1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
|
#!/usr/bin/env python3
# SPDX-License-Identifier: LGPL-2.1-or-later
# Convert ELF static PIE to PE/EFI image.
# To do so we simply copy desired ELF sections while preserving their memory layout to ensure that
# code still runs as expected. We then translate ELF relocations to PE relocations so that the EFI
# loader/firmware can properly load the binary to any address at runtime.
#
# To make this as painless as possible we only operate on static PIEs as they should only contain
# base relocations that are easy to handle as they have a one-to-one mapping to PE relocations.
#
# EDK2 does a similar process using their GenFw tool. The main difference is that they use the
# --emit-relocs linker flag, which emits a lot of different (static) ELF relocation types that have
# to be handled differently for each architecture and is overall more work than its worth.
#
# Note that on arches where binutils has PE support (x86/x86_64 mostly, aarch64 only recently)
# objcopy can be used to convert ELF to PE. But this will still not convert ELF relocations, making
# the resulting binary useless. gnu-efi relies on this method and contains a stub that performs the
# ELF dynamic relocations at runtime.
# pylint: disable=attribute-defined-outside-init
import argparse
import hashlib
import io
import os
import pathlib
import time
import typing
from ctypes import (
c_char,
c_uint8,
c_uint16,
c_uint32,
c_uint64,
LittleEndianStructure,
sizeof,
)
from elftools.elf.constants import SH_FLAGS
from elftools.elf.elffile import ELFFile
from elftools.elf.enums import (
ENUM_DT_FLAGS_1,
ENUM_RELOC_TYPE_AARCH64,
ENUM_RELOC_TYPE_ARM,
ENUM_RELOC_TYPE_i386,
ENUM_RELOC_TYPE_x64,
)
from elftools.elf.relocation import (
Relocation as ElfRelocation,
RelocationTable as ElfRelocationTable,
)
class PeCoffHeader(LittleEndianStructure):
_fields_ = (
("Machine", c_uint16),
("NumberOfSections", c_uint16),
("TimeDateStamp", c_uint32),
("PointerToSymbolTable", c_uint32),
("NumberOfSymbols", c_uint32),
("SizeOfOptionalHeader", c_uint16),
("Characteristics", c_uint16),
)
class PeDataDirectory(LittleEndianStructure):
_fields_ = (
("VirtualAddress", c_uint32),
("Size", c_uint32),
)
class PeRelocationBlock(LittleEndianStructure):
_fields_ = (
("PageRVA", c_uint32),
("BlockSize", c_uint32),
)
def __init__(self, PageRVA: int):
super().__init__(PageRVA)
self.entries: typing.List[PeRelocationEntry] = []
class PeRelocationEntry(LittleEndianStructure):
_fields_ = (
("Offset", c_uint16, 12),
("Type", c_uint16, 4),
)
class PeOptionalHeaderStart(LittleEndianStructure):
_fields_ = (
("Magic", c_uint16),
("MajorLinkerVersion", c_uint8),
("MinorLinkerVersion", c_uint8),
("SizeOfCode", c_uint32),
("SizeOfInitializedData", c_uint32),
("SizeOfUninitializedData", c_uint32),
("AddressOfEntryPoint", c_uint32),
("BaseOfCode", c_uint32),
)
class PeOptionalHeaderMiddle(LittleEndianStructure):
_fields_ = (
("SectionAlignment", c_uint32),
("FileAlignment", c_uint32),
("MajorOperatingSystemVersion", c_uint16),
("MinorOperatingSystemVersion", c_uint16),
("MajorImageVersion", c_uint16),
("MinorImageVersion", c_uint16),
("MajorSubsystemVersion", c_uint16),
("MinorSubsystemVersion", c_uint16),
("Win32VersionValue", c_uint32),
("SizeOfImage", c_uint32),
("SizeOfHeaders", c_uint32),
("CheckSum", c_uint32),
("Subsystem", c_uint16),
("DllCharacteristics", c_uint16),
)
class PeOptionalHeaderEnd(LittleEndianStructure):
_fields_ = (
("LoaderFlags", c_uint32),
("NumberOfRvaAndSizes", c_uint32),
("ExportTable", PeDataDirectory),
("ImportTable", PeDataDirectory),
("ResourceTable", PeDataDirectory),
("ExceptionTable", PeDataDirectory),
("CertificateTable", PeDataDirectory),
("BaseRelocationTable", PeDataDirectory),
("Debug", PeDataDirectory),
("Architecture", PeDataDirectory),
("GlobalPtr", PeDataDirectory),
("TLSTable", PeDataDirectory),
("LoadConfigTable", PeDataDirectory),
("BoundImport", PeDataDirectory),
("IAT", PeDataDirectory),
("DelayImportDescriptor", PeDataDirectory),
("CLRRuntimeHeader", PeDataDirectory),
("Reserved", PeDataDirectory),
)
class PeOptionalHeader(LittleEndianStructure):
pass
class PeOptionalHeader32(PeOptionalHeader):
_anonymous_ = ("Start", "Middle", "End")
_fields_ = (
("Start", PeOptionalHeaderStart),
("BaseOfData", c_uint32),
("ImageBase", c_uint32),
("Middle", PeOptionalHeaderMiddle),
("SizeOfStackReserve", c_uint32),
("SizeOfStackCommit", c_uint32),
("SizeOfHeapReserve", c_uint32),
("SizeOfHeapCommit", c_uint32),
("End", PeOptionalHeaderEnd),
)
class PeOptionalHeader32Plus(PeOptionalHeader):
_anonymous_ = ("Start", "Middle", "End")
_fields_ = (
("Start", PeOptionalHeaderStart),
("ImageBase", c_uint64),
("Middle", PeOptionalHeaderMiddle),
("SizeOfStackReserve", c_uint64),
("SizeOfStackCommit", c_uint64),
("SizeOfHeapReserve", c_uint64),
("SizeOfHeapCommit", c_uint64),
("End", PeOptionalHeaderEnd),
)
class PeSection(LittleEndianStructure):
_fields_ = (
("Name", c_char * 8),
("VirtualSize", c_uint32),
("VirtualAddress", c_uint32),
("SizeOfRawData", c_uint32),
("PointerToRawData", c_uint32),
("PointerToRelocations", c_uint32),
("PointerToLinenumbers", c_uint32),
("NumberOfRelocations", c_uint16),
("NumberOfLinenumbers", c_uint16),
("Characteristics", c_uint32),
)
def __init__(self):
super().__init__()
self.data = bytearray()
N_DATA_DIRECTORY_ENTRIES = 16
assert sizeof(PeSection) == 40
assert sizeof(PeCoffHeader) == 20
assert sizeof(PeOptionalHeader32) == 224
assert sizeof(PeOptionalHeader32Plus) == 240
PE_CHARACTERISTICS_RX = 0x60000020 # CNT_CODE|MEM_READ|MEM_EXECUTE
PE_CHARACTERISTICS_RW = 0xC0000040 # CNT_INITIALIZED_DATA|MEM_READ|MEM_WRITE
PE_CHARACTERISTICS_R = 0x40000040 # CNT_INITIALIZED_DATA|MEM_READ
IGNORE_SECTIONS = [
".eh_frame",
".eh_frame_hdr",
".ARM.exidx",
]
IGNORE_SECTION_TYPES = [
"SHT_DYNAMIC",
"SHT_DYNSYM",
"SHT_GNU_ATTRIBUTES",
"SHT_GNU_HASH",
"SHT_HASH",
"SHT_NOTE",
"SHT_REL",
"SHT_RELA",
"SHT_RELR",
"SHT_STRTAB",
"SHT_SYMTAB",
]
# EFI mandates 4KiB memory pages.
SECTION_ALIGNMENT = 4096
FILE_ALIGNMENT = 512
# Nobody cares about DOS headers, so put the PE header right after.
PE_OFFSET = 64
PE_MAGIC = b"PE\0\0"
def align_to(x: int, align: int) -> int:
return (x + align - 1) & ~(align - 1)
def align_down(x: int, align: int) -> int:
return x & ~(align - 1)
def next_section_address(sections: typing.List[PeSection]) -> int:
return align_to(
sections[-1].VirtualAddress + sections[-1].VirtualSize, SECTION_ALIGNMENT
)
def iter_copy_sections(elf: ELFFile) -> typing.Iterator[PeSection]:
pe_s = None
# This is essentially the same as copying by ELF load segments, except that we assemble them
# manually, so that we can easily strip unwanted sections. We try to only discard things we know
# about so that there are no surprises.
relro = None
for elf_seg in elf.iter_segments():
if elf_seg["p_type"] == "PT_LOAD" and elf_seg["p_align"] != SECTION_ALIGNMENT:
raise RuntimeError("ELF segments are not properly aligned.")
elif elf_seg["p_type"] == "PT_GNU_RELRO":
relro = elf_seg
for elf_s in elf.iter_sections():
if (
elf_s["sh_flags"] & SH_FLAGS.SHF_ALLOC == 0
or elf_s["sh_type"] in IGNORE_SECTION_TYPES
or elf_s.name in IGNORE_SECTIONS
):
continue
if elf_s["sh_type"] not in ["SHT_PROGBITS", "SHT_NOBITS"]:
raise RuntimeError(f"Unknown section {elf_s.name}.")
if elf_s["sh_flags"] & SH_FLAGS.SHF_EXECINSTR:
rwx = PE_CHARACTERISTICS_RX
elif elf_s["sh_flags"] & SH_FLAGS.SHF_WRITE:
rwx = PE_CHARACTERISTICS_RW
else:
rwx = PE_CHARACTERISTICS_R
# PE images are always relro.
if relro and relro.section_in_segment(elf_s):
rwx = PE_CHARACTERISTICS_R
if pe_s and pe_s.Characteristics != rwx:
yield pe_s
pe_s = None
if pe_s:
# Insert padding to properly align the section.
pad_len = elf_s["sh_addr"] - pe_s.VirtualAddress - len(pe_s.data)
pe_s.data += bytearray(pad_len) + elf_s.data()
else:
pe_s = PeSection()
pe_s.VirtualAddress = elf_s["sh_addr"]
pe_s.Characteristics = rwx
pe_s.data = elf_s.data()
if pe_s:
yield pe_s
def convert_sections(elf: ELFFile, opt: PeOptionalHeader) -> typing.List[PeSection]:
last_vma = 0
sections = []
for pe_s in iter_copy_sections(elf):
# Truncate the VMA to the nearest page and insert appropriate padding. This should not
# cause any overlap as this is pretty much how ELF *segments* are loaded/mmapped anyways.
# The ELF sections inside should also be properly aligned as we reuse the ELF VMA layout
# for the PE image.
vma = pe_s.VirtualAddress
pe_s.VirtualAddress = align_down(vma, SECTION_ALIGNMENT)
pe_s.data = bytearray(vma - pe_s.VirtualAddress) + pe_s.data
pe_s.VirtualSize = len(pe_s.data)
pe_s.SizeOfRawData = align_to(len(pe_s.data), FILE_ALIGNMENT)
pe_s.Name = {
PE_CHARACTERISTICS_RX: b".text",
PE_CHARACTERISTICS_RW: b".data",
PE_CHARACTERISTICS_R: b".rodata",
}[pe_s.Characteristics]
# This can happen if not building with `-z separate-code`.
if pe_s.VirtualAddress < last_vma:
raise RuntimeError("Overlapping PE sections.")
last_vma = pe_s.VirtualAddress + pe_s.VirtualSize
if pe_s.Name == b".text":
opt.BaseOfCode = pe_s.VirtualAddress
opt.SizeOfCode += pe_s.VirtualSize
else:
opt.SizeOfInitializedData += pe_s.VirtualSize
if pe_s.Name == b".data" and isinstance(opt, PeOptionalHeader32):
opt.BaseOfData = pe_s.VirtualAddress
sections.append(pe_s)
return sections
def copy_sections(
elf: ELFFile,
opt: PeOptionalHeader,
input_names: str,
sections: typing.List[PeSection],
):
for name in input_names.split(","):
elf_s = elf.get_section_by_name(name)
if not elf_s:
continue
if elf_s.data_alignment > 1 and SECTION_ALIGNMENT % elf_s.data_alignment != 0:
raise RuntimeError(f"ELF section {name} is not aligned.")
if elf_s["sh_flags"] & (SH_FLAGS.SHF_EXECINSTR | SH_FLAGS.SHF_WRITE) != 0:
raise RuntimeError(f"ELF section {name} is not read-only data.")
pe_s = PeSection()
pe_s.Name = name.encode()
pe_s.data = elf_s.data()
pe_s.VirtualAddress = next_section_address(sections)
pe_s.VirtualSize = len(elf_s.data())
pe_s.SizeOfRawData = align_to(len(elf_s.data()), FILE_ALIGNMENT)
pe_s.Characteristics = PE_CHARACTERISTICS_R
opt.SizeOfInitializedData += pe_s.VirtualSize
sections.append(pe_s)
def apply_elf_relative_relocation(
reloc: ElfRelocation,
image_base: int,
sections: typing.List[PeSection],
addend_size: int,
):
# fmt: off
[target] = [
pe_s for pe_s in sections
if pe_s.VirtualAddress <= reloc["r_offset"] < pe_s.VirtualAddress + len(pe_s.data)
]
# fmt: on
addend_offset = reloc["r_offset"] - target.VirtualAddress
if reloc.is_RELA():
addend = reloc["r_addend"]
else:
addend = target.data[addend_offset : addend_offset + addend_size]
addend = int.from_bytes(addend, byteorder="little")
value = (image_base + addend).to_bytes(addend_size, byteorder="little")
target.data[addend_offset : addend_offset + addend_size] = value
def convert_elf_reloc_table(
elf: ELFFile,
elf_reloc_table: ElfRelocationTable,
elf_image_base: int,
sections: typing.List[PeSection],
pe_reloc_blocks: typing.Dict[int, PeRelocationBlock],
):
NONE_RELOC = {
"EM_386": ENUM_RELOC_TYPE_i386["R_386_NONE"],
"EM_AARCH64": ENUM_RELOC_TYPE_AARCH64["R_AARCH64_NONE"],
"EM_ARM": ENUM_RELOC_TYPE_ARM["R_ARM_NONE"],
"EM_LOONGARCH": 0,
"EM_RISCV": 0,
"EM_X86_64": ENUM_RELOC_TYPE_x64["R_X86_64_NONE"],
}[elf["e_machine"]]
RELATIVE_RELOC = {
"EM_386": ENUM_RELOC_TYPE_i386["R_386_RELATIVE"],
"EM_AARCH64": ENUM_RELOC_TYPE_AARCH64["R_AARCH64_RELATIVE"],
"EM_ARM": ENUM_RELOC_TYPE_ARM["R_ARM_RELATIVE"],
"EM_LOONGARCH": 3,
"EM_RISCV": 3,
"EM_X86_64": ENUM_RELOC_TYPE_x64["R_X86_64_RELATIVE"],
}[elf["e_machine"]]
for reloc in elf_reloc_table.iter_relocations():
if reloc["r_info_type"] == NONE_RELOC:
continue
if reloc["r_info_type"] == RELATIVE_RELOC:
apply_elf_relative_relocation(
reloc, elf_image_base, sections, elf.elfclass // 8
)
# Now that the ELF relocation has been applied, we can create a PE relocation.
block_rva = reloc["r_offset"] & ~0xFFF
if block_rva not in pe_reloc_blocks:
pe_reloc_blocks[block_rva] = PeRelocationBlock(block_rva)
entry = PeRelocationEntry()
entry.Offset = reloc["r_offset"] & 0xFFF
# REL_BASED_HIGHLOW or REL_BASED_DIR64
entry.Type = 3 if elf.elfclass == 32 else 10
pe_reloc_blocks[block_rva].entries.append(entry)
continue
raise RuntimeError(f"Unsupported relocation {reloc}")
def convert_elf_relocations(
elf: ELFFile,
opt: PeOptionalHeader,
sections: typing.List[PeSection],
minimum_sections: int,
) -> typing.Optional[PeSection]:
dynamic = elf.get_section_by_name(".dynamic")
if dynamic is None:
raise RuntimeError("ELF .dynamic section is missing.")
[flags_tag] = dynamic.iter_tags("DT_FLAGS_1")
if not flags_tag["d_val"] & ENUM_DT_FLAGS_1["DF_1_PIE"]:
raise RuntimeError("ELF file is not a PIE.")
# This checks that the ELF image base is 0.
symtab = elf.get_section_by_name(".symtab")
if symtab:
exe_start = symtab.get_symbol_by_name("__executable_start")
if exe_start and exe_start[0]["st_value"] != 0:
raise RuntimeError("Unexpected ELF image base.")
opt.SizeOfHeaders = align_to(
PE_OFFSET
+ len(PE_MAGIC)
+ sizeof(PeCoffHeader)
+ sizeof(opt)
+ sizeof(PeSection) * max(len(sections) + 1, minimum_sections),
FILE_ALIGNMENT,
)
# We use the basic VMA layout from the ELF image in the PE image. This could cause the first
# section to overlap the PE image headers during runtime at VMA 0. We can simply apply a fixed
# offset relative to the PE image base when applying/converting ELF relocations. Afterwards we
# just have to apply the offset to the PE addresses so that the PE relocations work correctly on
# the ELF portions of the image.
segment_offset = 0
if sections[0].VirtualAddress < opt.SizeOfHeaders:
segment_offset = align_to(
opt.SizeOfHeaders - sections[0].VirtualAddress, SECTION_ALIGNMENT
)
opt.AddressOfEntryPoint = elf["e_entry"] + segment_offset
opt.BaseOfCode += segment_offset
if isinstance(opt, PeOptionalHeader32):
opt.BaseOfData += segment_offset
pe_reloc_blocks: typing.Dict[int, PeRelocationBlock] = {}
for reloc_type, reloc_table in dynamic.get_relocation_tables().items():
if reloc_type not in ["REL", "RELA"]:
raise RuntimeError("Unsupported relocation type {elf_reloc_type}.")
convert_elf_reloc_table(
elf, reloc_table, opt.ImageBase + segment_offset, sections, pe_reloc_blocks
)
for pe_s in sections:
pe_s.VirtualAddress += segment_offset
if len(pe_reloc_blocks) == 0:
return None
data = bytearray()
for rva in sorted(pe_reloc_blocks):
block = pe_reloc_blocks[rva]
n_relocs = len(block.entries)
# Each block must start on a 32-bit boundary. Because each entry is 16 bits
# the len has to be even. We pad by adding a none relocation.
if n_relocs % 2 != 0:
n_relocs += 1
block.entries.append(PeRelocationEntry())
block.PageRVA += segment_offset
block.BlockSize = (
sizeof(PeRelocationBlock) + sizeof(PeRelocationEntry) * n_relocs
)
data += block
for entry in sorted(block.entries, key=lambda e: e.Offset):
data += entry
pe_reloc_s = PeSection()
pe_reloc_s.Name = b".reloc"
pe_reloc_s.data = data
pe_reloc_s.VirtualAddress = next_section_address(sections)
pe_reloc_s.VirtualSize = len(data)
pe_reloc_s.SizeOfRawData = align_to(len(data), FILE_ALIGNMENT)
# CNT_INITIALIZED_DATA|MEM_READ|MEM_DISCARDABLE
pe_reloc_s.Characteristics = 0x42000040
sections.append(pe_reloc_s)
opt.SizeOfInitializedData += pe_reloc_s.VirtualSize
return pe_reloc_s
def write_pe(
file, coff: PeCoffHeader, opt: PeOptionalHeader, sections: typing.List[PeSection]
):
file.write(b"MZ")
file.seek(0x3C, io.SEEK_SET)
file.write(PE_OFFSET.to_bytes(2, byteorder="little"))
file.seek(PE_OFFSET, io.SEEK_SET)
file.write(PE_MAGIC)
file.write(coff)
file.write(opt)
offset = opt.SizeOfHeaders
for pe_s in sorted(sections, key=lambda s: s.VirtualAddress):
if pe_s.VirtualAddress < opt.SizeOfHeaders:
raise RuntimeError(f"Section {pe_s.Name} overlapping PE headers.")
pe_s.PointerToRawData = offset
file.write(pe_s)
offset = align_to(offset + len(pe_s.data), FILE_ALIGNMENT)
assert file.tell() <= opt.SizeOfHeaders
for pe_s in sections:
file.seek(pe_s.PointerToRawData, io.SEEK_SET)
file.write(pe_s.data)
file.truncate(offset)
def elf2efi(args: argparse.Namespace):
elf = ELFFile(args.ELF)
if not elf.little_endian:
raise RuntimeError("ELF file is not little-endian.")
if elf["e_type"] not in ["ET_DYN", "ET_EXEC"]:
raise RuntimeError("Unsupported ELF type.")
pe_arch = {
"EM_386": 0x014C,
"EM_AARCH64": 0xAA64,
"EM_ARM": 0x01C2,
"EM_LOONGARCH": 0x6232 if elf.elfclass == 32 else 0x6264,
"EM_RISCV": 0x5032 if elf.elfclass == 32 else 0x5064,
"EM_X86_64": 0x8664,
}.get(elf["e_machine"])
if pe_arch is None:
raise RuntimeError(f"Unsupported ELF arch {elf['e_machine']}")
coff = PeCoffHeader()
opt = PeOptionalHeader32() if elf.elfclass == 32 else PeOptionalHeader32Plus()
# We relocate to a unique image base to reduce the chances for runtime relocation to occur.
base_name = pathlib.Path(args.PE.name).name.encode()
opt.ImageBase = int(hashlib.sha1(base_name).hexdigest()[0:8], 16)
if elf.elfclass == 32:
opt.ImageBase = (0x400000 + opt.ImageBase) & 0xFFFF0000
else:
opt.ImageBase = (0x100000000 + opt.ImageBase) & 0x1FFFF0000
sections = convert_sections(elf, opt)
copy_sections(elf, opt, args.copy_sections, sections)
pe_reloc_s = convert_elf_relocations(elf, opt, sections, args.minimum_sections)
coff.Machine = pe_arch
coff.NumberOfSections = len(sections)
coff.TimeDateStamp = int(os.environ.get("SOURCE_DATE_EPOCH", time.time()))
coff.SizeOfOptionalHeader = sizeof(opt)
# EXECUTABLE_IMAGE|LINE_NUMS_STRIPPED|LOCAL_SYMS_STRIPPED|DEBUG_STRIPPED
# and (32BIT_MACHINE or LARGE_ADDRESS_AWARE)
coff.Characteristics = 0x30E if elf.elfclass == 32 else 0x22E
opt.SectionAlignment = SECTION_ALIGNMENT
opt.FileAlignment = FILE_ALIGNMENT
opt.MajorImageVersion = args.version_major
opt.MinorImageVersion = args.version_minor
opt.MajorSubsystemVersion = args.efi_major
opt.MinorSubsystemVersion = args.efi_minor
opt.Subsystem = args.subsystem
opt.Magic = 0x10B if elf.elfclass == 32 else 0x20B
opt.SizeOfImage = next_section_address(sections)
# DYNAMIC_BASE|NX_COMPAT|HIGH_ENTROPY_VA or DYNAMIC_BASE|NX_COMPAT
opt.DllCharacteristics = 0x160 if elf.elfclass == 64 else 0x140
# These values are taken from a natively built PE binary (although, unused by EDK2/EFI).
opt.SizeOfStackReserve = 0x100000
opt.SizeOfStackCommit = 0x001000
opt.SizeOfHeapReserve = 0x100000
opt.SizeOfHeapCommit = 0x001000
opt.NumberOfRvaAndSizes = N_DATA_DIRECTORY_ENTRIES
if pe_reloc_s:
opt.BaseRelocationTable = PeDataDirectory(
pe_reloc_s.VirtualAddress, pe_reloc_s.VirtualSize
)
write_pe(args.PE, coff, opt, sections)
def main():
parser = argparse.ArgumentParser(description="Convert ELF binaries to PE/EFI")
parser.add_argument(
"--version-major",
type=int,
default=0,
help="Major image version of EFI image",
)
parser.add_argument(
"--version-minor",
type=int,
default=0,
help="Minor image version of EFI image",
)
parser.add_argument(
"--efi-major",
type=int,
default=0,
help="Minimum major EFI subsystem version",
)
parser.add_argument(
"--efi-minor",
type=int,
default=0,
help="Minimum minor EFI subsystem version",
)
parser.add_argument(
"--subsystem",
type=int,
default=10,
help="PE subsystem",
)
parser.add_argument(
"ELF",
type=argparse.FileType("rb"),
help="Input ELF file",
)
parser.add_argument(
"PE",
type=argparse.FileType("wb"),
help="Output PE/EFI file",
)
parser.add_argument(
"--minimum-sections",
type=int,
default=0,
help="Minimum number of sections to leave space for",
)
parser.add_argument(
"--copy-sections",
type=str,
default="",
help="Copy these sections if found",
)
elf2efi(parser.parse_args())
if __name__ == "__main__":
main()
|