2.2.1 Radare2
简介
IDA Pro 昂贵的价格令很多二进制爱好者望而却步,于是在开源世界中催生出了一个新的逆向工程框架——Radare2,它拥有非常强大的功能,包括反汇编、调试、打补丁、虚拟化等等,而且可以运行在几乎所有的主流平台上(GNU/Linux、Windows、BSD、iOS、OSX……)。Radare2 开发之初仅提供了基于命令行的操作,尽管现在也有非官方的GUI,但我更喜欢直接在终端上运行它,当然这也就意味着更高陡峭的学习曲线。Radare2 是由一系列的组件构成的,这些组件赋予了 Radare2 强大的分析能力,可以在 Radare2 中或者单独被使用。
这里是 Radare2 与其他二进制分析工具的对比。(Comparison Table)
安装
$ git clone https://github.com/radare/radare2.git
$ cd radare2
$ ./sys/install.sh
更新
$ ./sys/install.sh
卸载
$ make uninstall
$ make purge
命令行使用方法
Radare2 在命令行下有一些小工具可供使用:
- radare2:十六进制编辑器和调试器的核心,通常通过它进入交互式界面。
- rabin2:从可执行二进制文件中提取信息。
- rasm2:汇编和反汇编。
- rahash2:基于块的哈希工具。
- radiff2:二进制文件或代码差异比对。
- rafind2:查找字节模式。
- ragg2:r_egg 的前端,将高级语言编写的简单程序编译成x86、x86-64和ARM的二进制文件。
- rarun2:用于在不同环境中运行程序。
- rax2:数据格式转换。
radare2/r2
$ r2 -h
Usage: r2 [-ACdfLMnNqStuvwzX] [-P patch] [-p prj] [-a arch] [-b bits] [-i file]
[-s addr] [-B baddr] [-M maddr] [-c cmd] [-e k=v] file|pid|-|--|=
-- run radare2 without opening any file
- same as 'r2 malloc://512'
= read file from stdin (use -i and -c to run cmds)
-= perform !=! command to run all commands remotely
-0 print \x00 after init and every command
-a [arch] set asm.arch
-A run 'aaa' command to analyze all referenced code
-b [bits] set asm.bits
-B [baddr] set base address for PIE binaries
-c 'cmd..' execute radare command
-C file is host:port (alias for -c+=http://%s/cmd/)
-d debug the executable 'file' or running process 'pid'
-D [backend] enable debug mode (e cfg.debug=true)
-e k=v evaluate config var
-f block size = file size
-F [binplug] force to use that rbin plugin
-h, -hh show help message, -hh for long
-H ([var]) display variable
-i [file] run script file
-I [file] run script file before the file is opened
-k [k=v] perform sdb query into core->sdb
-l [lib] load plugin file
-L list supported IO plugins
-m [addr] map file at given address (loadaddr)
-M do not demangle symbol names
-n, -nn do not load RBin info (-nn only load bin structures)
-N do not load user settings and scripts
-o [OS/kern] set asm.os (linux, macos, w32, netbsd, ...)
-q quiet mode (no prompt) and quit after -i
-p [prj] use project, list if no arg, load if no file
-P [file] apply rapatch file and quit
-R [rarun2] specify rarun2 profile to load (same as -e dbg.profile=X)
-s [addr] initial seek
-S start r2 in sandbox mode
-t load rabin2 info in thread
-u set bin.filter=false to get raw sym/sec/cls names
-v, -V show radare2 version (-V show lib versions)
-w open file in write mode
-X [rr2rule] specify custom rarun2 directive
-z, -zz do not load strings or load them even in raw
参数很多,这里最重要是 file
。如果你想 attach 到一个进程上,则使用 pid
。常用参数如下:
-A
:相当于在交互界面输入了aaa
。-c
:运行 radare 命令。(r2 -A -q -c 'iI~pic' file
)-d
:调试二进制文件或进程。-a
,-b
,-o
:分别指定体系结构、位数和操作系统,通常是自动的,但也可以手动指定。-w
:使用可写模式打开。
rabin2
$ rabin2 -h
Usage: rabin2 [-AcdeEghHiIjlLMqrRsSvVxzZ] [-@ at] [-a arch] [-b bits] [-B addr]
[-C F:C:D] [-f str] [-m addr] [-n str] [-N m:M] [-P[-P] pdb]
[-o str] [-O str] [-k query] [-D lang symname] | file
-@ [addr] show section, symbol or import at addr
-A list sub-binaries and their arch-bits pairs
-a [arch] set arch (x86, arm, .. or <arch>_<bits>)
-b [bits] set bits (32, 64 ...)
-B [addr] override base address (pie bins)
-c list classes
-C [fmt:C:D] create [elf,mach0,pe] with Code and Data hexpairs (see -a)
-d show debug/dwarf information
-D lang name demangle symbol name (-D all for bin.demangle=true)
-e entrypoint
-E globally exportable symbols
-f [str] select sub-bin named str
-F [binfmt] force to use that bin plugin (ignore header check)
-g same as -SMZIHVResizcld (show all info)
-G [addr] load address . offset to header
-h this help message
-H header fields
-i imports (symbols imported from libraries)
-I binary info
-j output in json
-k [sdb-query] run sdb query. for example: '*'
-K [algo] calculate checksums (md5, sha1, ..)
-l linked libraries
-L [plugin] list supported bin plugins or plugin details
-m [addr] show source line at addr
-M main (show address of main symbol)
-n [str] show section, symbol or import named str
-N [min:max] force min:max number of chars per string (see -z and -zz)
-o [str] output file/folder for write operations (out by default)
-O [str] write/extract operations (-O help)
-p show physical addresses
-P show debug/pdb information
-PP download pdb file for binary
-q be quiet, just show fewer data
-qq show less info (no offset/size for -z for ex.)
-Q show load address used by dlopen (non-aslr libs)
-r radare output
-R relocations
-s symbols
-S sections
-u unfiltered (no rename duplicated symbols/sections)
-v display version and quit
-V Show binary version information
-x extract bins contained in file
-X [fmt] [f] .. package in fat or zip the given files and bins contained in file
-z strings (from data section)
-zz strings (from raw bins [e bin.rawstr=1])
-zzz dump raw strings to stdout (for huge files)
-Z guess size of binary program
当我们拿到一个二进制文件时,第一步就是获取关于它的基本信息,这时候就可以使用 rabin2。rabin2 可以获取包括 ELF、PE、Mach-O、Java CLASS 文件的区段、头信息、导入导出表、数据段字符串、入口点等信息,并且支持多种格式的输出。
下面介绍一些常见的用法:(我还会列出其他实现类似功能工具的用法,你可以对比一下它们的输出)
-I
:最常用的参数,它可以打印出二进制文件信息,其中我们需要重点关注其使用的安全防护技术,如 canary、pic、nx 等。(file
、chekcsec -f
)-e
:得到二进制文件的入口点。(`readelf -h`)-i
:获得导入符号表,RLT中的偏移等。(readelf -r
)-E
:获得全局导出符号表。-s
:获得符号表。(readelf -s
)-l
:获得二进制文件使用到的动态链接库。(ldd
)-z
:从 ELF 文件的 .rodare 段或 PE 文件的 .text 中获得字符串。(strings -d
)-S
:获得完整的段信息。(readelf -S
)-c
:列出所有类,在分析 Java 程序是很有用。
最后还要提到的一个参数 -r
,它可以将我们得到的信息以 radare2 可读的形式输出,在后续的分析中可以将这样格式的信息输入 radare2,这是非常有用的。
rasm2
$ rasm2 -h
Usage: rasm2 [-ACdDehLBvw] [-a arch] [-b bits] [-o addr] [-s syntax]
[-f file] [-F fil:ter] [-i skip] [-l len] 'code'|hex|-
-a [arch] Set architecture to assemble/disassemble (see -L)
-A Show Analysis information from given hexpairs
-b [bits] Set cpu register size (8, 16, 32, 64) (RASM2_BITS)
-c [cpu] Select specific CPU (depends on arch)
-C Output in C format
-d, -D Disassemble from hexpair bytes (-D show hexpairs)
-e Use big endian instead of little endian
-E Display ESIL expression (same input as in -d)
-f [file] Read data from file
-F [in:out] Specify input and/or output filters (att2intel, x86.pseudo, ...)
-h, -hh Show this help, -hh for long
-i [len] ignore/skip N bytes of the input buffer
-k [kernel] Select operating system (linux, windows, darwin, ..)
-l [len] Input/Output length
-L List Asm plugins: (a=asm, d=disasm, A=analyze, e=ESIL)
-o [offset] Set start address for code (default 0)
-O [file] Output file name (rasm2 -Bf a.asm -O a)
-p Run SPP over input for assembly
-s [syntax] Select syntax (intel, att)
-B Binary input/output (-l is mandatory for binary input)
-v Show version information
-w What's this instruction for? describe opcode
-q quiet mode
rasm2 是一个内联汇编、反汇编程序。它的主要功能是获取给定机器指令操作码对应的字节。
下面是一些重要的参数:
-L
:列出目标体系结构所支持的插件,输出中的第一列说明了插件提供的功能(a=asm, d=disasm, A=analyze, e=ESIL)。-a
:知道插件的名字后,就可以使用 -a` 来进行设置。-b
:设置CPU寄存器的位数。-d
:反汇编十六进制对字符串。-D
:反汇编并显示十六进制对和操作码。-C
:汇编后以 C 语言风格输出。-f
:从文件中读入汇编代码。
例子:
$ rasm2 -a x86 -b 32 'mov eax,30'
b81e000000
$ rasm2 -a x86 -b 32 'mov eax,30' -C
"\xb8\x1e\x00\x00\x00"
$ rasm2 -d b81e000000
mov eax, 0x1e
$ rasm2 -D b81e000000
0x00000000 5 b81e000000 mov eax, 0x1e
$ rasm2 -a x86 -b 32 -d 'b81e000000'
mov eax, 0x1e
$ cat a.asm
mov eax,30
$ rasm2 -f a.asm
b81e000000
rahash2
$ rahash2 -h
Usage: rahash2 [-rBhLkv] [-b S] [-a A] [-c H] [-E A] [-s S] [-f O] [-t O] [file] ...
-a algo comma separated list of algorithms (default is 'sha256')
-b bsize specify the size of the block (instead of full file)
-B show per-block hash
-c hash compare with this hash
-e swap endian (use little endian)
-E algo encrypt. Use -S to set key and -I to set IV
-D algo decrypt. Use -S to set key and -I to set IV
-f from start hashing at given address
-i num repeat hash N iterations
-I iv use give initialization vector (IV) (hexa or s:string)
-S seed use given seed (hexa or s:string) use ^ to prefix (key for -E)
(- will slurp the key from stdin, the @ prefix points to a file
-k show hash using the openssh's randomkey algorithm
-q run in quiet mode (-qq to show only the hash)
-L list all available algorithms (see -a)
-r output radare commands
-s string hash this string instead of files
-t to stop hashing at given address
-x hexstr hash this hexpair string instead of files
-v show version information
rahash2 用于计算检验和,支持字节流、文件、字符串等形式和多种算法。
重要参数:
-a
:指定算法。默认为 sha256,如果指定为 all,则使用所有算法。-b
:指定块的大小(而不是整个文件)-B
:打印处每个块的哈希-s
:指定字符串(而不是文件)-a entropy
:显示每个块的熵(-B -b 512 -a entropy
)
radiff2
$ radiff2 -h
Usage: radiff2 [-abcCdjrspOxuUvV] [-A[A]] [-g sym] [-t %] [file] [file]
-a [arch] specify architecture plugin to use (x86, arm, ..)
-A [-A] run aaa or aaaa after loading each binary (see -C)
-b [bits] specify register size for arch (16 (thumb), 32, 64, ..)
-c count of changes
-C graphdiff code (columns: off-A, match-ratio, off-B) (see -A)
-d use delta diffing
-D show disasm instead of hexpairs
-e [k=v] set eval config var value for all RCore instances
-g [sym|off1,off2] graph diff of given symbol, or between two offsets
-G [cmd] run an r2 command on every RCore instance created
-i diff imports of target files (see -u, -U and -z)
-j output in json format
-n print bare addresses only (diff.bare=1)
-O code diffing with opcode bytes only
-p use physical addressing (io.va=0)
-q quiet mode (disable colors, reduce output)
-r output in radare commands
-s compute text distance
-ss compute text distance (using levenstein algorithm)
-S [name] sort code diff (name, namelen, addr, size, type, dist) (only for -C or -g)
-t [0-100] set threshold for code diff (default is 70%)
-x show two column hexdump diffing
-u unified output (---+++)
-U unified output using system 'diff'
-v show version information
-V be verbose (current only for -s)
-z diff on extracted strings
radiff2 是一个基于偏移的比较工具。
重要参数:
-s
:计算文本距离并得到相似度。-AC
:这两个参数通常一起使用,从函数的角度进行比较。-g
:得到给定的符号或两个偏移的图像对比。- 如:
radiff2 -g main a.out b.out | xdot -
(需要安装xdot)
- 如:
-c
:计算不同点的数量。
rafind2
$ rafind2 -h
Usage: rafind2 [-mXnzZhv] [-a align] [-b sz] [-f/t from/to] [-[m|s|S|e] str] [-x hex] file ..
-a [align] only accept aligned hits
-b [size] set block size
-e [regex] search for regular expression string matches
-f [from] start searching from address 'from'
-h show this help
-m magic search, file-type carver
-M [str] set a binary mask to be applied on keywords
-n do not stop on read errors
-r print using radare commands
-s [str] search for a specific string (can be used multiple times)
-S [str] search for a specific wide string (can be used multiple times)
-t [to] stop search at address 'to'
-v print version and exit
-x [hex] search for hexpair string (909090) (can be used multiple times)
-X show hexdump of search results
-z search for zero-terminated strings
-Z show string found on each search hit
rafind2 用于在二进制文件中查找字符模式。
重要参数:
-s
:查找特定字符串。-e
:使用正则匹配。-z
:搜索以\0
结束的字符串。-x
:查找十六进制字符串。
ragg2
$ ragg2 -h
Usage: ragg2 [-FOLsrxhvz] [-a arch] [-b bits] [-k os] [-o file] [-I path]
[-i sc] [-e enc] [-B hex] [-c k=v] [-C file] [-p pad] [-q off]
[-q off] [-dDw off:hex] file|f.asm|-
-a [arch] select architecture (x86, mips, arm)
-b [bits] register size (32, 64, ..)
-B [hexpairs] append some hexpair bytes
-c [k=v] set configuration options
-C [file] append contents of file
-d [off:dword] patch dword (4 bytes) at given offset
-D [off:qword] patch qword (8 bytes) at given offset
-e [encoder] use specific encoder. see -L
-f [format] output format (raw, pe, elf, mach0)
-F output native format (osx=mach0, linux=elf, ..)
-h show this help
-i [shellcode] include shellcode plugin, uses options. see -L
-I [path] add include path
-k [os] operating system's kernel (linux,bsd,osx,w32)
-L list all plugins (shellcodes and encoders)
-n [dword] append 32bit number (4 bytes)
-N [dword] append 64bit number (8 bytes)
-o [file] output file
-O use default output file (filename without extension or a.out)
-p [padding] add padding after compilation (padding=n10s32)
ntas : begin nop, trap, 'a', sequence
NTAS : same as above, but at the end
-P [size] prepend debruijn pattern
-q [fragment] debruijn pattern offset
-r show raw bytes instead of hexpairs
-s show assembler
-v show version
-w [off:hex] patch hexpairs at given offset
-x execute
-z output in C string syntax
ragg2 可以将高级语言编写的简单程序编译成 x86、x86-64 或 ARM 的二进制文件。
重要参数:
-a
:设置体系结构。-b
:设置体系结构位数(32/64)。-P
:生成某种模式的字符串,常用于输入到某程序中并寻找溢出点。-r
:使用原始字符而不是十六进制对。- ragg2 -P 50 -r`
-i
:生成指定的 shellcode。查看-L
。ragg2 -a x86 -b 32 -i exec
-e
:使用指定的编码器。查看-L
。
rarun2
$ rarun2 -h
Usage: rarun2 -v|-t|script.rr2 [directive ..]
program=/bin/ls
arg1=/bin
# arg2=hello
# arg3="hello\nworld"
# arg4=:048490184058104849
# arg5=:!ragg2 -p n50 -d 10:0x8048123
# [email protected]
# arg7=@300@ABCD # 300 chars filled with ABCD pattern
# system=r2 -
# aslr=no
setenv=FOO=BAR
# unsetenv=FOO
# clearenv=true
# envfile=environ.txt
timeout=3
# timeoutsig=SIGTERM # or 15
# connect=localhost:8080
# listen=8080
# pty=false
# fork=true
# bits=32
# pid=0
# pidfile=/tmp/foo.pid
# #sleep=0
# #maxfd=0
# #execve=false
# #maxproc=0
# #maxstack=0
# #core=false
# #stdio=blah.txt
# #stderr=foo.txt
# stdout=foo.txt
# stdin=input.txt # or !program to redirect input to another program
# input=input.txt
# chdir=/
# chroot=/mnt/chroot
# libpath=$PWD:/tmp/lib
# r2preload=yes
# preload=/lib/libfoo.so
# setuid=2000
# seteuid=2000
# setgid=2001
# setegid=2001
# nice=5
rarun2 是一个可以使用不同环境、参数、标准输入、权限和文件描述符的启动器。
常用的参数设置:
program
arg1
,arg2
,...setenv
stdin
,stdout
例子:
rarun2 program=a.out arg1=$(ragg2 -P 300 -r)
rarun2 program=a.out stdin=$(python a.py)
rax2
$ rax2 -h
Usage: rax2 [options] [expr ...]
=[base] ; rax2 =10 0x46 -> output in base 10
int -> hex ; rax2 10
hex -> int ; rax2 0xa
-int -> hex ; rax2 -77
-hex -> int ; rax2 0xffffffb3
int -> bin ; rax2 b30
int -> ternary ; rax2 t42
bin -> int ; rax2 1010d
float -> hex ; rax2 3.33f
hex -> float ; rax2 Fx40551ed8
oct -> hex ; rax2 35o
hex -> oct ; rax2 Ox12 (O is a letter)
bin -> hex ; rax2 1100011b
hex -> bin ; rax2 Bx63
hex -> ternary ; rax2 Tx23
raw -> hex ; rax2 -S < /binfile
hex -> raw ; rax2 -s 414141
-b bin -> str ; rax2 -b 01000101 01110110
-B str -> bin ; rax2 -B hello
-d force integer ; rax2 -d 3 -> 3 instead of 0x3
-e swap endianness ; rax2 -e 0x33
-D base64 decode ;
-E base64 encode ;
-f floating point ; rax2 -f 6.3+2.1
-F stdin slurp C hex ; rax2 -F < shellcode.c
-h help ; rax2 -h
-k keep base ; rax2 -k 33+3 -> 36
-K randomart ; rax2 -K 0x34 1020304050
-n binary number ; rax2 -n 0x1234 # 34120000
-N binary number ; rax2 -N 0x1234 # \x34\x12\x00\x00
-r r2 style output ; rax2 -r 0x1234
-s hexstr -> raw ; rax2 -s 43 4a 50
-S raw -> hexstr ; rax2 -S < /bin/ls > ls.hex
-t tstamp -> str ; rax2 -t 1234567890
-x hash string ; rax2 -x linux osx
-u units ; rax2 -u 389289238 # 317.0M
-w signed word ; rax2 -w 16 0xffff
-v version ; rax2 -v
rax2 是一个格式转换工具,在二进制、八进制、十六进制数字和字符串之间进行转换。
重要参数:
-e
:交换字节顺序-s
:十六进制->字符-S
:字符->十六进制-D
,-E
:base64 解码和编码
交互式使用方法
当我们进入到 Radare2 的交互式界面后,就可以使用交互式命令进行操作。
输入 ?
可以获得帮助信息,由于命令太多,我们只会重点介绍一些常用命令:
[0x00000000]> ?
Usage: [.][times][cmd][~grep][@[@iter]addr!size][|>pipe] ; ...
Append '?' to any char command to get detailed help
Prefix with number to repeat command N times (f.ex: 3x)
|%var =valueAlias for 'env' command
| *[?] off[=[0x]value] Pointer read/write data/values (see ?v, wx, wv)
| (macro arg0 arg1) Manage scripting macros
| .[?] [-|(m)|f|!sh|cmd] Define macro or load r2, cparse or rlang file
| =[?] [cmd] Send/Listen for Remote Commands (rap://, http://, <fd>)
| /[?] Search for bytes, regexps, patterns, ..
| ![?] [cmd] Run given command as in system(3)
| #[?] !lang [..] Hashbang to run an rlang script
| a[?] Analysis commands
| b[?] Display or change the block size
| c[?] [arg] Compare block with given data
| C[?] Code metadata (comments, format, hints, ..)
| d[?] Debugger commands
| e[?] [a[=b]] List/get/set config evaluable vars
| f[?] [name][sz][at] Add flag at current address
| g[?] [arg] Generate shellcodes with r_egg
| i[?] [file] Get info about opened file from r_bin
| k[?] [sdb-query] Run sdb-query. see k? for help, 'k *', 'k **' ...
| L[?] [-] [plugin] list, unload load r2 plugins
| m[?] Mountpoints commands
| o[?] [file] ([offset]) Open file at optional address
| p[?] [len] Print current block with format and length
| P[?] Project management utilities
| q[?] [ret] Quit program with a return value
| r[?] [len] Resize file
| s[?] [addr] Seek to address (also for '0x', '0x1' == 's 0x1')
| S[?] Io section manipulation information
| t[?] Types, noreturn, signatures, C parser and more
| T[?] [-] [num|msg] Text log utility
| u[?] uname/undo seek/write
| V Enter visual mode (V! = panels, VV = fcngraph, VVV = callgraph)
| w[?] [str] Multiple write operations
| x[?] [len] Alias for 'px' (print hexadecimal)
| y[?] [len] [[[@]addr Yank/paste bytes from/to memory
| z[?] Zignatures management
| ?[??][expr] Help or evaluate math expression
| ?$? Show available '$' variables and aliases
| ?@? Misc help for '@' (seek), '~' (grep) (see ~??)
| ?:? List and manage core plugins
于是我们知道了 Radare2 交互命令的一般格式,如下所示:
[.][times][cmd][~grep][@[@iter]addr!size][|>pipe] ; ...
如果你对 *nix shell, sed, awk 等比较熟悉的话,也可以帮助你很快掌握 radare2 命令。
- 在任意字符命令后面加上
?
可以获得关于该命令更多的细节。如a?
、p?
、!?
、@?
。 - 当命令以数字开头时表示重复运行的次数。如
3x
。 !
单独使用可以显示命令使用历史记录。;
是命令分隔符,可以在一行上运行多个命令。如px 10; pd 20
。..
重复运行上一条命令,使用回车键也一样。/
用于在文件中进行搜索操作。- 以
!
开头可以运行 shell 命令。用法:!<cmd>
。!ls
|
是管道符。用法:<r2command> | <program|H|>
。pd | less
~
用于文本比配(grep)。用法:[command]~[modifier][word,word][endmodifier][[column]][:line]
。i~:0
显示i
输出的第一行pd~mov,eax
反汇编并匹配 mov 或 eax 所在行pi~mov&eax
匹配 mov 和 eax 都有的行i~0x400$
匹配以 0x400 结尾的行
???
可以获得以?
开头的命令的细节?
可以做各种进制和格式的快速转换。如? 1234
?p vaddr
获得虚拟地址 vaddr 的物理地址?P paddr
获得物理地址 paddr 的虚拟地址?v
以十六进制的形式显示某数学表达式的结果。如?v eip-0x804800
。?l str
获得 str 的长度,结果被临时保存,使用?v
可输出结果。
@@
foreach 迭代器,在列出的偏移处重复执行命令。wx ff @@ 10 20 30
在偏移 10、20、30 处写入 ffp8 4 @@ fcn.*
打印处每个函数的头 4 个字节
?$?
可以显示表达式所使用变量的帮助信息。用法:?v [$.]
。$$
是当前所处的虚拟地址$?
是最后一个运算的值$s
文件大小$b
块大小$l
操作码长度$j
跳转地址。当$$
处是一个类似jmp
的指令时,$j
中保存着将要跳转到的地址$f
跳转失败地址。即当前跳转没有生效,$f
中保存下一条指令的地址$m
操作码内存引用。如:mov eax,[0x10] => 0x10
e
用于进行配置信息的修改e asm.bytes=false
关闭指令 raw bytes 的显示
默认情况下,执行的每条命令都有一个参考点,通常是内存中的当前位置,由命令前的十六进制数字指示。任何的打印、写入或分析命令都在当前位置执行。例如反汇编当前位置的一条指令:
[0x00005060]> pd 1
;-- entry0:
;-- rip:
0x00005060 31ed xor ebp, ebp
block size 是在我们没有指定行数的时候使用的默认值,输入 b
即可看到,使用 b [num]
修改字节数,这时使用打印命令如 pd
时,将反汇编相应字节的指令。
[0x00005060]> b
0x100
[0x00005060]> b 10
[0x00005060]> b
0xa
[0x00005060]> pd
;-- entry0:
;-- rip:
0x00005060 31ed xor ebp, ebp
0x00005062 4989d1 mov r9, rdx
分析(analyze)
所有与分析有关的命令都以 a
开头:
[0x00000000]> a?
|Usage: a[abdefFghoprxstc] [...]
| ab [hexpairs] analyze bytes
| abb [len] analyze N basic blocks in [len] (section.size by default)
| aa[?] analyze all (fcns + bbs) (aa0 to avoid sub renaming)
| ac [cycles] analyze which op could be executed in [cycles]
| ad[?] analyze data trampoline (wip)
| ad [from] [to] analyze data pointers to (from-to)
| ae[?] [expr] analyze opcode eval expression (see ao)
| af[?] analyze Functions
| aF same as above, but using anal.depth=1
| ag[?] [options] output Graphviz code
| ah[?] analysis hints (force opcode size, ...)
| ai [addr] address information (show perms, stack, heap, ...)
| ao[?] [len] analyze Opcodes (or emulate it)
| aO Analyze N instructions in M bytes
| ar[?] like 'dr' but for the esil vm. (registers)
| ap find prelude for current offset
| ax[?] manage refs/xrefs (see also afx?)
| as[?] [num] analyze syscall using dbg.reg
| at[?] [.] analyze execution traces
| av[?] [.] show vtables
[0x00000000]> aa?
|Usage: aa[0*?] # see also 'af' and 'afna'
| aa alias for 'af@@ sym.*;af@entry0;afva'
| aa* analyze all flags starting with sym. (af @@ sym.*)
| aaa[?] autoname functions after aa (see afna)
| aab aab across io.sections.text
| aac [len] analyze function calls (af @@ `pi len~call[1]`)
| aad [len] analyze data references to code
| aae [len] ([addr]) analyze references with ESIL (optionally to address)
| aai[j] show info of all analysis parameters
| aar[?] [len] analyze len bytes of instructions for references
| aan autoname functions that either start with fcn.* or sym.func.*
| aas [len] analyze symbols (af @@= `isq~[0]`)
| aat [len] analyze all consecutive functions in section
| aaT [len] analyze code after trap-sleds
| aap find and analyze function preludes
| aav [sat] find values referencing a specific section or map
| aau [len] list mem areas (larger than len bytes) not covered by functions
afl
:列出所有函数。axt [addr]
:找到对给定地址的交叉引用。af [addr]
:当你发现某个地址处有一个函数,但是没有被分析出来的时候,可以使用该命令重新分析。
Flags
flag 用于将给定的偏移与名称相关联,flag 被分为几个 flag spaces,用于存放不同的 flag。
[0x00000000]> f?
|Usage: f [?] [flagname] # Manage offset-name flags
| f list flags (will only list flags from selected flagspaces)
| f?flagname check if flag exists or not, See ?? and ?!
| f. [*[*]] list local per-function flags (*) as r2 commands
| f.blah=$$+12 set local function label named 'blah'
| f* list flags in r commands
| f name 12 @ 33 set flag 'name' with length 12 at offset 33
| f name = 33 alias for 'f name @ 33' or 'f name 1 33'
| f name 12 33 [cmt] same as above + optional comment
| [email protected] delete local label from function at current seek (also f.-)
| f-- delete all flags and flagspaces (deinit)
| f+name 12 @ 33 like above but creates new one if doesnt exist
| f-name remove flag 'name'
| f-@addr remove flag at address expression
| f. fname list all local labels for the given function
| f= [glob] list range bars graphics with flag offsets and sizes
| fa [name] [alias] alias a flag to evaluate an expression
| fb [addr] set base address for new flags
| fb [addr] [flag*] move flags matching 'flag' to relative addr
| fc[?][name] [color] set color for given flag
| fC [name] [cmt] set comment for given flag
| fd addr return flag+delta
| fe- resets the enumerator counter
| fe [name] create flag name.#num# enumerated flag. See fe?
| fi [size] | [from] [to] show flags in current block or range
| fg bring visual mode to foreground
| fj list flags in JSON format
| fl (@[flag]) [size] show or set flag length (size)
| fla [glob] automatically compute the size of all flags matching glob
| fm addr move flag at current offset to new address
| fn list flags displaying the real name (demangled)
| fo show fortunes
| fr [old] [[new]] rename flag (if no new flag current seek one is used)
| fR[?] [f] [t] [m] relocate all flags matching f&~m 'f'rom, 't'o, 'm'ask
| fs[?]+-* manage flagspaces
| fS[on] sort flags by offset or name
| fV[*-] [nkey] [offset] dump/restore visual marks (mK/'K)
| fx[d] show hexdump (or disasm) of flag:flagsize
| fz[?][name] add named flag zone -name to delete. see fz?[name]
常见用法:
f flag_name @ addr
:给地址 addr 创建一个 flag,当不指定地址时则默认指定当前地址。f-flag_name
:删除flag。fs
:管理命名空间。[0x00005060]> fs? |Usage: fs [*] [+-][flagspace|addr] # Manage flagspaces | fs display flagspaces | fs* display flagspaces as r2 commands | fsj display flagspaces in JSON | fs * select all flagspaces | fs flagspace select flagspace or create if it doesn't exist | fs-flagspace remove flagspace | fs-* remove all flagspaces | fs+foo push previous flagspace and set | fs- pop to the previous flagspace | fs-. remove the current flagspace | fsm [addr] move flags at given address to the current flagspace | fss display flagspaces stack | fss* display flagspaces stack in r2 commands | fssj display flagspaces stack in JSON | fsr newname rename selected flagspace
定位(seeking)
使用 s
命令可以改变当前位置:
[0x00000000]> s?
|Usage: s # Seek commands
| s Print current address
| s:pad Print current address with N padded zeros (defaults to 8)
| s addr Seek to address
| s- Undo seek
| s- n Seek n bytes backward
| s-- Seek blocksize bytes backward
| s+ Redo seek
| s+ n Seek n bytes forward
| s++ Seek blocksize bytes forward
| s[j*=!] List undo seek history (JSON, =list, *r2, !=names, s==)
| s/ DATA Search for next occurrence of 'DATA'
| s/x 9091 Search for next occurrence of \x90\x91
| s.hexoff Seek honoring a base from core->offset
| sa [[+-]a] [asz] Seek asz (or bsize) aligned to addr
| sb Seek aligned to bb start
| sC[?] string Seek to comment matching given string
| sf Seek to next function (f->addr+f->size)
| sf function Seek to address of specified function
| sg/sG Seek begin (sg) or end (sG) of section or file
| sl[?] [+-]line Seek to line
| sn/sp Seek to next/prev location, as specified by scr.nkey
| so [N] Seek to N next opcode(s)
| sr pc Seek to register
| ss Seek silently (without adding an entry to the seek history)
s+
,s-
:重复或撤销。s+ n
,s- n
:定位到当前位置向前或向后 n 字节的位置。s/ DATA
:定位到下一个出现 DATA 的位置。
信息(information)
[0x00000000]> i?
|Usage: i Get info from opened file (see rabin2's manpage)
| Output mode:
| '*' Output in radare commands
| 'j' Output in json
| 'q' Simple quiet output
| Actions:
| i|ij Show info of current file (in JSON)
| iA List archs
| ia Show all info (imports, exports, sections..)
| ib Reload the current buffer for setting of the bin (use once only)
| ic List classes, methods and fields
| iC Show signature info (entitlements, ...)
| id[?] Debug information (source lines)
| iD lang sym demangle symbolname for given language
| ie Entrypoint
| iE Exports (global symbols)
| ih Headers (alias for iH)
| iHH Verbose Headers in raw text
| ii Imports
| iI Binary info
| ik [query] Key-value database from RBinObject
| il Libraries
| iL [plugin] List all RBin plugins loaded or plugin details
| im Show info about predefined memory allocation
| iM Show main address
| io [file] Load info from file (or last opened) use bin.baddr
| ir Relocs
| iR Resources
| is Symbols
| iS [entropy,sha1] Sections (choose which hash algorithm to use)
| iV Display file version info
| iz|izj Strings in data sections (in JSON/Base64)
| izz Search for Strings in the whole binary
| iZ Guess size of binary program
i
系列命令用于获取文件的各种信息,这时配合上 ~
命令来获得精确的输出,下面是一个类似 checksec 的输出:
[0x00005060]> iI ~relro,canary,nx,pic,rpath
canary true
nx true
pic true
relro full
rpath NONE
~
命令还有一些其他的用法,如获取某一行某一列等,另外使用 ~{}
可以使 json 的输出更好看:
[0x00005060]> ~?
|Usage: [command]~[modifier][word,word][endmodifier][[column]][:line]
modifier:
| & all words must match to grep the line
| $[n] sort numerically / alphabetically the Nth column
| + case insensitive grep (grep -i)
| ^ words must be placed at the beginning of line
| ! negate grep
| ? count number of matching lines
| ?. count number chars
| ?? show this help message
| :[s]-[e] show lines s-e
| .. internal 'less'
| ... internal 'hud' (like V_)
| {} json indentation
| {path} json grep
| {}.. less json indentation
| endmodifier:
| $ words must be placed at the end of line
| column:
| [n] show only column n
| [n-m] show column n to m
| [n-] show all columns starting from column n
| [i,j,k] show the columns i, j and k
| Examples:
| i~:0 show first line of 'i' output
| i~:-2 show first three lines of 'i' output
| pd~mov disasm and grep for mov
| pi~[0] show only opcode
| i~0x400$ show lines ending with 0x400
打印(print) & 反汇编(disassembling)
[0x00000000]> p?
|Usage: p[=68abcdDfiImrstuxz] [arg|len] [@addr]
| p=[?][bep] [blks] [len] [blk] show entropy/printable chars/chars bars
| p2 [len] 8x8 2bpp-tiles
| p3 [file] print stereogram (3D)
| p6[de] [len] base64 decode/encode
| p8[?][j] [len] 8bit hexpair list of bytes
| pa[edD] [arg] pa:assemble pa[dD]:disasm or pae: esil from hexpairs
| pA[n_ops] show n_ops address and type
| p[b|B|xb] [len] ([skip]) bindump N bits skipping M
| pb[?] [n] bitstream of N bits
| pB[?] [n] bitstream of N bytes
| pc[?][p] [len] output C (or python) format
| pC[d] [rows] print disassembly in columns (see hex.cols and pdi)
| pd[?] [sz] [a] [b] disassemble N opcodes (pd) or N bytes (pD)
| pf[?][.nam] [fmt] print formatted data (pf.name, pf.name $<expr>)
| ph[?][=|hash] ([len]) calculate hash for a block
| p[iI][df] [len] print N ops/bytes (f=func) (see pi? and pdi)
| pm[?] [magic] print libmagic data (see pm? and /m?)
| pr[?][glx] [len] print N raw bytes (in lines or hexblocks, 'g'unzip)
| p[kK] [len] print key in randomart (K is for mosaic)
| ps[?][pwz] [len] print pascal/wide/zero-terminated strings
| pt[?][dn] [len] print different timestamps
| pu[?][w] [len] print N url encoded bytes (w=wide)
| pv[?][jh] [mode] show variable/pointer/value in memory
| p-[?][jh] [mode] bar|json|histogram blocks (mode: e?search.in)
| px[?][owq] [len] hexdump of N bytes (o=octal, w=32bit, q=64bit)
| pz[?] [len] print zoom view (see pz? for help)
| pwd display current working directory
常用参数如下:
px
:输出十六进制数、偏移和原始数据。后跟o
,w
,q
时分别表示8位、32位和64位。p8
:输出8位的字节流。ps
:输出字符串。
radare2 中反汇编操作是隐藏在打印操作中的,即使用 pd
:
[0x00000000]> pd?
|Usage: p[dD][ajbrfils] [sz] [arch] [bits] # Print Disassembly
| NOTE: len parameter can be negative
| NOTE: Pressing ENTER on empty command will repeat last pd command and also seek to end of disassembled range.
| pd N disassemble N instructions
| pd -N disassemble N instructions backward
| pD N disassemble N bytes
| pda disassemble all possible opcodes (byte per byte)
| pdb disassemble basic block
| pdc pseudo disassembler output in C-like syntax
| pdC show comments found in N instructions
| pdk disassemble all methods of a class
| pdj disassemble to json
| pdr recursive disassemble across the function graph
| pdf disassemble function
| pdi like 'pi', with offset and bytes
| pdl show instruction sizes
| pds[?] disassemble summary (strings, calls, jumps, refs) (see pdsf and pdfs)
| pdt disassemble the debugger traces (see atd)
@addr
表示一个相对寻址,这里的 addr 可以是地址、符号名等,这个操作和 s
命令不同,它不会改变当前位置,当然即使使用类似 s @addr
的命令也不会改变当前位置。
[0x00005060]> pd 5 @ main
;-- main:
;-- section..text:
0x00003620 4157 push r15 ; section 13 va=0x00003620 pa=0x00003620 sz=75529 vsz=75529 rwx=--r-x .text
0x00003622 4156 push r14
0x00003624 4155 push r13
0x00003626 4154 push r12
0x00003628 55 push rbp
[0x00005060]> s @ main
0x3620
[0x00005060]> s 0x3620
[0x00003620]>
写入(write)
当你在打开 r2 时使用了参数 -w
时,才可以使用该命令,w
命令用于写入字节,它允许多种输入格式:
[0x00000000]> w?
|Usage: w[x] [str] [<file] [<<EOF] [@addr]
| w[1248][+-][n] increment/decrement byte,word..
| w foobar write string 'foobar'
| w0 [len] write 'len' bytes with value 0x00
| w6[de] base64/hex write base64 [d]ecoded or [e]ncoded string
| wa[?] push ebp write opcode, separated by ';' (use '"' around the command)
| waf file assemble file and write bytes
| wao[?] op modify opcode (change conditional of jump. nop, etc)
| wA[?] r 0 alter/modify opcode at current seek (see wA?)
| wb 010203 fill current block with cyclic hexpairs
| wB[-]0xVALUE set or unset bits with given value
| wc list all write changes
| wc[?][ir*?] write cache undo/commit/reset/list (io.cache)
| wd [off] [n] duplicate N bytes from offset at current seek (memcpy) (see y?)
| we[?] [nNsxX] [arg] extend write operations (insert instead of replace)
| wf -|file write contents of file at current offset
| wh r2 whereis/which shell command
| wm f0ff set binary mask hexpair to be used as cyclic write mask
| wo[?] hex write in block with operation. 'wo?' fmi
| wp[?] -|file apply radare patch file. See wp? fmi
| wr 10 write 10 random bytes
| ws pstring write 1 byte for length and then the string
| wt[f][?] file [sz] write to file (from current seek, blocksize or sz bytes)
| wts host:port [sz] send data to remote host:port via tcp://
| ww foobar write wide string 'f\x00o\x00o\x00b\x00a\x00r\x00'
| wx[?][fs] 9090 write two intel nops (from wxfile or wxseek)
| wv[?] eip+34 write 32-64 bit value
| wz string write zero terminated string (like w + \x00)
常见用法:
wa
:写入操作码,如wa jmp 0x8048320
wx
:写入十六进制数。wv
:写入32或64位的值。wo
:有很多子命令,用于将当前位置的值做运算后覆盖原值。[0x00005060]> wo? |Usage: wo[asmdxoArl24] [hexpairs] @ addr[!bsize] | wo[24aAdlmorwx] without hexpair values, clipboard is used | wo2 [val] 2= 2 byte endian swap | wo4 [val] 4= 4 byte endian swap | woa [val] += addition (f.ex: woa 0102) | woA [val] &= and | wod [val] /= divide | woD[algo] [key] [IV] decrypt current block with given algo and key | woe [from to] [step] [wsz=1] .. create sequence | woE [algo] [key] [IV] encrypt current block with given algo and key | wol [val] <<= shift left | wom [val] *= multiply | woo [val] |= or | wop[DO] [arg] De Bruijn Patterns | wor [val] >>= shift right | woR random bytes (alias for 'wr $b') | wos [val] -= substraction | wow [val] == write looped value (alias for 'wb') | wox [val] ^= xor (f.ex: wox 0x90)
调试(debugging)
在开启 r2 时使用参数 -d
即可开启调试模式,当然如果你已经加载了程序,可以使用命令 ood
重新开启调试。
[0x7f8363c75f30]> d?
|Usage: d # Debug commands
| db[?] Breakpoints commands
| dbt[?] Display backtrace based on dbg.btdepth and dbg.btalgo
| dc[?] Continue execution
| dd[?] File descriptors (!fd in r1)
| de[-sc] [rwx] [rm] [e] Debug with ESIL (see de?)
| dg <file> Generate a core-file (WIP)
| dH [handler] Transplant process to a new handler
| di[?] Show debugger backend information (See dh)
| dk[?] List, send, get, set, signal handlers of child
| dL [handler] List or set debugger handler
| dm[?] Show memory maps
| do[?] Open process (reload, alias for 'oo')
| doo[args] Reopen in debugger mode with args (alias for 'ood')
| dp[?] List, attach to process or thread id
| dr[?] Cpu registers
| ds[?] Step, over, source line
| dt[?] Display instruction traces (dtr=reset)
| dw <pid> Block prompt until pid dies
| dx[?] Inject and run code on target process (See gs)
视图模式
在调试时使用视图模式是十分有用的,因为你既可以查看程序当前的位置,也可以查看任何你想看的位置。输入 V
即可进入视图模式,按下 p/P
可在不同模式之间进行切换,按下 ?
即可查看帮助,想退出时按下 q
。
Visual mode help:
? show this help
?? show the user-friendly hud
$ toggle asm.pseudo
% in cursor mode finds matching pair, otherwise toggle autoblocksz
@ redraw screen every 1s (multi-user view), in cursor set position
! enter into the visual panels mode
_ enter the flag/comment/functions/.. hud (same as VF_)
= set cmd.vprompt (top row)
| set cmd.cprompt (right column)
. seek to program counter
" toggle the column mode (uses pC..)
/ in cursor mode search in current block
:cmd run radare command
;[-]cmt add/remove comment
0 seek to beginning of current function
[1-9] follow jmp/call identified by shortcut (like ;[1])
,file add a link to the text file
/*+-[] change block size, [] = resize hex.cols
</> seek aligned to block size (seek cursor in cursor mode)
a/A (a)ssemble code, visual (A)ssembler
b toggle breakpoint
B enumerate and inspect classes
c/C toggle (c)ursor and (C)olors
d[f?] define function, data, code, ..
D enter visual diff mode (set diff.from/to)
e edit eval configuration variables
f/F set/unset or browse flags. f- to unset, F to browse, ..
gG go seek to begin and end of file (0-$s)
hjkl move around (or HJKL) (left-down-up-right)
i insert hex or string (in hexdump) use tab to toggle
mK/'K mark/go to Key (any key)
M walk the mounted filesystems
n/N seek next/prev function/flag/hit (scr.nkey)
o go/seek to given offset
O toggle asm.esil
p/P rotate print modes (hex, disasm, debug, words, buf)
q back to radare shell
r refresh screen / in cursor mode browse comments
R randomize color palette (ecr)
sS step / step over
t browse types
T enter textlog chat console (TT)
uU undo/redo seek
v visual function/vars code analysis menu
V (V)iew graph using cmd.graph (agv?)
wW seek cursor to next/prev word
xX show xrefs/refs of current function from/to data/code
yY copy and paste selection
z fold/unfold comments in disassembly
Z toggle zoom mode
Enter follow address of jump/call
Function Keys: (See 'e key.'), defaults to:
F2 toggle breakpoint
F4 run to cursor
F7 single step
F8 step over
F9 continue
视图模式下的命令和命令行模式下的命令有很大不同,下面列出几个,更多的命令请查看帮助:
o
:定位到给定的偏移。;
:添加注释。V
:查看图形。:
:运行 radare2 命令
Web 界面使用
Radare2 的 GUI 尚在开发中,但有一个 Web 界面可以使用,如果刚开始你不习惯命令行操作,可以输入下面的命令:
$ r2 -c=H [filename]
默认地址为 http://localhost:9090/
,这样你就可以在 Web 中进行操作了,但是我强烈建议你强迫自己使用命令行的操作方式。
cutter GUI
cutter 是 r2 官方的 GUI,已经在快速开发中,基本功能已经有了,喜欢界面操作的读者可以试一下(请确保 r2 已经正确安装):
$ yaourt -S qt
$ git clone https://github.com/radareorg/cutter
$ cd cutter
$ mkdir build
$ cd build
$ qmake ../src
$ make
然后就可以运行了:
$ ./cutter