Reference Card

This chapter is based on the Radare 2 reference card by Thanat0s, which is under the GNU GPL. Original license is as follows:

This card may be freely distributed under the terms of the GNU
general public licence — Copyright by Thanat0s - v0.1 -

Survival Guide

Those are the basic commands you will want to know and use for moving around a binary and getting information about it.

Command	Description
s (tab)	Seek to a different place
x [nbytes]	Hexdump of nbytes, $b by default
aa	Auto analyze
pdf@fcn(Tab)	Disassemble function
f fcn(Tab)	List functions
f str(Tab)	List strings
fr [flagname] [newname]	Rename flag
psz [offset]~grep	Print strings and grep for one
arf [flag]	Find cross reference for a flag

Flags

Flags are like bookmarks, but they carry some extra information like size, tags or associated flagspace. Use the f command to list, set, get them.

Command	Description
f	List flags
fd $$	Describe an offset
fj	Display flags in JSON
fl	Show flag length
fx	Show hexdump of flag
fC [name] [comment]	Set flag comment

Flagspaces

Flags are created into a flagspace, by default none is selected, and listing flags will list them all. To display a subset of flags you can use the fs command to restrict it.

Command	Description
fs	Display flagspaces
fs *	Select all flagspaces
fs [sections]	Select one flagspace

Information

Binary files have information stored inside the headers. The i command uses the RBin api and allows us to the same things rabin2 do. Those are the most common ones.

Command	Description
ii	Information on imports
iI	Info on binary
ie	Display entrypoint
iS	Display sections
ir	Display relocations
iz	List strings (izz, izzz)

Print string

There are different ways to represent a string in memory. The ps command allows us to print it in utf-16, pascal, zero terminated, .. formats.

Command	Description
psz [offset]	Print zero terminated string
psb [offset]	Print strings in current block
psx [offset]	Show string with scaped chars
psp [offset]	Print pascal string
psw [offset]	Print wide string

Visual mode

The visual mode is the standard interactive interface of radare2.

To enter in visual mode use the v or V command, and then you'll only have to press keys to get the actions happen instead of commands.

Command	Description
V	Enter visual mode
p/P	Rotate modes (hex, disasm, debug, words, buf)
c	Toggle (c)ursor
q	Back to Radare shell
hjkl	Move around (or HJKL) (left-down-up-right)
Enter	Follow address of jump/call
sS	Step/step over
o	Go/seek to given offset
.	Seek to program counter
/	In cursor mode, search in current block
:cmd	Run radare command
;[-]cmt	Add/remove comment
x+-/[]	Change block size, [] = resize hex.cols
>||<	Seek aligned to block size
i/a/A	(i)nsert hex, (a)ssemble code, visual (A)ssembler
b/B	Toggle breakpoint / automatic block size
d[f?]	Define function, data, code, ..
D	Enter visual diff mode (set diff.from/to)
e	Edit eval configuration variables
f/F	Set/unset flag
gG	Go seek to begin and end of file (0-$s)
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
C	Toggle (C)olors
R	Randomize color palette (ecr)
t	Track flags (browse symbols, functions..)
T	Browse anal info and comments
v	Visual code analysis menu
V/W	(V)iew graph (agv?), open (W)ebUI
uU	Undo/redo seek
x	Show xrefs to seek between them
yY	Copy and paste selection
z	Toggle zoom mode

Searching

There are many situations where we need to find a value inside a binary or in some specific regions. Use the e search.in=? command to choose where the / command may search for the given value.

Command	Description
/ foo\00	Search for string ’foo\0’
/b	Search backwards
//	Repeat last search
/w foo	Search for wide string ’f\0o\0o\0’
/wi foo	Search for wide string ignoring case
/! ff	Search for first occurrence not matching
/i foo	Search for string ’foo’ ignoring case
/e /E.F/i	Match regular expression
/x a1b2c3	Search for bytes; spaces and uppercase nibbles are allowed, same as /x A1 B2 C3
/x a1..c3	Search for bytes ignoring some nibbles (auto-generates mask, in this example: ff00ff)
/x a1b2:fff3	Search for bytes with mask (specify individual bits)
/d 101112	Search for a deltified sequence of bytes
/!x 00	Inverse hexa search (find first byte != 0x00)
/c jmp [esp]	Search for asm code (see search.asmstr)
/a jmp eax	Assemble opcode and search its bytes
/A	Search for AES expanded keys
/r sym.printf	Analyze opcode reference an offset
/R	Search for ROP gadgets
/P	Show offset of previous instruction
/m magicfile	Search for matching magic file
/p patternsize	Search for pattern of given size
/z min max	Search for strings of given size
/v[?248] num	Look for a asm.bigendian 32bit value

Saving

By default, when you open a file in write mode (r2 -w) all changes will be written directly into the file. No undo history is saved by default.

Use e io.cache.write=true and the wc command to manage the write cache history changes. To undo, redo, commit them to write the changes on the file..

If, instead, we want to save the analysis information, comments, flags and other user-created metadata, we may want to use projects with r2 -p and the P command.

Command	Description
Po [file]	Open project
Ps [file]	Save project
Pi [file]	Show project information

Usable variables in expression

The ?$? command will display the variables that can be used in any math operation inside the r2 shell. For example, using the ? $$ command to evaluate a number or ?v to just the value in one format.

All commands in r2 that accept a number supports the use of those variables.

Command	Description
$$	here (current virtual seek)
$$$	current non-temporary virtual seek
$?	last comparison value
$alias=value	alias commands (simple macros)
$b	block size
$B	base address (aligned lowest map address)
$f	jump fail address (e.g. jz 0x10 => next instruction)
$fl	flag length (size) at current address (fla; pD $l @ entry0)
$F	current function size
$FB	begin of function
$Fb	address of the current basic block
$Fs	size of the current basic block
$FE	end of function
$FS	function size
$Fj	function jump destination
$Ff	function false destination
$FI	function instructions
$c,$r	get width and height of terminal
$Cn	get nth call of function
$Dn	get nth data reference in function
$D	current debug map base address ?v $D @ rsp
$DD	current debug map size
$e	1 if end of block, else 0
$j	jump address (e.g. jmp 0x10, jz 0x10 => 0x10)
$Ja	get nth jump of function
$Xn	get nth xref of function
$l	opcode length
$m	opcode memory reference (e.g. mov eax,[0x10] => 0x10)
$M	map address (lowest map address)
$o	here (current disk io offset)
$p	getpid()
$P	pid of children (only in debug)
$s	file size
$S	section offset
$SS	section size
$v	opcode immediate value (e.g. lui a0,0x8010 => 0x8010)
$w	get word size, 4 if asm.bits=32, 8 if 64, ...
${ev}	get value of eval config variable
$r{reg}	get value of named register
$k{kv}	get value of an sdb query value
$s{flag}	get size of flag
RNum	$variables usable in math expressions