The `rax2` utility comes with the radare framework and aims to be a minimalistic expression evaluator for the shell. It is useful for making base conversions between floating point values, hexadecimal representations, hexpair strings to ascii, octal to integer. It supports endianness conversion.
This is the help message of rax2, this tool can be used in the command-line or interactively (reading the values from stdin), so it can be used as a multi-base calculator.
Inside r2, the functionality of rax2 is available under the ? command. For example:
[0x00000000]> ? 3+4
As you can see, the numeric expressions can contain mathematical expressions like addition, substraction, .. as well as group operations with parenthesis.
The syntax in which the numbers are represented define the base, for example:
- 3 : decimal, base 10
- 0xface : hexadecimal, base 16
- 0472 : octal, base 8
- 2M : units, 2 megabytes
- ...
This is the help message of rax2 -h, which will show you a bunch more syntaxes
$ 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 ternary -> int ; rax2 1010dt 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 ternary -> hex ; rax2 212t hex -> ternary ; rax2 Tx23 raw -> hex ; rax2 -S < /binfile hex -> raw ; rax2 -s 414141 -l ; append newline to output (for -E/-D/-r/.. -a show ascii table ; rax2 -a -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 code hex ; rax2 -F < shellcode.[c/py/js] -h help ; rax2 -h -i dump as C byte array ; rax2 -i < bytes -k keep base ; rax2 -k 33+3 -> 36 -K randomart ; rax2 -K 0x34 1020304050 -L bin -> hex(bignum) ; rax2 -L 111111111 # 0x1ff -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
Some examples:
Calculator: ```sh $ rax2 3+0x80 0x83 $ rax2 -d "1<<8" 256 ```
Base conversion: ```sh $ rax2 '=2' 73303325 100010111101000010100011101b ``` The single quote for `'=2'` is not mandatory for bash but is necessary for some shell like zsh.
Conversion in hex string ```sh $ rax2 -s 4142 AB $ rax2 -S AB 4142 $ rax2 -S < bin.foo ...
Endianess conversion:
$ rax2 -e 33 0x21000000 $ rax2 -e 0x21000000 33 ```
Base64 deconding ```sh $ rax2 -D ZQBlAA== | rax2 -S 65006500 ```
Randomart: ```sh $ rax2 -K 90203010 +--[0x10302090]+ ```