image which can be used to lookup symbol values
+ section: Section which can be used to lookup symbol values
"""
fname = tools.GetInputFilename(elf_fname)
syms = GetSymbols(fname, ['image', 'binman'])
base = syms.get('__image_copy_start')
if not base:
return
- for name, sym in syms.iteritems():
+ for name, sym in syms.items():
if name.startswith('_binman'):
- msg = ("Image '%s': Symbol '%s'\n in entry '%s'" %
- (image.GetPath(), name, entry.GetPath()))
+ msg = ("Section '%s': Symbol '%s'\n in entry '%s'" %
+ (section.GetPath(), name, entry.GetPath()))
offset = sym.address - base.address
if offset < 0 or offset + sym.size > entry.contents_size:
raise ValueError('%s has offset %x (size %x) but the contents '
(msg, sym.size))
# Look up the symbol in our entry tables.
- value = image.LookupSymbol(name, sym.weak, msg)
- if value is not None:
- value += base.address
- else:
+ value = section.LookupSymbol(name, sym.weak, msg, base.address)
+ if value is None:
value = -1
pack_string = pack_string.lower()
value_bytes = struct.pack(pack_string, value)
- if debug:
- print('%s:\n insert %s, offset %x, value %x, length %d' %
- (msg, name, offset, value, len(value_bytes)))
+ tout.Debug('%s:\n insert %s, offset %x, value %x, length %d' %
+ (msg, name, offset, value, len(value_bytes)))
entry.data = (entry.data[:offset] + value_bytes +
entry.data[offset + sym.size:])
+
+def MakeElf(elf_fname, text, data):
+ """Make an elf file with the given data in a single section
+
+ The output file has a several section including '.text' and '.data',
+ containing the info provided in arguments.
+
+ Args:
+ elf_fname: Output filename
+ text: Text (code) to put in the file's .text section
+ data: Data to put in the file's .data section
+ """
+ outdir = tempfile.mkdtemp(prefix='binman.elf.')
+ s_file = os.path.join(outdir, 'elf.S')
+
+ # Spilt the text into two parts so that we can make the entry point two
+ # bytes after the start of the text section
+ text_bytes1 = ['\t.byte\t%#x' % tools.ToByte(byte) for byte in text[:2]]
+ text_bytes2 = ['\t.byte\t%#x' % tools.ToByte(byte) for byte in text[2:]]
+ data_bytes = ['\t.byte\t%#x' % tools.ToByte(byte) for byte in data]
+ with open(s_file, 'w') as fd:
+ print('''/* Auto-generated C program to produce an ELF file for testing */
+
+.section .text
+.code32
+.globl _start
+.type _start, @function
+%s
+_start:
+%s
+.ident "comment"
+
+.comm fred,8,4
+
+.section .empty
+.globl _empty
+_empty:
+.byte 1
+
+.globl ernie
+.data
+.type ernie, @object
+.size ernie, 4
+ernie:
+%s
+''' % ('\n'.join(text_bytes1), '\n'.join(text_bytes2), '\n'.join(data_bytes)),
+ file=fd)
+ lds_file = os.path.join(outdir, 'elf.lds')
+
+ # Use a linker script to set the alignment and text address.
+ with open(lds_file, 'w') as fd:
+ print('''/* Auto-generated linker script to produce an ELF file for testing */
+
+PHDRS
+{
+ text PT_LOAD ;
+ data PT_LOAD ;
+ empty PT_LOAD FLAGS ( 6 ) ;
+ note PT_NOTE ;
+}
+
+SECTIONS
+{
+ . = 0xfef20000;
+ ENTRY(_start)
+ .text . : SUBALIGN(0)
+ {
+ *(.text)
+ } :text
+ .data : {
+ *(.data)
+ } :data
+ _bss_start = .;
+ .empty : {
+ *(.empty)
+ } :empty
+ /DISCARD/ : {
+ *(.note.gnu.property)
+ }
+ .note : {
+ *(.comment)
+ } :note
+ .bss _bss_start (OVERLAY) : {
+ *(.bss)
+ }
+}
+''', file=fd)
+ # -static: Avoid requiring any shared libraries
+ # -nostdlib: Don't link with C library
+ # -Wl,--build-id=none: Don't generate a build ID, so that we just get the
+ # text section at the start
+ # -m32: Build for 32-bit x86
+ # -T...: Specifies the link script, which sets the start address
+ stdout = command.Output('cc', '-static', '-nostdlib', '-Wl,--build-id=none',
+ '-m32','-T', lds_file, '-o', elf_fname, s_file)
+ shutil.rmtree(outdir)
+
+def DecodeElf(data, location):
+ """Decode an ELF file and return information about it
+
+ Args:
+ data: Data from ELF file
+ location: Start address of data to return
+
+ Returns:
+ ElfInfo object containing information about the decoded ELF file
+ """
+ file_size = len(data)
+ with io.BytesIO(data) as fd:
+ elf = ELFFile(fd)
+ data_start = 0xffffffff;
+ data_end = 0;
+ mem_end = 0;
+ virt_to_phys = 0;
+
+ for i in range(elf.num_segments()):
+ segment = elf.get_segment(i)
+ if segment['p_type'] != 'PT_LOAD' or not segment['p_memsz']:
+ skipped = 1 # To make code-coverage see this line
+ continue
+ start = segment['p_paddr']
+ mend = start + segment['p_memsz']
+ rend = start + segment['p_filesz']
+ data_start = min(data_start, start)
+ data_end = max(data_end, rend)
+ mem_end = max(mem_end, mend)
+ if not virt_to_phys:
+ virt_to_phys = segment['p_paddr'] - segment['p_vaddr']
+
+ output = bytearray(data_end - data_start)
+ for i in range(elf.num_segments()):
+ segment = elf.get_segment(i)
+ if segment['p_type'] != 'PT_LOAD' or not segment['p_memsz']:
+ skipped = 1 # To make code-coverage see this line
+ continue
+ start = segment['p_paddr']
+ offset = 0
+ if start < location:
+ offset = location - start
+ start = location
+ # A legal ELF file can have a program header with non-zero length
+ # but zero-length file size and a non-zero offset which, added
+ # together, are greater than input->size (i.e. the total file size).
+ # So we need to not even test in the case that p_filesz is zero.
+ # Note: All of this code is commented out since we don't have a test
+ # case for it.
+ size = segment['p_filesz']
+ #if not size:
+ #continue
+ #end = segment['p_offset'] + segment['p_filesz']
+ #if end > file_size:
+ #raise ValueError('Underflow copying out the segment. File has %#x bytes left, segment end is %#x\n',
+ #file_size, end)
+ output[start - data_start:start - data_start + size] = (
+ segment.data()[offset:])
+ return ElfInfo(output, data_start, elf.header['e_entry'] + virt_to_phys,
+ mem_end - data_start)
projects / oweals / u-boot.git / blobdiff