Pirms dažÄm dienÄm es nolÄmu mainÄ«t marÅ”rutÄtÄja programmaparatÅ«ru, izmantojot binwalk.
Es pats nopirku
Katru reizi, kad es pÄrku jaunu marÅ”rutÄtÄju, es instalÄju
PÄc OpenWRT lejupielÄdes es arÄ«
Kas ir binwalk?
2010. gadÄ izveidojis Kreigs Hefners, binwalk var skenÄt programmaparatÅ«ras attÄlus un atrast failus, identificÄt un izvilkt failu sistÄmas attÄlus, izpildÄmo kodu, saspiestus arhÄ«vus, sÄknÄÅ”anas programmas un kodolus, failu formÄtus, piemÄram, JPEG un PDF, un daudz ko citu.
Varat izmantot binwalk, lai apgrieztu programmaparatÅ«ru, lai saprastu, kÄ tÄ darbojas. MeklÄjiet binÄrajos failos ievainojamÄ«bas, izÅemiet failus un meklÄjiet aizmugures durvis vai digitÄlos sertifikÄtus. JÅ«s varat arÄ« atrast opcodes
par virkni dažÄdu CPU.
Varat izvilkt failu sistÄmas attÄlus, lai meklÄtu konkrÄtus paroļu failus (passwd, shadow utt.) un mÄÄ£inÄtu izjaukt paroļu jaucÄjus. Varat veikt binÄro parsÄÅ”anu starp diviem vai vairÄkiem failiem. Varat veikt datu entropijas analÄ«zi, lai meklÄtu saspiestus datus vai kodÄtas Å”ifrÄÅ”anas atslÄgas. Tas viss bez nepiecieÅ”amÄ«bas piekļūt avota kodam.
VispÄr viss nepiecieÅ”amais ir :)
KÄ darbojas binwalk?
Binwalk galvenÄ iezÄ«me ir tÄ parakstu skenÄÅ”ana. Binwalk var skenÄt programmaparatÅ«ras attÄlu, lai meklÄtu dažÄdus iebÅ«vÄtos failu tipus un failu sistÄmas.
Vai jÅ«s zinÄt komandrindas utilÄ«tu file
?
file /bin/bash
/bin/bash: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/l, for GNU/Linux 3.2.0, BuildID[sha1]=12f73d7a8e226c663034529c8dd20efec22dde54, stripped
Komanda file
aplÅ«ko faila galveni un meklÄ parakstu (maÄ£isko numuru), lai noteiktu faila tipu. PiemÄram, ja fails sÄkas ar baitu secÄ«bu 0x89 0x50 0x4E 0x47 0x0D 0x0A 0x1A 0x0A
, tas zina, ka tas ir PNG fails. IeslÄgts
Binwalk darbojas tÄpat. Bet tÄ vietÄ, lai meklÄtu parakstus tikai faila sÄkumÄ, binwalk skenÄs visu failu. TurklÄt binwalk var izvilkt attÄlÄ atrodamos failus.
Darbarīki file
Šø binwalk
izmantot bibliotÄku libmagic
lai identificÄtu failu parakstus. Bet binwalk
papildus atbalsta pielÄgotu maÄ£isko parakstu sarakstu, lai meklÄtu saspiestus/zip failus, programmaparatÅ«ras galvenes, Linux kodolus, sÄknÄÅ”anas ielÄdÄtÄjus, failu sistÄmas un tÄ tÄlÄk.
IzklaidÄsimies?
Binwalk uzstÄdÄ«Å”ana
Binwalk tiek atbalstÄ«ts vairÄkÄs platformÄs, tostarp Linux, OSX, FreeBSD un Windows.
Lai instalÄtu jaunÄko binwalk versiju, varat
Binwalk ir daudz dažÄdu parametru:
$ binwalk
Binwalk v2.2.0
Craig Heffner, ReFirmLabs
https://github.com/ReFirmLabs/binwalk
Usage: binwalk [OPTIONS] [FILE1] [FILE2] [FILE3] ...
Signature Scan Options:
-B, --signature Scan target file(s) for common file signatures
-R, --raw=<str> Scan target file(s) for the specified sequence of bytes
-A, --opcodes Scan target file(s) for common executable opcode signatures
-m, --magic=<file> Specify a custom magic file to use
-b, --dumb Disable smart signature keywords
-I, --invalid Show results marked as invalid
-x, --exclude=<str> Exclude results that match <str>
-y, --include=<str> Only show results that match <str>
Extraction Options:
-e, --extract Automatically extract known file types
-D, --dd=<type:ext:cmd> Extract <type> signatures, give the files an extension of <ext>, and execute <cmd>
-M, --matryoshka Recursively scan extracted files
-d, --depth=<int> Limit matryoshka recursion depth (default: 8 levels deep)
-C, --directory=<str> Extract files/folders to a custom directory (default: current working directory)
-j, --size=<int> Limit the size of each extracted file
-n, --count=<int> Limit the number of extracted files
-r, --rm Delete carved files after extraction
-z, --carve Carve data from files, but don't execute extraction utilities
-V, --subdirs Extract into sub-directories named by the offset
Entropy Options:
-E, --entropy Calculate file entropy
-F, --fast Use faster, but less detailed, entropy analysis
-J, --save Save plot as a PNG
-Q, --nlegend Omit the legend from the entropy plot graph
-N, --nplot Do not generate an entropy plot graph
-H, --high=<float> Set the rising edge entropy trigger threshold (default: 0.95)
-L, --low=<float> Set the falling edge entropy trigger threshold (default: 0.85)
Binary Diffing Options:
-W, --hexdump Perform a hexdump / diff of a file or files
-G, --green Only show lines containing bytes that are the same among all files
-i, --red Only show lines containing bytes that are different among all files
-U, --blue Only show lines containing bytes that are different among some files
-u, --similar Only display lines that are the same between all files
-w, --terse Diff all files, but only display a hex dump of the first file
Raw Compression Options:
-X, --deflate Scan for raw deflate compression streams
-Z, --lzma Scan for raw LZMA compression streams
-P, --partial Perform a superficial, but faster, scan
-S, --stop Stop after the first result
General Options:
-l, --length=<int> Number of bytes to scan
-o, --offset=<int> Start scan at this file offset
-O, --base=<int> Add a base address to all printed offsets
-K, --block=<int> Set file block size
-g, --swap=<int> Reverse every n bytes before scanning
-f, --log=<file> Log results to file
-c, --csv Log results to file in CSV format
-t, --term Format output to fit the terminal window
-q, --quiet Suppress output to stdout
-v, --verbose Enable verbose output
-h, --help Show help output
-a, --finclude=<str> Only scan files whose names match this regex
-p, --fexclude=<str> Do not scan files whose names match this regex
-s, --status=<int> Enable the status server on the specified port
AttÄlu skenÄÅ”ana
SÄksim, meklÄjot faila parakstus attÄla iekÅ”pusÄ (attÄls no vietnes
Binwalk palaiŔana ar parametru --signature:
$ binwalk --signature --term archer-c7.bin
DECIMAL HEXADECIMAL DESCRIPTION
------------------------------------------------------------------------------------------
21876 0x5574 U-Boot version string, "U-Boot 1.1.4-g4480d5f9-dirty (May
20 2019 - 18:45:16)"
21940 0x55B4 CRC32 polynomial table, big endian
23232 0x5AC0 uImage header, header size: 64 bytes, header CRC:
0x386C2BD5, created: 2019-05-20 10:45:17, image size:
41162 bytes, Data Address: 0x80010000, Entry Point:
0x80010000, data CRC: 0xC9CD1E38, OS: Linux, CPU: MIPS,
image type: Firmware Image, compression type: lzma, image
name: "u-boot image"
23296 0x5B00 LZMA compressed data, properties: 0x5D, dictionary size:
8388608 bytes, uncompressed size: 97476 bytes
64968 0xFDC8 XML document, version: "1.0"
78448 0x13270 uImage header, header size: 64 bytes, header CRC:
0x78A267FF, created: 2019-07-26 07:46:14, image size:
1088500 bytes, Data Address: 0x80060000, Entry Point:
0x80060000, data CRC: 0xBB9D4F94, OS: Linux, CPU: MIPS,
image type: Multi-File Image, compression type: lzma,
image name: "MIPS OpenWrt Linux-3.3.8"
78520 0x132B8 LZMA compressed data, properties: 0x6D, dictionary size:
8388608 bytes, uncompressed size: 3164228 bytes
1167013 0x11CEA5 Squashfs filesystem, little endian, version 4.0,
compression:xz, size: 14388306 bytes, 2541 inodes,
blocksize: 65536 bytes, created: 2019-07-26 07:51:38
15555328 0xED5B00 gzip compressed data, from Unix, last modified: 2019-07-26
07:51:41
Tagad mums ir daudz informÄcijas par Å”o attÄlu.
AttÄlu izmantoÅ”ana 0x5AC0
un saspiests sÄknÄÅ”anas ielÄdes attÄls vietnÄ 0x5B00
). Pamatojoties uz uImage galveni 0x13270, mÄs zinÄm, ka procesora arhitektÅ«ra ir MIPS un Linux kodola versija ir 3.3.8. Un pÄc adresÄ atrastÄ attÄla 0x11CEA5
, mÄs to varam redzÄt rootfs
ir failu sistÄma squashfs
.
Tagad izÅemsim sÄknÄÅ”anas ielÄdÄtÄju (U-Boot), izmantojot komandu dd
:
$ dd if=archer-c7.bin of=u-boot.bin.lzma bs=1 skip=23296 count=41162
41162+0 records in
41162+0 records out
41162 bytes (41 kB, 40 KiB) copied, 0,0939608 s, 438 kB/s
TÄ kÄ attÄls ir saspiests, izmantojot LZMA, mums tas ir jÄatspiež:
$ unlzma u-boot.bin.lzma
Tagad mums ir U-Boot attÄls:
$ ls -l u-boot.bin
-rw-rw-r-- 1 sprado sprado 97476 Fev 5 08:48 u-boot.bin
KÄ bÅ«tu ar noklusÄjuma vÄrtÄ«bas atraÅ”anu bootargs
?
$ strings u-boot.bin | grep bootargs
bootargs
bootargs=console=ttyS0,115200 board=AP152 rootfstype=squashfs init=/etc/preinit mtdparts=spi0.0:128k(factory-uboot),192k(u-boot),64k(ART),1536k(uImage),14464k@0x1e0000(rootfs) mem=128M
U-boot vides mainīgais bootargs
izmanto parametru nodoÅ”anai Linux kodolam. Un no iepriekÅ” minÄtÄ mÄs labÄk izprotam ierÄ«ces zibatmiÅu.
KÄ bÅ«tu ar Linux kodola attÄla izvilkÅ”anu?
$ dd if=archer-c7.bin of=uImage bs=1 skip=78448 count=1088572
1088572+0 records in
1088572+0 records out
1088572 bytes (1,1 MB, 1,0 MiB) copied, 1,68628 s, 646 kB/s
MÄs varam pÄrbaudÄ«t, vai attÄls ir veiksmÄ«gi izvilkts, izmantojot komandu file
:
$ file uImage
uImage: u-boot legacy uImage, MIPS OpenWrt Linux-3.3.8, Linux/MIPS, Multi-File Image (lzma), 1088500 bytes, Fri Jul 26 07:46:14 2019, Load Address: 0x80060000, Entry Point: 0x80060000, Header CRC: 0x78A267FF, Data CRC: 0xBB9D4F94
uImage faila formÄts bÅ«tÄ«bÄ ir Linux kodola attÄls ar papildu galveni. NoÅemsim Å”o galveni, lai iegÅ«tu galÄ«go Linux kodola attÄlu:
$ dd if=uImage of=Image.lzma bs=1 skip=72
1088500+0 records in
1088500+0 records out
1088500 bytes (1,1 MB, 1,0 MiB) copied, 1,65603 s, 657 kB/s
AttÄls ir saspiests, tÄpÄc izpakosim to:
$ unlzma Image.lzma
Tagad mums ir Linux kodola attÄls:
$ ls -la Image
-rw-rw-r-- 1 sprado sprado 3164228 Fev 5 10:51 Image
Ko mÄs varam darÄ«t ar kodola attÄlu? MÄs varÄtu, piemÄram, veikt virknes meklÄÅ”anu attÄlÄ un atrast Linux kodola versiju un uzzinÄt par vidi, kas izmantota kodola izveidei:
$ strings Image | grep "Linux version"
Linux version 3.3.8 (leo@leo-MS-7529) (gcc version 4.6.3 20120201 (prerelease) (Linaro GCC 4.6-2012.02) ) #1 Mon May 20 18:53:02 CST 2019
Lai gan programmaparatÅ«ra tika izlaista pagÄjuÅ”ajÄ gadÄ (2019. gadÄ), rakstot Å”o rakstu, tÄ izmanto veco Linux kodola versiju (3.3.8), kas tika izlaista 2012. gadÄ, kas kompilÄta ar ļoti vecu GCC versiju (4.6) arÄ« kopÅ” 2012. gada. !
(aptuveni tulk. vai joprojÄm uzticaties marÅ”rutÄtÄjiem birojÄ un mÄjÄs?)
Ar opciju --opcodes
mÄs varam arÄ« izmantot binwalk, lai meklÄtu maŔīnas instrukcijas un noteiktu attÄla procesora arhitektÅ«ru:
$ binwalk --opcodes Image
DECIMAL HEXADECIMAL DESCRIPTION
--------------------------------------------------------------------------------
2400 0x960 MIPS instructions, function epilogue
2572 0xA0C MIPS instructions, function epilogue
2828 0xB0C MIPS instructions, function epilogue
KÄ ar saknes failu sistÄmu? TÄ vietÄ, lai manuÄli izvilktu attÄlu, izmantosim opciju binwalk --extract
:
$ binwalk --extract --quiet archer-c7.bin
Visa saknes failu sistÄma tiks izvilkta apakÅ”direktorijÄ:
$ cd _archer-c7.bin.extracted/squashfs-root/
$ ls
bin dev etc lib mnt overlay proc rom root sbin sys tmp usr var www
$ cat etc/banner
MM NM MMMMMMM M M
$MMMMM MMMMM MMMMMMMMMMM MMM MMM
MMMMMMMM MM MMMMM. MMMMM:MMMMMM: MMMM MMMMM
MMMM= MMMMMM MMM MMMM MMMMM MMMM MMMMMM MMMM MMMMM'
MMMM= MMMMM MMMM MM MMMMM MMMM MMMM MMMMNMMMMM
MMMM= MMMM MMMMM MMMMM MMMM MMMM MMMMMMMM
MMMM= MMMM MMMMMM MMMMM MMMM MMMM MMMMMMMMM
MMMM= MMMM MMMMM, NMMMMMMMM MMMM MMMM MMMMMMMMMMM
MMMM= MMMM MMMMMM MMMMMMMM MMMM MMMM MMMM MMMMMM
MMMM= MMMM MM MMMM MMMM MMMM MMMM MMMM MMMM
MMMM$ ,MMMMM MMMMM MMMM MMM MMMM MMMMM MMMM MMMM
MMMMMMM: MMMMMMM M MMMMMMMMMMMM MMMMMMM MMMMMMM
MMMMMM MMMMN M MMMMMMMMM MMMM MMMM
MMMM M MMMMMMM M M
M
---------------------------------------------------------------
For those about to rock... (%C, %R)
---------------------------------------------------------------
Tagad mÄs varam darÄ«t daudz dažÄdu lietu.
MÄs varam meklÄt konfigurÄcijas failus, paroļu jaucÄjus, kriptogrÄfiskÄs atslÄgas un digitÄlos sertifikÄtus. MÄs varam analizÄt binÄros failus
Ar
$ ls
bin dev etc lib mnt overlay proc rom root sbin sys tmp usr var www
$ cp /usr/bin/qemu-mips-static .
$ sudo chroot . ./qemu-mips-static bin/busybox
BusyBox v1.19.4 (2019-05-20 18:13:49 CST) multi-call binary.
Copyright (C) 1998-2011 Erik Andersen, Rob Landley, Denys Vlasenko
and others. Licensed under GPLv2.
See source distribution for full notice.
Usage: busybox [function] [arguments]...
or: busybox --list[-full]
or: function [arguments]...
BusyBox is a multi-call binary that combines many common Unix
utilities into a single executable. Most people will create a
link to busybox for each function they wish to use and BusyBox
will act like whatever it was invoked as.
Currently defined functions:
[, [[, addgroup, adduser, arping, ash, awk, basename, cat, chgrp, chmod, chown, chroot, clear, cmp, cp, crond, crontab, cut, date, dd, delgroup, deluser, dirname, dmesg, echo, egrep, env, expr, false,
fgrep, find, free, fsync, grep, gunzip, gzip, halt, head, hexdump, hostid, id, ifconfig, init, insmod, kill, killall, klogd, ln, lock, logger, ls, lsmod, mac_addr, md5sum, mkdir, mkfifo, mknod, mktemp,
mount, mv, nice, passwd, pgrep, pidof, ping, ping6, pivot_root, poweroff, printf, ps, pwd, readlink, reboot, reset, rm, rmdir, rmmod, route, sed, seq, sh, sleep, sort, start-stop-daemon, strings,
switch_root, sync, sysctl, tail, tar, tee, telnet, test, tftp, time, top, touch, tr, traceroute, true, udhcpc, umount, uname, uniq, uptime, vconfig, vi, watchdog, wc, wget, which, xargs, yes, zcat
Lieliski! Bet, lÅ«dzu, Åemiet vÄrÄ, ka BusyBox versija ir 1.19.4. Å Ä« ir ļoti veca BusyBox versija, izlaists 2012. gada aprÄ«lÄ«.
TÄtad TP-Link izlaiž programmaparatÅ«ras attÄlu 2019. gadÄ, izmantojot programmatÅ«ru (GCC rÄ«kÄ·Ädi, kodolu, BusyBox u.c.) no 2012. gada!
Tagad jÅ«s saprotat, kÄpÄc es vienmÄr instalÄju OpenWRT savos marÅ”rutÄtÄjos?
Tas vÄl nav viss
Binwalk var arÄ« veikt entropijas analÄ«zi, izdrukÄt neapstrÄdÄtus entropijas datus un Ä£enerÄt entropijas grafikus. Parasti lielÄka entropija tiek novÄrota, ja attÄla baiti ir nejauÅ”i. Tas var nozÄ«mÄt, ka attÄlÄ ir Å”ifrÄts, saspiests vai neskaidrs fails. CietÄ Å”ifrÄÅ”anas atslÄga? KÄpÄc ne.
MÄs varam izmantot arÄ« parametru --raw
lai attÄlÄ vai parametrÄ atrastu pielÄgotu neapstrÄdÄtu baitu secÄ«bu --hexdump
lai veiktu hex dump, salÄ«dzinot divus vai vairÄkus ievades failus.
--magic
, vai pievienojot tos direktorijam $ HOME / .config / binwalk / magic
.
PlaÅ”Äku informÄciju par binwalk varat atrast vietnÄ
binwalk paplaÅ”inÄjums
Tur
import binwalk
binwalk.scan()
Izmantojot Python API, varat arī izveidot
PastÄv arÄ«
KÄpÄc gan nelejupielÄdÄt programmaparatÅ«ras attÄlu no interneta un neizmÄÄ£inÄt binwalk? Es apsolu, ka tev bÅ«s ļoti jautri :)
Avots: www.habr.com