LZMA compressed debug symbols can often be found in binaries (particularly CentOS, to my experience), in the .gnu_debugdata segment. The ability to support these would expand the capabilities of retrowrite greatly, though it doesn't seem that I don't believe elftools has support for the .gnu_debugdata segment. Anyhow, as seen in the screenshot attached, this provides almost full debug info for a binary once parsed -- the issue is, of course, de-compressing the symbols and applying them. I'm not the greatest Python developer (I've started thinking more in C than in Python), so I leave this as a suggestion/feature request.
An example from the readelf tool.
[user@CentOS-F5 bin]$ readelf -e telnet
ELF Header:
Magic: 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00
Class: ELF64
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: DYN (Shared object file)
Machine: Advanced Micro Devices X86-64
Version: 0x1
Entry point address: 0x4b19
Start of program headers: 64 (bytes into file)
Start of section headers: 99912 (bytes into file)
Flags: 0x0
Size of this header: 64 (bytes)
Size of program headers: 56 (bytes)
Number of program headers: 9
Size of section headers: 64 (bytes)
Number of section headers: 29
Section header string table index: 28
Section Headers:
[Nr] Name Type Address Offset
Size EntSize Flags Link Info Align
[ 0] NULL 0000000000000000 00000000
0000000000000000 0000000000000000 0 0 0
[ 1] .interp PROGBITS 0000000000000238 00000238
000000000000001c 0000000000000000 A 0 0 1
[ 2] .note.ABI-tag NOTE 0000000000000254 00000254
0000000000000020 0000000000000000 A 0 0 4
[ 3] .note.gnu.bu[...] NOTE 0000000000000274 00000274
0000000000000024 0000000000000000 A 0 0 4
[ 4] .gnu.hash GNU_HASH 0000000000000298 00000298
0000000000000038 0000000000000000 A 5 0 8
[ 5] .dynsym DYNSYM 00000000000002d0 000002d0
00000000000009f0 0000000000000018 A 6 2 8
[ 6] .dynstr STRTAB 0000000000000cc0 00000cc0
0000000000000421 0000000000000000 A 0 0 1
[ 7] .gnu.version VERSYM 00000000000010e2 000010e2
00000000000000d4 0000000000000002 A 5 0 2
[ 8] .gnu.version_r VERNEED 00000000000011b8 000011b8
0000000000000080 0000000000000000 A 6 1 8
[ 9] .rela.dyn RELA 0000000000001238 00001238
0000000000002748 0000000000000018 A 5 0 8
[10] .rela.plt RELA 0000000000003980 00003980
0000000000000828 0000000000000018 AI 5 12 8
[11] .init PROGBITS 00000000000041a8 000041a8
000000000000001a 0000000000000000 AX 0 0 4
[12] .plt PROGBITS 00000000000041d0 000041d0
0000000000000580 0000000000000010 AX 0 0 16
[13] .text PROGBITS 0000000000004750 00004750
000000000000bad2 0000000000000000 AX 0 0 16
[14] .fini PROGBITS 0000000000010224 00010224
0000000000000009 0000000000000000 AX 0 0 4
[15] .rodata PROGBITS 0000000000010230 00010230
0000000000002cb0 0000000000000000 A 0 0 8
[16] .eh_frame_hdr PROGBITS 0000000000012ee0 00012ee0
00000000000005a4 0000000000000000 A 0 0 4
[17] .eh_frame PROGBITS 0000000000013488 00013488
0000000000001ef4 0000000000000000 A 0 0 8
[18] .init_array INIT_ARRAY 0000000000215a90 00015a90
0000000000000008 0000000000000000 WA 0 0 8
[19] .fini_array FINI_ARRAY 0000000000215a98 00015a98
0000000000000008 0000000000000000 WA 0 0 8
[20] .jcr PROGBITS 0000000000215aa0 00015aa0
0000000000000008 0000000000000000 WA 0 0 8
[21] .data.rel.ro PROGBITS 0000000000215aa8 00015aa8
0000000000000008 0000000000000000 WA 0 0 8
[22] .dynamic DYNAMIC 0000000000215ab0 00015ab0
0000000000000220 0000000000000010 WA 6 0 8
[23] .got PROGBITS 0000000000215cd0 00015cd0
0000000000000330 0000000000000008 WA 0 0 8
[24] .data PROGBITS 0000000000216000 00016000
0000000000001ac8 0000000000000000 WA 0 0 32
[25] .bss NOBITS 0000000000217ae0 00017ac8
000000000000cf48 0000000000000000 WA 0 0 32
[26] .gnu_debuglink PROGBITS 0000000000000000 00017ac8
0000000000000014 0000000000000000 0 0 4
[27] .gnu_debugdata PROGBITS 0000000000000000 00017adc
0000000000000a58 0000000000000000 0 0 1
[28] .shstrtab STRTAB 0000000000000000 00018534
0000000000000111 0000000000000000 0 0 1
Key to Flags:
W (write), A (alloc), X (execute), M (merge), S (strings), I (info),
L (link order), O (extra OS processing required), G (group), T (TLS),
C (compressed), x (unknown), o (OS specific), E (exclude),
D (mbind), l (large), p (processor specific)
Program Headers:
Type Offset VirtAddr PhysAddr
FileSiz MemSiz Flags Align
PHDR 0x0000000000000040 0x0000000000000040 0x0000000000000040
0x00000000000001f8 0x00000000000001f8 R E 0x8
INTERP 0x0000000000000238 0x0000000000000238 0x0000000000000238
0x000000000000001c 0x000000000000001c R 0x1
[Requesting program interpreter: /lib64/ld-linux-x86-64.so.2]
LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000
0x000000000001537c 0x000000000001537c R E 0x200000
LOAD 0x0000000000015a90 0x0000000000215a90 0x0000000000215a90
0x0000000000002038 0x000000000000ef98 RW 0x200000
DYNAMIC 0x0000000000015ab0 0x0000000000215ab0 0x0000000000215ab0
0x0000000000000220 0x0000000000000220 RW 0x8
NOTE 0x0000000000000254 0x0000000000000254 0x0000000000000254
0x0000000000000044 0x0000000000000044 R 0x4
GNU_EH_FRAME 0x0000000000012ee0 0x0000000000012ee0 0x0000000000012ee0
0x00000000000005a4 0x00000000000005a4 R 0x4
GNU_STACK 0x0000000000000000 0x0000000000000000 0x0000000000000000
0x0000000000000000 0x0000000000000000 RW 0x10
GNU_RELRO 0x0000000000015a90 0x0000000000215a90 0x0000000000215a90
0x0000000000000570 0x0000000000000570 R 0x1
Section to Segment mapping:
Segment Sections...
00
01 .interp
02 .interp .note.ABI-tag .note.gnu.build-id .gnu.hash .dynsym .dynstr .gnu.version .gnu.version_r .rela.dyn .rela.plt .init .plt .text .fini .rodata .eh_frame_hdr .eh_frame
03 .init_array .fini_array .jcr .data.rel.ro .dynamic .got .data .bss
04 .dynamic
05 .note.ABI-tag .note.gnu.build-id
06 .eh_frame_hdr
07
08 .init_array .fini_array .jcr .data.rel.ro .dynamic .got
As you'll see from the readelf output, there also exists the issue of lacking a proper section-to-segment mapping for .gnu_debugdata. I believe the issue may be able to be solved with a fork of PyELFTools, though that's up to you all as it would complicate installation.
Initial reference: https://sourceware.org/gdb/onlinedocs/gdb/MiniDebugInfo.html
LZMA compressed debug symbols can often be found in binaries (particularly CentOS, to my experience), in the .gnu_debugdata segment. The ability to support these would expand the capabilities of retrowrite greatly, though it doesn't seem that I don't believe
elftoolshas support for the .gnu_debugdata segment. Anyhow, as seen in the screenshot attached, this provides almost full debug info for a binary once parsed -- the issue is, of course, de-compressing the symbols and applying them. I'm not the greatest Python developer (I've started thinking more in C than in Python), so I leave this as a suggestion/feature request.An example from the
readelftool.As you'll see from the
readelfoutput, there also exists the issue of lacking a proper section-to-segment mapping for .gnu_debugdata. I believe the issue may be able to be solved with a fork of PyELFTools, though that's up to you all as it would complicate installation.Regards,
impost0r