Radare2 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@ [funcname](Tab) | Disassemble function (main, fcn, etc.) |
| f fcn(Tab) | List functions |
| f str(Tab) | List strings |
| fr [flagname] [newname] | Rename flag |
| psz [offset]~grep | Print strings and grep for one |
| axF [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 [flagname] | 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 [space] | 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 | Toggle asm.pseudo and asm.esil |
| . | Seek to program counter |
| / | In cursor mode, search in current block |
| :cmd | Run radare command |
| ;[-]cmt | Add/remove comment |
| /*+-[] | Change block size, [] = resize hex.cols |
| <,> | Seek aligned to block size |
| i/a/A | (i)nsert hex, (a)ssemble code, visual (A)ssembler |
| b | Toggle breakpoint |
| B | Browse evals, symbols, flags, classes, ... |
| 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) |
| C | Toggle (C)olors |
| R | Randomize color palette (ecr) |
| tT | Tab related. see also tab |
| v | Visual code analysis menu |
| V | (V)iew graph (agv?) |
| wW | Seek cursor to next/prev word |
| uU | Undo/redo seek |
| x | Show xrefs of current func from/to data/code |
| yY | Copy and paste selection |
| z | fold/unfold comments in diassembly |
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 (Broken)
This feature has broken and not been resolved at the time of writing these words (Nov.16th 2020). check #Issue 6945: META - Project files and #Issue 17034 for more details.
To save your analysis for now, write your own script which records the function name, variable name, etc. for example:
vim sample_A.r2
e scr.utf8 = false
s 0x000403ce0
aaa
s fcn.00403130
afn return_delta_to_heapaddr
afvn iter var_04h
...
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 |